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991.
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994.
V. I. Bespalov V. I. Bredichin D. G. Efimov B. I. Katsman B. Králiková L. Láska K. Mašek K. Rohlena J. Skála S. A. Sukharev P. Trenda I. N. Voronich A. I. Zareckij 《Czechoslovak Journal of Physics》1995,45(9):761-765
The frequency tripling of the iodine laser PERUN is described. The maximum conversion efficiency to the third harmonic is 50%, which represents about 20 J of the 3 laser beam. 相似文献
995.
E. Kröner 《International Journal of Theoretical Physics》1990,29(11):1219-1237
Since line defects (dislocations) and point defects (vacancies, self-interstitials, point stacking faults) in Bravais crystals can mutually convert, only theories which comprise these two sorts of defects can be closed in the sense of general field theory. Since the pioneering work of Kondo and of Bilby, Bullough, and Smith it is clear that differential geometry is the appropriate mathematical tool to formulate a field theory of defects in ordered structures. This is done here on the example of the Bravais crystal, where the above-mentioned defects are the only elementary point and line defects. It is shown that point defects can be described by a step-counting procedure which makes it possible to include also point stacking faults as elementary point defects. The results comprise two equations with the appropriate interpretation of the mathematical symbols. The point defects are step-counting defects and are essentially described by a metric tensorg, which supplements the torsion responsible for the dislocations. The proposed theory is meant to form a framework for defect phenomena, in a similar way that Maxwell's theory is a framework for the electromagnetic world. 相似文献
996.
997.
Marsiske H Antreasyan D Bartels HW Besset D Bieler C Bienlein JK Bizzeti A Bloom ED Brock I Brockmüller K Cabenda R Cartacci A Cavalli-Sforza M Clare R Compagnucci A Conforto G Cooper S Cowan R Coyne D Engler A Fairfield K Folger G Fridman A Gaiser D Gelphman D Glaser G Godfrey G Graaf K Heimlich FH Heinsius FH Hofstadter R Irion J Jakubowski Z Janssen H Karch K Keh S Kiel T Kilian H Kirkbride I Kloiber T Kobel M Koch W König AC Königsmann K Kraemer RW Krüger S Landi G Lee R Leffler S 《Physical review D: Particles and fields》1990,41(11):3324-3335
998.
Werner O Wågberg L Lindström T 《Langmuir : the ACS journal of surfaces and colloids》2005,21(26):12235-12243
Super-hydrophobic surfaces may arise due to an interplay between the intrinsic, relatively high, contact angle of the more or less hydrophobic solid surface employed and the geometric features of the solid surface. In the present work, this relationship was investigated for a range of different surface geometries, making use of surface free energy minimization. As a rule, the free energy minima (and maxima) occur when the Laplace and Young conditions are simultaneously fulfilled. Special effort has been devoted to investigating the free energy barriers present between the Cassie-Baxter (heterogeneous wetting) and Wenzel (homogeneous wetting) modes. The predictions made on the basis of the model calculations compare favorably with experimental results presented in the literature. 相似文献
999.
1000.
Progress in the catalytic asymmetric Claisen rearrangement of 2-alkoxycarbonyl-substituted allyl vinyl ether is reported. Application of a more Lewis acidic catalyst, [Cu{(S,S)-t-Bu-box}](H2O)2(SbF6)2, afforded β-chiral α-keto ester with an enantiomeric excess up to 99%. We suggest a highly polarized transition state for the Lewis acid-catalyzed Claisen rearrangement in order to explain the experimental results. 相似文献