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化工学报 2005年第6期56卷 1150-1155页

作者：刘艳升中国石油大学(北京) 北京102249

论述了板式塔负荷性能图方法在实践应用中的若干问题.包括按照水力学操作极限和传质操作限制的概念构造负荷性能图、适宜坐标选择的讨论、塔板超限制操作判断问题,提出了可行稳定域分析概念,用于分析精馏塔全面进料条件变化的情况等.

关键词：负荷性能图板式塔可行稳定域

LM-3 Launch Vehicle Series

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Aerospace China 1994年第2期 15-17页

作者： He Zuming and liu yansheng

The LM-3 launch vehicle series include LM-3, LM-3A and LM-3B. LM-3 The LM-3 is a large launch vehicle with multiple purposes. Its liftoff mass is about 202t, and liftoff thrust is 2744kN. The LM-3 stands 43.25m tall, with the diameters of the first and second stages being 3.35m and the third 2.25m. The LM-3 is launched from the Xichang Satellite Launch Center. Its flight may be divided into the first stage’s operation phase, the second stage’s opera-

关键词： launch diameters opera thrust stands instrument orbit payload attitude helium

COLD ROLLING AND RECRYSTALLIZATION TEXTURE OF CROSS SHEAR ROLLED COMMERCIAL COPPER

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Acta Metallurgica Sinica(English Letters) 1990年第12期3卷 410-414页

作者： liu yansheng ZHAO Xiang LIANG Zhide Northeast University of Technology,Shenyang,China

The texture change along the normal direction to rolling plane of cross shear rolled commer- cial copper has been studied by means of two step method for ODF caleulation and computer *** texture of cross shear rolling of copper is similar in primary components to that of conventional cold rolling,but the scattering degree and direction of the texture are dif- ferent,due to the residual shear strain change in different position along the normal to rolling *** seems that no more effect of the shear strain upon the recrystallization texture.

关键词： cross shear rolling cold rolled texture recrystallization texture texture simulation

Photoluminescence Properties of Porous Silicon Based on FZ(H) Si Wafer

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Rare Metals 2001年第1期20卷 38-42,57页

作者： Yuejiao He, Huaixiang Li, Chenghua Guo, Guirong liu, yansheng Chen, Shuzhen Duan (Institute of Semiconductors, Shandong Normal University, Jinan 250014, China Metallurgy School, University of Science and Technology Beijing, Beijing 100083, China) Shandong Normal Univ Inst Semicond Jinan 250014 Peoples R China Univ Sci & Technol Beijing Met Sch Beijing 100083 Peoples R China

The photoluminescence (PL) properties of porous silicon (PS) have been studied based on n-type single-crystal (111) silicon wafers (80-90 Omega .cm in the resistivity). The porous silicon layers (PSL) were created by anodizing the wafers with a denuded zone of 20-40 mum formed by neutron transmutation doping (NTD) and thermal treatment at 940 degreesC for 4 h and then 700 degreesC for 2 h, two-step heating of the floating-zone silicon (FZ Si) grown in a hydrogen (H,) ambience. By surface modification with stannic chloride or amine immersion and rapid thermal oxidation (RTO), the PL peak position from the PS can be qualitatively controlled factitiously. The as-prepared PS shows an orange-yellow luminescence, while the modified samples emit red, green and blue luminescence. Mechanisms for the different colors of the PL are discussed. Fourier transform infrared (FTIR) is carried out to analyze the differences in the structural configuration of the PS samples.

关键词： porous silicon photoluminescence surface modification rapid thermal oxidation

Surgical intervention combined with weight-bearing walking training improves neurological recoveries in 320 patients with clinically complete spinal cord injury:a prospective self-controlled study

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Neural Regeneration Research 2021年第5期16卷 820-829页

作者： yansheng liu Jia-Xin Xie Fang Niu Zhexi Xu Pengju Tan Caihong Shen Hongkun Gao Song liu Zhengwen Ma Kwok-Fai So Wutian Wu Chen Chen Sujuan Gao Xiao-Ming Xu Hui Zhu Kunming International Spine and Spinal Cord Injury Treatment Center Kunming Tongren HospitalKunmingYunnan ProvinceChina Clinical Center for Spinal Cord Injury Kunming General Hospital of Chengdu Military CommandKunmingYunnan ProvinceChina Department of Laboratory Animal Sciences Shanghai Jiao Tong University School of MedicineShanghaiChina Department of Ophthalmology and State Key Laboratory of Brain and Cognitive Sciences The University of Hong KongHong Kong Special Administration RegionChina Guangdong-Hongkong-Macao Institute for Central Nervous System Regeneration Jinan UniversityGuangzhouGuangdong ProvinceChina Re-Stem Biotechnology Co.Ltd.SuzhouJiangsu ProvinceChina Spinal Cord and Brain Injury Research Group Stark Neurosciences Research InstituteDepartment of Neurological SurgeryIndiana University School of MedicineIndianapolisINUSA Department of Biostatistics Indiana University School of MedicineIndianapolisINUSA

Although a large number of trials in the SCI field have been conducted,few proven gains have been realized for *** the present study,we determined the efficacy of a novel combination treatment involving surgical intervention and long-term weight-bearing walking training in spinal cord injury(SCI)subjects clinically diagnosed as complete or American Spinal Injury Association Impairment Scale(AIS)Class A(AIS-A).A total of 320 clinically complete SCI subjects(271 male and 49 female),aged 16–60 years,received early(≤7 days,n=201)or delayed(8–30 days,n=119)surgical interventions to reduce intraspinal or intramedullary *** days post-surgery,all subjects received a weight-bearing walking training with the“Kunming Locomotion Training Program(KLTP)”for a duration of 6 *** neurological deficit and recovery were assessed using the AIS scale and a 10-point Kunming Locomotor Scale(KLS).We found that surgical intervention significantly improved AIS scores measured at 15 days post-surgery as compared to the pre-surgery baseline *** improvement of AIS scores was detected at 3 and 6 months and the KLS further showed significant improvements between all pair-wise comparisons of time points of 15 days,3 or 6 months indicating continued improvement in walking scores during the 6-month *** conclusion,combining surgical intervention within 1 month post-injury and weight-bearing locomotor training promoted continued and statistically significant neurological recoveries in subjects with clinically complete SCI,which generally shows little clinical recovery within the first year after injury and most are permanently *** study was approved by the Science and Research Committee of Kunming General Hospital of PLA and Kunming Tongren Hospital,China and registered at ***(Identifier:NCT04034108)on July 26,2019.

关键词： American Spinal Injury Association Impairment Scale–A functional recovery human intramedullary decompression spinal cord injury surgical intervention walking training

Corrosion Behavior of Anodic Oxidized TiO_2 Film in Seawater

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Journal of Ocean University of China 2010年第4期9卷 376-380页

作者： WANG Min WANG Wei HE Benlin SUN Mingliang YIN yansheng liu Lan ZOU Wuyuan XU Xuefei Institute of Materials Science and Engineering Ocean University of China Qingdao 266100 P. R. China

TiO2 films were formed on metallic titanium substrates by the anodic oxidation method in H2SO4 solution under the 80V D.C..Phase component and microstructure were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM).Water contact angles on titanium oxide film surface were measured under both dark and sunlight illumination *** tests were carried out in seawater under different illumination conditions by electrochemistry impedance spectrum (EIS) and polarization *** result showed that the TiO2 film prepared by the anodic oxidation method was anatase with a uniform structure and without obvious pores or cracks on its *** average water contact angle of the film was 116.4? in dark, in contrast to an angle of 42.7? under the UV illumination for 2 hours, which demonstrates good hydrophobic *** anti-corrosion behavior of the TiO2 film was declining with the extended immersion *** dark conditions, however, the hydrophobic TiO2 film retarded the water infiltrating into the *** impedance changed slowly and the corrosion current density was 2 orders of magnitude lower than that with the film illuminated by *** of those mentioned above indicate that the TiO2 film possesses much better performance under dark condition, and it can be applied as an engineering material under dark seawater environment.

关键词： TiO2 film anodic oxidation method hydrophobic corrosion resistance electrochemistry impedance spectrum(EIS)

垂直锐边孔口的自由出流特性(Ⅲ)孔几何形状对孔流系数的影响

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化工学报 2009年第5期60卷 1121-1126页

作者：曹睿刘艳升中国石油大学(北京)化学科学与工程学院北京102249

The behavior of the fluid flowing through vertical sharp-edged orifices with the same cross-section area but different geometry was investigated experimentally on typical "large orifice" and "small orifice".The profiles of orifice discharge coefficient curves of circular,elliptical,square,rectangular and triangular orifices were similar,and the profile of the circular one is the highest and that of the triangular one is the *** can be concluded that the orifice’s geometry has some effect on orifice discharge,but it is not the key parameter,because it doesn’t change the orifice’s flow mechanism *** effects of the orifice’s geometry on energy losses were evaluated based on the analysis of the hydraulic radius of orifice,interfacial tension in acute angle,and penetrating phenomenon of jet flow through non-circular orifices,which might complement the flow mechanism of the circular orifice the authors studied ***,the orifice flow was simulated with CFD software Fluent 6.2 in order to investigate the effect of orifice’s geometry on velocity distribution and energy losses of orifice *** can be seen from the simulated flow field that the geometry of orifice had little effect on the overall range and velocity distribution of the contributing flow region in front of the orifice,and the energy dissipation in front of the orifice still could be calculated by the hemisphere *** may help to understand that the difference of mechanical energy losses in orifice flow appears after flowing into the orifice.

关键词：孔流系数孔几何形状计算流体力学

POSITIVE SOLUTIONS OF NONLINEAR FOURTH-ORDER SINGULAR BOUNDARY VALUE PROBLEMS

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Annals of Differential Equations 2007年第3期23卷 288-296页

作者： Lü Haiyan liu yansheng Dept. of Math. Shandong University Jinan 250100 Dept. of Math. Shandong Normal University dinah 250014

By constructing a special cone and using the fixed point theorem of cone expansion and compression, this paper investigates fourth-order singular boundary value problems with sublinear effect and presents some necessary and sufficient conditions for existence of C2 or C3 positive solutions. Further, some examples are given concerning the applications of our main results.

关键词： boundary value problem fixed point positive solution singularity cone