OALib Journal期刊

ISSN: 2333-9721




2019 ( 27 )

2018 ( 282 )

2017 ( 320 )

2016 ( 310 )


匹配条件: “MA Jian-guo” ,找到相关结果约80288条。
The Propagation and Cutoff Frequencies of the Rectangular Metallic Waveguide Partially Filled with Metamaterial Multilayer Slabs
Dan Zhang;Jian-Guo Ma
PIER M , 2009, DOI: 10.2528/PIERM09082701
Abstract: In this paper, the wave propagation and the cutoff frequencies of a rectangular metallic waveguide, partially filled the metamaterial multilayer slabs have been studied. The equations of the TMM method are not complex and the numerical examples show that we can easily obtain the characteristics of the metamaterial multilayer's rectangular waveguide satisfyingly. The cutoff frequencies of the metamaterial waveguide show very different characteristics compared with the usual waveguide.
Compilation and practice for "Genetics" multimedia textbook

SHI Chun-Hai,WU Jian-Guo,MA Qiu-Lan,

遗传 , 2009,
Abstract: 教材是传授知识的重要载体,与教学质量有着密切关系.文章根据多媒体教学已在我国高等教育教学中普遍采用的实际情况,对<遗传学>多媒体教材的编写形式、遗传学内容和知识点的选择、教材知识模块和结构体系的安排以及多媒体教材编写的特点等方面进行了探讨和实践.
Induction motor tracking control based on passivity principle--In case of time-varying and unknown load torque and rotor resistance

MA Liang-he,JIANG Jian-guo,

控制理论与应用 , 2005,
Abstract: 研究了负载转矩和转子电阻在一般的未知时变情形时对异步电动机期望时变电磁转矩的渐近跟踪控制问题.首先给出了转子电阻和负载转矩在时变已知的情形时无源性控制器的设计方法,然后通过设计负载转矩和转子电阻的在线估计器,得到了转子电阻和负载转矩在时变但未知的一般情形下无源性控制器的设计.仿真结果证明了这样设计的控制器具有良好的性能.
Characterization and Electrorheological Effect of H2SO4-modified TiO2 Particles
GAO Lan,MA Hui-Ru,LIU Yang-Sheng,GUAN Jian-Guo
无机材料学报 , 2009, DOI: 10.3724/sp.j.1077.2009.01121
Abstract: H2SO4-modified TiO2 particles were prepared using a sol-gel method followed by impregnating the dry gels with sulphuric acid and were used to fabricate an electrorheological (ER) fluid with high ER activity. The as-synthesized H2SO4-modified TiO2 particles were characterized by fourier transform infrared (FT-IR), X-ray diffraction (XRD), BET N2 adsorption-desorption isotherm analysis, and the ER effect and dielectric spectra of the ER fluids were measured. The results show that H2SO4-modified TiO2 particles have smaller size of crystal grains and higher specific surface area due to the restraint of SO42- from the grain growth. Under the same measured condition and electric field strength of 3kV/mm, the ratio of fielda2induced shear stress to zero field shear stress (| /EM>E/| /EM>0) of TiO2 particles is 80, while that of H2SO4-modified TiO2 particles is more than 500. The observed ER performances are reasonably explained by the stronger interfacial polarization, which is brought by the specific structures of the H2SO4-modified TiO2 particles.
[1,1′-Bis(dicyclohexylphosphino)cobaltocenium-κ2P,P′]chlorido(η5-cyclopentadienyl)ruthenium(II) hexafluoridophosphate
Jian-Guo Hou
Acta Crystallographica Section E , 2010, DOI: 10.1107/s1600536810001790
Abstract: In the title structure, [CoRu(C5H5)(C17H26P)2Cl]PF6, the RuII atom is bonded to a cyclopentadienyl ring, a Cl atom and two P atoms of the chelating 1,1′-bis(dicyclohexylphosphino)cobaltocenium (di-cypc) ligand, leading to a three-legged piano-stool coordination. Part of the PF6 counter-anion is disordered over two positions, with a site-occupancy ratio of 0.898 (7):0.102 (7). The components are linked by C—H...F and C—H...Cl hydrogen bonds.
Jian-Guo Chang
Acta Crystallographica Section E , 2009, DOI: 10.1107/s1600536809041427
Abstract: The title compound, C26H18Cl2N2O2, was synthesized by the reaction of (5-chloro-2-hydroxyphenyl)(phenyl)methanone with hydrazine hydrate. The molecule possesses a crystallographically imposed centre of symmetry at the mid-point of the N—N bond. The conformation of the molecule is stabilized by an intramolecular O—H...N hydrogen bond.
Jian-Guo Wang
Acta Crystallographica Section E , 2011, DOI: 10.1107/s1600536811017272
Abstract: In the title compound, C10H12O2, the substituted benzene ring is inclined at a dihedral angle of 75.9 (1)° to the almost planar butan-2-one substituent (r.m.s. deviation = 0.02 ). In the crystal, intermolecular O—H...O hydrogen bonds link the molecules into chains along the a axis.
Jian-Guo Chang
Acta Crystallographica Section E , 2011, DOI: 10.1107/s1600536811048495
Abstract: The title compound, C15H12BrClN2O2, was synthesized by the condensation of 1-(5-bromo-2-hydroxyphenyl)ethanone with 2-chlorobenzohydrazide in anhydrous ethanol. The Schiff base molecule displays a trans configuration with respect to the C=N double bond. The dihedral angle between the two benzene rings is 13.74 (3)°. The molecular conformation is stabilized by an intramolecular O—H...N and the crystal structure by intermolecular N—H...O hydrogen bonds.
[1,1′-Bis(diphenylphosphanyl)cobaltocenium]carbonylchloridohydrido(triphenylphosphane)ruthenium(II) hexafluoridophosphate dichloromethane disolvate
Jian-Guo Hou
Acta Crystallographica Section E , 2011, DOI: 10.1107/s1600536811044035
Abstract: In the title compound, [CoRu(C17H14P)2ClH(C18H15P)(CO)]PF6·2CH2Cl2, the RuII atom is coordinated by three P atoms from a chelating 1,1′-bis(diphenylphosphanyl)cobaltocenium ligand and a triphenylphosphine ligand, one CO ligand, one Cl atom and one H atom in a distorted octahedral geometry. In the cobaltocenium unit, the two cyclopentadienyl rings are almost parallel, making a dihedral angle of 1.2 (3)°. The F atoms of the hexafluoridophosphate anion are disordered over two sets of sites, with an occupancy ratio of 0.849 (11):0.151 (11). Intramolecular C—H...Cl hydrogen bonds occur in the complex cation. The complex cations, hexafluoridophosphate anions and dichloromethane solvent molecules are linked by intermolecular C—H...F hydrogen bonds.
Jian-Guo Chang
Acta Crystallographica Section E , 2011, DOI: 10.1107/s1600536811050720
Abstract: The crystal structure of the title complex, [Cu2(C15H10Cl2N2O2)2(C5H5N)2], features centrosymmetric dimers. The CuII ion is pentacoordinated in a quadratic pyramidal mode. The quadratic plane is formed by the O,O′,N-tridentate ligand and a pyridine molecule. The fifth coordination site is occupied by the O atom of another ligand showing a significantly longer Cu—O bond.

Copyright © 2008-2017 Open Access Library. All rights reserved.