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One-pot Synthesis of 1,5-Diaza-2,6-cyclooctadiene-3,7-dicarboxylates Through a Multiple-component Reaction

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Chemical Research in Chinese Universities 2014年第3期30卷 387-389页

作者： LI yufeng wang Xinglong LI Wei WU Zhengguang SHI Jie MA Hongfei College of Science Nanjing Tech University Nanjing 211816 P. R. China

Methyl propiolate, formaldehyde, and various acyclic amines were assembled in one-pot into a series of 1,5-diaza-2,6-cyclooctadiene-3,7-dicarboxylates in moderate to good yields. This multiple-component reaction benef... 详细信息

关键词： Multiple-component reaction Methyl propiolate 1,5-Diaza-2,6-cyclooctadiene-3,7-dicarboxylate

New Developed Welding Electrode for Improving the Fatigue Strength of Welded Joints

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Journal of Materials Science & Technology 2002年第6期18卷 527-531页

作者： Wenxian wang, Lixing HUO, yufeng ZHANG, Dongpo wang and Hongyang JINGCollege of Material Science and Engineering, Tianjin University, Tianjin 300072, China Coll. of Mat. Sci. and Eng. Tianjin Univ. Tianjin 300072 China

A new welding electrode, low transformation temperature electrode (LTTE), was introduced in this paper. It was described in design principle, mechanics, chemical compositions of their deposited metal and manufacturing methods. It was proved that the best transformation starting temperature from austenite to martensite of the deposited metal of LTTE was at about 191℃ and it was obtained by adding alloying elements such as Cr, Ni, Mn and Mo. The microstructure of the weld metal of the LTTE was low carbon martensite and residual austenite. The compressive residual stress was induced around the weld of the LTTE and the -145 MPa in compression could be obtained in middle of weld metal. The fatigue tests showed that the fatigue strength of the longitudinal welded joints welded with the LTTE at 2×106 cycles was improved by 59% compared with that of the same type of welded joints welded with conventional E5015 and the fatigue life was increased by 47 times at 162 MPa. It is a very valuable method to improve the fatigue performance of welded joints.

关键词： Low transformation temperature electrode Compressive residual stress Fatigue strength Welded joints

Experimental Investigation on Microstructure and Segregation of Ultrahigh Strength Al-Zn-Mg-Cu-Zr-Sc-Ni Alloy during Homogenization

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稀有金属材料与工程 2009年第A3期38卷 83-87页

作者： Li Zhenliang Xie Jianxin Chen Wei Zhai Jing Ren Huiping wang yufeng University of Science and Technology Beijing Beijing 100083 China Ningbo Branch of China Academy of Ordnance Science Ningbo 315103 China Inner Mongolia University of Science and Technology Baotou 014010 China

Ultrahigh strength Al-12Zn-2.4Mg-1.1Cu-0.20Zr-0.30Sc-0.30Ni alloy billets were fabricated by spray deposition method(the Osprey process). The effect of homogenization treatment on the microstructures and tensile properties were investigated by OM, SEM and EDS. The results show that adding small amount of Sc and Zr can greatly refine the grain size of the billet, with the average grain size of 10 μm. Grain-boundary becomes coarser firstly and then thinner under different homogenizing condition and grain coarsening were observed. The solute elements content of Zn inside grains has a peak at 490 ℃ /2 h, and Cu element, which was solved into matrix, can enhance the matrix hardness obviously during homogenization. The suitable homogenizing treatment is 460～490 °C/2 h for the hot extrusion of the studied alloy; after the optimized solid solution and T6 aging, the highest ultimate tensile strength (UTS) is 858 MPa with a ductility of 4.8%.

关键词：喷射沉积方法晶粒合金热挤压

Artificial intelligence optimization and controllable slow-release iron sulfide realizes efficient separation of copper and arsenic in strongly acidic wastewater

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Journal of Environmental Sciences 2024年第5期139卷 293-307页

作者： Xingfei Zhang Chenglong Lu Jia Tian Liqiang Zeng yufeng wang Wei Sun Haisheng Han Jianhua Kang School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China Centre for Mined Land Rehabilitation Sustainable Minerals InstituteThe University of QueenslandBrisbane 4072Australia

Iron sulfide(FeS)is a promising material for separating copper and arsenic from strongly acidic wastewater due to its S^(2-)slow-release ***,uncertainties arise because of the constant changes in wastewater composition,affecting the selection of operating parameters and FeS *** this study,the aging method was first used to prepare various controllable FeS nanoparticles to weaken the arsenic removal ability without affecting the copper *** experiments were conducted,and the results identified the Cu/As ratio,H_(2)SO_(4) concentration,and FeS dosage as the three main factors influencing the separation *** backpropagation artificial neural network(BP-ANN)model was established to determine the relationship between the influencing factors and the separation *** correlation coefficient(R)of overall model was 0.9923 after optimizing using genetic algorithm(GA).The BP-GA model was also solved using GA under specific constraints,predicting the best solution for the separation process in *** predicted results show that the high temperature and long aging time of FeS were necessary to gain high separation efficiency,and the maximum separation factor can reached 1,*** study provides a suitable sulfurizing material and a set of methods and models with robust flexibility that can successfully predict the separation efficiency of copper and arsenic from highly acidic environments.

关键词： FeS nanoparticles Aging Sulfide precipitation Orthogonal experiment Artificial neural network Prediction

Collaborative manufacturing technologies of structure shape and surface integrity for complex thin-walled components of aero-engine:Status,challenge and tendency

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Chinese Journal of Aeronautics 2023年第7期36卷 1-24页

作者： Biao ZHAO Wenfeng DING Zhongde SHAN Jun wang Changfeng YAO Zhengcai ZHAO Jia LIU Shihong XIAO Yue DING Xiaowei TANG Xingchao wang yufeng wang Xin wang College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China School of Mechanical Engineering Northwestern Polytechnical UniversityXi’an 710072China AVIC Manufacturing Technology Institute Beijing 100024China School of Mechanical Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China AECC Shenyang Liming Aero-engine Co. LTD.Shenyang 110000China

Presently,the service performance of new-generation high-tech equipment is directly affected by the manufacturing quality of complex thin-walled components.A high-efficiency and quality manufacturing of these complex thin-walled components creates a bottleneck that needs to be solved urgently in machinery *** address this problem,the collaborative manufacturing of structure shape and surface integrity has emerged as a new process that can shorten processing cycles,improve machining qualities,and reduce *** paper summarises the research status on the material removal mechanism,precision control of structure shape,machined surface integrity control and intelligent process control technology of complex thin-walled *** solutions and technical approaches are then put forward to solve the critical problems in the high-performance manufacturing of complex thin-wall *** development status,challenge and tendency of collaborative manufacturing technologies in the high-efficiency and quality manufacturing of complex thin-wall components is also discussed.

关键词： Collaborative manufacturing of shape and performance Complex thin-walled component Intelligent process control Material removal mechanism Surface integrity

TCD5 Enhances the Photosynthesis Capacity,Increases the Panicle Number and the Yield in Rice

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Phyton-International Journal of Experimental Botany 2023年第9期92卷 2649-2663页

作者： Jing Yang yufeng wang Zhanghua Hu Xiaoping Chen Yanjun Dong Sheng Teng Zhejiang Provincial Key Laboratory of Biometrology and Inspection&Quarantine College of Life SciencesChina Jiliang UniversityHangzhou310018China CAS Center for Excellence in Molecular Plant Sciences Chinese Academy of SciencesShanghai200032China Institute of Virology and Biotechnology Zhejiang Academy of Agricultural SciencesHangzhou310021China Agrotechnical Extension Station in Tiantai County Taizhou317200China College of Life Sciences Shanghai Normal UniversityShanghai200234China

Improvement of photosynthetic efficiency is a major approach to increase crop yield ***,we cloned a gene encoding the chloroplast-located putative monooxygenase TCD5,which is essential in plastid development under low temperature in rice(Oryza sativa L.).In this study,the effects of TCD5 on the photosynthesis and the yields were investigated in *** sets of genetic materials with three levels of TCD5 expression,including tcd5 mutant or TCD5 RNAi transgenic lines and TCD5 over-expression transgenic lines in Jiahua1 and Nipponbare backgrounds,were used in the field trails of multi-locations and ***5 positively affected the panicle number and the yield at *** with the wild-types,the panicle numbers were 12.4%-14.6%less in tcd5 mutant and 8.3%-38.6%less in TCD5 RNAi lines,but 26.2%-61.8%more in TCD5 over-expression *** grain yields per plant were 9.1%-18.4%less in tcd5 mutant and 14.3%-56.7%less in TCD5 RNAi lines,but 6.9%-56.5%more in TCD5 over-expression *** measurements of net photosynthetic rate indicated that mutation or knock down of TCD5 decreased the net photosynthetic rate by 10.4%and 15.6%,respectively,while increasing it by 8.9%and 8.7%in the TCD5 over-expression lines in Jiahua1 and Nipponbare backgrounds,***,the measurements of chlorophyll fluorescence parameters showed that the electron transport rate and quantum yield decreased in tcd5 mutant or TCD5 RNAi lines but increased in TCD5 overexpression lines,both in Jiahua1 and Nipponbare ***-MS screening revealed that TCD5 interacts with 29 chloroplast proteins involved in chlorophyll synthesis,photo-reactions of the photosynthesis,carbon assimilation and metabolism,energy metabolism,redox balance,protein synthesis and *** TCD5 interacted proteins,D1 and FBA were effective targets for improving *** results suggest a potentially new strategy for increasing rice yield by enhancing photosynthe

关键词： TCD5 photosynthesis panicle number yield

Nano-calcium silicate mineralized fish scale scaffolds for enhancing tendon-bone healing

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Bioactive Materials 2023年第2期20卷 29-40页

作者： Fei Han Tian Li Mengmeng Li Bingjun Zhang yufeng wang Yufang Zhu Chengtie Wu State Key Laboratory of High-Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai200050PR China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing100049PR China Department of Orthopaedic Surgery Nanjing First HospitalNanjing Medical UniversityNanjing210006PR China

Tendon-bone healing is essential for an effective rotator cuff tendon repair surgery,however,this remains a significant challenge due to the lack of biomaterials with high strength and *** by the high-performance exoskeleton of natural organisms,we set out to apply natural fish scale(FS)modified by calcium silicate nanoparticles(CS NPs)as a new biomaterial(CS-FS)to overcome the *** from its“Bouligand”microstructure,such FS-based scaffold maintained excellent tensile strength(125.05 MPa)and toughness(14.16 MJ/m^(3)),which are 1.93 and 2.72 times that of natural tendon respectively,allowing it to well meet the requirements for rotator cuff tendon ***,CS-FS showed diverse bioactivities by stimulating the differentiation and phenotypic maintenance of multiple types of cells participated into the composition of tendon-bone junction,(*** marrow mesenchymal stem cells(BMSCs),chondrocyte,and tendon stem/progenitor cells(TSPCs)).In both rat and rabbit rotator cuff tear(RCT)models,CS-FS played a key role in the tendon-bone interface regeneration and biomechanical function,which may be achieved by activating BMP-2/Smad/Runx2 pathway in ***,natural fish scale-based biomaterials are the promising candidate for clinical tendon repair due to their outstanding strength and bioactivity.

关键词： Fish scales Tendon repair High strength Bioactivities Tendon-bone healing enhancement

Preparation of uranium targets by electro-deposition method

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Nuclear Science and Techniques 2010年第3期21卷 161-164页

作者： HE Jiaheng CHEN Qiping ZHONG Wenbin LI Xingliang wang Jing DANG yufeng LIU Guopin Institute of Nuclear Physics and Chemistry . China Academy of Engineering Physics Mianyang 621900 China

In this paper,uranium targets are prepared by *** uranium dioxide films are electrodeposited into stainless steel plates using uranyl nitrate in ammonium oxalate *** results show that the deposition efficiency of the uranium depends on many parameters,such as pH value,supporting electrolyte, current density,and cell *** uranium films were characterized by infrared spectrum,scanning electron microscope,and X-ray *** uranium films,with a yield of 98%,are in the thickness of about 6 mg·cm^(-2).

关键词：电沉积法铀靶制备扫描电子显微镜支持电解质不锈钢板沉积效率单元设计

Optimum Design of Lightweight Silicon Carbide Mirror Assembly

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Journal of Wuhan University of Technology(Materials Science) 2008年第2期23卷 259-262页

作者： HAN Yuanyuan ZHANG Yumin HAN Jiecai ZHANG Jianhan YAO wang ZHOU yufeng Center for Composite Materials Harbin Institute of Technology Harbin 150080 China

According to the design requirement and on the basis of the principle that the thermal expansion coefficient of the support structure should match with that of the mirror, a lightweight silicon carbide primary mirror assembly was designed. Finite element analysis combined with the parameter-optimized method was used during the design. Lightweight cell and rigid rib structure were used for the mirror assembly. The static, dynamic and thermal properties of the primary mirror assembly were analyzed. It is shown that after optimization, the lightweight ratio of the silicon carbide mirror is 52.5%, and the rigidity of the silicon carbide structure is high enough to support the required mirror. When temperature changes, the deformation of the mirror surface is in proportion to the temperature difference.

关键词： silicon carbide mirror assembly optimum design finite element