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  • 1
    Electronic Resource
    Electronic Resource
    Polyimide structure-property relationships. III. Polyimides from multi-ring diamines (1981)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 26 (1981), S. 3805-3817 
    Details
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: The effects of increasing the distance between, and varying the isomeric positions of, the amine groups on the glass transition temperatures of aromatic polyimides were studied in order to investigate routes to improve processability. A number of isomers of three- and four-ring benzenoid diamine systems were polymerized with 3,3′,4,4′-benzophenone tetracarboxylic acid dianhydride to poly(amic acids), which were converted to polyimides. The use of methylene and carbonyl groups to connect the benzene rings of the diamines, and in one case the dianhydride, afforded a comparison of the thermomechanical properties of the polyimides to those prepared from diphenylmethane- and benzophenone-diamines, respectively. Generally, the dilution of the imide content by the insertion of benzylene and benzoylene segments into the diamines significantly reduced the glass transition temperatures, with the benzylene group being more effective in that respect than the benzoylene. However, there was evidence that the position isomerism (ortho, meta, para) of the amine groups was more influential in affecting the glass transition temperatures of aromatic polyimides than was the dilution of the imide content.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1981.070261127
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  • 2
    Electronic Resource
    Electronic Resource
    The rate of acid removal by liquid ion exchangers (1963)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 9 (1963), S. 857-860 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690090627
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  • 3
    Electronic Resource
    Electronic Resource
    Vapor condensation in the mixing zone of a jet (1964)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 10 (1964), S. 115-124 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Experimental studies were made of fog formation in free jets containing glycerine and dibutyl phthalate. Visual and photographic observations showed that condensation took place near the nozzle in the mixing zone between the jet and the ambient air. Fog formation began at a well-defined location downstream from the nozzle depending on the initial velocity, temperature, and concentration of vapor. The location could be changed by inserting solid bodies or by adding foreign nuclei to the mixing zone. Measurements were made of mean temperature and concentration profiles in the mixing zone with noncondensable gases. These compared well with the predictions of turbulent boundary-layer theory. Calculations were made of the supersaturation to be expected in the case of glycerine. Downstream of the point where condensation first occurred fog filled most of the region where the calculated supersaturation was above unity. Based on the experimental evidence a mechanism is proposed for condensation in a free jet.
    Additional Material: 21 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690100132
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  • 4
    Electronic Resource
    Electronic Resource
    Die Pyridinaddukte der Goldhalogenide. 3. Darstellung, Eigenschaften und Kristallstruktur zweier Modifikationen von AuBr · NC5H5 (1984)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 512 (1984), S. 169-176 
    Details
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Pyridine Adducts of Gold Halides. 3. Preparation, Properties, and Crystal Structure of Two Modifications of AuBr · NC5H5The reaction of AuBr · S(CH2C6H5)2 with pyridine in absolute ethanol yields the crystalline compound AuBr · pyridine. It crystallizes in the triclinic space group P1 with the lattice constants a = 791.5(2) pm, b = 935.6(2) pm, c = 1005.1(3) pm, α = 85.78(2)°, β = 102.07(2)°, γ = 109.31(2)°. When the solvent is toluene, monoclinic crystals are formed with the space group C2/c and a = 1225.9(2) pm, b = 1522.2(3) pm, c = 1459.7(3) pm, β = 97.82(2)°. The triclinic structure is built up by Au4 zig-zag chains AuBr2 - Au(py)2 - Au(py)2 - AuBr2, whereas the monoclinic phase contains infinite chains with the sequence AuBr2 - Au(py)2. In each case the linkage is formed by weak Au - Au-interactions.
    Notes: Bei der Umsetzung von AuBr · S(CH2C6H5)2 mit Pyridin in absolutem Ethanol kristallisiert AuBr · Pyridin in Form trikliner Kristalle mit der Raumgruppe P1 und den Gitterkonstanten a = 791,5(2) pm, b = 935,6(2) pm, c = 1005,1(3) pm, α = 85,78(2)°, β = 102,07(2)°, γ = 109,31(2)°. Wird die Reaktion dagegen in absolutem Toluol durchgeführt, so erhält man eine monokline Modifikation mit der Raumgruppe C2/c und a = 1225,9(2) pm, b = 1522,2(3) pm, c = 1459,7(3) pm, ß = 97,82(2)°. Die Strukturen beider Modifikationen bestehen aus linearen Au(py)2- und AuBr2-Gruppen, die durch schwache Gold-Gold-Wechselwirkungen zu kettenförmigen Komplexen verbunden sind. Die trikline Modifikation bildet diskrete Au4-Zickzack-Ketten AuBr2 - Au(py)2 - Au(py)2 - AuBr2. In der monoklinen Phase sind die Baugruppen in der Abfolge AuBr2 - Au(py)2 zu unendlichen Ketten verknüpft.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19845120518
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  • 5
    Electronic Resource
    Electronic Resource
    Polyspirane, 91). Umlagerungskaskaden, 41). Über die Verwendbarkeit von Polyspiranen zum Eintritt in Polycyclen-Hyperflächen - Fünf- bzw. neunfache 1,2-Verschiebungen an einem Pentaspiro[3.0.2.0.3.0.2.0.3.1]nonadecan (1984)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 117 (1984), S. 3075-3092 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Polyspiranes, 91). Cascade Rearrangements, 41). On the Usefulness of Polyspiranes for Entering Energy Surfaces of Polycyclic System - Five- and Ninefold 1,2-Shifts in a Pentaspiro[3.0.2.0.3.0.2.0.3.1]nonadecaneAcid-catalyzed rearrangements of the pentaspirane 7b yield either the propellane 13 or the hexacyclic compound 14, depending on the reaction conditions. The structures and conformations of 13 and 14 were determined by crystal structure analyses of their derivatives 22 and 16 and 18, respectively. The rearrangements 7b→13 and 7b→14 proceed diastereospecifically and are rationalized as five- and ninefold 1,2-shifts, respectively.
    Notes: Sauer katalysierte Umlagerungen des Pentaspirans 7b liefern in Abhängigkeit von den Reaktionsbedingungen das Propellan 13 oder den Hexacyclus 14. Struktur und Konformation von 13 und 14 wurden über Kristallstrukturanalysen ihrer Derivate 22 bzw. 16 und 18 bestimmt. Die Umlagerungen 7b→13 und 7b→14 verlaufen diastereospezifisch und können als fünf- bzw. neunfache 1,2-Verschiebungen aufgefaßt werden.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19841171008
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  • 6
    Electronic Resource
    Electronic Resource
    Cyclisierung von (Fluorsilyl)phosphanen zu 1,3-Diphospha-2,4-disilacyclobutanen - Kristallstrukturuntersuchungen (1983)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 116 (1983), S. 146-151 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Cyclisation of (Fluorsilyl)phosphanes to 1,3-Diphospha-2,4-disilacyclobutanes - Crystal Structure DeterminationsLithiated tert-butylphosphane reacts with di-tert-butyldifluorosilane and with difluorobis[methyl(trimethylsilyl)amino]silane to give the (fluorosilyl)phosphanes 1 and 2 as well as the (di-tert-butylsilanediyl)bisphosphane 3. The cyclic compounds 4 and 5 are obtained in the reaction of 1 and 2 with tert-C4H9Li. Dilithiated 3 reacts with dichlorophenylphosphane to form the 1,2,3-triphospha-4-silacyclobutane 6. According to crystal structure analyses, 4 and 5 contain planar Si2P2 rings with Si—P bonds between 224.1(1) and 228.0(1) pm.
    Notes: Lithiiertes tert-Butylphosphan reagiert mit Di-tert-butyldifluorsilan und Difluorbis[methyl(trimethylsilyl)amino]silan zu den (Fluorsilyl)phosphanen 1 und 2 sowie zum (Di-tert-butylsilandiyl)-bisphosphan 3. Die cyclischen Verbindungen 4 und 5 werden durch die Umsetzung von 1 und 2 mit tert-C4H9Li erhalten. Dilithiiertes 3 reagiert mit Dichlorphenylphosphan zum 1,2,3-Triphospha-4-silacyclobutan 6. Nach Kristallstrukturanalysen besitzen 4 und 5 jeweils planare Si2P2-Ringe mit Si—P-Bindungen zwischen 224.1(1) und 228.0(1) pm.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19831160117
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  • 7
    Electronic Resource
    Electronic Resource
    4-Chlor-1,2,3,5-dithiadiazolium-Salze (1983)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 116 (1983), S. 416-423 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: 4-Chloro-1,2,3,5-dithiadiazolium SaltsThe synthesis of 4-chloro-1,2,3,5-dithiadiazolium chloride (9) from SCI2 and either N-cyanosulfur difluoride imide (8) or bis(trimethylsilyl)carbodiimide (12) is described. The analogous dibromide 13 is formed from S2Br2 and 8. The ionic chlorine in 9 may easily be exchanged with the help of silver salts, acids, and Lewis acids yielding ClCN2S2+A- (9a-d, A- = AsF6-, SbCl6-. ½SnCl62-, SO3-). The crystal structure of the hexafluoroarsenate 9a has been determined.
    Notes: Die Synthese von 4-Chlor-1,2,3,5-dithiadiazolium-chlorid (9) aus N-Cyanoschwefeldifluoridimid (8) bzw. aus Bis(trimethylsilyl)carbodiimid (12) und SCI2 wird beschrieben. Das zu 9 analoge Dibromid 13 entsteht aus 8 und S2Br2. Mit Hilfe von Silbersalzen, Säuren und Lewis-Säuren läßt sich das ionisch gebundene Chlor in 9 leicht austauschen unter Bildung von CICN2S2+A- (9a-d, A- = AsF6-, SbCl6-, ½SnCl62-, SO3F-). An dem Hexafluoroarsenat 9a wurde eine Kristallstrukturbestimmung durchgeführt.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19831160203
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  • 8
    Electronic Resource
    Electronic Resource
    Umsetzungen von Metall- und Metalloidverbindungen mit mehrfunktionellen Molekülen, XXXVIII. Reaktion von Ethandiamiden mit Bromdimethylboran (1984)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 117 (1984), S. 2112-2131 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reactions of Metal and Metalloid Compounds with Polyfunctional Molecules, XXXVIII. The Reaction of Ethanediamides with BromodimethylboraneReactions of symmetrically substituted N,N′-dialkyl-(diaryl)ethanediamides A with bromodimethylborane are investigated. Reactions in the molar ratio of 1 : 2 yield the 2,6-dioxonia-4,8-diaza-3,7-diboratabicyclo[3.3.0]octanes 1a - j, the N,N′-bis(dimethylboryl)-N,N′-diorganylethanediamides 4a, b, and the equilibrium mixtures 3a - d. By-products are 2-oxonia-4-oxa-6-azonia-8-aza-3,7-diboratabicyclo[3.3.0]octanes 2a - j. By the reaction of N,N′-diorganylethanediamides with bromodimethylborane in the molar ratio 1 : 1 the 1-oxonia-3-aza-2-boratacyclopentan-4-one derivatives 5a - e, N-(dimethylboryl)-N,N′-diorganylethanediamides 6a - c, the equilibrium mixtures 7a - d, and the 5-(alkylamino)-4-(alkylimonio)-2,2-dimethyl-1-oxonia-3-oxa-2-boratacyclopentane bromides 8a - h are obtained. X-ray analyses have been carried out for 1a, 5a, e and 8b.
    Notes: Es werden Reaktionen symmetrisch substituierter N,N′-Dialkyl-(Diaryl)ethandiamide A mit Bromdimethylboran untersucht. Die Reaktion im Molverhältnis 1 : 2 führt zu 2,6-Dioxonia-4,8-diaza-3,7-diboratabicyclo[3.3.0]octanen 1a - j, N,N′-Bis(dimethylboryl)-N,N′-diorganylethandiamiden 4a, b und den Gleichgewichtsmischungen 3a - d. Als Nebenprodukte treten 2-Oxonia-4-oxa-6-azonia-8-aza-3,7-diboratabicyclo[3.3.0]octane 2a - j auf. Bei der Umsetzung von N,N′-Diorganylethandiamiden mit Bromdimethylboran im Molverhältnis 1 : 1 erhält man die 1-Oxonia-3-aza-2-boratacyclopentan-4-on-Derivate 5a - e, N-(Dimethylboryl)-N,N′-diorganylethandiamide 6a - c, Gleichgewichtsmischungen 7a - d und 5-(Alkylamino)-4-(alkylimonio)-2,2-dimethyl-1-oxonia-3-oxa-2-boratacyclopenta n-bromide 8a - h. Für 1a, 5a, e und 8 b wurden Röntgenstrukturanalysen durchgeführt.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19841170609
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  • 9
    Electronic Resource
    Electronic Resource
    (Disilylamino)phosphane (Rf)2P - N(SiMe3)2 - Bausteine für PN3S2-Ringe (1984)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 117 (1984), S. 1583-1590 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: (Disilylamino)phosphanes (Rf)2P - N(SiMe3)2 - Precursors for PN3S2 RingsThe reactions of the (disilylamino)phosphanes (Rf)2P - N(SiMe3)2 (Rf = CF3, C2F5) with S3N2Cl2 lead to new cyclophosphadithiatriazenes of composition (Rf)2PN3S2 (1a, b) with elimination of Me3SiCl and S8. By-products are (Rf)2P(Cl) = NSiMe3 (2a, b). Reaction of 1a, b with norbornadiene yields 1:1 adducts 3a, b. The X-ray structure analysis of 3a (Rf = CF3) is reported. When 1a is allowed to stand for several days a crystalline compound of composition [(CF3)2PN2S]2 (4) is formed. The X-ray structure analysis shows that 4 contains an eight-membered ring with 1,3-P(CF3)2 groups.
    Notes: Aus den (Disilylamino)phosphanen (Rf)2P - N(SiMe3)2 (Rf = CF3, C2F5) und S3N2Cl2 werden unter Abspaltung von Me3SiCl und S8 neue Cyclophosphadithiatriazene der Zusammensetzung (Rf)2PN3S2 (1a, b) erhalten. Als Nebenprodukte treten Phosphanimide (Rf)2P(Cl) = NSiMe3 (2a, b) auf. 1a, b bilden mit Norbornadien 1:1-Addukte 3a, b. Die Röntgenstrukturanalyse von 3a (Rf = CF3) wird mitgeteilt. Aus 1a bildet sich nach mehrtägigem Stehenlassen eine kristalline Verbindung [(CF3)2PN2S]2 (4), deren Röntgenstrukturbestimmung einen achtgliedrigen Ring mit 1,3-P(CF3)2-Gruppen zeigt.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19841170426
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  • 10
    Electronic Resource
    Electronic Resource
    Stufenweise Synthese ketten- und ringförmiger Siloxane  -  Kristallstrukturen (1984)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 117 (1984), S. 2988-2997 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Stepwise Synthesis of Chain and Ring Siloxanes  -  Crystal StructuresDisilanols of the type R2Si(OH)2 (1, 2: R = CHMe2, CMe3) and the fluorosilanol (Me3 C)2Si(OH)F (3) serve as starting materials in the reaction with halosilanes for the stepwise construction of chain siloxanes (4 - 15, 16 - 20). Even siloxanes with bulky tert-butyl or silylamino groups are easily prepared (10, 16, 17, 20). Crystalline silanediols (2, 14, 19) are connected in chains (19) or dimeric rings (2, 14) by hydrogen bonding. The 1,3-difluoro- (18), 1,3-dihydroxy- (19), and 1-fluoro-3-hydroxydisiloxane 6 as well as the cyclotrisiloxane 21 were isolated from the reaction of F2Si(CHMe2)2 with potassium hydroxide. Directed synthesis of Si  -  O six-membered rings (21 - 24) is possible via reaction of 1,3-dihydroxydisiloxanes 19, 20 with di- and trihalosilanes. The crystal structures of 2, 14, and 24 are discussed.
    Notes: Disilanole des Typs R2Si(OH)2 (1, 2: R = CHMe2, CMe3) und das Fluorsilanol (Me3C)2Si(OH)F (3) dienen in Reaktionen mit Halogensilanen als Startmaterial zum stufenweisen Aufbau von kettenförmigen Siloxanen (4 - 15, 16 -20). Auch Siloxane mit voluminösen tert-Butyl- oder Silylaminogruppen sind leicht zugänglich (10, 16, 17, 20). Kristalline Silandiole (2, 14, 19) sind über Wasserstoff-Brückenbindungen ketten- (19) oder dimer-ringförmig (2, 14) verknüpft. Aus der Reaktion von F2Si(CHMe2)2 mit Kaliumhydroxid wurde das 1,3-Difluor- (18), 1,3-Dihydroxy (19), 1-Fluor-3-hydroxydisiloxan 6 sowie da Cyclotrisiloxan 21 isoliert. Die Si  -  O-Sechsringe 21 - 24 können gezielt aus den 1,3-Dihydroxydisiloxanen 19, 20 mit Di- und Trihalogensilanen erhalten werden. Die Kristallstrukturen von 2, 14 und 24 werden diskutiert.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19841170916
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