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Chinese Journal of Chemistry 2015年第2期33卷 175-180页

作者： Yi liu zhan liu Yingde Cui School of Materials Science and Engineering Northwestern Polytechnical UniversityXi'anShaanxi 710072China Departmenl of Chemistry and Chemical Engineering Huaihua UniversityHuaihuaHunan 418000China Guangzhou Vocational College of Science and Technology GuangzhouGuangdong 510550China

A magnetic nano-supported Cu(I)catalyst was prepared and showed high activity for cyclization of ene-yne-ketone to synthesize *** catalyst was easily recovered from the reaction by using external magnets and reused 8 ... 详细信息

关键词： furans ene-yne-ketone magnetic nano-supported copper(I)catalyst cyclization

Microstructure refinement and work hardening in a machined surface layer induced by turning Inconel 718 super alloy

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International Journal of Minerals,Metallurgy and Materials 2018年第8期25卷 937-949页

作者： Xiao-ping Ren zhan-qiang liu School of Mechanical Engineering Shandong University Key Laboratory of High Efficiency and Clean Mechanical Manufacture Ministry of EducationShandong University

The microstructural changes in the machined surface layer of Ni-based super alloys essentially determine the final performance of the structural components of aerospace engines in which these alloys are *** this work,multiscale metallurgical observations using scanning electron microscopy,electron-backscatter diffraction microscopy,and transmission electron microscopy were conducted to quantitatively characterize the microstructure of the machined ***,to elucidate the factors that affect the formation of the refinement microstructure,the distributions of the deformation parameters(strain,strain rate,and temperature) in the machined subsurface were analyzed.A dislocation–twin interaction dynamic recrystallization mechanism for grain refinement during machining of Inconel 718 is ***,microhardness evolution induced by grain refinement in the machined surface is *** results suggest that the gradient microstructure and the work hardening can be optimized by controlling the cutting parameters during turning of Inconel 718.

关键词： grain refinement dislocation–twin interaction work hardening turning Inconel 718

Prediction of temperature field in machined workpiece surface during the cutting of Inconel 718 coated with surface-active media

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Advances in Manufacturing 2023年第3期11卷 378-389页

作者： Qing-An Yin zhan-Qiang liu Bing Wang School of Mechanical Engineering Shandong UniversityJinan 250061People's Republic of China Key National Demonstration Center for Experimental Mechanical Engineering Education/Key Laboratory of High Efficiency and Clean Mechanical Manufacture of MQE Jinan 250061People's Republic of China

The heat generated and accumulated on the machined surface of an Inconel 718 workpiece causes thermal damage during the cutting ***-active media with high thermal conductivity coated on the workpiece to be machined may have the potential to reduce the generation of cutting *** this study,a theoretical model for predicting the instantaneous machined surface temperature field is proposed for surface-active thermal conductive medium(SACM)-assisted cutting based on the finite element and Fourier heat transfer *** cutting experiments were performed to verify the results predicted using the proposed surface-temperature field *** SACMs with various thermal conductivities were used to coat Inconel 718 surface to be *** embedded into the workpiece were used to measure the cutting temperature at different points on the machined workpiece surface during the cutting *** experimental results were in agreement with the predicted temperatures,and the maximum error between the experimental results and predicted temperatures was approximately 9.5%.The cutting temperature on the machined surface decreased with an increase in the thermal conductivity of the *** graphene SACM with high thermal conductivity can effectively reduce the temperature from 542℃ to 402℃,which corresponds to a reduction of approximately 26%.The temperature reduction due to SACM decreases with an increase in the distance between the temperature prediction point and machined workpiece *** conclusion,the cutting temperatures on the machined workpiece surface can be reduced by coating with SACM.

关键词： Surface-active thermal conductive media(SACM) Finite element model Cutting heat Cutting temperature Inconel 718

Synthesis of new chiral 1,2,3,4-tetrahydroisoquinoline β-amino alcohols from L-DOPA

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Chinese Chemical Letters 2008年第11期19卷 1271-1273页

作者： Geng Xu zhan Zhu liu Institute of Materia Medica Peking Union Medical College ＆ Chinese Academy of Medical Science Beijing 100050 China

Four new chiral 1,2,3,4-tetrahydroisoquinoline-derived β-amino alcohols were synthesized from L-DOPA in good yields. The structures of the target compounds were confirmed by ^1H NMR, ^13C NMR and MS.

关键词： β-Amino alcohol Tetrahydroisoquinoline L-DOPA Pictet-Spengler reaction

Enantioselective addition of diethylzinc to aryl aldehydes catalyzed by 1,2,3,4-tetrahydroisoquinoline β-amino alcohol

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Chinese Chemical Letters 2010年第3期21卷 309-311页

作者： Geng Xu[a] zhan Zhu liu[a] [a] Key Laboratory of Bioactive Substances Resources Utilization of Chinese Herbal Medicine (Peking Union Medical College) Ministry of Education. Institute of Materia Medica Peking Union Medical College & Chinese Academy of Medical Sciences Beijing 100050 China

A highly effective,new chiral 1,2,3,4-tetrahydroisoquinoline catalyst 1 for the diethylzinc addition to aryl aldehydes has been *** 10 mol%of this chiral catalyst,secondary alcohols can be obtained in up to 87%yield a... 详细信息

关键词： β-Amino alcohol Tetrahydroisoquinoline Diethylzinc Asymmetric addition

Synthesis of new chiral 1,2,3,4-tertrahydroisoquinoline β-amino alcohol for asymmetric diethylzinc addition to aryl aldehydes(Ⅰ)

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Chinese Chemical Letters 2009年第12期20卷 1393-1396页

作者： Geng Xu zhan Zhu liu Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine (Peking Union Medical College) Ministry of Education Institute of Materia Medica Peking Union Medical College & Chinese Academy of Medical Sciences Beijing 100050 China

Four new chiral 1,2,3,4-tetrahydroisoquinoline-derived G-amino alcohols were synthesized from commercially available LDOPA. These ligands were evaluated in the asymmetric addition of diethylzinc to benzaldehydes and showed different catalytic activities （up to 86% ee）. The solvent played an important role in the enantioselective process. The transition state models were proposed to explain the reversion of the product configuration.

关键词： β-Amino alcohol Tetrahydroisoquinoline Diethylzinc Asymmetric addition

Ni_(2)P/MoS_(2) interfacial structures loading on N-doped carbon matrix for highly efficient hydrogen evolution

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Green Energy & Environment 2022年第4期7卷 829-839页

作者： Yuelong Xu Ran Wang zhan liu Lili Gao Tifeng Jiao Zhenfa liu State Key Laboratory of Metastable Materials Science and Technology Yanshan University438West Hebei StreetQinhuangdao066004China Hebei Key Laboratory of Applied Chemistry School of Environmental and Chemical EngineeringYanshan University438West Hebei StreetQinhuangdao066004China Hebei Engineering Research Center for Water Saving in Industry Shijiazhuang050081China Institute of Energy Resources Hebei Academy of SciencesShijiazhuang050081China

Electrochemical catalysts for the hydrogen evolution reaction(HER) have attracted increasing attentions. Noble metal-free cocatalysts play a vital role in HER applications. Herein, a novel strategy to prepare a Ni_(2)P/MoS_(2) cocatalyst through a simple hydrothermal-phosphorization method was reported, and the prepared cocatalyst was then loaded on an N-doped carbon substrate with excellent conductive performance. The large surface area of the carbon substrate provided many active sites, and the interface between Ni_(2)P and MoS_(2) improved the catalytic performance for the HER. Compared with pure Ni_(2)P catalyst and MoS_(2) catalyst, the prepared Ni_(2)P/MoS_(2) cocatalyst exhibited enhanced catalytic performance. In addition, the results indicate that the prepared cocatalyst has a wide p H range and low onset potential values of 280, 350 and40 m V in acidic, phosphate-buffered saline and alkaline solutions, respectively, and the corresponding Tafel slopes are 75, 121 and 95 mV dec^(-1),respectively. Density functional theory(DFT) was adopted to calculate the hydrogen adsorption free energy(ΔG_(H)^(*)). The results showed that the interface between Ni_(2)P and MoS_(2) reduced ΔG_H^(*), which was beneficial to the adsorption of hydrogen. Present preparation of cocatalysts with unique interfaces provides a new strategy for improving the catalytic performance of HER.

关键词： MoS_(2) Ni_(2)P Hydrogen evolution Electrochemical performance Density functional theory

Synthetic Studies of Et-743, Preparation of A Racemic Amino Alcohol Precursor

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Chinese Chemical Letters 2003年第11期14卷 1127-1129页

作者： zhan Zhu liu Shi Zhi CHEN Institute of Materia Medica Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100050

A mild two-step method was used to cleave the lactam ring of the tricyclic intermediate 1. A key racemic amino alcohol precursor 5 for the construction of Et-743 skeleton was synthesized from 1 through four steps in ... 详细信息

关键词： Et-743 lactam cleavage.

A Case of Abnormal Bishler-Napieralski Cyclization Reaction,Leading to Form Benzyl Oxazole Derivatives

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Chinese Chemical Letters 2001年第3期12卷 195-196页

作者： zhan Zhu liu Shi Zhi CHEN Institute of Materia Medica Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100050

A benzyl oxazole compound 3 was obtained with an excellent yield of 90% when N-acetyl-(2'-methoxy-4',5'-methylenedioxy)-phenylalanine methyl ester 1 was refluxed in POCl1/benzene. However, the anticipated product 3,4-dihydrosioquinoline-3-carboxylic acid methyl ester 2 could not be found. The mechanism was discussed in this article.

关键词： N-Acetyl amino acid oxazole Bishler-Napieralski reaction.

A New Method of Multi-Scale Geologic Modeling and Display

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Journal of Earth Science 2014年第3期25卷 537-543页

作者： Yongliang Bai zhan liu Lanfa liu Roger Mason Binghu Huang School of Geosciences China University of Petroleum Earth Sciences Faculty China University of Geosciences Wuhan

A new method of multi-scale modeling and display of geologic data is introduced to provide information with appropriate detail levels for different types of research. The multi-scale display mode employs a model extending existing 2D methods into 3D space. Geologic models with different scales are organized by segmenting data into orthogonal blocks. A flow diagram illustrates an octree method for upscaling between blocks with different scales. Upscaling data from the smallest unit cells takes into account their average size and the Burgers vector when there are mismatches. A geocellular model of the Chengdao Reservoir of the Shengli Oilfield, China is taken as an illustrative case, showing that the methods proposed can construct a multi-scale geologic model correctly and display data from the multi-scale model effectively in 3D.

关键词： multi-scale geologic model block data organization topological relationship upscale geologic structure multi-scale display.