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  • 1970-1974  (6,335)
  • 1965-1969  (5,803)
  • Inorganic Chemistry  (8,062)
  • Industrial Chemistry  (3,384)
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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Anatomy and embryology 143 (1974), S. 115-126 
    ISSN: 1432-0568
    Keywords: Cerebral cortex ; Apical dendrites ; Dendritic bundles ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In frontal, horizontal and sagittal paraffin sections through the cat's brain regional differences in the pattern of dendritic bundling have been investigated. It is shown that in the gyrus splenialis and suprasplenialis 2–5 apical dendrites of layer IV pyramids approach each other to form vertical bundles which run straight through layer IV. In the posterior sigmoid gyrus, on the other hand, most apical dendrites arising from the pyramidal cells bifurcate immediately above layer V and give rise to obliquely running branches which cross each other before turning upwards and joining other dendrites to take part in the formation of bundles. In this region the dendritic tree of the pyramidal cells seems to be characterized by an unexpectedly high degree of directional specialization.—In functional terms the findings can be summarized by stating that in the visual and sensorimotor regions of the cat's cerebral cortex basic differences exist in the relation between the apical dendrites of layer V pyramids.
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Anatomy and embryology 146 (1974), S. 141-156 
    ISSN: 1432-0568
    Keywords: Tapetum lucidum cellulosum ; Cat ; Development ; Light and electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die postnatale Entwicklung des Tapetum lucidum cellulosum der Katze wird mit licht- und elektronenmikroskopischen Methoden untersucht. Bereits am ersten postnatalen Tag sind im Bereich des prospektiven Tapetum zwei Zellarten voneinander zu unterscheiden: 1. mesenchymale Bindegewebszellen und 2. prospektive Tapetumzellen, die durch elektronendichte Tapetumstäbchen gekennzeichnet sind. Die Mesenchymzellen unterteilen als parallel zur Retinaoberfläche ausgebreitete Zellplatten in der Choriodea am hinteren Augenpol den weiten extracellulären Raum in 20–25 etwa 5 μm hohe Schichten. Die Tapetumzellen liegen zwischen den Mesenchymzellplatten und wachsen im Verlaufe der ersten vier postnatalen Wochen innerhalb der Schichten in die Breite, bis sie den extracellulären Raum vollständig ausfüllen und als polygonale Zellen direkt aneinander grenzen. Im weiteren Verlauf der Entwicklung werden die Mesenchymzellplatten rückgebildet, so daß bei der adulten Katze die Tapetumzellschichten direkt übereinander liegen und nur von Netzen elastischer und kollagener Fasern getrennt sind. Die von einer Elementarmembran umgebenen Tapetumstäbchen enthalten einen elektronendichten, in den ersten postnatalen Wochen mit einer Periode von 100 Å quergestreiften Kern. Zunächst nehmen sie an Zahl und Länge zu und füllen am Ende der vierten postnatalen Woche, zu Bündeln von parallel verlaufenden Stäbchen geordnet, das Cytoplasma der Tapetumzellen. Dann nehmen die Tapetumstäbchen an Dicke zu, und ihre Querstreifung wird von einem elektronendichten Material überlagert. Die Entwicklung der Tapetumstäbchen hat eine starke Ähnlichkeit mit der in der Literatur beschriebenen Entwicklung von Melanosomen in Melanocyten. Das Tapetum lucidum cellulosum wird als ein dichter Verband hochdifferenzierter extrakutaner Melanocyten angesehen.
    Notes: Summary The postnatal development of the tapetum lucidum cellulosum of the cat was studied by light and electron microscopy. Already by the first postnatal day two cell types can be distinguished in the prospective tapeta area: 1. mesenchymal cells and 2. prospective tapetal cells, characterized by electron dense, membrane bound, rod-like inclusions. The flattened mesenchymal elements form 20–25 separate layers of cells, which are arranged parallel to the surface of the retina, subdividing the extracellular space of the chorioidea at the posterior pole of the eye into 5 μm high compartments. These compartments contain the tapetal cells which enlarge (in their longitudinal axis) during the first four weeks post partum until they occupy the extracellular space almost completely. At this stage, the tapetal cells are polygonal in shape and closely attached to each other. During the subsequent period of development there is a gradual involution of the mesenchymal cell plates. Thus, in adult cats the individual layers of tapetal cells are only separated from each other by networks of collagen and elastic fibers. The tapetal rods are bound by unit membranes and contain an electron dense core which, during the early postnatal weeks, exhibits a periodic cross-striation (100 Å). The tapetal rods increase in number and length during the first four weeks post partum; by the end of the fourth week, they occupy the whole cytoplasm of the tapetal cells. Parallelly arranged rods are grouped into individual bundles coursing inside the cytoplasm in different directions. Thereafter, the tapetal rods increase in thickness and their cross-striation becomes obscured by an electron dense material. This development of the tapetal rods closely resembles that of melanosomes. Thus the tapetum lucidum cellulosum can be regarded as a compact tissue made up of modified extracutaneous melanocytes.
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  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Anatomy and embryology 143 (1974), S. 127-134 
    ISSN: 1432-0568
    Keywords: Reticular formation ; Crossed connections ; Autoradiography ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Injection of radioactive leucine in various regions of the brain stem reticular formation has revealed the presence of ample crossed reticulo-reticular connections in the cat. The terminal area for the crossed fibers are almost mirror images of the injected sites. The findings made is another example that hitherto unknown fiber connections can be demonstrated by axoplasmic protein tracing.
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Anatomy and embryology 146 (1974), S. 1-20 
    ISSN: 1432-0568
    Keywords: Placenta ; Cat ; Differentiation ; Function ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Résumé L'ultrastructure du labyrinthe de placenta de chatte a été étudiée du 45e au 63e jour de gestation. Cette formation endothéliochoriale est composée: d'un endothélium maternel hypertrophié et de cellules géantes déciduales; d'une couche de «substance inerte interstitielle»; du trophoblaste constitué d'une assise syncytiale continue (syncytiotrophoblaste) et d'une assise cellulaire discontinue (cytotrophoblaste); d'un endothélium foetal accompagné de son environnement mésenchymateux. Les capillaires foetaux envahissent progressivement le syncytiotrophoblaste. L'hypertrophie de l'endothélium maternel diminue en fin de gestation; de ce fait la distance, séparant le sang maternel du sang foetal, peut atteindre en certains points 2 μ. L'endothélium maternel, le syncytiotrophoblaste et l'endothélium foetal présentent des signes ultrastructuraux d'un rôle de transfert. La «substance inerte inerte interstitielle», qui sépare les tissus d'origine maternelle des tissus d'origine foetale, est constante mais d'épaisseur variable; elle est spécifique des structures endothéliochoriales. Les cellules géantes déciduales, dont le nombre diminue en fin de gestation comportent parfois un ou plusieurs «corps glycogéniques». Le syncytiotrophoblaste, siége d'activité de biosynthése de stéroïdes, est riche en ergastoplasme, ce qui autorise à postuler la synthése d'hormones protéiques.
    Notes: Summary The ultrastructure of feline placental labyrinth has been studied from the 45th to the 63rd day of gestation. The endotheliochorial structure is composed of: a thick hypertrophied maternal endothelium with giant decidual cells; an “interstitial inert substance”; a continuous syncytial layer (syncytiotrophoblast) and a discontinuous cellular layer (cytotrophoblast) of trophoblast; and a thin foetal endothelium with its surrounding mesenchyme. Foetal capillaries increasingly invade the syncytiotrophoblast. Maternal endothelial hypertrophy is reduced in the last days of gestation. Thus the interval between maternal and foetal bloods may in some areas become 2 μ, in late pregnancy. Foetal endothelium, syncytiotrophoblast, and maternal endothelium demonstrate ultrastructural features of transfer function. The “interstitial inert substance”, which separates maternal from foetal tissue was always evident though with variable thickness. The giant decidual cells which are reduced in late pregnancy, show one or several “glycogen bodies”. The syncytiotrophoblast, where some steroïd biosynthesis has been demonstrated, has an extensive rough endoplasmic reticulum suggestive of protein hormone synthesis activity.
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  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Experimental brain research 19 (1974), S. 507-521 
    ISSN: 1432-1106
    Keywords: Cat ; LGN ; Transients ; Antagonistic inhibition ; Sensory storage
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Neuronal responses to interruptions of light stimuli were studied in 58 X-type and 7 Y-type LGN relay cells with intra- and extracellular recording techniques. The responses to interruption were then compared with responses to either appearing or disappearing light stimuli which had the same luminance and size as the interrupted stimulus. The extent to which responses to interruption differed from those to appearance and disappearance was studied as a function of the interstimulus interval (ISI), the duration of the stimulus before the interruption (t1) and after the interruption (t2). Responses to stimuli appearing after interruptions of up to 500 msec were weaker than those to appearance and disappearance. This difference decreased with increasing ISI. The difference between responses to appearance and interruption increased as t2 decreased, and decreased as t1 decreased. The reverse was true for the difference between responses to disappearance and interruption. Stimulation of the mesencephalic reticular formation consistently reduced the difference between responses to appearance and disappearance compared with those to interruption for all stimulus conditions. These results are discussed in the context of the psychophysical study presented in the preceding paper. It is shown that the neuronal reactions are reflected in detail by the ability of humans to detect appearances and disappearances that occur during interruptions. EPSP sequences recorded from LGN relay cells and relay cell responses conditioned by reticular stimulation suggest that the differentiation of responses to interruption and change partially occurs already in the retina. This differentiation is subsequently enhanced by antagonistic inhibition in the LGN. It is proposed that these inhibitory interactions at peripheral sites of the visual pathway store visual information and serve to reduce the redundancy of responses to short interruptions of the visual input. Centrifugal modulation of LGN inhibition is proposed to control the trade off between temporal integration and temporal resolution.
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  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Experimental brain research 19 (1974), S. 467-477 
    ISSN: 1432-1106
    Keywords: Suprasylvian gyrus ; Cat ; Single neurons ; Eye movements ; Direction sensitivity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 270 single neurons from the anterior part of the middle suprasylvian gyrus (AMSS) were recorded in awake and non-paralyzed cats (Chronic preparation). 10% were unresponsive to visual stimulation, the remainder reacted well to moving visual stimuli. Half of the units tested were directionally selective. Horizontal, or downward preferred directions predominated. Most neurons were relative insensitive to changes of shape, orientation, contrast, and velocity of the visual stimulus. Some neurons preferred rapid (100°/sec) jerky movements, others required complex motions of irregular shapes, a few strongly preferred objects moving towards the animal in the midsagittal plane. 40% of neurons yielded phasic On-Off reaction to flashing stationary spots. Habituation to repeated stimulation was a common feature and occured in 50% of AMSS neurons. In 19% of neurons tested the discharge rate was not affected by saccadic eye movements, when the animal faced a patterned background. Among the remainder two types of saccade associated responses could be distinguished. Type I discharged prior to or simultaneously with the onset of saccades. This early response was usually associated with saccades of particular directions. Saccades in total darkness yielded weaker and less consistent responses. Type II discharged subsequent to the onset of the saccades after a latency of 40 msec (type IIa), 40–80 msec (type IIb) and 80 msec (type IIc). Responses of type IIa are probably consequences of the retinal effects of eye movements. The saccade associated responses of type Ia, IIb and IIc are tentatively interpreted as results of an eye movement-synchroneous subcortical input, which facilitates transmission in AMSS neurons. Presaccadic facilitation, which generates type Ia responses, may be functionally related to shifts of attention prior to eye movements. It is suggested that postsaccadic facilitation, which underlies the reactions of type IIb and IIc, may be a correlate of visual attention during the fixation period.
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  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Experimental brain research 20 (1974), S. 125-134 
    ISSN: 1432-1106
    Keywords: Somato-sympathetic reflexes ; Cutaneous and muscle postganglionic neurones ; Noxious stimulation of skin ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. Somomato-sympathetic reflexes in postganglionic neurones to skin and muscle induced by noxious stimulation of skin were studied in cats anaesthetized with chloralose. The reflexes were elicited by mechanical damaging stimuli and by temperature stimuli of more than 45°C. 2. In most cutaneous units the spontaneous activity was depressed during noxious stimulation of skin. Some cutaneous units were excited or showed mixed responses. The depression of the spontaneous activity was maximal from the skin area which was innervated by the cutaneous postganglionic neurones and much weaker or not elicitable from other skin areas. 3. Most muscle units were excited during noxious stimulation of skin. This excitation could be elicited from all over the body surface. 4. The effective cutaneous afferent fibres which are involved in these reflexes are the Group III axones which are excitable by mechanical damaging stimuli and the Group IV axones which are excitable by mechanical damaging and/or by thermal noxious stimuli. 5. These investigations reveal that the somato-sympathetic reflexes have opposite organization in cutaneous and muscle postganglionic fibres. The reflex patterns are discussed in relation to a possible central organization of the sympathetic nervous system.
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  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Experimental brain research 20 (1974), S. 297-302 
    ISSN: 1432-1106
    Keywords: Cat ; Selective rearing ; Maturation ; OKN ; Perception of motion
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. Kittens reared in the dark from birth were exposed one hour a day between the 4th and the 10th week of age, to a visual environment which consisted exclusively of vertical edges moving horizontally at a constant speed, and always in the same direction. Total exposure time varied between 10 and 60 hours. 2. At the 12th week of age, optokinetic nystagmus (OKN) in response to displacements of the visual field, was tested. Displacements in the direction that the kittens had experienced during the exposure period elicited immediately an OKN, the frequency of which was related to the speed of the moving pattern. Displacements in the opposite direction elicited a poorer response, only for slowly moving edges. When the speed of the displacement was increased, OKN failed to adapt and finally disappeared. 3. These results suggest the existence, in this type of visuomotor behavior, of a component built up by early visual experience (adaptative component) overlying another component pre-existing visual experience (pre-programmed component).
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  • 9
    Electronic Resource
    Electronic Resource
    Springer
    Experimental brain research 21 (1974), S. 67-82 
    ISSN: 1432-1106
    Keywords: Sensory transmission ; Lateral geniculate nucleus ; Visual cortex ; Attentive behaviour ; Vigilance ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The behaviour of 6 cats was studied in a vigilance task. Each cat was trained to press a pedal on the floor of a training box. A waiting interval of fixed (FI) or variable (VI) duration then followed, after which a stimulus (S), a spot of light or a tone, was presented for a short period of time. The cat gave a correct response if, during this time, it pressed a panel. The animal was then rewarded with food. When an experiment had been completed using one S the cat was trained to respond to the other. The latency of response following the onset of S was measured for each waiting interval in the VI schedules. It was found that the longer latencies were associated with the shorter waiting intervals; that is, the cats responded more quickly to S as expectancy increased. Between the time the pedal and pand were pressed the optic tract (OT) was shocked not more than once and the response of the LGN and visual cortex recorded. The time at which the shock was delivered varied from 1 trial to the next. The responsiveness of the LGN and visual cortex did not vary during the waiting interval in either of the FI schedules or in the VI schedule in which S was a spot of light. However, in the VI schedule in which S was a tone, the responsiveness of the visual cortex to the thalamocortical input declined as the length of the waiting interval increased. No changes were observed at the LGN or in the presynaptic cortical response. These results contrast with those observed during changes in the level of arousal as assessed by the ECoG. When the ECoG passed from the synchronised to the desynchronised state there was an increase in the amplitude of the postsynaptic LGN response to the OT shock, but no change in the responsiveness of the cortex to the increased thalamocortical input. These changes in transmission in the visual pathways are discussed in relationship to the animal's behaviour and to the inferred state of attention.
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  • 10
    Electronic Resource
    Electronic Resource
    Springer
    Experimental brain research 21 (1974), S. 139-154 
    ISSN: 1432-1106
    Keywords: Electrotonic coupling ; Antidromic responses ; Abducens motoneurone ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The electrical stimulation of the abducens nerve provokes the classical true antidromic invasion of the abducens motoneurone and a depolarization which is often capable of generating full action potentials in the impaled motoneurone. Experiments studying these depolarizations suggest the existence of electrotonic coupling between the abducens motoneurones of the cat. Intracellular activity of the abducens motoneurones was recorded following intracellular stimulation of the impaled neurone and antidromic stimulation of the abducens nerve. Collision between the outgoing action potential and the antidromic volley differentiated the true antidromic spike from the depolarizations which can induce or not action potentials. The latency of the depolarization ranged between 100 and 1200 μsec. Collision demonstrated that the depolarization and the true antidromic action potential have an independent origin. The depolarizations and action potentials which are not conveyed to the motoneurone by its own axon are interpreted to be generated by electrotonic coupling.
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  • 11
    Electronic Resource
    Electronic Resource
    Springer
    Experimental brain research 21 (1974), S. 315-336 
    ISSN: 1432-1106
    Keywords: Visual cortex (area 17) ; Cat ; Columnar organization ; Retino-cortical scatter ; Intracortical connections
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. Responses of cortical cells in the cat's area 17 (central and paracentral area), recorded successively during electrode penetrations perpendicular to the surface, were averaged (PSTH). All cells recorded during one penetration were stimulated with the same stimulus, a slowly moving light or dark slit oriented optimally for the first cell recorded. Comparisons between successively recorded cells were completed by simultaneous recordings from two neurones with the same microelectrode tip. Eye movements as an error were excluded by simultaneous recording of a geniculate cell throughout a cortical penetration. 2. The centers of excitatory receptive fields (ERFs) of simultaneously or successively recorded cells during a penetration may be separated by more than 4°. The mean scatter around a column average is 0.81±0.99° in both directions. The scatter is independent of the recording depth. Whereas the optimal orientation of cells recorded during one penetration was generally similar, the optimal direction (forward and backward movement of an optimally oriented stimulus) was variable. 3. The ERF diameters as determined from the PSTH were between 〈0.5° and 7.5°. During each penetration, cells with small (up to 3.0°) and large (〉3.0°) ERFs could be discriminated. The inhibitory fields (determined with the conditioning method of Bishop, Coombs and Henry, 1971) were between 2.0 and 8.5° along both the optimal and the non-optimal orientation axis of a cell. The borders of inhibitory fields of cells collected during one penetration were also scattered though overlapping. 4. Response analysis of simultaneously and successively recorded cells with different stimuli indicated that, in spite of considerable ERF-overlap, cells with small ERFs had separate excitatory inputs and that intracortical excitatory connections between cells recorded during one penetration were improbable. 5. The ERFs of cells with large ERFs covered a field approximately corresponding to the fields of cells with small ERFs. But a convergent input from many small ERF cells to single large ERF cells was excluded because of the incompatible functional properties of both types of cells, which correspond to some extent to simple and complex cells respectively. 6. It is concluded that cells within cortical cylinders are not connected through excitatory contacts with each other and that most cells in area 17 are excited by individual excitatory geniculate or cortical inputs. Inhibitory connections seem to be the most important intracortical connections. 7. In an Appendix it is shown that anatomical and physiological data do not support significant excitatory convergence of specific geniculate afferents on cortical neurones.
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  • 12
    Electronic Resource
    Electronic Resource
    Springer
    Experimental brain research 21 (1974), S. 433-439 
    ISSN: 1432-1106
    Keywords: Superior colliculus ; Visual cortex ; Layer V-pyramids ; Clare Bishop area ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Stereotaxic injection of horseradish peroxidase into the superior colliculus produced retrograde labelling of layer V pyramides in the Clare Bishop area and the lateral bank of the suprasylvian sulcus, in area 17,18 and 19. Single labelled cells were also found scattered in the splenial, the suprasplenial, the lateral and the suprasylvian gyri. In the cruciate sulcus no labelled cells were observed. Autoradiographically, the lateral bank of the suprasylvian sulcus was also shown to give rise to fibres to the superior colliculus.
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  • 13
    ISSN: 1432-1106
    Keywords: Lateral reticular nucleus ; Bilateral ventral flexor reflex tract (bVFRT) ; Spino-reticulo-cerebellar path ; Cerebellum ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. Neurones in the lateral reticular nucleus (LRN) activated by the bilateral ventral flexor reflex tract (bVFRT-LRN neurones) were identified by their responses to stimulation of fibres descending in the contralateral ventral quadrant of the spinal cord which activate the bVFRT neurones monosynaptically. 2. Eighty-eight of the 134 bVFRT-LRN neurones encountered could be antidromically activated at a low stimulus strength from small areas of the cerebellar surface assumed to represent cortical termination points. 3. The bVFRT-LRN neurones occurred throughout the parvi- and magnocellular parts of the LRN and terminated bilaterally in the anterior lobe and sparsely in the ipsilateral paramedian lobule and in the pyramis. 4. The responses evoked in the bVFRT-LRN neurones on stimulation of the contralateral ventral quadrant at C5 and L1 made it possible to estimate the approximate spinal level from which the bVFRT fibres originated. On this basis the bVFRT-LRN neurones were divided into cervical, thoracic, and lumbar groups receiving bVFRT afferents from mainly one spinal level and a convergence group receiving bVFRT afferents from several levels. 5. The different bVFRT-LRN groups received excitation from different combinations of nerves in the four limbs. 6. The cervical, thoracic and lumbar groups of the bVFRT-LRN neurones occurred in successively more ventrolateral portions of the LRN. 7. The cervical, thoracic and lumbar groups of the bVFRT-LRN neurones terminated in successively more rostral areas of the anterior lobe. 8. The organization of the bVFRT-LRN path is compared with that of the ventral and rostral spinocerebellar tracts. The possible function of the bVFRT-LRN path is discussed.
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  • 14
    ISSN: 1432-1106
    Keywords: Reticular formation ; Superior colliculus ; Cat ; Experimental anatomy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Following altogether 18 stereotactically placed lesions of different location and size in the superior colliculus the efferent fibres to the RF and their distribution were traced in silver impregnated, approximately serial sections (Nauta and Fink and Heimer methods), cut in the transverse, horizontal or sagittal plane. The projection to the mesencephalic RF was found to be almost completely ipsilateral, that to the pontomedullary RF largely contralateral. In the mesencephalic RF the fibres end in its dorsal half approximately. In the pons and medulla they supply only the medial 2/3 of the main RF, with two distinct maxima within the total field of termination. One maximum covers the rostral part of the nucleus reticularis gigantocellularis and the adjoining part of the nucleus reticularis pontis caudalis, the other occupies the rostralmost part of the latter and the caudal part of the nucleus reticularis pontis oralis. Of the precerebellar reticular nuclei the contralateral nucleus reticularis tegmenti pontis receives a distinct component of tectal fibres in a small area dorsomedially. Some fibres end in a restricted part of the nucleus reticularis lateralis and in the paramedian reticular nucleus. The tectoreticular projection appears to be organized according to the same principles as other afferents to the RF. In the main RF the areas of termination of the tectoreticular fibres coincide more or less with the areas of termination of corticoreticular, fastigioreticular and vestibuloreticular fibres. These common terminal areas are those which give off the bulk of reticulospinal fibres. Some functional implications of the pattern of organization in the tectoreticular projection are discussed.
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  • 15
    Electronic Resource
    Electronic Resource
    Springer
    Experimental brain research 20 (1974), S. 101-114 
    ISSN: 1432-1106
    Keywords: Size principle ; Motoneurons ; Cat ; Recruitment ; Neurophysiology
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Henneman et al. have shown that a wide variety of stimuli activate motoneurons in the order of their sizes, though some reversals occur. It is not clear which motoneurons should be included in the “pool” from which recruitment by size takes place. The “pool” may consist of 1. all the motoneurons to a given muscle 2. all the motoneurons in a given ventral root or 3. all the motoneurons activated by a given stimulus. We have examined recruitment in the pool of fibers to a given muscle. A variety of mechanical stimuli to cat's legs were used to elicit bursts of activity in gastrocnemius motor units. In 30% of pairs of units, one unit had a consistently lower threshold, i.e. it always began and ended a burst. In the other 70%, either unit could start or end a burst. For 48% of motor unit pairs recorded in either the medial or lateral gastrocnemius, each unit of the pair had runs of firing of at least 10 spikes while the other was totally inactive. By the same criterion, 23% of pairs of temporalis units showed differential activity. During spontaneous breathing there was no consistent recruitment order in 24% of pairs of units in throat respiratory muscles. These data indicate that reversals of recruitment order are relatively common for motoneurons innervating the same muscle. We discuss the possibility that size principle may hold for motoneurons in a single ventral rootlet whose somas are anatomical neighbors (even though they innervate different muscles), but not for motoneurons that are anatomically distant in the cord (even though they innervate the same muscle).
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  • 16
    Electronic Resource
    Electronic Resource
    Springer
    Experimental brain research 20 (1974), S. 135-143 
    ISSN: 1432-1106
    Keywords: Cat ; Renshaw cell ; Antidromic activation ; Differential blocking
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Attempts were made to study differences in the relative effectiveness of different size ranges of motor axons to Renshaw cells by differential blocking of larger fibers of the gastrocnemius nerve in cats anesthetized with Nembutal. 1. Differential blocking of larger fibers in the nerve was successfully obtained by applying trapezoid wave current to the nerve. 2. It was shown that more than half (58.1%) of the Renshaw cells receive homogeneous inputs from a motor axon collaterals, 25.8% of the cell receive collateral inputs from a certain group of fibers, and 12.5% of the Renshaw cells were activated by “γ range” fibers.
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  • 17
    Electronic Resource
    Electronic Resource
    Springer
    Experimental brain research 20 (1974), S. 115-123 
    ISSN: 1432-1106
    Keywords: Somato-sympathetic reflexes ; Postganglionic fibres to skin and muscle ; Natural stimulation of skin ; Hair-follicle receptors ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. Somato-sympathetic reflexes in postganglionic neurones to hairy skin and to muscle produced by mechanical non-noxious stimulation of skin were studied in cats anesthetized with chloralose. Most of the postganglionic fibres investigated were spontaneously active and had presumably vasoconstrictor function. 2. In 60% of the cutaneous postganglionic neurones stimulation of hairs induced predominantly excitation. This excitation was mostly followed by a slight depression of the spontaneous activity. In 30% of the neurones the spontaneous activity was depressed or predominantly depressed by these stimuli. 3. In most muscle postganglionic neurones the spontaneous activity was depressed by stimulation of hairs. 4. In both types of neurones the reflexes were produced by activity in hair follicle receptors with Group II afferents. Hair follicle receptors with Group III afferents most probably also contributed to this effect. Except for a slight depression of the spontaneous activity in some cutaneous postganglionic neurones by slowly adapting receptors, mechanical stimulation of other types of receptors with Group II afferents had no effect on the postganglionic neurones. 5. Reflexes in postganglionic neurones could be elicited by stimulation of hairy skin all over the body surfaces.
    Type of Medium: Electronic Resource
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  • 18
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    Experimental brain research 20 (1974), S. 273-283 
    ISSN: 1432-1106
    Keywords: Vestibular nuclei ; Thalamic projections ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Electrolytic lesions were placed into the left vestibular nuclei of 22 adult cats. Silver impregnation for degenerated terminal fibres of serial sections revealed the existence of a relay of the corticopetal vestibular pathway in the contralateral thalamus. Its main afferent fibres originate in the superior and medial vestibular nuclei. By crosschecking the results it was possible to demarcate a focus of vestibular projections in the ventro-caudal part of the thalamus, situated between the centre median, the ventro-basal group and the caudal segment of the ventro-lateral nucleus. The direct ascending afferents of this focus are relatively few in number. The functional significance of this vestibular relay with regard to the proprioceptive influx passing through this region of the thalamus is open to discussion.
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  • 19
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    Experimental brain research 20 (1974), S. 285-296 
    ISSN: 1432-1106
    Keywords: Ampullary nerve ; Cat ; EPSP ; IPSP ; Vestibular neuron
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The six ampullary nerves in both labyrinths were separately stimulated by electric pulses in anesthetized cats. Resulting responses in neurons in the vestibular nuclei were recorded intracellularly. Almost all the vestibular neurons showed an EPSP in response to stimulation of the ipsilateral ampullary nerve. These neurons were subclassified as A-, L-, and P-neuron receiving specific projections from the anterior, lateral and posterior canal, respectively. Three fourths of the vestibular neurons recorded from received an IPSP in response to stimulation of the contralateral ampullary nerve. Plane-specific contralateral inhibition was found in most of vestibular neurons; i.e. A-, L-, and P-neuron received IPSP from the contralateral posterior, lateral, and anterior ampullary nerve, respectively. Approximately two thirds of vestibular neurons exhibiting the plane-specific inhibition were recorded in the medial vestibular nucleus. A collision test of impulses in primary afferent fibers were performed during recording of ipsilateral EPSPs produced by strong stimulation of more than one ampullary nerve. No positive evidence was provided for the existence of neural convergence on single vestibular neurons from different ampullary nerves on the same side. It is suggested that the plane-specific contralateral inhibition increase the sensitivity of vestibular neurons during head rotation.
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  • 20
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    Experimental brain research 20 (1974), S. 347-362 
    ISSN: 1432-1106
    Keywords: Vestibular nuclei ; Tilt response ; Sinusoid ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Extracellular recordings were made in the lateral and inferior vestibular nuclei of decerebrate, unanesthetized cats. The firing patterns of single units were studied using small amplitude sinusoidal roll tilts of from 0.01 Hz to 1.0 Hz. Three-fourths of the tilt-sensitive units showed greater modulation of their firing rates as the frequency of the sinusoidal tilt was increased. The responses of cells in both nuclei were similar. These responses were virtually unchanged in cats with chronically plugged semicircular canals, indicating a probable otolith origin for the dynamics of the tilt response.
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  • 21
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    Experimental brain research 20 (1974), S. 363-374 
    ISSN: 1432-1106
    Keywords: Pain ; Somatosensation ; Cerebral cortex ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The experiment examines the role of the cerebral cortex in regulating responses to noxious stimulation by studying the effects of cortical ablations in cats on escape from electric shock applied to the foot pads. The latency of escape as a function of shock intensity was measured before and after bilateral ablations of various portions of the cat's somatosensory cerebral cortex. Ablations of the second somatosensory cerebral cortex significantly increased the escape response threshold. If the sulci bordering this region were included in the ablation, the threshold increase was greater and longer-lasting. Ablations of the primary somatosensory cortex increased latencies at most intensities of electric shock, but did not change the response thresholds. Ablations of both primary and second somatosensory cortex increased response thresholds and response latencies. None of these ablations altered the responses, however, if the cat had been overtrained for six to seven months prior to surgery. The results suggest that the second somatosensory region and the sulci bordering the second somatosensory region in the cat cerebral cortex are involved in responses to noxious stimulation.
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  • 22
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    Experimental brain research 21 (1974), S. 45-66 
    ISSN: 1432-1106
    Keywords: Visual cortex ; Efferent cells ; Non-efferent cells ; Synaptic connection ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Neuronal connections in the visual cortex of cat (areas 17 and 18) were studied with intracellular recording and electrical stimulation techniques under Nembutal anaesthesia. Four types of axonal projection were seen; 1. association efferent cells projecting to adjacent cerebral cortex on the ipsilateral side, 2. commissural efferent cells to visual cortex on the contralateral side, 3. corticofugal efferent cells to the ipsilateral lateral geniculate body and superior colliculus, and 4. non-efferent cells whose projection is confined within the visual cortex. Both association and commissural efferent cells were located in layer III, corticofugal efferent cells in layer V and non-efferent cells in layers II–VI. Upon these cells two types of synaptic actions were exerted by the specific visual afferents that originate from the lateral geniculate body; 1. type I, monosynaptic excitation plus disynaptic inhibition and 2. type II, disynaptic excitation plus trisynaptic inhibition. Type I effects were found in layers III–V, and type II in layers II and VI. In the border region between areas 17 and 18 monosynaptic excitation and disynaptic inhibition were produced also by the commissural efferents originating from the contralateral visual cortex. On the basis of these results, a possible neuronal circuitry in the visual cortex is postulated.
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  • 23
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    Experimental brain research 21 (1974), S. 473-486 
    ISSN: 1432-1106
    Keywords: Lateral reticular nucleus ; Reticulocerebellar projection ; Cerebellum ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. The areas of the cerebellar cortex receiving fibres from the mLRN (major portion of the lateral reticular nucleus comprising its parvi- and magnocellular parts) were determined by identifying the low-threshold spots on the cerebellar surface from which 286 mLRN neurones could be antidromically activated. 2. The mLRN fibres terminate bilaterally in the anterior lobe and pyramis, and ipsilaterally in the paramedian lobule. Some fibres terminate also in the rostral part of lobule VI but hardly any in other parts of the cortex. It follows that the mLRN projects almost exclusively to the classical spinal receiving areas. 3. Neurones in the parvi- and magnocellular parts project to similar cortical areas. 4. Two regions in the mLRN were distinguished on the basis of their different projection areas. Region A, a dorsolateral portion of the magnocellular part, projects to the ipsilateral parts intermedia of the anterior lobe and the ipsilateral paramedian lobule. Region B, a ventral portion of the parvi- and magnocellular parts, projects bilaterally to the pars intermedia and vermis of the anterior lobe and sparsely to the pyramis. 5. Neurones throughout the parvi- and magnocellular parts receive monosynaptic excitation from fibres ascending in the ventral part of the ipsilateral lateral funiculus.
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  • 24
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    Experimental brain research 21 (1974), S. 501-513 
    ISSN: 1432-1106
    Keywords: Lateral reticular nucleus ; Spinoreticular tract ; Cerebellum ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. The activation of neurones in the mLRN (major portion of lateral reticular nucleus comprising its parvi- and magnocellular parts) by two spinal tracts ascending through the ventral part of the lateral funiculus has been studied by recording from 277 neurones of which 187 could be antidromically activated by stimulation of the cerebellar surface. Forty-eight % of the neurones were activated by the bVFRT and described in a previous paper (Clendenin et al., 1975b) and 12% were activated by a previously unknown tract denoted the ipsilateral forelimb (iF) tract and described in the present paper. 2. The iF-tract is activated by stimulation of nerves in the ipsilateral forelimb only. The response consists of a train of impulses with a high initial frequency and an almost constant latency. Cutaneous afferents and high threshold muscle afferents contribute to the excitation which is mediated by interneurones. 3. The responses to stimulation of peripheral receptors were weak and difficult to classify. 4. The iF-tract activates neurones in the dorsolateral portion of the magnocellular part of the mLRN which projects to the ipsilateral pars intermedia of the anterior lobe and the ipsilateral paramedian lobule. 5. The possible information carried by the iF-tract is discussed.
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  • 25
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    Experimental brain research 19 (1974), S. 36-60 
    ISSN: 1432-1106
    Keywords: Cerebellar nuclei ; Motor cortex ; Evoked potentials ; Topographical organization ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. A topographical study of cerebello-cortical relations was conducted in cats anesthetized with chloralose. The potentials evoked by punctate stimulation of the cerebellar nuclei were recorded at various sites in the contralateral motor cortex. A map of the cortical responses obtained by stimulating each of the cerebellar nuclei was established. For this purpose, the stimulation thresholds as well as the response amplitudes, polarity and latency were noted. 2. Local stimulation of each cerebellar nucleus evoked responses in particular regions of the contralateral motor cortex. When a stimulus was applied to the interpositus nucleus, short latency responses were recorded in the lateral part of the area 4. Dentate nucleus stimulation induced short latency responses in the medial part of area 4 and in area 6. Furthermore, late responses were also recorded laterally in area 4. 3. The interpositus nucleus was found to project to the portion of motor cortical area controlling the distal forelimb with only a fast conducting pathway. The fastigial nucleus seems to be connected with proximal and axial motor areas. The projection system of the dentate nucleus appears to have a temporal organization: a fast conducting pathway was found to project to the axial and proximal motor area while a slower one seems to transmit impulses to the motor area of the forelimb extremity. 4. The functional aspects suggested by the temporal organization of the cerebellocortical inputs and the distribution of each nucleus projections on the motor cortical areas are discussed.
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  • 26
    ISSN: 1432-2013
    Keywords: Splanchnic Afferents ; G.I. and Peritoneal Receptors ; Cortical Projections ; Microelectrode Technique ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The experiments were performed on cats anesthetized with chloralose or Nembutal. The unitary activity of cortical neurons was recorded in the SI and SII areas by means of extracellular glass microelectrodes. The neurons showed frequently a spontaneous discharge (irregular or regular tonic discharge bursts of spikes). The electrical stimulation of contralateral splanchnic nerves produced different effects on a great number of the neurons: 1. early short activation, 2. late activation, 3. early and late complex activation, 4. partial or total inhibition of the spontaneous activity. These effects were obtained in the different cortical layers. Similar results have been observed by mechanical stimulation of the splanchnic receptors located in the gastro-intestinal tract and in the peritoneum. However in this case, the duration and the amplitude of inhibition and activation were generally weaker.
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  • 27
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    Cell & tissue research 149 (1974), S. 121-135 
    ISSN: 1432-0878
    Keywords: Astrocytic membranes ; Cat ; Orthogonal particle-complexes ; Freeze-etching
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Fixed and unfixed astrocytic membranes from the CNS of the cat were studied by means of the freeze-etching technique. A variable number of gap junctions was detected in astrocytic membranes. They are characterized by the well known hexagonal composition of their subunits. Besides this type of highly ordered membrane-bound particles, a second one was found. It is composed of four single particles (diameter 5 nm) which form an orthogonal subunit with a side length of about 10 nm. These membrane-associated orthogonal particle complexes (MOPC) could be observed in different stages of aggregation and expansion. They reveal an accumulation in membranes of the marginal glia layers and in the perivascular astrocytic end-feet. Unfixed, glycerol treated membranes, however, do not show these structures. After glycerol treatment of the unfixed membranes by immersion, the MOPC disintegrate to single particles which form clusters of various extension. The clustering phenomenon is dependent on the length of the time of exposure to glycerol. Shortening of the glycerol treatment by intravasal perfusion of the cryoprotectant agent causes an decrease of the clusters. Fragments and transient forms of the MOPC become visible. By variation of different physico-chemical parameters of the washing solution a similar effect on the MOPC was not achieved. The discussion deals with probable functional aspects of the MOPC. They are considered to act as membrane-bound functional multienzyme complexes which a) might play a role in mediating transmembrane passage of metabolites, or b) are essential for CSF control mechanisms, or c) have a functional relation to the nexus.
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  • 28
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    Cell & tissue research 151 (1974), S. 489-498 
    ISSN: 1432-0878
    Keywords: Limbic system ; Cat ; Amygdaloid body ; Light and electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The present study was undertaken to re-examine the central nucleus of the cat in Nissl stained sections, to describe its fine structural characteristics, and to compare the lateral subdivision of this nucleus with the putamen. In Nissl preparations, it was observed that the lateral subdivision of the central nucleus contains a fairly homogeneous population of small cells while the putamen contains both small and large cells. It is the presence of a few large cells at the lateral periphery of the lateral part of the central nucleus that makes the boundary between the two nuclei indistinct. Examination of the fine structure of the medial and lateral subdivisions of the central nucleus revealed the presence of many boutons containing flattened vesicles and fewer with spheroid vesicles. In contrast, most of the boutons in the putamen have spheroid vesicles. It is concluded that the lateral subdivision of the central nucleus may be distinguished from the putamen, except at its most lateral border, by its homogeneous population of small cells and its many boutons containing flattened vesicles.
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  • 29
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    Cell & tissue research 150 (1974), S. 143-145 
    ISSN: 1432-0878
    Keywords: Arteria centralis retinae ; Cat ; Innervation ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Terminal axons emerging from the inner plexiform layer of the cat retina reach the wall of the arteria centralis retinae, as revealed by electron microscopy. Numerous unusually large dense core vesicles (about 1000 Å in diameter), of different electron densities, occur in the varicosities of these axons. These observations may be compatible with the idea of an innervation of the central artery of the retina which is non-autonomic, possibly intrinsic in nature.
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  • 30
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    Cell & tissue research 151 (1974), S. 499-508 
    ISSN: 1432-0878
    Keywords: Limbic system ; Cat ; Amygdaloid body ; Hypothalamus ; Stereotaxic lesions ; Light and electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In order to determine the origin of the hypothalamo-amygdaloid connections in the cat, small lesions were placed at various rostro-caudal levels of the hypothalamus. The animals were sacrificed after a period of 4, 8 or 11 days and the brains stained with the Nauta (1957), Fink and Heimer (1967) or Wiitanen (1969) method for the demonstration of degenerating axons and their terminals. It was observed that the anterior hypothalamic nucleus sends a small projection to the medial subdivision of the central nucleus and to the basal and lateral nuclei of the amygdala. The lateral preoptic area sends a larger projection to the anterior amygdaloid area, both subdivisions of the central and basal nuclei, and to the lateral and medial nuclei. No degeneration was observed in the amygdala following lesions in the medial preoptic area, the ventromedial nucleus or the lateral hypothalamic area caudal to the anterior hypothalamic area. In a series of animals with lateral preoptic lesions, the site of termination of degenerating boutons on neurons of the amygdaloid nuclei was determined and the course of the degenerative process followed over a period ranging from 2 to 15 days. Many of the boutons, especially in the earlier stages of degeneration, appeared to be of the B3 type, containing flattened vesicles and forming symmetrical synaptic contacts with dendrites or somata. With longer post-operative survival times, however, they became increasingly electron dense and shrunken, so that the bouton type could not be determined.
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  • 31
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    Cell & tissue research 148 (1974), S. 577-586 
    ISSN: 1432-0878
    Keywords: Node of Ranvier ; Axonal-glial junctions ; Cat ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The paranodal zone of myelinated nerve fibers from the CNS of cats has been studied by means of the lanthanum technique and after freeze-etching. Special interest was given to the axonal-glial zones of contact in this region. Examination of the membranes of the paranodal pockets and the axolemma revealed that the membrane thickenings which occur between the adjacent membranes actually consist of bands. The bands show a specific pattern of diagonal running subunits 10 nm apart. These substructures of the axonal side of the membrane contacts protrude outwards, i.e. towards the glial membrane, where they fit into depressions on the glial membrane surface. This arrangement in form of a “zip-fastener” makes the whole structure very flexible. The subdivision of the bands was identified with both techniques. The different membrane aspects obtained by the freeze-etching technique are discussed in respect to the splitting theory, and a hypothetical model of this membrane specialization is presented.
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  • 32
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    Cell & tissue research 148 (1974), S. 565-576 
    ISSN: 1432-0878
    Keywords: Central myelin ; Junctions ; Cat ; Freeze-etching ; Lanthanum impregnation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In male and female cats central myelin was studied using the freeze-etching technique, and after impregnation with lanthanum as a tracer. The freeze-fractured and etched faces of the myelin reveal membrane formations which in many respects resemble tight junctions. The formations consist of parallel rows of particles on one half of the membranes matched by corresponding furrows on the other membrane half. These structures occur across the width of the myelin sheath and are most common in that part of the myelin underlying the external cytoplasmic loop. They are interpreted as correlates of the radial component of the i-line which occurs in cross-sections of central myelin after potassium permanganate staining. In the paranodal zone the lanthanum-impregnated myelin displays punctate fusions between the outer leaflets of the oligodendrocytic membranes. These findings strongly suggest that tight junctions are a common feature in the central myelin. The arrangement of the membrane fusion in relation to the elements of the lamellar complex and their functional significance is discussed.
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  • 33
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    Cell & tissue research 150 (1974), S. 409-423 
    ISSN: 1432-0878
    Keywords: Synaptic organization ; Trochlear nucleus ; Cat ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Two distinct types of neuron in the cat trochlear nucleus (one large, one small) are described, the α- and γ-motoneurons, respectively. Four types of terminals are observed which establish axo-dendritic synapses. Two of them (Types I and II) perform axo-somatic synapses as well. Terminals en passant (Types I and II) are predominant. The Type I terminal is long and slender with a characteristic distribution of the axoplasmic organelles and the unique feature of a relative narrowing of the synaptic cleft as compared to the width of the neighboring extracellular space. Its vesicle population is pleomorphic and a conspicuous glial barrier surrounds the synaptic zones. The Type II terminal differs slightly from Type I, revealing a wider synaptic cleft and lacking a characteristic distribution of the axoplasmic organelles. The type III terminal is rarely observed performing axo-somatic synapses, but is a common finding in the neuropil. Post-junctional dense bodies are often present in its axodendritic synapses. The Type IV nerve terminal performs axo-dendritic synapses and is characterized by a rich content of large granulated vesicles. Axo-axonal synapses are observed only very rarely. The synaptic organization of the feline trochlear nucleus is compared with the synaptic morphology of the oculomotor nuclei of inframammalian species (Waxman and Pappas, 1971). In addition to certain similarities (e.g., richness of synapses en passant), significant differences are encountered: the present study provides no morphological evidence for electrotonic transmission in the trochlear nucleus of cat.
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  • 34
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    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 406 (1974), S. 299-306 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: On Reactions of Bis(trifluoromethyl)diazomethane with SulfonylisocyanatesSulfonylisocyanates RSO2NCO (B = F, Cl, CF3) react with (CF3)2CN2 at 100-160°C to give l,2,3-oxathiazole-4-one-2-oxidesWhile the ring IIa is cleaved by methanol (formation of FSO2—NH—C(O)—C(CF3)2OH) with waterThe proton of the compound V might be substituted by metal atoms, especially the silver salt is suitable for the preparation of further 1,2,3-oxathiazoline-4-one-2,2-dioxides.
    Notes: Sulfonylisocyanate RSO2NCO (E = Cl, F, CF3) reagieren mit (CF3)2CN2 bei 100-160°C zu 1,2,3-Oxathiazol-4-on-2-oxidenWährend der Ring IIa mit Methanol gespalten wird (Bildung von FSO2—NH—C(O)— C(CF3)2OH), erhält man bei der Umsetzung mit WasserDas Proton dea Hydrolyseprodukts läßt sich durch Metallatome ersetzen, besonders das Silbersalz eignet sich zur Darstellung weiterer 1,2,3-Oxathiazolin-4-on-2,2-dioxide.
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  • 35
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    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 406 (1974), S. 307-311 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Preparation and Vibrational Spectrum of Tetra-thiomethyl-phosphoniuin-hexachloroantimonatePreparation, properties and vibrational spectrum of Tetra-thiomethyl-phosphonium-hexachloroantimonate are reported. The kind of bonding in the ion is brief discussed.
    Notes: Es wird über die Darstellung, Eigenschaften und Schwingungsspektren des Tetra-thiomethyl-phosphonium-hexachloroantimonats berichtet. Die Bindungsverhältnisse werden kurz diskutiert.
    Additional Material: 3 Tab.
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  • 36
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    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 407 (1974) 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 37
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Tricyclic Transition Metal Complexes with Ring Systems Containing Silicon: The Structures of Ni(C6H17N5S4Si2) und Co(C4H12N4S4OSi2)Crystals of Ni(C6H17N5S4Si2) 3 b are orthorhombic, space group Pbcn, with a = 10.341, b = 11,650, c = 14.163 Å and Z = 4 and crystals of Co(C4H12N4S4OSia) 4b are monoclinic, space group P21/c, with a = 7.304, b = 17.866, c = 11.805 Å, β = 100.88° and Z = 4. The structures have been determined by an X-ray crystallographic analysis and were refined to R = 0.060 for 3b and 0.114 for 4b. The two almost planar MN3S2 chelate rings per molecule intersect with an angle pf 16.2° in 3 b and 27.0° in 4 b. The six-membered rings containing silicon are puckered in such a way that both molecules exhibit (approximate) C2 symmetry.
    Notes: Der Komplex Ni(C6H17N5S4Si2) 3b kristallisiert in der orthorhombischen Raumgruppe Pbcn mit a = 10.341, b = 11.650, c = 14.163 Å und Z = 4 und der Komplex Co(C4H12N4S4OSi2) 4b kristallisiert in der monoklinen Raumgruppe P21/c mit a = 7.304, b = 17.866, c = 11,805 Å, β= 100.88° und Z = 4. Die Strukturen wurden röntgenographisch bestimmt und bis zu R = 0.060 bzw. 0.114 verfeinert. Die praktisch ebenen MN2S2-Chelatringe bilden Flächenwinkel von 16.2° in 3b und 27.0° in 4b. Die Silicium enthaltenden sechsgliedrigen Ringe sind derart gewellt, daß beide Moleküle die (angenäherte) Eigensymmetrie C2 aufweisen.
    Additional Material: 3 Ill.
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  • 38
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    Zeitschrift für anorganische Chemie 407 (1974), S. 13-22 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: On Novel Hexafluoro Rhodates(IV): AIIRhIVF6. (AII = Ba, Sr, Ca, Mg, Zn, Cd, Hg, Ni, Cu)We obtained hithertoo unknown BaRhF6 and SrRhF6 (both lemon yellow) of (hexag.) BaSiF6-Type [a = 7.379, c = 7.211Å bzw. a = 7.157, c = 6.948 Å] as well as CaRhF6 (light yellow) [a = 5.267, c = 14.612 Å], MgRhF6 (light yellow) [a = 5.027, c 13.511Å], ZnRhF5 (light yellow) [a = 4.996, c = 13.683 Å], CdRhF6 (light yellow) [a = 5.,128 c = 14.447 Å], HgRhF6 (orange) [a = 5.133, c = 14.676 Å], NiRhF6 (light brown) [a = 4.960, c = 13.514 Å] all of (hexag.) LiSbF6-type. The strukture of CuRhF6 (light brown) is yet unknown.
    Notes: Neu dargestellt wurden BaRhF6 und SrRhF6, beide zitronengelb, (hexag.) BaSiF6-Typ [a = 7,379, c = 7,211 Å bzw. a = 7,157, c = 6,948 Å] sowie CaRhF6 (hellgelb) [a = 5,267, c = 14,612 Å], MgRhF6 (hellgelb) [a = 5,027, c = 13,511 Å], ZnRhF6 (hellgelb) [a = 4,996, c = 13,683 Å], CdRhF6 (hellgelb) [a = 5,128, c = 14,447 Å], HgRhF6 (orange) [a = 5,133, c = 14,676 Å], NiRhF6 (hellbraun) [a = 4,960, c = 13,514 Å], alle (hexag.) LiSbF6-Typ. Von CuRhF6 (hellbraun) ist die Struktur bislang unbekannt.
    Additional Material: 4 Ill.
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  • 39
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    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 407 (1974), S. 305-312 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: On Hexafluoroferrates(III): Cs2TlFeF6, Cs2KFeF6, Rb2KFeF6, Rb2NaFeF6, and Cs2NaFeF6New prepared are the compounds Cs2TlFeF6 (a = 9.211 Å), Cs2KFeF6 (a = 9.041 Å), Rb2KFeF6 (a = 8.868 Å) and Rb2NaFeF6 (a = 8.46 4Å) all cubic Elpasolithes as well as Cs2NaFeF6 (Cs2NaCrF6-type, hexagonal with a = 6.281, c = 30.532 Å), all colourless. Cs2KFeF6 was measured magnetically (70-297,2 K). The spectra of reflection were measured (9000-36000 cm-1). The Madelung Part of Lattice Energy, MAPLE, is calculated and discussed.
    Notes: Neu dargestellt wurden Cs2TlFeF6 (a = 9,211 Å), Cs2KFeF6 (a = 9,041 Å), Rb2KFeF6 (a = 8,868 Å) und Rb2NaFeF6 (a = 8,464 Å) alle kubische Elpasolith-Vertreter, sowie Cs2NaFeF6 (Cs2NaCrF6-Typ, hexagonal mit a = 6,281, c = 30,532 Å) als farblose Pulver. Cs2KFeF6 wurde magnetisch vermessen (70 bis 297,2 K). Das Reflexionspektrum von FeF3 wurde gemessen (9000 bis 36000 cm-1). Der Madelunganteil der Gitterenergie, MAPLE, wird berechnet und diskutiert.
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  • 40
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 407 (1974), S. 313-318 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: New Elpasolithes with CoIII: Cs2KCoF6, Rb2KCoF6, Rb2NaCoF6 (with a Notice on Cs2NaCoF6)New prepared are the compounds Cs2KCoF6 (a = 8.979 Å), Rb2KCoF6 (a = 8.809 Å), Rb2NaCoF6 (a = 8.421 Å), all cubic Elpasolithes, as well as Cs2NaCoF6 (Cs2NaCrF6-type, hexagonal with a = 6.23, c = 30.32 Å) all of light blue colour. Cs2KCoF6 (72.7-299.7 K) and Rb2KCoF6 (71.4-298.0 K) have been measured magnetically. The Madelung Part of Lattice Energy (MAPLE) is calculated and discussed.
    Notes: Neu dargestellt wurden Cs2KCoF6 (a = 8,979 Å), Rb2KCoF6 (a = 8,809 Å), Rb2NaCoF6 (a = 8,421 Å), alle kubische Elpasolith-Vertreter, sowie Cs2NaCoF6 (Cs2NaCrF6-Typ, hexagonal mit a = 6,23, c = 30,32 Å) als hellblaue Pulver. Cs2KCoF6 (72,7 bis 299,7 K) und Rb2KCoF6 (71,4 bis 298,0 K) wurden magnetisch vermessen. Der Madelunganteil der Gitterenergie, MAPLE, wurde berechnet und diskutiert.
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  • 41
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 407 (1974), S. 319-326 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: On Chalkogenolates. LXVII. Glycolates of Alkali Metals and Alkaline Earth MetalsThe glycolates \documentclass{article}\pagestyle{empty}\begin{document}$$ \begin{array}{l} {\rm M}^{\rm I} [{\rm OCH}_{\rm 2} {\rm CH}_{\rm 2} {\rm OH}]{\rm with M}^{\rm I} = {\rm Li, Na, K} \\ \mathop {\rm M}\nolimits_{\rm 2}^{\rm I} [{\rm OCH}_{\rm 2} {\rm CH}_{\rm 2} {\rm O}]{\rm with M}^{\rm I} = {\rm Li, Na, K, Tl} \\ {\rm M}^{{\rm II}} [{\rm OCH}_{\rm 2} {\rm CH}_{\rm 2} {\rm O}]{\rm with M}^{{\rm II}} = {\rm Mg, Ca, Sr, Ba} \\ \end{array} $$\end{document} have been prepared and characterized by different methods. The IR spectra have been assigned.
    Notes: Nach verschiedenen Methoden wurden die Glykolate \documentclass{article}\pagestyle{empty}\begin{document}$$ \begin{array}{l} {\rm M}^{\rm I} [{\rm OCH}_{\rm 2} {\rm CH}_{\rm 2} {\rm OH}]{\rm mit M}^{\rm I} = {\rm Li, Na, K}\\ \mathop {\rm M}\nolimits_{\rm 2}^{\rm I} [{\rm OCH}_{\rm 2} {\rm CH}_{\rm 2} {\rm O}]{\rm mit M}^{\rm I} = {\rm Li, Na, K, Tl}\\ {\rm M}^{{\rm II}} [{\rm OCH}_{\rm 2} {\rm CH}_{\rm 2} {\rm O}]{\rm mit M}^{{\rm II}} = {\rm Mg, Ca, Sr, Ba} \end{array} $$\end{document} hergestellt und charakterisiert. Die IR-Spektren wurden zugeordnet.
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  • 42
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 407 (1974), S. 266-286 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Metallation of the PH2 Group in Silylphosphines1. The silylphosphines (CH3)2HSi—PH2, CH3H2Si—PH2, H3Si—PH2 react with LiP(C2H5)2 (molar ratio 1:2, in diglyme, at low temperature) yielding e.g. H3Si—PLi2 following eq. (1). These react with CH3Cl acc. to eq. (2).2. (CH3)nH3-nSi—PHLi compounds are readily obtained by reaction of PH2-containing silylphosphines with LiPHCH3 following eq. (3), since LiPHCH3 does not react to form dimetallated derivatives (low base-strength).3. Solutions of the monometallated silylphosphines in mono-, di-, or triglyme disproportionate according to eq. (4) either on warming to room temperature, or adding nonpolar solvents. The disproportionation reactions attain equilibria eq.(4).4. Etherates of the metallated disilylphosphines as e. g. [(CH3)3Si]2PLi · 1 monoglyme may be isolated on evaporating the solvent. In benzene solution these compounds react with CH3Cl to form disilymethylphosphines as shown in eq. (5). Halosilanes react to form trisilylphosphines acc. to (6).5. Reactions of AlCl3 with the monometallted monosilylphosphines [formed acc. to (3)] in diglyme follow eq. (7). Diglyme solutions of LiAl(PHSiH3)4 or LiAl(PHSiH2CH3)4 are stable at room temperature and react with CH3Cl or halosilanes to yield the corresponding P—H derivatives acc. to eq. (8). Compounds containing Al—P(SiH3)2- and Al—PH2- moieties, partially formed in the AlCl3 reaction because of eq. (4), react with halosilanes in a manner similar to eq. (8) yielding tri- and monosliylphosphines respectively. The latter compounds are also formed by partial disproportionation of the disilylphosphines. The nmr data of the compounds are reported.
    Notes: 1. Silylphosphine mit der PH2-Gruppe {(CH3)3SiPH2 (CH3)2 HSi—PH2, CH3H2Si—PH2, H3Si—PH2} bilden mit LiP(C2H5)2 (Molverhältnis 1:2) in Diglym bei niedriger Temperatur dimetallierte Silylphosphine; z. B. H3Si—PLi2 nach Diese reagieren mit CH3Cl nach 2. Die Verbindungen H3-x(CH3)xSi—PHLi werden präparativ durch Umsetzung der PH2-haltigen Silylphosphine mit LiPHCH3 nach Gl. (3) erhalten, da LiPHCH3 nie zu den dimetallierten Derivaten reagiert (geringe Basenstärke). 3. Die Lösungen der monometallierten Silylphosphine in Mono-, Di- oder Triglym disproportionieren beim Erwärmen auf Raumtemperatur und bei Zugabe von unpolaren Lösungsmitteln entsprechend Gl. (4) Diese Disproportionierungen führen zu Gleichgewichten.4. Beim Abdestillieren des Lösungsmittels können ätherate der metallierten Disilylphosphine wie z. B. [(CH3)3Si]2PLi · 1 Monoglym isoliert werden. Diese reagieren in Benzol mit CH3Cl zu den Disilylmethylphosphinen nach Gl. (5) Mit Halogensilanen werden Trisilylphosphine gebildet entsprechend Gl. (6) 5. Die monometallierten Monosilylphosphine reagieren mit AlCl3 in Diglym entsprechend Gl. (7); Die Lösungen von LiAl(PHSiH3)4 oder LiAl(PHSiH2CH3)4 in Diglym sind bei Raumtemperatur haltbar und reagieren mit CH3Cl oder Silylhalogeniden zu den entsprechenden PH-haltigen Verbindungen z. B. nach Gl. (8) Im Gemisch vorhandene Al—P(SiH3)2- und Al—PH2-Verbindungen aus Gl. (4) und AlCl3 geben in der zu Gl. (8) analogen Reaktion mit Halogensilanen Tri- bzw. Monosilylphosphine, in die die bereits gebildeten Disilylphosphine ebenfalls teilweise disproportionieren.Es werden die NMR-Spektren der Verbindungen angegeben.
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  • 43
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 407 (1974), S. 295-304 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Preparation of Silylphosphines of the X3-(n+m)(CH3)nHmSi—PH2 Type (X = F, Cl, Br)Reactions of halosilanes with silylphosphines containing PH2-groups are reported. CH3SiHCl—PH2 is obtained by (1) For the synthesis of Cl3Si—PH2 reactions of SiCl4 with CH3SiH(PH2)2, CH3SiH2—PH2 and (CH3)3Si—PH2 are carried out in a manner analogous to that shown in eq. (2) Side reactions are observed. Cl3Si—PH2 is isolated in mixture with SiCl4 and CH3SiHCl—PH2 when the most reactive of the above compounds, CH3SiH(PH2)2 is utilized.
    Notes: Es wird über Reaktionen zwischen Halogensilanen und PH2-haltigen Silylphosphinen berichtet. CH3SiHCl—PH2 wird nach Gl. (1) zugänglich. Zur Bildung von Cl3Si—PH2 wurden Umsetzungen von SiCl4 mit CH3SiH(PH2)2, CH3SiH2—PH2 und (CH3)3Si—PH2 durchgeführt, wobei Reaktionen entsprechend Gl. (2) eintreten. Es treten Nebenreaktionen auf. Beim reaktionsfähigeren CH3SiH(PH2)2 ist die Isolierung von Cl3Si—PH2 im Gemisch mit SiCl4 und CH3SiHCl—PH2 möglich. Unter den Reaktionsbedingungen (50°C) zerfällt Cl3Si—PH2 in PH3 und Si—P-Polymere. SiBr4 reagiert bereits bei Raumtemperatur. Durch Umsetzung mit CH3SiH(PH2)2 werden je nach Reaktionsdauer CH3SiHBr—PH2, Br3Si—PH2 und auch Br2Si(PH2)2 zugänglich. Auch die Reaktion mit CH3SiH2—PH2 führt zum Br3Si—PH2 neben CH3SiH2Br. Mit FSiBr3 bildet CH3SiH(PH2)2 das FSiBr2—PH2 neben CH3SiHBr—PH2, während bei den F-reicheren Derivaten F2SiBr2 und F3SiBr die Disproportionierung in SiF4 gegenüber der Si—P-Spaltung überwiegt. Es werden die NMR-Daten der Verbindungen angegeben.Cl3Si—PH2 decomposes into PH3 and Si—P-polymers under the reaction conditions (50°C). SiBr4 however will react at room temperature. Depending on the time of reaction CH3SiHBr—PH2, Br3Si—PH2 and even Br2Si(PH2)2 are obtained with CH3SiH(PH2)2. Also the reaction with CH3SiH2—PH2 leads to the formation of Br3Si—PH2 in addition to CH3SiH2Br. With FSiBr3, CH3SiH(PH2)2 forms FSiBr2—PH2 together with CH3SiHBr—PH2. In the reaction of the higher fluorinated derivatives F2SiBr2 and F3SiBr the disproportion into SiF4 is found to be preferred to Si—P cleavage and therefore these reactions can not be adequately used. The nmr data are reported.
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  • 44
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 408 (1974), S. 75-82 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: New Oxocobaltates(IV): Cs2[CoO3] Rb2[CoO3] and K2[CoO3]The hithertoo unknown compounds K2CoO3, Rb2CoO3 and Cs2CoO3 (all black) crystallize according to single crystal investigations orthorhombic (D2h18—Cmca; K2CoO3: a = 5.749, b = 11.303, c = 12.632 Å; Rb2CoO3: a = 5.871, b = 11.816, c = 13.193 Å; Cs2CoO3: a = 6.011, b = 12.519, c = 13.763 Å). From the determination of crystal structure of Cs2CoO3 results, that similar to Rb2TiO3 there are∞1[CoO3] chains with Co4+ tetrahedrally coordinated by oxygen.
    Notes: Neu dargestellt wurden K2CoO3, Rb2CoO3 und Cs2CoO3 (alle schwarz); diese kristallisieren nach Einkristalldaten orthorhombisch (D2h18—Cmca; K2CoO3: a = 5,749, b = 11,303, c = 12,632 Å; Rb2CoO3: a = 5,871, b = 11,816, c = 13,193 Å; Cs2CoO3: a = 6,011, b = 12,519, c = 13,763 Å). Die Strukturbestimmung an Cs2CoO3 zeigt, daß, wie bei Rb2TiO3, ∞1[CoO3]-Zweiereinfachketten vorliegen, Co4+ also tetraedrisch von Sauerstoff koordiniert ist.
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  • 45
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 403 (1974), S. 61-71 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: On Glass-Forming and Properties of Chalkogenide Systems. IV. Leadthiogermanate(II, IV) Glasses and their PropertiesPbS forms with GeS2 in the presence of GeS stable glasses in a large range of composition. Melts containing an excess of sulphur yield inhomogenious products. Substituting PbS for GeS, the values of the atomic volume of the glasses at first decrease. The glass transition points as well as the optical and electrical properties are noticed and the crystalline phases received on annealing are discussed with respect to the glass-forming region. The results give the fundamentals to consider the vitreous materials of the system PbS—GeS—GeS2 as leadthiogermanate(II, IV) glasses.
    Notes: PbS bildet mit GeS2 in Anwesenheit von GeS innerhalb weiter Grenzen stabile Gläser. Schmelzen mit überschüssigem Schwefel führen zu inhomogenen Produkten. Die schrittweise Substitution des GeS-Gehalts in den Gläsern durch PbS ist zunächst mit einer Abnahme des mittleren Atomvolumens verbunden. Die Transformationstemperaturen sowie die optischen und elektrischen Eigenschaften werden mitgeteilt und die bei der Rekristallisation entstehenden Phasen dem Glasbildungsbereich zugeordnet. Die Ergebnisse rechtfertigen, die im System PbS—GeS—GeS2 erhaltenen glasartigen Substanzen als Bleithiogermanat(II, IV)-Gläser zu betrachten.
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  • 46
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 403 (1974), S. 81-86 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: On Chalkogenolates. LXIV. Studies on Thioformic Acids. 7. Crystal Structure of Tetraethylammonium CyanidithioformateTetraethylammonium cyandithioformate [(C2H5)4N][NCCS2] crystallizes in the orthorhombic space group Pbem—D2h11 (no. 57): a = 7.715; b = 13.945; c = 12.255 Å and Z = 4.Planar cyandithioformate ions are packed parallel the xy plane at z = 0.25 and 0.75. The nitrogen atoms of the ammonium groups build columns along the glide plane c. Structural refinements were completed to a weighted R = 0.078.
    Notes: Tetraäthylammoniumcyandithioformiat [(C2H5)4N][NCCS2] kristallisiert rhombisch in der Raumgruppe Pbcm - D2h11 (Nr. 57): a = 7,715; b = 13,945; c = 12,255 Å und Z = 4.Die planaren Cyandithioformiationen sind parallel zur xy-Ebene in der Höhe z = 0,25 und 0,75 symmetrisch zur Gleitspiegelebene c angeordnet. Die Stickstoffatome der Ammoniumgruppen liegen auf der Gleitspiegelebene c in der Höhe z = 0 und 0,5, so daß eine säulenförmige Anordnung der Ammoniumionen parallel zur c-Achse resultiert. Die Struktur wurde bis auf einen R-Wert von 0,078 verfeinert.
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  • 47
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 403 (1974), S. 72-80 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Effect of Alkali Contamination on the Catalytic Properties of Al2O3—Si2Catalytic properties of amorphous Al2O3—SiO2 catalysts containing different amounts of Al2O3 in dehydration of isopropanol and cracking of cumene were examined after a defined contamination of the acid centers by sodium ethylate from alcoholic solution. In both reactions, the catalytic activity is decreased by treatment with sodium ethylate, the cracking of cumene being suppressed at a lower alkali concentration than the dehydration of isopropanol. In dehydration of isopropanol, the dependence of the catalytic activity on the alkali content is influenced strongly by the Al2O3 content of the catalysts. In the cracking of cumene, strongly acid Brönsted centers are active, whereas the dehydration of isopropanol proceeds by joint action of acid Lewis or Brönsted centers, respectively, with basic centers at the surface of the catalyst (hydroxide groups or oxygen anions).
    Notes: An amorphen Al2O3—SiO2-Katalysatoren unterschiedlichen Al2O3-Gehaltes wurden nach definierter Vergiftung der sauren Zentren mit Natriumäthylat aus alkoholischer Lösung die katalytischen Eigenschaften bei der Isopropanoldehydratisierung und bei der Cumolspaltung untersucht. Die Natriumbehandlung vermindert für beide Reaktionen die katalytische Aktivität, wobei die Cumolspaltung bereits bei niedrigeren Alkalikonzentrationen unterdrückt wird als die Isopropanoldehydratisierung. Der Charakter der Abhängigkeit der katalytischen Aktivität bei der Isopropanoldehydratisierung vom Alkaligehalt wird stark vom Al2O3-Gehalt der Katalysatoren beeinflußt. Für die Cumolspaltung sind stark saure BRÖNSTED-Zentren aktiv, während die Isopropanoldehydratisierung unter gemeinsamer Beteiligung von sauren Lewis- bzw. BrÖnsted-Zentren mit basischen Zentren der Katalysatoroberfläche (Hydroxidgruppen oder Sauerstoffionen) abläuft.
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  • 48
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 403 (1974), S. 97-106 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The EMF of cells with transference of the type Cl2, C/MeCl ⋮ SrCl2—MeCl(x)/C, Cl2 is measured in the molten mixtures SrCl2—MeCl (Me = Li, Na, K, Rb, Cs).From the EMF-values and values of aktivities from another independent methods the transference numbers of the cations Sr2+ and Me+ relative to the chloride ion in the molten mixtures SrCl2—LiCl, SrCl2—NaCl and SrCl2—KCl are calculated. The values of aktivities for the systems SrCl2—LiCl and SrCl2—NaCl are calculated from cryoscopic analysis of the eutectic phase diagrams.
    Notes: In Mischungen SrCl2—MeCl (Me = Li, Na, K, Rb, Cs) wurden die EMK von Zellen mit Überführung vom Typ Cl2, C/MeCl ⋮ SrCl2—MeCl (x)/C, Cl2 bestimmt. Die Zellen-EMK und die aus unabhängigen Methoden ermittelten Aktivitätsdaten ermöglichen, die Überführungszahlen der Kationen Sr2+ und Me+ in den geschmolzenen Mischungen SrCl2—LiCl; SrCl2—NaCl und SrCl2—KCl in bezug auf das Chloridion zu berechnen.Für die Systeme SrCl2—LiCl und SrCl2—NaCl werden die Aktivitätsdaten aus den Schmelzdiagrammen ermittelt.
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  • 49
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 403 (1974), S. 127-136 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: On Hexafluorotitantes (III). Cs2MTIF4 and Rb2MTIF4(M=K, Na); with a Remark on TI3TIF6By heating the binary fluorides in a closed system we obtained Cs2KTiF6 (a = 9.124 Å), Rb2KTiF6 (a = 8.932 Å) and Rb2NaTiF6 (a = 8.533 Å), all cubic Elpasolithes of light blue colour as well as Cs2NaTiF6 (hexagonal a = 6.272, c = 30.91 Å, isotypic with Cs2NaCrF6) and Tl3TiF6TiF3 (3.1-295.5°K) and Cs2KTiF6 (74.9-297.7°K) have been measured magnetically. The spectra of reflection in the range of 10 000 to 30 000 cm-1 of TiF3 and the new quaternary fluorides are similar. The Madelung Part of Lattice Energy (MAPLE) is calculated and discussed.
    Notes: Durch Erhitzen der binären Fluoride im geschlossenen System erhielten wir Cs2KTiF6 (a = 9,124 Å), Rb2KTiF6 (a = 8,932 Å) und Rb2NaTiF6 (a = 8,533 Å), alles kubische, hellblaue Elpasolithe, sowie hexagonales Cs2NaTiF6 (a = 6,272, c = 30,91 Å, isotyp mit Cs2NaCrF6) und kubisches Tl3TiF6.TiF3 (3,1 bis 295,5°K) und Cs2KTiF6 (74,9 bis 297,7°K) wurden magnetisch vermessen. Die Reflexionsspektren im Bereich 10 000 to 300 000 cm-1 von TiF3 und den neuen quaternären Fluoriden entsprechen einander weitgehend. Der Madelunganteil der Gitterenergie, MAPLE, wird berechnet und diskutiert.
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  • 50
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 403 (1974), S. 137-142 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Studies on Selenium Compounds. LXVIII. Infrared Spectra of (CH2NH2)SeO and (CH3NH)2SeOThe infrared spectra of the compounds (CH2NH)2SeO and (CH3NH)2SeO are presented and assigned by comparison with analogous compounds. The bond relations in both amides are discussed. Strong intermolecular hydrogen-bonds are formed between the Se =O and NH bond.
    Notes: Die Infrarotspektren der Verbindungen (CH2NH)2SeO und (CH3NH)2SeO werden mitgeteilt und über den Vergleich mit analogen Verbindungen zugeordnet. An Hand der IR-Spektren werden die Bindungsverhältnisse beider Verbindungen diskutiert. Die SeO-Bindung bildet mit der NH-Bindung starke intermolekulare Wasserstoffbrückenbindungen.
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  • 51
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: On Perovskite Phases in the Systems AO—SE2O3—UO2,x with A=Alkaline Earth Metal and SE = Rare Earths, La and Y. VI. I.R. spectroscopical Investigations at the Compounds Ba2SE0,67UO6 and Ba2SE0,67UO5,5According to the results of the i.r. spectroscopic investigations longer and shorter U—O-distances can be distinguished. The HT- and LT-modifications of Ba2SE0,67UO6 contain UO22+-groups like other ternary uranium oxides. In the O-modifications these groups are only incompletely formed. On the contrary the perovskites Ba2SE0,67UO5,5 with U(V) show two different longer U—O-bonds only.
    Notes: Die IR-spektroskopischen Untersuchungen erlauben, zwischen längeren und kürzeren U—O-Abständen zu unterscheiden. Die HT- und TT-Modifikationen von Ba2SE0,67UO6 enthalten UO22+-Gruppen wie andere ternäre Uranoxide. In den O-Modifikationen sind diese Gruppierungen nur unvollständig ausgebildet. Die U(V)-haltigen Perowskite Ba2SE0,67UO5,5 weisen dagegen nur zwei verschiedene längere U—O-Abstände auf.
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  • 52
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    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 408 (1974), S. 151-166 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The First Oxoferrate(III) with a Discrete Anion: K6[Fe2O6]Heating of intimate mixtures of KO0.56 and “FeO” (K:Fe = 2.2:1) in a closed iron-tube at 600°C leads to red monoclinic single crystals with a = 7.133 b = 11.155 c = 6.510 Å β = 102.0° shown to have the composition K6[Fe2O6] (R = R′ = 5.5%) by three dimensional structural analysis employing direct methods [706 hk0—hk8 diffractometer data, Mo—Kα]. Space group C2/m—C2h3 (parameters see text). Surprisingly the compound is the first oxoferrate(III) with a discrete anion. This nearly has the shape of two tetrahedras sharing a common edge. The Madelung Part of Lattice Energy (MAPLE) is calculated and discussed.
    Notes: Durch Erhitzen inniger Gemenge von KO0,56 und „FeO“ (K:Fe = 2,2:1) im geschlossenen Eisen-Bömbchen bei 600°C erhielten wir rote monokline Einkristalle, a = 7,132 b = 11,155 c = 6,510 Å β = 102,0°, denen nach der dreidimensionalen Strukturaufklärung mittels direkter Methoden [706 hk0—hk8 Diffraktometer-Daten (Mo—Kα)] die Zusammensetzung K6[Fe2O6] [R = R′ = 5,5%] zukommt. Die Raumgruppe ist C2/m-C2h3; Parameter siehe Text.überraschend liegt hier das erste Oxoferrat(III) mit isoliertem Anion vor. Dieses hat annähernd die Gestalt zweier durch eine gemeinsame Kante verknüpfter Tetraeder. Der Madelung-Anteil der Gitterenergie (MAPLE) wird berechnet und diskutiert.
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  • 53
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    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 408 (1974), S. 180-186 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Coordination Chemistry of Rhenium(VII). V. Trioxotrichlororhenates(VII) with Nitrogen-containing CationsComplex compounds of the composition A2ReO3C3 were obtained by reaction of ReO3Cl with the chlorides ACl (A = (CH3)4N+, (C2H5)4N+, PyH+, ChinH+ (CH3)3NH+ and CH3Py+) in inert solvents. It has been decuced from the Re—O stretching vibrations of the IR spectra, that the anion ReO3Cl32- in connection with the cations (CH3)4N+ resp. (C2H5)4N+ has the symmetry C3v (cis-configuration). It is probable, that in cations including a NH-group a decrease of the symmetry towards Cs arises by means of the hydrogen bondings.
    Notes: Durch Umsetzung von ReO3Cl mit den Chloriden ACl (A —(CH3)4N+, (C2H5)4N+, PyH+, ChinH+, (CH3)3NH+ und CH3Py+) in inerten Lösungsmitteln werden Komplexe der Zusammensetzung A2ReO3Cl3 erhalten. Aus den Re—O-Valenzschwingungen der IR-Spektren ergibt sich, daß das ReO3Cl32--Anion in seinen Salzen mit (CH3)4N+ und (C2H5)4N+ C3v-Symmetrie (cis-Konfiguration) aufweist. Bei Kationen, die eine NH-Gruppe enthalten, tritt wahrscheinlich infolge von Wasserstoffbrückenbindungen Symmetrieerniedrigung nach Cs ein.
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  • 54
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 408 (1974), S. 209-213 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Preparation and Crystal Structure of Rubidium Triiodoplumbate(II)RbPbJ3 crystallizes in the orthorhombic space group Pnam(D2h16) (lattice parameters see above); it is isomorphous with CsPbJ3. The crystal structure has been determined from 1452 independent reflexes by Patterson- and Fourier-syntheses and refined three dimensionally by least-squares-methods.6 I surround Pb nearly octahedrally. The octahedra are arranged in the form of double chains along the c-axis, which are held together by Rb. (Pb—I bond distances see above). The “inert 6s-pair” at Pb is stereochemically inactive.
    Notes: RbPbJ3 kristallisiert orthorhombisch in der Raumgruppe Pnam (D2h16) mit a = 10,274(1), b = 17,381(2), c = 4,773(1) Å und Z = 4; es ist isomorph mit CsPbJ3. Die Kristallstruktur wurde anhand von 1452 unabhängigen Reflexen mittels Patterson- und Fourier-Synthesen bestimmt und nach der Kleinste-Quadrate-Methode dreidimensional verfeinert.Pb ist nahezu oktaedrisch von 6 J umgeben. Die Oktaeder bilden längs der c-Achse Doppelketten, die von Rb zusammengehalten werden. Die Pb-J-Bindungsabstände betragen 3,037(2), 3,382(2), 3,224(1), 3,253(1) Å. Das „inerte 6s-Elektronenpaar“ des Pb tritt sterisch nicht in Erscheinung.
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  • 55
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 408 (1974) 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 56
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    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 408 (1974), S. 187-204 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: High and Low Spin Behaviour of Ni3+-Ions in Octahedral CoordinationThe compounds Cs2NaNiF6, Cs2KNiF6, Rb2KNiF6, K3NiF6, and Na3NiF6 were investigated by ligand field and EPR spectroscopy between 298 and 4,2 K. These fluorides — with the exception of the first one - crystallise in the cubic elpasolite lattice or in distorted modifications of this structure type and contain the Ni3+ ions in the low spin configuration t2g6eg1. This configuration is stabilised versus the high spin alternative t2g5eg2 by an appreciable Jahn-Teller splitting of the 2Eg-state of about 7000 cm-1. The NiF6-octahedra are tetragonally elongated, the distortion being dynamical at 298 K. In case of the cubic compound Rb2KNiF6 a transition to a tetragonal structure with c/a 〉 1 as a consequence of a ferrodistortive Jahn-Teller ordering is observed at lower temperatures. It is calculated from the anisotropic g-parameters, that the first excited quartet level 4A2g(4T1g — t2g5eg2) has an energy which is about 1000 cm-1 higher than that of the 2A1g(2Eg — t2g6eg1) groundstate. Spin-orbit interactions between the energetically neighboured 2A1g(2Eg) and 4A2g, 4Eg(4T1g) states lead to third order contributions to the g-factors, which are very sensitive with respect to the doublet-quartet separation. In the hexagonal compound Cs2NaNiF6 finally, in which half of the Ni3+ ions occupy octahedral sites connected by common corners as in the other fluorides, while the other half is located in octahedral sites with common faces, high and low spin Ni3+ ions are found side by side. Obviously the latter half of these Ni3+ ions is geometrically restricted with respect to a Jahn-Teller distortion and hence the high spin configuration energetically favoured.
    Notes: Die Ni3+-Ionen enthaltenden Verbindungen Cs2NaNiF6, Cs2KNiF6 Rb2KNiF6, K3NiF6 und Na3NiF6 wurden ESR- und ligandenfeldspektroskopisch im Temparaturbereich zwischen 298° und 4,2°K untersucht. Die vier letztgenannten Fluoride, die im kubischen Elpasolithgitter oder verzerrten Varianten dieser Struktur kristallisieren, enthalten die Ni3+-Ionen im Low-Spin-Zustand. Er wird durch die Jahn-Teller-Instabilität der Konfiguration t2g6eg1, die zu einer tetragonalen Weitung der NiF6-Oktaeder und zu einer Aufspaltung des 2Eg-Zustandes von ca. 7000 cm-1 führt, stabilisiert. In übereinstimmung damit verzerrt sich das bei Raumtemperatur kubische Rb2KNiF6 beim Abkühlen tetragonal mit c/a 〉 1. Aus den gemessenen anisotropen g-Faktoren errechnet sich, daß der erste angeregte Quartett-Term 4A2g(4T1g — t2g5eg2) etwa 1000 cm-1 über dem 2A1g(2Eg — t2g6eg1)-Grundzustand liegt. Die LS-Kopplung hat zu Wechselwirkungen zwischen den eng benachbarten 2A1g(2Eg)- und 4A2g, 4Eg(4T1g)-Termen geführt, die numerisch erhebliche Beiträge zu den g-Parametern liefern und die energetische Dublett-Quartett-Separation sehr empfindlich widerspiegeln. Im hexagonalen Cs2NaNiF6 schließlich, in dem die dreiwertigen Kationen je zur Hälfte über gemeinsame Ecken verbundene und flächenverknüpfte Oktaeder besetzen, wurden nebeneinander Ni3+-Ionen im Low-Spin- und im High-Spin-Zustand gefunden. Es konnte wahrscheinlich gemacht werden, daß für die durch Flächenverknüpfung in ihren geometrischen Möglichkeiten zu einer Verzerrung eingeschränkten NiF6-Polyeder die elektronische Jahn-Teller-Aufspaltung zur Stabilisierung des Low-Spin-Zustandes nicht mehr ausreicht.
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  • 57
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    Zeitschrift für anorganische Chemie 408 (1974), S. 255-260 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: IR Spectra and Forcefields of Ternary Alkali-Yttrium Fluorides with Elpasolite StructureIR spectra of A2BYF6 are reported and five force constants are calculated using a modified valence force field. The results are discussed with respect to the two bond characters.
    Notes: Es werden die IR-Spektren von A2BYF6 (A = K, Rb, Cs; B = Na, K, Rb, Cs) mitgeteilt und daraus mittels eines modifizierten Valenzkraftfeldes fünf Kraftkonstanten berechnet. Die Ergebnisse werden für die beiden Bindungsarten diskutiert.
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  • 58
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Contributions to the Chemistry of Phosphorus. 53. 1,2,3,4-Tetraphenylcyclo-5-thia-1,2,3,4-tetraphosphane1,2,3,4-Tetraphenyl-cyclo-5-thia-1,2,3,4-tetraphosphane (“tetraphenylcyclotetraphosphine-monosulphide„) 1 is obtained in very good yield and purity by the reaction of pentaphenyl-cyclopentaphosphane (2) with sulphur (4 C6H5P: 1 S). Further new methods of preparation are the comproportionation of 2 with (C6H5PS)3, and the reaction of dipotassium-triphenyl-cyclotriphosphide (4) with sulphur dichloride. The IR and 31P-NMR spectra of the title compound indicate unambiguously the heterocyclophosphane structure 1 with a five-membered P4S ring. The elevated stability of this ring system is evident from numerous other formation reactions, which are reported in addition.
    Notes: 1,2,3,4-Tetraphenyl-cyclo-5-thia-1,2,3,4-tetraphoshan (“Tetraphenyl-cyclotetraphosphin-monosulfid”) 1 wird durch Umsetzung von Pentaphenyl-cyclopentaphosphan (2) mit Schwefel (4 C6H5P:1 S) in sehr guter Ausbeute und Reinheit erhalten. Weitere neue Darstellungswege sind die Komproportionierung von 2 und (C6H5PS)3 sowie die Reaktion von Dikalium-triphenyl-cyclotriphosphid (4) mit Schwefeldichlorid. Das IR- und das 31P-NMR-Spektrum der Verbindung sind ein eindeutiges Indiz für die Heterocyclophosphan-Struktur 1 mit fünfgliedrigem P4S-Ring. Die besondere Stabilität dieses Molekelgerüstes geht aus der größeren Zahl weiterer Bildungs-Reaktionen für 1 hervor, über die außerdem berichtet wird.
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  • 59
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    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 403 (1974) 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 60
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    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 403 (1974), S. 35-40 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Mixed Dicyanamido (thio) cyanato-cobaltates(II)Preparation and properties of mixed anionic pseudohalide-complexes of cobalt(II) [CoX2Y2]2- and [CoX3Y]2- (X = NCS, NCO, Y = N(CN)2) are reported. The structures of the complexes are discussed using the results of infrared and electronic spectroscopy and of magnetic measurements.
    Notes: Es wird über Darstellung und Eigenschaften gemischter Pseudohalogeno-kobaltate(II) [CoX2Y2]2- und [CoX3Y]2- (X = NCO, NCS; Y = N(CN)2) berichtet. Die Struktur der Komplexe wird unter Heranziehung von Elektronen- und Infrarotspektren sowie von magnetischen Messungen diskutiert.
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  • 61
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    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 403 (1974), S. 1-22 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Some Aspects of the Structural Chemistry of the Rare Earth TrifluoridesThe preparation and characterization of the rare earth trifluorides crystallizing in the hexagonal LaF3-type and the orthorhombic YF3-type is described. The lattice parameters were derived from GUINIER powder data of high precision. These lattice parameters served to calculate the effective ionic radii of the tripositive rare earth ions for coordination numbers 8 and 9. It is shown that both structure types can be stabiblized by the formation of nonstoichiometric compounds of the general formula (Me, RE)Fx (Me ≙ Eu2+, Sr2+ and RE ≙ Eu3+, Gd3+) with x varying approximately from 2,77 to 2,94 for the hexagonal and from 2,94 to 3,00 for the orthorhombic nonstoichiometric phases. For the pure trifluorides and the nonstoichiometric phases a critical radius ratio of 0.830±0.008 was found for the changeover from the LaF3- to the YF3-structure.
    Notes: Es wird die Präparation und Charakterisierung der im LaF3- und YF3-Typ kristallisierenden Selten-Erd-Trifluoride beschrieben. Die Gitterparameter wurden nach der GUINIER-Methode mit hoher Präzision bestimmt und daraus für SE3+- Ionen mit der Koordinationszahl 8 und 9 effektive Ionenradien abgeleitet. Es wird gezeigt, daß sich beide Strukturtypen in nichtstöchiometrischen Verbindungen der allgemeinen Formel (Me, SE)Fx (Me ≙ Eu2+, Sr2+ und SE ≙ Eu3+, Gd3+) stabilisieren lassen mit Phasenbereichen von x = 2,77 bis x = 2,94 für die hexagonalen und von x = 2,94 bis x = 3,00 für die orthorhombischen festen Lösungen. Für die stöchiometrischen und nichtstöchiometrischen Fluoride wurde der Grenzradienquotient zwischen LaF3- und YF3-Struktur zu 0,830 ± 0,008 ermittelt.
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  • 62
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    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 403 (1974), S. 41-44 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Anionie Nickel Pseudohalide Complexes of the Types [Ni{N(CN)2}3]- and [Ni{N(CN)2}2(NCS)2]2-The preparation of a new type of anionic pseudohalide complexes of nickel [Ni{N(CN)2}3]- and of mixed thiocyanate-dicyanamide complexes [Ni{N(CN)2}2(NCS)2]2- is reported. The structures of the complexes are discussed on the basis of IR- and magnetic measurements. The new compounds are representing polymer octahedral complexes with a bridging function of the dicyanamide ligands.
    Notes: Es wird über die Darstellung eines neuen Typs anionischer Nickelpseudohalogenid-Komplexe [Ni{N(CN)2}3]- sowie gemischter Thiocyanat-Dicyanamid-Komplexe [Ni{N(CN)2}2(NCS)2]2- berichtet. Die Struktur der Komplexe wird auf der Grundlage von IR-spektroskopischen Untersuchungen sowie von magnetischen Messungen diskutiert. Die Verbindungen repräsentieren polymer oktaedrische, durch Dicyanamid-Gruppen verbrückte Komplexe.
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  • 63
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Crystallorgraphic Studies on Rare-Earth Dihalides. The Crystal Structure of Ytterbium (II) -chloride, YbCl2Using 452 reflexions collected on an automatic two-circle diffractometer with MoKα radiation the structure of YbCl2 was refined to a residual R = 0.025. The structural parameters of YbCl2 are in good agreement with those of SrI2. This is to be expected if the radius ratio is accepted as the main structural principle. The geometrical details of the coordination polyhedra around the sevenfold coordinated Yb2+ ion and the three- and fourfold coordinated Cl- ions are discussed in short. It is shown that the calculated vibrational parameters are physically relevant.
    Notes: Für Ytterbium(II)-chlorid wurde mit Hilfe von 452 Einkristallinterferenzen, die auf einem automatischen Zweikreisdiffraktometer mit MoKα-Strahlung gemessen wurden, eine Strukturverfeinerung bis zu einem Zuverlässigkeitsindex R = 0,025 durchgeführt. Die strukturellen Parameter von YbCl2 stimmen weitgehend mit denjenigen von SrJ2 überein. Dieser Befund ist plausibel, wenn man den Ionenradienquotienten als Strukturargument gelten läßt. In einer kurzen Diskussion werden kristallchemische Details der Koordinationspolyeder des siebenfach koordinierten Yb2+-Ions und der drei- bzw. vierfach koordinierten Cl--Ionen besprochen. Ferner wird gezeigt, daß die eingeführten anisotropen Temperaturfaktoren physikalisch relevant sind.
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  • 64
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    Zeitschrift für anorganische Chemie 403 (1974), S. 95-96 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 65
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    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 403 (1974) 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 66
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    Zeitschrift für anorganische Chemie 403 (1974), S. 87-94 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Massenspektren von Trisdithiocarbamaten. Massenspektroskopische Untersuchung von Trisdithiocarbamat-Komplexen des Arsens, Antomons und WismutsZehn Trisdithiocarbamat-Verbindungen von Arsen, Antimon und Wismut wurden massenspektrometrisch untersucht. Ihre Fragmentationsweise und die Fragment-Ionen mit gleichen Strukturen werden diskutiert. Die Peaks der Molekül-Ionen wurden von allen Verbindungen nicht beobachtet. Die Fragment-Ionen mit der größten Massen-Zahl, die direkt aus den Molekül-Ionen hervorgehen, sind diejenigen mit einer um eine Dithiocarbamat-Gruppe kleineren Masseneinheit, was eine leichte Abspaltung einer Dithiocarbamat-Gruppe andeutet. Die beobachteten Peaks sind auf Elektronenstoß oder auf pyrolytische Zersetzung zurückzuführen. Die stärksten Peaks im oberen Massenzahl-Bereich aller Spektren entsprachen Polynuklear-Verbindungen der allgemeinen Formel MnSm, wobei M = As, Sb, Bi; S = Schwefel; n = 1, 2, 3, 4 und m = 0, 1, 2, 3, 4, 5 sind.
    Notes: Ten trisdithiocarbamate compounds of arsenic, antimony and bismuth are studied by mass spectrometry. Their fragmentation modes and the fragment ions with common structures are discussed. The molecular ion peaks were not observed in all compounds. The highest mass number fragment ions, which might be generated directly from the molecular ions, are those with less mass units, equal to a dithiocarbamate group; signifing a facile detaching of one of the dithiocarbamato groups. The observed peaks are attributed, either to electron impact or to pyrolytic decomposition. The most prominent peaks, in the higher mass number region of all the spectra, correspond to polynuclear compounds of the general formula MnSm, where M = As, Sb, Bi; S = sulfur; n = 1, 2, 3, 4 and m = 0, 1, 2, 3, 4, 5.
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  • 67
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    Zeitschrift für anorganische Chemie 404 (1974), S. 87-96 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Oktaedrische Kobalt(III)-Komplexe vom Chloropentammin-Typ. XXXII. Cis-[Coen2(n-CxH2x+1NH2)Cl]2+- Komplexe mit langen Paraffin-KettenSalze von cis-[Coen2(n-CxH2x+1NH2)Cl]2+-Kationen (x = 4 bis 12) wurden dargestellt und ihre VIS- und IR-Spektren aufgenommen. Die Geschwindigkeits-konstanten der Solvolyse wurden bestimmt und die Aktivierungsparameter berechnet. Die spektralen und kinetischen Daten werden kurz diskutiert.
    Notes: Salts of the cis-[Coen2(n-CxH2x+1NH2)Cl]2+ cations where x = 4-12 have been prepared, and their visible and infrared spectra measured. Rate constants for their solvolysis have been determined over a range of temperatures and activation parameters calculated. These spectral and kinetic data are briefly discussed.
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  • 68
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    Zeitschrift für anorganische Chemie 403 (1974), S. 116-126 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Evidence and Applications of Gaseous Complexes during the Chemical TransportBy means of the chemical transport method the formation of gaseous complex compounds has been observed. Using Al2Cl6 as a transport agent, the chlorides FeCl2, CoCl2, NiCl2, CuCl2, PdCl2, PtCl2, MoCl3, YCl3, LaCl3, ThCl4 and UCl4 are transported within a temperature gradient. Similary are transported by means of Ga2Cl6 the chlorides CoCl2 and NiCl2, by means of Fe2Cl6 the chlorides FeCl2, CuCl2 and YCl3, by means of NbCl5 the chlorides NaCl and CrCl3.Examples concerning the practical application of gaseous complexes are refered.
    Notes: Mit der chemischen Transportmethode wird die Bildung von Gaskomplexen beobachtet. Mit Al2Cl6 als Transportmittel werden FeCl2, CoCl2, NiCl2, CuCl2, PdCl2, PtCl2, MoCl3, YCl3, LaCl3, ThCl4 und UCl4 im Temperaturgefälle transportiert. Analog werden transportiert mit Ga2Cl6 die Chloride CoCl2 und NiCl2, mit Fe2Cl6 die Chloride FeCl2, CuCl2, YCl3 und mit NbCl5 die Chloride NaCl und CrCl3.Beispiele für die praktische Anwendung von Gaskomplexen werden zusammengestellt.
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  • 69
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    Zeitschrift für anorganische Chemie 403 (1974), S. 143-148 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: On the RbNiCrF6 Type(1): On CsCuMF6 (M=NiIII, TiIII), CsMgMF6 (M =Co, Fe, Ga), and CsZnMF6 (M=NiIII, CoIII, FeIII)New prepared are the cubic compounds CsCuNiIIIF6 (dark brown, a = 10.14 Å); CsZnNiIIIF6 (dark brown, a = 10.17 Å); CsCuTiIIIF6 (light grey, a = 10.39 Å); CsMgGaF6 (colourless, a = 10.23 Å); CsMgFeF6 (colourless, a = 10.53 Å); CsZnFeF6 (colourless, a = 10.42 Å); CsMgCoIIIF5 (light blue, a = 10.27 Å) and CsZnCoIIIF6 (light blue, a = 10.34 Å), all RbNiCrF6-type of structure.The Madelung part of lattice energy, MAPLE, is calculated and discussed.
    Notes: Neu dargestellt wurden die kubischen Verbindungen CsCuNiIIIF6 (dunkelbraun, a = 10,14 Å); CsZnNiIIIF6 (dunkelbraun, a = 10,17 Å); CsCuTiIIIF6 (hellgrau, a = 10,39 Å); CsMgGaF6 (farblos, a = 10,23 Å); CsMgFeF6 (farblos, a = 10,35 Å) CsZnFeF6 (farblos, a = 10,42 Å); CsMgCoIIIF6 (hellblau, a = 10,27 Å) und CsZnCoIIIF6 (hellblau, a = 10,34 Å), alle RbNiCrF6-Typ. Der Madelunganteil der Gitterenergie, MAPLE, wird berechnet und diskutiert.
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  • 70
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    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 403 (1974), S. 163-172 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: On the Structural Chemistry of BaMg2X2 (X = Si, Ge, sn, Pb)The new compounds BaMg2X2 (X = Si, Ge, Sn, Pb) have been prepared and their structures have been determined. BaMg2Si2 and BaMg2Ge2 crystallize in the ThCr2Si2-type, BaMg2Sn2 and BaMg2Pb2 show two new atomic arrangements, which are layer variants of the former type.
    Notes: Die Verbindungen BaMg2X2 (X = Si, Ge, Sn, Pb) wurden dargestellt und strukturell untersucht. BaMg2Si2 und BaMg2Ge2 kristallisieren im ThCr2Si2-Typ während BaMg2Sn2 und BaMg2Pb2 jeweils neue Strukturtypen ausbilden. Diese lassen sich aber als Schichtvarianten an den ThCr2Si2-Typ anschließen.
    Additional Material: 6 Ill.
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  • 71
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    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 403 (1974), S. 156-162 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: On the Mechanism of the Formations of Chromium(IV)oxide from Chromyl ChlorideThe decomposition of chromyl chloride in the temperature range from 380 to 400°C leads with increasing oxygen pressure to chromium oxides containing up to nearly 90% of CrO2. The interaction with the chlorine prevents a quantitative formation of CrO2. Up to 315°C during the decomposition of chromyl chloride chromium oxides of higher valencies are formed separating chlorine and taking up oxygen simultaneously. By working in flowing oxygen it could be proved that the decomposition goes at lower temperatures via the nondetectable CrO3. By heating gradually and by removing the chlorine as far as possible stoichiometric CrO2 at oxygen pressures above 60 atm could be obtained.
    Notes: Die Chromylchloridzersetzung im Temperaturbereich von 380 bis 100°C führt unter steigendem Sauerstoffdruck zu Chromoxiden, die bis etwa 90% an CrO2 enthalten. Die Wechselwirkung mit Chlor verhindert dabei eine quantitative CrO2-Bildung. Beim Zerfall von Chromylchlorid im Sauerstoff entstehen bis 315°C unter Abspaltung von Chlor und gleichzeitiger Sauerstoffaufnahme höhere Chromoxide. Die Vermutung, daß die Zersetzung bei niedrigeren Temperaturen über das nichterfaßbare CrO3 abläuft, konnte im strömenden Sauerstoff bewiesen werden. Durch stufenweises Erhitzen und unter möglichst vollständiger Entfernung von Chlor konnte bei einem Sauerstoffdruck von über 60 atm reines CrO2 erhalten werden.
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  • 72
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    Zeitschrift für anorganische Chemie 403 (1974), S. 186-192 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Contributions to the Chemistry of Silicon-Sulphur Compounds. XVII. Preparation of Trialkoxysilanols from TrialkoxysilanethiolsThe hydrolysis of trialkoxysilanethiols in neutral, basic and acidic solutions was investigated and an efficient way for preparation of trialkoxysilanols was elaborated. Some trialkoxysilanols were obtained with a very good yield.
    Notes: Die Hydrolyse von Trialkoxysilanthiolen in neutralen, alkalischen und sauren Lösungen wurde untersucht und ein ergiebiger Weg zur präparativen Darstellung von Trialkoxysilanolen ausgewertet. Einige Trialkoxysilanole wurden mit sehr guter Ausbeute erhalten.
    Additional Material: 5 Ill.
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  • 73
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    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 404 (1974), S. 167-174 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Ligand Field Reflectance Spectroscopy at Low TemperaturesA spectrometer with a variable temperature attachment is described, which allows to register reflectance spectra between 300 and 4 K. The 298 K and low temperature spectra of some compounds with Ni2+- and Cr3+-ions in octahedral coordination are discussed.
    Notes: Es wird eine Meßvorrichtung beschrieben, die es ermöglicht, Remissionsspektren im Temperaturbereich zwischen 300 und 4 K zu registrieren. Die Raum- und Tieftemperaturspektren einiger Verbindungen mit Ni2+- und Cr3+-Ionen in oktaedrischer Koordination werden diskutiert.
    Additional Material: 8 Ill.
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  • 74
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    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 410 (1974), S. 219-224 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Über einige ternäre Legierungen der Seltenen Erden mit Fe2P-StrukturenDie Verbindungen SEInRh und SEInPt (mit verschiedenen Seltenen Erden) wurden dargestellt und metallographisch, röntgenographisch und durch Dichtemessungen untersucht. Sie besitzen eine hexagonale Fe2P-Struktur. Die charakteristischen Eigenschaften dieser Verbindungen werden mit denen aller anderen, früher untersuchten isostrukturellen Verbindungen der Seltenen Erden verglichen.
    Notes: The LnInRh and LnInPt compounds of various rare earths have been prepared and studied by metallographic, X-ray examination and density determination. Their structure resulted to be hexagonal Fe2P-type. The characteristics of these compounds have been compared with those of all the other isostructural compounds of the rare earths previously studied.
    Additional Material: 6 Ill.
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  • 75
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    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 410 (1974), S. 251-268 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The Stability of Gaseous Dimeric Chloride MoleculesUsing the high sensitivity of a mass spectrometer an increasing number of chlorides (halides) can be shown to form dimers. The qualitative observation of dimers was possible with AsCl3, TiCl4, GeCl4, SnCl4, and TeCl4. In addition the enthalpy of dimerization ΔH°(dim.) of the gaseous molecules BeCl2, CaCl2, SrCl2, BaCl2, ZnCl2, CdCl2, HgCl2, PbCl2, NiCl2, GaCl3, SbCl3, BiCl3, ScCl3, YCl3, ZrCl4, and HfCl4 has been determined by mass spectroscopic measurements (Table 1).A discussion of these data in combination with similar data taken from the literature is given. If Tb marks the boiling temperature of a chloride (in °K and referred to the monomeric molecules at 1 atm) then the relation Q = -ΔH°(dim., Tb)/Tb ≈ 23 cal/°, mole is valid. Larger Q-values are observed with the trichlorides AlCl3, GaCl3, InCl3, FeCl3, TiCl3 and ScCl3, which must be seen in connection with their structure in the condensed state.
    Notes: Bei entsprechender Empfindlichkeit der massenspektrometrischen Messung können bei zahlreichen Chloriden (Halogeniden dimere Gasmolekeln beobachtet werden. Die qualitative Beobachtung solcher Dimerer gelang mit AsCl3, TiCl4, GeCl4, SnCl4 und TeCl4. Darüber hinaus wurde die Dimerisierungsenthalpie ΔH°(dim.) der Gasmolekeln BeCl2, CaCl2, SrCl2, BaCl2, ZnCl2, CdCl2, HgCl2, PbCl2, NiCl2, GaCl3, SbCl3, BiCl3, ScCl3, YCl3, ZrCl4 und HfCl4 massenspektrometrisch bestimmt (Tab.1).Diese Werte für ΔH°(dim.) und entsprechende Literaturwerte für weitere Chloride werden zusammenfassend diskutiert. Ist Tb die Siedetemperatur des Chlorids (in °K, bezogen auf die Bildung des Monomeren bei 1 atm Druck), so gilt Q = -ΔH°(dim., Tb)/Tb ≈ 23 cal/°, Mol. Größere Q-Werte werden nur mit den Trichloriden AlCl3, GaCl3, InCl3, FeCl3, TiCl3 und ScCl3 beobachtet, was mit deren Struktur im kondensierten Zustand zusammenhängt.
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  • 76
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    Zeitschrift für anorganische Chemie 410 (1974), S. 293-300 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Quantum Mechanical Ab Initio-Calculations of the Structure and Thermodynamic Data of Crystalline Lithium HydrideA pair potential approximation on the basis of the quantum mechanical FSGO method for calculating the structure and properties of ionic crystals has been applied to lithium hydride. The distance between the ions, the lattice energy and other thermodynamic values have been calculated for the sodium chloride lattice structure in good accordance with experiment. The sodium chloride lattice structure was calculated to be more stable than the ZnS and CsCl lattice structures.
    Notes: Auf der Grundlage des quantenmechanischen FSGO-Ansatzes wird eine Paarpotentialnäherung zur Berechnung der Struktur und der Eigenschaften von Ionenkristallen auf Lithiumhydrid angewendet. Für den NaCl-Gittertyp werden der Ionenabstand, die Gitterenergie und andere thermodynamische Daten in guter Übereinstimmung mit dem Experiment berechnet. Das Zinkblende- und das CaCl-Gitter stellen gegenüber dem NaCl-Gitter energetisch ungünstigere Gittertypen dar.
    Additional Material: 3 Ill.
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  • 77
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    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 410 (1974), S. 316-320 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Komplexe von metallorganischen Verbindungen. XXXVIII. Untersuchung des Anionenaustausches am Trimethylblei(IV)-rhodanid im wäßrigen komplexen SystemDie Verteilung von Me3PbIV zwischen dem Anionenaustauscher Dowex 1×8 und wäßrigen NaSCN- und KSCN-Lösungen wird beschrieben. In wäßriger Phase (bis zu einer Thiocyanatkonzentration von 3 molar) bildet sich nur neutrales Me3PbNCS; die entsprechenden Stabilitätskonstanten werden bestimmt. In der Austauscher-Phase entsteht der anionische Me3Pb(NCS)2--Komplex.
    Notes: The distribution of Me3PbIV between the anion exchange resin Dowex 1 X 8 and aqueous solutions of NaSCN and KSCN was investigated. In the aqueous phase, up to 3 M thiocyanate concentration, only the formation of the neutral species Me3PbNCS was detected and the related stability constant evaluated. Evidence of formation into the resin phase of the anionic Me3Pb(NCS)2- species was obtained.
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  • 78
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    Zeitschrift für anorganische Chemie 410 (1974), S. 269-273 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The Chemical Transport of Platinum with ChlorineExperiments show that the chemical transport of platinum by means of chlorine within a temperature gradient at temperatures below ≈ 1000°K goes into the hot temperature region, but at higher temperatures in the reverse direction. From the thermodynamic discussion it can be seen, that the platinum content of the gas phase at low temperatures is governed by the exothermic formation of Pt6Cl12,g, and at higher temperatures by the endothermic formation of PtCl3,g and PtCl2,g. The platinum content of the gas phase passes a minimum at ≈ 1000°K, if P(Cl2) = 3.5 atm. This result is in agreement with the observed inversion of the transport direction.
    Notes: Experimente zeigen, daß der chemische Transport des Platins mit Chlor im Temperaturgradienten bei Temperaturen unter ≈ 1000°K zur heißeren Zone hin führt, daß er bei Temperaturen oberhalb ≈ 1000°K jedoch in die umgekehrte Richtung geht. Die thermodynamische Diskussion ergibt, daß der Platingehalt der Gasphase bei niederen Temperaturen durch die exotherme Bildung von Pt6Cl12,g, bei höheren Temperaturen aber durch die endotherme Bildung von PtCl3,g und PtCl2,g bestimmt wird. Der Platingehalt der Gasphase geht bei ≈ 1000°K durch ein Minimum, wenn P(Cl2 = 3,5 atm beträgt. Die beobachtete Umkehrung der Transportrichtung ist damit erklärt.
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  • 79
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    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 410 (1974), S. 301-312 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The Divanadates of ThoriumIt is shown that ThV2O7 appears in three polymorphic forms, two of them are crystalline and the third is amorphous. The structural behaviour of these forms is analysed with the aid of thermal, x-ray, and spectroscopic methods. The infrared spectra of the three modifications are discussed in detail.
    Notes: Es wird gezeigt, daß ThV2O7 in zwei kristallinen und einer amorphen Modifikation vorkommt. Das strukturchemische Verhalten dieser Formen wird an Hand von thermischen, röntgenographischen und spektroskopischen Messungen erläutert. Die Infrarotspektren der drei Phasen werden eingehend besprochen.
    Additional Material: 3 Ill.
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  • 80
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    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 405 (1974), S. 63-70 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Sulphito Cobalt(III) Ammines. III. Hydrogensulphito Cobalt(III) AmminesConcentrated acids react with [CoSO3(NH3)5]+ salts hydrogen- sulphitopentaamminecobalt(III) complexes. [Co(HSO3)(NH3)5]Cl2, [Co(HSO3)(NH3)5]Br2 and [Co(HSO3)(NH3)5](HSO4)2·H2O have been isolated. These substances are yellow coloured in contrast to an earlier work which reported red colour.Furthermore, the hydrogensulphitoacidotetreaammine complexes [Co(HSO3)Cl(NH3)4]Cl, [Co(HSO3)Cl(NH3)4]ClO4·H2O, [Co(HSO3)Br(NH3)4]Br and [Co(HSO3) CN(NH3)4]Cl habe been prepared. [Co(HSO3)Br(NH3)4]Br is losing spontaneously HBr forming [CoSO3Br(NH3)4].The neutral complex [Co(HSO3)SO3(NH3)4]·1/2H2O has been obtained from cis- NH4[Co(SO3)2(NH3)4] and HCl.The absorption spectra in the IR, visible and UV region are reported and discussed. The HSO3 group is coordinated to Co through the S atom. The Co—S bond is weaker than in the sulphito complexes as concluded from the RAMAN spectrum. In the new complexes, the hydrogensulphito ligand causes a minor trans effect than the sulphito ligand.
    Notes: Aus [CoSO3(NH3)5]+-Salzen erhält man mit konz. Säuren Hydrogensulfitopentamminkobalt(III)-Komplexe. Isoliert wurden [Co(HSO3)(NH3)5]Cl2, [Co(HSO3)(NH3)5]Br2 und [Co(HSO3)(NH3)](HSO4)2 · H2O. Die Substanzen sind gelb gefärbt im Gegensatz zu früheren Angaben, wonach sie rot sein sollen.Aus geeigneten Sulfitotetramminkobalt(III)-Komplexen wurden in stark saurem Medium die Hydrogensulfitoacidotetrammin-Komplexe [Co(HSO3)Cl(NH3)4]Cl, [Co(HSO3)Cl(NH3)4]ClO4 · H2O und [Co(HSO3)Br(NH3)4]Br dargestellt, welche rot gefärbt sind. [Co(HSO3)Br(NH3)4]Br geht spontan in [CoSO3Br(NH3)4] über. Aus [CoSO3CN(NH3)4] wurde mit halbkonz. HCl das gelbe [Co(HSO3)CN(NH3)4]Cl erhalten.Aus cis-NH4[Co(SO3)2(NH3)4] bildet sich mit halbkonz. HCl der gelbe Neutralkomplex [Co(HSO3)SO3(NH3)4] · 1/2 H2O.Die Absorptionsspektren der Komplexe im Sichtbaren, UV und UR warden mitgeteilt und diskutiert. Die HSO3-Gruppe ist über das S-Atom an Co koordiniert Das RAMAN-Spektrum zeigt, daß die Bindung Co—S schwächer ist als in den Sulfitokobalt(III)-Amminen. In den Komplexen übt die Hydrogensulfitgruppe einen schwächeren trans-Effekt aus als die Sulfitgruppe.
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  • 81
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Studies on Nitrogen Chlorine Compounds. VII. New N-Perchloryl Compounds by Ammono- and Aminolysis of Dichlorine HeptoxideThe reaction of dichlorine heptoxide with ammonia, primary and secondary amines leads to compounds belonging to the class of amides of perchloric acid. The remaining acidic hydrogen atoms on nitrogen could be replaced by metal cations. The compounds were characterized as far as possible by analysis, IR and 1H-NMR spectroscopy. The changing of the bond character between nitrogen and chlorine depending on the substituents on nitrogen is discussed.
    Notes: Die Umsetzung von Dichlorheptoxid mit Ammoniak, primären und sekundären Aminen führt zur Verbindungsklasse der Perchlorsäureamide. Durch doppelte Umsetzung konnten die am Stickstoff noch verbliebenen aziden Wasserstoffatome durch Metallkationen ersetzt werden. Die Charakterisierung der Verbindungen erfolgte, soweit möglich, durch Analyse, IR- und 1H-NMR-Spektroskopie. Die Änderung des Bindungscharakters der NCl-Bindung in Abhängigkeit von den Bindungspartnern am Stickstoff wird diskutiert.
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  • 82
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    Zeitschrift für anorganische Chemie 404 (1974), S. 103-120 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Formation of Organosilicon Compounds. LVI. Reactions of Si- and C-Chlorinated 1,3,5-Trisilapentanes with CH3MgCl(Cl3Si—CCl2)2SiCl2 (1) reacts with an excess of meMgCl (me = CH3) forming me3Si—C≡C—Sime3 (2), Sime4, H2C=C(Sime3)[CH(Sime3)2] (3) as main products and (me3Si)2C—CH(Sime3) and as by-products.The cleavage reaction of (1) to (2) and (3) does not occur when the meMgCl-concentration is lowered. The reaction is started by the formation of a GRIGNARD reagent at a CCl-group in compound (1). Cl3Si—CCl2—SiCl2—CH2—SiCl3 forms with ; me3Si—CCl2—SiCl2—CHCl—SiCl3 forms (me3Si)2C=CH(Sime3). A reaction sequence is given.
    Notes: (Cl3Si—CCl2)2SiCl2 (1) reagiert mit einem Überschuß meMgCl (me = CH3) unter Bildung von me3Si—C≡C—Sime3(2), Sime4, H2C=C(Sime3) [CH(Sime3)2] (3) (Hauptprodukte) und (me3Si)2C—CH(Sime3), (Nebenprodukte).Mit sinkender meMgCl-Konzentration unterbleibt die Spaltung von (1) zu (2) bis (3). Die Umsetzung beginnt mit der Umgrignardierung einer CCl-Gruppe in (1). Cl3Si—CCl2—SiCl2—CH2—SiCl3 reagiert mit meMgCl zu ; me3Si—CCl2—SiCl2—CHCl—SiCl3 zu (me3Si)2C=CH(Sime3). Es wird der Bildungsmechanismus angegeben.
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  • 83
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    Zeitschrift für anorganische Chemie 404 (1974), S. 161-163 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Perfluoroalkylated Acids of Phosphorus. II. On Trifluoromethyl Benzene Phosphinic AcidBis-(trifluoromethyl-benzene) phosphinic acid anhydride 1, easily formed by CF3COOH and C6H5PCl2, yields on reaction with aqueous Na2CO3 solution the sodium salt of trifluoromethyl benzene phosphinic acid 2. The acid itself is isolated by ion exchange as a hygroscopic and highly acidic substance.
    Notes: Das aus CF3COOH und C6H5PCI2 leicht zugängliche Bis-(trifluormethyl-benzol-)phosphinsäure-anhydrid 1 läßt sich mit wäßriger Na2CO3-Lösung zum Na-trifluormethyl-benzol-phosphinat umsetzen, aus dem über Ionenaustausch die freie, hygroskopische und stark acide Trifluormethyl-benzol-phosphinsäure 2 dargestellt werden konnte.
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  • 84
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Hydroxide Groups on Zeolites. II. Number and Properties of Hydroxide Groups on CeNaY and HNaY Zeolites of Different Exchange DegreeThe number of hydroxide groups on CeNaY and HNaY zeolites was examined by D2 exchange, and their properties in dependence of the cation exchange degrees were studied by IR spectroscopy. On CeNaY zeolites there exist six kinds and on HNaY zeolites at least seven kinds of hydroxide groups.On the CeNaY zeolites, the hydroxide groups are produced by dissociative chemisorption of water on Ce3+ ions. Their total number increases continuously with increasing exchange degree. Some of the hydroxide groups are acid BRÖNSTED centers whose number increases with increasing exchange degree and decreases with the temperature of preheating increasing to about 600°C.On the HNaY zeolites, the hydroxide groups are produced by thermal decomposition of the NH+4 ions, by dealumination and interaction of the Al3+ ions produced in this way in the place of cations with water. Above the threshold value of 35% the total number of the hydroxide groups increases very rapidly with increasing exchange degree. One part of the hydroxide groups decreasing with increasing exchange degree acts as acid BRÖNSTED centers. The number of these centers does not decrease until at preheating temperatures above 450°C.
    Notes: An CeNaY- und HNaY-Zeolithen wurden durch D2-Austausch die Zahl und infrarotspektroskopisch die Eigenschaften der Hydroxidgruppen in Abhängigkeit vom Kationenaustauschgrad untersucht. Es existieren an CeNaY-sechs Arten und an HNaY-Zeolithen mindestens sieben Arten von Hydroxidgruppen.An den CeNaY-Zeolithen entstehen die Hydroxidgruppen durch dissoziative Chemisorption von Wasser an Ce3+-Ionen. Ihre Gesamtzahl wächst kontinuierlich mit steigendem Austauschgrad. Einige der Hydroxidgruppen sind saure BRÖNSTED-Zentren, deren Zahl mit steigendem Austauschgrad wächst und mit steigender Vorerhitzungstemperatur bis etwa 600°C sinkt.An den HNaY-Zeolithen entstehen die Hydroxidgruppen durch thermische Zersetzung der eingetauschten NH+4-Ionen und mit wachsendem Austauschgrad zunehmend durch das Herauslösen von Gitteraluminium und Wechselwirkung der so entstehenden Al3+-Ionen auf Kationenplätzen mit Wasser. Die Gesamtzahl der Hydroxidgruppen wächst oberhalb des Schwellenwertes von 35% sehr stark mit steigendem Austauschgrad an. Ein mit steigendem Austauschgrad abnehmender Anteil der Hydroxidgruppen wirkt als saure BRÖNSTED-Zentren, deren Zahl erst bei Vorerhitzungstemperaturen oberhalb von 450°C abnimmt.
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  • 85
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    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 404 (1974), S. 190-198 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Investigation of the Structure of Alkoxoarsenic(V) NitridesUsing electron impact mass spectrometry, it could be proved that NAs(OCH3)2 and NAs(OC2H5)2 form trimeric, tetrameric, pentameric and hexameric units. The trimeric molecule is the main constituent. The cyclic compounds with As—N double bonds are like the phosphazenes. Combined 1H-NMR, Raman and IR data indicate a plane ring for the trimeric. Most of the fragmentations in the ion source of the mass spectrometer are elucidated.
    Notes: Massenspektroskopisch kann nachgewiesen werden, daß NAs(OCH3)2 und NAs(OC2H5)2 Gemische aus trimeren, tetrameren, pentameren und hexameren Moleküleinheiten sind, wobei das Trimere überwiegt. In den Ringen treten As—N-Doppelbindungsanteile auf. Aus 1H-NMR-, RAMAN- und IR-Spektren folgt, daß der Ring in der trimeren Verbindung eben ist. Die Fragmentierungen in der Ionenquelle des Massenspektrometers werden weitestgehend aufgeklärt.
    Additional Material: 4 Ill.
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  • 86
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    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 405 (1974), S. 176-182 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Lattice Vibration Spectra. IX. Pyrite Structure. FIR Spectra and Normal Coordinate Analysis of MnS2, FeS2, and NiS2The FIR absorption spectra of MnS2, FeS2, and NiS2, are recorded in the range of 600 to 30 cm-1. The absorption maxima are assigned to the five IR active optical phonons of the pyrite lattice (k = 0) predicted on the basis of the factor group. Symmetry coordinates and tentative vibration forms of the lattice vibrations are communicated. The large shifting of the absorption maxima of MnS2 (to 220 cm-1) to lower wave numbers are discussed in connection with the strength of the metal sulphur bond.
    Notes: Die FIR-Spektren von MnS2, FeS2 und NiS2 werden im Bereich von 600 bis 30 cm-1 analysiert und den fünf IR-aktiven Translationsschwingungen des Pyritgitters zugeordnet. Die Symmetriekoordinaten der Gitterschwingungen und angenäherte Schwingungsformen konnten aus der Faktorgruppe abgeleitet werden. Die große bathochrome Verschiebung (bis 220 cm-1) der Absorptionsmaxima des MnS2 gegenüber FeS2 wird im Zusammenhang mit der Stärke der Metall-Schwefel-Bindung diskutiert.
    Additional Material: 3 Ill.
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  • 87
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 405 (1974), S. 183-192 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: On Antimony Containing Heterocyclic Systems. I. Molecular and Crystal Structure of 2-Chloro-1,3,6-trithia-2-stibaocane2-Chloro-1,3,6-trithia-2-stibaocane crystallizes in the orthorhombic space group P212121 with cell dimensions a = 9.054, b = 22.610, c = 9.097 Å and Z = 8. The crystal structure has been determined from single crystal X-ray data and refined to a conventional R of 0.038. The eight-membered ring has deformated boat-conformation with 1,5-intraannular Sb—S-interaction. The coordination of the Sb-atom is ψ-trigonal-bipyramidal with axial distances Sb—Cl 2.51 Å, Sb—S 2.86 Å and equatorial distances Sb—S 2.44 and 2.45 Å. The Sb—S-bond is discussed. The structure consists of 14-coordinated molecules densest packed parallel to the x—y-plane and less densely packed perpendicular to this plane.
    Notes: 2-Chlor-1,3,6-trithia-2-stibaocan kristallisiert in der rhombischen Raumgruppe P212121 mit a = 9,054, b = 22,610, c = 9,097 Å und 8 Formeleinheiten in der Elementarzelle. Die Struktur wurde aus Diffraktometer-Einkristalldaten bestimmt und bis zu einem konventionellen R von 0,038 verfeinert. Der 8-Ring liegt in einer deformierten Wannenform mit intraannularer 1,5-Sb—S-Annäherung vor. Die Koordination am Sb ist ψ-trigonal-bipyramidal mit axialen Abständen Sb—Cl 2,51 Å, Sb—S 2,86 Å und äquatorialen Abständen Sb—S 2,44 und 2,45 Å. Die Sb—S-Bindung wird diskutiert. Die Struktur besteht aus 14fach koordinierten Molekeln mit optimaler Packungsdichte parallel zur x—y-Ebene und weniger dichter Packung senkrecht zu dieser Ebene.
    Additional Material: 2 Ill.
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  • 88
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 405 (1974) 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 89
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Solid Reactions in Catalysts and Catalyst Components. I. Solid Reactions in Catalysts for Autothermic Conversion of MethaneSolid reactions in the systems kaolin-NiO, kaolin-α-Al2O3NiO, and kaolin-MgO-NiO are described and investigated by means of X-ray measurements. Data on the reducibility of NiAl2O4 and on the dispersity of nickel on the supports are given. For further characterization of the samples electron-microscopic investigations have also been applied.
    Notes: Es werden die in den Systemen Kaolin-NiO,Kaolin-α-Al2O3-NiO und Kaolin-MgO-NiO ablaufenden Feststoffreaktionen beschrieben. Die Analyse der Reaktionsprodukte erfolgte mittels Röntgenuntersuchungen. Zur Reduzierbarkeit von NiAl2O4 sowie zum Dispersitätsverhalten von Nickel auf Katalysatorträgern werden Angaben gemacht. Elektronenoptische Untersuchungen dienten zur weiteren Charakterisierung der Proben.
    Additional Material: 10 Ill.
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  • 90
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Investigations on Metal Catalysts. I. Structural and Catalytical Investigations on Palladium-Silver PowdersSeveral conditions for preparation of palladium-silver powders are described. By choice of suitable preparation metal crystallites were obtained, in which exists a gradient of concentration with respect to the metals. This gradient determines the behaviour of sorption and catalytical activity, respectively.Characterization of catalysts with regard to their structure takes place by means of X-ray measurements and investigations of sorption (adsorption of N2, chemisorption of CO, sorption of H2), respectively. The catalytical activity of alloys has been measured by means of hydrogenation of benzene.
    Notes: Es werden verschiedene Präparationsbedingungen pulverförmiger Pd-Ag-Katalysatoren beschrieben. Durch Wahl geeigneter Herstellungsverfahren läßt sich in den Metallkristalliten ein Konzentrationsgradient erzeugen, der das Sorptionsverhalten der Legierungen sowie ihre katalytische Aktivität bestimmt.Die Charakterisierung der Proben erfolgte durch Röntgenuntersuchungen sowie Sorptionsmessungen (N2-Adsorption, CO-Chemisorption, Wasserstoffsorption); das katalytische Verhalten der Legierungen wurde mittels der Benzolhydrierung ermittelt.
    Additional Material: 5 Ill.
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  • 91
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 406 (1974), S. 62-68 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Hydrogen Bondings in α-KZnBr3 · 2 H2OThe positions of the hydrogen atoms and the system of hydrogen bondings in the crystal structure of α-KZnBr3 · 2 H2O are discussed. The hydrogen atoms have been located by FOURIER difference synthesis. IR-spectra have given some information about the strength of the various hydrogen bondings O—H … H and O—H … Br.
    Notes: Die Lagen der Wasserstoffatome und die Wasserstoffbrücken-bindungen in der Kristallstruktur des α-KZnBr3 · 2 H2O werden diskutiert. Die Lage der Wasserstoffatome wurde durch eine Differenz-FOURIER-Synthese bestimmt. Die IR-Spektren ermöglichen Aussagen über die Stärke der verschiedenen Wasserstoffbrücken-bindungen O—H … O und O—H … Br.
    Additional Material: 3 Ill.
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  • 92
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Studies on Nitrogen Iodine Compounds. XII. The Reaction of Nitrogen Triiodide-3-Ammonia with Malonic Acid Diethyl Ester in Liquid AmmoniaInteraction of malonic acid diethyl ester with nitrogen triiodide-3-ammonia in liquid ammonia at -33°C leads mainly to diamino malonic acid diamide, iodoform and ethyl carvamate. With a large quantity of nitrogen triiodide, also carbontetraiodide is obtained. Probably diiodo malonic acid diethyl ester is an intermediate product of the reaction.
    Notes: Setzt man Malonsäurediäthylester mit Stickstofftrijodid-3-Ammoniak in flüssigem Ammoniak bei -33°C um, so entstehen vornehmlich Diaminomalonsäurediamid, Jodoform und Carbamidsäureäthylester. Je nach den gewählten Mengenverhältnissen kann auch Tetrajodmethan entstehen. Die Reaktion dürfte über Dijodmalonsäurediäthylester verlaufen.
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  • 93
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 406 (1974), S. 171-177 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Spectroscopic Investigation of Bis-Dihaloboron CompoundsThe data of the IR, RAMAN, 1H- and 11B-NMR spectra of the bis-dihalo-boron compounds I-IV are listed, the vibrations assigned. In the discussion of the results data of alkyldihalogenboranes are included.
    Notes: Die Ergebnisse der IR, RAMAN, 1H- und 11B-KMR-Spektren der Bis-dihalogenbor-Verbindungen I-IV werden angegeben, die Schwingungsfrequenzen zugeordnet. Bei der Diskussion der Ergebnisse werden die Daten von Alkylbordihalogeniden mit einbezogen.
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  • 94
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 406 (1974), S. 167-170 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Preparation of LiAl[P(CH3)2]4 and Silylphosphines H3-x(CH3)xSi—P(CH3)2By metallation of HP(CH3)2 with LiC4H9 (in diglyme, at -40°C) and the subsequent reaction of the LiP(CH3)2 with AlCl3 the compound LiAl[P(CH3)2]4 is obtained (solution in diglyme). The reactions with H3SiBr, CH3SiH2Br, (CH3(2)SiHBr, and (CH3)3)SiCl results in the formation of H3SiP(CH3)2, CH3SiH2,—P(CH32, (CH3)2)SiHP(CH3)2, and (CH3)3Si—P(CH3)2 in large quantities.
    Notes: Durch Metallierung von HP(CH3)2 mit LiC4H9 in Diglym bei -40°C und anschließende Umsetzung des gebildeten LiP(CH3)2 mit AlCl3 wird das LiAl[P(CH3)2]4 zugänglich (Lösung in Diglym). Die Umsetzung mit H3SiBr, CH3SiH2Br, (CH3)2SiHBr und (CH3)3SiCl führt zur präparativen Darstellung von H3Si—P(CH3)2, CH3SiH2—P(CH3)2, (CH3)2SiH—P(CH3)2 (CH3)3Si—P(CH3)2.
    Additional Material: 1 Ill.
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  • 95
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 406 (1974), S. 185-198 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Chemistry of Trifluoromethyl- Sulphur-Nitrogen Compounds. X. Reactions of (CF3S)3-nNHn(CF3S)2NH reacts with SCl2 and S2Cl2 to yield [(CF3S)2N]2S and [(CF3S)2]NS, respectively. In the reaction of Mercaptosulphenic acid chlorides, CClnF3-nSSCl (n = 0, 1, 3) with NH3, CF3SNH2, and (CF3S)2NH, Perhalomethylthiomercaptoamines are obtained. CF3SNH2 and (CF3S)2NH from with FC(O)SCl in 1:1 Mole CF3SNHSC(O)F and (CF3S)2NSC(O)F, respectively. The fluorine of the FC(O)-group in (CF3S)2NSC(O)F can be substituted with bromine or chlorine in the reaction with BX3 (X = Br, Cl). (CF3S)2NSC(O)Cl gives with CH3OH and (C2H5)2NH the expected condensation products. The compounds (CClnF3-nS)3N (n = 0, 1, 2) were investigated by means of ESR spectroscopy. It is possible to obtain CF3S-substituted C—H compounds by irradiation of hydrocarbons in presence of (CF3S)3N. On pyrolysing (CF3S)3N the compound CF3SN=S=NCF3 was isolated among other products. Surprisingly (CF3S)3N reacts with Ph3P to give Ph3P=NSCF3.
    Notes: (CF3S)2NH reagiert mit SCl2 und S2Cl2 zum [(CF3S)2N]2 bzw [(CF3S)2NS]2. Durch Umsetzung der Mercaptosulfensäurechloride CClnF3-nSSCl (n = 0, 1, 3) mit NH3, CF3SNH2, und (CF3S)2NH erhält Perhalogenmethylthiomercaptoamines. Jm Molverhältnis 1:1 bilden CF3SNH2 und (CF3S)2NH mit FC(O)SCl CF3SNHSC(O)F bzw. (CF3S)2NSC(O)F. Das Fluoratom der FC(O)-Gruppe kann im (CF3S)2NSC(O)F mit BX3 (X = Br, Cl) ausgetauscht werden. (CF3S)2NSC(O)Cl liefert mit CH3OH und (C2H5)2NH die erwarteten Kondensationsprodukte. (CClnF3-nS)3N (n = 0, 1, 2) wurden ESR-spektroskopisch untersucht. Durch Bestrahlung von Kohlenwasserstoffen mit (CF3S)3N sind CF3S-substituierte C—H-Verbindungen zugänglich. Nach der Pyrolyse des (CF3S)3N wird neben anderen Produkten CF3SN=S=NCF3 isoliert. Überraschend reagiert (CF3S)3N mit Ph3P zum Ph3P=NSCF3.
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  • 96
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Polymers with Phosphorus-Nitrogen Bonds. III. Thermal Decomposition of Cyclo-di(phosphazanes); Formation of Oligomeric and Polymeric Phosphazane DerivativesOligomeric and polymeric derivatives of the phosphazenes have been prepared by thermal decomposition of the corresponding cyclo-di(phosphazanes). Results of mass and NMR spectroscopic measurements are described. The molecular weight of (NPCl2)n synthetized from (CH3NPCl3)2, has been determined from the torsional modulus as 28 000.
    Notes: Bei der thermischen Zersetzung von (CH3NPCl3)2, [CH3NP·(C6H5)Cl2]2 und (CH3NPF3)2 werden oligomere und polymere Phosphazenderivate gebildet. Ergebnisse der Massen- und Kernresonanz-spektroskopischen Untersuchung werden mit-geteilt. Das Molekulargewicht von (NPCl2)n, dargestellt aus (CH3NPCl3)2, wurde über den Torsionsmodul zu 28 000 ermittelt.
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  • 97
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    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 405 (1974), S. 267-274 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: On the Constitution of a Silicate with the Anion [Si7O19]10-By means of chromatographic and kinetical methods and by mass spectroscopy the existence of a new silicate species in the system N(CH3)4OH—SiO2—H2O, the tetramethylammonium tricycloheptasilicate [N(CH3)4]10[Si7O19] · aq, has been revealed. The corresponding trimethylsilyl ester was isolated.
    Notes: Mit Hilfe chromatographischer und kinetischer Methoden und der Massenspektroskopie wurde im System N(CH3)4OH—SiO2—H2O neben dem bekannten Tetramethylammonium-Dopplevierrringsilicat ein bisher unbekanntes Tetramethylammonium-Tricycloheptasilicat der Formel [N(CH3)4]10[Si7O19] · aq nachgewiesen und der entsprechende Trimethylsilylester [(CH3)3Si]10[Si7O19] isoliert.
    Additional Material: 4 Ill.
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  • 98
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 405 (1974), S. 286-298 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: ESR Studies of Radiation Processes in Phosphate GlassesRadiation processes in phosphate glasses are investigated by ESR and optical measurements. ESR shows a hole-centre in the systems K2O/P2O5 and K2O/MGO/P2O5 which depends on manner and concentration of the cations. Its nature is explained in somewhat a different way than given by BEEKENKAMP or by MIURA and HASEGAWA. Another hole-centre which is independent of cations is discussed in agreement with optical investigations. The electrons set free by radiation react with O2 solved in the glass or with cations. The particels Ag0, Ag2+, Ag+2 have been found and Agn+4 may be present too in the system K2O/MgO/Ag2O/P2O5. The system K2O/MgO/Tl2O/P2O5 shows analogous reactions, but full explanation of the lines could not yet be given.
    Notes: Durch ESR-Untersuchungen und Vergleiche mit optischen Messungen werden Aussagen über die durch Bestrahlung in Phosphatgläsern ablaufenden Vorgänge gemacht. In den Systemen K2O/P2O5 und K2O/MgO/P2O5 wird durch ESR-Messungen ein kationenabhängiges Lochzentrum gefunden, dessen Natur in Abweichung von den Modellen nach BEEKENKAMP und nach MIURA u. HASEGAWA erklärt wird. Ein weiteres kationenunabhängiges Lochzentrum wird in Übereinstimmung mit optischen Untersuchungen gedeutet. Die durch Bestrahlung freigesetzten Elektronen lagern sich an im Glas gelösten Sauerstoff (O2) an oder reagieren mit den Kationen. Im System K2O/MgO/Ag2O/P2O5 werden die Teilchen Ag0, Ag2+, Ag+2 gefunden und Agn+4 wahrscheinlich gemacht. Für das System K2O/MgO/Tl2O/P2O5 gelten analoge Verhältnisse. Eine ausführliche Zuordnung konnte aber dabei noch nicht vorgenommen werden.
    Additional Material: 6 Ill.
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  • 99
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 405 (1974), S. 299-306 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Catalytic Properties of Platinum on Charcoal Carriers of Different Pore Structure5% Pt/carbon catalysts have been studied in respect to the influence of carrier pore structure and Pt dispersity on the catalytic properties. Test reactions were the dehydrogenation of cyclohexane and the dehydrocyclization of three isomeric octanes.A biporous carrier characteristic results in optimal activity for cyclohexane dehydrogenation. For the octane dehydrocyclization a strong influence of pore structure on selectivity has been observed; microporosity strongly reduces the selectivity.
    Notes: An 5proz. Platin-Kohle-Katalysatoren wurde der Einfluß der Porenstruktur des Trägers und der Dispersität der Aktivkomponente auf die katalytische Eigenschaften untersucht.Als Testreaktionen wurden die Cyclohexandehydrierung und die Dehydrocyclisierung von drei isomeren Octanen gemessen und festgestellt, daß Träger mit biporösen Eigenschaften optimale Aktivität gegenüber der Cyclohexandehydrierung haben. Bei der Dehydrocyclisierung der Octane wurde ein großer Einfluß der Porenstruktur auf die Selektivität der Reaktion beobachtet, wobei mikroporöse Träger die Selektivität stark herabsetzen.
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  • 100
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 406 (1974), S. 101-104 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Contributions to the Chemistry of Transition Metal Diolefin Complexes. I. On the Electro-Synthesis of Iron Complex Compounds of Noncyclic 1,3-Di-olefinsThe cathodic reduction of iron trisacetylacetonate in presence of dienes and triphenylphosphine gives complexes of the typ (dien)2 FeP(C6H5)3. The synthesis of bis(1,3-butadiene)-triphenylphosphine iron and bis(isoprene)triphenylphosphine iron are described.
    Notes: Die kathodische Reduktion von Eisentrisacetylacetonat in Gegenwart von Dienen und Triphenylphosphin führt zu Komplexen des Typs (Dien)2FeP(C6H5)3. Die Darstellung von Bis-(1,3-butadien)-tri-phenylphosphineisen und Bis-(isopren)-tri-phenylphosphineisen wird beschrieben.
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