ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

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
  • 1
    Electronic Resource
    Electronic Resource
    31P- und 195Pt-NMR-Untersuchungen an Diplatin(I)-Komplexen des Typs [Pt2(μ-SPR2)2L2] (L = PR3, PhP(OPh)2, P(OPh)3, CNR)VIII. Mitteilung aus der Reihe Sekundäre Phosphinochalkogenide; VII. Mitteilung s. (1983)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 504 (1983), S. 117-127 
    Details
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: 31P and 195Pt N.M.R. Investigations on Diplatinum (I) Complexes of the Type [Pt2(μ-SPR2)2L2] (L = PR3, PhP(OPh)2, P(OPh)3, CNR)31P-, 195Pt-chemical shifts and 195Pt-31P- resp. 31P-31P-coupling constants of a series of doubly bridged diplatinum(I) complexes are reported. 31P-coordination chemical shifts of the terminal ligands of complexes of type [Pt2(μ-SPR2)2(P′R3′)2] and some of the various coupling constants are strongly influenced by the π-acceptor strength of these ligands. J(195Pt-195Pt) is found to change the sign among the series of complexes investigated. Thermal singlett triplet exitation giving rise to the paramagnetism of these complexes observed by preliminary EPR-measurements and confirmed by EHT-calculations is deduced from the large values of 2J(P-P′) and 3J(P′P′) as well as the unusually high temperature dependence of some coupling constants and other NMR features. The chemical stability of the doubly bridged core, the coordination shifts of the bridging phosphorus atoms and EHT-calculations suggest a view of aromaticity of the [Pt2(μ-SPR2)2](M-M) unit of these complexes.
    Notes: Es werden 31P-, 195Pt-chemische Verschiebungen und 195Pt31P-Kopplungskonstanten einer Reihe von doppelt verbrückten Diplatin(I)-Komplexen mitgeteilt. 31P-koordinationschemische Verschiebungen der ternären Liganden von Komplexen des Typs [Pt2(μ-SPR2)2(P′R3′)2] und verschiedene Kopplungskonstanten werden stark von der π-Akzeptor-Stärke dieser Liganden beeinflußt. J(195P-195Pt) wird innerhalb der Reihe der untersuchten Komplexe mit wechselndem Vorzeichen gefunden. Aus den großen Werten von 2J(Pt-P′) und 3J(P′P′) sowie der ungewöhnlich starken Temperaturabhängigkeit einiger Kopplungskonstanten und anderen NMR-Eigenschaften wird auf Paramagnetismus dieser Komplexe aufgrund thermischer Singlett-Triplett-Anregung geschlossen, der in vorläufigen EPR-Messungen gefunden und durch EHT-Rechnungen gestützt wird. Die chemische Stabilität des doppelt verbrückten Kerns, die koordinationschemischen Verschiebungen der Brückenphosphoratome und EHT-Rechnungen weisen auf Aromatizität der [Pt2(μ-SPR2)2](M-M)-Einheit dieser Komplexe hin.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19835040915
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Mechanical degradation of mica during processing with polypropylene (1984)
    Brookfield, Conn. : Wiley-Blackwell
    Polymer Composites 5 (1984), S. 264-276 
    Details
    ISSN: 0272-8397
    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
    Notes: Mechanical degradation of reinforcing fillers during processing is a problem that has been seldom studied due to a lack of particle size determination techniques. Using phlogopite mica as an example, a method allowing a rapid and accurate characterization of flake size and aspect ratio will be described. The influence of several parameters on the mechanical degradation of mica flakes in a mica/polypropylene system has been studied using a laboratory roller blade mixer. The degradation was found to occur in two stages. The first stage takes place immediately after the addition of mica, where the average flake size decreases very rapidly by as much as 20 percent. In the second stage, the particle size remains essentially constant with the time of mixing at low concentrations (2 percent wt); at higher concentrations (40 percent wt) there is a slow reduction in the flake size. The influence of other parameters such as system viscosity, mode of mica addition, silane treatment, and the initial particle size is also discussed.
    Additional Material: 21 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pc.750050406
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Factors affecting the surface texture in extruded mica-polypropylene composites (1984)
    Brookfield, Conn. : Wiley-Blackwell
    Polymer Composites 5 (1984), S. 299-306 
    Details
    ISSN: 0272-8397
    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
    Notes: A Taylor-Hobson Talysurf instrument was used to quantify the surface roughness of phlogopite mica-polypropylene extrudates. The rate of feeding and the speed of rotation of the screw were found to have a significant effect on the surface texture. Under the appropriate conditions of extrusion the roughness of 40 percent (by weight) mica-filled polypropylene extrudates could be reduced by a factor of three. This effect was found to be independent of the extrusion rate.
    Additional Material: 13 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pc.750050409
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Investigation on the formation of polychlorophosphazene branchings at different units of the polymer chain (in Russian) (1980)
    Weinheim : Wiley-Blackwell
    Acta Polymerica 31 (1980), S. 568-571 
    Details
    ISSN: 0323-7648
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Considering the presence of amido and imido end groups the side reactions resulting in the formation of branched macromolecules of polychlorophosphazenes in thermal polymerization in the melt are discussed. The effect of residual water and the amount of HCl in the polymerization system, the filling degree of the polymerization vessel and the polymerization time at 250°C on the chemical inhomogeneity of the polychlorophosphazenes obtained was investigated. By changing these conditions the formation of chemically inhomogeneous branched macromolecules can be controlled.
    Notes: Ausgehend von der Anwesenheit von Amido- und Imidoendgruppen im Polychlorphosphazen werden die Nebenreaktionen erörtert, die zur Bildung verzweigter Makromoleküle bei der thermischen Schmelzepolymerisation führen. Es wurde der Einfluß solcher Faktoren wie Restwasser im Polymerisationssystem, HCl-Menge, Grad der Ampullenfüllung und Polymerisationszeit bei 250°C auf die chemische Uneinheitlichkeit des gebildeten Polychlorphosphazens untersucht. Es wurde gezeigt, daß eine Änderung dieser Bedingungen eine bewußte Steuerung der Bildung verzweigter chemisch uneinheitlicher Makromoleküle ermöglicht.
    Additional Material: 6 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/actp.1980.010310907
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Cationic polymerization of lactones in the presence of hydroxyl-containing compounds (1983)
    Weinheim : Wiley-Blackwell
    Acta Polymerica 34 (1983), S. 754-761 
    Details
    ISSN: 0323-7648
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Der Mechanismus der kationischen Polymerisation von Lactonen in Gegenwart hydroxylhaltiger Verbindungen (Hydroxomechanismus) wurde am Beispiel der Polymerisation von β-Propiolacton, ε-Caprolacton, Glycolid und Lactid untersucht. Bei diesem Mechanismus erfolgt das Kettenwachstum über eine vorhergehende Kettenübertragung auf das Monomer. Diese Übertragungsreaktion beschleunigt den Prozeß, verringert die rel. Molekülmasse des Polymers, verschmälert die Molekülmassenverteilung und erhöht die allgemeine Stabilität des Systems.
    Notes: The mechanism of cationic polymerization of lactones in the presence of hydroxyl-containing compounds (hydroxomechanism) has been studied taking as an example the polymerization of β-propiolactone, ε-caprolactone, glycolide and lactide. In this mechanism chain propagation proceeds via preliminary chain transfer to the monomer. This transfer accelerates the process, decreases the molecular weight of the polymer, narrows the molecular-mass distribution and enhances the general stability of the system.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/actp.1983.010341118
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Quasielastic neutron scattering study of dynamics at the crossover from dilute to semidilute behavior in polymer solutions (1982)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Letters Edition 20 (1982), S. 233-240 
    Details
    ISSN: 0360-6384
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1982.130200405
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Raman and infrared spectra of solid carbon diselenide (1983)
    Chichester [u.a.] : Wiley-Blackwell
    Journal of Raman Spectroscopy 14 (1983), S. 96-98 
    Details
    ISSN: 0377-0486
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Raman and infrared spectra of polycrystalline samples of CSe2 have been recorded at temperatures from 20-205 K. A comparison with previous results for CS2 shows that the spectra are consistent with the two substances having the same centrosymmetric orthorhombic structure. The observed spectra for CSe2, in both the lattice and molecular regions, are in good agreement with group theoretical predictions based on this structure. There is only one solid phase over the range of temperatures examined.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jrs.1250140208
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Effect of chemical inhomogeneities of polychlorophosphazenes on the synthesis and properties of polyorganophosphazenes (1980)
    Weinheim : Wiley-Blackwell
    Acta Polymerica 31 (1980), S. 669-672 
    Details
    ISSN: 0323-7648
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: With the polymer-analogous substitution of the chlorine atoms in polychlorophosphazenes (PCP) by trifluoroethoxy groups as an example, the chemical inhomogeneity of the initial PCP, caused by branching of the macromolecules, was found to affect considerably the degree of conversion, the solubility and the thermal properties of the polyorganophosphazene being formed.
    Notes: Am Beispiel der polymeranalogen Substitution der Chloratome im Polychlorphosphazen (PCP) durch Trifluorethoxygruppen wurde gezeigt, daß die chemische Uneinheitlichkeit des Ausgangs-PCP, bedingt durch die Verzweigung seiner Makromoleküle, den Umsatzgrad, die Löslichkeit und die thermomechanischen Eigenschaften des entstehenden Polyorganophosphazens beträchtlich beeinflußt.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/actp.1980.010311101
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Comparison of dynamically coated SE-54, SP-2250 and carbowax 20M wall-coated open tubular (WCOT) glass capillary columns, prepared after surface pretreatment with Superox™-4 or with BaCO3 (1980)
    Weinheim : Wiley-Blackwell
    Journal of High Resolution Chromatography 3 (1980), S. 115-123 
    Details
    ISSN: 0935-6304
    Keywords: Gas chromatography ; Capillary, glass ; Preparation of deactivated capillaries for routine analysis ; Easy deactivation and pretreatment steps described in detail ; Comparison of different modes given ; Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A new surface pretreatment for the preparation of wall-coated open tubular (WCOT) glass capillary columns has been evaluated. This technique involves the application of a non-extractable layer of Superox™-4, a 4,000,000 MW polyethylene glycol, to the glass surface as a pretreatment and deactivation agent. Unlike other polyethylene glycols, Superox-4 is stable at high temperatures (〉 300°C) in the absence of oxygen, coats smoothly onto a bare glass surface and resists droplet formation. WCOT columns (SE-54, Carbowax 20M, and SP-2250) prepared using this technique are compared to columns prepared using a modified Grob [2,3] BaCO3 procedure. The Superox-4 pretreated columns were equal or superior in quality to the BaCO3 pretreated columns, based on the appearance of an activity standard and the effective theoretical plates (Neff) per meter. Chromatograms showing practical application of the WCOT columns prepared using both methods is given.
    Additional Material: 12 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jhrc.1240030303
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Mass spectrometry of 2-substituted 5-nitro-2-furyl thiazoles. Identification of microsomal nitroreduction products by electron impact mass spectrometry (1981)
    Chichester : Wiley-Blackwell
    Biological Mass Spectrometry 8 (1981), S. 305-311 
    Details
    ISSN: 1052-9306
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The electron impact mass spectral fragmentation of nitro heterocyclic carcinogens N-[4-(5-nitro-2-furyl)-2-thiazolyl]formamide, 2-amino-4-(5-nitro-2-furyl)thiazole, 2-methyl-4-(5-nitro-2-furyl)thiazole and 2-methylamino-4-(5-nitro-2-furyl)thiazole were studied. The molecular ions undergo two modes of cleavage: one giving [M-84]+ ions which include the 2-substituted thiazole ring, while the other gives rise to the fragment [M-74]+ ions. The products of anaerobic microsomal nitroreduction of 2-methyl-4-(5-nitro-2-furyl)thiazole were isolated and purified by high-pressure liquid chromatography. The metabolites undergo different fragmentation patterns compared to the parent nitro analogs. Metabolites from anaerobic enzymatic reduction showed identical gas chromatographic, high-pressure liquid chromatographic and thin-layer chromatographic properties to the chemically synthesized material. The metabolites were identified as 1-(2-methyl-4-thiazolyl)-3-cyano-1-propenone and 1-(2-methyl-4-thiazolyl)-3-cyano-1-propanone by mass spectral fragmentation pattern.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bms.1200080705
    Location Call Number Expected 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...