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Active sub-reflector research for a large radio telescope

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Research in Astronomy and Astrophysics 2020年第1期20卷 69-76页

作者： Jin-Qing Wang Rong-Bin Zhao yong-chen jiang Zheng-Xiong Sun Lin-Feng Yu Li Fu Qin-Hui Liu Wei-Min Zheng Zhi-Qiang Shen Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China Key Laboratory of Radio Astronomy Chinese Academy of SciencesNanjing 210008China Shanghai Key Laboratory of Space Navigation and Positioning Techniques Shanghai 430074China

This paper proposes an active sub-reflector suitable for large radio telescopes,which can compensate both of the deformation of the main reflector and sub-reflector position *** mathematical formula of the main reflector deformation compensated by the sub-reflector is deduced based on Cassegrain and Gregory antenna *** position of the sub-reflector is adjustable to compensate for defocusing errors on high and low elevations,which are mainly caused by the deformation of the sub-reflector supporting *** this paper,the method of obtaining the optimum position of the sub-reflector from the aperture phase by the interferometric method is *** actual measurement is verified on the Tianma 65 m radio telescope,which provides a new way to diagnose the position error of the sub-reflector.

关键词： radio telescope deformable sub-reflector model holography phase

Toward understanding the role of genomic repeat elements in neurodegenerative diseases

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Neural Regeneration Research 2025年第3期20卷 646-659页

作者： Zhengyu An Aidi jiang Jingqi chen Institute of Science and Technology for Brain-Inspired Intelligence Fudan UniversityShanghaiChina MOE Frontiers Center for Brain Science Fudan UniversityShanghaiChina MOE Key Laboratory of Computational Neuroscience and Brain-Inspired Intelligence Fudan UniversityShanghaiChina Zhangjiang Fudan International Innovation Center ShanghaiChina

Neurodegenerative diseases cause great medical and economic burdens for both patients and society;however, the complex molecular mechanisms thereof are not yet well understood. With the development of high-coverage sequencing technology, researchers have started to notice that genomic repeat regions, previously neglected in search of disease culprits, are active contributors to multiple neurodegenerative diseases. In this review, we describe the association between repeat element variants and multiple degenerative diseases through genome-wide association studies and targeted sequencing. We discuss the identification of disease-relevant repeat element variants, further powered by the advancement of long-read sequencing technologies and their related tools, and summarize recent findings in the molecular mechanisms of repeat element variants in brain degeneration, such as those causing transcriptional silencing or RNA-mediated gain of toxic function. Furthermore, we describe how in silico predictions using innovative computational models, such as deep learning language models, could enhance and accelerate our understanding of the functional impact of repeat element variants. Finally, we discuss future directions to advance current findings for a better understanding of neurodegenerative diseases and the clinical applications of genomic repeat elements.

关键词： Alzheimer's disease ataxia deep learning long-read sequencing neurodegeneration neurodegenerative diseases Parkinson's disease repeat element structural variant

Microstructural evolution during the progressive transformation-induced plasticity effect in a Fe-0.1C-5Mnmedium manganese steel

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 369-379页

作者： Mei Zhang Wenhao Li Yangfei chen Yang jiang Xiaofei Guo Han Dong School of Materials Science and Engineering Shanghai UniversityShanghai 200444China State Key Laboratory of Advanced Special Steel Shanghai UniversityShanghai 200444China

The microstructural evolution of a cold-rolled and intercritical annealed medium-Mn steel(Fe-0.10C-5Mn)was investigated during uniaxial tensile ***-situ observations under scanning electron microscopy,transmission electron microscopy,and X-ray diffraction analysis were conducted to characterize the progressive transformation-induced plasticity process and associated fracture initiation *** findings were discussed with the local strain measurements via digital image *** results indicated that Lüders band formation in the steel was limited to 1.5%strain,which was mainly due to the early-stage martensitic phase transformation of a very small amount of the less stable large-sized retained austenite(RA),which led to localized stress concentrations and strain hardening and further retardation of *** small-sized RA exhibited high stability and progressively transformed into martensite and contributed to a stably extended Portevin-Le Chatelier *** volume fraction of RA gradually decreased from 26.8%to 8.2%prior to *** the late deformation stage,fracture initiation primarily occurred at the austenite/martensite and ferrite/martensite interfaces and the ferrite phase.

关键词： medium-Mn steel retained austenite progressive transformation-induced plasticity effect local strain fracture initiation

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滚珠丝杠副刚度影响因素及试验研究

振动与冲击 2013年第11期32卷 70-74页

作者：陈勇将汤文成王洁璐东南大学机械工程学院南京211189

为提高滚珠丝杠副静态与动态分析精度,利用滚珠丝杠副中丝杠滚道的力与力矩平衡方程,并考虑变化的接触角及接触变形影响,建立联合载荷作用下精确的滚珠丝杠副刚度数学模型。并分析滚珠丝杠副刚度影响因素及规律,结果表明,滚珠丝杠副刚... 详细信息

为提高滚珠丝杠副静态与动态分析精度,利用滚珠丝杠副中丝杠滚道的力与力矩平衡方程,并考虑变化的接触角及接触变形影响,建立联合载荷作用下精确的滚珠丝杠副刚度数学模型。并分析滚珠丝杠副刚度影响因素及规律,结果表明,滚珠丝杠副刚度随轴向、径向载荷的增大而变大,随倾覆力矩增加而减小;增大导程与减小滚道曲率比可提高滚珠丝杠副刚度;轴向刚度随轴向载荷、导程和滚道曲率比的改变所受影响最大,角刚度主要受径向载荷和倾覆力矩的影响,径向刚度受载荷与结构参数影响较小。通过与滚珠丝杠副轴向静刚度测量结果比较,所建模型合理、可靠。

关键词：滚珠丝杠副联合载荷赫兹接触刚度

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铂类抗肿瘤配合物的研究进展

无机化学学报 2005年第8期21卷 1115-1121页

作者：崔凯王联红陈永江苟少华南京大学配位化学国家重点实验室南京210093

铂类药物是当前一类主要的抗肿瘤药物。本文结合我们的研究工作综述了2000年以来文献报道的新型抗肿瘤铂类配合物的研究进展。按铂原子的价态、配体基团的结构特征、配位原子及中心原子的个数将其分为:含有生物活性基团的铂髤配合物;具... 详细信息

铂类药物是当前一类主要的抗肿瘤药物。本文结合我们的研究工作综述了2000年以来文献报道的新型抗肿瘤铂类配合物的研究进展。按铂原子的价态、配体基团的结构特征、配位原子及中心原子的个数将其分为:含有生物活性基团的铂髤配合物;具有空间位阻的铂髤配合物;以P和S原子作为配位原子的铂(II)配合物;多核铂髤配合物;其他含有小分子配体的铂髤配合物和四价铂类配合物六类,并进行了总结。

关键词：抗肿瘤药物铂(Ⅱ)配合物铂(Ⅳ)配合物

Surface micro-arrays enhancing electromagnetic interference shielding of polydimethylsiloxane/multiwalled carbon nanotubes nanocomposites

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Nano Research 2025年第1期18卷 508-519页

作者： Ke jiang Zhi chen Ji Yu chen Zheng Shan Huang Ming Wang Chongqing Key Laboratory of Soft-Matter Material Manufacturing School of Chemistry and Chemical EngineeringSouthwest UniversityChongqing 400715China School of Mechanics Civil Engineering and ArchitecturesNorthwestern Polytechnical UniversityXi’an 710072China Jieyang Branch of Chemistry and Chemical Engineering Guangdong Laboratory(Rongjiang Laboratory) Jieyang 515200China

Herein,the electromagnetic shielding performance of surface concave-convex(SC)and zig-zag micro-arrays was studied by using a simulation prediction and a three-dimensional(3D)printing custom ***,surface stripe concaveconvex(SSC)and surface cylindrical concave-convex(SCC)micro-arrays with or without zig-zag micro-arrays are designed,and their shielding performance is simulated in multi-bands(C-,X-band).The multiwalled carbon nanotubes/polydimethylsiloxane composites(MWCNT/PDMS)with different SC structures and different electrical conductivity are molded in acrylonitrile-butadiene-styrene copolymer(ABS)molds which are printed by a 3D *** results show that the electromagnetic interference shielding effectiveness(EMI SE)of the samples can be enhanced by constructing the SC micro-arrays with zig-zag micro-arrays,and improving with the increase of conductivity and *** addition,the shielding mechanism of the SC-MWCNT/PDMS composites is investigated and discussed by an electromagnetic simulation.

关键词： surface micro-arrays electrical properties electromagnetic interference(EMI)shielding three-dimensional(3D)printing

新型Co(salen)化合物的合成,表征及其硫醚不对称氧化反应(英文)

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无机化学学报 2005年第6期21卷 842-845,F007页

作者：诸海滨袁阜平陈永江苟少华南京大学配位化学国家重点实验室南京210093

合成并表征了新的Co(salen)化合物(2a^2c和3a^3c)。手性CoⅡ(salen)化合物2a^2c在硫醚的不对称氧化反应中显示了中等的反应活性,但只获得了较低对映选择性(8%~21%ee),而手性CoⅢ(salen)化合物3a^3c在该反应中没有反应活性。通过研究整... 详细信息

合成并表征了新的Co(salen)化合物(2a^2c和3a^3c)。手性CoⅡ(salen)化合物2a^2c在硫醚的不对称氧化反应中显示了中等的反应活性,但只获得了较低对映选择性(8%~21%ee),而手性CoⅢ(salen)化合物3a^3c在该反应中没有反应活性。通过研究整个配体的构象影响对化合物的低对映选择性进行了讨论。

关键词： salen 钴化合物不对称氧化硫醚合成表征催化活性

基于Pro/Toolkit的通用参数修改模块的设计

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机械设计与制造 2010年第2期 77-79页

作者：陈勇将徐幼林南京林业大学机械电子工程学院南京210037

目前常见的参数设计二次开发只能针对具体的零件,没有通用性与灵活性,零件变化时就必须重新开发。利用Pro/E的二次开发工具Pro/Toolkit,结合VC开发出能够适应任何零件的通用参数修改模块。

关键词：参数化技术二次开发 Pro/Toolkit

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血清PSA密度变化对前列腺癌的诊断价值

国际医药卫生导报 2008年第22期14卷 16-18页

作者：陈永绛罗定市人民医院泌尿外科广东罗定527200

目的探讨前列腺特异抗原密度（PSAD）变化对前列腺癌的诊断价值。方法对初次活检阴性的372例患者进行随访，其中72例重复穿刺活检，确诊前列腺癌25例；对重复活检患者的PSA、PSAD等临床资料进行统计学分析。结果配对t检验显示，前列腺... 详细信息

目的探讨前列腺特异抗原密度（PSAD）变化对前列腺癌的诊断价值。方法对初次活检阴性的372例患者进行随访，其中72例重复穿刺活检，确诊前列腺癌25例；对重复活检患者的PSA、PSAD等临床资料进行统计学分析。结果配对t检验显示，前列腺癌末次穿刺前的PSA、PSAD较首次穿刺前的升高，差异有统计学意义。以PSA末-PSA首〉0筛选前列腺癌，其敏感性、特异性、阳性预测值分别为84．0％、40．4％、42．9％；而以PSAD末-PSAD首〉0筛选前列腺癌，其敏感性、特异性、阳性预测值分别为84．0％、55．3％、50．0％。结论对前列腺癌可疑者应动态观察PSAD变化；以PSAD动态升高来指导穿刺活检，可以明显提高阳性率，减少不必要的穿刺。

关键词：前列腺癌活检前列腺特异抗原前列腺特异抗原密度