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  • 1
    Electronic Resource
    Electronic Resource
    Photophysical properties and laser performance of photostable UV laser dyes (1988)
    Springer
    Applied physics 45 (1988), S. 279-284 
    Details
    ISSN: 1432-0649
    Keywords: 07.65 ; 33 ; 42.55 ; 82.50
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract The photophysical properties such as singlet absorption and fluorescence spectra, the fluorescence quantum yield and fluorescence decay time as well as the laser performance data such as the tuning range, the conversion efficiency, and the photochemical stability of 12 sterically hinderedp-quaterphenyls have been measured in ethanol and/or dioxane at room temperature. The sterically hinderedp-quaterphenyls exhibit shorter laser dye emissions in the 330–380 nm range than the parent compoundp-quaterphenyl. The conversion efficiencies of the sterically hinderedp-quaterphenyls range between 1 and 21%. The photochemical stability of the sterically hinderedp-quaterphenyls is by a factor of 10 to 20 better in dioxane than in ethanol. 2-Methyl-5-tert. butyl-p-quaterphenyl and 2,5,2‴,5‴-tetramethyl-p-quaterphenyl are among the most stable UV laser dyes known today.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00687157
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  • 2
    Electronic Resource
    Electronic Resource
    The effect of systemic treatment with 5-fluorouracil on the epidermis of the guinea pig (1978)
    Springer
    Archives of dermatological research 263 (1978), S. 31-35 
    Details
    ISSN: 1432-069X
    Keywords: 5-Fluorouracil ; 3H thymidine labelling index ; Mitoses in the epidermis ; Atrophy of the epidermis ; S-phase ; 5-Fluorouracil ; 3H-Thymidin-Labelling-Index ; Mitosen in der Epidermis ; Atrophisierung der Epidermis ; DNS-Synthesezeit
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Vor und während einer Behandlung mit 5-Fluorouracil (1 mg i.p. in 2tägigem Abstand/100 g KG) wurde beim Meerschweinchen der 3H-Thymidin-Labelling-Index in der Basalschicht der Epidermis bestimmt. Parallel wurde die Zahl der in der Metaphase blockierbaren Mitosen in der Epidermis mit der Colcemidmethode ermittelt. Außerdem wurden Epidermisfläche, Epidermisdicke, Zellzahl in der Epidermis und Zellgröße in der Epidermis analysiert. 5-Fluorouracil reduziert den 3H-Thymidin-Labelling-Index und die Mitoserate bei der Colcemidmethode in der gleichen Weise, wobei der Effekt erst nach einer Behandlungszeit von mehr als 22 Tagen voll zum Tragen kommt. Die Parallelität dieser Befunde läßt annehmen, daß die DNS-Synthesezeit nicht wesentlich verändert wird, wenn man sie vom Zeitpunkt der Thymidin-Synthese an rechnet. Zeitlich parallel kommt es außerdem zu einer Atrophisierung der Epidermis.
    Notes: Summary The thymidine labelling index and the mitosis rate (blocked by colcemid) in the basal cell layer of the guinea pig were determined before and during treatment with 5-fluorouracil (1 mg i.p. in 2 day's interval/100 g body weight). Additionally, the epidermal area and thickness and the number and size of cells were measured. 5-Fluorouracil equally reduces the thymidine labelling index and the mitosis rate with the full effect after treatment of at least 22 days. From these findings it is concluded that the S-phase — calculated from the end of the thymidine synthesis — is not altered. Furthermore atrophy of the epidermis runs parallel with the reduction of the 3H thymidine labelling index and the mitosis rate.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00446851
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  • 3
    Electronic Resource
    Electronic Resource
    Über die synthese methylsubstituierter oligophenylene mit einer m-verknüpfung. 9. Mitteilung1 (1960)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 40 (1960), S. 189-199 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: For the synthesis of angular oligophenylenes, cyclohexandione(1,3) and ethylmonoenolic-ether of cyclohexandione(1,3) are reported. A new synthesis of this enolic-ether is described.A suggested nomenclature for the oligophenylenes possessing a complicated structure is also given.The following methyl-substituted oligophenylenes with one meta-linkage have been synthesized: 32,43-dimethyl-2m3-quaterphenyl;12,23-dimethyl-3m3-quinquiphenyl;12,23,42,53-tetramethyl-3m3-quinquiphenyl and12,23,42,63-tetramethyl-3m3-sexiphenyl.The products are readily soluble and have low melting points.
    Notes: Zur Synthese von gewinkelten Oligophenylenen werden Cyclohexandion(1,3) und der Athylmonoenoläther des Cyclohexandion(1,3) verwendet. Eine neue Synthese dieses Enolthers wird beschrieben.Es wird ein Nomenklaturvorschlag zur Bezeichnung von Oligophenylenen komplizierter Struktur gegeben.Die folgenden methylsubstituierten Oligophenylene mit einer m-Verknüpfung wurden dargestellt: 32,43-Dimethyl-2m3-quaterphenyl;12,23-Dimethyl-3m3-quinquiphenyl;12,23,42,53-Tetramethyl-3m3-quinquiphenyl und12,23,42,63-Tetramethyl-3m3-sexiphenyl.Die Verbindungen sind gut lösliche, niedrig schmelzende Substanzen.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1960.020400117
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  • 4
    Electronic Resource
    Electronic Resource
    Über die Darstellung und Polymerisation von 4-Vinyldiphenyl, 11-Vinyl-p-terphenyl und 1 2-Vinyl-p-terphenyl (1969)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 126 (1969), S. 73-86 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: The synthesis of 4-vinylbiphenyl and 11-vinyl-p-terphenyl was performed by a simple synthetic route. By reaction of the corresponding alcohols with methanesulfonyl chloride in pyridine the vinyl compounds could be prepared by a one step reaction.Investigation of the radical copolymerisation of the monomers with styrene showed a favoured incorporation of 4-vinylbiphenyl and 12-vinyl-p-terphenyl into the polymer chain in contrast to the behaviour of 11-vinyl-p-terphenyl.
    Notes: Für die Darstellung von 4-Vinyldiphenyl und 11-Vinyl-p-terphenyl wurden einfache, verallgemeinerungsfähige Synthesen ausgearbeitet. Durch Umsetzung entsprechender Carbinole mit Methansulfonsäurechlorid in Pyridin gelang die Darstellung der Vinylverbindungen in einer einstufigen Reaktion.Die Untersuchung der radikalischen Copolymerization der Monomeren mit Styrol ergab bei 4-Vinyldiphenyl und 12-Vinyl-p-terphenyl einen bevorzugten Einbau in die Polymerketten, während 11-Vinyl-p-terphenyl nur in untergeordnetem Maße in Polystyrolketten eingebaut wurde.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1969.021260110
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  • 5
    Electronic Resource
    Electronic Resource
    Über die synthese methylsubstituierter p-oligophenylene. 7. Mitteilung (1960)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 37 (1960), S. 198-216 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: The synthesis of methyl-substituted p-oligophenylenes up to a degree of condensation of 8 is reported.The preparation of the starting materials is thoroughly discussed. The synthesis is carried out according to previous described methods, to the ULLMANN-reaction and to the organo-metallic-carbonyl-reaction.
    Notes: Es wird über die Synthese methylsubstituierter p-Oligophenylene bis zum Kondensationsgrad 8 berichtet.Die Darstellung der dafür benötigten Ausgangsprodukte wird ausführlich behandelt. Die Synthese wird nach früher beschriebenen Verfahren, der ULLMANN-Reaktion und der Metallorgano-Carbonyl-Reaktion, durchgeführt.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1960.020370120
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  • 6
    Electronic Resource
    Electronic Resource
    Über die Synthese methylsubstituierter P-Oligopenylene. 5. Mitteilung4. Mitt: W. KERN, R. GEHM und M. SEIBEL, Makromolekulare Chem. 15 (1955) 170.WERNER KUHN zum 60. Geburtstag gewidmet (1959)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 29 (1959), S. 164-189 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Unsubstituted p-oligophenylenes are very sparingly soulble. The solubility of these substances can be increased by substituting methyol groups.Different methods were investigated for the synthesis of methyl-substituted p-oligophenylenes.Thus, through ULLMANN condensation of the corresponding iodo-aryls two isomeric substituted tetramethyl-p-quaterphenyls, one tetramethoxy-p-quaterphenyl and one tetramethyl-p-sexiphenyl were synthesized.By taking the advantage of carbonyl addition of aromatic metallic compounds on cyclic diketones - with hydroaromatics as the intermediate step in the reaction - one dimethyl-p-ter- phenyl, one tetramethyl-p-quinquiphenyl, two isomeric substituted tetramethyl-p- quaterphenyls, and one tetramethyl-p-sexiphenyl were obtained.Further, with the N-nitroso-aacetylarylamin-reaction the synthesis of another diemethyl-p-quaterphenyl was achieved.Electrophilic substitution-reactions were studied on the dimethyl-p-terphenyl. It was observed that the substituents chiefly go to the p-position.For the nomenclature of these compounds a new scheme of enumeration is proposed and used.The methyl-substituted p-oligophenylenes show have distinctly different solubility characteristics when compared with unsubstituted base substances. The solubility may thus increse to a high power of ten.
    Notes: Unsubstituierte p-Oligophenylene sind sehr schwer löslich. Die Löslichkeit dieser substanzen kann durch Substitution mit Methylgruppen verbessert werden.Für die Synthese methylsubstituierter p-Oligophenylence wurden verschiedene Verfahren herangezogen.Durch ULIMANN-Kondensation entsprechender Jodaryle konnten zwei substitutionsisomere Tettamethyl-p-quaterphenyle, ein Tetramethoxy-p-quaterphenyl und ein Tetramethyl-p-sexiphenyl synthetisiert werden.Über die Carbonyladdition aromatischer metallorganischer Verbindungen an cyclische Diketone wurden über hydroaromatische Zwischenstufen ein Dimethyl-p-terphenyl, ein Tetramethyl-p- quinquiphenul, zwei substitutionsisomere Dimethyl-p-quaterphenyle und ein Tetramethyl-p-sexiphenyl erhalten.Mit der N-Nitroso-acetylarylamin-Reaktion gelang die Synthese eines weiteren Dimethyl-p-quaterpyenyls.An dem Dimethyl-p-terphenyl wurden elektrophile Substitutionsreaktionen studiert. Dabei ergab sich, daß die Substituenten bevorzugt die p-Stellung aufsuchen.Die Bencnnung dieser Verbindungen wird nach einem neuen Bezifferungs-Schema vorgenommen.Methylsubstituierte p-Oligophenylene besitzen gegenüber den unsubstituierten Grundkörpern ausgeprägte LoUslichkeitseigenschaften. Der Löslichkeitsunterschied kann mehrere Zehnerpotenzen ausmachen.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1959.020290115
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  • 7
    Electronic Resource
    Electronic Resource
    Zur Kenntnis der Orthosalze von Sauerstoffsäuren. II. Natriumargentit (1951)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 265 (1951), S. 220-228 
    Details
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Es existieren zwei Natriumargentite: 3Na2O · Ag2O und 2Na2O · Ag2O. Ersteres ist bei 300° bei Anwesenheit von Sauerstoff instabil; es wird Natriumoxyd als Peroxyd abgespalten und die Verbindung geht in die zweitgenannte, stabile über. Chemisch verhalten sich beide Argentite so wie ihre oxydischen Bestandteile.Für die Gewinnung Für die Gewinnung des Natriumargentits war reines Natriumoxyd notwendig. Seine Herstellung auf einem besonderen Wege wird beschrieben.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19512650406
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  • 8
    Electronic Resource
    Electronic Resource
    The effect of organotin chlorides on the thermal stability of PVC (1979)
    Brookfield, Conn. : Wiley-Blackwell
    Journal of Vinyl and Additive Technology 1 (1979), S. 51-54 
    Details
    ISSN: 0193-7197
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Metal chlorides formed from metal stabilizers under processing conditions have an influence on the thermal stability of PVC. Zinc chloride, e. g., has a strong destabilizing effect, whereas lead chloride behaves almost indifferently. Alkyltin chlorides however, have a stabilizing effect in as much as they cause a significant retardation of the thermal dehydrochlorination rate of PVC. Using 1-chlorobutene-2 as model substance, a chloro allyl isomerization could be proved caused by organotin chlorides under certain conditions. These results support a complex chemical isomerization concept to explain the stabilizing effect of organotin chlorides on PVC.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/vnl.730010112
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