ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 30 (1986), S. 821-830 
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The total (elastic plus inelastic) intensities of 51 keV electrons scattered by water molecules have been measured over a range of 1 ≦ K = (4π/λ) sin(θ/2) ≦ 12 Å-1. A computer program, ELIC, has been written for calculating the total intensities of electrons scattered by free molecules. The intensities can be calculated with self-consistent field and configuration interaction wavefunctions. The theoretical intensities based on a CI wavefunction are in good agreement with the observed intensities.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: 3-Methyl-2-isopropenyl-2-oxazolinium salts (4a, b) were prepared by alkylation of 2-isopropenyl-2-oxazoline (2). Their preparation is much easier than that of their vinyl analogues, 3-methyl-2-vinyl-2-oxazolinium salts, which cannot be isolated due to their high tendency to polymerization. 4a, however, was found, to show a low tendency toward radical and anionic polymerization, but it can be smoothly radically copolymerized with some vinyl monomers. The copolymerization parameters of 4a were determined and discussed in comparison with those of 2.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 176 (1975), S. 2225-2239 
    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: Die Chelatbildung der Vinylamin/Vinylalkohol-Copolymeren mit Kupfer(II)ionen wurde sowohl spektrophotometrisch als auch titrimetrisch untersucht. Zum Vergleich wurden weiterhin Gemische aus Polyvinylamin und Polyvinylalkohol vermessen. Es ergab sich, daß die Kupfer(II)ionen im Falle der Copolymersysteme ausschließlich von den Stickstoffatomen des Copolymerliganden koordiniert werden. Die Komplexierungskonstanten der Chelate wurden durch Anwendung der modifizierten Bjerrumschen Methode - unter Vernachlässigung der Säuredissoziation der Copolymer-Hydroxygruppen - bestimmt. Es ergab sich. daß die Copolymer/Kupfer(II)chelate mit abnehmendem Gehalt an NH2-Gruppen in den Copolymeren instabiler werden. Im Falle der Homopolymer-Gemische werden die Kupfer(II)ionen nur von den Stickstoffatomen des Polyvinylamins, nicht aber von den Sauerstoffatomen des Polyvinylalkohols koordiniert.
    Notes: Chelate formation of vinylamine/vinyl alcohol copolymers with copper(II) was studied both by the spectrophotometric and by titrimetric methods. For comparison, polyvinylamine/poly(vinyl alcohol) mixtures were also taken up for measurements. In the case of the copolymer systems, copper(II) ions were found to be coordinated exclusively by nitrogen atoms of the copolymer ligand. The complexation constants of the chelates were determined by applying the modified Bjerrum method, in neglect of the acid dissociation of hydroxy groups in the copolymers. It was found that the copolymer/Cu(II) chelates tend to be unstable with decreasing contents of NH2 groups in the copolymers. In the homopolymer mixture systems, copper(II) ions are not coordinated by the oxygen atoms of poly(vinyl alcohol), but only by the nitrogen atoms of polyvinylamine.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 176 (1975), S. 3425-3431 
    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: Verdünnungsenthalpien für Poly(1-vinyl-2-pyrrolidon), (Poly[1-(2-oxopyrrolidin-1-yl)-ethylene]), in wäßrigen Methanollösungen von unterschiedlichem Methanolgehalt, wurden bei 298 K gemessen. Das Molekulargewicht des Polymeren betrug 10000 bzw. 40000.Die experimentellen Ergebnisse wurden nach einer modifizierten Tompa-Gleichung mit konzentrationsabhängigem Wechselwirkungsparameter analysiert und so der Wechselwirkungsparameter zwischen dem Polymeren und dem Mischlösungsmittel für unendliche Verdünnung erhalten.Der Einfluß von Methanol auf die Wechselwirkung zwischen dem Polymeren und Wasser wurde aufgrund der Änderungen des Wechselwirkungsparameters bei unendlicher Verdünnung für die Überführung des Polymeren von Wasser in wäßriges Methanol diskutiert.
    Notes: Enthalpies of dilution of poly(1-vinyl-2-pyrrolidone), (poly[1-(2-oxopyrrolidin-1-yl)ethylene]), in aqueous methanol solutions of different methanol contents were measured at 298 K. The molecular weight of the polymer was 10000 and 40000, respectively.The experimental results were analysed with a modified Tompa formula containing an interaction parameter dependent on concentration; so the interaction parameter at infinite dilution between the polymer and the mixed solvent was derived.The influence of methanol on the interaction between polymer and water molecules was discussed from the change of the interaction parameter at infinite dilution for the transfer process from water to aqueous methanol solvent.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 176 (1975), S. 2241-2249 
    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: Die durch verschiedene Kupfer(II)chelate in Gegenwart von Tetrachlormethan initiierte Polymerisation von Acrylnitril (AN) und Methylmethacrylat (MMA) wurde untersucht. Als polymere Liganden wurden sowohl einige Vinylamin (VAm)/Vinylalkohol (VA)-Copolymerisate verschiedener Gehalte an Monomereinheiten mit NH2- und OH-Gruppen als auch einige Polyvinylamin (PVAm)/Polyvinylalkohol (PVA)-Gemische (gleicher Gehalte an NH2- und OH-Gruppen wie die entsprechenden Copolymeren) sowie PVAm und PVA verwendet. Die Aktivität dieser polymeren Chelate zur Auslösung der AN und der MMA Polymerisation bei verschiedenen pH-Werten der Reaktionssysteme wurde verglichen. Im Falle der Polymerisation von MMA, zeigten die VAm/VA-Copolymersysteme eine höhere Aktivität als das PVAm-Chelat mit der gleichen molaren Konzentration an NH2-Gruppen, im Gegensatz zur AN-Polymerisation bei der die Polymerisationsaktivität ein umgekehrtes Verhalten zeigte. Der Initiierungsmechanismus wird diskutiert.
    Notes: The polymerization of acrylonitrile (AN) and of methyl methacrylate (MMA) initiated by various copper(II) chelates was studied in the presence of carbon tetrachloride. Several vinylamine (VAm)/vinyl alcohol (VA) copolymers with different contents of NH2 and OH bearing monomeric units were chosen as polymer ligands as well as polyvinylamine (PVAm)/poly(vinyl alcohol) (PVA) mixtures (of equal NH2 and OH group contents as the corresponding copolymers), PVAm, and PVA. The activity of the used polymer chelates to initiate the AN and the MMA polymerization was compared at various pH values of the reaction systems. For the polymerization of MMA, the VAm/VA copolymer systems showed a higher activity than the PVAm chelate containing the same amount of NH2 groups, contrary to the case of the polymerization of AN, where the polymerization activity showed a reverse behavior. The initiation mechanism is discussed.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 176 (1975), S. 1945-1951 
    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: Die Darstellung und Charakterisierung von Benzyl-2-(methacryloyloxy)äthylhydrogen-phosphat (8) werden beschrieben. Das Monomere wurde in Gegenwart von 2,2′-Azoisobutyronitril (AIBN) zu Poly{1-[2-(benzylhydrogenphosphato)äthyloxycarbonyl]äthylen}, (9) polymerisiert, dessen Eigenschaften ebenfalls beschrieben werden.
    Notes: The preparation and characterization of benzyl 2-(methacryloyloxy)ethyl hydrogen phosphate (8) are described. This monomer was polymerized in the presence of 2,2′-azoisobutyronitrile (AIBN) to give poly{1-[2-(benzylhydrogenphosphato)ethyloxycarbonyl]-ethylene}, (9), whose properties are also described.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 24 (1986), S. 1161-1171 
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The relationship between chemical structure and low-temperature modulus of ultraviolet(UV)-radiation-cured optical-fiber coating materials has been investigated. The coating materials are low-viscosity liquid compounds consisting of a 1,4-polybutadiene diacrylate oli-gomer, a monomer, and a photoinitiator. Dynamic mechanical test results show that low-temperature modulus and glass transition temperature (Tg) are affected by the monomer structure and monomer concentration in the coating material in cases where the same oligomer is used. With increasing alkyl group chain length of the alkylacrylate monomer, the Tg value is shifted to lower temperatures. Low-temperature modulus increases with increasing monomer concentration in the coating material. Low-temperature excess optical losses of coated fibers have been found to be closely related to low-temperature modulus of the coating.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Biotechnology and Bioengineering 28 (1986), S. 1707-1712 
    ISSN: 0006-3592
    Keywords: Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Chondroitinase ABC catalyzing the depolymerization of chondroitin sulfate was induced by incubating the Proteus vulgaris cells in a medium containing chondroitin C sulfate as an inducer. Incubation of P. vulgaris cells for 12 h in the presence of 0.3% inducer was optimal to obtain the cells with highly active chondroitinase ABC. Such cells were immobilized in k-carrageenan gel lattice, and some properties of chondroitinase ABC in immobilized cells were studied in comparison with those of the enzyme without immobilization (free enzyme). The stabilities of the enzyme toward heat and storage were remarkably improved by immobilizing the cells in k-carrageenan gel lattice. Optimal pH and temperature for activity of the enzyme were slightly shifted to the alkaline region and higher temperature by immobilization and were 9.0 and 35°C, respectively.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    ISSN: 0003-3146
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Die radikalisch durch verschiedene α,ω-Diaminoalkan-Kupfer(II)-Komplexe initiierte Polymerisation von Acrylnitril wurde in Dimethylsulfoxidlösung untersucht. Es ergab sich, daß stabile Komplexe, wie der Äthylendiamin-Kupfer(II)-Komplex, die Polymerisation fast nicht auslösen, während die instabilen Komplexe von 1,5-Diaminopentan, 1,6-Diaminohexan und n-Butylamin die Polymerisation gut auslösen konnten.Die Polymerisationsauslösung wurde ferner spektrophotometrisch untersucht. Die Reduktion der Kupfer(II)-Komplexe zu Kupfer(I)-Komplexen während der Polymerisation wurde durch sichtbare Spektroskopie sowie die Kuproin-Färbungsmethode bestätigt. Die Reduktionsgeschwindigkeit steht eng mit der Stabilität der Diamin-Kupfer(II)-Komplexe in Beziehung. Aus den Ergebnissen wird der Initiierungsmechanismus diskutiert.
    Notes: Free radical polymerization of acrylonitrile initiated by various α,ω-diaminoalkane-copper(II) complexes was studied in dimethyl sulfoxide solution. It was found that the stable copper(II) complexes, like ethylenediamine copper(II) complex, could hardly initiate the polymerization, while the unstable copper(II) complexes, such as 1,5-diaminopentane, 1,6-diaminohexane and n-butylamine complexes could initiate the polymerization.Initiation was further studied spectrophotometrically. Reduction of the copper(II) to the copper(I) complexes was ascertained to occur during the polymerization by visible spectroscopy and cuproin coloration method. The rate of reduction was related closely to the stability of the diamine-copper(II) complexes. From the results the initiation mechanism was discussed.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 32 (1986), S. 4573-4580 
    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: Nylon-3 prepared by hydrogen transfer polymerization of acrylic amide was N-methoxymethylated by paraformaldehyde/methanol in its formic acid solution. This product was soluble in water, and we were able to obtain a transparent membrane by casting of the solution. Absorbance of the NH group on IR spectrum was decreased by methoxymethylation, and from this depression of absorbance a degree of N-methoxymethylation of about 33% was obtained which agreed with the value from elemental analysis. DSC curve of this polymer showed a endothermic peak at 80°C which was assumed to be the Tg and a exothermic peak starting at 180°C which was assumed to be the crosslinking reaction. The degree of crystalinity of this polymer was about 40% which was obtained by deuterium exchange reaction with deuterium oxide. By heating of this polymer membrane up to 190°C, it was changed to an insoluble polymer by the crosslinkage reaction between methoxymethyle and unreacted amide groups. This insoluble polymer membrane was used for the separation of water/alcohol mixture by the pervaporation technique. Through the membrane, water was permeated selectively compared with alcohol and the selective permeation was found to increase by raising the heat treatment temperature.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...