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Theoretical Study on the Structural and Electronic Properties of the Reduced SnO_2 (110) Surface

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Chinese Journal of Structural Chemistry 2007年第5期26卷 606-612页

作者： ZHANG Yong-Fan liN wei WANG Qi-wei li Yi li jun-Qian Department of Chemistry Fuzhou University Fuzhou Fujian 350002 China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter The Chinese Academy of Sciences Fuzhou Fujian 350002 China

The reduced SnO2（110） surface has been investigated by using first-principles method with a slab model. By examining the vacancy formation energy of three kinds of reduced SnO2（110） surfaces, the most energetically favorable defect surface is confirmed to be the surface with the coexistence of bridging and in-plane oxygen vacancies, which is different with the traditional model by only removing bridging oxygen. The results of band structure calculations indicate that the electronic structure of this defect surface is similar to the SnO surface.

关键词： SnO2(110) surface band structure defect state

Pumping speed of cryopump for xenon

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航空动力学报 2015年第7期30卷 1731-1736页

作者： liNG Gui-long wei li-jun CAI Guo-biao School of Astronautics Beijing University of Aeronautics and Astronautics Unit 93469 the Chinese People's Liberation Army

The xenon pumping speed testing system of the large-diameter external cryopump was designed to meet the plume test requirements for prototype electric *** flowmeter method was utilized to measure the xenon pumping *** test results show that the averaged effective pumping speed of doublecryopumps is 52 200L/s,and that of single-cryopump is 27 100L/*** pumping speed ratio of two configurations is *** can be concluded that the pumping speed has in linear relationship with the number of cryopump,and the coefficient is irrelevant with the gas *** averaged effective pumping speed of xenon is less than its nominal pumping speed,and the averaged pumping efficiency is *** the identical inflow conditions,the averaged effective pumping speed ratio of nitrogen is 0.53,slightly less than the theoretical pumping speed ratio of ***,it can be concluded that results assessment of large-diameter external cryopump design index can guide the engineering application,showing certain reference significance.

关键词： vacuum plume large-diameter external cryopump xenon pumping speed test

Radar target recognition based on micro-Doppler effect

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Optoelectronics Letters 2008年第6期4卷 456-459页

作者： DONG wei-guang li Yan-jun College of Astronautics Northwestern Polytechnical University Xi ＇an 710072 China

Mechanical vibration of target structures will modulate the phase function of radar backscattering,and will induce the frequency modulation of returned signals from the target. It generates a side bands of the target body Doppler frequency shift,which is helpful for target recognition. Based on this,a micro-Doppler atomic storehouse is built for the target recognition,and four kinds of common classifiers are used separately to perform the classified recognition. The simulation experimental results show that this method has high recognition rate above 90%.

关键词：雷达目标显微多普勒效应信息处理后向散射

2D-QSAR Studies on Triazolone Compounds Containing Benzenesulfonic Amide

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Chinese Journal of Structural Chemistry 2007年第8期26卷 883-888页

作者： wei Qing-li GAO jun SUN Dao-Xing ZHANG Shu-Sheng College of Chemistry and Molecular Engineering Qingdao University of Science ＆ Technology Qingdao 266042 China

The geometry structures of 6 triazolone compounds containing benzenesulfonic amide were fully optimized with DFT （Density Functional Theory） method at the B3LYP/6-31G level, and the structural and electronic parameters of the compounds were calculated. The hydrophobic and topological parameters of the title compounds were calculated by HyperChem software. The mono- and bi-parametric models between the parameters and biological activity of the compounds were analyzed by Multiple linear Regression method based on Hansch-Fujita model. The results show that the activities of the title compounds were increased with higher hydrophobic property logP and molecular volume V, lower molecular energy ETOTAL and electronegative of benzene ring Qph.

关键词： benzenesulfonic amide triazolone compounds 2D-QSAR DFT method

Mechanism of brittle-ductile transition of a glass-ceramic rigid substrate

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International Journal of Minerals,Metallurgy and Materials 2011年第2期18卷 229-233页

作者： Yu-li Sun Dun-wen Zuo Hong-yu Wang Yong-wei Zhu jun li Jiangsu Key Laboratory of Precision and Micro-manufacturing Technology College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

The hardness, elastic modulus, and scratch resistance of a glass-ceramic rigid substrate were measured by nanoindentation and nanoscratch, and the fracture toughness was measured by indentation using a Vickers indenter. The results show that the hardness and elastic modulus at a peak indentation depth of 200 nm are 9.04 and 94.70 GPa, respectively. These values reflect the properties of the glass-ceramic rigid substrate. The fracture toughness value of the glass-ceramic rigid substrate is 2.63 MPa？m1/2. The material removal mechanisms are seen to be directly related to normal force on the tip. The critical load and scratch depth estimated from the scratch depth profile after scratching and the friction profile are 268.60 mN and 335.10 nm, respectively. If the load and scratch depth are under the critical values, the glass-ceramic rigid substrate will undergo plastic flow rather than fracture. The formula of critical depth of cut described by Bifnao et al. is modified based on the difference of critical scratch depth

关键词： brittle-ductile transition critical conditions glass ceramics nanoindentation nanoscratch

Design of violet InGaN light-emitting diode with staggered quantum well structure

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Optoelectronics Letters 2008年第6期4卷 399-402页

作者： li wei-jun ZHANG Bo XU Wen-Lan LU wei State key Laboratory for Infrared Physics Shanghai Institute of Technical Physics Chinese Academy of Sciences Shanghai 200083 China Department of Electronic Engineering East China Normal University Shanghai 200062 China

The staggered InGaN quantum well (QW) structure and the conventional InGaN QW structure for the emission at a particu-lar wavelength of 400 nm are designed and theoretically investigated,including the distribution of the carriers’ concentration,the radiative recombination rate,the Shockley-Read-Hall (SRH) recombination rate as well as the output performance and the internal quantum efficiency. The theoretical result indicates that the staggered QW structure offers significant improve-ment of carriers’ concentration in the QW,especially the hole concentration. The output power and the internal quantum efficiency also show 32.6 % and 32.5 % enhancement,respectively,in comparison with that of the conventional InGaN QW structure. The reduction of the electron overflow can be the main factor for the improvement of the optical perfor-mance for novel staggered InGaN QW structure.

关键词：发光二级管量子阱波长 SRH

Expression of non-structural protein NS3 gene of Bombyx mori densovirus (China isolate)

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Journal of Genetics and Genomics 2008年第4期35卷 239-244页

作者： Huijuan Yin Qin Yao Zhongjian Guo Fang Bao wei Yu jun li Keping Chen Institute of life Sciences Jiangsu University 301# Xuefu Road Zhenjiang 212013 China

The invertebrate parvovirus Bombyx mori Densonucleosis Virus type 3 （China isolate）, named BmDNV-3, is a kind of bidensovirus. It is a new type of virus with unique replication mechanisms. To investigate the effects of the NS3 gene during viral DNA replication, a pair of primers was designed for amplifying NS3 gene of Bombyx mori densovirus （China isolate）. Gene NS3 amplified was cloned into a prokaryotic expression vector pET-30a and the donor plasmid pFastBacHTe, respectively. The NS3 protein was expressed in Escherichia coli BL21. The pFastBacHTe-NS3 was transformed to E. coli DHIOBac. The recombinant bacmid baculoviruses （rBacmid-EGFP-NS3） isolated from the white colonies were transfected into BmN-4 cells using a transfection reagent. BraN-4 cells were infected with recombinant virus to express fusion proteins. The expression of fusion protein around 30 kDa in E. coli BL21 was identified by SDS-PAGE, Western blotting, and mass spectrometry. The expressed NS3 protein by B. mori nucleopolyhedrovirus bacmid system was confirmed by Western blotting using an anti-NS3 polyclonal antibody. And about 45 kDa protein was found. The expressed fusion protein was smaller than the expected size of EGFP-NS3, 55 kDa. Western blotting analysis indicated that EGFP-NS3 protein was expressed in infected larvae with smaller molecular size.

关键词： BmDNV NS3 protein expression

Fermentation Performance and Characterization of Cold-Adapted lipase Produced with Pseudomonas lip35

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Agricultural Sciences in China 2009年第8期8卷 956-962页

作者： YU Hong-wei HAN jun li Ning QIE Xiao-sha JIAYing-min Institute of Food Science and Technology Agricultural University of Hebei Baoding 071001 PR.China

Strain of Pseudomonas lip35 producing lipase was isolated in a refrigerator. lipase production and characterization of this strain were investigated under different conditions. The Pseudomonas was cultivated in shaking flasks in a fermentation medium in various nutritional and physical environments. lipase production has been influenced by the presence of yeast-extract, soybean powder, NaCI, and Tween-80. Maximum lipase productivity was obtained when the physical environment of the fermentation medium was optimal for 67 h. The production of lipase reached 58.9 U·mL^-1. The lipase of Pseudomonas lip35 can be considered to be inducible, but the inducer had little influence on the production of lipase. The lipase was characterized and showed high lipolytic activity from pH 7.5-8.0. The optimum temperature was observed at 20℃ and the thermal inactivation of lipase was obvious at 60℃. The lipase activity was inhibited by K＋, stimulated by Ca^2＋, and thermostability decreased in the presence of Ca^2＋, therefore the lipase was Ca^2＋ -dependent cold-adapted enzyme.

关键词： cold-adapted lipase fermentation optimization lipase characterization Pseudomonas lip35

Gravitational Deflection of Massive Particles by a Schwarzschild Black Hole in Radiation Gauge

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Communications in Theoretical Physics 2019年第10期71卷 1219-1226页

作者： Zong-Hai li Xia Zhou wei-jun li Guan-Sheng He School of Physical Science and Technology Southwest Jiaotong UniversityChengdu610031China Physics and Space Science College China West Normal UniversityNanchong637009China School of Mathematics and Physics University of South ChinaHengyang421001China

The exact metric of a Schwarzschild black hole in the true radiation gauge was recently reported. In this work, we base on this gravity and calculate the gravitational deflection of relativistic massive particles up to the fourth post-Minkowskian order. It is found that the result is consistent with the previous formulations for both the case of dropping the fourth-order contribution and the case of light deflection. Our result might be helpful for future high-accuracy observations.

关键词： gravitational deflection relativistic massive particles radiation gauge Schwarzschild black hole