Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • 1990-1994
  • 1985-1989
  • 1970-1974  (176)
  • 1850-1859
  • 1972  (176)
  • Ultrastructure  (115)
  • Physical Chemistry  (61)
Source
Material
Years
  • 1990-1994
  • 1985-1989
  • 1970-1974  (176)
  • 1850-1859
Year
Keywords
  • 101
    Electronic Resource
    Electronic Resource
    The structure of the organ of bellonci of the syncarid crustacean, Anaspides tasmaniae (Thomson) (1972)
    Springer
    Cell & tissue research 132 (1972), S. 431-450 
    Details
    ISSN: 1432-0878
    Keywords: Organ of bellonci (Anaspides tasmaniae) ; Crustacea ; SPX organ ; Receptor ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The organ of Bellonci of Anaspides tasmaniae (Thomson) (Crustacea, Syncarida) is described light and electron microscopically, and a few histochemical tests are reported. Located ventrally in the eyestalk below the medulla interna, the organ is composed of a number of cavities. These are similar in structure in their contents and associated cellular components, which include two types of glia cells delimiting each cavity and the terminal parts of a few dendrites. Each dendrite usually bears two cilia, which project into the cavity where they split up into numerous branches. The organ is supplied by three nerve tracts: two from the medulla terminalis and one from the medulla interna. The sensory pore, which is innervated from the medulla interna, is not closely associated with the organ of Bellonci in Anaspides. No marked secretory activity is detectable by histochemical or ultrastructural observations. It is thought that the organ has a sensory function.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00306635
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 102
    Electronic Resource
    Electronic Resource
    The eyes of Creophilus erythrocephalus F. and Sartallus signatus sharp (Staphylinidae: Coleoptera) (1972)
    Springer
    Cell & tissue research 133 (1972), S. 59-86 
    Details
    ISSN: 1432-0878
    Keywords: Compound eyes ; Coleoptera ; Ultrastructure ; Dark-light-adaptation ; Irregularities
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The structures of the eyes of two Staphylinid beetles, one large (Creophilus erythrocephalus—18 mm in length) and one small (Sartallus signatus—3 mm in length), were compared. 1. The gross structure of the two eyes is the same: a) biconvex corneal lens, b) crystalline cone of “acone type”, c) narrow crystalline thread and thickening of cone cell extensions just above the rhabdom, d) seven retinula cells plus one basal cell, and e) almost the same corneal refractive index and optical properties of the corneal cuticle. Considerable differences exist in size, shape and arrangement of rhabdom, retinula cells and their axons. The smaller size of the eye of Sartallus is caused by reduction of number of facets rather than cell size, and, in fact, retinula cells and rhabdom have been found to be larger in the smaller beetle. 2. Structural changes during dark-light-adaptation affect crystalline cone, position of screening pigment and size of intercellular spaces between the retinula cells. In the dark-adapted state the cone retracts a little and the crystalline tract becomes wider. A thickening of cone cell extensions occurs just above the rhabdom. Screening pigment migrates to a more distal position and intercellular spaces between the retinula cells considerably increase in size as compared with the light-adapted eye. 3. Both eyes are rich in irregularities. An attempt to classify anomalies of compound eyes has been made. The number of cone cells and principal pigment cells varied, in some cases, from 1–5 and 0–3 respectively. Basal retinula cells did not always contribute to the rhabdom. 4. Interferometrical observations reveal the extreme optical homogeneity of the entire corneal cuticle of the eyes of both species. No layers of different refractive index or optical separation of adjacent ommatidia can be found. The refractive index of the cornea of Creophilus is 1.469; that of Sartallus is 1.488. 5. Functional consequences of the changes which occur during dark-light-adaptation are discussed. Exposure to intense light appears to cause a rapid aging of retinula cells, which is indicated by an increase of onion- and multivesicular bodies.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00307068
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 103
    Electronic Resource
    Electronic Resource
    Die Ultrastruktur des Gabeschen Organs von Schizophyllum sabulosum L. (Diplopoda, Iuliformia) (1972)
    Springer
    Cell & tissue research 132 (1972), S. 273-285 
    Details
    ISSN: 1432-0878
    Keywords: Diplopoda ; Organ of Gabe ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung 1. Das Gabesche Organ von Schizophyllum sabulosum ist paarig und liegt im seitlichen Clypeolabrum. Es wird von Axonen des Nervus labri medialis erreicht, der vorher Seitenzweige abgegeben hat. 2. Die Axone gehören neurosekretorischen Zellen des Protocerebrum an und enthalten Neurosekret. Die Elementargranula sind recht gleichmäßig ellipsoid, der große Durchmesser beträgt ca. 1200 Å. Die Axone enden im Organ und stellen dessen extrinsische Komponente dar. 3. Außerdem gibt es zwei intrinsische Zelltypen: 1) Drüsenparenchymzellen mit axonartigen Fortsätzen und 2) gliaartige Zellen. Die Parenchymzellen bilden Sekret in Form opaker Vakuolen, die deutlich größer als die Neurosekretgranula sind. Auffällig ist das überwiegend vesikuläre endoplasmatische Reticulum. Die Mitochondrien liegen in der Nähe von myelinähnlichen Körpern; ihre Außenmembran ist stellenweise vakuolig vorgewölbt. Die axonartigen Fortsätze enthalten viele längsorientierte Mikrotubuli. 4. Die langen Fortsätze der gliaartigen Zellen umhüllen die Parenchymzellen und die extrinsischen Axone meist in mehreren Schichten. Es gibt aber auch Bereiche, in denen vor allem die Fortsätze der Parenchymzellen und die extrinsischen Axone nackt sind. 5. Das Organ ist gegen das umgebende Hämocoel von einer dicken, lamellierten Stromahülle abgegrenzt. Auch Interzellularräume sind mit Stroma gefüllt. 6. Das Organ wird mit der Cerebraldrüse einiger Chilopoden und gewissen endokrinen Organen anderer Diplopoden und Insekten verglichen.
    Notes: Summary 1. The paired organ of Gabe of Schizophyllum sabulosum is situated in the lateral clypeolabrum. It is innervated by axons of the medial labral nerve, which divides in several branches before reaching the organ. 2. Axons extend from neurosecretory cells of the protocerebrum and contain neurosecretory droplets, which are almost ellipsoid and about 1,200 Å in diameter. The axons terminate in the organ and constitute its extrinsic elements. 3. In addition, there are two types of intrinsic cells: (1) parenchyma cells with axon-like processes and (2) glia-like cells. The parenchyma cells produce secretory material in the form of opaque vacuoles, which are clearly larger than the neurosecretory granules. The preponderantly vesicular endoplasmic reticulum is conspicuous. Also characteristic are the mitochondria, whose superficial membranes are expanded locally, and which lie in the near vicinity of myeline-like bodies. The axon-like processes contain many microtubuli oriented in longitudinal direction. 4. The slender processes of the glia-like cells envelop both parenchyma cells and extrinsic axons usually in several layers; but there are also regions in which the processes of the parenchyma cells and, above all, the extrinsic axons are naked. 5. The organ is delimited from the surrounding hemocoele by a thick laminated stroma. Intercellular spaces are also filled with stroma. 6. The organ is compared with the cerebral gland of some chilopods and with certain endocrine organs of other diplopods and insects.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00307017
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 104
    Electronic Resource
    Electronic Resource
    An ultrastructural study of the body wall muscles of the pentastomid Reighardia sternae dies. 1864 parasitic on the herring gull Larus argentatus pontopp (1972)
    Springer
    Cell & tissue research 130 (1972), S. 12-17 
    Details
    ISSN: 1432-0878
    Keywords: Muscle tissue ; Pentastomid ; Body wall ; Parasite ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The fine structure of the body wall muscle of the pentastomid Reighardia sternae is described. The muscle fibres are separated from one another and form two layers, circular and longitudinal. They are cross-striated with approximately 11 actin filaments surrounding each myosin filament. The T-system consists of simple in-pushings of the sarcolemma. The SR is also simple and forms both dyadic and triadic contacts with the T-system tubules and dyadic contacts with the sarcolemma. Electron-dense inclusions occur, usually in the vicinity of the Z-lines, and it is suggested that these may be composed of unsaturated lipids.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00306991
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 105
    Electronic Resource
    Electronic Resource
    Ultrastructure de l'endomètre humain normal (1972)
    Springer
    Cell & tissue research 133 (1972), S. 47-57 
    Details
    ISSN: 1432-0878
    Keywords: Endometrium ; Human ; Granular stroma cells ; Relaxin ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé L'ultrastructure générale des cellules K endométriales est semblable chez l'Homme, le Rat et le Singe. Mais les granulations des cellules K humaines sont plus variées que dans ces deux dernières espèces et ont certains aspects suggérant une fonction catabolique. Etant donné cet aspect catabolique et l'existence connue d'une activité phosphatasique acide de ces cellules contenant de la relaxine, les auteurs suggèrent que les cellules K pourraient être des cellules sécrétantes en involution et ques les cellules sécrétant activement la relaxine pourraient avoir un aspect morphologique quelque peu différent de celui des cellules K.
    Notes: Summary The general ultrastructure of endometrial granular stroma cells is similar in man, rat, and monkey. But the granulations of human granular stroma cells are more various than in these two last species and have some aspects suggesting a catabolic function. With respect to this catabolic aspect and the previously shown acid-phosphatase activity of these relaxin-containing cells the authors suggest that the granular stroma cells could be involutive secretory cells and that the active relaxin-secretory cells may have some different morphological aspect.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00307067
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 106
    Electronic Resource
    Electronic Resource
    Zur Morphologie des Ovars von Viviparus contectus (Millet 1813), (Gastropoda, Prosobranchia) (1972)
    Springer
    Cell & tissue research 133 (1972), S. 103-118 
    Details
    ISSN: 1432-0878
    Keywords: Ovary ; Gastropoda ; Follicle cells ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Das Ovar von Viviparus contectus besteht, wie licht- und elektronenmikroskopische Untersuchungen ergeben, aus einem langen, terminal verzweigten dünnen Schlauch, dessen Wand von einem Epithel aus Oocyten in allen Entwicklungsstadien und Follikelzellen gebildet wird. Das Vorkommen von Oogonien in den Ovarien adulter Weibchen ist zweifelhaft. Die Follikelzellen sind als Begleitzellen der Oocyten im allgemeinen extrem langgestreckt. Mit ihrer Basis sitzen sie einer dünnen Basalmembran fibrillärer Struktur auf, wie sie bisher nur für Mollusken beschrieben wurde. Die Follikelzellen enthalten große Mengen von Vesikeln, einen bemerkenswert gut ausgebildeten Golgi-Apparat, spärliches rauhes endoplasmatisches Retikulum und zahlreiche heterogene cytosomale Einschlüsse. Charakteristisch für die Zellen sind außerdem in der Längsrichtung liegende cytoplasmatische Mikrotubuli und vereinzelte Kinetosomen. Obwohl keine direkten morphologischen Beziehungen zwischen Follikelzellen und Oocyten festgestellt werden konnten, wird vermutet, daß die Follikelzellen Material degenerierender Oocyten aus dem Lumen des Ovars resorbieren und speichern. Dieses kann den heranwachsenden Oocyten zugute kommen.
    Notes: Summary The ovary of Viviparus contectus was studied light and electron microscopically. It consists of an extended and terminally branched duct, its wall being formed by oocytes of all stages and by follicle cells. The existence of oogonia in the adult females cannot be established with certainty. According to their relationship to the growing oocytes the follicle cells are in general extremely elongated. At the basis they are attached to a thin basement lamina having a fibrillar structure hitherto only known in molluscs. The follicle cells contain many vesicles, a remarkably well-developed golgi apparatus, some rough endoplasmic reticulum, and many heterogeneous cytosomes. Characteristic for these cells are also cytoplasmic microtubules oriented longitudinally along the cell axis. Kinetosomes can rarely be seen. Although there are no apparent direct interrelationships between follicle cells and oocytes, it is suggested that they are engaged in resorbing material of degenerating oocytes from the lumen of the ovary and in storing materials which may be used by the growing oocytes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00307070
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 107
    Electronic Resource
    Electronic Resource
    The ultrastructure of neuromuscular systems in Notoplana acticola, a free-living polyclad flatworm (1972)
    Springer
    Cell & tissue research 133 (1972), S. 277-288 
    Details
    ISSN: 1432-0878
    Keywords: Flatworm ; Muscle ; Neuromuscular junction ; Sarcoplasm ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Neuromuscular junctions in the marine polyclad flatworm, Notoplana acticola were studied with the electron microscope. Synapses were found between nerve endings and specialized extensions of the muscle cells. Characteristically these processes contained clear cytoplasm with a basal mitochondrion and numerous microtubules aligned parallel to the long axis of the extension. Sarcoplasmic diverticuli which contained the nucleus had granular cytoplasm with an assortment of membranes and organelles. We have proposed the term sarconeural junction to describe synapses between long sarcoplasmic extensions and nerve cells in flatworms as well as other animals. Tight junctions between adjacent contractile portions of muscle cells were common. As groups of cells appeared to be connected by tight junctions or shared common nerve terminals we conjectured that these formed discrete functional motor-units.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00307148
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 108
    Electronic Resource
    Electronic Resource
    Ultrastruktur und Jodaufnahme der Schilddrüse bei Larven des Krallenfrosches (Xenopus laevis Daud.) (1972)
    Springer
    Cell & tissue research 130 (1972), S. 553-574 
    Details
    ISSN: 1432-0878
    Keywords: Thyroid gland ; Xenopus laevis ; Iodine uptake ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Ziel dieser Untersuchung war eine physiologische Deutung der Ultrastruktur von Schilddrüsenepithelzellen bei Larven von Xenopus laevis. Dazu wurden elektronenmikroskopische Bilder mit morphometrischen Methoden quantitativ ausgewertet und die Ergebnisse mit Jodaufnahmedaten verglichen. So konnte die Aktivierung der Schilddrüse durch TSH bei kälteblockierten bzw. hypophysektomierten Tieren mit Veränderungen während der spontanen Metamorphose verglichen werden. Ihrer Ultrastruktur nach sind die Schilddrüsen blockierter Prometamorphoselarven in der Entwicklung auf ein früheres Stadium zurückversetzt. Auch zeigen hypophysektomierte Larven keine spontane Jodaufnahme. Eine einmalige TSH-Injektion läßt dann die Größe und Form der verschiedenen Organellen vorübergehend den Zustand der Kontrollen erreichen. Besonders rasch und stark sprechen einerseits die Kernstruktur, andererseits Mikrovilli und Kolloidtropfenvolumen, welche die Resorption von Thyreoglobulin charakterisieren, auf den TSH-Reiz an. Die Jodaufnahme verläuft langsamer. Auch reagieren die an der Synthese beteiligten Organellen später und schwächer. In der spontanen Metamorphose wachsen die Schilddrüsen, nach Totalvolumen, Cytoplasmavolumen einzelner Zellen und Epithelhöhe beurteilt, bis zum Ende der Metamorphose weiter und nehmen entsprechend mehr Jod auf. Ebenso wird während der ganzen Klimax die Kolloidresorption der einzelnen Zellen stärker. Aus den Ergebnissen wird geschlossen, daß die TSH-Sekretion schon in der Prometamorphose einsetzt und bis gegen Ende der Metamorphose zunimmt.
    Notes: Summary The epithelial cells of the thyroid gland in larvae of Xenopus laevis were investigated with the electron microscope. Morphometrical methods yielded quantitative data on the morphology. The uptake of radioactive iodine was studied in order to obtain information on the physiological activity. Thus changes in the thyroid gland following the injection of TSH in tadpoles which had been hypophysectomized or blocked at low temperature were compared with the development of glands during spontaneous metamorphosis. The thyroid glands of blocked prometamorphic larvae resemble those of younger developmental stages as judged by their ultrastructure. In addition no spontaneous accumulation of iodine is observed. Following an injection of TSH the morphology of the various organelles becomes temporarily identical to that of the controls. These changes are most prominent in the nucleus as well as in the microvilli and the colloid droplets, which characterize the resorption of thyroglobulin. Only a minor effect of the TSH stimulus is found on iodine uptake and on organelles concerned with protein synthesis. During normal metamorphosis an increase is observed in the following parameters: (1) volume of the thyroid gland, (2) volume of the cytoplasm and height of single epithelial cells, (3) resorption of colloid, (4) iodine uptake. This increase persists until the end of the climax. Based on the present results TSH secretion is assumed to start in early prometamorphosis and to rise up to the end of metamorphosis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00307007
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 109
    Electronic Resource
    Electronic Resource
    Zur Morphologie und Funktion der Calcitoninzellen (C-Zellen) der Ratte (1972)
    Springer
    Cell & tissue research 134 (1972), S. 13-30 
    Details
    ISSN: 1432-0878
    Keywords: Rat ; Thyroid C-cells ; Ultrastructure ; Tocopherol and Ubiquinone deficiency ; Substitution (d,1-α-Tocopherol, α-Tocopherolquinone)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung An der Schilddrüse von Wistar-Ratten wurde der Einfluß der Kost (Laborstandardkost, halbsynthetische-tocopherolhaltige und halbsynthetische-tocopherol-freie Kost) und der subkutanen Injektion von Tocopherol und Tocopherolchinon auf die Ultrastruktur der C-Zellen untersucht. Während nach Standardfütterung die Aktivität der C-Zellen der Norm entspricht, werden Syntheseleistung und Sekretabgabe dieser Zellelemente durch die halbsynthetische-tocopherolhaltige Kost gesteigert und im alimentären Tocopherol-Ubichinonmangel wieder gedämpft. Der elektronenmikroskopisch erkennbare Gehalt der C-Zellen an Sekretgranula entspricht der in vitro ermittelten Calcitoninaktivität. Die Beziehungen zwischen den Funktionskreisen von Thyreozyten und Calcitoninzellen werden diskutiert.
    Notes: Summary The influence of different diets (standard laboratory diet, semisynthetic tocopherol-containing and semisynthetic tocopherol-free diet) and the influence of subcutaneous injections of tocopherol and tocopherolquinone upon the ultrastructure of the C-cells in the thyroid gland of Wistar rats were investigated. While the activity of the C-cells is quite normal after feeding a standard diet, the synthetic and secretory activities of these cells show an increase with a semisynthetic diet containing tocopherol, but a decrease during alimentary lack of tocopherol and tocopherolquinone. The amount of secretory granules in the C-cells as seen with the electron microscope corresponds with the in vitro-activity of extracted calcitonin. The relations between the functional system of the thyrocytes and that of the C-cells are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00307233
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 110
    Electronic Resource
    Electronic Resource
    The ultrastructure of the A1 sensilla on the posterior surface of the clypeo-labrum of Locusta migratoria migratorioides (R and F) (1972)
    Springer
    Cell & tissue research 134 (1972), S. 539-554 
    Details
    ISSN: 1432-0878
    Keywords: Chemoreceptors ; Locusta ; Clypeo-labrum ; Light and electron microscopy ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The A1 sensilla are asymmetric in distribution. Each sensillum contains five bipolar neurons, the distal regions of which extend to the tip of a cuticular cone which has a terminal pore. This was shown with the scanning electron microscope, but was not seen in section. The receptor-lymph cavity of the tormogen cell and the basal cavity of the neurilemma cell contain an electron-dense material unlike other contact chemoreceptors of Locusta prepared for electron microscopy in the same manner. Isolated axons of unknown function occur below the basement membrane and also between epidermal cells surrounding the sensillum.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00307673
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 111
    Electronic Resource
    Electronic Resource
    Ultrastructure of the anuran pars intermedia following severance of hypothalamic connection (1972)
    Springer
    Cell & tissue research 131 (1972), S. 545-557 
    Details
    ISSN: 1432-0878
    Keywords: Pars intermedia ; Hypothalamus ; Anurans ; Hormone release ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ultrastructure of the pars intermedia of Rana catesbeiana tadpoles was studied following isolation from the hypothalamus, in vivo after sectioning of the pituitary stalk, and in vitro after implantation of the pituitary into a piece of tail fin. Both experimental procedures were followed by rapid and sustained skin darkening. Pituitaries from normal light and dark adapted tadpoles served as controls. In 4-hour disinhibited glands, melanotrophs revealed hyperactive Golgi bodies, colloid vesicles (1–2 microns) in close proximity to axon terminals, and no apparent loss of secretory granules. At 24 hours extracellular colloid adjacent to axon terminals was found, and extensive arrays of RER appeared in the melanotrophs. Obvious granule loss from secretory cells occurred within a week, by which time the cytoplasm was occupied by large cisterns of SER and RER and abundant free ribosomes. Dense core vesicles (600–900 Å) in aminergic nerve terminals disappeared shortly after isolation of the pituitary from the hypothalamus, and only decreasing numbers of translucent vesicles (200–300 Å) were found. The functional significance of these changes is discussed, with particular emphasis on the mode of acute hormone release.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00306970
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 112
    Electronic Resource
    Electronic Resource
    Oligodendrocytes in the normal and chronically de-afferented lateral geniculate body of the monkey (1972)
    Springer
    Cell & tissue research 135 (1972), S. 115-127 
    Details
    ISSN: 1432-0878
    Keywords: Oligodendroglia ; Monkey ; De-afferentation ; Ultrastructure ; Densebodies
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Electron microscopical examination of the norma and de-afferented ‘laterall geniculate body’ of the monkey following paraformaldehyde-glutaraldehyde vascular perfusion revealed distinctive morphological features of different types of oligodendrocyte. These cells were normally situated as perineuronal satellites or in relation to axons and capillaries. A wide range of nuclear and cytoplasmic densities were displayed by both satellite and interfascicular oligodendrocytes. The following distinctive features for the identification of ligodendrocytes were utilised: the presence of large quantities of free ribosomes and ribosomal rosettes, microtubular profiles, dense marginal aggregation of nuclear chromatin together with light patches and numerous nuclear pores; but the absence of broad cytoplasmic processes, glycogen and gliofibrils. Circumferential perinuclear organization of the cytoplasmic organelles was typical of oligodendrocytes. Particular attention was paid to perineuronal satellite cells in view of the known transneuronal atrophy in the de-afferented geniculate body. Some cells having a nuclear pattern of oligodendrocytes but showing hyalinisation of perikaryon were seen in de-afferented laminae. A notable feature was the presence of variegated “osmiophilic bodies” in the perikaryon of oligodendrocytes also situated in the de-afferented laminae. A cell type combining the features of oligodendrocytes and astrocytes was classified as ‘intermediate neuroglia’.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00307092
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 113
    Electronic Resource
    Electronic Resource
    Les cellules corticotropes de l'hypophyse d'un Amphibien après interrénalectomie (1972)
    Springer
    Cell & tissue research 132 (1972), S. 333-364 
    Details
    ISSN: 1432-0878
    Keywords: Pituitary gland ; Amphibians ; Corticotrophs ; Ultrastructure ; Immunocytochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé L'identification des cellules responsables de l'élaboration de la corticotropine (ACTH) a été envisagée chezRana esculenta. Les effects causés par l'interrénalectomie au niveau de l'hypophyse ont été étudiés parallèlement par immunofluorescence et au microscope électronique. Au microscope à fluorescence, les cellules détectées chez les animaux témoins avec un antisérum anti-synachten1 bordent en grand nombre les capillaires des zones médiorostrale et ventrale du lobe antérieur. Deux jours après interrénalectomie, le nombre de cellules fluorescentes décroît, douze jours après l'intervention, il ne subsiste pas d'éléments fluorescents dans cette zone. Au microscope électronique, les cellules corticotropes présentent de fines granulations d'environ 200 mμ de diamètre. Après interrénalectomie bilatérale, ces cellules sont fortement stimulées, elles sont sujettes à d'importantes modifications morphologiques; l'aspect morphologique des autres catégories de cellules antéhypophysaires, par contre, n'est pratiquement pas modifié. Douze jours après l'opération, la plupart de ces cellules sont dégranulées, l'ergastoplasme et l'appareil de Golgi sont bien développés. Ces observations suggèrent que les cellules péricapillaires de la moitié rostrale de lapars distalis sécrètent l'hormone corticotrope.
    Notes: Summary Identification of the cell types responsible for the production of adrenocorticotropin (ACTH) was performed inRana esculenta. The effects of interrenalectomy on the pituitary cells were studied as well by immunofluorescence, as by electron microscopy. In control animals, the ACTH cells studied by immunofluorescence are numerous around the blood vessels of the medio-rostral and medio-ventral part of the anterior lobe. Two days after interrenalectomy the number of fluorescent cells decreases. Twelve days after, the operation all the fluorescent cells disappeared. The fine structure of the corticotrophs is characterized by the presence of small secretory granules (200 mμ). After bilateral interrenalectomy this cell type is markedly stimulated; it displays striking morphological changes, while the morphology of the other pituitary cell types is not considerably modified. Twelve days after operation most of these cells are degranulated, the rough endoplasmic reticulum and the Golgi apparatus are well developed. These findings suggest that the pericapillary cells of the rostral half of thepars distalis produce the adrenocorticotrophic hormone.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02450713
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 114
    Electronic Resource
    Electronic Resource
    Ultrastruktur des Pseudoculus vonEosentomon (Protura, Insecta) (1972)
    Springer
    Cell & tissue research 135 (1972), S. 539-551 
    Details
    ISSN: 1432-0878
    Keywords: Pseudoculus ; Eosentomon (Protura, Insecta) ; Sense organ ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung In der Feinstruktur unterscheidet sich der Pseudoculus vonEosentomon nicht wesentlich von dem der Acerentomiden. Durch einen Endokutikulaporus treten die dendritischen Fortsätze zweier Sinneszellen, jeweils umgeben von einer Hüllzelle, in den Außenraum des Pseudoculus ein. Der Außenraum wird nach distal von einer äußeren Kutikulaschicht — vermutlich Epikutikula — abgeschlossen. Sie vermittelt durch regelmäßig angeordnete lange Spalten die Verbindung zur Außenwelt. Am Grunde der Spalten finden sich Porentubuli, die mit den Hüllzellen oder den distalen Fortsätzen der Dendriten Kontakt haben können. Aus der Feinstruktur kann geschlossen werden, daß der Pseudoculus als Chemo-, Hygro- und/oder Thermorezeptor fungiert.
    Notes: Summary Concerning its fine structure the pseudoculus of Eosentomon is quite similar to that of Acerentomide Protura. There are two sensory cells innervating the organ. From each of them one dendritic process derives, surrounded by one enveloping cell. The processes of these four cells enter the distal cavity of the pseudoculus through a pore in the endocuticular layer. The cuticular layer of the cap seems to consist of epicuticle only. It is furrowed by long clefts connecting the distal cavity of the organ with the outside. Poretubules insert at the base of the clefts and may have contact with the cell membranes of both enveloping cells and dendritic processes. According to its structure the pseudoculus may function as chemo-, hygro- and/or thermoreceptor.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00583435
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 115
    Electronic Resource
    Electronic Resource
    Nervous system of the snailHelix aspersa (1972)
    Springer
    Cell & tissue research 135 (1972), S. 473-482 
    Details
    ISSN: 1432-0878
    Keywords: Neurosecretory nerves ; Glial and pigment cells ; Neural sheath ; Gastropods ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The fine structure of neurosecretory nerves and endings associated with the sheath of the infraesophageal ganglion ofHelix aspersa is described. The sheath is a neurohemal organ whose vascularized stroma receives both monoaminergic and peptidergic endings. The latter occur along the surface of the nerves or scattered within the stroma. They include a complex population of vesicular profiles. The granular vesicles (1300–3000 Å in diameter) exhibit structural modifications that may be related to the intra-axonal release of their neurohormones. The agranular vesicles (500–2000 Å in diameter) occur in large numbers and lie mostly adjacent to the axon surface. Synaptoid specializations seem to represent active sites for the extracellular discharge of neurosecretory material. The monoaminergic endings so far studied lack synaptoid specializations and contain small granular (800–1300 Å in diameter) and agranular (700 Å in diameter) vesicles. Two kinds of non-neural cells are associated with the nerves: glial cells and melanocytes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00583431
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 116
    Electronic Resource
    Electronic Resource
    Masthead (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972) 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040101
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 117
    Electronic Resource
    Electronic Resource
    Iron (II) and iron (III) isotope exchange in water-dimethyl sulfoxide mixturesAbstracted in part from the Ph.D. Thesis of Marian S. Henry, University of Minnesota, December 1970. (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 37-48 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The rate of the isotope exchange reaction between iron(II) and iron(III) perchlorates has been measured in a solvent mixture containing a 3:2 mole ratio of water to dimethyl sulfoxide over the temperature range from 25° to -98°C. In this temperature range, the reactants can diffuse together faster than they can undergo isotope exchange. The activation enthalpy and entropy for the acid-independent reaction were 6.0 ± 1.2 kcal/mole and -38 ± 17 cal/deg mole, respectively. Below -22°C, the acid-dependent exchange reaction did not contribute significantly to the exchange. In liquid media at -112° and -117°C and in a solid glass at -136°C, no isotope exchange was observed over the period of a calculated half-life for the reaction. At these temperatures, the rate at which the reactants diffuse together is slower than the calculated rate of isotope exchange. In a solid glass at -196°C, no isotope exchange was observed over the period of one week.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040103
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 118
    Electronic Resource
    Electronic Resource
    Reaction of H and D atoms with deuterated propylenes (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 307-314 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Effects of deuterium substitution in propylene on the relative rates of H(D) atom abstraction from and addition to the olefin, and on the orientation of H(D) atom addition, have been studied in the gas phase at room temperature. Effects of isotopic substitution of the olefinic hydrogen atoms on abstraction could not be observed, but abstraction is reduced five- to tenfold by deuteration of the methyl group. Deuteration of either olefinic position enhances the rate of addition to the substituted carbon atom. Disproportionation-combination ratios for deuterium-substituted propyl radicals are not greatly different from those for unsubstituted radicals, the largest effect being for C3D7 radicals, for which the overall kd/kc is reduced 10-15%.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040307
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 119
    Electronic Resource
    Electronic Resource
    Abstraction by hydrogen atoms from ethylene, propylene, butene-1, and cis- and trans-butene-2 (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 315-324 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The position of abstraction by H atoms from ethylene, propylene, butene-1, and cis- and trans-butene-2 and the rates of abstraction relative to addition have been measured at 25°C. Only allylic abstraction was observed. From ethylene, abstraction relative to addition was ≤3×10-4. For propylene, butene-1, cis-butene-2, and trans-butene-2, abstraction occurred on 0.2%, 1.6%, 1.5%, and 0.9% of the reactive encounters, if dis-proprotionation-combination ratios for allyl and alkyl radicals are similar to those for alkyl-alkyl pairs.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040308
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 120
    Electronic Resource
    Electronic Resource
    Vibrational excitation of deuterium fluoride and hydrogen fluoride by atomic and diatomic species (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 293-306 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The vibrational excitation of HF and DF and the energy transfer efficiencies for various collision partners were investigated over the temperature and pressure ranges of 1400°K to 4100°K and 0.1 to 0.3 atm, respectively. The extent of excitation was determined as a function of time by continuously monitoring the infrared emission intensity at the center of the 1-0 vibration-rotation band of the molecule. Collisional efficiencies of HF, N2, O2, F, Cl, and DF in relaxing HF and of DF, HF, and N2 in relaxing DF are reported. A comparison with relaxation data for pure HF taken at lower temperature suggests that long-range attractive forces are mechanistically of major importance in the relaxation process. The relatively high efficiency of atomic chlorine in relaxing HF, i.e., (τP)HF-HF/(τP)HF-C1 ≥ 5 at 3000°K is discussed in terms of our previous result for atomic fluorine, i.e., (τP)HF-HF/(τP)HF-F = 18.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040306
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 121
    Electronic Resource
    Electronic Resource
    Secondary hydrogen isotope effect for the transition from olefin to free radical (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 325-330 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Secondary kinetic isotope effects occur in radical additions to deuterated olefins. Substitution of a deuterium at a carbon undergoing an sp2 to sp3 hybridization-change during reaction, Cβ in eq. (1), leads to an inverse isotope effect of 3-5% (kH/kD = 0.95-0.97). The effect at a carbon going from an olefinic to a radical center, Cα in eq. (1), generally has been assumed to be negligible, since a nominal sp2 hybridization is maintained throughout reaction. Using new, sensitive instrumentation for radioactivity determination and a recently developed quench correction technique, we now find that there is a small, normal isotope effect (kH/kT 1) associated with a change from olefin to radical. Specifically, when R· is the polystyryl radical, X is phenyl, and the α-C bears a tritium, kH/kT = 1.04. This result is discussed in relation to recent data on cycloaddition reactions.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040309
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 122
    Electronic Resource
    Electronic Resource
    Radical reactions of highly polar molecules. Chlorination of halopropanes (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 331-338 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: In polychloro-2,2-difluoropropanes, where a large inductive effect results in relatively low reactivity to chlorination, the presence of additional chlorine causes an increased reactivity of the hydrogens geminal to the chlorine and a reduced reactivity of the remote (third carbon) hydrogens. The ways in which resonance, inductive effect, and steric crowding interact in the rates of chlorination of polar molecules are discussed.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040310
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 123
    Electronic Resource
    Electronic Resource
    Carbon-nitrogen bond dissociation energy values in C-nitrosocompounds (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 339-343 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Measurements of the D(R—NO) bond strength in some C-nitrosocompounds have been made using an electron impact method. The appearance potential of the radical ion (R+) has been determined, the D(R—NO) bond energy being obtained from the relation \documentclass{article}\pagestyle{empty}\begin{document}$$D{\rm (R} - {\rm NO) = }AP{\rm (R}^{\rm + } {\rm)} - IP({\rm R}.)$$\end{document} The values obtained are: D(C6H5—NO) = 41 kcal/mole, D(t-C4H9—NO) = 34 kcal/mole, D(t-C5H11—NO) = 36 kcal/mole and D(i-C3H7—NO) = 36.5 kcal/mole. These values are in good agreement with the numerous estimations of Benson and coworkers and confirm that the C—N bond strength in C-nitrosocompounds is very much less than in nitrocompounds or in amines.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040311
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 124
    Electronic Resource
    Electronic Resource
    Computational modeling of the mechanisms of the free radical-chain reaction of alkanes with oxygen. The oxidation of isobutane, n-butane, and isopentane (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 345-362 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A general computational method for obtaining complete solutions of time-dependent kinetic equations has been developed and applied to free radical-initiated reactions of alkanes with oxygen. The method has been applied to the low-temperature, peroxide-initiated oxidations of isobutane and isopentane. Using available independently measured and estimated values for the rate constants and activation parameters for each of the 20 proposed reaction steps for the oxidation of isobutane, the rates and products have been calculated for both the liquid phase and gas phase in the range of 100°-155°C. The calculated rates and products of oxidation agree with published experimental values. The oxidation of isopentane was examined by a 32-reaction model. The rate constants were estimated using values for the appropriate rate steps in the oxidation of n-butane and isobutane. The calculation of the oxidation rate and products agree with our experiments.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040312
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 125
    Electronic Resource
    Electronic Resource
    Very low-pressure pyrolysis: VI. The decomposition of ethyl acetateThis work was supported in part by the Environmental Protection Agency Grant AP 00353-07, Air Pollution Control Administration. (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 265-271 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The pyrolysis of ethyl acetate has been studied by the very low-pressure pyrolysis (VLPP) technique. The results obtained agree well with the previously determined high-pressure Arrhenius parameters where log k∞ = 12.6 - 48.0/θ. The rate constants given by these parameters have also been shown to be consistent with the predictions of the RRK and RRKM theories and demonstrate the applicability of the technique to the study of thermal decompositions.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040303
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 126
    Electronic Resource
    Electronic Resource
    The second limit of hydrogen + carbon monoxide + oxygen mixtures (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 277-292 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Previous studies by Buckler and Norrish of the second limit of CO and O2 mixtures containing small amounts (0.25-10%) of H2 have been used to obtain the velocity constant of the reaction \documentclass{article}\pagestyle{empty}\begin{document}$${\rm O} + {\rm CO} + {\rm M = CO}_{\rm 2} + {\rm M}$$\end{document} These estimates of k33 = 3.9 × 108 and 3.5 × 108 liter2 mole-2 sec-1 (M = H2) at 500° and 560°C, respectively, have been combined with other estimates over the range 300°-3500°K to give k33 = 3.0 × 108 exp (-3000/RT) for M = Ar; the considerable scatter in the available points does not encourage any great confidence in this expression and may be attributed at least partly to the different molecules used as M by different workers. For KCl-coated and CsCl-coated vessels at 540°C, studies of the second limit of H2 + O2 mixtures, to which CO has been added, have indicated that with both the surfaces, the effect of CO on the limit is masked by changes in the surface nature. In the case of CsCl, the results have enabled a lower limit of about 0.6 to be obtained for the efficiency of CO relative to H2 in the reaction \documentclass{article}\pagestyle{empty}\begin{document}$${\rm H} + {\rm O}_{\rm 2} + {\rm M = HO}_{\rm 2} + {\rm M}$$\end{document} Use of a computer treatment to interpret the second limit of CO + H2 + O2 mixtures in aged boric-acid-coated vessels at 500°C gives a value of mCO = 0.74 ± 0.04 together with an estimate of k32 (H + CO + M″ = HCO + M″)/k4 = 0.022 ± 0.003, which leads to k32 = 2.3 × 108 liter2 mole-2 sec-1 (M = H2) at 500°C.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040305
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 127
    Electronic Resource
    Electronic Resource
    A flash photolysis-resonance fluorescence kinetics study of ground-state sulfur atoms: I. Absolute rate parameters for reaction of S(3P) with O2(3Σ). (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 367-382 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The flash photolysis-resonance fluorescence technique has been used to measure the reaction of ground-state sulfur atoms with molecular oxygen as a function of both temperature and total pressure. The most suitable source of S(3P) for this study was found to be COS in the presence of CO2, as a diluent gas and with the photolysis flash filtered so as to remove all radiation of wavelengths below 1650 Å. Under these conditions, it was found that over the temperature range of 252-423°K the rate data could be fit to a simple Arrhenius-type equation of the form \documentclass{article}\pagestyle{empty}\begin{document}$$k_1 = (2.24 \pm 0.27) \times 10^{ - 12} {\rm exp}\left({\frac{{{\rm - 0}{\rm .00} \pm {\rm 0}{\rm .10 kcal/mole}}}{{RT}}} \right)$$\end{document} Units are cm3 molec-1 s-1. The small A-factor for this reaction, the lack of any pressure dependence, and the direct observation of the production of O(3P) with increasing reaction time suggest that the S(3P) atom attacks the O2(3Σ) molecule end-on forming SOO which rapidly falls apart to form SO (3Σ) and O(3P).
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040402
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 128
    Electronic Resource
    Electronic Resource
    The reaction of O(1D) with CH4 (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 417-432 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The room-temperature photolysis of N2O (10-100 torr) at 2139 Å to produce O(1D) has been studied in the presence of CH4 (10-891 torr). The reactions of O(1D) with CH4 were found to be \documentclass{article}\pagestyle{empty}\begin{document}$$\begin{array}{*{20}c} {(4)} & {{\rm O(}^{\rm 1} D{\rm)} + {\rm CH}_{\rm 4} } & \to & {{\rm HO + CH}_{\rm 3} } & {0.95 \pm 0.05} \\ {(8)} & {} & \to & {{\rm O(}^{\rm 3} P{\rm)} + {\rm CH}_{\rm 4} } & {{\rm 0}{\rm .05} \pm {\rm 0}{\rm .05}} \\ {} & {} & \to & {{\rm CH}_{\rm 2} + {\rm H}_{\rm 2} {\rm O}} & {{\rm 〈 0}{\rm .03}} \\ {} & {} & \to & {{\rm CH}_{\rm 3} {\rm OH}} & {{\rm 〈 0}{\rm .01}} \\ {} & {} & \to & {{\rm CH}_{\rm 2} {\rm O + H}_{\rm 2}} & {{\rm 〈 0}{\rm .002}} \\\end{array}$$\end{document} The method of chemical difference was used to measure the rate constant ratio k4/(k2 + k3), where reactions (2) and (3) are \documentclass{article}\pagestyle{empty}\begin{document}$$\begin{array}{*{20}c} {(2)} & {{\rm O(}^{\rm 1} D{\rm)} + {\rm N}_{\rm 2} {\rm O}} & { \to {\rm N}_{\rm 2} + {\rm O}_{\rm 2} } \\ {(3)} & {} & { \to 2{\rm NO}} \\\end{array}$$\end{document} The CH3 radicals produced in reaction (4) react with the O2 and NO produced in reactions (2) and (3). Thus, near the endpoint of the internal titration, φ{C2H6} gives an accurate measure of k4/(k2 + k3). For the translationally energetic O(1D) atoms produced in the photolysis, k4/(k2 + k3) = 2.28 ± 0.20. However, if He is added to remove the excess translational energy, then k4/(k2 + k3) drops to 1.35 ± 0.3.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040406
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 129
    Electronic Resource
    Electronic Resource
    The reaction of OH with NO2 and the deactivation of O(1D) by CO (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 529-540 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: NO2 was photolyzed with 2288 Å radiation at 300° and 423°K in the presence of H2O, CO, and in some cases excess He. The photolysis produces O(1D) atoms which react with H2O to give HO radicals \documentclass{article}\pagestyle{empty}\begin{document}$$\begin{array}{*{20}c} {{\rm (3)}} & {{\rm O(}^{\rm 1} D{\rm)} + {\rm H}_{\rm 2} {\rm O} \to 2{\rm HO}} \\\end{array}$$\end{document} or are deactivated by CO to O(3P) atoms \documentclass{article}\pagestyle{empty}\begin{document}$$\begin{array}{*{20}c} {{\rm (5)}} & {{\rm O(}^{\rm 1} D{\rm)} + {\rm CO} \to {\rm O(}^{\rm 3} P{\rm) + CO}} \\\end{array}$$\end{document} The ratio k5/k3 is temperature dependent, being 0.33 at 300°K and 0.60 at 423°K. From these two points, the Arrhenius expression is estimated to be k5/k3 = 2.6 exp(-1200/RT) where R is in cal/mole - °K. The OH radical is either removed by NO2 \documentclass{article}\pagestyle{empty}\begin{document}$$\begin{array}{*{20}c} {{\rm (1)}} & {{\rm OH} + {\rm NO}_{\rm 2} {\rm (+M)} \to {\rm HNO}_{\rm 3} {\rm (+M)}} \\\end{array}$$\end{document} or reacts with CO \documentclass{article}\pagestyle{empty}\begin{document}$$\begin{array}{*{20}c} {{\rm (2)}} & {{\rm OH} + {\rm CO} \to {\rm H} + {\rm CO}_{\rm 2} } \\\end{array}$$\end{document} The ratio k2/kα is 0.019 at 300°K and 0.027 at 423°K, and the ratio k2/k0 is 1.65 × 10-5M at 300°K and 2.84 × 10-5M at 423°K, with H2O as the chaperone gas, where kα = k1 in the high-pressure limit and k0[M] = k1 in the low-pressure limit. When combined with the value of k2 = 4.2 × 108 exp(-1100/RT) M-1sec-1, kα = 6.3 × 109 exp (-340/RT)M-1sec-1 and k0 = 4.0 × 1012M-2sec-1, independent of temperature for H2O as the chaperone gas. He is about 1/8 as efficient as H2O.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040507
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 130
    Electronic Resource
    Electronic Resource
    The Reactions of H Atoms with H2S and COSThis work was supported in part by the Sulphur Research Institute and in part by the National Research Council of Canada. (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 547-558 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of the reactions of H atoms with H2S and with COS were measured at 298deg;K in a flow system using mass-spectrometric detection. The rate constants were found to be 3.8 × 10-13 and 2.2 × 10-14 cm3 part-1 sec-1, respectively, with an estimated accuracy of 25%. At high flow rates of H2S, 0.5 molecules of H2S are consumed per H atom originally present. At all flow rates of COS, H2S is a major product, CO production equals COS consumption, and 0.5 molecules of COS are consumed per H atom. The results are consistent with the reaction HS + HS → H2S + S being the dominant process for thiyl radicals, and evidence is presented to indicate that its reaction rate is close to collisional frequency.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040509
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 131
    Electronic Resource
    Electronic Resource
    The Competitive dehydrohalogenation of 1,1,1-trifluoro-2-chloroethane in reflected shock wavesWork supported by the National Research Council of Canada. (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 559-571 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The thermal decomposition of 1,1,1-trifluoro-2-chloroethane has been investigated in the single-pulse shock tube between 1120° and 1300deg;K at total reflected shock pressures from ∼2610 to 3350 torr. Under these conditions, the major reaction is the α,α-elimination of hydrogen chloride, \documentclass{article}\pagestyle{empty}\begin{document}$${\rm CF}_{\rm 3} {\rm CH}_{\rm 2} {\rm Cl}\mathop {{\rm \rightarrow}}\limits^{k_1 } {\rm CF}_{\rm 2} {\rm CHF} + {\rm HCl}$$\end{document} with \documentclass{article}\pagestyle{empty}\begin{document}$${\rm log(}k_1^\infty {\rm, sec}^{ - {\rm 1}} {\rm) = 13}{\rm .3} \pm {\rm 0}{\rm .4} - (65.5 \pm 2.2{\rm kcal})/2.303RT$$\end{document} The decomposition also involves the slower α,β-elimination of hydrogen fluoride, \documentclass{article}\pagestyle{empty}\begin{document}$${\rm CF}_{\rm 3} {\rm CH}_{\rm 2} {\rm Cl}\mathop {{\rm \rightarrow}}\limits^{k_2 } {\rm CF}_{\rm 2} {\rm CHCl} + {\rm HF}$$\end{document} with the first-order rate constant given by \documentclass{article}\pagestyle{empty}\begin{document}$${\rm log(}k_2^\infty {\rm, sec}^{ - {\rm 1}} {\rm) = 12}{\rm .7} \pm {\rm 0}{\rm .5} - (67.6 \pm 2.7{\rm kcal})/2.303RT$$\end{document} At temperatures above 1270°K, two additional minor products were observed. These were identified as CF2CFCl and CF3CHCl2 and suggest C—Cl rupture as a third reaction channel leading to complicated kinetics.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040510
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 132
    Electronic Resource
    Electronic Resource
    Arrhenius parameters for the reactions CH3. + C4H10 → CH4 + C4H9. and C2H5. + C4H10 → C2H6 + C4H9. (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 657-666 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Study of n-butane pyrolysis at high temperature in a flow system allows measurement of the sum of the rate constants of the initiation reactions \documentclass{article}\pagestyle{empty}\begin{document}$$\begin{array}{l} \begin{array}{*{20}c} {(1)} & {{\rm C}_{\rm 4} {\rm H}_{{\rm 10}} \to {\rm 2C}_{\rm 2} {\rm H}_{\rm 5} ^{\rm .} } \\ \end{array} \\ \begin{array}{*{20}c} {(2)} & {{\rm C}_{\rm 4} {\rm H}_{{\rm 10}} \to {\rm CH}_{\rm 3} ^{\rm .} } \\ \end{array} + {\rm C}_{\rm 3} {\rm H}_{\rm 7} ^{\rm .} \\ \end{array}$$\end{document} and of the Arrhenius parameters of the reactions \documentclass{article}\pagestyle{empty}\begin{document}$$\begin{array}{l} \begin{array}{*{20}c} {(3)} & {{\rm CH}_{\rm 3} ^{\rm .} + {\rm C}_{\rm 4} {\rm H}_{{\rm 10}} \to {\rm CH}_{\rm 4} + {\rm C}_{\rm 4} {\rm H}_{\rm 9} ^{\rm .} } \\ \end{array} \\ \begin{array}{*{20}c} {(4)} & {{\rm C}_{\rm 2} {\rm H}_{\rm 5} ^{\rm .} + {\rm C}_{\rm 4} {\rm H}_{{\rm 10}} \to {\rm C}_{\rm 2} {\rm H}_{\rm 6} } \\ \end{array} + {\rm C}_{\rm 4} {\rm H}_{\rm 9} ^{\rm .} \\ \end{array}$$\end{document} Established data for k1/k2 allow estimation of k1 for 951°K and this, with recent thermochemical data, yields the result log k-1 (l.mole s-1) = 8.5, in remarkable agreement with a recent measurement [20] but over si×ty times smaller than conventional assumption. The product k3k4 (l.2mole-2s-2) is found to be associated with the Arrhenius parameters log (A3A4) = 21.90 ± 0.6 and (E3 + E4) = 38.3 ± 2.7 kcal/mole. These values are much higher than would be e×pected on the basis of low temperature estimates. Independent evaluation gives log A4 = 10.5 ± 0.4 (l.mole-1s-1) and E4 = 20.1 ± 1.7 kcal/mole, hence log A3 = 11.4 ± 0.8 (l.mole-1s-1) and E3 = 18.2 ± 3.2 kcal/mole. These values are shown to be entirely consistent with a wide range of results from pyrolytic studies, and it is argued that they further confirm the view that Arrhenius plots for alkyl radical-alkane metathetical reactions are strongly curved, in part due to tunneling and, appreciably, to other as yet unidentified effects. Since there is published evidence that metathetical reactions involving hydrogen atoms show even greater curvature, it is suggested that this may be a characteristic of many metathetical reactions.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040606
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 133
    Electronic Resource
    Electronic Resource
    Rate constants for alkyl radical recombination. II. The isopropyl radical This work has been supported in part by Grant No. AP 00353-06 of the Environmental Protection Agency, Air Pollution Control Administration, and in part by an A.C.S.-P.R.F., Type D, grant. (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 151-157 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Products of radical combination from the free-radical buffer system \documentclass{article}\usepackage{amssymb}\pagestyle{empty}\begin{document}$${{\rm R}^{\rm .} + {\rm R}^{\rm '} {\rm I}\mathop {\leftrightharpoons}\limits^{{\rm K}_{{\rm RR}}}{\rm RI} + {\rm R}^{'}}$$\end{document}. have been analyzed for the two cases, R = Me, R′ = iPr and R = Et, R′ = iPr. Results are consistent with the previously examined system where R = Me, R′ = Et, and give a value of kP for iPr· combination of 108.6±1.1 M-1 sec-1.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040203
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 134
    Electronic Resource
    Electronic Resource
    A quantitative study of alkyl radical reactions by kinetic spectroscopy. II. Combination of the methyl radical with the oxygen molecule (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 129-149 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of the reaction \documentclass{article}\pagestyle{empty}\begin{document}$${\rm CH}_{\rm 3} + {\rm O}_{\rm 2} (+ {\rm M}) \to {\rm CH}_{\rm 3} {\rm O}_{\rm 2} {\rm (+ M)}$$\end{document} have been studied, using the technique of flash photolysis and kinetic spectroscopy to follow the methyl radical concentration. The order of the reaction lies between 2 and 3 throughout the range of pressure from 25 to 380 torr at 22°C, and the results are consistent with a single reaction sequence: \documentclass{article}\pagestyle{empty}\begin{document}$$\begin{array}{l} {\rm CH}_{\rm 3} + {\rm O}_{\rm 2} \mathop {{\rm \rightleftharpoons}}\limits_{\rm b}^{\rm a} {\rm CH}_{\rm 3} {\rm O}_{\rm 2} ^* \\ {\rm CH}_{\rm 3} {\rm O}_{\rm 2} ^* {\rm } + {\rm M}\mathop {{\rm \rightarrow}}\limits^{\rm c} {\rm CH}_{\rm 3} {\rm O}_{\rm 2} {\rm + M} \\ \\\end{array}$$\end{document} The limiting values of the third-order rate coefficients at low pressures are (3.6±0.3) × 1011 1.2 mole-2 sec-1 when M is neopentane, and (0.94 ± 0.03) × 1011 1.2 mole-2 sec-1 when M is nitrogen. The limiting value of the second-order rate coefficient at high pressures is (3.1 ± 0.3) × 108 1. mole-1 sec-1. The rate constant for the independent second-order reaction \documentclass{article}\pagestyle{empty}\begin{document}$${\rm CH}_{\rm 3} + {\rm O}_{\rm 2} \to {\rm CH}_{\rm 2} {\rm O} \to {\rm OH}$$\end{document} is shown to be not much greater than 2 × 105 1. mole-1 sec-1, so that this reaction does not complete significantly with the combination reaction.This new interpretation is contrary to currently accepted views.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040202
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 135
    Electronic Resource
    Electronic Resource
    The Gas-phase thermal unimolecular isomerization of n-propylidenecyclopropylamine to 5-ethyl-1-pyrroline (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 169-174 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The gas-phase thermal isomerization of N-propylidenecyclopropylamine has been studied in the temerature range of 573° to 635°K. The reaction is homogeneous and kinetically first order and yields 5-ethyl-1-pyrroline as the sole product. The rate constants are independent of pressure in the range of 2.5 to 55 torr and fit the Arrhenius relationship log k(sec-1) = (14.05 ± 0.06) - (47.77 ± 0.16)/θ where θ = 2.303 RT in units of kcal/mole, or log k(sec-1) = (14.05 ± 0.06) - (199.9 ± 0.7)/θ, where θ = 2.303RT in kJ/mole. From considerations of a biradical pathway it is concluded that the resonance stabilization energy of the substituted 2-aza-allyl radical is very similar to that of the methallyl radical.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040205
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 136
    Electronic Resource
    Electronic Resource
    Gas and liquid phase kinetics of the unimolecular isomerization of 1-chloro-4-bromobicyclo[2.2.0]hexane: The radical stabilization energy of an α-bromine atom (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 159-168 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of the gas phase isomerization of 1-chloro-4-bromobicyclo[2.2.0]hexane to 2-chloro-5-bromohexa-1,5-diene have been measured in a static system over the temperature range of 135-215°C, with a variation in the total pressure from 0.6 to 400 torr. For these conditions the rate constants are well represented by the Arrhenius equation: \documentclass{article}\pagestyle{empty}\begin{document}$${\rm log (}k{\rm /sec}^{ - {\rm 1}} {\rm)} = {\rm (13}{\rm .2} \pm {\rm 0}{\rm .2)} - (34.5 \pm 0.4)/\theta$$\end{document} where θ = 2.303RT kcal/mole. Transition state estimates for the biradical mechanism for the isomerization of bicyclo[2.2.0]hexanes are shown to be in good agreement with these Arrhenius parameters. By comparison of the activation energy with that for the isomerization of bicyclo[2.2.0]hexane and 1,4-dichlorobicyclo[2.2.0]hexane, the radical stabilization energy of an α-bromine atom is shown to be 1.0 ± 1.8 kcal/mole. Rates are also reported in the liquid phase at temperatures of 155°C and 175°C with diphenyl ether, nitrobenzene, and dimethylsulfoxide as solvents. The observed rate constants are all faster (by a factor of 1.1-1.7) than those measured in the gas phase and display no correlation between rate and solvent polarity.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040204
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 137
    Electronic Resource
    Electronic Resource
    The SO2-sensitized phosphorescence of biacetyl vapor in photolyses at 2650 and 2875 Å. The intersystem crossing ratio in sulfur dioxide (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 175-189 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Quantum yields of the triplet sulfur dioxide (3SO2)-sensitized phosphoresence (Φsens) in biacetyl (Ac2) have been determined in experiments over a wide range of pressures of SO2 and Ac2. Excited singlet sulfur dioxide (1SO2) was generated using 2650-Å and 28757hyphen;Å light. The values of Φsens were dependent on the [SO2]/[Ac2] ratio, as anticpated theoretically. However, in runs at a fixed [SO2]/[Ac2] ratio, the measured Φsens values were dependent on the total pressure. This theoretically unexpected effect is probably largely the result of biacetyl triplet diffusion with deactivation at the cell wall. Treatment of the quantum yield data in terms of the complete mechanism gave new estimates of the following rate functions: 1SO2 + SO2 → (2SO2) (1), 1SO2 + SO2 → 3SO2 + SO2 (2), k2/(k1 + k2) = 0.082 ± 0.003 (2650 Å), 0.095 ± 0.005 (2875 Å) 3SO2 + Ac2 → SO2 + 3Ac2 (9a), 3SO2 + Ac2 → SO2 + Ac2 (9b), k9a + k9b = (8.4 ± 2.1) × 1010 (2650 Å), (8.1 ± 3.0) × 1010 l./mole-sec (2875 Å) 3SO2 → SO2 + hvp (6), k6 = (7.3 ± 1.3) × 101 sec-1.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040206
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 138
    Electronic Resource
    Electronic Resource
    Thermal decomposition of 3-chloro-3-trichloromethyldiazirine in solution (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 229-233 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The thermal decomposition of 3-chloro-3-trichloromethyldizairine in carbon tetrachloride and iso-octane has been investigated over the temperature range 75-115°C. The products, tetrachloroethylene and nitrogen, are formed quantitatively by a first-order reaction which is probably unimolecular: The results yielded the following Arrhenius equations: \documentclass{article}\pagestyle{empty}\begin{document}$$\begin{array}{l} k({\rm CCl}_{\rm 4} {\rm)} = {\rm 10}^{{\rm 13}{\rm .8} \pm {\rm 0}{\rm .2}} \exp (- 29,200 \pm 200/RT)\sec ^{ - 1} \\ k(iso - {\rm octane)} = {\rm 10}^{{\rm 13}{\rm .8} \pm {\rm 0}{\rm .2}} \exp (- 29,000 \pm 150/RT)\sec ^{ - 1} \\ \end{array}$$\end{document}.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040209
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 139
    Electronic Resource
    Electronic Resource
    A study of the intersystem crossing reaction induced in gaseous sulfur dioxide molecules by collisions with nitrogen and cyclohexane at 27°C (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 191-205 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The quantum yields of the sulfur dioxide triplet (3SO2)-sensitized phosphorescence of biacetyl (Φsens) were determined in experiments with N2-SO2-Ac2 and c-C6H12-SO2-Ac2 mixtures excited at 2875 Å at 27°C. The fraction of the biacetyl triplets which reacts homogeneously by radiative or nonradiative decay reactions was determined in a series of runs at constant [SO2]/[M] and [SO2]/[Ac2] ratios but at varied total pressure. A kinetic treatment of the Φsens results and singlet sulfur dioxide (1SO2) quenching rate constant data gave the following new kinetic estimates: 1SO2 + M → (SO2-M) (1b) 1SO2 + M → 3SO2 + M (2b); for 1SO2-N2 collisions, k2b/(k1b + k2b) = 0.033 ± 0.008; for 1SO2-c-C6H12 collisions, k2b/(k1b ± k2b) = 0.073 ± 0.024; previous studies have shown this ratio to be 0.095 ± 0.005 for 1SO2-SO2 collisions. It was concluded that the inter-system crossing ratio in 1SO2 induced by collision is relatively insensitive to the nature of the collision partner M. However, the individual rate constants for the collision-induced spin inversion of 1SO2 (k2b) and the total 1SO2-quenching constants (k1b + k2b) are quite sensitive to the nature of M: k2b/k2a varies from 0.10 ± 0.03 for M = N2 to 1.11 ± 0.37 for M = c-C6H12, and (k1b + k2b)/(k1a + k2a) varies from 0.29 for M = N2 to 1.44 for M = c-C6H12; k1a and k1b are the rate constants for the reactions 1SO2 - SO2 → (2SO2) (1a) and 1SO2 + SO2 → 3SO2 + SO2 (2a), respectively.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040207
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 140
    Electronic Resource
    Electronic Resource
    Emission studies of the mechanism of gaseous biacetyl photolysis at 3450, 3650, 3880, and 4358 a and 28°C (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 207-227 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The quantum yields of phosphorescence (Φp) of biacetyl have been determined in pure biacetyl, biacetyl-SO2, and biacetyl-c-C6H12 mixtures in experiments using bands of radiation centered at 3450, 3650, 3880, and 4348 Å. It has been shown that the unexpected effect of gas concentration on the quantum yields of the sulfur dioxide triplet-sensitized phosphorescence of biacetyl resulted largely from the significant destruction of biacetyl triplets at the wall of the cell. The kinetics of the variation of Φp with [Ac2], wavelength of the absorbed light, and added gases provide new estimates of the energy relations and the rate constants for the decomposition reaction of vibrationally rich biacetyl molecules in the first excited singlet state (1Ac2
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040208
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 141
    Electronic Resource
    Electronic Resource
    A comparative kinetic study of the N-Nitrosation of sulfanilamide by cyclohexyl nitrite and by nitrous acid (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 235-242 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A comparative study of the kinetics of the N-nitrosation of sulfanilamide by cyclohexyl nitrite and by nitrous acid has been made, using an automated technique. The results indicate that a common nitrosating species is effective in analogous reactions involving cyclohexyl nitrite or nitrous acid. The N-nitrosation reaction has been followed spectrophotometrically by coupling the diazotized product with 1-naphthol. Under certain conditions a competitive reaction takes place in which coupling occurs with unreacted sulfanilamide.
    Additional Material: 4 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040210
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 142
    Electronic Resource
    Electronic Resource
    The kinetics of the addition of trichloromethyl radicals to olefins in the gas phase. Recalculation of the data (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 243-247 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040211
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 143
    Electronic Resource
    Electronic Resource
    Arrhenius parameters for the reactions of trichloromethyl radicals (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 249-252 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040212
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 144
    Electronic Resource
    Electronic Resource
    “Kinetic Equations” by Norman Rostoker, Gordon and Breach Science Publishers, Inc., New York, 1971, 346 pp (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 253-253 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040213
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 145
    Electronic Resource
    Electronic Resource
    Masthead (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972) 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040301
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 146
    Electronic Resource
    Electronic Resource
    The rate of destruction of O2 (1Δg) by atomic hydrogen (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 255-264 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: An analysis of the atmospheric observations of O2(1δg) in the dayglow and twilight confirms the crude experimental assessments of Brown [1] and the conclusions that can be made from recent work of Westenberg, Roscoe, and DeHaas [2] that the reaction \documentclass{article}\pagestyle{empty}\begin{document}$${\rm H} + {\rm O}_{\rm 2} (^1 \Delta g) \to {\rm OH} + {\rm O}$$\end{document} is relatively slow, much slower than was expected or can be explained easily in theoretical terms. Using a value for the concentration of atomic hydrogen at 85 km, an upper limit rate of 3×10-13 cm3 molecule-1 sec-1 would be compatible with current atmospheric models. An evaluation of the available data for the rates of several reactions involving ground state or electronically excited species, for which the values are reasonably well established, is included to better analyze the general effects of an electronically excited reactant. This further illustrates the unusual slowness of the H + O2(1Δg) reaction.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040302
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 147
    Electronic Resource
    Electronic Resource
    Rates of reaction of allyl radicals: A reassessment (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 273-276 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Values of the rate constants for allyl-radical abstraction from toluene and allyl-radical recombination have been recalculated in the light of recent data on butene-1 decomposition. The rate of recombination is in good agreement with that found by Van den Bergh and Callear [13] and the cross-combination ratio for the allyl + methyl system has a “normal” value of almost 4. It is concluded that allyl radicals behave like alkyl radicals in respect of their rates of reaction with other radicals.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040304
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 148
    Electronic Resource
    Electronic Resource
    Masthead (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972) 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040401
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 149
    Electronic Resource
    Electronic Resource
    The reaction of CH3N3 with C2H4. A homogenous, bimolecular processAbstracted from a Dissertation submitted by M. S. O'Dell, Jr. to the Graduate school of Arts and Sciences in partial fulfillment of the requirement for the Ph.D. degree of the Catholic University of America. (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 363-365 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040313
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 150
    Electronic Resource
    Electronic Resource
    The reaction of C2F5 radicals with H2S (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 395-403 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reaction of C2F5 radicals with H2S \documentclass{article}\pagestyle{empty}\begin{document}$$\begin{array}{*{20}c} {(2)} & {{\rm C}_{\rm 2} {\rm H}_{\rm 5} + {\rm H}_{\rm 2} {\rm S} \to {\rm C}_{\rm 2} {\rm F}_{\rm 5} {\rm H} + {\rm HS}} & {k_H } \\ \end{array}$$\end{document} was studied over the range 1°-123°C using C2F5 radicals generated by photolysis of perfluoropropionic anhydride. The rate constant kH for reaction (2) is given by \documentclass{article}\pagestyle{empty}\begin{document}$$\log {\rm }k_H ({\rm cm}^{\rm 3} {\rm mole}^{ - 1} \sec ^{ - 1}) = (11.70 \pm 0.19) - (4260 \pm 290)/\theta$$\end{document} where θ = 2.303RT/cal mole-1. The relevance of this result to conflicting published data on the analogous reaction between CF3 radicals and H2S is discussed. It is concluded that there is little difference in the Arrhenius parameters for reaction of CF3 and C2F5 radicals with H2S.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040404
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 151
    Electronic Resource
    Electronic Resource
    Kinetics of the metathetical reaction between carbon tetrachloride and toluene (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 405-416 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A metathetical reaction between carbon tetrachloride and toluene to give benzyl chloride and chloroform occurs at temperatures above 200°C (k = 4.8 × 1010 e-32,900/RT cc mole-1sec-1). The reaction does not involve free radicals, as is shown by the kinetic behavior of the system, by the lack of effect of added free-radical chain inhibitors, and by the absence of the expected chain termination product, hexachloroethane. The reaction is one of a general type between carbon tetrachloride and alkanes or alkylaromatics, but at the temperatures required it is often obscured by dehydrohalogenation of the product to the highly reactive olefin. At high temperatures, benzyl chloride reacts with toluene to give bibenzyl and hydrogen chloride, apparently also by a metathetical reaction. The transition state is postulated to be four-center, in which the carbon-chlorine and carbon-hydrogen bonds are broken and reformed: The experimental preexponential factor is in good agreement with that calculated from transition-state theory.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040405
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 152
    Electronic Resource
    Electronic Resource
    Kinetics of the “a” and “b” band emissions of mercury excimers with added gases (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 449-461 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of the “a” and “b” band emissions arising from the 1Σg+ ← 3Ou and 1Σg+ ← 3lu transitions of the diatomic mercury molecule at λmax ∼ 4850 Å and 3350 Å, respectively, have been studied at low concentrations of mercury in the presence of N2, C2H6, C3H8, and N2O. Rate constant values have been obtained for the following reactions of the excimer molecule: Hg2(3lu) + N2 → Hg2(3Ou) + N2 and Hg2(3Ou) + RH → Hg2(1Σg+) + RH, where RH = C2H6 or C3H8. From a consideration of the detailed kinetics of band emissions, it was also possible to derive rate constants for the quenching reactions of Hg(3P0) atoms. These values are in reasonable agreement with those obtained previously from monitoring atom concentrations directly by 4047 Å absorbiometry.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040408
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 153
    Electronic Resource
    Electronic Resource
    The radiolysis of mixtures of carbon dioxide and hydrogenWork performed under the auspices of the U.S. Atomic Energy Commission. (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 463-477 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The self-radiolysis of CO2 in excess tritium (3H2) has been studied at pressures of 0.1 to 1.0 atm, temperatures of -80° to +100°C, and in the presence of added H2O, He, or Ar. The primary products of decomposition are CO and 3H2O. Secondary products are C3H4, C23H4, and a white polymer. The rates of disappearance of CO2 and formation of products and G-;values were measured. The disappearance of CO2 initially obeys first-order kinetics, then slows down with time at a rate depending upon the initial pressure of 3H2. The initial rates are proportional to pressures of CO2 and 3H2. They are independent of temperature, decreased by addition of H2O vapor, and increased by addition of He or Ar. The proposed mechanism of decomposition of CO2 and formation of products involves ionization of CO2 followed by dissociative recombination forming CO and O. Then the O reacts with a hydrogen-containing species forming OH and H2O, and a back reaction forms CO2 from CO and OH.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040409
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 154
    Electronic Resource
    Electronic Resource
    Masthead (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972) 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040501
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 155
    Electronic Resource
    Electronic Resource
    Very low-pressure pyrolysis. VII. The decomposition of methylhydrazine, 1,1-dimethylhydrazine, 1,2-dimethylhydrazine, and tetramethylhydrazine. Concerted deamination and dehydrogenation of methylhydrazineThis work was supported in part by Air Force Rocket Propulsion Laboratory, Contract No. FO-4611-69-C-0096, and in part by the National Aeronautics and Space Administration Contract No. NAS7-472. (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 433-448 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The rate constants (kuni) for the first-order disappearance of the title molecules have been determined under VLPP conditions. The kuni are not the rate constants of ultimate interest since they reflect the fact that energy transfer competes with the chemical decomposition. Use of the Rice-Ramsperger-Kassel-(Marcus) [RRK(M)] theory allows the determination of the high-pressure rate constants (kα), if the mode of decomposition is known. The heats of formation of the radicals NH2, CH3NH, and (CH3)2N are known. These values should be usable for prediction of the activation energy for N—N bond homolysis in the hydrazines. Measured rate constants for UDMH and TMH bear this out, but the rate constant for MMH does not. This and other evidence lead to the conclusion that MMH decomposes via molecular concerted elimination of NH3 and H2 not and by N—N bond scission. The following values are preferred from this work (θ = 2.303RT in kcal/mole). Mode of decomposition is N - N bond scission unless noted otherwise in parenthesis: \documentclass{article}\pagestyle{empty}\begin{document}$$\begin{array}{ll} \underline{{{{\rm Molecule}}}}& \underline{{{{\rm log }k_\infty /\sec ^{ - 1} (298^\circ {\rm K})}}}\\ {{{{\rm MMH}}}}&{{{13.2{\rm - }54/\theta (- {\rm NH}_{\rm 3});}}}\\ {} & {13.5{\rm - }57/\theta (- {\rm H}_{\rm 2})} \\ {{\rm UDMH}} & {17.0{\rm - }63/\theta } \\ {{\rm SDMH}} & {{\rm 13}{\rm .5 - 57/}\theta {\rm (} - {\rm H}_{\rm 2} {\rm)}} \\ {{\rm TMH}} & {{\rm 17}{\rm .4 - 54/}\theta } \\\end{array}$$\end{document}.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040407
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 156
    Electronic Resource
    Electronic Resource
    Rate constants for radical recombination. III. The trifluoromethyl radicalThis work has been supported in part by Contract No. F44620-71-C-0103 of the Air Force Office of Scientific Research and in part by an A.C.S.-P.R.F., Type D, Grant (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 479-486 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Products of the radical reactions arising from t-Bu2O2, CF3I, and CH3I at 146°C in the vapor phase have been measured over a 33-fold range of CH3I/CH3I ratios and shown to be governed by the rapidly established equilibrium \documentclass{article}\pagestyle{empty}\begin{document}$${\rm Me} \cdot + {\rm CF}_{\rm 3} {\rm I}\mathop {{\rm \rightleftharpoons}}\limits^K {\rm MeI} + {\rm CF}_{\rm 3} \cdot$$\end{document} Together with K estimated by thermochemical methods, the results yield, for the rate of recombination for CF3· radicals, kr = 109.7 ± 0.5 M-1 sec-1.
    Additional Material: 4 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040502
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 157
    Electronic Resource
    Electronic Resource
    The kinetics of chemically induced dynamic nuclear polarization (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 513-520 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040505
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 158
    Electronic Resource
    Electronic Resource
    The rate of the gas phase iodination of cyclobutane. The heat of formation of the cyclobutyl radicalThis work was supported, in part, by Grant No. AP 00353-07 of the Environmental Protection Agency, Air Pollution Control Administration. (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 487-495 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The gas phase iodination of cyclobutane was studied spectrophotometrically in a static system over the temperature range 589° to 662°K. The early stage of the reaction was found to correspond to the general mechanism \documentclass{article}\pagestyle{empty}\begin{document}$$\begin{array}{l} {\rm RH} + {\rm I} \cdot \mathop {{\rm \rightleftharpoons}}\limits^1 {\rm R} \cdot + {\rm HI} \\ {\rm R} \cdot + {\rm I}_{\rm 2} \mathop {{\rm \rightleftharpoons}}\limits^2 {\rm R} - {\rm I} + {\rm I} \cdot \\ \end{array}$$\end{document} where the Arrenius parameters describing k1 are given by log k1/M-1 sec-1 = 11.66 ± 0.11 - 26.83 ± .31/θ, θ = 2.303RT in kcal/mole. The measured value of E1, together with the fact that E-1 = 1 ± 1 kcal/mole, provides ΔHf,2980(c-C4H7.) = 51.14 ± 1.0 kcal/mole, and the corresponding bond dissociation energy, D(c-C4H7—H) = 96.8 ± 1.0 kcal/mole. A bond dissociation energy of 1.8 kcal/mole higher than that for a normal secondary C—H bond corresponds to one half of the extra strain energy in cyclobutene compared to cyclobutane and is in excellent agreement with the recent value of Whittle, determined in a completely different system. Estimates of ΔHf0 and entropy of cyclobutyl iodide are in very good agreement with the equilibrium constant K12 deduced from the kinetic data. Also in good agreement with estimates of Arrhenius parameters is the rate of HI elimination from cyclobutyl iodide.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040503
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 159
    Electronic Resource
    Electronic Resource
    The pyrolyses of tri- and tetramethylethylene in the presence of nitric oxide (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 49-60 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The pyrolyses of trimethylethylene and tetramethylethylene have been investigated in the presence and absence of nitric oxide. It appears that apart from a unimolecular split, e.g., a disproportionation reaction such as may play an important role in initiation. Nitric oxide had no effect on H2 production, which is probably a molecular process. There was similar behavior of both compounds in the presence of NO, indicating that the olefinic hydrogen atom does not play a decisive role. Other aspects of the mechanisms are discussed.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040104
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 160
    Electronic Resource
    Electronic Resource
    The decomposition of chemically activated n-butane, isopentane, neohexane, and n-pentane and the correlation of their decomposition rates with radical recombination rates.Abstracted in part from the Ph.D. Thesis of W. L. Hase, New Mexico State University, 1970.The National Science Foundation is gratefully acknowledged for financial support (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 1-35 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The total decomposition rates of the chemically activated alkanes n-butane, n-pentane, isopentane, and neohexane were measured using an internal comparison technique. Chemical activation was by the C—H insertion reaction of excited singlet-state methylene radicals. A total of ten rate constants ranging from 4.6 × 105 to 2.3 × 107 sec-1 were measured for these alkanes at different excitation energies. These rates correlate via RRKM theory calculations with thermal A-factors in the range of 1016.1 to 1017.1 sec-1 for free rotoractivated complex models and in the range of 1016.4 to 1017.8 sec-1 for vibrator-activated complex models. It was found that high critical energies for decomposition, “tight” radical models, and activated complex models with free internal rotations were required to correlate the decomposition rates of these alkanes with estimated alkyl radical recombination rates. The correlation is just barely possible even for these favorable extremes, indicating that there may be a basic discrepancy between the recombination rate and decomposition rate data for alkanes.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040102
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 161
    Electronic Resource
    Electronic Resource
    Kinetics of the formation of cyclobutane from ethylene (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 61-68 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The rate of the thermal reaction of ethylene to form cyclobutane has been measured over the temperature range 723°-786°K and at pressures between 300 and 1300 torr. The equilibrium constant for the system \documentclass{article}\usepackage{amssymb}\pagestyle{empty}\begin{document}$${\rm 2C}_{\rm 2} {\rm H}_{\rm 4}\mathop {\leftrightharpoons}\limits_{kf}^{kr} c - {\rm C}_{\rm 4} {\rm H}_{\rm 8}$$\end{document} was calculated both from the initial rate data and from measurements of the equilibrium concentration of cyclobutane. Agreement with the reported thermodynamic quantities for cyclobutane was satisfactory. The initial rate data gave the following epxression for kf: \documentclass{article}\pagestyle{empty}\begin{document}$${\rm log }k_f {\rm (1}{\rm .mole}^{ - {\rm 1}} {\rm sec}^{ - {\rm 1}} {\rm)} = {\rm 7}{\rm .84} - \frac{{43800}}{{2.3RT}}$$\end{document} while the measurements of the equilibrium concentration of cyclobutane gave the expression for K, \documentclass{article}\pagestyle{empty}\begin{document}$${\rm log }K{\rm (atm}^{ - {\rm 1}} {\rm)} = - \frac{{45.4}}{{2.3R}} + \frac{{20700}}{{2.3RT}}$$\end{document}.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040105
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 162
    Electronic Resource
    Electronic Resource
    The rate of dissociation of allyl iodide in shock wavesWork supported in part by the Army Research Office, Durham, N. C. (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 87-102 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The rate of decomposition of allyl iodide has been measured from 742plusmn;K to 1068±K and from 169 to 1429 torr using a shock tube method in which the disappearance of allyl iodide and the appearance of iodine are followed simultaneously. The kinetics are first order in allyl iodide and probably are slightly dependent upon total pressure. Mathematical modeling shows that they are compatible with a mechanism consisting of three reactions: The experiments yield the rate constant k1, the high-pressure limiting value of which is found to be \documentclass{article}\pagestyle{empty}\begin{document}$$\log _{10} k_\infty (\sec ^{ - 1}) = (14.45 \pm 0.4) - (42.8 \pm 2.4{\rm kcal})/2.3RT$$\end{document} in reasonable agreement with that predicted using the methods of Benson and O'Neal [1].
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040108
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 163
    Electronic Resource
    Electronic Resource
    Bromination of dichloromethane, chlorofluoromethane, and dichlorofluoromethaneThis paper is part XXIV of the series “Free Radical Substitution in Aliphatic Compounds.” For part XXIII, see ref [1]. (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 69-77 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Dichloromethane, chlorofluoromethane, and dichlorofluoromethane have been brominated competitively with each other and with chloroform and methyl chloride. Using the literature values for the rates of bromination of these latter two compounds, the rate constants for the three former compounds have been determined: \documentclass{article}\pagestyle{empty}\begin{document}$$\begin{array}{l} k_2 ({\rm CH}_{\rm 2} {\rm Cl}_{\rm 2} {\rm)} = (9.77 \pm 1.44) \times 10^9 \exp (- 10,860 \pm 480{\rm cal}/RT) \\ k_2 ({\rm CH}_{\rm 2} {\rm F Cl)} = (7.76 \pm 1.59) \times 10^{10} \exp (- 14,800 \pm 800{\rm cal}/RT) \\ k_2 ({\rm CHF Cl}_{\rm 2} {\rm)} = (1.05 \pm 1.48) \times 10^{10} \exp (- 13,300 \pm 570{\rm cal}/RT) \\ \end{array}$$\end{document} where R is taken to be 1.987 cal deg-1 mol-1 (1 cal = 4.186 J).
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040106
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 164
    Electronic Resource
    Electronic Resource
    The reactions of C2F5 radicals with benzene in the vapor phase (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 79-86 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: C2F5 radicals were generated in the presence of benzene vapor by the reaction \documentclass{article}\pagestyle{empty}\begin{document}$$({\rm C}_{\rm 2} {\rm F}_{\rm 5} {\rm CO})_2 {\rm O} + hv \to {\rm CO} + {\rm CO}_2 + 2{\rm C}_{\rm 2} {\rm F}_5 $$\end{document} The radicals react with the benzene by addition and pseudo H abstraction The rate constant kadd for the addition reaction (7) is given by \documentclass{article}\pagestyle{empty}\begin{document}$$\log k_{add} /k_{c^{1/2} } {\rm cm}^{{\rm 3/2}} {\rm mole}^{ - 1/2} \sec ^{ - 1/2} = (4.49 \pm 0.10) - (4210 \pm 150)/\theta $$\end{document} where θ = 2.303RT cal/mole and kc is the rate constant for combination of C2F5 radicals. The addition becomes reversible above 110°C. The reactions of CF3 and C2F5 radicals with benzene vapor are compared.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040107
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 165
    Electronic Resource
    Electronic Resource
    The kinetics of the reactions of O(3P) atoms with dimethyl ether and methanol (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 103-116 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of the reaction of O + CH3OCH3 were investigated using fast-flow apparatus equipped with ESR and mass-spectrometric detection. The concentration of O(3P) atoms to CH3OCH3 was varied over an unusually large range. The rate constant for reaction \documentclass{article}\pagestyle{empty}\begin{document}$${\rm O} + {\rm CH}_{\rm 3} {\rm OCH}_3 \to {\rm OH} + {\rm CH}_{\rm 2} {\rm OCH}_{\rm 3} $$\end{document} was found to be k = (5.0 ± 1.0) × 1012 exp [(-2850 ± 200/RT)] cm3 mole-1 sec-1. The reaction O + CH3OH was studied using ESR detection. Based on an assumed stoichiometry of two oxygen atoms consumed per molecule of CH3OH which reacts, we obtain a value of k = (1.70 ± 0.66) × 1012 exp [(-2,280 ± 200/RT)] cm3 mole-1 sec-1 for the reaction \documentclass{article}\pagestyle{empty}\begin{document}$${\rm O} + {\rm CH}_{\rm 3} {\rm OH} \to {\rm OH} + {\rm CH}_{\rm 2} {\rm OH}$$\end{document} The results obtained in this study are compared with the results from other workers on these reactions. The observation of essentially equal activation energies in these two reactions is indicative of approximately equal C—H bond strengths in CH3OCH3 and CH3OH. This is in agreement with recent measurements of these bond energies.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040109
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 166
    Electronic Resource
    Electronic Resource
    Masthead (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972) 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040201
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 167
    Electronic Resource
    Electronic Resource
    Kinetics of the thermal reaction of 1,1,2-trimethylcyclopropane (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 117-126 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The gas-phase reaction kinetics of 1,1,2-trimethylcyclopropane have been studied in the temperature range of 700-755°K. First-order unimolecular rate constants for over-all reactant disappearance fit the Arrhenius equation \documentclass{article}\pagestyle{empty}\begin{document}$${\rm log }k_0 {\rm (sec}^{ - {\rm 1}} {\rm)} = {\rm 14}{\rm .47} - \frac{{61.08 \pm 0.51}}{\theta }$$\end{document} Reaction products and the relative rates of their formation are found to be reasonably consistent with the biradical mechanism.
    Additional Material: 4 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040110
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 168
    Electronic Resource
    Electronic Resource
    A flash photolysis-resonance fluorescence kinetics study of ground-state sulfur atoms. II. Rate parameters for reaction of S(3P) with C2H4 (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 383-394 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Absolute rate constants for the reaction of S(3P) with ethylene were measured over an ethylene concentration range of 7, a total pressure of 50 to 400 torr, and a flash intensity range of 10. At 298°K, the bimolecular rate constant was found to be invariant over this range of variables and had a measured value of 4.96 × 10-13 cm3 molec-1 s-1. Over the temperature range of 218° to 442°K, the rate data could be fit to a simple Arrhenius equation of the form \documentclass{article}\pagestyle{empty}\begin{document}$$k_1 = (7.13 \pm 0.74) \times 10^{ - 12} {\rm exp}\left({\frac{{{\rm - 1}{\rm .58} \pm {\rm 0}{\rm .08 kcal/mole}}}{{RT}}} \right)$$\end{document} Units are cm3 molec-1 s-1. The dependence of the measured value of k1 on the concentration of the reaction product ethylene episulfide is discussed.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040403
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 169
    Electronic Resource
    Electronic Resource
    The photolysis of N2O at 2139 Å and 1849 Å (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 497-512 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The method of chemical difference was utilized to accurately determine the relative importance of all the reaction steps in the direct photolysis of N2O at 2139 Å (25° and 250°C) and 1849 Å (25° C), as well as in the Hg6(1P1)-sensitized photolysis of N2O at 1849 Å (25°C). In all cases, the primary process is predominantly, if not exclusively, \documentclass{article}\pagestyle{empty}\begin{document}$$\begin{array}{*{20}c} {{\rm (1)}} & {{\rm N}_{\rm 2} {\rm O} + hv{\rm or H}_{\rm g} 6(^1 P_1) \to {\rm N}_{\rm 2} + {\rm O(}^{\rm 1} D{\rm)}} \\\end{array}$$\end{document} Experiments with trace amounts of C3H6 added showed a slight, but not significant, difference in product ratios (N2 and O2). From these experiments the quantum yield of O(3P) from all possible sources was estimated as 0.02 ± 0.02. Experiments with excess N2 at 1849 Å indicated that O(1S) was not produced in the direct photolysis. The O(1S) yield is probably zero, and certainly 〈0.05. The O(1D) atom can react with N2O via \documentclass{article}\pagestyle{empty}\begin{document}$$\begin{array}{l} \begin{array}{*{20}c} {{\rm (2)}} & {{\rm O(}^{\rm 1} D{\rm)} + {\rm N}_{\rm 2} {\rm O} \to {\rm N}_{\rm 2} + {\rm O}_2 } \\\end{array} \\ \begin{array}{*{20}c} {{\rm (3)}} & {{\rm O(}^{\rm 1} D{\rm)} + {\rm N}_{\rm 2} {\rm O} \to 2{\rm NO}} \\\end{array} \\ \end{array}$$\end{document} The ratio k2/k3 was found to be 0.69 ± 0.05 in all cases. When combined with other data from our laboratory, the average value is 0.65 ± 0.07. This represents the value for translationally energetic O(1D) atoms. When excess He was added to remove the excess translational energy, k2/k3 rose to 0.83 ± 0.06, which is in reasonable agreement with the value of 1.01 ± 0.06 found in another laboratory. We conclude that for O(1D) atoms with no excess thermal energy, k2/k3 = 0.90 ± 0.10.
    Additional Material: 4 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040504
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 170
    Electronic Resource
    Electronic Resource
    Rates of reaction of atomic oxygen with C2H3F, C2H3Cl, C2H3Br, 1,1-C2H2F2, and 1,2-C2H2F2 (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 521-527 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Rate constants for the reactions of atomic oxygen (O3P) with C2H3F, C2H3Cl, C2H3Br, 1,1-C2H2F2, and 1,2-C2H2F2 have been measured at 307°K using a discharge-flow system coupled to a mass spectrometer. The rate constants for these reactions are (in units of 1011 cm3 mole-1 s-1) 2.63 ± 0.38, 5.22 ± 0.24, 4.90 ± 0.34, 2.19 ± 0.18, and 2.70 ± 0.34, respectively. For some of these reactions, the product carbonyl halides were identified.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040506
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 171
    Electronic Resource
    Electronic Resource
    Pyrolysis of 4,4-bisperfluoromethylbutene-1,4 01 in the gas phase (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 541-545 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Pyrolysis of (CF3)2C(OH)CH2CH=CH2, the reverse of the reaction between perfluoroacetone and propene, has been studied in the gas phase between 475° and 598°K. Even at 573°K, the unimolecular reaction rate constant appears to be in its pressure-independent region at 20.0 torr pressure. In a quartz vessel, the decomposition is homogeneous. The specific unimolecular rate constant is \documentclass{article}\pagestyle{empty}\begin{document}$$k = T^{1/2} 10[^{(10.3 \pm 0.10) - (\frac{{40300 \pm 300}}{{4.575T}})}]\sec ^{ - 1}$$\end{document} where the limits are for one standard deviation. Combining these results with the previously reported results on the reverse reaction, the equilibrium constant for the reaction \documentclass{article}\pagestyle{empty}\begin{document}$${\rm C}_{\rm 3} {\rm H}_{\rm 6} + {\rm CF}_{\rm 3} {\rm COCF}_{\rm 3} {\rm \rightleftharpoons(CF}_{\rm 3} {\rm)}_{\rm 2} {\rm C(OH)CH}_{\rm 2} {\rm CH = CH}_{\rm 2}$$\end{document} is \documentclass{article}\pagestyle{empty}\begin{document}$$k_p = 10[^{(1/4.575)(-34.0 \pm 1.0) + (\frac{{18700 \pm 400}}{T})}]atm^{ - 1}$$\end{document} It is noteworthy that in the temperature range of the study of the forward reaction (448° to 573°K), the percentage of back reaction in the times of the experiments varies from less than 0.1 to 1.5. Using group additivities and the above ΔH0, ΔHf0 of (CF3)2CO is calculated to be -325.2 kcal/mole at 600°K and the average C—C bond is 42.0 kcal/mole.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040508
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 172
    Electronic Resource
    Electronic Resource
    Masthead (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972) 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040601
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 173
    Electronic Resource
    Electronic Resource
    Table of the Kassel integralThis work was supported by the U.S. Air Force under Contract F04701-71-C-0172. (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 591-637 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: An e×tensive table is given of the Kassel integral \documentclass{article}\pagestyle{empty}\begin{document}$$I(S,B,D) = \Gamma \mathop {(S)}\limits^1 \int_0^\infty {\frac{{x^{S - 1} e^{ - x} dx}}{{1 + 10^D \left({\frac{x}{{B + x}}} \right)^{S - 1} }}}$$\end{document} that occurs in the Rice-Ramsperger-Kassel theory of unimolecular gas reactions.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040603
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 174
    Electronic Resource
    Electronic Resource
    Decay kinetics of the triplet and anthrasemiquinone radicals in aqueous organic media (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 639-644 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Electron transfer involving triplet molecules of anthraquinone sulfonates has been studied by flash photolysis. It was revealed that semiquinone radicals were formed in one-electron oxidation of carbonate anions. Absorption spectra and the kinetics of decay transients in aqueous and aqueous-alcoholic solutions have been studied.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040604
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 175
    Electronic Resource
    Electronic Resource
    The mechanism of thermal dehydrochlorination. Pyrolysis of 1-Chloro-1-fluoroethane and 1-chloro-1, 1-difluoroethane (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 645-655 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The thermal decompositions of 1-chloro-1-fluoroethane and 1-chloro-1,1-difluorethane at atmospheric pressure have been studied in the temperature range 500-600°C in a flow system. The dehydrochlorinations are homogenous in a carbonaceous reactor and unimolecular. The rate constants are given by \documentclass{article}\pagestyle{empty}\begin{document}$$k_{\rm I} = 10^{13.94 \pm 0.05} \exp (- 57,015 \pm 200/RT)^{\sec - 1}$$\end{document} and \documentclass{article}\pagestyle{empty}\begin{document}$$k_{{\rm II}} = 10^{14.35 \pm 0.12} \exp (- 60,200 \pm 500/RT)^{\sec - 1}$$\end{document} The criteria for molecular or chain processes in thermal dehydrochlorinations are discussed.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040605
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 176
    Electronic Resource
    Electronic Resource
    A Kinetic study of the reaction of nitrogen dioxide with tetrafluoroethylene (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 575-589 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reaction of NO2 with C2F4 was studied at 30°, 68°, 114°, and 157°C by in situ monitoring the infrared absorption bands of the products. The major primary products of the reaction are O2NCF2CFO and FNO. Smaller amounts of CF2O (and presumably NO) are also produced. There was no evidence for other primary products, though they may have been produced in minor amounts. The rate laws for the production of both O2NCF2CFO and CF2O are first order in both [NO2] and [C2F4]. CF2O production is at least partly heterogeneous as demonstrated by packing the quartz reaction vessel with Pyrex beads and by using a Monel cell. The homogeneous rate constant obtained from the high-temperature results gives a rate constant of 3.4 × 108 exp (minus;17000/RT) M-1sec-1 for CF2O production. Actually these Arrhenius parameters represent lower limits, since the heterogeneous reaction may still be playing a significant role. The production rate of O2NCF2CFO is not much affected by changing the nature of the surface or the surface to volume ratio. However the reaction may be heterogeneous, since the rate constant for its formation of 1.3 × 104 e×p (-7500/RT) M-1sec-1 has an abnormally low pree×ponential factor. E×periments in the presence of NO indicate that the mechanism for O2NCF2CFO formatlon is \documentclass{article}\pagestyle{empty}\begin{document}$$\begin{array}{l} \begin{array}{*{20}c} {(11)} & {{\rm NO}_{\rm 2} + {\rm C}_{\rm 2} {\rm F}_{\rm 4} \to {\rm O}_{\rm 2} {\rm NCF}_{\rm 2} {\rm CF}_{\rm 2} } \\ \end{array} \\ \begin{array}{*{20}c} {(12)} & {{\rm O}_{\rm 2} + {\rm NCF}_{\rm 2} {\rm CF}_{\rm 2} + {\rm NO}_{\rm 2} \to {\rm O}_{\rm 2} {\rm NCF}_{\rm 2} {\rm CFO} + {\rm FNO}} \\ \end{array} \\ \end{array}$$\end{document} The intermediate can also react with NO: \documentclass{article}\pagestyle{empty}\begin{document}$$\begin{array}{*{20}c} {(13)} & {{\rm O}_{\rm 2} {\rm NCF}_{\rm 2} {\rm CF}_{\rm 2} + {\rm NO} \to {\rm O}_{\rm 2} {\rm NCF}_{\rm 2} {\rm CF}_{\rm 2} {\rm NO}} \\ \end{array}$$\end{document} with k13/k12 = 1.3.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040602
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...