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  • 1
    Electronic Resource
    Electronic Resource
    The Origin and Bifurcation of the Space-Time Defects in the Early Universe (1997)
    Springer
    General relativity and gravitation 29 (1997), S. 715-725 
    Details
    ISSN: 1572-9532
    Keywords: RIEMANN-CARTAN SPACE-TIME ; TORSION ; DISLOCATION
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract In the early universe, a new topological invariant is interpreted as the space-time dislocation flux and is quantized in the topological level. By extending to a topological current of dislocations, the dynamic form of the defects is obtained under the condition that the Jacobian determinant D(φ/u) ≠ 0. When D(φ/u) = 0, it is shown that there exists the crucial case of branch process. Based on the implicit function theorem and the Taylor expansion, the origin and bifurcation of the space-time dislocations are detailed in the neighborhoods of the limit points and bifurcation points of φ-mapping, respectively. It is pointed out that, since the dislocation current is identically conserved, the total topological quantum numbers of the branched dislocation fluxes will remain constant during their origin and bifurcation processes, which are important in the early universe because of spontaneous symmetry breaking.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1018881821774
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  • 2
    Electronic Resource
    Electronic Resource
    Hydrogenation of aldehydes and ketones catalyzed by a polysulfosiloxane-platinum complex (1994)
    New York, NY : Wiley-Blackwell
    Polymers for Advanced Technologies 5 (1994), S. 606-608 
    Details
    ISSN: 1042-7147
    Keywords: Hydrogenation ; Aldehydes ; Ketones ; Polysulfosiloxane-supported ; Platinum complex ; 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
    Notes: An acidic inorganic polymer, polysulfosiloxane, has been prepared and used as ligand for preparing a polysulfosiloxane-platinum complex. It has been found that such a complex could catalyze the hydrogenation of aldehydes and ketones to alcohols, giving as much as 100% yield at room temperature and under atmospheric pressure. Temperature, S/Pt molar ratio in the complex and solvents greatly influenced the reaction. This complex was very stable and could be used several times without any change in catalytic activity.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pat.1994.220050925
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    Paper (German National Licenses)
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