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中国有色金属学会会刊：英文版 2004年第z1期14卷 413-419页

作者： ZOU Yang PAN Chun-xu fu Qiang Department of Physics & Center for Electron Microscopy Wuhan University Wuhan 430063 China Department of Physics & Center for Electron Microscopy Wuhan University Wuhan 430063 China Department of Physics & Center for Nano-Science and Technology Wuhan University Wuhan 430063 China

The present work studied the corrosion properties around the fusion boundaries of 2.25Cr-1Mo steel with stainless steel strip overlay joints under as welded condition and after post-weld heat treatment (PWHT) in H2 S containing solution (NACE TM-01-77 standard) with different time. An in-situ observation method was introduced for evaluating corrosive progress in the fusion boundary in H2 S containing solution, that is, the samples were marked firstly at the boundary and then treated in the solution for variant time. Each time after the corrosion treatment, the observations were kept to focus at the same marked area by using scanning electron microscopy (SEM) to observe the corrosion progress. The results reveal that the fusion boundary is the worst region for corrosion resistance when comparing with other boundaries, and a broad fusion boundary has a stronger resistance for "hydrogen induced disbonding" than a narrow one.

关键词： dissimilar steel welding fusion boundary H2S corrosion post-weld heat treatment

Thermodynamics and performance of Al/CuO nanothermite with different storage time

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Defence Technology（防务技术） 2021年第3期17卷 741-747页

作者： Cheng-ai Wang Jian-bing xu Yun Shen Yue-ting Wang Teng-long Yang ze-hua Zhang fu-wei Li Rui-qi Shen Ying-hua Ye School of Chemical Engineering Nanjing University of Science&TechnologyNanjing210094People’s Republic of China Micro-Nano Energetic Devices Key Laboratory of MIIT Nanjing210094People’s Republic of China

The storage stability of energetic materials is important for its application. Here, the storage stability of Al/CuO nanothermite, which was prepared by electrospray method and stored with different storage time, was systematically researched. The activation energy of Al/CuO nanothermite was calculated by differential scanning calorimetry(DSC). The ignition temperature and the curve pressure history of Al/Cu O nanothermite was measured using ignition temperature measuring device and constant-volume pressurization tests, respectively. further, the thermites were characterized by X-ray Diffractometer(XRD), X-ray photoelectron spectroscopy(XPS), scanning electron microscope(SEM) and Transmission electron microscopy(TEM). The results show that the morphology of the thermites did not change significantly. The activation energy was decreased from 254.1 k J/mol to 181.8 k J/mol after storage for 13 months. When stored for 0, 7 and 13 months, the peak pressures of Al/CuO nanothermite were 685.8 k Pa,626.3 k Pa and 625.5 k Pa, respectively. In addition to the ignition temperature, it was 775 ℃, 739 ℃ and754 ℃, respectively. This result indicated that the ignition and combustion properties of Al/CuO nanothermite are obviously reduced when stored for a long time, at room temperature.

关键词： Al/CuO Nanothermites Stroage stability Thermodynamics

The Aviation Technology Two-Sided Matching with the Expected Time Based on the Probabilistic Linguistic Preference Relations

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Journal of the Operations Research Society of China 2020年第1期8卷 45-77页

作者： Bo Li Yi-Xin Zhang ze-Shui xu Institute for Disaster Management and Reconstruction Sichuan UniversityChengdu 610207China Business School State Key Laboratory of Hydraulics and Mountain River EngineeringSichuan UniversityChengdu 610064China School of Computer Science University of ManchesterManchester M139PLUnited Kingdom

The two-sided matching has been widely applied to the decision-making problems in the field of *** the limited working experience,the two-sided agents usually cannot provide the preference order directly for the opposite agent,but rather to provide the preference relations in the form of linguistic *** preference relations based on probabilistic linguistic term sets(PLTSs)not only allowagents to provide the evaluation with multiple linguistic terms,but also present the different preference degrees for linguistic *** the diversities of the agents,they may provide their preference relations in the form of the probabilistic linguistic preference relation(PLPR)or the probabilistic linguistic multiplicative preference relation(PLMPR).For two-sided matching with the expected time,we first provide the concept of the time satisfaction degree(TSD).Then,we transform the preference relations in different forms into the unified preference relations(u-PRs).The consistency index to measure the consistency of u-PRs is ***,the acceptable consistent u-PRs are constructed,and an algorithm is proposed to modify the unacceptable consistent ***,we present the whole two-sided matching decisionmaking process with the acceptable consistent ***,a case about aviation technology suppliers and demanders matching is presented to exhibit the rationality and practicality of the proposed *** analyses and discussions are provided to further demonstrate the feasibility and effectiveness of the proposed method.

关键词： Two-sided matching Time satisfaction degree Probabilistic linguistic term sets Preference relation Aviation technology

Enhanced hepatotoxicity induced by repeated exposure to polychlorinated biphenyls and 2,3,7,8-tetrachlorodibenzo-p-dioxin in combination in male rats

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Journal of Environmental Sciences 2011年第1期23卷 119-124页

作者： Yimei Wang Chunfeng Lu Zhiguo Sheng Gang Liu ze fu Benzhan Zhu Shuangqing Peng Evaluation and Research Center for Toxicology Institute of Disease Control and Prevention Academy of Military Medical Sciences Beijing 100071 China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Department of Pharmacology Basic Medical College Jiamusi University Jiamusi 154007 China

2,3,7,8-Tetrachlorodibenzo-p-dioxin （TCDD） and polychlorinated biphenyls （PCBs） are among persistent polyhalogenated aromatic hydrocarbons that exist as complex mixtures in the environment worldwide. The present study was attempted to investigate the hepatotoxicity following repeated exposure to TCDD and PCBs in combination in male rats, and to reveal the involvement of potential mechanisms. Male Sprague-Dawley rats were exposed to TCDD （10 Ixg/kg） and Aroclor 1254 （10 mg/kg, a representative mixture of PCBs） alone or in combination by intragastric administration. After 12-day exposure, all treatments produced significant hepatotoxicity as characterized by changes of plasma biochemistry and histopathological changes. These effects were more prominent in the combined group. furthermore, all treatments induced hepatic cytochrome P450 1A1 （CYP1A1） expression, and the maximal level of CYP1A1 expression was observed in the combined group, as in the case of the most severe hepatotoxicity evoked by the combined exposure. These findings indicated that the hepatotoxicity induced by TCDD and Aroclor 1254 might be ascribed to the high expression of hepatic CYP1A1. The present study demonstrates the enhanced hepatotoxicity after exposure to TCDD and PCBs in combination in rats.

关键词： 2,3,7,8-tetrachlorodibenzo-p-dioxin polychlorinated biphenyls combined exposure hepatotoxicity

The runoff characteristics under simulated rainfall on purple soil sloping cropland

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Chinese Journal Of Geochemistry 2011年第3期30卷 317-322页

作者： xu Pei fu Bin Key Laboratory of Mountain Surface Process and Hazards Chinese Academy of Sciences Chengdu 610041 China Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China

Rainfall runoff is a critical hydrological process related to soil erosion and agricultural non-point pollu-tion. In this study, 25 simulation experiments on rainfall were carried out in five runoff plots. Rape (Brassica campestris) was planted on the downslope of the plots. Experiments were conducted when the vegetation coverage reached 80%. Each plot was subjected to five rainfall events differing in intensity. The results showed: (1) the runoff coefficients of overland flow and subsurface flow were less than 0.6 and 0.005, respectively; (2) the discharge of overland flow was the quadratic function of time; (3) runoff coefficient was the function of slope gradient and rain-fall intensity. When the slope gradient increased from 8.7% to 46.6%, the runoff coefficient of overland flow first increased and then decreased. The runoff coefficient reached the maximum when the slope gradient was within the range of 17.6%-36.4%; and (4) the process of subsurface flow generation included the increasing phase and reces-sion phase. Discharge was a logarithm function of time in the increasing phase, and an exponential function in the recession phase. Runoff coefficient of subsurface flow decreased first and then increased when the slope gradient varied from 8.7% to 46.6% and was not correlated with rainfall intensity.

关键词：模拟降雨径流特性紫色土坡耕地农业非点源污染径流系数降雨强度径流小区

Development and experimental characterization of a robotic butterfly with a mass shifter

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Biomimetic Intelligence & Robotics 2022年第4期2卷 39-47页

作者： Haifeng Huang Wei He ze Chen Tao Niu Qiang fu School of Intelligence Science and Technology University of Science and Technology BeijingBeijing 100083China Institute of Artificial Intelligence University of Science and Technology BeijingBeijing 100083China

The development of biomimetic aerial robots has emerged as a new solution for studying the flight mechanisms of flying *** study designs a biomimetic robotic butterfly steered via a mass shift mechanism named USTButterfly-II and investigates its flight characteristics using an optical tracking ***,a planar fourbar linkage was used to drive the flapping of the designed butterfly-like artificial ***,an innovative tailless steering control method was proposed based on a mass shift ***,the wing kinematics and motion trajectory of the USTButterfly-II were measured using a multi-camera motion capture system,and some difficult-to-measure flapping aerodynamic parameters,such as the instantaneous net lift and thrust coefficients,were *** findings present a novel experimental framework that not only provides effective data support for the design and improvement of the robotic butterfly but also benefits the study of biological butterfly flight mechanisms.

关键词： Robotic butterfly Flapping-wing aerial robot Bionic robot Tailless control

Fern botanist Ren-Chang Ching and his taxonomic system

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Protein & Cell 2021年第12期12卷 903-905页

作者： xunfeng xu Lei fu Zhejiang Normal University Jinhua 321004China

Ren-Chang Ching(秦仁昌,1898-1986)is a famous botanist in China(Fig.1).He is known as the father of Chinese pteridology,having done extensive research on *** Ren-Chang Ching System established by him has made great con... 详细信息

关键词： has taxonomy Ching

A Four-Equation Eddy-Viscosity Approach for Modeling Bypass Transition

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Advances in Applied Mathematics and Mechanics 2014年第4期6卷 523-538页

作者： Guoliang xu Song fu China Aerodynamics Research and Development Center Mianyang 621000China School of Aerospace Tsinghua UniversityBeijing 100084China

It is very important to predict the bypass transition in the simulation of flows through *** paper presents a four-equation eddy-viscosity turbulence transition model for prediction of bypass *** is based on the SST turbulence model and the laminar kinetic energy concept.A transport equation for the non-turbulent viscosity is proposed to predict the development of the laminar kinetic energy in the pre-transitional boundary layer flow which has been observed in *** turbulence breakdown process is then captured with an intermittency transport equation in the transitional *** performance of this new transition model is validated through the experimental cases of T3AM,T3A and *** in this paper show that the new transition model can reach good agreement in predicting bypass transition,and is compatible with modern CFD software by using local variables.

关键词： Bypass transition non-turbulent viscosity free stream turbulence turbulence model

Fission law of solitary waves propagating over sharply variable topography

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Journal of Hydrodynamics 2020年第4期32卷 727-734页

作者： Da-lin Tan Ji-fu Zhou xu Wang Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Engineering Sciences University of Chinese Academy of SciencesBeijing 100049China

The fission of solitary waves propagating over variable topography is *** previous theories,to predict the number and the amplitudes of disintegrated solitons in the wave packet generated from a solitary wave,the parameters of the water environment and the incident solitary wave are ***,it is difficult to measure these parameters in the ocean because of their temporal and spatial *** this paper,a fission law,in the form of the expressions of the number and the amplitudes of the disintegrated solitons,is derived from the partial information available on the wave *** analysis shows that the law is suitable fbr describing the fission of both surface and internal solitary waves and is also applicable to the cases of wave damping and wave *** between the model output and the results from laboratory experiments,numerical simulations and field observations available in the literature demonstrate that the fission law can efficiently estimate the number and the amplitudes of solitons in the wave packet generated by a solitary wave.

关键词： Fission law solitary wave packet wave breaking

Energy absorption behaviors of a novel buffer lander-leg with Yoshimura core

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Chinese Journal of Aeronautics 2024年第4期37卷 333-342页

作者： Yan xu He HUANG Chao ZHANG Rongji fu School of Aeronautics and Astronautics Zhejiang UniversityHangzhou 310027China School of Mechanics Civil Engineering and Architecture Northwestern Polytechnical UniversityXi’an 710072China

In the current soft-landing system,the lander-leg and the buffer are two independent parts which may cause weight *** traditional mechanical buffers also have their own shortcomings such as small buffer stroke and being non-reusable.A Novel Buffer Lander-leg with Yoshimura core (NBLY) is proposed in this paper,inspired by the Buckling Restrained Brace(BRB).The design details of NBLY and parameter definitions of the core are *** finite element analysis modes have been employed to analyze the nonlinear mechanical behaviors of NBLY subjected to the cyclic *** with four different core styles of hexagon,octagon,dodecagon and hexadecagon are analyzed and *** restraining ratio and cumulative dissipation energy ratio have been obtained to evaluate the energy absorption *** results show that the origami pattern has significant influences on the deformation ductility,plastic energy absorbing and axial load transferring to the *** NBLY with octagon core has outstanding properties,especially the hysteretic energy dissipation and enhancement of compression *** interaction mechanism between the core and encasing member constrains the deformation extensions and contributes to the frictional energy dissipation of the *** paper provides a new conceptual design of buffer lander-leg for soft-landing *** can realize the reuse function as a buffer lander-leg with better loading-bearing and energy absorption behaviors.

关键词： Lander-leg structure Origami Energy absorption Cyclic loading Finite element analysis