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  • Quantum information  (3)
  • Polymer and Materials Science  (2)
  • Cytoplasmic inheritance Double fertilization  (1)
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Sexual plant reproduction 7 (1994), S. 313-323 
    ISSN: 1432-2145
    Keywords: Cytoplasmic inheritance Double fertilization ; Embryo sac Mitochondrial transmission ; Tobacco ; Sperm cell
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Serially sectioned embryo sacs of Nicotiana tabacum were examined during fertilization events using transmission electron microscopy. After pollen tube discharge, the outer membrane of the sperm pair is removed, the two sperm cells are deposited in the degenerate synergid and the sperm cells migrate to the chalazal edge of the synergid where gametic fusion occurs. During fertilization, the male cytoplasm, including heritable organelles, is transmitted into the female reproductive cells as shown by: (1) the cytoplasmic confluence of one sperm and the central cell during cellular fusion, (2) the occurrence of sperm mitochondria (distinguished by ultrastructural differences) in the zygote cytoplasm and adjacent to the sperm nucleus, (3) the presence of darkly stained aggregates which are found exclusively in mature sperm cells within the cytoplasm of both female cells soon after cell fusion, and (4) the absence of any large enucleated cytoplasmic bodies containing recognizable organelles outside the zygote or endosperm cells. The infrequent occurrence of plastids in the sperm and the transmission of sperm cytoplasm into the egg during double fertilization provide the cytological basis for occasional biparental plastid inheritance as reported previously in tobacco. Although sperm mitochondria are transmitted into the egg/zygote, their inheritance has not been detected genetically. In one abnormal embryo sac, a pair of sperm cells was released into the cytoplasm of the presumptive zygote. Although pollen tube discharge usually removes the inner pollen-tube plasma membrane containing the two sperm cells, this did not occur in this case. When sperm cells are deposited in a degenerating synergid or outside of a cell, this outer membrane is removed, as it apparently is for fertilization.
    Type of Medium: Electronic Resource
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  • 2
    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: Das Kristallisationsverhalten von Polyetheretherketon (PEEK) wurde mit Hilfe der Differentialkalorimetrie (DSC) untersucht. Mit der Erhöhung der Kristallinität verschiebt sich die Glastemperatur zu höheren Temperaturen. Hitzebehandeltes PEEK zeigt Doppelpeaks in der DSC-Kurve, was für PEEK charakteristisch ist. Diese Doppelpeaks werden, je nach den Bedingungen der Hitzebehandlung, durch die Bildung unvollständiger Kristallstrukturen hervorgerufen.
    Notes: The crystallization behavior of polyetheretherketone (PEEK) was investigated by differential scanning calorimetry (DSC). The glass transition temperature of PEEK shifts to higher temperatures with an increase in crystallinity. Heat-treated PEEK showed double peaks in their DSC curves, which is a characteristic phenomenon of PEEK. These double peaks were caused by the formation of incomplete crystal structures according to the conditions of heat-treatment.
    Additional Material: 13 Ill.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Polymers for Advanced Technologies 7 (1996), S. 79-83 
    ISSN: 1042-7147
    Keywords: hydrogenation ; m-xylene ; polysilazane ; stereochemistry ; 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: A new kind of inorganic polymer, silica-supported polysilazane (Si-N), and its platinum complex (Si-N-Pt) were prepared and characterized by X-ray photoelectron spectroscopy. It was found that Si-N-Pt can catalyze hydrogenation of m-xylene under mild conditions (30-50°C, 1 atm). The products of the reaction were cis- and trans-1,3-dimethylcyclohexane. The formation of trans-1,3-dimethylcyclohexane may be adequately explained according to the “roll-over” model. The stereoselectivity was influenced by temperature and catalyst concentration, the proportion of the cis isomer decreasing with an increase in each of the two factors. The effects of other reaction parameters, such as the N/Pt mole ratio in the complex, solvents and reaction time, etc., on the hydrogenation of m-xylene were also studied. The Si-N-Pt catalyst is very stable in reaction and turnover numbers amount to 520 in 70 hr.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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  • 4
    Publication Date: 2012-01-11
    Description: Author(s): Fang-Yu Hong, Yang Xiang, W. H. Tang, Zhi-Yan Zhu, Li-zhen Jiang, and Liang-neng Wu [Phys. Rev. A 85, 012309] Published Tue Jan 10, 2012
    Keywords: Quantum information
    Print ISSN: 1050-2947
    Electronic ISSN: 1094-1622
    Topics: Physics
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  • 5
    Publication Date: 2012-07-26
    Description: Author(s): Fang-Yu Hong, Yang Xiang, Zhi-Yan Zhu, Li-zhen Jiang, and Liang-neng Wu A “bucket brigade” architecture for a quantum random memory of N =2 n memory cells needs n ( n +5)/2 times of quantum manipulation on control circuit nodes per memory call. Here we propose a scheme in which only on average n /2 times manipulations are required to accomplish a memory call. This scheme may ... [Phys. Rev. A 86, 010306] Published Wed Jul 25, 2012
    Keywords: Quantum information
    Print ISSN: 1050-2947
    Electronic ISSN: 1094-1622
    Topics: Physics
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  • 6
    Publication Date: 2013-03-30
    Description: Author(s): Fang-Yu Hong, Huiqin Qian, Jing-Li Fu, Zhi-Yan Zhu, and Li-zhen Jiang We describe a scheme that enables a strong coherent coupling between a topological qubit and the quantized motion of a magnetized nanomechanical resonator. This coupling is achieved by attaching an array of magnetic tips to a namomechanical resonator under a quantum phase controller which coherently... [Phys. Rev. A 87, 032339] Published Fri Mar 29, 2013
    Keywords: Quantum information
    Print ISSN: 1050-2947
    Electronic ISSN: 1094-1622
    Topics: Physics
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