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Progress in Natural Science:Materials International 2015年第5期25卷 365-369页

作者： Zhidong Han Xue liu shaofan Zhao Yang shao Jinfeng li Kefu Yao School of Materials Science and Engineering Tsinghua University

Owning to their excellent thermal stability and high strength at elevated temperature,high entropy alloys(HEAs) possess great potential for the application in aviation and aerospace *** present work,two novel Nb-Ni-Ti-Co-Zr and Nb-Ni-Ti-Co-Zr-Hf HEAs were prepared by arc melting and copper mold suction-casting *** microstructure,phase stability,mechanical properties at room temperature and elevated temperature of the two HEAs were *** of the HEAs possess high yield stress at room temperature,especially for the Nb-Ni-Ti-Co-Zr(with 2331 Mpa).In addition,the Nb-Ni-Ti-Co-Zr HEA exhibited high yield stress of 564 Mpa at elevated temperature of 800 ℃ and large compressive plastic strain(more than 50%at 800 ℃).Nb-Ni-Ti-Co-Zr-Hf alloy showed new phase precipitation at 800 ℃,whereas the structure of Nb-Ni-Ti-Co-Zr was more stable,which is one of the reason why it possesses high strength at room temperature and elevated *** high temperature properties of the Nb-Ni-Ti-Co-Zr HEA make it promising for high temperature application.

关键词： High entropy alloy Mechanical property Microstructure,Stability

Rules of variation in hydrogen during reignition of underground fire zones of spontaneous coal combustion

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Mining Science and Technology 2010年第4期20卷 499-503页

作者： ZHOU Fubao li Jinhai liU Yusheng shao He School of Safety Engineering China University of Mining ＆ Technology Xuzhou 221008 ChinaState Key Laboratory of Coal Resources and Safe Mining China University of Mining ＆ Technology Xuzhou 221008 China

In light of the possibility of reignition when unsealing the closed fire zones, the occurrence of reignition was simulated by a home-made experimental device, hydrogen variety rule from combustion to unsealing was analyzed, the three-stage generation model of hydrogen during reignition in fire zone was put forward and the probability that hydrogen was taken as an indicator gas was discussed. The results show that: when fire zone is ready to unseal, which is filled with hydrogen at a high concentration, it is more prone to reignite.

关键词： unsealing fire zone reignition hydrogen generation model indicator gas

The Effect of Boron on the Properties of Glucomannan: An Experimental and Molecular Dynamics Simulation Study

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Chinese Journal of Structural Chemistry 2005年第12期24卷 1397-1402页

作者： PANG Jie SUN Yu-Jing li Bin TIAN Shi-Ping CHEN shao-Jun College of Food Science Fu Jian Agriculture And Forestry University Fuzhou Fujian 350002 China Key Laboratory of Photosynthesis and Environmental Molecular Physiology Institute of Botany The Chinese Academy of Sciences Beijing 100093 China College of Food Science and Technology Agriculture University of Middle China Wuhan Hubei 430070 China

The effect of boron on the properties of Konjac Glucomanan （KGM） has been investigated by the method of experiment and molecular dynamic simulation. Upon analysis, the property and structure of KGM are apt to be affected by boron and structural reasons for property change were discussed. In detail, the addition low concentration borax can increase the systematic inherent viscosity, by contrast, high concentration borax has opposite effect on the viscosity. When adding borax, the micropores on KGM film surface decrease or disappear, leading to more compact and uniform on the film surface. The structure of KGM-Boron complex is described as the coordination reaction between KGM and boron. The main reaction points are hydroxyl group on C（6） position of sugar as well as those on C（2） and C（3） positions of mannose with two kinds of complexes formation： B-K2 and KB-K. And KB-K mainly consists of g-b-m.

关键词： glucomannan boron NMR molecular dynamics

Wire and arc additive manufacturing of 4043 Al alloy using a cold metal transfer method

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International Journal of Minerals,Metallurgy and Materials 2020年第6期27卷 783-791页

作者： Zhi-qiang liu Pei-lei Zhang shao-wei li Di Wu Zhi-shui Yu School of Materials Engineering Shanghai University of Engineering ScienceShanghai 201620China Shanghai Collaborative Innovation Center of Laser Advanced Manufacturing Technology Shanghai 201620China

Cold metal transfer plus pulse(C+P)arc was applied in the additive manufacturing of 4043 Al alloy *** in the manufacturing of the parts were *** properties and microstructure of the parts were also *** results showed that welding at a speed of 8 mm/s and a wire feeding speed of 4.0 m/min was suitable to manufacture thin-walled parts,and the reciprocating scanning method could be adopted to manufacture thick-walled *** thin-walled parts of the C+P mode had fewer pores than those of the cold metal transfer(CMT)*** thin-and thick-walled parts of the C+P mode showed maximum tensile strengths of 172 and 178 MPa,*** decreased at the interface and in the coarse dendrite and increased in the refined grain area.

关键词： wire arc additive manufacturing aluminum alloy cold metal transfer microstructure layer deposition

Synthesis and insecticidal evaluation of phytoalexin phenalenones derivatives

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Chinese Chemical Letters 2017年第6期28卷 1228-1231页

作者： Ya-Nan Zhang Yi-An Feng Zhong li Xu-Sheng shao Shanghai Key Laboratory of Chemical Biology School of Pharmacy East China University of Science and Technology Shanghai 20037 China

Phenalenone is a kind of defensive compound biosynthesized inside plants in response to the outside attack such as fungus and nematodes.A set of derivatives encompassing structural modifications on the privileged phenalenone scaffold were synthesized through introduction of phenyl and hydroxy!substitutes at 9-positon and 2-position and assessed their insecticidal activities against armyworm（Mythimna separata Walker） and cowpea aphids[Aphis craccivora）.No obvious insecticidal activities of the synthesized compounds were observed against *** of the 9-phenyl and 2-hydroxy substituted phenalenone analogues showed potential activities against cowpea aphids with 33%-41%mortality at 500 mg/L.

关键词： Phenalenones derivatives Insecticidal activities Structural modifications

Asteroseismic study of the red giant ∈ Ophiuchi

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Research in Astronomy and Astrophysics 2010年第12期10卷 1265-1274页

作者： shao-Lan Bi ling-Huai li Yan-Ke Tang Ning Gai Department of Astronomy Beijing Normal University Beijing 100875 China bisl@*** Department of Astronomy Yale University P.O. Box 208101 New Haven CT 06520-8101 USA Department of Physics Dezhou University Dezhou 253023 China

We test the possible evolutionary tracks of stars with various masses （1.8 M,1.9 M,2.0 M,2.1 M,2.2 M）and metallicities Z（0.008,0.010, 0.012）,including both models with and without convective core *** a given mass and metallicity,the models with a larger overshoot predict a larger radius and age of the *** on the observed frequency of oscillations and the position of Oph on the H-R diagram,we obtain two distinct better-fitting models：the solutions with mass M=1.9 M favor a radius in the range 10.55±0.03 R with an age of 1.01±0.08 Gyr;the solutions with mass M=2.0 M favor a radius in the range 10.74±0.03 R with an age of 0.95±0.11 ***,we investigate the influence of overshooting on the internal structure and the pulsation properties,and find that increasing the convective core overshoot significantly decreases non-radial mode inertia,while also increasing the mode ***,the estimation of stellar mass and age might be modified by convective core penetration.

关键词： stars: oscillations -- stars: individual: e Ophiuchi -- stars: interiors

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温泉水平摆与垂直摆观测资料对比分析

内陆地震 2024年第3期38卷 291-298页

作者：周斌李娇朱文振李晓东毕卉娟新疆维吾尔自治区地震局新疆乌鲁木齐830011

为研究同一台站,同一物理量,以不同观测方式获取资料的一致性,选取温泉老台水平摆和垂直摆为研究对象,研究在不同频段观测数据的一致性与干扰异常的响应特征。分析结果表明:温泉水平摆与垂直摆观测数据稳定、精度高,固体潮记录清晰,在... 详细信息

为研究同一台站,同一物理量,以不同观测方式获取资料的一致性,选取温泉老台水平摆和垂直摆为研究对象,研究在不同频段观测数据的一致性与干扰异常的响应特征。分析结果表明:温泉水平摆与垂直摆观测数据稳定、精度高,固体潮记录清晰,在半日波、日波频段相同分向具有较强的一致性;分钟值至潮汐频段,温泉水平摆与垂直摆观测数据一致性较差,观测数据主要包含的是自身属性信息;年周期频段,温泉水平摆、垂直摆在EW向两者相位差约41天;NS向相位差约14天,相位均滞后于气温。在考虑相位滞后的情况下,温泉水平摆与垂直摆观测一致性较好,均与气温线性相关,故气温是温泉水平摆、垂直摆年周期频段的主要影响因素。

关键词：垂直摆水平摆谱分析相关系数散点图

Dynamic Analysis of Semi-Submersible Production Platform Under the Failure of Mooring lines

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China Ocean Engineering 2021年第1期35卷 84-95页

作者： CHUANG zhen-ju liU She-wen li Chun-zheng LU Yu CHANG Xin Naval Architecture and Ocean Engineering College Dalian Maritime UniversityDalian 116026China

This paper quantitatively studies the transient dynamic response of a semi-submersible production platform with the loss of one or several positioning mooring lines.A semi-submersible platform,production risers,and positioning mooring lines are all included in the numerical *** motion of the semi-submersible platform,tension variation of the remaining mooring lines/risers and the risk of mooring line or riser clashing are all investigated through fully coupled time-domain *** environmental loads are selected from irregular waves and the steady current varying from very rough to extreme sea *** dimension radiation/diffraction theories and Morison’s equation are applied to calculate first-order wave force and second-order mean drift force of floating semi-submersible *** time-domain finite element methods are employed to analyze the behavior of mooring lines and *** show that the failure of mooring lines seriously reduce the platform’s stability *** tension of the rest lines is also increased *** lines which are closer to the failed lines will have larger tension increase to ***-line distance provides practical information for the risk of clashing investigation.

关键词： mooring line failure the transient response of platform tension variation of mooring line risk of lines clashing coupling effect between platform and mooring system

Atmospheric Pb variations in Central Asia since 1955 from Muztagata ice core record, eastern Pamirs

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Chinese Science Bulletin 2006年第16期51卷 1996-2000页

作者： li zhen YAO Tandong TIAN lide XU Baiqing li Yuefang Key Laboratory of Cryosphere and Environment Chinese Academy of Sciences Lanzhou 730000 China Laboratory of Environment and Process on Tibetan Plateau Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China

A Muztagata ice core recovered at 7010 m altitude in East Pamirs provides a Pb concentration record from 1955 to 2000. The result reveals in- creasing Pb concentrations from 1955 to 1993, with two Pb concentration peaks in 1980 and 1993. After 1993, Pb concentrations in ice core show an obvi- ously declining trend. Analysis shows that the lead in the Muztagata ice core mainly came from anthropo- genic emissions from countries in Central Asia, while the local emission had little contribution.

关键词：冰核慕士塔格山铅大气中亚帕米尔高原

A chitosan/amido-graphene oxide-based self-powered humidity sensor enabled by triboelectric effect

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Rare Metals 2021年第8期40卷 1995-2003页

作者： Bo-Hao liu Guang-Zhong Xie Cheng-zhen li Si Wang zhen Yuan Zai-Hua Duan Ya-Dong Jiang Hui-ling Tai State Key Laboratory of Electronic Thin Films and Integrated Devices School of Optoelectronic Science and EngineeringUniversity of Electronic Science and Technology of ChinaChengdu610054China

In this work,amido-graphene oxide(GO-NH_(2))loaded chitosan(CTS)composite material(CTS/GO-NH_(2))that acts as both the triboelectric and sensing film was prepared on rotary fan-shaped triboelectric nanogenerator for humidity *** with the pristine CTSbased triboelectric humidity sensor(CTS-THS)and GONH_(2)-THS,the CTS/GO-NH_(2)-based humidity sensor exhibited higher humidity response and better linearity in the relative humidity(RH)range of 18.7%RH-91.5%*** above results can be explained by the massive exposed and less concealed hydrophilic functional groups of CTS with the help of the wrinkle structure of GO-NH_(2).Meanwhile,the CTS/GO-NH_(2)-THS possessed good repeatability and acceptable hysteresis(~6.2%RH).Finally,a humidity sensing mechanism coupling triboelectric contact charging effect with electrons transfer principle under moisture environment was established to interpret the enhanced humidity sensing performance of the composite film-based *** work demonstrates that CTS/GONH_(2) composite film can be utilized to fabricate humidity sensors based on the triboelectric effect.

关键词： Chitosan Amido-graphene oxide Triboelectric nanogenerator Humidity sensors Hydrogen bonding interaction