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Effect of basic fibroblast growth factor and danshen on bcl-2 and p53 mRNA expression in the brain of rats exposed to repeated, high, positive acceleration (+Gz)

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Neural Regeneration Research 2008年第7期3卷 747-750页

作者： hongjin liu qing cai Military Researching Center of Aeropathy Air-force General Hospital of Chinese PLA Beijing 100036 China

BACKGROUND： Both animal experiments and clinical studies have shown that basic fibroblast growth factor （bFGF） and danshen （Salvia miltiorrhiza） can exhibit protective effects on ischemia-reperfusion cerebral injury. OBJECTIVE： To test whether bFGF and danshen can protect cerebral injury induced by exposure to repeated, high, positive acceleration （＋Gz） in an animal model and to analyze the possible mechanisms. DESIGN, TIME AND SETTING： Randomized controlled animal study. The experiment was performed at the Research Center for Molecular Biology, Air-force General Hospital of Chinese PLA from April to August 2000. MATERIALS： A total of 20 clean grade, healthy, Sprague Dawley rats of both genders, weighing （200 ± 15） g, were provided by our experimental animal center. Rats were randomly divided into 5 groups： the control group, ＋Gz exposure group, bFGF group, danshen group, and saline group, with 4 animals per group. bFGF （Beijing Bailuyuan Biotechnology Co. Ltd.） and danshen solution （Shanghai Zhongxi Pharmaceutical Co. Ltd.） were used. METHODS： All rats were fixed on a rotary arm of a centrifugal apparatus （2 m in radius） with their heads oriented towards the center of the apparatus. Except for rats in the control group, the value of ＋Gz exposure was ＋14 Gz with an acceleration rate of 1.5 G/s. The peak force lasted for 45 seconds. ＋Gz exposure was performed three times with intervals of 30 minutes. Rats in the control group received the same ＋Gz procedure, but the G value was ＋1 Gz. Rats in bFGF group and danshen group were intraperitoneally injected with 100 μg/kg bFGF or 15 g/kg danshen solution, respectively, at 30 minutes prior to centrifugation and immediately after centrifugation. Rats in saline group were injected with the same volume of saline. Six hours after exposure, rats were decapitated. One hemisphere was preserved in liquid nitrogen for RNA extraction and the other was processed for apoptosis detection. MAIN OUTCOME MEASURES： mRNA levels of

关键词： positive acceleration rats apoptosis bcl-2 p53 gene expression basic fibroblast growth factor danshen

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Effect of reduction pretreatment process on evolution of micro-porosity in 42CrMo billet

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Journal of Iron and Steel Research International 2021年第4期28卷 413-423页

作者： Zhen Ning Wei Yu Hong-qiang liu qing-wu cai Collaborative Innovation Centre of Steel Technology University of Science and Technology BeijingBeijing 100083China HBIS Group Co. Ltd.Shijiazhuang 050000HebeiChina

Reduction pretreatment(RP)process,which is implemented after the billet is completely solidified,is an alternative process to further improve billet *** element method and experiment were used to investigate the effect of the RP process on the internal quality of 42CrMo *** ultrasonic testing technology was used to study the influence of the RP process on the *** a three-dimensional finite element model,the mechanism of the RP process on the porosity closure was *** experimental results show that the RP process eliminates the macro-porosities of the billet *** number of micro-porosities in the billets is effectively reduced,and the increase in deformation contributes to the reduction in *** with isothermal rolling,the RP process leads to a larger equivalent strain and hydrostatic integration in the billet center because of the temperature gradient,and the effect of the temperature gradient is greater with the increase in *** closure effect of micro-porosity is related not only to the stress state,but also to the distribution of *** increase in three-dimensional compressive stress is beneficial to the porosity *** the micro-porosities distributed densely,excessive stress could induce micro-porosity coalescence,which has the risk of inducing cracks.

关键词： Reduction pretreatment Temperature gradient Large deformation Micro-porosity Ultrasonic testing

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A Light Weight Traffic Volume Prediction Approach Based on Finite Traffic Volume Data

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Journal of Systems Science and Systems Engineering 2023年第5期32卷 603-622页

作者： Xing Su Minghui Fan Zhi cai qing liu Xiaojun Zhang Faculty of Information Technology Bering University of TechnologyBeijing100124China Shanghai Ocean University Shanghai201306China Academy of Opto-electronics Chinese Academy of SciencesBeijing100094China

As one of the key technologies of intelligent transportation systems, short-term traffic volume prediction plays an increasingly important role in solving urban traffic problems. In the last decade, many approaches were proposed for the traffic volume prediction from different perspectives. However, most of these approaches are based on a large amount of historical data. When there are only finite collected traffic data, they cannot be well trained, so the prediction accuracy of these approaches will be poor. In this paper, a tensor model is proposed to capture the change patterns of continuous traffic volumes. From collected traffic volume data, the element data are extracted to update the corresponding elements of the tensor model. Then, a tucker decomposition and gradient descent based algorithm is employed to impute the missing elements of the tensor model. After missing element imputation, the tensor model can be directly applied to the short-term traffic volume prediction through searching the corresponding elements of the model and the storage cost of the model is low. Our model is evaluated on real traffic volume data from PeMS dataset, which indicates that our model has higher traffic volume prediction accuracy than other approaches in the situation of finite traffic volume data.

关键词： Short-term traffic volume prediction tensor Tucker decomposition finite traffic volume data

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The Local Bifurcation and Stability of Nontrivial Steady States of a Logistic Type of Chemotaxis

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Acta Mathematicae Applicatae Sinica 2017年第3期33卷 799-808页

作者： Chen-qing cai Qian xu Xiao-lin liu School of Sciences Zhejiang A & F University Hangzhou 311300 China Department of Basic Courses Beingjing Union University Beijing 100101 China

Chemotaxis is a type of oriented movement of cells in response to the concentration gradient of chemical substances in their environment. We consider local existence and stability of nontrivial steady states of a logistic type of chemotaxis. We carry out the bifurcation theory to obtain the local existence of the steady state and apply the expansion method on the chemotaxis to investigate the bifurcation direction. Moreover, by applying the bifurcation direction, we obtain the bifurcating steady state is stable when the bifurcation curve turns to right under certain conditions.

关键词： local bifurcation steady states stability

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Hot deformation characterization and processing map of Cu-10 %Fe-1.5 %Ag in situ composite

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Rare Metals 2017年第11期36卷 912-918页

作者： Jun-qing Guo He Yang Ping liu Zhi-Wei cai State Key Laboratory of Solidification Processing Northwestern Polytechnical University School of Materials Science and Engineering University of Shanghai for Science and Technology School of Materials Science and Engineering University of Henan Science and Technology

The Cu-10 %Fe-1.5 %Ag in situ composite with high strength, high conductivity and low cost was prepared, and its hot deformation behavior was investi- gated by isothermal compression test with true strain of 0.69, temperature range of 750-950℃ and strain rate of 0.002-1.000 s-1. The flow stress-strain response shows the characterization of dynamic recrystallization （DRX）, and the peak stress increases gradually with deformation tem- perature decreasing and strain rate increasing. The defor- mation activation energy of the composite for DRX is calculated as 241.864 ***1-1. The constitutive relation of the composite was got by Arrhenius equation. Further- more, according to the dynamic material modeling and Kumar-Prasad＇s instability criteria, the processing map was constructed and the unsafe regions for hot deformation were analyzed. Based on the processing map and microstructural evolution, the optimal parameter range for hot deformation processing is 750-863℃ at the strain rate of 0.002-0.013 s-1.

关键词： Cu-10 %Fe-1.5 %Ag in situ composite Hotcompression test Deformation characterization Processingmap Dynamic recrystallization

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3D contaminant migration model with consolidation dependent transport coefficients

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Acta Mechanica Sinica 2012年第1期28卷 151-163页

作者： Lu Huang Cheng-Gang Zhao Yan liu Guo-qing cai School of Civil Engineering&Architecture Southwest Petroleum University610500 ChengduChina Department of Civil Engineering&Architecture Beijing Jiaotong University100044 BeijingChina

Soil consolidation would induce variations of its transport coefficients such as hydraulic conductivity and diffusion coefficient. This paper presents a study of the influence of barrier consolidation on transport coefficients, and a 3D transport model based on mixture theory is proposed for describing the liners that involve circular defects in the geomembrane. The elastoplastic ALPHA model is revised by using the spatially mobilized plane （SMP） criterion for simulating the deformation of the soils. Then, the 3D model coupling the nonlinear consolidation and contaminant advection-diffusion is solved using the finite element software ABAQUS. The results show that the importance of reducing the defect size in the geomembrane and the liner porosity to control the contaminant concentration increase

关键词： Porosity Contaminant transport. Consolidation Nonlinearity Elastoplasticity

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Combustion Characteristics and Kinetics of Anthracite Blending with Pine Sawdust

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Journal of Iron and Steel Research International 2015年第9期22卷 812-817页

作者： Guo-qing liu qing-cai liu Xiao-qing WANG Fei MENG Shan REN Zhen-peng JI College of Materials Science and Engineering Chongqing University

The combustion characteristics and kinetics of anthracite,pine sawdust and their blends were investigated under combustion condition by thermogravimetric analysis,*** fractions of pine sawdust in the blended samples were set to be 30%,50%,and 80%.The results showed that the ignition and burnout temperatures of pine sawdust were lower and the maximum combustion rate was higher than those of *** the increase of pine sawdust content,the ignition temperature and burnout temperature of the blends decreased,while the maximum mass loss rate and the combustible index of the blends increased;that is,the comprehensive combustion property became *** kinetic parameters for the blends combustion under air condition were calculated based on experimental results using Coats-Redfern *** the pine sawdust content varied in the range of 30%-80%,the combustion processes of these blends could be divided into two stages and the combustion reactions belong to the first-order *** values of apparent activation energy at two individual stages decreased from 68.78to47.28kJ·mol-1 and from 113.53 to 46.43kJ·mol-1,respectively.

关键词： pine sawdust anthracite thermogravimetric analysis combustion characteristics apparent activation energy

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Heredity Characteristic From Hot Rolled Microstructure to Annealed Microstructure in High Strength TRIP Steels

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Journal of Iron and Steel Research International 2010年第10期17卷 38-44页

作者： XIONG Zi-liu cai qing-wu JIANG Hai-tao National Engineer Research Center of Advanced Rolling University of Science and Technology Beijing Beijing 100083 China

The influence of hot rolled process on microstructure in TRIP （transformation induced plasticity） steel and the heredity characteristic from the hot rolled microstructure to annealed microstructure are investigated. The results show that there are two kinds of hot rolled microstructures at different coiling temperatures. One is composed of coarse grains of ferrite, pearlite and bainite, and the other is composed of small grains of ferrite, bainite and austen- ite, After annealing, the first kind of hot rolled microstructure is greatly refined, and volume fraction, and carbon content of austenite increase significantly. However, it has little changes in grain size, volume fraction and carbon content of austenite after the second kind of hot roiled sheet is annealed. There are also differences in distribution of retained austenite between the two annealed microstructures observed by EBSD and TEM technology. Retained aus- tenite in the first annealed microstructure is distributed mainly on the inside of the polygonal ferrite in the form of spot, only little retained austenite is located on bainte ferrite boundary, however retained austenite in the second an- nealing microstructure is located in several places, such as inside of polygonal ferrite, polygonal ferrite boundary, and bainte ferrite boundary.

关键词： TRIP steel hot roiled microstructure heredity microstructure annealing

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Abundance analysis of Barium stars

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Chinese Journal of Astronomy and Astrophysics 2009年第4期9卷 431-448页

作者： Guo-qing liu Yan-Chun Liang Li-cai Deng National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

We obtain the chemical abundances of six barium stars and two CH subgiant stars based on the high signal-to-noise ratio and high resolution EcheUe spectra. The neu-Iron capture process elements Y, Zr, Ba, La and Eu show obvious overabundances relative to the Sun, for example, their [Ba/Fe] values are from 0.45 to 1.27. Other elements, including Na, Mg, A1, Si, Ca, Sc, Ti, V, Cr, Mn and Ni, show comparable abundances to the Solar ones, and their [Fe/H] covers a range from -0.40 to 0.21, which means they belong to the Galactic disk. The predictions of the theoretical model of wind accretion for binary systems can explain the observed abundance patterns of the neutron capture process elements in these stars, which means that their overabundant heavy-elements could be caused by accreting the ejecta of AGB stars, the progenitors of present-day white dwarf companions in binary systems.

关键词： stars abundances-stars atmospheres-stars chemically peculiar-stars evolution-binaries spectroscopic

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Strain-Modulated Photoelectric Responses from a Flexibleα-In_(2)Se_(3)/3R MoS_(2)Heterojunction

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Nano-Micro Letters 2021年第7期13卷 1-11页

作者： Weifan cai Jingyuan Wang Yongmin He Sheng liu Qihua Xiong Zheng liu qing Zhang Center for Micro-and Nano-Electronics School of Electrical and Electronic EngineeringNanyang Technological UniversitySingapore 639798Singapore School of Materials Science and Engineering Nanyang Technological UniversitySingapore 639798Singapore Division of Physics and Applied Physics School of Physical and Mathematical SciencesNanyang Technological UniversitySingapore 639798Singapore

Semiconducting piezoelectricα-In_(2)Se_(3) and 3R MoS_(2) have attracted tremendous attention due to their unique electronic *** van der Waals(vdWs)hetero-structures constructed withα-In_(2)Se_(3)and 3R MoS_(2)flakes have shown promising applications in optoelectronics and ***,we present the first flexibleα-In_(2)Se_(3)/3R MoS_(2)vdWs p-n heterojunction devices for photodetection from the visible to near infrared *** heterojunction devices exhibit an ultrahigh photoresponsivity of 2.9×10^(3)A W^(−1) and a substantial specific detectivity of 6.2×10^(10) Jones under a compressive strain of−0.26%.The photocurrent can be increased by 64%under a tensile strain of+0.35%,due to the heterojunction energy band modulation by piezoelectric polarization charges at the hetero-junction *** work demonstrates a feasible approach to enhancement of α-In_(2)Se_(3)/3R MoS_(2) photoelectric response through an appropriate mechanical stimulus.

关键词： α-In_(2)Se_(3)/3R MoS_(2)heterojunction Flexible Self-powered photodetector Strain modulation Piezoelectric charge

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