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61.
In this study, a high power coupler designed for a tunable planar cavity is experimentally tested. The cavity consists of a periodical vane-type structure, of which the height of the vane can be mechanically adjusted so that the resonance frequency can be fine tuned. The cavity is designed to be operated at mode and resonant at 2.45 GHz. The high power coupler is composed of a rectangular waveguide and a cylindrical ceramic rod with tapered ends. One end of the ceramic rod is intruded into the gap between two vanes of the cavity. Through this coupler, the TE10 mode of the rectangular waveguide is converted into the TE11 mode of the ceramic rod and then couples to the TEM mode in the gap between vanes of the cavity. Experimental results show that a microwave power up to 5 kW can be effectively transmitted to excite the mode of the cavity . This cavity can be used to excite large area plasmas 相似文献
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64.
Quantitative enantiomeric analysis of chlorcyclizine,hydroxyzine, and meclizine by capillary electrophoresis 总被引:1,自引:0,他引:1
A simple capillary zone electrophoresis method was developed for the quantitative enantiomeric analysis of piperazine antihistamines with teratogenic suspicion in animals. Enantioseparation of chlorcyclizine, hydroxyzine, and meclizine was performed in glycine buffer (0.6 mol L-1; pH 3.00) with sulfated -cyclodextrin (5 mg mL-1) as a chiral selector; and the separated drugs were monitored by ultra-violet detector. The lower quantitation of the individual enantiomer is attainable at 10 µmol L-1, using an achiral piperazine drug (cyclizine) as internal standard. The method is simple and rapid with a short run time (<5 min) for the analysis of chlorcyclizine, hydroxyzine or meclizine enantiomers. 相似文献
65.
Teffo J Claveau C Kou Q Guelachvili G Ubelmann A Perevalov VI Tashkun SA 《Journal of Molecular Spectroscopy》2000,201(2):249-255
The 7000-8500 cm(-1) spectral region of (12)C(16)O(2) has been investigated using the high-resolution FT spectrometer of LPPM in Orsay. The two strongest bands in this region are the 10031 <-- 00001 and 10032 <-- 00001 bands centered at 8294 and 8192 cm(-1). Line intensities in these two bands and in the 40013 <-- 00001 and 40014 <-- 00001 bands have been measured. Using the method of effective operators, these line intensities have been included in a new fit of effective dipole-moment parameters to all available experimental data in the same spectral region of (12)C(16)O(2). The corresponding calculated line intensities of the 10031 <-- 00001 and 10032 <-- 00001 bands are compared with the experimental ones. Copyright 2000 Academic Press. 相似文献
66.
Wen-Hua Zhang Xiu-Bao Wei Ping-Ning Jin Jun-Feng Kou Guang Yang 《Transition Metal Chemistry》2011,36(5):459-463
Reactions of 3(5)-methyl-5(3)-phenyl-1H-1,2,4-triazole (3-Me-5-Ph-tzH) with AgNO3 in the absence/presence of NH3 yield a mononuclear [Ag(3-Me-5-Ph-tzH)2]NO3·3H2O (1) and a polymeric [Ag(3-Me-5-Ph-tz)]n (2), respectively. Two structurally different infinite chains, however, with the same formula of AgC9H8N3—one is double-decked and the other single zigzag—coexist in 1:1 ratio in the crystal of 2. As far as we know, 2 is the first binary silver(I) complex based on an asymmetric triazole and represents a rare case of two supramolecular isomers
coexisting in the same crystal. 相似文献
67.
68.
Cao‐Yuan Niu Xian‐Fu Zheng Ling‐Ling Bai Xiao‐Ling Wu Chun‐Hong Kou 《Acta Crystallographica. Section C, Structural Chemistry》2008,64(9):m305-m307
This study presents new coordinating modes of a Schiff base with three coordinating groups and an interesting two‐dimensional framework based on two types of constructing units. In the title compound, {[Ag(C14H10N4O)]ClO4}n, the AgI ion is coordinated by three N atoms and one O atom from three different N′‐(4‐cyanobenzylidene)isonicotinohydrazide (L) ligands, forming a primary distorted square‐planar coordination geometry. Two ligands each bridge two metal centres through one carbonitrile N atom in a monodentate mode and the hydrazide N and O atoms in a bidentate mode to form a small centrosymmetric (2+2)‐Ag2L2 ring as a principal constructing unit. The pyridyl N atoms from four ligands in four of these small rings coordinate to Ag atoms in adjacent rings to form a large hexanuclear silver grid. A two‐dimensional framework of rectangular grids is constructed from these small rings and large grids. Two perchlorate anions are located in each large grid and are bound to the grid by N—H...O hydrogen bonding. Crosslinking between the layers is achieved through long Ag...O interactions between the perchlorate anions and Ag atoms in adjacent layers. 相似文献
69.
Ai-Li Cui Guo-Xing Feng Ya-Fan Zhao Hui-Zhong Kou Hong Li Guang-Hua Zhu Ho-Soon Hwang Hee-Chang Oh Young-Jin Kwon Doo-Chul Lee 《Electrochemistry communications》2009,11(2):409-412
Electrochemical oxidation of graphite anode in deionized water at galvanostatic mode is investigated. It is found that mellitic acid and graphite oxide colloid (>20 nm) are coexisted as main products, as identified by XRD and TEM, FTIR and XPS. They can be separated successfully through several procedures. A few amounts of graphene and graphene rolls are also appeared as co-products. 相似文献
70.
对ISO/IEC17025-1999和ISO/IEC指南25-1990进行了比较,分析了ISO/IEC17025-1999的显著变化,提出了由ISO/IEC指南25-1990质量体系向ISO/IEC17025-1999质量体系过渡的措施。 相似文献