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  • 1970-1974  (4,021)
  • 1965-1969  (4,229)
  • 1920-1924  (3,032)
  • 1880-1889  (6,746)
  • Inorganic Chemistry  (17,840)
  • Electron Microscopy
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Year
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Virchows Archiv 364 (1974), S. 111-127 
    ISSN: 1432-2307
    Keywords: Electron Microscopy ; Coronary Arteries ; Atherosclerosis ; Aging ; Smooth Muscle
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The coronary arteries were studied by electron microscopy in normal rats weighing 65 to 535 gm; fixation was accomplished by perfusion for 20 min at 110–130 mm Hg. In rats of all ages (but especially in the oldest) the arterial wall contained deposits of abnormal intercellular material, consisting of granules, vesicles, myelin figures and other debris. These deposits were present in the intima and media, but rare in the adventitia; there was suggestive evidence that medial cells phagocytized some of the material. The adventitia was characterized by 1–4 layers of cells with extremely thin protoplasmic expansions wrapped around the vessel (“veil cells”) and containing lysosome-like bodies as well as phagosomes. These findings, taken as a whole, suggest the following sequence of events. During normal life, the media produces cellular debris, by cell death as well as by fragmentation of cellular processes; part of these debris are phagocytized by smooth muscle cells, part diffuse outward to the adventitia where they are taken up by specialized cells (the “veil cells”). However, due to relative inadequacy of phagocytosis in the media, the debris continue to accumulate and form intercellular deposits that increase with age. It is possible that this natural phenomenon may by itself set a maximal limit to the life-span of the arterial wall.
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Virchows Archiv 363 (1974), S. 249-258 
    ISSN: 1432-2307
    Keywords: Hypertensin (Angiotensin) ; Catecholamins ; So-Called Epinephrine Myocarditis ; Rat Heart ; Optical Microscopy ; Electron Microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Pathomorpliological comparative studies on structural damage to rat cardiac muscle following administration of hypertensin and arterenol, with and without pretreatment with reserpine to empty the catecholamine reserves were performed. The question is whether and to what degree angiotensin induced cardiac damage, which is viewed microscopically as the so-called epinephrine myocarditis, can be regarded as an indirect catecholamine effect. The following could be deduced: 1. Hypertensin causes a damage pattern similar to that of arterenol as seen under the light microscope and corresponds to the so-called epinephrine myocarditis. 2. The electron microscope demonstrates definite differences in the pattern of damage to the myocardium: hypertensin affects primarily the mitochondria, while arterenol affects the myofibrils. 3. Hypertensin and arterenol damage mainly the subendocardial tissue of the left heart: hypertensin affects more the region of the base of the left ventricle, arterenol more the region of the left ventricle apex. 4. Pretreatment with reserpine blocks the damaging effects of hypertensin in the rat heart for 12 hours. After 24 hours the full picture of the damage pattern has reappeared. Arterenol is lethal to animals pretreated with reserpine. 5. The pathogenesis of the damaging effects of hypertensin on rat cardiac muscle is discussed.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Lung 150 (1974), S. 185-189 
    ISSN: 1432-1750
    Keywords: Paraquat Poisoning ; Morphology ; Electron Microscopy ; Light Microscopy ; Letal Course ; Human Lung ; Lung Fibrosis ; Proliferative Alterations ; Degenerative Alterations ; Pathogenesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Morphological alterations in the lungs of 3 cases of paraquat intoxication with prolonged lethal course (10, 11, and 25 days) are reported. Combined light-and electronmicroscopic studies reveal that 10 and 11 days after the ingestion of paraquat the endothelium of the occassionally congested capillaries is intact. The basal membranes have only scarce alterations. They are sometimes naked because of shadding of both types of pneumocytes with severe alterations, e.g. lipid accumulation in the cytoplasm. In the vast alveolar edema, red blood cells, some round cells, strands of fibrin, and lamellar cell debris are seen. There are also varying amounts of polymorphnuclear leucocytes and alveolar macrophages with many phagolysosomes and cytosegresomes. Fibroblasts with lipid droplets between the extensive RER form varying amounts of collagen fibrils in the alveolar and sometimes in the very edematous interstitial space. Sometimes surrounded by collagenous material, they thus devoured by macrophages. 25 days after paraquat intoxication a severe alveolar fibrosis, focal interstitial fibrosis, and areas with atelectasis are found. Due to artificial respiration and changed ventilation mechanics, there were large areas with hemorrhage and a honeycomb-like structure of the remaining lung parenchyma. The pathogenesis of the degenerative and proliferative lung alterations is briefly discussed.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Calcified tissue international 16 (1974), S. 109-127 
    ISSN: 1432-0827
    Keywords: Dentinogenesis ; Diphosphonates ; Calcification ; Collagen ; Electron Microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Abstract The effects of high doses of ethylene-1-hydroxy-1,1-diphosphonate (EHDP) were investigated at the light microscopic and subcellular level. The administration of EHDP at a concentration of 7.5–10 mg P/kg body weight/day over a short period of time resulted in complete inhibition of crystal formation in predentin and pre-enamel. An increased predentin width was observed and within newly-formed predentin areas the formation ofcollagen fibrils was grossly disturbed. In addition, fine precipitates appeared in the ground substance. The presence of unusual thread-like elements within specific bodies in the cytoplasm of the odontoblastic processes may be indicative of an interference by EHDP in e.g. the synthesis of precollagen. The possibility of an inhibition by EHDP of the extracellular aggregation of collagen molecules is also discussed. EHDP further inhibited crystal formation within dentinal globules. Functioning ameloblasts were grossly affected in EHDP-treated rats, and it is suggested that this is related to an inhibition of crystal formation in pre-enamel.
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  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Archives of microbiology 98 (1974), S. 271-274 
    ISSN: 1432-072X
    Keywords: Proteus vulgaris ; Bacteriocin ; Electron Microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The intracellular development of a bacteriocin in a strain of Proteus vulgaris was investigated. Particles which resemble the bacteriocin make their appearance in the cell after 60 min induction with mitomycin C. At this stage they appear as broad bands of tightly-packed phage tail-like structures. With longer periods of induction the bands are disrupted to liberate individual phage tail-like particles.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Acta neuropathologica 30 (1974), S. 33-41 
    ISSN: 1432-0533
    Keywords: Organic Mercury Compound ; Late Pathological Changes in Peripheral Nerves ; Electron Microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Wistar strain of male rats of 100–110 g were used, 5 for an experimental and 5 for control group. 1 mg of organic mercury (methyl methylmercuric sulfide: CH3HgSCH3) was given by mouth each day for 10 days (total dose 9–10 mg) to the experimental group. 600 days afterwards the experimental and control rats were killed. Only the peripheral nerves showed changes, small myelinated nerve fibres with thick myelin sheaths in groups. Around these fibres occurred extremely small myelinated nerve fibres and isolated large unmyelinated fibres, and appeared to be regenerated fibres. Destruction of myelin sheaths and cavity formation in the axons were observed in these fibres. The changes in the axons were remarkable at the nodes of Ranvier.
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  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Acta neuropathologica 30 (1974), S. 11-24 
    ISSN: 1432-0533
    Keywords: Ataxia ; Rabbit ; Degeneration ; Cochlear Nuclei ; Electron Microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary This hereditary animal ataxia is selective in its sites of involvement within the nervous system, which include principally the central cerebellar, vestibular and cochlear nuclei. Ultrastructural detail has been described for central cerebellar and vestibular nuclei. Herein the cochlear complex of 18 rabbits with this ataxic condition (ax/ax from the strain AX of the Jackson Laboratory) have been examined. The gene is a lethal one, but the animals were used before they became moribund and between 7 and 57 days after the onset of symptoms. By light microscopy nine cell types (Osen, 1969a, b; 1970) have been identified in the cochlear nuclei of the cat. That distribution can also be identified in electron micrographs of rabbit cochlear nuclei, providing there is a singular opportunity to compare cellular vulnerabilities within the ataxic condition, and establish the principal features of associated neuropil alterations. The cochlear nuclei, cerebellar cortex and central nuclei, and the vestibular nuclei, arise from the ependyma of the rhombic lip of the fourth ventricle, making them close allies in their genetic origins. Pathological alterations were evident in scattered neurons from all nuclear sources by 7–15 days following symptom onset. At 15 days the number of altered neurons evident in electronmicrographs had increased markedly, cells becoming involved at a more rapid pace than those already affected could be removed. Much glycogen is evident from 7 days onwards in both neuropil and neurons. It occurs in considerable amounts in astrocytic processes and less abundantly in endbulbs and somata. By 20 to 25 days spongioform changes in neuropil are prominent, and thereafter the extracellular spaces coalesce to produce a lacunar appearance showing little glycogen. It would appear, therefore, that all neuron types, the endbulbs, and the astrocytic processes are markedly involved simultaneously in the spongioform transformation which features this type of ataxia. Involvement of cochlear nuclei only differs in pathological detail from that found at the other involved sites, and the differences seen relate principally to the architectonics of the nuclei, including size and density of the packing of contained elements.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Acta neuropathologica 30 (1974), S. 73-84 
    ISSN: 1432-0533
    Keywords: GM1 Gangliosidosis ; Friesian Calves ; Inborn Metabolic Error ; Histochemistry ; Electron Microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Histoenzymic and ultrastructural alterations in the brains of seven calves with GM1 gangliosidosis are described. A decreased oxidative enzyme activity in neurons was accompanied by an increase in acid phosphatase activity. Membranous cytoplasmic bodies were present in neurons and glia. The periodicity of the membranes was about 5.5 to 6.0 nm. Electron-dense, membrane-bound inclusions were present in perithelial cells. The lesions were compared with those of gangliosidoses in other species.
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  • 9
    ISSN: 1432-0533
    Keywords: Progressive Multifocal Leukoencephalopathy ; Hirano Bodies ; Papova Virus ; Paramyxovirus-like ; Nuclear Bodies ; Electron Microscopy ; Neurofibrillary Tangles
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary We have identified three structures that have not previously been reported in electron microscopic examinations of brain from patients with PML: 1. coiled nuclear bodies that may possibly represent tubular paramyxovirus nucleocapsids, 2. Hirano bodies and 3. Neurofibrillary tangles. The paramyxovirus-like material is interesting in view of reports of a transition between nuclear bodies and tubular paramyxovirus nucleocapsids and because of a possible interaction between syncytiogenic paramyxoviruses and Papova viruses in the pathogenesis of SSPE and PML. A study of the Hirano bodies in this case, taken in conjunction with the findings of others leads us to believe that these structures are formed from an overgrowth of neurofilaments. The presence of tangled masses of neurofilaments in the processes of neurons also seen in the present case is consistent with this hypothesis.
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  • 10
    Electronic Resource
    Electronic Resource
    Springer
    Acta neuropathologica 27 (1974), S. 201-213 
    ISSN: 1432-0533
    Keywords: Infantile Neuroaxonal Dystrophy ; Spheroids ; Perikaryon ; Electron Microscopy ; Membranous Profiles ; Dense Bodies ; Protein Syntheses
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Electron microscopic findings of a cortical biopsy from a four-year-old child suffering from muscular weakness and psychomotor retardation are presented. Morphological evidence obtained in this study suggests a unique pathogenetic mechanism underlying INAD. The spheroids appear to be caused by an accumulation of a macromolecular substance synthesized in the neuron and transported to the nerve endings. The abnormal substance initially takes the form of an amorphous material, it eventually aggregates into highly characteristic angulated membranous profiles. The selective involvement of the nerve endings, synapses and motor end plates in this disease suggests a derangement of the metabolic pathway in the synthesis or packaging of the neurotransmitters or their receptors.
    Type of Medium: Electronic Resource
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  • 11
    Electronic Resource
    Electronic Resource
    Springer
    Archives of microbiology 97 (1974), S. 27-38 
    ISSN: 1432-072X
    Keywords: Mass Mating ; Electron Microscopy ; Cell Fusion ; Membrane Structure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The process of mating reaction of Saccharomyces cerevisiae was studied by electron microscopy. Prior to the dissolution of the part of the cell walls separating the conjugating pair of cells, the thinning of the electron transparent layer of the cell wall occurs at the part toward which the nuclei are migrating. After the dissolution of the cell walls of the conjugating cells, the cell membranes become associated with each other, then to be broken and rejoined. The first diploid bud emerges from about the middle of the zygote. The morphological changes during the mating reaction are discussed in relation to the biochemical changes so far known.
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  • 12
    Electronic Resource
    Electronic Resource
    Springer
    Archives of microbiology 98 (1974), S. 311-329 
    ISSN: 1432-072X
    Keywords: Dictyostelium discoideum ; Inorganic Polyphosphate ; Electron Microscopy ; Enzymes ; Polyphosphate Metabolism ; Cellular Slime Mold ; Polyphosphatase ; Polyphosphate-ADP-Phosphotransferase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The concentration of inorganic polyphosphates in Dictyostelium discoideum was low in the amoebae. A ca 5-fold increase took place during the early stages of multicellular development and was followed by a decrease during the intermediate stages. Electron micrographs showed the presence of electron dense material in all parts of the differentiating cells. The substance was most frequently observed in various types of vacuoles. Two enzymes of polyphosphate metabolism were identified and studied in cell-free extracts: a polyphosphatase and a polyphosphate-ADP-phosphotransferase. No polyphosphate-glucose-phosphotransferase or polyphosphate-AMP-phosphotransferase activities were observed in the extracts. The specific activity of the polyphosphatase, pH optimum 7.6, was ca 30 nmol Pi·min-1·mg protein-1 at all stages of development. The enzyme activity was not inhibited by 0.01 M orthophosphate. The polyphosphate-ADP-phosphotransferase, pH optimum ca 7.7, was studied in the direction of ATP. The enzyme specific activities were very low, about 0.2 nmol P·min-1·mg protein-1, and rather constant during differentiation. The enzyme activity was inhibited by orthophosphate and by excess ADP. It was concluded that the polyphosphate-ADP-phosphotransferase did not contribute significantly to the formation of ATP during multicellular development, and that polyphosphate did not act as a phosphagen in the differentiating cellular slime mold. It was suggested that polyphosphate served as a phosphate store and as a means of regulating the intracellular orthophosphate concentration during development.
    Type of Medium: Electronic Resource
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  • 13
    Electronic Resource
    Electronic Resource
    Springer
    Archives of microbiology 99 (1974), S. 281-294 
    ISSN: 1432-072X
    Keywords: Spirochete ; Artemia ; Brine Shrimp ; Electron Microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract 1. A spirochete which occurs in tissues of the brine shrimp,Artemia salina, was studied by light microscopy and transmission electron microscopy. A total of seven infected shrimps were encountered. 2. Under darkfield illumination, most spirochete cells inArtemia blood were 6–13 μ long and 0.3–0.4 μ wide. Coiling was variable and often irregular. 3. When tissues of the maxillary gland (kidney) and nearby organs were examined by electron microscopy, spirochete cells were found in both extracellular and intracellular locations. These microbes possessed the ultrastructural features typical of members of the Order Spirochaetales: a) a slender protoplasmic cylinder (0.18 μ average diameter), b) axial fibrils (150 A average diameter), and c) an outer envelope or sheath (approximately 75 A thick). 4. Counts made of the number of axial fibrils evident in transverse sections of spirochete cells were consistent with the hypothesis that this spirochete has a 1-2-1 arrangement of axial fibrils. 5. Non-spiral forms were observed in the haemocoel and in the lumen of the maxillary gland.
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  • 14
    Electronic Resource
    Electronic Resource
    Springer
    Archives of microbiology 100 (1974), S. 145-162 
    ISSN: 1432-072X
    Keywords: Complex Flagella ; Fine Structure ; Electron Microscopy ; Optical Diffraction ; Flagellin ; Flagellar Motion
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Zusammenfassung Zellen von Rhizobium lupini H 13-3 besitzen 5–10 peritrich inserierte komplexe Geißeln, deren Feinstruktur durch Hochauflösungs-Elektronenmikroskopie und lichtoptische Diffraktion analysiert wurde. Das Geißelfilament hat einen Durchmesser von 160 Å und besteht aus einem zylindrischen Kern (Durchmesser ca. 110 Å), der fest von drei Bändern einer helikalen Scheide umgeben ist. Die Scheidenbänder sind 49 Å breit, durch 49 Å-Intervalle voneinander getrennt und haben eine Steigung von 31°. Die komplexen Geißelfilamente bestehen aus einem 43 000-Dalton-Protein, das den Kern und die helikale Scheide aufbaut. Beide gehen übergangslos aus dem proximalen Geißelhaken hervor, der einen Durchmesser von 150 Å und eine Länge von 600 bis 800 Å hat. Die Diffraktionsanalyse des Geißelhakens zeigte eine helikale Grundanordnung von globulären Untereinheiten, die ein Oberflächengitter von 5 parallelen Schrauben (Steigung 29° bzw. 33°) bilden, von denen jede fast 11 Untereinheiten pro Helixungang trägt. Die komplexen Geißeln von R. lupini H 13-3 und Pseudomonas rhodos [Schmitt et al.: J. Bact. 117, 844–857 (1974)] sind ein neuer Typ von Bakteriengeißeln. Sie zeigen deutliche Übereinstimmung in der Feinstruktur, der festen Verbindung von helikaler Scheide und Geißelhaken sowie in der Fragilität ihrer Filamente; sie unterscheiden sich deutlich im Molekulargewicht der Flagellinmonomeren (43 000 bzw. 55 000). Zellen von R. lupini H 13-3 führen schnelle, vibrierende Translationsbewegungen aus. Mögliche Mechanismen der Bewegung komplexer Geißeln werden diskutiert.
    Notes: Abstract Cells of Rhizobium lupini H 13-3 possess 5 to 10 peritrichously inserted complex flagella, which were analyzed by high resolution electron microscopy and by optical diffraction. The flagellar filament has a diameter of 160 Å; it consists of a cylindrical core (diameter approximately 110 Å) surrounded by three close-fitting bands of a helical sheath. The helical bands are 49 Å wide, separated by axial intervals, 49 Å wide, and run at an angle of 31°. Complex filaments consist of a 43 000-dalton protein representing the core and the helical sheath. These originate from the proximal hook, which has a diameter of 150 Å and a length of 600 to 800 Å. The diffraction analysis of the hook showed a helical arrangement of globular subunits forming a surface of 5 parallel “small-scale” helices (pitch-angles 29° and 33°, respectively), each carrying almost 11 subunits per period. The complex flagella of R. lupini H 13-3 and Pseudomonas rhodos [Schmitt, et al.: J. Bact. 117, 844–857 (1974)] represent a novel type of bacterial flagella. There is agreement in their fine structures, in the intimate connection of the helical sheath and the core, and in the fragility of their filaments. Thery are clearly distinguished by the molecular weights of their flagellin monomers (43 000 and 55 000, respectively). Cells of R. lupini H 13-3 show fast, vibrating, translational motions. Possible mechanisms of complex flagellar motion are discussed.
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  • 15
    ISSN: 1432-072X
    Keywords: Bdellovibrio bacteriovorus ; Spirillum serpens ; Freeze Fracture ; Electron Microscopy ; Ultrastructure ; Membrane Damage ; Organismic Associations
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The freeze-fracture technique and electron microscopy have been used to demonstrate that localized damage is inflicted upon the cytoplasmic membrane of Spirillum serpens VHL within 20 to 30 min after the start of its association with Bdellovibrio bacteriovorus 109D. This damage is not observed in uninfected Spirillum cells, nor in infected cells within the first 10 min. This damage takes the form of a “blister” which, when viewed stereoscopically in electron micrographs, is seen to project toward the interior of the Spirillum cell. Shortly after its formation, the blister becomes elaborated into a series of ridges which may assume forms ranging from an elaborate spiral to a series of loops or knots. The formation of a blister is shown to involve both the inner and outer leaves of the membrane bilayer, and evidence is presented to indicate that the blister site corresponds to the site of attachment of the Bdellovibrio cell. The hypothesis is proposed that this ultrastructural damage is the cytological basis for the controlled and localized leakage through the cytoplasmic membrane into the periplasmic space of the Spirillum cell at locations adjacent to the Bdellovibrio cell. It is suggested that this localized membrane damage may be the ultrastructural basis for the high efficiency with which bdellowvibrios are known to incorporate cytoplasmic materials from the other bacteria in whose periplasmic spaces they develop.
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  • 16
    Electronic Resource
    Electronic Resource
    Springer
    Archives of microbiology 100 (1974), S. 307-328 
    ISSN: 1432-072X
    Keywords: Citrate Lyase ; Subunit Structure ; Electron Microscopy ; Reaction Inactivation ; Rhodopseudomonas gelatinosa ; Phototrophic Bacteria
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract 1. Citrate lyase (EC 4.1.3.6) from Rhodopseudomonas gelatinosa has been purified to homogeneity by protamine sulfate fractionation, chromatography on DEAE-Cellulose and gel filtration. The final enzyme preparation had a specific activity of 138 units per mg of protein and was purified 43-fold over the crude extract. Analysis of citrate lyase by sedimentation equilibrium experiments and gel filtration gave molecular weights of 530000 and 560000, respectively. 2. Electron microscopic investigations of negatively stained enzyme molecules and image analysis showed that citrate lyase is composed of six large and six small subunits; they are arranged in two hexagonal rings lying face to face, each containing, in alternating sequence, three large and three small subunits. The enzyme molecule is 160 Å in diameter and about 100 Å thick. 3. Treatment with sodium dodecylsulfate and mercaptoethanol dissociated citrate lyase into three proteins. Protein III (small subunit) had a molecular weight of 30000 and contained the pantothenate; protein II (large subunit) had a molecular weight of 61000; protein I (M r =97000) was probably an aggregate of II and III. 4. Based on the results obtained a model of citrate lyase was constructed. 5. Purified citrate lyase was obtained from R. gelatinosa in a deacetylated and largely oxidized form. The enzyme was activated by reduction with dithiothreitol (3 mM) and subsequent acetylation with acetic anhydride (1.75 mM). 6. The enzyme was subject to reaction inactivation, the extent of which depended on the concentration of Mg2+.
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  • 17
    Electronic Resource
    Electronic Resource
    Springer
    Acta neuropathologica 30 (1974), S. 271-276 
    ISSN: 1432-0533
    Keywords: Intracranial Teratoma ; Electron Microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A massive congenital benign teratoma grossly replacing the cerebral hemispheres has been examined by light and electron microscopy. The tumor contained tissues derived from all three germ layers. The cerebellum showed morphological features suggesting a state of maturation equivalent to that of 20 to 25 weeks of gestation. The tumor is discussed in the light of present theories on the pathogenesis of teratomas.
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  • 18
    Electronic Resource
    Electronic Resource
    Springer
    Acta neuropathologica 30 (1974), S. 315-328 
    ISSN: 1432-0533
    Keywords: Human Adenovirus Type 12 ; Sprague-Dawley Rats ; Intracerebral Inoculation ; Medulloepitheliomatous Neoplasm ; Giant Tumor Cells ; Electron Microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Solid medullary brain and spinal cord neoplasms developed in all 10 offspring of an outbred Sprague-Dawley rat, between 37 and 99 days after a single postnatal (within 24 hrs) inoculation of 0.05 ml of human adenovirus type 12, 103.5–104.5 TCID50 HeLa cells/0.1 ml in the left frontal lobe. Seven rats developed multicentric neoplasms in both hemispheres and in peri-aqueductal areas of the brain stem, one of which was associated with an incipient spinal cord tumor in the sacral segment. One rat developed a solid tumor involving the right parieto-occipital region. The remaining two cases were solid spinal cord tumors arising from the dorsal half of the thoracolumbar segments. The remarkably uniform microscopic appearance was designated as a counterpart of human embryonic neuronal neoplasms. Characteristic neuronal and multinucleated giant cells emerged throughout the tumor tissue with argentaffine, neurofibril-like cytoplasmic expansions and a unique cilium (a 9+0 pattern of tubules) associated with a pair of centrioles. This cilium morphology was also a hallmark of the majority of tumor cells that formed characteristic pseudorosettes. The occasional emergence of two sets of cilia and centrioles in monstrous cells suggested probable modes of cytogenesis in relation to cessation of abnormal cell division.
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  • 19
    ISSN: 1432-0533
    Keywords: Myxopapillary Ependymoma ; Tissue and Organ Culture ; Electron Microscopy ; Basement Membrane
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Explants of a myxopapillary ependymoma were grown on collagen-coated coverslips and in organ culture systems using gelfoam sponge matrices and Millipore filter platforms. The tumor cultured on collagen-coated coverslips initially exhibited the cytologic features of simple uni- and bipolar glial cells and later developed an epithelial-like pattern. Delicate branching of argyrophilic cell processes was demonstrated in Bodian preparations. In organ cultures, the tumor architecture was well preserved for approximately 4 weeks, and mitotic figures were present. Invasion of the sponge foam matrix was seen. Later cultures demonstrated progressive perivascular sclerosis and hyalinization. By electron microscopy, the tumor cells in organ culture systems retained the major fine structural characteristics of the original neoplasm up to 27 daysin vitro. The most striking feature in the late stages was the extensive increase and reduplication of basement membrane material, which appeared related to the increase of collagen fibrils in the extracellular space.
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  • 20
    Electronic Resource
    Electronic Resource
    Springer
    Acta neuropathologica 27 (1974), S. 43-53 
    ISSN: 1432-0533
    Keywords: Oncocytes ; Adenohypophysis ; Pituitary Adenoma ; Secretory Granules ; Electron Microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A light and electron microscopic study was undertaken on 3 surgically removed non-tumorous adenohypophyses and 16 pituitary adenomas. Numerous oncocytes have been found in 2 non-tumorous adenohypophyses and in 6 pituitary adenomas including 1 chromophobe adenoma which was composed almost exclusively of oncocytes. Thus, it seems that the occurrence of oncocytes in the anterior pituitary cannot be considered a rare finding. The distinctive feature of oncocytes is the abundance of mitochondria in their cytoplasm. This alteration can be so extensive that the entire cytoplasm is filled with mitochondria leaving only a small area for the remaining cytoplasmic organelles. Oncocytes arise from adenohypophysial cells. This transformation is gradual and is not restricted to one particular cell type. In the early phases of development of oncocytes the secretory granules are well preserved. Thus, hormone secretion is presumably maintained. It seems conceivable, however, that in the more advanced phases of evolution of oncocytes, when the secretory granules decrease in number, hormone production is diminished or stopped. Further investigations are, however, required to elucidate in detail the functional activity of oncocytes. It remains to be established whether mitochondrial accumulation is principally due to increased formation or delayed breakdown. As some mitochondria show signs indicating division it appears that multiplication of mitochondria is the underlying mechanism resulting in their significant increase. However, the possibility cannot be excluded that the life span of mitochondria is prolonged and mitochondrial longevity plays an important role in causing transformation of adenohypophysiocytes into oncocytes.
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  • 21
    ISSN: 1432-0533
    Keywords: Neuroaxonal Dystrophy ; Infantile Autonomi Nervous System ; Electron Microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The autonomic nervous system is studied by electron microscopy for the first time in two siblings born of North African consanguineous parents and affected by infantile neuroaxonal dystrophy. The changes already reported in dystrophic axons of the central and peripheral nervous system, are seen in the myenteric plexus of rectum mucosa. The authors stress the diffuse involvement of the nervous tissue in this degenerative disorder of still unknown nature.
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  • 22
    ISSN: 1432-0533
    Keywords: Craniopharyngioma ; Tissue Culture ; Electron Microscopy ; Enzyme Histochemistry ; Keratine ; Enamel ; Rosenthal Fibers
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Electron optical and enzyme histochemical investigations carried out on four craniopharyngiomas and their tissue cultures demonstrated that the tumour elements are keratinizing epithelial cells, plenty of tonofilaments, glycogen granules, mitochondria and desmosomes. Their ultrastructural and histochemical characteristics are the same in every part of the tumour (solid; cystic; “adamantinoma-like”). In the keratinizing cells, the reactions for non-specific esterases were high positive. The ultrastructural characteristics of the tumour cells grownin vitro are the same as thosein situ; the cells remain attached to one another by desmosomes and retain their capacity to produce keratine. This therefore seems to be a primary characteristic of the tumour cells and not a secondary dysmetabolic disturbance. Calcium was found onlyin situ. That the tumour cells may produce enamelin situ seems to be possible, but it could not be confirmed with certainty. The glial proliferation which is always presentin situ, is reactive and not neoplastic; thein vitro new built cell colonies consist only of epithelial elements.
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  • 23
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    Acta neuropathologica 29 (1974), S. 45-55 
    ISSN: 1432-0533
    Keywords: Experimental Neural Tumours ; Ethylnitrosourea ; Electron Microscopy ; Lysosomes ; Acid Phosphatase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A single intravenous injection of 30 mg of N-ethyl-N-nitrosourea per kg of body weight was administered to pregnant BD-IX rats on the 15th day of gestation. The neural tumours which developed in 97.5% of the offspring were gliomas and schwannomas. The demonstration of acid phosphatase in the neoplastic and reacting cells of these tumours was carried out at fine structural level. The enzyme activity was localised in lysosomes and in the innermost cisternae of the Golgi complexes. High acid phosphatase activity was related not only to degeneration, necrosis and phagocytosis but also to cellular differentiation and anaplasia.
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  • 24
    ISSN: 1432-0533
    Keywords: Steele-Richardson-Olszewski Syndrome ; Progressive Supranuclear Palsy ; Neurofibrillary Tangles ; Electron Microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The neurofibrillary tangles found in the neurons of a case of Steele-Richardson-Olszewski syndrome were studied by electron microscopy. Both the flame-shaped and globose type of tangles were present. The neurofibrillary tangles were composed of bundles of straight tubules measuring approximately 150 Å in diameter. This ultrastructural appearance of the tangles in Steele-Richardson-Olszewski syndrome is different from the appearance of tangles found in other neurological disorders and is probably indicative of intraneuronal accumulation of a new type of fibrous protein.
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  • 25
    ISSN: 1432-0533
    Keywords: Polyneuropathy Associated with Adie's Syndrome ; Sural Nerve ; Electron Microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The sural nerve of a woman of 35 with chronic polyneuropathy and Adie's syndrome was examined by electron microscopy. Myelinated nerve fibres were absent and there was marked reduction in the number of unmyelinated fibres. Onion bulb formation was not observed. Collagen fibres occupied the intercellular spaces.
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  • 26
    ISSN: 1432-0533
    Keywords: Experimental Neural Tumours ; Ethylnitrosourea ; Electron Microscopy ; Thiamine Pyrophosphatase ; Adenosine Triphosphatase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The fine structural localisation of thiamine pyrophosphatase and adenosine triphosphatase was carried out in gliomas and schwannomas induced transplacentally by N-ethyl-N-nitrosourea. The activity of thiamine pyrophosphatase was observed in the Golgi complexes and appeared to be directly related to cellular differentiation and reactive changes. The Mg2+-dependent adenosine triphosphatase was localised at the cell membrane, in the pinocytotic vesicles of various cells and in the basement membrane of some capillaries. This enzyme, showing high activity in differentiated cells, indicated the activity of membrane-bound cellular transport.
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  • 27
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    Acta neuropathologica 29 (1974), S. 211-222 
    ISSN: 1432-0533
    Keywords: Experimental Gliomas ; Ethylnitrosourea ; Electron Microscopy ; Virus-like Particles
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Two unusual, intracytoplasmic structures, resembling viruses, are described in experimental gliomas which were induced transplacentally on the 15th day of gestation in BD-IX rats by a single intravenous injection of 30 mg of N-ethyl-N-nitrosourea per kg of body weight. These structures are tubules within the lumen of the endoplasmic reticulum and large coated vesicles in the Golgi region. The tubules are of indeterminate length and have inner and outer walls of 9–11 nm and 20–22 nm respectively. The large coated vesicles are 80–90 nm in diameter and their outer surface is covered by regular, equidistant spikes of 12–15 nm in length. The vesicles are closely related to the Golgi complexes, from which they appear to originate. The intracisternal tubules and large coated vesicles share certain morphological features both with viruses and with normal cell organelles. The origin and significance of these structures are discussed.
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  • 28
    ISSN: 1432-0533
    Keywords: Jimpy Mouse ; Electron Microscopy ; Mouse Mutant ; Myelination ; Axonal Growth
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A quantitative study of the myelination and axonal growth in the corpus callosum and posterior columns of the spinal cord in the Jimpy mouse gave the following results: The reduction in the number of myelinated fibers is much more important in regions with late myelination, e.g. corpus callosum and pyramidal tracts than in the previously myelinated fascicles of Goll and Burdach. There is an important delay in the increase in volume of axons particularly within the structures of late myelination. The importance of the lacking axonal growth in relation to myelination is discussed.
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  • 29
    ISSN: 1432-0533
    Keywords: Aseptic Meningitis ; Atheromatous Material ; Hypersensitivity ; Electron Microscopy ; Macrophages ; Pia-Arachnoid ; Granuloma
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 500 mg of sterile pooled human atheromatous material was injected into the cisterna magna of 6 mongrel dogs. Repeated cisternal punctures were done at various intervals until sacrifice from 1 day to 28 days following injection. CSF was obtained for cell count, sugar, protein and analysis in the Technicon 6/60 which measured 14 additional chemical and enzymatic variables. All 6 animals showed a prompt cerebrospinal fluid (CSF) pleocytosis which largely subsided during the first 2 weeks after injection. Increased CSF protein content developed more slowly, but was more prolonged than the pleocytosis. There was a variable decrease in CSF sugar and increase in CSF lactate dehydrogenase, calcium and inorganic phosphorous. Light and electron microscopic studies showed an intense acute inflammatory reaction with marked phagocytosis of the foregin material, probably by arachnoidal cells and moderate edematous changes in the astrocytic processes at the site of injection. During the first 2 weeks after the injection the inflammatory reaction became chronic and the edematous changes in the medulla subsided.
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  • 30
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    Acta neuropathologica 30 (1974), S. 175-181 
    ISSN: 1432-0533
    Keywords: Reacting Astrocytes ; Phagocytosis ; Experimental Gliomas ; Ethylnitrosourea ; Electron Microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The fine structure of reacting astrocytes in experimental gliomas has been described. These tumours were induced transplacentally by 30 mg of N-ethyl-N-nitrosourea per kg of body weight injected into the tail vein of pregnant BD-IX rats on the 15th day of gestation. In tumour-bearing animals astrocytes undergo striking morphological changes and show increased mitotic activity. Reacting astrocytes around gliomas display large, eccentric, irregular nuclei and the abundant cytoplasm contains an increased number of cell organelles. The most dramatic increase is in glial filaments: these form thick bundles at the periphery of the cells and in the processes which are frequently seen around demyelinated axons. Reacting astrocytes engulf and break down myelin sheaths: their remnants, lamellar inclusion bodies and lipid droplets, are present in the cytoplasm. Extravasated erythrocytes are also surrounded by and digested in reacting astrocytes. Numerous lysosomes could provide the necessary enzymes for the phagocytic activity of these cells.
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  • 31
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    Acta neuropathologica 30 (1974), S. 155-173 
    ISSN: 1432-0533
    Keywords: GM1-Gangliosidosis ; Glycoproteins ; β-Galactosidase ; Lysosomal Disease ; Electron Microscopy ; Genetics of GM1-Gangliosidosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Post-mortem studies on a 6-year old boy with GM1-gangliosidosis, Type II revealed no evidence of accumulation of residual bodies nor of gangliosides or glycoproteins in liver and spleen. In brain tissue the ganglioside GM1 accounted for 70% of the ganglioside fraction and ganglioside-NANA was increased 3.6 fold over controls. In addition, the brain tissue contained large amounts of glycoprotein, glycoprotein derived galactose being increased 2.5 times. The neuronal accumulation of tertiary lysosomes exhibited a characteristic distributional pattern: in general the large neuronal perikarya were more consistently involved with the exception of the motor cells of the cranial nerve nuclei, III, IV, and VI. In addition to characteristic MCB's, the nerve cells contained residual bodies with a granulo-floccular matrix, presumed to represent glycoproteins. The distribution of the mutant gene was studied among 30 blood relatives of the proband at risk and 6 carriers could be ascertained on the basis of a reduced leukocytic β-galactosidase activity. The partly purified enzyme from the patient's liver revealed 20% activity as compared to that of normal controls. All three fractions obtained by DEAE cellulose column chromatography exhibited markedly reduced activity at pH 3.6, but nearly normal activity at pH 6.6. The reduced activity corresponded to the B component of the enzyme as shown by electrophoretic separation. It is pointed out that this case cannot be diagnosed as “generalized gangliosidosis” for the process of ganglioside accumulation was restricted to nervous tissue.
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  • 32
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    Acta neuropathologica 30 (1974), S. 189-196 
    ISSN: 1432-0533
    Keywords: Lafore Bodies ; Polysaccharidosis ; Electron Microscopy ; Epilepsia ; Histochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Cerebral biopsies of three patients aged 22, 18 and 16 years with myoclonic epilepsy contained Lafory bodies. Two were a brother and sister of consanguineous parents. The Lafora bodies occurred in most neurons but not in glial cells. The ultrastructure of these bodies showed a fibrillar and granular material in the perikaryon and neuropile. In some neurons small Lafora bodies were delimited by a double membrane, suggesting that in early phases they have a membrene which disappears when they become more developed. Other non-specific neuron alterations are described. One of the cases presented in the liver PAS positive bodies of a structure different from the Lafora bodies.
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  • 33
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    Acta neuropathologica 28 (1974), S. 93-103 
    ISSN: 1432-0533
    Keywords: Hexachlorophene Intoxication ; Toxic Encephalopathy ; Optic Nerve Necrosis ; Cerebral Edema ; Status Spongiosus ; Electron Microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary This is the first report of neuropathologic findings following oral ingestion of hexachlorophene in the human. The patient was a 7 year old boy who accidentally ingested 45 ml (approx.) of pHisoHex (hexachlorophene).Toxic reactions included nausea, vomiting, anorexia, diarrhea, decrease in visual acuity, blurred vision blindness, somnolence and disorientation. He developed cardiac arrhythmia, fever, isoelectric EEG and finally respiratory and cardiac arrest 61 h after admission. Autopsy findings showed interstitial myocarditis, pneumonitis and acute bronchiolitis. The brain was edematous. Light microscopy revealed mild diffuse vacuolization of white matter, occasional neuronal degeneration, most prominent on deepest layers of the visual cortex. Disintegration of myelin sheaths and necrosis of axon cylinders were present throughoutoptic pathways. Electron microscopy revealed large, empty extracellular and intramyelinic spaces formed by splitting and separation of the myelin lamellae. These changes are known to occur in experimental animals intoxicated with hexachlorophene, triethyltin, isonicotinic acid hydrazide and cuprizone. However, with respect to hexachlorophene, the localization of lesions to be optic pathways appears to be dependent upon an oral route of administration.
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  • 34
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    Acta neuropathologica 27 (1974), S. 1-10 
    ISSN: 1432-0533
    Keywords: Leprosy ; Lepromatous ; Axonal Bacillation ; Schwann Cells ; Electron Microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary M. leprae bacilli in nerves of 3 patients with lepromatous leprosy were found in the axoplasm of myelinated and unmyelinated nerve fibers. Axonal bacillation occurred in as much as 2% of myelinated axons. Bacilli within Schwann cells were a more common finding in lepromatous leprosy that intra-axonal bacilli. Intra-axonal bacillation probably represents a late stage phenomenon in lepromatous leprosy. Intra-axonal bacilli may contribute to the dissemination of leprosy by migration of bacilli within the axon, and may contribute directly to nerve fiber destruction.
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  • 35
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    Acta neuropathologica 27 (1974), S. 69-82 
    ISSN: 1432-0533
    Keywords: Chronic Nerve Compression ; Median Nerve ; Guinea-Pig ; Electron Microscopy ; Degeneration ; Regeneration
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In guinea-pigs with chronic median nerve compression at the wrist the electron microscopic changes at level of the lesion and both proximal and distal to it have been studied. At the level of the lesion in animals with prolonged motor latency there was a loss of large myelinated fibres. Remaining large fibres had disproportionately thin myelin sheaths or were demyelinated. Regenerating clusters containing myelinated fibres were present. Evidence of degeneration and regeneration of unmyelinated fibres was present in the more severely affected nerves of this group. Distal to the wrist myelinated fibre density recovered, with regenerating clusters and many axons having disproportionately thin myelin sheaths. Midforearm and upper arm levels were normal. In nerves in which no muscle response to electrical stimulation could be recorded in the palm, a few fibres devoid of myelin remained at the wrist. Immediately proximal to it myelinated fibres were rare, the main feature being Schwann cells containing axons devoid of myelin some of which were degenerating. Degeneration of myelinating fibres within regenerating clusters was seen. At the mid-forearm level large myelinated fibres were reduced and increased numbers of regenerating clusters were seen. Evidence of regeneration of unmyelinated fibres was found. The upper arm was normal.
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  • 36
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    Acta neuropathologica 27 (1974), S. 247-256 
    ISSN: 1432-0533
    Keywords: Werdnig-Hoffmann's Disease ; Electron Microscopy ; Muscle Biopsy ; Myotube-like Cells
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary An ultrastructural study was carried out on muscle biopsies of 7 children with Werdnig-Hoffmann's disease. The muscle fibres were classified into 3 categories: 1. Muscle cells of normal diameter without any distinct or only slight changes. 2. Small muscle cells with a large central nucleus with the appearance of myoblast at a later stage of development. 3. Cells resembling myotubes containing in a common basement membrane two to four cells at different stages of maturation. Myoblast and myotube-like cells seemed to resemble foetal muscle fibres. Such fibres appear to represent an arrest in maturation rather than muscle atrophy.
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  • 37
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    Cell & tissue research 150 (1974), S. 167-178 
    ISSN: 1432-0878
    Keywords: Pigment cell ; Red hair ; Sunburn ; Man ; Electron Microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Pigment cells of human red hair (pheomelanocytes) are never connected to keratinocytes by desmosomes or other defined cell junctions. In the dendritic processes of pheomelanocytes, thin filaments, about 50–80 Å in diameter, and microtubuli can be observed. Early prepheomelanosomes contain loosely arranged filaments. With the onset of pheomelanogenesis dense material is deposited on the filaments. Distinction between late prepheomelanosomes and pheomelanosomes is not clearly possible, because of the disorganized appearance of the content. Furthermore, the content of pheomelanosomes sometimes seems to be disintegrated. By means of the DOPA reaction, tyrosinase activity is shown to be present in: a) prepheomelanosomes, b) large cisternae apposed at one side of dictyosomes, c) small cisternae of the smooth endoplasmic reticulum, and d) coated and uncoated vesicles. The results suggest that red pigment granules are formed in a manner similar to that of melanin granules. It is further assumed that an inadequate stability of pheomelanoprotein accounts for the inability of red-haired people to develop effective protection against ultraviolet light.
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  • 38
    ISSN: 1434-4726
    Keywords: Spiral ganglion and Organ of Corti ; Electron Microscopy ; Influence of Different Fixatives and Fixation Methods
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Das Ganglion spirale und Cortische Organ des Meerschweinchens wurden nach Osmium- und kombinierter Glutaraldehyd-Osmiumfixation sowie Anwendung verschiedener Fixationsmethoden elektronenmikroskopisch untersucht. Die Strukturen des Cortischen Organs wurden hierbei nicht wesentlich beeinflußt. Am Ganglion spirale ergaben sich Unterschiede im Aufbau der Myelinhüllen der Ganglienzellen. Es wird diskutiert, daß es sich beim semikompakten Myelin um ein Artefakt der Osmiumfixation handelt und daß Glutaraldehyd den Aufbau der Myelinhüllen im Bereich der Spiralganglienzellen naturgetreuer wiedergibt als Osmium.
    Notes: Summary We have been examining with the electron microscope the spiral ganglion and the organ of corti in guinea pigs, using osmium and a combined glutaraldehyde-osmiumfixation together with various fixation techniques. The structures of the organ of corti were not considerably effected. Differences in the structure of the myelin sheets of ganglion cells were found in the spiral ganglion. Presumably the semicompact myelin represents an artefakt after osmium-fixation, glutaraldehyde being able to demonstrate clearer the structure of the myelin sheets on spiral ganglion cells compared to osmium.
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  • 39
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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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  • 40
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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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  • 41
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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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  • 42
    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.
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  • 43
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    Weinheim : Wiley-Blackwell
    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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  • 44
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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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  • 45
    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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  • 46
    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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  • 47
    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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  • 48
    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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  • 49
    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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  • 50
    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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  • 51
    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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  • 52
    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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  • 53
    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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  • 54
    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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  • 55
    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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  • 56
    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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  • 57
    Electronic Resource
    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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  • 58
    Electronic Resource
    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.
    Additional Material: 1 Ill.
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  • 59
    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.
    Additional Material: 2 Ill.
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  • 60
    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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  • 61
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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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  • 62
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    Weinheim : Wiley-Blackwell
    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.
    Additional Material: 2 Ill.
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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: 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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  • 64
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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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  • 65
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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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  • 66
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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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  • 67
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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.
    Additional Material: 1 Ill.
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  • 68
    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.
    Additional Material: 3 Ill.
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  • 69
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    Weinheim : Wiley-Blackwell
    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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  • 70
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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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  • 71
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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.
    Additional Material: 3 Ill.
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  • 72
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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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  • 73
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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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  • 74
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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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  • 75
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    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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  • 76
    Electronic Resource
    Electronic Resource
    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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  • 77
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    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.
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  • 78
    Electronic Resource
    Electronic Resource
    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.
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  • 79
    Electronic Resource
    Electronic Resource
    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.
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  • 80
    Electronic Resource
    Electronic Resource
    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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  • 81
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    Weinheim : Wiley-Blackwell
    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.
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  • 82
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    Electronic Resource
    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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  • 83
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    Weinheim : Wiley-Blackwell
    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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  • 84
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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.
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  • 85
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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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  • 86
    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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  • 87
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    Weinheim : Wiley-Blackwell
    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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  • 88
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    Weinheim : Wiley-Blackwell
    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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  • 89
    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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  • 90
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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.
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  • 91
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    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.
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  • 92
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    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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  • 93
    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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  • 94
    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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  • 95
    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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  • 96
    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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  • 97
    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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  • 98
    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.
    Additional Material: 4 Tab.
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  • 99
    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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  • 100
    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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