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91.
Hong-Ji Chen Wen-Juan Yu Xiao-Ming Chen Wen-Jie Zheng 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(11):1285-1287
The title polymeric complex, [Cd(SCN)2(C12H12N2O)], exhibits a three-dimensional framework in which each CdII atom is bridged by two η-1,3-(SCN)− groups, forming a double-stranded chain. The unique CdII atom lies on an inversion centre and the coordination sphere is completed by two terminal N atoms from two different 4,4′-oxydianiline (4,4′-Oda) ligands, furnishing a CdS2N4 octahedral geometry. Adjacent polymeric double-stranded chains are linked via the 4,4′-Oda ligands, which lie across twofold rotation axes. 相似文献
92.
We calculate the unpolarized cross sections for dissociation reactions of charmonia in collisions with π,ρ and K in a potential that is derived from QCD.The reactions are governed by the quark-interchange processes.The mesonic quark-antiquark relative-motion wave functions are determined by the central spinindependent terms of the potential.The numerical wave functions and cross sections are parametrized.The difference of transition amplitudes in the prior form and in the post form is explored by deriving and examining the transition amplitudes of the one-gluon-exchange spin-spin term of the potential in the two forms.We find that the post-prior discrepancy in meson-meson elastic scattering that is governed by quark-interchange processes depends on the difierence of quark or antiquark masses and of quark-antiquark spatial distributions ofthe two mesons. 相似文献
93.
In the solid state, interlocking of the lateral phen ligands at the acute angle sites of the molecular [Cu2(bpa)2-(phen)2(H2O)]2 rhombi via aromatic pi-pi stacking interactions into the cavities of the adjacent rhombi generates laminated polyrotaxanes that are further assembled into a 3D network via similar interactions between the phen ligands at the obtuse angle sites. 相似文献
94.
本文对采用二氧化碳作为基本工作流体的半闭环燃气轮机循环的空气动力学特性进行了详尽的分析.结果表明,不同工作流体的比热比值对压气机的压比、等熵效率及临界堵塞质量流量影响很大,并详细阐述了一种比热比对透平机械性能影响的修正方法,进而提出了一种零排放发动机的设计新思路,揭示了最初为空气工质而设计的压气机可以直接用于CO2零排放发动机中. 相似文献
95.
对于硅薄膜太阳电池来说, 无论是PIN型还是NIP型太阳电池, 采用绒面陷光结构来提高入射光的有效利用率是提高太阳电池效率的重要方法之一.本文采用标度相干理论对PIN和NIP型电池的绒面结构的陷光性能进行了数值模拟. 结果表明: PIN电池中前电极和NIP电池中背电极衬底粗糙度分别为160和40 nm时可获得理想的陷光效果; 在不同粗糙度背电极衬底上制备a-SiGe:H电池发现, 使用40和61.5 nm 背电极可获得相当的短路电流密度, 理论分析和实验得到了一致的结果.
关键词:
陷光结构
光散射能力
标量相干理论
硅基薄膜太阳电池 相似文献
96.
The isostructural, chiral molecular magnetic materials with the formula [MxM'(2-x)(ca)2(1,4-dimb)]n [H2ca = D-(+)-camphoric acid, 1,4-dimb = 1,4-di-(1-imidazolyl-methyl)-benzene, M = Ni(II), M' = CoII, 0 < or = x < or = 2] consist of ca-bridged (4,4) layers with [M2(O2CR)4] as secondary building units that are pillared by the 1,4-dimb ligands into a unique 3D framework. The high-spin octahedral symmetry and the proportions of the mixed-metal ions were characterized by UV-vis spectroscopy. The compounds exhibit the onset of antiferromagnetic ordering at 7.5 approximately 23 K, as well as weak ferromagnetism, spin-flop, and glassy behavior that result from the randomness of the mixed-metal pairs, magnetic anisotropy of the metallic cations, and antisymmetric exchange. The composites should be regarded as molecular alloys of the pure Ni(II) and Co(II) compounds. The magnetic behavior of the solid solutions shows unambiguously that the organic bridges, bond angles, and bond distances greatly influence the effective interactions and bring about cooperative magnetic behavior in the chiral 3D frameworks. 相似文献
97.
冻干法处理过的药品瓶中残存的水汽(H2O)是药品变质的主要影响因素之一, 如何快速准确地测量瓶中的水汽浓度及压力, 是检测药瓶是否泄漏的关键. 本文报道了利用1.39 μm半导体激光器作为光源, 结合波长调制吸收光谱技术, 实现了对密闭玻璃容器(药瓶)中水汽浓度及压力的探测, 并通过转台模拟生产线对系统在动态条件下的性能进行了测试. 研究结果表明, 在0.2%-12%的H2O浓度范围内真实值与测量值之间的相关度和标准偏差为0.9978 和4.81%, 在0.1-100 atm (1 atm=1.01325×105 Pa)的压力范围内两者之间的相关度和标准偏差为0.982和5.6%, 系统对应的压力及浓度的最低检测限约为2.5 Torr (1 Torr=1.33×102 Pa)和400 ppm. 通过利用转台以及Labview编写的快速在线处理软件进行了动态条件下的测试, 一分钟可以处理300个左右的药瓶, 可以很好地满足快速实时探测的要求. 该方案可以直接应用于药瓶在线检测, 并且使用2台激光器可以实现多组分同时探测分析(如H2O、氧气等). 相似文献
98.
Cellulose 3,5-dimethylphenylcarbamates bearing a low content of a vinyl group at the 6-position on the glucose units were synthesized by a previously developed regioselective method and chemically immobilized onto a vinylized silica gel as chiral stationary phases (CSPs) for high-performance liquid chromatography (HPLC). The immobilization of the derivatives was performed through a radical polymerization reaction with AIBN as the initiator in the presence of toluene. The effects of vinyl monomers, such as isoprene, 2,3-dimethyl-1,3-butadiene (DMBD), ethylene glycol dimethacrylate (EDMA) and 1,5-hexadiene, on the immobilization and enantioselectivities of the derivatives were investigated. The effect of the temperature used for the radical polymerization reaction on the immobilization was also examined. In addition, the direct comparison of the chiral recognition abilities of the laboratory-made and commercially available columns was discussed. 相似文献
99.
在远离光子晶体光纤零色散波长的正常色散区入射飞秒脉冲,实验产生了一对由四波混频引起的信号波带和闲频波带,及一对由脉冲内拉曼散射和非孤子辐射引起的孤子和色散波带,并观察到功率饱和现象.利用有限元法理论模拟了光纤的色散和非线性特性,用四波混频的相位匹配条件模拟了光纤在满足相位匹配条件下所产生的信号波带和闲频波带出现的可能位置,并与实验结果符合得很好.结果表明:即使在光子晶体光纤的正常色散区抽运激光脉冲亦可以产生四波混频和孤子效应;研究发现四波混频的产生是由四阶色散参量引起的;并进一步从理论上解释了孤子及色散波的产生原因. 相似文献
100.
Numerical Study on Left-Handed Materials Made of Ferrite and Metallic Wires 总被引:1,自引:0,他引:1 下载免费PDF全文
Due to coupling effect, we show that it is difficult to realize the left-handed material by placing metallic wires directly into a ferrite matrix. However by introducing an insulating material round the metallic wires to decouple the direct interaction between the metallic wire and ferrite matrix, we have proposed two microstructures, which are shown by numerical simulation to have negative refractive indexes. The influence of microstructure on the transmission property is also examined. 相似文献