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An investigation of electron momentum spectroscopy on the 9a_1 and 5b_2 orbitals of thiophene

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Chinese Science Bulletin 2005年第6期50卷 497-500页

作者： ZHANGShufeng SUGuolin RENXueguang NINGChuangang libin ZHOUHui LIGuiqin DENGJingkang DepartmentofPhysics TsinghuaUniversityBeijing100084China

The electron momentum spectra of outer va- lence orbitals 9a1+5b2 of thiophene (C4H4S) have been stud- ied by binary (e, 2e) electron momentum spectroscopy (EMS), at an impact energy of 1200 eV plus binding energy, and symmetric non-coplanar kinematics. The experimental mo- mentum profile of the summed orbitals is compared with the theoretical momentum distributions calculated using Har- tree-Fock (HF) and density functional theory (DFT) methods with various basis sets. The experimental measurement is well described by the HF and DFT calculations, and the cal- culations using the larger basis sets including diffuse and polarization functions give better descriptions of experi- ments.

关键词：电子动力光谱法噻吩化学结构电子运动轨迹杂环化合物分子原子

Effect Mechanisms of Hygrothermal Environments on Failure of Single-Lap and Double-Lap CFRP-Aluminum Bolted Joints

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Computer Modeling in Engineering & Sciences 2020年第4期123卷 101-127页

作者： Meijuan Shan libin Zhao Wei Huang Fengrui Liu Jianyu Zhang Department of Mechanics School of Civil EngineeringBeijing Jiaotong UniversityBeijing100044China School of Astronautics Beihang UniversityBeijing100191China Hubei Aerospace Flight Vehicle Institute Wuhan430040China College of Aerospace Engineering Chongqing UniversityChongqing400044China

The high demands for load-carrying capability and structural efficiency of composite-metal bolted joints trigger in-depth investigations on failure mechanisms of the joints in hygrothermal ***,few studies have been presented to exhaustively reveal hygrothermal effects on the failure of CFRP-metal bolted joints,which differ from CFRP-CFRP or metal-metal bolted joints because of the remarkably different material properties of CFRPs and *** this paper,hygrothermal effects on tensile failures of single-lap and double-lap CFRP-aluminum bolted joints were experimentally and numerically investigated.A novel numerical model,in which a hygrothermal-included progressive damage model of composites was established and elastic-plastic models of metals were built,was proposed to predict the failures of the CFRP-metal bolted joints in hygrothermal environments and validated by corresponding *** failure mechanisms of single-lap and double-lap CFRP-aluminum bolted joints,under 23°C/Dry and 70°C/Wet conditions,were revealed,*** follows that both the collapse failures of the single-lap and double-lap bolted joints were dominated by the bearing failure of the CFRP hole laminate in the two conditions,indicating that the hygrothermal environment did not change the macro failure modes of the ***,the hygrothermal environment considerably shortened the damage propagation processes and reduced the strength of the ***,the hygrothermal environment weakened the load-transfer capability of the single-lap joint more severely than the double-lap joint because it aggravated the secondary bending effects of the single-lap joint obviously.

关键词： CFRP-metal hybrid structure bolted joint hygrothermal environment effect mechanism numerical model

Variation of crystal orientation during epitaxial growth of dendrites by laser deposition

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Journal of Materials Science & Technology 2018年第4期34卷 732-735页

作者： Guowei Wang Jingjing Liang Yizhou Zhou libin Zhao Tao Jin Xiaofeng Sun Institute of Metal Research Chinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China Xi'an Aero-engine Control Technology Co.Ltd Xi'an 710077China

A nickel-based superalloy was deposited onto a single crystal substrate based on epitaxial laser metal forming （E-LMF）. The microstructure development in two depositions has been researched. For the first time, the crystal orientation of dendrites varying beyond 20° was found when the dendrites deflected in deposition. In addition, a new grain boundary was found between different orientation dendrites in a grain, and the detected grain boundary angle was 23°. The result shows that flowing field in laser pool is responsible for this phenomenon.

关键词： Crystal orientation Epitaxial growth Laser deposition Single crystal Dendrite growth

Long-term trends in foF2 over Moscow ionosonde station: Its estimate and origins

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Chinese Science Bulletin 2012年第12期57卷 1443-1448页

作者： FANG HanXian WENG libin YANG ShengGao WANG SiCheng Institute of Meteorology People＇s Liberation Army University of Science and Technology Nanjing 211101 China State Key Laboratory of Space Weather Chinese Academy of Sciences Beijing 100190 China

We introduce a new approach,using the International Reference Ionosphere 2007(IRI-2007)model and observations from the Moscow ionosonde station,to analyze the long-term trends of ionospheric *** origins,whether natural or manmade, are discussed.A small but significant residual foF2 trend is found,with-0.76 MHz over the past 50 years,but-0.2 MHz after eliminating the most variations caused by solar and geomagnetic activities and the variational earth's magnetic *** find that this slope depends on local time and *** is a pronounced diurnal negative variation in k(annual mean slope of diurnal variations),with much larger absolute values in the morning than during afternoon or evening;the largest k is about-0.0018 per year in spring,and the smallest trend of about-0.0012 per year occurs in ***,the evidence of crucial influences of geomagnetic activity and the earth's magnetic field on the observed trends,as emphasized by the IRI-2007 empirical model,is confirmed,and the effect of CO2 contributions to the trend is also discussed,by cooling the thermospheric temperature or recombining the electron density.

关键词：参考电离层探测仪莫斯科起源估计地球磁场地磁活动临界频率

Cross-laminated Timber(CLT)in China:A State-of-the-Art

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Journal of Bioresources and Bioproducts 2019年第1期4卷 22-30,I0001页

作者： Hao LI Brad Jianhe WANG Peixing WEI libin WANG College of Civil Engineering Nanjing Forestry UniversityNanjing 210037China Ningbo Sino-Canada Low-Carbon Technology Research Institute Ninghai 315600China School of Landscape Architecture Jiangsu Vocational College of Agriculture and ForestryJurong 212400Chin

As a new type of green low-carbon engineered wood product,cross-laminated timber(CLT)is widely used in various types of wooden buildings in Europe and North America,and the number of high-rise wood construction is also *** on the introduction of the structural characteristics of the CLT and the development status of the CLT in developed countries,this paper focused on the review of the status of research and development of the CLT in China,with an emphasis on the breakthrough technologies of new bamboo-wood composite CLT ***,the prospects of the CLT in China were discussed.

关键词： cross-laminated timber(CLT) bamboo wood construction engineering application China

Comparing different spatial interpolation methods to predict the distribution of fishes:A case study of Coilia nasus in the Changjiang River Estuary

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Acta Oceanologica Sinica 2021年第8期40卷 119-132页

作者： Shaoyuan Pan Siquan Tian Xuefang Wang libin Dai Chunxia Gao Jianfeng Tong College of Marine Sciences Shanghai Ocean UniversityShanghai 201306China National Distant-water Fisheries Engineering Research Center Shanghai 201306China Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources Ministry of EducationShanghai 201306China Key Laboratory of Oceanic Fisheries Exploitation Ministry of Agriculture and Rural AffairsShanghai 201306China Scientific Observing and Experimental Station of Oceanic Fishery Resources Ministry of Agriculture and Rural AffairsShanghai 201306China

Spatial-temporal distribution of marine fishes is strongly influenced by environmental *** obtain a more continuous distribution of these variables usually measured by stationary sampling designs,spatial interpolation methods(SIMs)is usually ***,different SIMs may obtain varied estimation values with significant differences,thus affecting the prediction of fish spatial *** this study,different SIMs were used to obtain continuous environmental variables(water depth,water temperature,salinity,dissolved oxygen(DO),p H,chlorophyll a and chemical oxygen demand(COD))in the Changjiang River Estuary(CRE),including inverse distance weighted(IDW)interpolation,ordinary Kriging(OK)(semivariogram model:exponential(OKE),Gaussian(OKG)and spherical(OKS))and radial basis function(RBF)(regularized spline function(RS)and tension spline function(TS)).The accuracy and effect of SIMs were cross-validated,and two-stage generalized additive model(GAM)was used to predict the distribution of Coilia nasus from 2012 to 2014 in *** and COD were removed before model prediction due to their autocorrelation coefficient based on variance inflation factors *** showed that the estimated values of environmental variables obtained by the different SIMs differed(i.e.,mean values,range etc.).Cross-validation revealed that the most suitable SIMs of water depth and chlorophyll a was IDW,water temperature and salinity was RS,and p H was ***,different interpolation results affected the predicted spatial distribution of Coilia nasus in the *** mean values of the predicted abundance were similar,but the differences between and among the maximum value were *** showed that different SIMs can affect estimated values of the environmental variables in the CRE(especially salinity).These variations further suggest that the most applicable SIMs to each variable will also ***,it is necessary to take these potential impacts into consideration when

关键词： the Changjiang River Estuary marine environmental factors spatial interpolation method Coilia nasus spatial distribution

An enhanced hybrid and adaptive meta-model based global optimization algorithm for engineering optimization problems

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Science China(Technological Sciences) 2016年第8期59卷 1147-1155页

作者： ZHOU Guan DUAN libin ZHAO WanZhong WANG ChunYan MA ZhengDong GU JiChao College of Energy and Power Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body Hunan University Changsha 410082 China Department of Mechanical Engineering and Applied Mechanics University of Michigan Ann Arbor Michigan 48109 USA

Due to the good balance between high efficiency and accuracy, meta-model based optimization algorithm is an important global optimization category and has been widely applied. To better solve the highly nonlinear and computation intensive en- gineering optimization problems, an enhanced hybrid and adaptive meta-model based global optimization （E-HAM） is first proposed in this work. Important region update method （IRU） and different sampling size strategies are proposed in the opti- mization method to enhance the performance. By applying self-moving and scaling strategy, the important region will be up- dated adaptively according to the search results to improve the resulting precision and convergence rate. Rough sampling strategy and intensive sampling strategy are applied at different stages of the optimization to improve the search efficiently and avoid results prematurely gathering in a small design space. The effectiveness of the new optimization algorithm is verified by comparing to six optimization methods with different variables bench mark optimization problems. The E-HAM optimization method is then applied to optimize the design parameters of the practical negative Poisson＇s ratio （NPR） crash box in this work. The results indicate that the proposed E-HAM has high accuracy and efficiency in optimizing the computation intensive prob- lems and can be widely used in engineering industry.

关键词： global optimization meta-modeling important region update method crash box

Zr-xNb-4Sn alloys with low Young's modulus and magnetic susceptibility for biomedical implants

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Progress in Natural Science:Materials International 2021年第5期31卷 772-778页

作者： Renhao Xue Dong Wang Yueyan Tian Jiang Wang libin Liu Ligang Zhang School of Material Science and Engineering Central South University Guangxi Key Laboratory of Information Materials Guilin University of Electronic Technology State Key Laboratory of Powder Metallurgy Central South University

The microstructure,mechanical and magnetic properties of Zr-x(8,9,10,wt.%)Nb-4 Sn alloys were investigated to obtain novel Zr-based alloy with low Young’s modulus and magnetic susceptibility for biomedical *** homogenization annealing,hot forging and solution annealing,Zr-8 Nb-4 Sn,Zr-9 Nb-4 Sn and Zr-10 Nb-4 Sn alloys were composed of β+α" phase,β+α" phase,β+ω phase,*** temperature at which the α" and ωphase were transformed into β phase during the heating process was about 200 ℃ and the phase transformation temperature decreased with the increase of Nb *** all the Zr-x(x=8,9,10)Nb-4 Sn(wt.%) alloys,Zr-9 Nb-4 Sn alloy had the lowest Young’s modulus of 46.6 GPa and the low magnetic susceptibility of1.294×10-6cm~3 g-1,which has a good application prospect for biomedical applications.

关键词： Zirconium-based alloys Microstructure Mechanical properties Phase transformation Biomedical materials

Probabilistic stability analysis of Bazimen landslide with monitored rainfall data and water level fluctuations in Three Gorges Reservoir, China

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Frontiers of Structural and Civil Engineering 2020年第5期14卷 1247-1261页

作者： Wengang ZHANG libin TANG Hongrui LI Lin WANG Longfei CHENG Tingqiang ZHOU Xiang CHEN School of Civil Engineering Chongqing UniversityChongqing 400045China Key Laboratory of New Technology for Construction of Cities in Mountain Area Chongqing UniversityChongqing 400045China National Joint Engineering Research Center of Geohazards Prevention in the Reservoir Areas Chongqing UniversityChongqing 400045China School of Civil Engineering Chongqing Three Gorges UniversityChongqing 404100China

Landslide is a common geological hazard in reservoir areas and may cause great damage to local residents’life and *** is widely accepted that rainfall and periodic variation of water level are the two main factors triggering reservoir *** this study,the Bazimen landslide located in the Three Gorges Reservoir(TGR)was back-analyzed as a case *** on the statistical features of the last 3-year monitored data and field instrumentations,the landslide susceptibility in an annual cycle and four representative periods was investigated via the deterministic and probabilistic analysis,*** results indicate that the fluctuation of the reservoir water level plays a pivotal role in inducing slope failures,for the minimum stability coefficient occurs at the rapid decline period of water *** probabilistic analysis results reveal that the initial sliding surface is the most important area influencing the occurrence of landslide,compared with other parts in the *** seepage calculations from probabilistic analysis imply that rainfall is a relatively inferior factor affecting slope *** study aims to provide preliminary guidance on risk management and early warning in the TGR area.

关键词： reliability analysis Bazimen landslide rainfall reservoir water level slope stability