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Prediction of Grain Size for Blade Precision Forging Process under Thermo-Mechanical Coupling

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Journal of Materials Science & Technology 2003年第Z1期19卷 156-158页

作者： he YANG yuli LIU Wang CAI Mei ZHAN College of Materials Science and Engineering Northwestern Polytechnical University Xi′an 710072 China College of Materials Science and Engineering Northwestern Polytechnical University Xi′an 710072 China College of Materials Science and Engineering Northwestern Polytechnical University Xi′an 710072 China College of Materials Science and Engineering Northwestern Polytechnical University Xi′an 710072 China

Blade precision forging is a high temperature and large plastic deformation process. Interaction of deformation andheat conduction results in producing large temperature unevenness inside the billet. The unevenness has a greateffect on the mechanical property and microstructure of the forged blade. However, internal quality of the blade isdecided by its microstructure, it is necessary to conduct a research on the microstructure of the blade forging *** a blade with a tenon as an object, its precision forging process is simulated and analyzed using a 3D coupledthermo-mechanical FEM code. And based on the prediction model of Ti-6Al-4V presented by the predecessor, astudy of the evolution of grain size in the forging process is made. The distribution characteristics of grain size intypical sections are obtained under various deformation degrees. This study may provide a base for designing theblade forging process and working out its parameters.

关键词： Blade, Precision forging, Grain size, Prediction

Enantioselective NiH-Catalyzed Reductive Hydrofunctionalization of Alkenes

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Chinese Journal of Chemistry 2022年第5期40卷 651-661页

作者： yuli he Jian Chen Xiaoli Jiang Shaolin Zhu State Key Laboratory of Coordination Chemistry Chemistry and Biomedicine Innovation Center(ChemBIC)Jiangsu Key Laboratory ofAdvanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjingJiangsu210093 China

Enantioselective NiH-catalyzed reductive hydrofunctionalization of olefins has attracted much attention in recent *** simple chiral ligands,a wide array of functionalized olefins and electrophiles can undergo diverse transformations to afford hydrofunctionalized products,regio-and *** processes avoid the prior preparation of organometallic reagents,and can construct a stereogenic center at a carbon originating either from the olefin or from the *** review discusses the background,major progress and mechanistic investigations in this reaction.

关键词： Asymmetric catalysis Nicke catalysis Nickel hydride Hydrofunctionalization Alkene

Biomolecular Preservation of Miocene Fossil Liquidambar from Tiantai,China and Clarkia,USA:Implications for Palaeoenvironmental Study

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Acta Geologica Sinica(English Edition) 2015年第4期89卷 1076-1087页

作者： XIAO Liang YANG Hong he yuli he Wenlong LI Xiangchuan GUO Junfeng HUI Kaixuan College of Earth Science and Resources and Key Laboratory of Western Mineral Resources and Geological Engineering Ministry of EducationChang’an University Laboratory of Terrestrial Environments Department of Science and TechnologyCollege of Arts and SciencesBryant University School of Earth Sciences and Key Laboratory of Mineral Resources in Western China (Gansu Province) Lanzhou University College of Geology and Environment Xi’an University of Science and Technology

Biomolecular characteristics of fossil Liquidambar from the Miocene Shengxian Formation, Tiantai, Zhejiang province in eastern China and Miocene Clarkia sediment, Idaho, U.S.A., are obtained by means of Pyrolysis-Gas chromatography-Mass spectrometry analysis （Py-GC-MS）. Their modern equivalent （Liquidambarformosana） collected from Nanjing, eastern China, is also analyzed for comparison. The total ion chromatograms （TIC） of modern L. formosana leaves shows abundant pyrolysates of iignin, polysaccharide, aliphatic acid, and amino acid. However, only one polysaccharide molecule, i.e., levoglucosan, is retained in fossil Liquidambar leaves from the two Miocene sites with the Tiantai specimen possessing higher intensity. As expected, some lignin pyrolysates including benzene, phenol, guaiacol, vinylphenol and their derivatives, are detected in Miocene Tiantai L. miosinica. However, the lignin components with large molecular weight other than benzene and phenol compounds, are absent in Miocene Clarkia L. pachyphyllum. Abundant pristene and homologous series of n-alk-l-ene/n-alkane pairs with a long retention time are shown in pyrograms of both Tiantai and Clarkia fossils. Based upon our Py-GC-MS data, the molecular preservation in these Liquidambar leaf samples can be ranked as the following （from high to low quality respectively）： modern sample 〉Tiantai sample 〉Clarkia sample. Vinyl phenol, an important compound, is present in modern and Tiantai Liquidambar leaves, while absent in Clarkia sample, implying that vinyl phenol may be sourced from lignin for Liquidambar leaves. Our data support the hypothesis of in situ polymerization for the origin of long-chain homologous series of n-alk-l-ene/n- alkane pairs as leaf alteration products. Our data have implications of the impact of leaf degradation toward biases for palaeoenvironmental reconstruction using stable carbon isotope of fossil plants, and suggest the importance of evaluating molecular preservation of fossil leaf t

关键词： Liquidambar Py-GC-MS Miocene Biomolecules palaeoenvironment

Quercus yangyiensis sp. nov. from the Late Pliocene of Baoshan, Yunnan and Its Paleoclimatic Significance

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Acta Geologica Sinica(English Edition) 2014年第3期88卷 738-747页

作者： he yuli LI Na WANG Zixi WANG Haofei YANG Guolin XIAO Liang WU Jingyu SUN Bainian School of Earth Sciences and Key Laboratory of Mineral Resources in Western China Lanzhou University School of Earth and Resource Sciences Chang'an University

A new Quercus （Fagaceae） morphospecies is described based on well-preserved fossil *** fossils were collected from Yangyi Formation of the Upper Pliocene at the Yangyi coalmine,Baoshan,western Yunnan,*** of the microstructure of mesophyll tissue are preserved because lithification of the fossils was not *** fossil laminas possess typical characteristics of Quercus ***：quite thick and coriaceous cuticle; secondary veins bifurcating near the margin in the middle and top of the leaf; and upper epidermis with adaxial *** on a detailed morphological and anatomical comparison with all living and fossil species of Quercus ***,the fossil leaves prove to be different in their sparse and garland-shaped multicellular trichomes on the lower epidermis,and so it is described as a new species Quercus yangyiensis he,Li et Sun *** much sparser trichomes of our fossils compare well with those of living Quercus *** and indicate a more humid climate during the deposition of the Yangyi Formation in the Late Pliocene.

关键词： Paleobotany fossil leaf cuticle Quercus paleoclimate Pliocene Yunnan

Recent Advances in Mn,Fe,Co,and Ni-Catalyzed Organic Reactions

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CCS Chemistry 2024年第3期6卷 537-584页

作者： Lu-Jie Li yuli he Yunhui Yang Jun Guo Zhan Lu Congyang Wang Shaolin Zhu Shou-Fei Zhu College of Chemistry Nankai UniversityTianjin 300071 School of Chemistry and Chemical Engineering Nanjing UniversityNanjingJiangsu Province 210093 Institute of Chemistry Chinese Academy of Sciences and University of Chinese Academy of SciencesBeijing 100190 Department of Chemistry Zhejiang UniversityHangzhouZhejiang Province 310058

This paper reviewed the recent research progress of organic reactions catalyzed by four typical earthabundant and 3d metal catalysts:Mn,Fe,Co,and Ni complexes and mainly focused on the reactions in which these 3d metal catalysts exhibited obvious advantages over other *** mechanism that makes these 3d metal catalysts show unusual properties is another focus of this *** outlook on 3d metal complexes-catalyzed organic reactions was also considered.

关键词： Earth-abundant metal catalysts sustainable organic synthesis structure-function relationships organometallic intermediates hydrocarbon transformations

新型手性Quinim配体促进的镍催化的非活化烯烃不对称1,2-胺甲酰基-烷基双官能团化

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有机化学 2020年第12期40卷 4377-4379页

作者：何玉立朱少林南京大学化学化工学院南京210093

γ-内酰胺是药物分子和天然产物的一类重要核心骨架[1],其中常见的手性α-烷基取代的γ-内酰胺具有良好的生物活性(图1).该类化合物的手性合成传统上依赖于步骤繁琐的手性辅基策略,近期张万斌[2]和丁奎岭[3]课题组分别报道了不对称氢化... 详细信息

γ-内酰胺是药物分子和天然产物的一类重要核心骨架[1],其中常见的手性α-烷基取代的γ-内酰胺具有良好的生物活性(图1).该类化合物的手性合成传统上依赖于步骤繁琐的手性辅基策略,近期张万斌[2]和丁奎岭[3]课题组分别报道了不对称氢化的策略构建其中一类α-苄基取代的γ-内酰胺,Cramer课题组[4]报道了镍催化的不对称氢胺甲酰策略构建其中一类α-甲基取代的γ-内酰胺,然而通用的不对称催化策略到目前为止仍然没有实现.

关键词：不对称催化不对称氢化镍催化天然产物烷基取代手性合成药物分子策略构建

镍氢催化炔酮的不对称反式环化反应构建环内杂环烯丙醇

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有机化学 2022年第2期42卷 659-661页

作者：何玉立朱少林南京大学化学化工学院南京210093

烯丙醇类化合物是于天然产物和药物分子中的重要骨架[1-2].过渡金属催化的炔烃和酮类化合物的还原偶联反应是构建烯丙醇类化合物直接的方法之一[2].镍催化炔酮的还原偶联反应可以成功构建环状烯丙醇,并作为核心步骤多次应用于天然产物... 详细信息

烯丙醇类化合物是于天然产物和药物分子中的重要骨架[1-2].过渡金属催化的炔烃和酮类化合物的还原偶联反应是构建烯丙醇类化合物直接的方法之一[2].镍催化炔酮的还原偶联反应可以成功构建环状烯丙醇,并作为核心步骤多次应用于天然产物的合成之中[3-5].前期,中国科学院上海有机化学研究所汤文军课题组和内蒙古大学刘国都课题组[6-7]都使用Ni(COD);和手性膦配体,实现了分子内炔酮的不对称还原环化反应。

关键词：还原偶联反应手性膦配体不对称还原环化反应天然产物烯丙醇过渡金属催化炔酮

E-cadherin expression and its clinical significance in 41 cases of spinal plasma cell myeloma

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Journal of Medical Colleges of PLA(China) 2009年第1期24卷 56-62页

作者： Wang Liangzhe Liu Huimin he Jin Li yuli Xu Yi Chen Bing Department of Pathology ChangZheng Hospital Second Military Medical University Shanghai 200003 China

Objective： To investigate the expression level of E-cadherin in spinal plasma cell myeloma and its relationship with the clinicopathological indexes of spinal plasma cell myeloma. Methods： The expression of E-cadherin was detected in 41 cases of spinal plasma cell myeloma and 14 cases of simple bone cysts by using S-P （streptavidin-perosidase） immunohistochemical staining. The relationship between E-cadherin expression and the clinicopathological features was analyzed. Results： In spinal plasma cell myelomas, the positive expression rate of E-cadherin （46.34%） was higher than that in simple bone cyst tissues （all negative）（P〈0.01）. And the expression of E-cadherin had no obvious relationship with patients＇ age, gender, clinical classification or M-component （P〉0.05）, but had relationship with the classification of light chain. The expression rate in lambda chain subgroup was lower than that in the others （P〈0.05）. We also found the E-cadherin negative patients had a higher overall survival rate than those who had strong E-cadherin expression （P〈0.05）. Conclusion： E-cadherin expressed higher in spinal plasma cell myelomas than in simple bone cyst tissues and its expression had relationship with the light chain classification in spinal plasma cell myeloma. The patients with no stain of E-cadherin may have a poor prognosis. Detecting the type of light chain associated with expression of E-cadherin might be helpful in evaluating the outcome of spinal PCM patients.

关键词： Myeloma E-cadherin Spine Osteoclasia Immunohistochemistry

算法推荐语境下短视频平台的版权过滤义务研究

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中南财经政法大学研究生论丛 2023年第2期 128-136页

作者：何羽丽中南财经政法大学知识产权学院湖北武汉430073

在智能时代的今天,短视频平台利用算法技术与个性化分析工具实现了视频内容的精准推送、提升了信息传播效果,但同时也与早前平台“技术无价值”论的定位相去甚远。短视频平台更强的风险预测和管理能力成为提高注意义务的理论逻辑原点,... 详细信息

在智能时代的今天,短视频平台利用算法技术与个性化分析工具实现了视频内容的精准推送、提升了信息传播效果,但同时也与早前平台“技术无价值”论的定位相去甚远。短视频平台更强的风险预测和管理能力成为提高注意义务的理论逻辑原点,而以技术中立为前提的避风港原则在算法推荐语境下呈现出了不适应的局面。基于版权事前保护立法缺位、注意义务裁判标准的适用混乱现象及过滤算法技术的完善,过滤义务的构建已具备理论必要性与现实可能性,有必要明确其非强制性与非一般性的民事注意义务性质,进而设置合理的义务主体类型与过滤的具体程序,尝试构筑适于中国文化发展样态和技术发展水平的短视频版权过滤义务规则,从而实现平台版权治理的协同与优化。

关键词：算法推荐版权过滤义务短视频避风港原则