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Oxidation Protective C/SiC/Si-SiC Multilayer Coating for Carbon/Carbon Composites Applying at 1873 K

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Journal of Materials Science & Technology 2010年第12期26卷 1139-1142页

作者： Yulei zhang,Hejun li,Xinfa qiang and Kezhi li C/C Composites Research Center,State Key Laboratory of Solidification Processing,Northwestern Polytechnical University,Xi an 710072,China [a] C/C Composites Research Center State Key Laboratory of Solidification Processing Northwestern Polytechnical University Xi(an 710072 China

A C/SiC/Si-SiC multilayer coating for protecting carbon/carbon （C/C） composites against oxidation was prepared by slurry and pack cementation. X-ray diffraction （XRD） and energy dispersive spectroscopy （EDS） analysis showed that the inner coating obtained from the slurry and pack cementation was a C/SiC gradient layer acting as bonding layer, and the exterior coating formed in the second pack cementation was a Si-SiC double phase coating. Oxidation tests at 1873 K in air showed that the coating exhibited excellent oxidation protective ability and thermal shock resistance. The coating could effectively protect C/C composites from oxidation at 1873 K in air for 170 h and undergo the thermal cycling between 1873 K and room temperature for 8 cycles. The weight loss of the coated C/C composites is due to the formation of cracks and holes in the coating and the volatilization of SiO2 glass at high temperature.

关键词： Carbon/carbon composites Oxidation Coating

A 23 GHz high-temperature superconducting microstrip filter for radio astronomy

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Chinese Science Bulletin 2009年第19期54卷 3485-3488页

作者： GAO Lu GUO Jin WANG YueHui YU Tao zhang qiang li ChunGuang zhang Xueqiang li Hong li JunJie li WuXia GU ChangZhi MENG JiBao FENG Ji HE YuSheng Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China

This paper reports a 6-pole high-temperature superconducting (HTS) microstrip bandpass filter for radio astronomy applications. The filter has a center frequency of 23 GHz and a bandwidth the 2 GHz. We have made many efforts, such as adopting 0.25-mm-thick substrate, carefully designing the housing box and filter layout, to solve the problems in realizing a K-band planar filter. A special straight-line half-wavelength resonator (center-widen resonator) was also designed to reduce the insertion loss of the filter. The measured results showed a midband insertion loss of 0.11 dB with a ripple of 0.4 dB, and a return loss better than 11.5 dB. Good agreement was obtained between simulated and measured results.

关键词：微波传输带无线电通信电波天文学超导

A Study of Bioactivity of Corn Peptides with Low Molecular Weight Ⅱ: Effect on Plasma Free Amino Acid Concentrations in Rats

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Chemical Research in Chinese Universities 2003年第3期19卷 314-316页

作者： XU li zhang li-qiang WU Xiao-xia WANG Na zhang Xue-zhong Key Laboratory for Molecular Enzymology and Engineering of the Ministry of Education Jilin UniversityChangchun 130023P.R.China

The effects of the ingestion of corn peptides with a low molecular weight(LMCP) prepared from zein on some plasma free amino acid concentrations in rats that had taken ethanol were investigated. LMCP(1 0 g/kg body weight) in 15% ethanol(10 mL/kg body weight) was given to Wister rats by intragastrical administration. The amino acid analysis showed that the concentrations of alanine, leucine, and proline in the plasma reached their maximum levels at 30 min for the LMCP-intake group. They are 582.39, 99.60 and 272.51 μg/L , respectively. But in the control group, the plasma free amino acid levels were not changed obviously. Therefore, LMCP could cause an increase in concentration of some free amino acids such as alanine, leucine and proline etc . in plasma of the rats that have taken ethanol.

关键词： Corn peptide Bioactivity Plasma free amino acids

Effectiveness analysis of methane-drainage by deep-hole controlled pre-splitting blasting for preventing coal and gas outburst

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Journal of Coal Science & Engineering(China) 2009年第2期15卷 166-170页

作者： CAO Shu-gang li Yong liU Yan-bao zhang li-qiang XU A-meng Key Laboratory for Exploitation of Southwest Resources and Environmental Disaster Control Engineering Ministry of Education Chongqing University Chongqing 400044 China Safety Engineering College North China Institute of Science and Technology Beijing 101601 China

In the study of the application effectiveness of deep-hole controlled pre-splittingblasting technology,it was found through laboratory micro test and field study on a mine insouth China that under the technology,coal masses produce many irreversible ***,the nearer the distance from blasting hole,the larger the BET surface areaand volume ratio of the infiltration pore are;they increased by 11.47%and 5.73%,*** coefficient of air permeability is increased 4 *** 3 months,the gasdrainage rate was increased by 66%.In the first 15 days,the cumulative pumped gas was1.93 times of blasting *** average absolute gas emission decreased by 63.46%.Experimental results show that deep-hole controlled pre-splitting blasting not only preventscoal and gas outburst,but also gives good economic results.

关键词： coal and gas outburst methane-drainage pore structure deep-hole controlled pre-splitting blasting

Uniaxial stress influence on lattice,band gap and optical properties of n-type ZnO:first-principles calculations

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Chinese Physics B 2012年第1期21卷 399-403页

作者： Yang Ping li Pei zhang li-qiang Wang Xiao-liang Wang Huan Song Xi-Fu Xie Fang-Wei Laboratory of Advanced Manufacturing&Reliability for MEMS/NEMS/OEDS School of Mechanical EngineeringJiangsu UniversityZhenjiang 212013China

The lattice, the band gap and the optical properties of n-type ZnO under uniaxial stress are investigated by first- principles calculations. The results show that the lattice constants change linearly with stress. Band gaps are broadened linearly as the uniaxial compressive stress increases. The change of band gap for n-type ZnO comes mainly from the contribution of stress in the c-axis direction, and the reason for band gap of n-type ZnO changing with stress is also explained. The calculated results of optical properties reveal that the imaginary part of the dielectric function decreases with the increase of uniaxial compressive stress at low energy. However, when the energy is higher than 4.0 eV, the imaginary part of the dielectric function increases with the increase of stress and a blueshift appears. There are two peaks in the absorption spectrum in an energy range of 4.0-13.0 eV. The stress coefficient of the band gap of n-type ZnO is larger than that of pure ZnO, which supplies the theoretical reference value for the modulation of the band gap of doped ZnO.

关键词： uniaxial stress first-principles optical properties n-type ZnO

Formula Revision of Natural Ventilation Driven by Hot Pressure in Single Large Window Opening

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湖南大学学报（自然科学版） 2009年第S1期36卷 26-29页

作者： liN Wen,zhang Quan,HOU Xi-kuai,li Ping,ZHOU Jun-li,zhang Guo-qiang(Key Laboratory of Building Safety and Energy Efficiency(MOE),College of Civil Engineering,Hunan University,Changsha,Hunan 410082,China) Key Laboratory of Building Safety and Energy Efficiency College of Civil Engineering Hunan University Changsha 410082 China

This paper investigated the natural ventilation driven by hot pressure on a typical office building with single window *** actual result indicates that the ventilation rate of natural ventilation driven by hot pressure in the actual single window opening construction is very different from that obtained by the theoretical formula,since the ventilation conditions between actual environment and ventilation driven by hot pressure in the single window opening are ***,the theoretical formula is amended,and it becomes more consistent with the actual ventilation rate of natural ventilation driven by hot pressure under conditions that the construction is in the form of single window opening.

关键词： single opening natural ventilation theoretical formula

Primary cutaneous aspergillosis due to Aspergillus flavus: a case report

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中华医学杂志(英文版) 2005年第3期000卷 80-82页

作者： zhang qiang-qiang, li li, ZHU Min, zhang Chao-ying and WANG Jia-jun Department of Dermatology, Huashan Hospital, Fudan University, Shanghai 200040, China Department of Dermatology Huashan Hospital Fudan University Shanghai 200040 China

Infections caused by opportunistic organisms which have been known as etiologic agents of disease become more and more *** spp. is one of the agents. Fungi of aspergillus genus are widely distributed in nature, particularly in the soil and in the decomposed vegetation. They are frequent opportunist pathogens in immunocompromised patients. The most frequent causative organisms that cause cutaneous aspergillosis are *** and ***.1-3 In this report, we present a case of primary cutaneous aspergillosis manifested by ulceration of the shank due to A. flavus. The patient had no deficiency of immunological status and severe disease associated with fungal infection. Excellent response was shown to anti-fungal therapy.

关键词： Aspergillus flavus · cutaneous aspergillosis · terbinafine

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饶阳凹陷新近系馆陶组物源方向分析

吉林大学学报（地球科学版） 2012年第2期42卷 321-326,334页

作者：张立强中国石油大学地球科学与技术学院山东青岛266555

为了深入认识沉积物源的位置及古流向,通过矿物成分、岩屑特征、重矿物组合及分布、砂体展布特征等分析,对饶阳凹陷馆陶组的物源方向进行了系统研究。结果表明,饶阳凹陷新近系馆陶组沉积时期,盆地存在4个相对独立的物源及古水流体系:分... 详细信息

为了深入认识沉积物源的位置及古流向,通过矿物成分、岩屑特征、重矿物组合及分布、砂体展布特征等分析,对饶阳凹陷馆陶组的物源方向进行了系统研究。结果表明,饶阳凹陷新近系馆陶组沉积时期,盆地存在4个相对独立的物源及古水流体系:分别为来源于北或北东部物源自北向南或北东—南西流向的水系,来源于西部物源、西南—北东向展布的水系,源于西部物源、东西向展布的水系,源于南部或西南部物源、西南—北东向展布的水系。新近系的河流流向以南北向、沿盆地长轴方向为主,盆地内砂体具有南北向带状展布的特征;中部留路地区距离物源区相对较远、盖层较发育、储盖组合条件好,为饶阳凹陷新近系油气聚集的有利区带。

关键词：饶阳凹陷新近系物源沉积环境沉积

Gelation behavior of Antheraea pernyi silk fibroin

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Science China Chemistry 2010年第3期53卷 535-541页

作者： YAN ShuQin,ZHAO ChunXia,WU XiuFang,zhang qiang & li MingZhong National Engineering Laboratory for Modern Silk College of Textile and Clothing Engineering,Soochow University,Suzhou 215123,China 1. National Engineering Laboratory for Modern Silk College of Textile and Clothing Engineering Soochow University Suzhou 215123 China

The sol-gel transition behavior of Antherae pernyi silk fibroin(Ap-SF) has not been systematically *** this work,the influence of environmental temperature,pH,the concentration of Ap-SF,K+ and Ca2+ on the gelation time,and the structural changes of Ap-SF in sol-gel transformation were *** results indicated that the gelation time of the Ap-SF aqueous solution decreased with the increase of the Ap-SF concentration and environmental *** sol-gel transformation of Ap-SF was much more rapid than that of Bombyx mori silk fibroin under the same *** Ap-SF was sensitive to changes in the concentration of Ca2+ and K+.Upon gelation,the random coil structure of the Ap-SF was significantly transformed into the β-sheet structure.

关键词： Antheraea pernyi silk fibroin gelation sol-gel transition