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Influence of kavain on hepatic ultrastructure

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World Journal of Gastroenterology 2008年第4期14卷 541-546页

作者： shuang fu Emine Korkmaz Filip Braet Quan Ngo Iqbal Ramzan Faculty of Pharmacy The Universityof Sydney NSW 2006 Australia Australian Key Centre forMicroscopy and Microanalysis Electron Microscopy Unit TheUniversity of Sydney NSW 2006 Australia Faculty of Medicine The University of Sydney NSW2006 Australia

AIM: To investigate whether the major kavalactone kavain imposes adverse effects on the liver ultrastructure and function by affecting vascular and microvascular architecture and altering hepatocellular morphology. METHODS: Kavain solution (10 μg/mL or 43.5 μmol/L) was perfused for 2 h in isolated rat livers. After standard fi xation and tissue preparation,the samples were examined by scanning electron microscopy (SEM),transmission electron microscopy (TEM),and light microscopy (LM). RESULTS: LM,SEM,and TEM examinations indicated kavain-treated rat livers (n = 4) displayed severe vascular and endothelial damage compared to control livers (n = 4). CONCLUSION: The data so far support the hypothesis that kavain induces adverse effects on liver; additional investigations with other kavalactones and their effects on liver are urgently needed.

关键词： Kava Kavalactones Kavain Liver Electronmicroscopy

Preparation of Inoculants Used in Superalloy and Analysis of the Atomic Matching Models

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Journal of Materials Science & Technology 2013年第4期29卷 387-392页

作者： fu Wang Jun Zhang Taiwen Huang lin Liu Hengzhi fu State Key Laboratory of Solidification Processing Northwestern Polytechnical University

The mechanisms of grain refinement were investigated on two kinds of grain refiners used in Ni-Fe based superalloys and complete atomic matching modes were constructed in this study. It is found that there are at least three matching crystal planes having the small lattice disregistry between the refiner and the nucleated phase, which can lead to grain refinement of γ matrix. The results indicate that the （0001）, （01-10） planes of CrFeNb have a fine crystallographic matching relationship with the （111）, （110） planes of γ matrix. The disregistry of （0001）CrFeNb//（111 ）γ, （011-0）CrFeNb//（111）γ and （0110）CrFeNb//（110）γ is 3.34%, 6.60% and 5.90%, respectively. The （0001）, （0110） planes of Co3FeNb2 and （111）, （110） planes of γ matrix also have this relationship. The disregistry of （0001）Co3FeNb2//（111）γ, （0001）Co3FeNb2//（110）γ, （0110）Co3FeNb2//（111）γ and （0110）Co3FeNb2//（110）γ, is 4.45%, 9.35%, 8.38% and 6.12%, respectively.

关键词： Grain refinement Growth mechanism Superalloy Solidification

ANALYSIS OF FIRST TRANSIENT PRESSURE OSCILLATION FOR LEAKDETECTION IN A SINGLE PIPElinE

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Journal of Hydrodynamics 2012年第3期24卷 363-370页

作者： YANG Kai-lin LI fu-tian WANG Tao fu hui State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of WaterResources and Hydropower Research Beijing 100038 China

The leak detection is of great importance in the reliable operation and management of a pipeline system. Recently, attention is shifted to the use of the time domain or frequency domain methods based on the transient analysis. These methods sometimes require accurate pressure signals obtained during the transient period or by creating ideal conditions in testing. This paper proposes a method that does not require transient simulations over the whole or an extended period of time, but uses the first transient pressure oscillation to detect leaks. The method considers the propagation of the pressure oscillation wave created from a fast valve closure and the reflected damp wave from the leak. A leak in the pipe gives rise to reflected waves which in turn create discontinuities in the observed signal at the measurement section. The timing of the reflected damp wave and the magnitude represent the location and the size of the leak, respectively. An analytical expression is derived based on the Method Of Characteristic （MOC） for the relationship between the leakage and the reflected magnitude. The leak detection procedure based on the method is also given. Then the reliability of the method is tested on numerically simulated pressure signals and experimental pressure signals with calibrated leak parameters, and the results indicate a successful application and the promising features of the method.

关键词： leak detection hydraulic transient pressure oscillation pipeline

Hot workability characteristics of Rene88DT superalloy with directionally solidified microstructure

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Rare Metals 2015年第1期34卷 51-63页

作者： fu-lin Li Rui fu Di Feng Zhi-ling Tian Superalloy Department Central Iron & Steel Research Institute

The hot deformation characteristics of Rene88DT superalloy with directionally solidified micro- structure produced by electroslag remelting continuous directionally solidification （ESR-CDS） were studied in the temperature range of 1,040-1,140 ℃ and strain rate range of 0.001-1.000 s-1 by hot compression tests. Flow curves for Rene88DT alloy with initial directionally solidified （DS） microstructure exhibit pronounced peak stresses at the early stage of deformation followed by the occurrence of dynamic softening phenomenon. Rene88DT alloy with DS micro- structure shows higher flow peak stresses compared with HIPed P/M superalloy FGH4096, but the disparities in peak stresses between ESR-CDSed Rene88DT and HIPed P/M superalloy FGH4096 reduce as temperature increases. The improvement of hot workability of DS alloy with columnar grains avoiding the maximum shear stress comes true. A hot deformation constitutive equation as a function of strain that describes the dependence of flow stress on strain rate and temperature is established. Hot deformation apparent acti- vation energy （Q） varies not only with the strain rate and temperature but also with strain. The strain rate sensitivity exponent （m） map is established at the strain of 0.8, which reveals that global dynamic recrystallization （DRX） shows a relatively high m value in a large strain compression. Optimum parameters are predicted in two regions： T = 1,100-1,130 ℃, ε = 0.100-1.000 s-1 and T = 1,080- 1,100 ℃, ε = 0.010-100 s-1, which is based on pro- cessing maps and deformation microstructure observations.

关键词： Rene88DT alloy Directional solidification Isothermal compression Constitutive equation Processingmap

Spatiotemporal variations of ambient air pollutants and meteorological influences over typical urban agglomerations in China during the COVID-19 lockdown

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Journal of Environmental Sciences 2021年第8期33卷 26-38页

作者： linping Fan shuang fu Xin Wang Qingyan fu Haohao Jia Hao Xu Guimei Qin Xue Hu Jinping Cheng School of Environmental Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China China National Environmental Monitoring Center Beijing 100012China Shanghai Environmental Monitor Center Shanghai 200235China

To investigate the air quality change during the COVID-19 pandemic,we analyzed spatiotemporal variations of six criteria pollutants in nine typical urban agglomerations in China using ground-based data and examined meteorological influences through correlation analysis and backward trajectory analysis under different *** of PM2.5,PM10,NO2,SO2 and CO in urban agglomerations respectively decreased by 18%–45%(30%–62%),17%–53%(22%–39%),47%-64%(14%–41%),9%–34%(0%–53%)and 16%-52%(23%–56%)during Lockdown(Post-lockdown)period relative to Pre-lockdown ***2.5 pollution events occurred during Lockdown in Beijing-Tianjin-Hebe(BTH)and Middle and South Liaoning(MSL),and daily O3 concentration rose to gradeⅡstandard in Post-lockdown *** from the nationwide slump of NO2 during Lockdown period,a rebound(~40%)in Post-lockdown period was observed in Cheng-Yu(CY),Yangtze River Middle-Reach(YRMR),Yangtze River Delta(YRD)and Pearl River Delta(PRD).With slightly higher wind speed compared with 2019,the reduction of PM2.5(51%–62%)in Post-lockdown period is more than2019(15%–46%)in HC(Harbin-Changchun),MSL,BTH,CP(Central Plain)and SP(ShandongPeninsula),suggesting lockdown measures are effective to PM2.5 *** O3 concentrations generally increased during the lockdown,its increment rate declined compared with 2019 under similar sunlight duration and ***,unlike HC,MSL and BTH,which suffered from additional(>30%)air masses from surrounding areas after the lockdown,the polluted air masses reaching YRD and PRD mostly originated from the long-distance transport,highlighting the importance of joint regional governance.

关键词： COVID-19 Air pollutants Spatial and temporal variations Urban agglomeration Meteorological condition China

Development and case study of a science-based software platform to support policy making on air quality

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Journal of Environmental Sciences 2015年第1期27卷 97-107页

作者： Yun Zhu Yanwen Lao Carey Jang Chen-Jen lin Jia Xing Shuxiao Wang Joshua S.fu shuang Deng Junping Xie Shicheng Long Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control College of Environmental and Energy South China University of Technology Guangzhou Higher Education Mega Center State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex School of Environment Tsinghua University College of Environmental and Energy South China University of Technology Guangzhou Higher Education Mega Center USEPA/Office of Air Quality Planning & Standards RTPNC 27711 USA Department of Civil Engineering Lamar University Department of Civil & Environmental Engineering University of Tennessee Chinese Research Academy of Environmental Sciences

This article describes the development and implementations of a novel software platform that supports real-time, science-based policy making on air quality through a user-friendly interface. The software, RSM-VAT, uses a response surface modeling（RSM） methodology and serves as a visualization and analysis tool（VAT） for three-dimensional air quality data obtained by atmospheric models. The software features a number of powerful and intuitive data visualization functions for illustrating the complex nonlinear relationship between emission reductions and air quality benefits. The case study of contiguous *** that the enhanced RSM-VAT is capable of reproducing the air quality model results with Normalized Mean Bias 〈 2% and assisting in air quality policy making in near real time.

关键词： Air quality Policy making Response surface modeling Emission control scenarios Data visualization

Improvement in antibacterial ability and cell cytotoxicity of Ti-Cu alloy by anodic oxidation

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Rare Metals 2022年第2期41卷 594-609页

作者： shuang Cao Zi-Ming Zhang Jia-Qi Zhang Ren-Xian Wang Xiao-Yan Wang Lei Yang Da-fu Chen Gao-Wu Qin Er-lin Zhang School of Materials Science and Engineering Key Laboratory for Anisotropy and Texture of MaterialsEducation Ministry of ChinaNortheastern UniversityShenyang 110819China Departments of Immunology College of Basic MedicineJiamusi UniversityJiamusi 154007China Laboratory of Bone Tissue Engineering Beijing Laboratory of Biomedical MaterialsBeijing Research Institute of Orthopaedics and TraumatologyBeijing Jishuitan HospitalBeijing 100035China School of Metallurgy Northeastern UniversityShenyang 110819China Research Center for Metallic Wires Northeastern UniversityShenyang 110819China

Ti-Cu alloy has potential to be used in plastic surgery and dental implants due to its strong antibacterialproperties,high strength and good corrosion *** this paper,Ti-5Cu was anodic-oxidized to enhance the surface *** influence of the oxidation on the corrosion resistance,antibacterial properties and biological properties was investigated.X-ray diffraction(XRD)and X-ray photoelectron spectroscopy(XPS)results showed that a double-layer oxide coating with dense inner layer and porous outside layer was formed on Ti-Cu *** oxide coating consisted mainly of TiO2,CuzO and small amount of CuO,improved the corrosion resistance of Ti-Cu alloy by one order of magnitude due to the formation of the dense oxide inner layer,but high Cu ion release was *** plate count results showed that the antibac-terial activity of Ti-Cu sample was improved to≥99%due to the comprehensive function of CuO and Cu_(2)O in the coating and Cu^(2+)*** test results showed that thecoating exhibited good cell compatibility,the porous sur-face structure improved the adhesion of cells,and Cu ion release promoted the cell proliferation.

关键词： Titanium-copper alloy Anodic oxidation Corrosion resistance Antibacterial activity Cell adhesion Surface modification

Intermediate symmetric construction of transformation between anyon and Gentile statistics

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Communications in Theoretical Physics 2021年第6期73卷 126-130页

作者： Yao Shen fu-lin Zhang School of Criminal Investigation People's Public Security University of ChinaBeijing 100038China Department of Physics School of ScienceTianjin UniversityTianjin 300072China

Gentile statistics describes fractional statistical systems in the occupation number *** statistics researches those systems in the winding number *** of them are intermediate statistics between Bose–Einstein and Fermi–Dirac *** second quantization of Gentile statistics shows a lot of *** to the symmetry requirement of the wave function and the property of braiding,we give the general construction of transformation between anyon and Gentile *** other words,we introduce the second quantization form of anyons in an easier *** construction is a correspondence between two fractional statistics and gives a new description of *** relations of second quantization operators,the coherent state and Berry phase are also discussed.

关键词： gentile statistics anyon fractional statistics computational method

Millimeter observations of organic molecules toward high-mass star formation region G34.26+0.15

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Research in Astronomy and Astrophysics 2016年第12期16卷 34-40页

作者： Li fu Guo-Man lin School of Chemistry & Material Science Langfang Teachers University College of Chemistry & Molecular Engineering Peking University School of Physics & Electronics Langfang Teachers University

To investigate the chemical origination of organic molecules CH3OH, CH3OCH3, C2H5OH, CH3OCH, CH3CN, C2HaCN and C2H5CN in the hot core associated with high-mass star formation re- gion G34.26＋0.15, Submillimeter Array observations were made with its 230 GHz receiver. The molecular gas distribution has shown that the oxygen- and nitrogen-containing molecules peak at different positions. Comparing the spatial distributions with rotational temperatures and fractional abundances of the observed molecules, we discuss the possible chemical origination of these organic molecules.

关键词： astrochemistry -- molecular processes -- line: identification -- ISM: abundances