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Characterization and degradation of β-Sn particles in thermal aged Pb-rich solder joint for low-temperature co-fired ceramic(LTCC)applications

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Rare Metals 2024年第10期43卷 5346-5361页

作者： jin-Hong Liu Zhe Zhu Qiang-Qiang Nie Jun-Fu Liu Peng He Shu-Ye zhang State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China Anhui Key Laboratory of Microsystem East China Research Institute of MicroelectronicsHefei 230088China School of Materials Science and Engineering Hefei University of TechnologyHefei 230009China

High-lead solder joints are still playing an indispensable role in military and space ***,in-depth characterization of high-lead solder joints and the underlying degradation mechanisms remain *** research first performed aging tests on Sn10Pb90 solder joints,the shear strength at room and elevated temperatures gradually reduced,and the resistance ***,a two-layered Ni-Sn intermetallic compound(IMC)structure was identified using transmission electron microscopy(TEM),which could be attributed to the change of Sn content in the ***,the internal annealing twin of a Sn particle was discovered,which could be attributed to creeping induced by thermal expansion coefficient(CTE)difference between Sn and *** analysis of partial and whole annealing twins was conducted through high-resolution TEM(HRTEM).Finally,four degradation mechanisms were *** of the IMC layer would result in increased brittleness and *** particle coarsening,apart from diminishing the ductility and toughness of the solder joint,it would also accelerate the creeping rate by weakening the phase boundary *** voids and cracks induced by phase boundary sliding,wedgeshaped cracking and pore-shaped cracking were discovered and their formation was *** importantly,the consumption of Sn resulted in a depletion of wettable layer,leading to the formation of Pb streams and isolated IMC islands,also known as the spalling and delamination of *** diffusion followed a spiral path,which was mutually influenced by orientation misfit and concentration gradient.A technique to prevent cracking was *** research is expected to provide significant technical references for high-lead solder joints.

关键词： High-lead solder joints Aging TEM characterization Degradation mechanisms Properties

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Chiral pyrrolidine-azole conjugates: Simple and efficient asymmetric organocatalysts for Michael addition to nitrostyrenes

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Chinese Science Bulletin 2010年第17期55卷 1735-1741页

作者： zhang Long XU Hui MI XueLing LUO SanZhong CHENG jin-Pei Department of Chentistry and State Key Laboratory of Elemento-organic Chemistry Nankai University Tianjin 300071 China Beijing National Laboratory for Molecular Sciences (BNLMS) CAS Key Laboratory of Molecular Recognition and Function Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China

Simple pyrrolidine-azole conjugates have been synthesized and found to be efficient catalysts for asymmetric Michael addition to nitrostyrenes. The identified optimal catalysts, pyrrolidine-azoles 2, 8 and 13, could catalyze the asymmetric Michael addition of a range of Michael donors and nitrostyrenes in high yields (up to 99%) and excellent stereoselectivities (up to 99:1 dr and 97% ee).

关键词：不对称Michael加成有机催化剂吡咯烷迈克尔复合物三氮唑手性高效催化剂

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New paleomagnetic results from the Yangzhuang Formation of the Jixian System,North China,and tectonic implications

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Chinese Science Bulletin 2005年第14期50卷 1483-1489页

作者： WU Huaichun zhang Shihong LI Zheng-Xiang LI Haiyan DONG jin State Key Laboratory of Geological Processes and Mineral Resources & Key Laboratory of Lithosphere Tectonics and Lithoprobing Technology of Ministry of Education China University of Geosciences Beijing 100083 China Tectonics Special Research Centre School of Earth and Geographical Sciences The University of Western Australia Crawley WA 6009 Australia

A paleomagnetic study was carried out on the Yangzhuang Formation (~1350 Ma) of the Jixian System in the North China Block (NCB). Detailed stepwise thermal demagnetization isolated two components. The soft compo- nent (component A) was interpreted as a remagnetization in the recent geomagnetic field. The hard component (compo- nent B) with higher unblocking-temperatures was carried by hematite. Its site-mean direction is D/I = 77.6°/-24.3° (κ = 5.4, α95 = 18.3°, N = 15 sites) before, and D/I = 72.2°/11.5° (κ = 24.6, α95 = 7.9°) after tilt correction. It passes a fold test (Mesozoic folding) at 99% confidence level and reversal test at 95% confidence level. The corresponding pole locates at 17.3°N, 214.5°E (dp = 4.1°, dm = 8.0°). A best fit of paleo- magnetic poles from the NCB, Baltica, Siberia and the ap- parent polar wander path for Laurentia suggests a long-lived connection between these paleo-continents between ~1800 and 1350 Ma.

关键词：古磁学中元古代中国岩石

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Wave Extraction and Attenuation Performance of An Edinburgh Duck Wave Energy Converter

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China Ocean Engineering 2021年第6期35卷 905-913页

作者： ZHOU Bin-zhen LI Jia-hui zhang Heng-ming CHEN Li-fen WANG Lei jin Peng School of Civil Engineering and Transportation South China University of TechnologyGuangzhou 510641China College of Shipbuilding Engineering Harbin Engineering UniversityHarbin 150001China State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China

Edinburgh Duck wave energy converter(ED WEC)has excellent energy extraction performance and shows a great potential to integrate with other marine *** paper aims to investigate its wave energy extraction performance as a WEC and wave attenuation performance as a protection method for shoreline or marine *** wave and ED WEC interactions in regular waves are modeled using the Star-CCM+software and verified by comparisons with published experimental *** motion response,energy conversion efficiency,and transmission coefficient of the ED WEC with different attack angles,rotation center,and incident wave heights are *** indicate that the ED WEC with an attack angle of 42°and a rotation center of 0.55 m below the mean water line can achieve both good wave energy extraction and wave attenuation *** wave energy extraction and wave attenuation performance of the ED WEC decrease significantly with the increase of wave nonlinearity characterized by the wave *** paper can guide the practical application of the ED WEC at the early stage of design.

关键词： Edinburgh Duck wave energy converter wave energy extraction wave attenuation wave nonlinearity

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Computational prediction of microRNA genes in silkworm genome

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2006年第10期7卷 806-816页

作者： TONG Chuan-zhou jin Yong-feng zhang Yao-zhou Institute of Biochemistry School of Life Science Zhejiang University Hangzhou 310029 China Institute of Biochemistry School of Life Sciences Zhejiang Science and Technology University Hangzhou 310018 China

MicroRNAs （miRNAs） constitute a novel, extensive class of small RNAs （-21 nucleotides）, and play important gene-regulation roles during growth and development in various organisms. Here we conducted a homology search to identify homologs of previously validated miRNAs from silkworm genome. We identified 24 potential miRNA genes, and gave each of them a name according to the common criteria. Interestingly, we found that a great number of newly identified miRNAs were conserved in silkworm and Drosophila, and family alignment revealed that miRNA families might possess single nucleotide polymorphisms, miRNA gene clusters and possible functions of complement miRNA pairs are discussed.

关键词： miRNA Silkworm Computational prediction

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Fabrication of Intracranial Vascular Nitinol Alloy Stents with Improved Mechanical Property and Endothelialization Function

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Acta Metallurgica Sinica(English Letters) 2022年第12期35卷 2069-2081页

作者： Yangyang Yan Na Li Feng Guo Anhua Wu Wei jin Rui Yang Yun Bai Xing zhang Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China College of Life Science and Engineering Shenyang UniversityShenyang 110044China Department of Neurosurgery The First Affi liated Hospital of China Medical UniversityShenyang 110001China

Intracranial vascular stenting has been widely used for ischemic ***,there are complication risks with stent implantation,such as poor wall apposition,stent migration,thromboembolism and stent restenosis,due to the mismatched radial force and conformability of the stents."Therefore,a novel intracranial vascular nitinol stent was fabricated in order to improve mechanical property and endothelialization *** bending moment of the stents was calculated to be 0.346 N mm,which shows improved *** radial force of the stents evaluated by the flat plate test was0.0112 N/mm,within the range of the commercially available stent force(0.0065-0.0116 N/mm).Furthermore,the TyrIle-Gly-Ser-Arg(YIGSR)peptide derived from laminin was grafted onto the stent surfaces to promote endothelialization on vascular stents evaluated by the proliferation,adhesion and migration of human umbilical vein endothelial cells in *** nitinol stents with improved mechanical property and endothelialization function are expected to reduce the recurrence risk of ischemic stroke after implantation.

关键词： Nitinol stents Conformability Radial force Endothelialization Intracranial stenosis treatment

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Interaction of copper with fatty acids in Soxhlet extraction and its influence

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Chinese Journal Of Geochemistry 2008年第2期27卷 157-160页

作者： jin Ming XIA Yanqing LEI Tianzhu QIU Junli zhang Rui Key Laboratory of Gas Geochemistry Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou 730000 China Graduate School Chinese Academy of Sciences Beijing 100039 China

Treatment with metallic copper for the removal of elemental sulfur from bitumen extracted from sedimentary rocks or petroleum is the most widely used method. Little attention has been paid, however, to its disadvantages. It was observed that copper can interact with some polar organic substances during conventional sulfur removal, which can strongly influence the quantitative and qualitative determination of bitumen, as has been confirmed by interaction of long-chain fatty acids with copper. The copper soap generated was analyzed by element analysis, inductively coupled plasma optical emission spectrometry (ICP-OES), thermal analysis (TG-DSC) and Fourier Transform Infrared spectroscopy (FTIR). Mechanism of the interaction was investigated and elucidated. Our experimental results would necessitate improvement of the present method for sulfur removal and/or a search for a new one.

关键词：硫磺铜处理脂肪酸沥青

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Electrochemical Cycled Structure of MnV_2O_6 Nanoribbons Synthesized via Hydrothermal Route

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Chemical Research in Chinese Universities 2011年第3期27卷 528-530页

作者： HU Fang zhang Chun-hua zhang Song MING Xing CHEN Gang WEI Ving-jin WANG Chun-zhong School of Materials Science and Engineering Shenyang University of Technology Shenyang 110870 P. R. China＂ College of Physics and State Key Laboratory of Superhard Materials Jilin University Changchun 130012 P. R. Chin~ Sollege of Physical Science and Technology Huanggang Normal University Huanggang 438000 P. R. China

1 Introduction Low-dimensional nanostructures, such as nanorods, nanowires, and nanotubes, have received much attention for their superior optical, electrical, catalytic and magnetic properties. Owing to their low dimensionality and quantum continement effect, low-dimensional nanoscale materials can be exploited as fundamental building blocks for nanoscience and nanodevices^[1-3]. In recent years, efforts have been devoted to develop new approaches to synthesize one-dimensional（lD） nanostructrued vanadium oxides or vanadates materials, such as V205, NaV2Os, and CuV206, which have been widely investigated in catalytic or electrochemical fields due to their outstanding structural flexibility^[4-6].

关键词： MnV2O6 Hydrothermal route Electrochemical property Cycled structure

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Stable mechanical fixation in a bionic osteochondral scaffold considering bone growth

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Rare Metals 2022年第8期41卷 2711-2718页

作者： Jian Zhou Hao Huang Li-jing Wang Maryam Tamaddon chao-Zong Liu Zi-Yu Liu Teng-Bo Yu Ying-Ze zhang Department of Orthopaedic Surgery Qingdao Municipal HospitalQingdao UniversityQingdao266071China Department of Sports Medicine Affiliated Hospital of Qingdao UniversityQingdao266000China Division of Surgery&Interventional Science University College LondonRoyal National Orthopaedic HospitalLondonHA74LPUK School of Aeronautic Science and Engineering Beihang UniversityBeijing100191China School of Engineering Medicine Beihang UniversityBeijing100191China

In the field of tissue engineering,there is significant subsidence of the porous design scaffold several months after *** avoid stress shielding and stimulate bone and cartilage ingrowth,high scaffold porosity is needed to diminish the mechanical properties of the *** closer the mechanical properties of the scaffold are to those of surrounding tissues,the better biological properties it will ***,adequate mechanical stability is needed as the scaffold needs to be well fixed in the target area and it will endure load after *** the mechanical fixation of the scaffold at the initial stage and the long-term performance of a scaffold for in vivo study is hard,as no facility can be put into the target area for the friction *** study investigated the mechanical stability of the biomimetic scaffold at the initial stage of implantation by finite element analysis(FEA).According to in vivo study,scaffold could not maintain its original position and would sink 1-2 mm in the target *** simulation results suggested that mechanical loading is not the main reason for scaffold subsidence.

关键词： Osteochondral scaffold Mechanical fixation Scaffold subsidence Bone ingrowth

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Promotion mechanism of self-transmissible degradative plasmid transfer in maize rhizosphere and its application in naphthalene degradation in soil

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Journal of Environmental Sciences 2022年第5期34卷 240-252页

作者： Qiuyan Jiang Wenwei Lu Lei zhang Yeqing jin Yujing Wang Jun Chen Ziyi Ye Ming Xiao Development Center of Plant Germplasm College of Life SciencesShanghai Normal UniversityShanghai 200234China Key Laboratory of Urban Agriculture Ministry of AgricultureShanghai 200240China Department of Food Science Shanghai Business SchoolShanghai 200235China Shanghai Landscape Architecture Construction Co. Ltd.Shanghai 200235China

Rhizospheres can promote self-transmissible plasmid transfer,however,the corresponding mechanism has not received much ***-microbe remediation is an effective way to promote pollutant biodegradation;however,some pollutants,such as naphthalene,are harmful to plants and result in inefficient plant-microbe *** this study,trans-fer of a TOL-like plasmid,a self-transmissible plasmid loaded with genetic determinants for pollutant degradation,among different bacteria was examined in bulk and rhizosphere soils as well as addition of maize root exudate and its artificial root exudate(ARE).The results showed that the numbers of transconjugants and recipients as well as bacterial metabolic activities,such as xylE mRNA expression levels and catechol 2,3-dioxygenase(C23O)activ-ities of bacteria,remained high in rhizosphere soils,when compared with bulk *** number of transconjugants and bacterial metabolic activities increased with the increasing exudate and ARE concentrations,whereas the populations of donor and recipient bacteria were substantially unaltered at all *** the experiments consistently showed that a certain number of bacteria is required for self-transmissible plasmid transfer,and that the increased plasmid transfer might predominantly be owing to bacterial metabolic activ-ity stimulated by root exudates and ***,ARE addition increased naphthalene degradation by transconjugants in both culture medium and ***,the combined action of a wide variety of components in ARE might contribute to the increased plasmid transfer and naphthalene *** findings suggest that ARE could be an effectively al-ternative for plant-microbe remediation of pollutants in environments where plants cannot survive.

关键词： Degradative plasmid transfer Naphthalene degradation Rhizosphere Root exudates

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