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Chinese Chemical Letters 2014年第1期25卷 65-68页

作者： Chun Zhan You-Yu Jiang Ming-Yan Yang Lu-Hua Lu sheng-qiang xiao State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology WUT-USG Joint Laboratory of Advanced Optoelectronic Materials and Devices Wuhan University of Technology Center for Chemical and Materials Engineering Wuhan University of Technology

A facile procedure for the synthesis ofdithieno[5,6-b：11,12-b＇]coronene-2,3,8,9-tetracarboxylic tetra（2- ethylhexyl）ester （DTCTI＇E-EH） from readily available perylene-3,4,9,10-tetracaroboxylic dianhydride is described. The electronic properties of DTCTTE-EH were elucidated on the basis of UV-vis spectra, emission spectrum and electrochemical measurement, which demonstrate that DTCTTE is a new class of components for promising semiconducting materials.

关键词： Polycyclic aromatic molecules Coronene tetracarboxylic tetraester Semiconductor Optoelectronic property

Micro-Climate Evaluation System in Thermal Mines

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Journal of China University of Mining and Technology 2006年第1期16卷 1-4页

作者： YANG sheng-qiang OU xiao-ying CHENG Jian-wei WANG Yi-jiang YU Bao-hai School of Mineral and Safety Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

A fuzzy evaluation method was used to evaluate the microclimate in thermal mines. A theoretical model of a microclimate evaluation system was designed and membership functions of the evaluation indices in the system were established. An analytical hierarchy process (AHP) was used to analyze the weight of the evalua- tion indices and their methods of calculation. Software for this evaluation system was developed and used for the evaluation of the microclimate of 714 sections in a mine. It is shown that the evaluation results correspond com- pletely with the actual situation. This evaluation system and the software can be applied in thermal mines.

关键词： membership grade weight fuzzy evaluation method thermal mine

Effects of the extrusion parameters on microstructure,texture and room temperature mechanical properties of extruded Mg-2.49Nd-1.82Gd-0.2Zn-0.2Zr alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 136-146页

作者： Chenjin Zhang Guangyu Yang Lei xiao Zhiyong Kan Jing Guo qiang Li Wanqi Jie State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China College of Materials Science and Engineering Fuzhou UniversityFuzhou 350108China College of Chemistry and Environmental Science Qujing Normal UniversityQujing 655011China

Microstructure,texture,and mechanical properties of the extruded Mg-2.49Nd-1.82Gd-0.2Zn-0.2Zr alloy were investigated at different extrusion temperatures(260 and 320℃),extrusion ratios(10:1,15:1,and 30:1),and extrusion speeds(3 and 6 mm/s).The experimental results exhibited that the grain sizes after extrusion were much finer than that of the homogenized alloy,and the second phase showed streamline distribution along the extrusion direction(ED).With extrusion temperature increased from 260 to 320℃,the microstructure,texture,and mechanical properties of alloys changed *** dynamic recrystallization(DRX)degree and grain sizes enhanced as the extrusion ratio increased from 10:1 to 30:1,and the strength gradually decreased but elongation(EL)*** the extrusion speed increased from 3 to 6 mm/s,the grain sizes and DRX degree increased significantly,and the samples presented the typical-rare-earth(RE)*** alloy extruded at 260℃ with extrusion ratio of 10:1 and extrusion speed of 3 mm/s showed the tensile yield strength(TYS)of 213 MPa and EL of 30.6%.After quantitatively analyzing the contribution of strengthening mechanisms,it was found that the grain boundary strengthening and dislocation strengthening played major roles among strengthening *** results provide some guidelines for enlarging the industrial application of extruded Mg-RE alloy.

关键词： Mg-rare earth alloys extrusion temperature extrusion ratio extrusion speed strengthening mechanisms

A novel stepwise thresholding for fuzzy image segmentation

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Chinese Journal of Biomedical Engineering(English Edition) 2001年第1期10卷 1-12页

作者： HE xiao-hai, LUO Dai-sheng, WU xiao-qiang, JIANG Li, TENG Qi-zhi, Tao De-yuan Institute of Electronics and Information, Sichuan University, Chengdu 61064, China Institute of Electronics and Information Sichuan University Chengdu 61064 China

A novel stepwise thresholding method for fuzzy image segmentation is proposed. Unlike the published iterative or recursive thresholding mehtods, this method segments regions into sub-regions iteratively by increasing threshold value in a stepwise manner, based on a preset intensity homogeneity criteria. The method is particularly suited to segmentation of the laser scanning confocal microscopy (LSCM) images, computerised tomography (CT) images, magnetic resonance (MR) images, fingerprint images, etc. The method has been tested on some typical fuzzy image data sets. In this paper, the novel stepwise thresholding is first addressed. Next a new method of region labelling for region extraction is introduced. Then the design of intensity homogeneity segmentation criteria is presented. Some examples of the experiment results of fuzzy image segmentation by the method are given at the end.

关键词： fuzzy image, image processing, image segmentation, iterative thresholding, region labelling, intensity homogeneity

577nm全视网膜光凝术对糖尿病视网膜病变黄斑的影响

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国际眼科杂志 2015年第7期15卷 1259-1260页

作者：贾趁霞肖胜强中国河南省长垣县人民医院眼科 453400

目的:探讨577nm全视网膜光凝术对糖尿病视网膜病变黄斑中心凹厚度的影响。方法:应用optovue光学相干断层扫描仪分析37例45眼增殖前期糖尿病视网膜病变(preproliferative diabetic retinopathy,PPDR)和增殖期糖尿病视网膜病变(proliferat... 详细信息

目的:探讨577nm全视网膜光凝术对糖尿病视网膜病变黄斑中心凹厚度的影响。方法:应用optovue光学相干断层扫描仪分析37例45眼增殖前期糖尿病视网膜病变(preproliferative diabetic retinopathy,PPDR)和增殖期糖尿病视网膜病变(proliferative diabetic retinopathy,PDR)患者接受577nm全视网膜光凝术前和术后1,3,6mo黄斑中心凹视网膜神经上皮层的厚度。结果:全视网膜光凝术后1,3mo,黄斑中心凹视网膜神经上皮层的厚度与术前相比较明显增厚,两者比较具有统计学差异(P0.05)。结论:577nm全视网膜光凝术能够引起糖尿病患者黄斑中心凹神经上皮层厚度一过性增加,术后6mo时逐渐恢复到术前的水平。

关键词：糖尿病视网膜病变黄斑 577nm 全视网膜光凝术光学相干断层扫描

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多分支水平井压力系统分析模型

石油学报 2003年第6期24卷 81-86页

作者：黄世军程林松李秀生雷小强石油大学石油天然气工程学院北京102249 中国石油勘探开发研究院北京100083

基于流体力学相关理论,采用整体压力系统分析方法,考虑到多分支水平井各分支在主井眼井底的相互干扰,建立了以上井眼井底为求解节点、从油藏到井口的多分支水平井压力系统分析模型。在该模型中,综合考虑了多分支水平井中的油藏渗流、水... 详细信息

基于流体力学相关理论,采用整体压力系统分析方法,考虑到多分支水平井各分支在主井眼井底的相互干扰,建立了以上井眼井底为求解节点、从油藏到井口的多分支水平井压力系统分析模型。在该模型中,综合考虑了多分支水平井中的油藏渗流、水平段多相管流、弯曲段和垂直段多相管流以及采油举升方式,推导并提出了模型的求解方法,并编制了相应的计算机程序。利用压力系统分析模型,可求解多分支水平井的协调产量和协调流压,以及多分支水平井在协调点的产量和各分支水平段沿程压力分布及产量分布。对裸眼完井方式下三分支水平井自喷采油时的协调产量和协调压力实例模拟计算结果表明,该模型适用于求解应用前景广阔的多分支水平井不同举升方式下协调产量及协调压力。

关键词：多分支水平井节点分析模型压力分布产量分布压力系统采收率压降

clap式冰刀蹬冰动作特点对速滑专项力量训练理念的启示

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天津体育学院学报 2004年第2期19卷 15-17页

作者：陈民盛张强覃晓红东北师范大学体育学院长春130024

通过对2002年世界速滑锦标赛优秀运动员弯道蹬冰技术动作的分析后认为,clap式冰刀与传统冰刀蹬冰过程中肌群工作方式存在着明显的不同。clap式冰刀蹬冰动作遵循大环节带动小环节,由上至下的关节发力顺序规律;而传统式冰刀则是以臀大肌... 详细信息

通过对2002年世界速滑锦标赛优秀运动员弯道蹬冰技术动作的分析后认为,clap式冰刀与传统冰刀蹬冰过程中肌群工作方式存在着明显的不同。clap式冰刀蹬冰动作遵循大环节带动小环节,由上至下的关节发力顺序规律;而传统式冰刀则是以臀大肌和股四头肌的近固定工作与腓肠肌的远固定工作之合力实现两侧牵拉式伸膝动作。并且提出对速滑蹬冰技术动作的爆发力程度应重新审视的观点。由于肌群工作方式的异同性提示在力量训练理念上,更应加强速度力量性训练手段的选用,提高对肌腱的训练效果,重视专项力量训练对神经系统的作用功效。

关键词： clap 式冰刀蹬冰动作专项力量训练理念

郑氏“热补针法”治疗脾胃虚寒型胃痛的疗效观察

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上海针灸杂志 2017年第9期36卷 1038-1040页

作者：黄继升谢小强天水市中西医结合医院天水741020 天水市麦积区中医医院天水741020

目的观察热补针法治疗脾胃虚寒性胃痛的临床疗效。方法将40例脾胃虚寒型胃痛患者按照就诊顺序采用随机数字表法分为治疗组和对照组,每组20例。对照组采用捻转补法治疗,治疗组采用热补针法治疗。观察两组治疗前后VAS评分变化,并比较临床... 详细信息

目的观察热补针法治疗脾胃虚寒性胃痛的临床疗效。方法将40例脾胃虚寒型胃痛患者按照就诊顺序采用随机数字表法分为治疗组和对照组,每组20例。对照组采用捻转补法治疗,治疗组采用热补针法治疗。观察两组治疗前后VAS评分变化,并比较临床疗效。结果两组治疗后VAS评分与同组治疗前比较,差异均有统计学意义(P<0.05),两组治疗后VAS评分比较,差异有统计学意义(P<0.05),两组治疗前后VAS评分差值比较,差异有统计学意义(P<0.05)。治疗组总有效率为95.0%,对照组为60.0%,两组比较差异有统计学意义(P<0.05),两组临床疗效和治疗后2星期的复发率比较,差异有统计学意义(P<0.05)。结论热补针法治疗脾胃虚寒型胃痛临床疗效肯定,复发率低。

关键词：针刺疗法热补针法胃脘痛 VAS

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基于三维固定裂缝模型的混凝土开裂数值模拟

中国农村水利水电 2017年第2期 130-134页

作者：王碗琴强晟郭晓娜周兰庭河海大学水利水电学院南京210098 南水北调中线干线工程建设管理局北京100038

基于三维固定裂缝模型基本理论,编制Fortran程序,对经典3点弯曲梁在集中力作用下的开裂问题进行数值模拟。固定裂缝模型基于断裂能守恒,通过调整混凝土应力~应变软化曲线来适应不同大小的网格模型。将计算所得的特征点的应力~应变曲线... 详细信息

基于三维固定裂缝模型基本理论,编制Fortran程序,对经典3点弯曲梁在集中力作用下的开裂问题进行数值模拟。固定裂缝模型基于断裂能守恒,通过调整混凝土应力~应变软化曲线来适应不同大小的网格模型。将计算所得的特征点的应力~应变曲线和假定的应力~应变曲线进行对比,结果表明不同网格模型的断裂能基本一致,编制的程序正确,固定裂缝模型在一定程度上能够克服网格敏感性问题。对同一网格模型选用不同断裂能参数进行模拟,比较在相同荷载条件下的荷载~位移曲线和应变包络图,结果比较符合实际情况和基本理论,表明固定裂缝模型能较好地模拟出裂缝的开展过程。

关键词：断裂力学固定裂缝模型断裂能混凝土开裂应力~应变曲线

De novo synthesis of atropisomeric benzofurans via Cu/SPDO complex catalyzed asymmetric formal [3 + 2] annulation

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Science China Chemistry 2025年第1期 174-180页

作者： Fan-xiao Meng Xing-Yu Wang Ka Lu Ju-Song Yang Fu-Min Zhang Ai-Jun Ma Bao Du Yong-qiang Tu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University School of Chemistry and Chemical Engineering Shanghai Jiao Tong University School of Biotechnology and Health Sciences Wuyi University

Herein, the de novo synthesis of atropisomeric benzofurans through the Cu/spirocyclic-pyrrolidine-oxazoline(SPDO) complex catalyze asymmetric formal [3 + 2] cycloaddition between quinones and ynamides is explored, producing a range of structurally diverse axially chiral benzofurans in satisfactory yields with good to excellent enantioselectivities. Furthermore, density functional theory calculations were applied to explain the possible reaction mechanism.

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