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991.
Guiying Chen Xin Liang Yizhe Yuan Guang Yang Chunping Zhang Tang Xu Q.W. Song 《Optik》2007,118(8):377-380
While two waves are coupled in bacteriorhodopsin (bR) film, a beam of incident light carrying the image is transferred to two diffraction beams whose intensities can increase from zero to a maximum and then decrease to a stable value with the increase of the writing time. Based on the relation among the polarization states of image in a recording beam and diffraction beams, we have proposed and demonstrated the all-optical image transfer switch which depends on the effective time and has the function that within the effective time, a polarization state image is automatically transferred to two images whose polarization states are perpendicular, and the transfer stops automatically beyond the effective time. A time-dependent all-optical image switch with muti-outputs is implemented. 相似文献
992.
993.
A 2‐fold parallel interpenetrated polymer, ZnCo(OH)(pheno)(p‐BDC)1.5·H2O ( 1 ) (pheno = phenanthrene‐9,10‐dione; p‐BDC = 1,4‐benzenedicarboxylate) has been prepared by hydrothermal synthesis and structurally characterized by IR, elemental analysis, ICP and single crystal X‐ray diffraction. Complex 1 crystallizes in the orthorhombic space group Pbca and affords a three‐dimensional (3D) six‐connected α‐Po network. The magnetic behavior for 1 was studied in the temperature range of 1.8‐300 K. 相似文献
994.
995.
996.
Dynamic characteristics have been studied for main components of machine tools by finite element method. The multi-element static and dynamic structural analysis program makes possible the analysis of main components in various computing models.The eigen pairs are solved by the transfer subspace iterative method with the advantages of high efficiency and precision. The program can be executed on the China-made computer TQ-16 and arbitrary sets of eigen pairs for the treatment of dynamic characteristics of complex structures of various kinds are thus obtained. 相似文献
997.
Peter Flury Cyril A. Grob Guang Yi Wang Hans-Werner Lennartz Wolfgang R. Roth 《Helvetica chimica acta》1988,71(5):1017-1024
Further evidence is presented that the 2-norbornyl cation is stabilized primarily by C(2)–C(6) bridging, and that C(2)–C(7) bridging leads to prohibitive strain. Thus, a comparison of the heats of hydrogenation of nortricyclene 17 and bicyclo[3. 2. 0. 0.2,7]heptane 18 indicates that the strain energy of the latter is ca. 21.5 kcal/mol higher that that of 17 . Furthermore, 6-exo-2-oxabicyclo[2. 2. 1]heptyl sulfonates 8 ionize with strong O(2) participation to the bridged oxonium ion 12. In contrast, 2-endo-7-oxabicyclo[2.2.1]heptyl sulfonates 11 ionize without O(7) participation to form the unbridged carbenium ion 15 . 相似文献
998.
本文描述农用薄膜中Al、Fe、Mg、Ca、Si、Cu、Ti杂质元素的发射光谱分析法,该方法直接压样于石墨电极中,简便,快速,取得了满意的结果。 相似文献
999.
1000.
A new approach to the back reaction of Hawking radiation on a Schwarzschild black hole (SBH), based on thermodynamics, is proposed, in which the thermodynamical system composed of SBH and thermal radiation in curved space is treated as a thermodynamical system composed of SBH, thermal radiation and a two-dimensional thermodynamical membrane (i.e. event horizon) in flat space. 相似文献