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  • Scanning electron microscopy  (15)
  • Chromatographie, Gas  (9)
  • Springer  (24)
  • American Chemical Society
  • Blackwell Publishing Ltd
  • Taylor & Francis
  • 2020-2023
  • 2020-2020
  • 2005-2009
  • 1975-1979  (24)
  • 1965-1969
  • 1950-1954
  • 1945-1949
  • 1940-1944
  • 1975  (24)
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  • Springer  (24)
  • American Chemical Society
  • Blackwell Publishing Ltd
  • Taylor & Francis
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  • 2020-2023
  • 2020-2020
  • 2005-2009
  • 1975-1979  (24)
  • 1965-1969
    • +
Year
  • 1
    Electronic Resource
    Electronic Resource
    The surface of the pecten oculi in the pigeon (1975)
    Springer
    Cell & tissue research 157 (1975), S. 457-465 
    Details
    ISSN: 1432-0878
    Keywords: Pecten oculi ; Pigeon ; Surface ; Function ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary A scanning electron microscopic study of the pecten reveals the rib-like character of the pectinal folds, the nature of their connections with the base and bridge of the pecten as well as the presence of interconnections between the bundles of superficial collagenous fibres. It has been suggested that the pecten may have a mechanical significance, namely protection of the retina from the excessive movements of the vitreous humour. The relationship between the superficial membrane of the folds which is continuous, the intercellular spaces and the process of diffussion has also been discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00222599
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  • 2
    Electronic Resource
    Electronic Resource
    Osteoblasts and collagen orientation (1975)
    Springer
    Cell & tissue research 159 (1975), S. 73-80 
    Details
    ISSN: 1432-0878
    Keywords: Osteoblasts ; Collagen orientation ; Parietal bone ; Rat, Rhesus monkey ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Bone was removed from the calvaria of anaesthetized 70 g rats or freshly killed young monkeys and the fibrous periosteum dissected off the inner, formative surface under 0.15 M cacodylate buffer. The bone and undisturbed osteoblasts were fixed in 3% glutaraldehyde in the same buffer for 24 to 48 hours, critical point dried and coated with evaporated carbon and gold for scanning electron microscopy (SEM). Fields of osteoblasts were photographed and chosen cells dissected off the osteoid using a tungsten needle. The control of the dissection was made possible by the use of a system of real-time stereo TV-speed SEM. The fields were rephotographed and the orientations of the osteoblasts were compared with that of the underlying collagen fibres. 62% of all osteoblasts lay with their long axes within 15° of the collagen fibre orientation below and 80% within 30°. Montages of large areas of osteoblasts were also made, and then compared with ones of the same area after the cells had been stripped off on adhesive tape. In general, the orientation of the collagen tended to be the same as the cell that formed it. Collagen fibres below cells at the periphery of a domain sometimes had the orientation of the cells in the adjacent patch. It is not possible to determine whether the cells controlled the orientation of the collagen, or vice versa, from this experiment, but other SEM evidence suggests that the collagen orientation in hard tissue matrices depends on the freedom of cells to move with respect to the matrix surface.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00231996
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  • 3
    Electronic Resource
    Electronic Resource
    Scanning electron microscopic studies of the rat incisor odontoblastema (1975)
    Springer
    Cell & tissue research 159 (1975), S. 233-243 
    Details
    ISSN: 1432-0878
    Keywords: Odontoblasts ; Predentine ; Dentine ; Calcification ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary A scanning electron microscopic technique was used to investigate the surface structure of dentinogenically active odontoblasts. Thin pieces of rat incisors were fixed, rapidly frozen, freezedried at -70° C and fractured to expose new surfaces prior to examination in the SEM. Differences in the appearance of odontoblastic cell surfaces were seen, with the most extensive ridge formations at the distal part of the sides of the odontoblasts. The predentine area displayed a spongy structure which contrasted to the compact appearance of dentine. Results are discussed in relation to previous studies at the light microscopic and transmission electron microscopic levels.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00219159
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  • 4
    Electronic Resource
    Electronic Resource
    Electron microscopic studies of the lung of the frog (1975)
    Springer
    Cell & tissue research 160 (1975), S. 399-410 
    Details
    ISSN: 1432-0878
    Keywords: Lung ; Frog ; Alveolar epithelium ; Mucus layer ; Scanning electron microscopy ; Transmission electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Scanning and transmission electron microscopy were used to study the inner architecture of the frog lung. In some specimens the alveolar surface mucus layer was removed to permit the examination of underlying features. The inner surface of the frog's lung is covered by a layer of microvilli belonging to only one type of epithelial cells. The boundaries of these epithelial cells are demarcated by small ridges. Different degrees of lung expansion cause variations of the surface topography. The morphology of certain surface features is examined in detail. Several methods of drying the specimens are compared.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00222048
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  • 5
    Electronic Resource
    Electronic Resource
    Comparative scanning electron microscope study of boar, bull and ram spermatozoa (1975)
    Springer
    Cell & tissue research 161 (1975), S. 329-341 
    Details
    ISSN: 1432-0878
    Keywords: Spermatozoa ; Boar, bull, ram ; Surface ultrastructure ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé La morphologie comparée des spermatozoïdes éjaculés de Verrat, Taureau et Bélier a été étudiée au microscope à balayage. Le sperme lavé est fixé dans le glutaraldéhyde ou le mélange acide picrique-formaldéhyde-glutaraldéhyde. Les échantillons sont le plus souvent désséchés par la méthode du point critique (Fréon) sur un filtre et aussi dans l'air sur une lamelle de verre. La tête des spermatozoïdes de ces trois espèces présente la même forme en pagaie aplatie formée de trois régions principales: les deux segments, antérieur, entouré d'un épaississement marginal, et équatorial de l'acrosome et la région postacrosomique. La plupart des differentiations de la lame postacrosomique décrites en microscopie électronique à transmission sont visibles à travers la membrane plasmique, particulièrement après dessication à l'air. La morphologie superficielle du cou et des différentes parties du flagelle est aussi observable. Des différences spécifiques sont mises en évidence: chez le verrat seulement, par exemple, la surface de l'acrosome apparaît granuleuse, et aucune bordure antérieure dentelée de la lame postacrosomique n'est visible. La microscopie à balayage permet d'observer les grands traits et de fins détails de la morphologie superficielle d'un échantillon de sperme et aussi d'étudier les effects de traitements sur des spermatozoïdes (congélation, extraction de l'acrosome).
    Notes: Summary The comparative ultrastructure of ejaculated boar, bull and ram spermatozoa is studied by scanning electron microscopy. After washing, the spermatozoa are fixed in glutaraldehyde or in picric acid-formaldehyde-glutaraldehyde mixture. Samples are prepared either by critical point drying (Freon) on Millipore filters or by air drying on glass cover slips. In all the species studied, three regions may be distinguished in the paddle-shaped head of the sperm: an anterior segment (surrounded by the marginal thickening) and an equatorial segment constituting together the acrosome, and the postacrosomal region. Most of the feature of the postacrosomal lamina described in transmission electron microscopy are visible through the plasma membrane, particularly after air drying. The surface morphology of the neck and of the different segments of the flagellum is also evident. Some species differences are encountered, e.g. rough surface of acrosome and absence of serrations in postacrosomal lamina of boar spermatozoa only. The techniques employed result in good general morphology and fine resolution of surface detail of the sperm samples; they also permit analysis of spermatozoa treated by freezing or submitted to acrosomal extraction.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00220002
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  • 6
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    The surface fine structure of the bovine subcommissural organ (1975)
    Springer
    Cell & tissue research 163 (1975), S. 125-132 
    Details
    ISSN: 1432-0878
    Keywords: Bovine subcommissural organ ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The bovine subcommissural organ was studied by using scanning electron microscopy. The most prominent finding was the existence of protruded and dilated endings of the ependymal cells. The majority of these cells were ciliated with two or more cilia; only a few unciliated cells were seen. Some pore-like structures were also seen on the surface. From the functional point of view, the most interesting finding was an amorphous heterogeneous material on the subcommissural ependyma. Especially in the caudal part of the organ this material accumulated in abundance. No real filamentous structures such as Reissner's fibre could be seen, however, it was assumed that the heterogeneous material corresponds to this formation. No supraependymal neurones were demonstrated.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00221721
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  • 7
    Electronic Resource
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    Neuronal migration during the early development of the cerebral cortex (1975)
    Springer
    Cell & tissue research 163 (1975), S. 313-325 
    Details
    ISSN: 1432-0878
    Keywords: Neurogenesis ; Cerebral cortex ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Fixed cerebral vesicles of mouse foetuses were fractured and examined with the scanning electron microscope. This method provides a study of the three dimensional developmental features of the pseudostratified columnar epithelium up to the formation of the early cortex plate. Matrix cells are a cell population of homogeneous shape, however, mitotic cells are easily identified by their spherical form. The external surface of the brain is formed by the closely packed end feet of these cells covered by a basal membrane. The formation of the cortical plate is the result of a continuous cell migration in columnar arrangement towards the pia. Glioependymal cells extend along the whole brain wall and most likely provide guidance for the migrating cell cords. The formation of the so-called migratory zone is a consequence of the growth of the basal and the horizontal prolongations of emigrating cells. The significance of the cell to cell contacts for the neuronal migration processes is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00219466
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  • 8
    Electronic Resource
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    The distal ommatidium of the compound eye of the housefly (Musca domestica): A scanning electron microscope study (1975)
    Springer
    Cell & tissue research 159 (1975), S. 379-385 
    Details
    ISSN: 1432-0878
    Keywords: Compound eye ; Musca domestica ; Ommatidium ; Distal retinula ; Scanning electron microscopy ; Corneal lens ; Corneal pigment cell ; Pseudocone ; Semper cell ; Basement membrane
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The distal aspect of the housefly ommatidium was surveyed by the scanning electron microscope. Attention was directed to the somal eminence of the superior central cell and the lens to large pigment cell junction. The underside of each lens facet exhibits six hexagonally arranged incisures. Into each of these indentations are fitted several large pigment cells. This hexagonal indentation appears to be a tenacious anchorage. Two corneal pigment cells laterally encircle the pseudocone and at their proximal extension they enclose the Semper cells and neck of the retinula. The somal eminence of the superior central cell is about 10 μm from the base of the corneal pigment cell enclosure. Micrographs were used to construct a diagram of the ommatidium above the basement membrane. Suggestions are made as to the functional correlates of the observed ommatidial structures.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00221784
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  • 9
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    Light- and scanning electron microscopical studies of the hypothalamo-adenohypophysial portal vessels of the toad Bufo bufo (L.) (1975)
    Springer
    Cell & tissue research 162 (1975), S. 131-139 
    Details
    ISSN: 1432-0878
    Keywords: Hypothalamo-adenohypophysial region Bufo bufo (L.) ; Portal vessels ; Methyl-methacrylate casts ; Light microscopy ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The vascularization of the hypothalamo-adenohypophysial region of the toad Bufo bufo (L.) (Amphibia, Anura) was studied by means of light- and scanning electron microscopy. Special attention was given to the portal vascular system of the median eminence and the pars distalis. Course and arrangement of these vessels are described.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00223268
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  • 10
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    Surface fine structure of the globiferous pedicellariae of the regular echinoid, Psammechinus miliaris gmelin (1975)
    Springer
    Cell & tissue research 162 (1975), S. 377-385 
    Details
    ISSN: 1432-0878
    Keywords: Globiferous pedicellariae ; Psammechinus miliaris ; Microvilli ; Chemoreceptor ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The globiferous pedicellariae of Psammechinus miliaris are described. Two fixation methods giving minimal distortion and rapid tissue hardening were adapted for soft tissue preparation for scanning electron microscopy. The pedicellarial valves are covered by a microvillous epithelium. The outer valve epithelial microvilli overlying red spherulocytes in the epidermis are characterized by a filament matrix radiating out from each microvillus. These microvilli may function in epidermal absorption of organic solutes. The inner valve microvilli are more densely packed and the filament matrix is absent. Ciliation is confined to the inner valve surface where the cilia are concentrated to form a distal sensory pad and sensory hillock. Behavioural evidence suggests a chemo- and mechanosensory role for the inner valve surface.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00220184
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  • 11
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    A scanning electron microscopic study of the rat liver sinusoid (1975)
    Springer
    Cell & tissue research 164 (1975), S. 371-385 
    Details
    ISSN: 1432-0878
    Keywords: Kupffer cell ; Endothelial cell ; Sinusoid ; Liver ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The surface ultrastructure of Kupffer cells in the rat liver has been studied by scanning electron microscopy (SEM). The results demonstrate that Kupffer cells are both significantly different and clearly distinct from endothelial cells. Kupffer cells have neither pores (and/or “sieve plates”) nor fenestrations, all of which are present in endothelial cells. They possess a stellate shape, and only indirectly, with slender and irregular evaginations, contribute to the lining of the sinusoidal wall. Furthermore, the luminal surface in some areas contains a large population of short microvilli, microplicae and invaginations. These elements form a kind of microlabyrinth which may correspond to the “worm-like” structures described by transmission electron microscopy (TEM). In the present study, transition forms between endothelial and Kupffer cells were never found. On the contrary, considering the highly fenestrated nature of the endothelial cells, the Kupffer cells may, by ameboid movements, easily cross the overlapping barrier of the sinusoid and protrude into the lumen. Thus, acting as activated macrophages, the Kupffer cells might function to prevent the entrance of foreign material into the tissues of the liver through the fragile and highly fenestrated endothelium. Finally, the topographical reconstruction of the sinusoid by correlated SEM and TEM studies demonstrates that Kupffer cells, with their protruding cytoplasm and ability to extend into the lumen of the sinusoid, may actually change the caliber of the vessel, and thus function as a “sphincter” which causes a temporary arrest of the blood flow when the diameter of the sinusoidal lumen is reduced.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00223015
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  • 12
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    Scanning electron microscope observations on the muscle innervation of Oikopleura dioica fol (appendicularia, tunicata) with notes on the arrangement of connective tissue fibres (1975)
    Springer
    Cell & tissue research 164 (1975), S. 357-369 
    Details
    ISSN: 1432-0878
    Keywords: Neuromuscular junctions ; Appendicularia (Oikopleura dioica) ; Connective tissue fibrils ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Critical point dried and fractured appendicularia of the species Oikopleura dioica have been examined in the scanning electron microscope. The dorsal nerve cord with ganglion cells and peripheral nerve fibres could easily be observed. Thick peripheral nerve fibres leave the nerve cord as bilateral pairs at constant intervals along the tail. Most of these fibres branch from the naked nerve cord, but some evidently originate in ganglion perikarya bulging out from the nerve cord itself. These paired peripheral nerves always have elaborate end-arborizations on the medial surface of the lateral muscle cells. They are accordingly interpreted as motor axons. Some thinner peripheral nerve fibres originate at irregular intervals from both the nerve cord and the ganglion cells. Due to the numerous extracellular fibrils that connect the bilateral layers of the epidermal fins and the muscle cells to each other, these thin nerve fibres can seldom be traced to their termination. A few ones can, however, be traced ventrally between the notochord and the muscle cells and seem to end in singular bulb-like expansions. Clusters of synaptic vesicles are present in transmission electron micrographs of such nerves, and they are accordingly believed to carry efferent impulses. The extracellular fibrils are arranged in a highly ordered pattern with thick bundles crossing the gap between the structures to be interconnected and with numerous radiating insertions on the surface of the tissues.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00223014
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  • 13
    Electronic Resource
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    The Surface structure of isolated pancreatic islet cells (1975)
    Springer
    Cell & tissue research 164 (1975), S. 467-471 
    Details
    ISSN: 1432-0878
    Keywords: Pancreas ; Islets ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The surfaces of isolated pancreatic islet cells were studied with the scanning and transmission electron microscopes. Islets were isolated from the pancreas of Wistar rats by collagenase treatment and were incubated either in glucose-free medium or in 300 mg% glucose for one hour. Immunoreactive insulin (IRI) in the media of both control and experimental preparations was assayed. Islets were then transferred to 4% glutaraldehyde, buffered with cacodylate, pH 7.4, and prepared for scanning and transmission electron microscopy. Cell masses average 200 μ in diameter. Alpha cells appear pyramidal in shape, are about 8 μ in diameter and appear in groups. Beta cells are round or oval in shape and have an average diameter of 10 μ. Glucose stimulation raised the IRI value tenfold and increased the number of blebs and other surface irregularities per unit area of beta cell surface. Comparison with transmission electron micrographs suggests that the blebs are related to the process of emiocytosis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00219938
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  • 14
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    A scanning electron microscopic study of rabbit spermatozoa in the female reproductive tract following coitus (1975)
    Springer
    Cell & tissue research 163 (1975), S. 29-44 
    Details
    ISSN: 1432-0878
    Keywords: Spermatozoa ; Capacitation ; Uterus ; Acrosome Reaction ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The surface morphology of rabbit spermatozoa, fixed in situ (female reproductive tract) and prepared for scanning electron microscopy by critical point drying, was studied for as many as 36 hours post coitum. The findings demonstrate that 1) spermatozoa in the reproductive tract following coitus exist as a heterogenous, morphological population and 2) with time, shifts within this population from one predominant morphology to another take place. In the fresh ejaculate, most spermatozoa have intact surfaces free of membranous disruptions. With time, a process of labilization (denudation) of the membranes covering the acrosomal region occurs in a progressively larger proportion of spermatozoa. The labilization originates by a process of vesiculation and/or vacuolation and leads to the appearance of a series of small fenestrations or perforations of the surface membranes. The perforations coalesce, and gradually larger areas of the surface membranes are eroded such that by 15 hours post coitum, the outer acrosomal membrane, as well as other acrosomal areas, are to varying degrees, directly exposed to the uterine milieu. Secretory granules, picked up by cilia and transferred to the spermatozoa become localized over the acrosomal region shortly after coitus. The possible significance of these time-dependent, morphological events with the phenomena of capacitation and the “true” and “false” acrosome reactions are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00218589
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  • 15
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    The reality of arthropod cuticular laminae (1975)
    Springer
    Cell & tissue research 163 (1975), S. 411-413 
    Details
    ISSN: 1432-0878
    Keywords: Cuticle ; Laminae ; Arthropod ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Examination of etched pyramids of decapod crustacean cuticles with the scanning electron microscope indicates that laminae are continuous around the angles of the pyramids. This observation is in direct contrast to the result expected on Bouligand's (1965, 1971) hypothesis and suggests that laminae may be real structures.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00219475
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  • 16
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    Pantolacton aus Coenzym A. Bestimmung von Pantothensäure (1975)
    Springer
    Fresenius' Zeitschrift für analytische Chemie 277 (1975), S. 124-124 
    Details
    ISSN: 1618-2650
    Keywords: Pantothensäure, Pantolacton ; Chromatographie, Gas ; Hydrolyse von Coenzym A
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00602082
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  • 17
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    Ermittlung des Vernetzungsgrades und Beladungszustandes von Ionenaustauschern auf Kunstharzbasis durch Pyrolyse-Gas-Chromatographie (1975)
    Springer
    Fresenius' Zeitschrift für analytische Chemie 277 (1975), S. 9-17 
    Details
    ISSN: 1618-2650
    Keywords: Ermittlung des Vernetzungsgrades, Beladungszustandes von Ionenaustauschern ; Chromatographie, Gas ; Pyrolyse, Kunstharzbasis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Zur besseren Reproduzierbarkeit der Zusammensetzung des Pyrolysates bei der Pyrolyse-Gas-Chromatographie wird eine spezielle Eingabenanordnung mit Trägergasumschaltung beschrieben und deren Einfluß auf die Bildung der Pyrolyseprodukte und auf die Retentionszeiten mit einer Modellsubstanz untersucht. Mit Hilfe der Trägergasumschaltung kann man die Bandenflächenverhältnisse zur Bestimmung des Vernetzungsgrades von Ionenaustauschern auf Styrol-DVB-Basis wesentlich genauer ermitteln. Da bei der Pyrolyse von Anionenaustauschern wenigerα-MSt auftritt als bei den Kationenaustauschern, sind die Bandenflächenverhältnisse bei ersteren wesentlich größer. Bei den Anionenaustauschern werden sie mit steigendem Vernetzungsgrad kleiner, wohingegen bei den Kationenaustauschern die Werte steigen. Bei 400° C erfolgt der thermische Angriff im wesentlichen an der aktiven Gruppe der Anionenaustauscher mit Styrol-DVB-Matrix. Die aus dem Gegenion entstehenden Methylester bzw. deren Zersetzungsprodukte sind charakteristische Pyrolyseprodukte. Kennzeichnend für Dowex 1 ist das Auftreten von Trimethylamin, für Dowex 2 das von Acetaldehyd. Somit ist es mit der Pyrolyse-Gas-Chromatographie möglich, zusätzlich zur Matrix, Art und Struktur der funktionellen Gruppe sowie Substitutionsstelle der Ankergruppen an der Matrix auch Vernetzungsgrad und Beladungszustand von Ionenaustauschern zu ermitteln.
    Notes: Abstract A special introduction device with switching of carrier gas for improving the reproducibility of pyrolysate composition in pyrolysis gas-chromatography has been described. Its influence on the formation of pyrolysis products and on retention times has been studied on a model substance. The peak area ratios for determining the degree of cross-linking in ion exchangers on styrene-DVB basis can be estimated considerably more accurately with the help of carrier gas switching. Since anion exchangers yield lessα-methylstyrene on pyrolysis than do cation exchangers, their peak area ratios are appreciably larger. Increasing the degree of cross-linking lowers the ratios with the anion exchangers and raises them with the cation exchangers. At 400° C the thermal attack on anion exchangers with styrene-DVB matrix occurs mainly at the active group. The methyl esters or their decomposition products formed from the counter ions are characteristic pyrolysis products. A feature of Dowex 1 is the formation of trimethylamine; of Dowex 2, acetaldehyde. In this way, pyrolysis gas-chromatography enables information about the degree of cross linking and the nature of the anion of ion exchangers, as well as about the matrix, type and structure of the functional group and position of substitution of the anchor group in the matrix to be obtained.
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    URL: http://dx.doi.org/10.1007/BF00591870
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  • 18
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    Ultrapolare Mischphasen zur GLC-Bestimmung von Benzol (1975)
    Springer
    Fresenius' Zeitschrift für analytische Chemie 277 (1975), S. 31-32 
    Details
    ISSN: 1618-2650
    Keywords: Best. von Benzol ; Chromatographie, Gas ; ultrapolare Mischphasen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00591874
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  • 19
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    Zur Analytik von Organozinnstabilisatoren (1975)
    Springer
    Fresenius' Zeitschrift für analytische Chemie 273 (1975), S. 19-23 
    Details
    ISSN: 1618-2650
    Keywords: Analyse von Organozinnverbindungen, Alkylzinnverbindungen, Organozinnstabilisatoren ; Chromatographie, Gas
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Die quantitative Bestimmung von Mono-, Di-, Tri- und Tetraalkylzinnverbindungen in Mischungen durch Gas-Chromatographie ist möglich nach Alkylierung zu gemischten Tetraalkylzinnderivaten. Die Alkylierung mit Methyl-, Butyl- und Octylmagnesylchlorid in Diäthyläther ist quantitativ und verläuft ohne Veränderung der ursprünglichen Zinnverteilung. Sie läßt sich nicht nur auf Alkylzinnoxide und -chloride, sondern auch direkt auf Alkylzinn-thioglykolate anwenden. Die aus der Umsetzung der Thioglykolsäureester resultierenden Nebenprodukte werden von der gas-chromatographischen Analyse an Kieselgel absorbiert und die Tetraalkylzinnverbindungen mit n-Pentan eluiert. Die gas-chromatographische Trennung wird wahlweise an Carbowax oder Polyglycol 20000 durchgeführt bei Temperaturen zwischen 100 und 230° C. Die Peak-Flächen entsprechen den Gew.-% Tetraalkylzinn.
    Notes: Abstract The quantitative determination of mono-, di-, tri- and tetraalkyl tin compounds in mixture by GLC is possible after alkylation to mixed tetraalkyl tins. The alkylation with methyl-, butyl- and octyl magnesium chloride runs quantitatively without any change in the original alkyl groups attached to the tin. The method can be applied not only for alkyl tin oxides and chlorides but also directly for alkyl tin thioglycolates. The by-products resulting from the thioglycolic acid ester cleavage are absorbed on silica gel prior to GLC and the tetraalkyl tins are eluted with n-pentane. Gas-chromatographic analysis is carried out alternatively with carbowax and polyglycol 20000 at temperatures between 100 and 230° C. The peak areas correspond to the weight percentage of tetraalkyl tin.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00459399
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  • 20
    Electronic Resource
    Electronic Resource
    Gas-chromatographische Überwachung des Extraktionsmittels bei der Wiederaufarbeitung von HTR-Brennelementen (1975)
    Springer
    Fresenius' Zeitschrift für analytische Chemie 273 (1975), S. 113-116 
    Details
    ISSN: 1618-2650
    Keywords: Best. von Monobutylphosphat, Dibutylphosphat in Tributylphosphat, n-Alkanen ; Chromatographie, Gas ; Überwachung der Wiederaufarbeitung von HTR-Brennelementen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Bei der Wiederaufarbeitung von HTR-Brennelementen durch Solventextraktion nach dem THOREX-Prozeß wird das als Extraktionsmittel verwendete Tributylphosphat/n-Alkan-Gemisch einer intensiven hydrolytischen und radiolytischen Beanspruchung ausgesetzt. Hauptprodukte sind Di- und Monobutylphosphat, die schon in geringen Konzentrationen durch Bildung nicht rückextrahierbarer Urankomplexe und Überführung gewisser Spaltprodukte in die wäßrige Produktphase zu Störungen bei der Extraktion führen. Beide Ester werden durch Sodawäsche aus dem bestrahlten Extraktionsmittel entfernt, welches danach wiederverwendet werden kann. Zur Kontrolle der Wirksamkeit dieser Solventwäsche, der Zusammensetzung des frischen und der Gesamtqualität des recyclierten Extraktionsmittels soll die Gas-Chromatographie innerhalb des JUPITER-Prozesses eingesetzt werden. Sie erlaubt eine quantitative Bestimmung von DBP und MBP bis zu Gehalten von etwa 25 ppm. Die Analysendauer beträgt ca. 100 min.
    Notes: Abstract During reprocessing of HTR fuel elements by the THOREX solvent extraction process the tributylphosphate/n-alcane mixture used as extractant is subject to an intensive radiolytic and hydrolytic burden. Main degradation products are di- and monobutylphosphate which in quite low concentrations disturb the solvent extraction by retention of uranium and transfer of some fission products into the aqueous product solution. Both esters are removed from the irradiated solvent by washing with a sodium carbonate solution, after which the solvent may be recycled. For a control of the efficiency of this solvent recovery procedure as well as of the composition of the fresh and recycled solvent in the JUPITER reprocessing facility, gas chromatography will be used. This method allows the determination of di- and monobutylphosphate down to concentration levels of about 25 parts per million. An analysis requires about 100 min.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00426269
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  • 21
    Electronic Resource
    Electronic Resource
    Gas chromatography of chlorides and bromides of III-, IV- and V-group elements in the periodic table (1975)
    Springer
    Fresenius' Zeitschrift für analytische Chemie 274 (1975), S. 353-357 
    Details
    ISSN: 1618-2650
    Keywords: Analyse von Chloriden, Bromiden ; Chromatographie, Gas ; Elemente der III. -V. Gruppe
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Summary The theory for the relation between retention volume and boiling point in gas chromatography was applied to the retention volumes for bromides of IV- and chlorides and bromides of III- and V-group elements in the periodic table, as an extension of the previous paper on chlorides of IV-group elements. The apparent solubility parameter of solventβδ S was separated into the non-regularity parameterβ and the solubility parameter of solventδ S, and the meaning ofβ and the value ofδ S were estimated empirically. Followingδ S values were obtained: Silicon oil DC 550 (8.1), Apiezon grease L (9.1), PEG 1500 (11.6), FeCl3 · 6 H2O (12.5), Low melting point alloy (12.5) and Ga metal (13.4).
    Notes: Zusammenfassung Die Theorie über die Beziehung zwischen Retentionsvolumen und Siedepunkt in der Gas-Chromatographie wurde auf die Retentionsvolumina der Bromide der IV. sowie der Chloride und Bromide der III. und V. Gruppe angewendet (in Fortführung der früheren Arbeit über die Chloride der IV. Gruppe). Der scheinbare Löslichkeitsparameter des Lösungsmittels (βδ S) wurde aufgetrennt in den Unregelmäßigkeitsparameter (β) und den Löslichkeitsparameter des Lösungsmittels (δ S). Die Bedeutung vonβ und der Wert vonδ S wurden empirisch bestimmt. Die folgendenδ S-Werte wurden erhalten: Siliconöl DC 550 (8,1), Apiezonfett L (9,1), PEG 1500 (11,6), FeCl3 · 6 H2O (12,5), niedrigschmelzende Legierung (12,5), Ga-Metall (13,4).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00626033
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  • 22
    Electronic Resource
    Electronic Resource
    Gas-chromatographische Bestimmung von monosubstituierten Acetylenen in der C4-Fraktion (1975)
    Springer
    Fresenius' Zeitschrift für analytische Chemie 275 (1975), S. 27-27 
    Details
    ISSN: 1618-2650
    Keywords: Best. von Acetylen, Methylacetylen, Äthylacetylen, Vinylacetylen ; Chromatographie, Gas ; Isolierung als Acetylide
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00432994
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  • 23
    Electronic Resource
    Electronic Resource
    Notiz über eine gas-chromatographische Bestimmung von Essigsäure und Propionsäure in Polyamid 6 (1975)
    Springer
    Fresenius' Zeitschrift für analytische Chemie 276 (1975), S. 127-128 
    Details
    ISSN: 1618-2650
    Keywords: Best. von Essigsäure und Propionsäure in Polyamid 6 ; Chromatographie, Gas
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01165816
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  • 24
    Electronic Resource
    Electronic Resource
    3-Hydroxyglutarsäuredinitril als Trennflüssigkeit für die GLC (1975)
    Springer
    Fresenius' Zeitschrift für analytische Chemie 277 (1975), S. 373-373 
    Details
    ISSN: 1618-2650
    Keywords: Verw. von 3-Hydroxyglutarsäuredinitril als Trennflüssigkeit ; Chromatographie, Gas
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00423783
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