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Hot deformation behavior of a near alpha titanium alloy with/without thermal hydrogen processing

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Acta Metallurgica Sinica(English Letters) 2010年第2期23卷 106-112页

作者： Qing WANG Dongli SUN xiuli han Weigong WANG School of Materials Science and Engineering Harbin Institute o) Technology Harbin 150001 China

The true stress-true strain curves of Ti-6Al-2Zr-IMO-IV alloy with hydrogen were obtained by hot compression test. The microstructures of the alloy before and after thermo-compression were observed. The apparent activation energies of deformation were calculated for the alloy with and without hydrogen. The behavior and mechanism of deformation for hydrogenated Ti-6A1-2Zr-IMO-IV alloy at high temperature were analyzed. The relationship between hydrogenation time and hydrogen content at 800 ℃ can be expressed as the equation： CH（t）=1.2-1.2exp（-t/120）. The true stress-true strain curves of hot compression for Ti-6Al-2Zr-IMO-IV alloy with hydrogen first move down and then move up as hydrogen content increases. Appropriate hydrogen content can reduce the peak of flow stress to minimal value. The apparent activation energies of deformation of the alloy with 0.47% hydrogen content and without hydrogen were calculated as 140 kJ·mol^-1 and 390 kJ-mol^-1, respectively, at 800 ℃ and at strain rate 8.3×10^4 s^-1. The apparent activation energy of deformation increases when the strain rate enhances from 8.3×10^-4 s^-1 to 8.3×10^-2 s^-1.

关键词： Titanium alloy Thermal hydrogen processing Compression at high temperature Hot deformation behavior Apparent activa- tion energy of deformation Microstructure

Friction and Wear Properties of TiAl and Ti_2AlN/TiAl Composites at High Temperature

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Journal of Wuhan University of Technology(Materials Science) 2013年第5期28卷 1023-1028页

作者：孙东立 SUN Tao WANG Qing han xiuli GUO Linlin School of Materials Science and Engineering Harbin Institute of Technology

The high-temperature friction and wear properties of TiAl alloys and Ti2AlN/TiAl composites （TTC） in contact with nickel-based superalloy were studied. The results showed that, at 800 and 1 000 ℃, the coefficient of the friction （COF） decreased with the increase of sliding velocity and the wear loss of the TTC decreased with the increase of volume fraction of Ti2AlN. The wear mechanisms of the pairs are adhesive wear and the wear debris mainly comes from the contacting nickel-based superalloy. The intergranular fracture and the cracking of the phase boundary in the lamellar structure are the wear mode of TiAl alloy. The wear mode of TTC is phase boundary fracture and adhesive spalling. The abrasive resistance of TTC is slightly higher than that of TiAl alloy.

关键词： TiA1 alloy Ti2A1N/TiA1 composites friction and wear at high-temperaturer

Two New Inorganic-organic Hybrid Compounds Constructed from Different Polymolybdates and Transition Metal-amine Subunits

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Chemical Research in Chinese Universities 2015年第3期31卷 337-341页

作者： WANG xiuli LIU Danna han Na LIN Hongyan LUAN Jian TIAN Aixiang Liaoning Province Silicon Materials Engineering Technology Research Centre Department of ChemistryBohai University Jinzhou 121000 P.R.China

Two new polyoxometalate（POM）-based hybrid compounds, [Cu（en）][H4Mo4O16]0.5（1）（en=ethylenediamine） and [Ag（3-CsH6N2）2][H2PMo12O40]（2）（3-C5H6N2=3-aminopyridine）, containing different transition metal- amine subunits were hydrothermally synthesized and characterized by elemental analyses, infrared spectroscopy and single-crystal X-ray diffraction. For compound 1, each [H4Mo4O16]4-（M04O16） cluster was linked to four neighboring Mo4O16 clusters through four [Cu（en）]2＋ subunits to yield a （2,4）-connected 2D layer, which was further extended to a 3D supramolecular network via hydrogen bonding interactions. For compound 2, the adjacent [H2PMo12O40]- clusters were bridged by [Ag（3-C5H6N2）2]＋ subunits to generate a 1D chain. The electrochemical behaviors and the photoca- talytic activities of compounds 1 and 2 were studied in detail.

关键词： Polyoxometalate Metal-amine unit Crystal structure Electrochemical property Photocatalysis

Fabrication of in situ Ti_2AlN/TiAl Composites by Reaction Hot Pressing and Their Properties

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Journal of Wuhan University of Technology(Materials Science) 2014年第1期29卷 126-130页

作者：孙东立 SUN Tao WANG Qing han xiuli GUO Qiang WU Gaohui School of Materials Science and Engineering Harbin Institute of Technology

Ti2AIN/TiAI composites with different volume fractions of reinforcement were successfully fabricated by hot-pressing sintering method （reaction hot pressing） using Ti, Al and TiN powders as starting materials. The synthesis process includes four stages： first, the reactions between Al and Ti powers and between Al and TiN powders respectively occur and result in TiAl3 phase; secondly, AI powders in the sample are exhausted; the remaining Ti cores react with TiAl3 layer to form Ti-Al intermetallics; moreover, a few Ti2AlN particles precipitate from the TiAl3 phase; thirdly, Ti-Al intermetallics react with the remaining Ti cores to form Ti3Al and TiAl phases. TiAl phase and original TiN powers are in direct contact each other; finally, the residual TiN powers react with TiAl phase and result in a plenty of TizAIN phase. Compared with TiAl matrix, the hardness, elastic modulus and high-temperature compressive strength of Ti2AlN/TiAl composite are improved obviously and they are all enhanced with increasing the volume fraction of Ti2AlN phase.

关键词： composites titanium aluminides mechanical properties sintering electron microscopy transmission

Research on Data Extraction and Analysis of Software Defect in IoT Communication Software

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Computers, Materials & Continua 2020年第11期65卷 1837-1854页

作者： Wenbin Bi Fang Yu Ning Cao Wei Huo Guangsheng Cao xiuli han Lili Sun Russell Higgs School of Computer and Software Dalian Neusoft University of InformationDalian116023China School of Information Engineering Qingdao Bin Hai UniversityQingdao266555China School of Internet of Things and Software Technology Wuxi Vocational College of Science and TechnologyWuxi214028China Public Teaching Department Neuedu Software Talent Training SchoolQingdao266000China Public Teaching Department Qingdao Technical CollegeQingdao266555China School of Information Engineering Sanming UniversitySanming365004China School of Mathematics and Statistics University College DublinDublinIreland

Software defect feature selection has problems of feature space dimensionality reduction and large search *** research proposes a defect prediction feature selection framework based on improved shuffled frog leaping algorithm(ISFLA).Using the two-level structure of the framework and the improved hybrid leapfrog algorithm's own advantages,the feature values are sorted,and some features with high correlation are selected to avoid other heuristic algorithms in the defect prediction that are easy to produce local The case where the convergence rate of the optimal or parameter optimization process is relatively *** framework improves generalization of predictions of unknown data samples and enhances the ability to search for features related to learning *** the same time,this framework further reduces the dimension of the feature *** the contrast simulation experiment with other common defect prediction methods,we used the actual test data set to verify the framework for multiple iterations on Internet of Things(IoT)system *** experimental results show that the software defect prediction feature selection framework based on ISFLA is very effective in defect prediction of IoT communication *** framework can save the testing time of IoT communication software,effectively improve the performance of software defect prediction,and ensure the software quality.

关键词： Improved shuffled frog leaping algorithm defect prediction feature selection framework Internet of Things

Dynamic changes of phosphatidylinositol and phosphatidylinositol 4-phosphate levels modulate H^(+)-ATPase and Na^(+)/H^(+) antiporter activities to maintain ion homeostasis in Arabidopsis under salt stress

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Molecular Plant 2021年第12期14卷 2000-2014页

作者： Yongqing Yang xiuli han Liang Ma Yujiao Wu Xiao Liu Haiqi Fu Guoyong Liu Xiaoguang Lei Yan Guo State Key Laboratory of Plant Physiology and Biochemistry College of Biological SciencesChina Agricultural UniversityBeijing 100193China College of Life Sciences Shandong University of TechnologyZibo 255049China Beijing National Laboratory for Molecular Sciences Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of EducationDepartment of Chemical BiologyCollege of Chemistry and Molecular EngineeringSynthetic and Functional Biomolecules Centerand Peking-Tsinghua Center for Life SciencesPeking UniversityBeijing 100871China

Plant metabolites are dynamically modified and distributed in response to environmental ***-ever,it is poorly understood how metabolic change functions in plant stress *** ion ho-meostasis under salt stress requires coordinated activation of two types of central regulators:plasma membrane(PM)H^(+)-ATPase and Na^(+)/H^(+) *** this study,we used a bioassay-guided isolation approach to identify endogenous small molecules that affect PM H^(+)-ATPase and Na^(+)/H^(+) antiporter activities and identified phosphatidylinositol(PI),which inhibits PM H^(+)-ATPase activity under non-stress conditions in Arabidopsis by directly binding to the C terminus of the PM H^(+)-ATPase *** salt stress,the phosphatidylinositol 4-phosphate-to-phosphatidylinositol(PI4P-to-PI)ratio increased,and PI4P bound and activated the PM Na^(+)/H^(+) *** prefers binding to the inactive form of PM H^(+)-ATPase,while PI4P tends to bind to the active form of the Na^(+)/H^(+) *** with this,pis1 mutants,with reduced levels of PI,displayed increased PM H^(+)-ATPase activity and salt stress toler-ance,while the pi4kβ1 mutant,with reduced levels of PI4P,displayed reduced PM Na^(+)/H^(+) antiporter activity and salt stress ***,our results reveal that the dynamic change between PI and PI4P in response to salt stress in Arabidopsis is crucial for maintaining ion homeostasis to protect plants from un-favorable environmental conditions.

关键词： Arabidopsis thaliana endogenous small molecules H^(+)-ATPase Na^(+)/H^(+)antiporter salt stress

Semantics Analytics of Origin-Destination Flows from Crowd Sensed Big Data

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Computers, Materials & Continua 2019年第7期61卷 227-241页

作者： Ning Cao Shengfang Li Keyong Shen Sheng Bin Gengxin Sun Dongjie Zhu xiuli han Guangsheng Cao Abraham Campbell College of Computer Information and Engineering Nanchang Institute of TechnologyNanchangChina College of Information Engineering Sanming UniversitySanmingChina School of Data Science and Software Engineering Qingdao UniversityQingdaoChina School of Computer Science and Technology Harbin Institute of TechnologyWeihaiChina Public Teaching Department Qingdao Technical CollegeQingdaoChina School of Computer Science University College DublinDublinIreland

Monitoring,understanding and predicting Origin-destination(OD)flows in a city is an important problem for city planning and human ***-GPS traces,acted as one kind of typical crowd sensed data,it can be used to mine the semantics of OD *** this paper,we firstly construct and analyze a complex network of OD flows based on large-scale GPS taxi traces of a city in *** spatiotemporal analysis for the OD flows complex network showed that there were distinctive patterns in OD *** based on a novel complex network model,a semantics mining method of OD flows is proposed through compounding Points of Interests(POI)network and public transport network to the OD flows *** propose method would offer a novel way to predict the location characteristic and future traffic conditions accurately.

关键词： Origin-destination(OD)flows semantics analytics complex network big data analysis

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比例原则进入WTO法的必要性分析

中共福建省委党校学报 2005年第8期 14-17页

作者：韩秀丽厦门大学福建厦门361005

比例原则是国内行政法与宪法及国际法中的重要原则,具有丰富的内涵,发挥着重要作用。比例原则要求综合各种情况,平衡各种利益,联系WTO的实际需要及WTO成员方的建议,比例原则有必要进入WTO法。

关键词：比例原则 WTO法必要性

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非洲国家豁免立场的转向及中国因应

西亚非洲 2024年第5期 3-21,151,152页

作者：韩秀丽张启扉厦门大学法学院非洲法与国际法研究中心厦门大学法学院

非洲国家独立后,基于维护国家主权、谋求平等与公平之利益诉求,受到原宗主国法律体系的一定影响,以及在全球限制豁免主流趋势的席卷之下,大多由绝对豁免转向限制豁免立场。非洲国家限制豁免实践呈现不同形式,个别国家颁布了限制外国国... 详细信息

非洲国家独立后,基于维护国家主权、谋求平等与公平之利益诉求,受到原宗主国法律体系的一定影响,以及在全球限制豁免主流趋势的席卷之下,大多由绝对豁免转向限制豁免立场。非洲国家限制豁免实践呈现不同形式,个别国家颁布了限制外国国家豁免的国内立法,部分国家采取限制外国国家豁免的司法实践,而更多国家则参与了包含限制豁免内容的国际条约。作为对外关系的重要方面,外国国家豁免会对国家间关系产生重要影响。对于中非合作而言,在双方共建高质量“一带一路”背景下,随着中非民商事交往日益紧密,非洲国家的限制豁免转向将对中非合作产生重要影响,尤其是将给中国主权性实体带来一定风险和挑战。鉴此,中方需关注非洲国家的国家豁免立场与实践新动向,基于维护中非友好合作的大局,在事前与事后两个维度加以应对。具体而言,一方面,中方应深入研究非洲国家豁免问题,积极与非洲国家就国家豁免开展国际立法、司法对话合作;另一方面,中国国有企业在非洲法院涉诉时,依据不同情况选择是否提出国家豁免抗辩,而中国政府及其分支机构在非洲法院涉诉时,应重视并充分利用外交意见机制,为大变局时代推进中非合作关系作出贡献。

关键词：国家豁免非洲绝对豁免限制豁免中非合作

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