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Two-dimensional numerical algorithm for water quality modeling in the topographically complicated river

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Journal of Environmental Sciences 2000年第4期12卷 469-473页

作者： Zeng, G. Jiang, Y. guo, h. huang, G.G.-h. Environmental Protection Institute Human University Hunan 410082 China

In this paper, a two-dimensional numerical calculation algorithm for the water quality modeling in the hengyang City section of the Xiangjiang River is researched considering the effect of the Dayuandu navigational key project. The research river is winding and has two branches resulted from an isle. The numerical calculation algorithm for the water quality modeling is set up on the basis of applying topographic map of the river course and the finite element method. The calculation result for the water quality modeling includes the concentration fields for various pollutants. The numerical calculation algorithm for the water quality modeling set up in this paper can be applied to shallow river with similar topographically complicated river course.

关键词： Algorithms Finite element method River pollution Rivers

Diameter-dependent in vitro performance of biodegradable pure zinc wires for suture application

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Journal of Materials Science & Technology 2019年第8期35卷 1662-1670页

作者： h. guo R.h. Cao Y.F. Zheng J. Bai F. Xue C.L. Chu State Key Laboratory for Turbulence and Complex System and Department of Materials Science and Engineering College of Engineering Peking University Beijing 100871 China School of Materials Science and Engineering Southeast University Nanjing 211189 China Key Laboratory for Advanced Metallic Materials Southeast University Nanjing 211189 China

In this study, biodegradable pure zinc wires with 3.0 mm and 0.3 mm in diameter were prepared via hot-extrusion and subsequent cold-drawing process respectively. The microstructure, mechanical performance, corrosion behavior, in vitro cytocompatibility and antibacterial effect were comparatively *** cold-drawing, the mechanical property, especially the elongation of the ф0.3 mm pure Zn wire was improved significantly compared with the ф3.0 mm pure Zn wire. The in vitro corrosion study including immersion and electrochemical test showed acceptable corrosion resistance of these two materials in hank's solution. The in vitro human Umbilical Vein Endothelial Cells(hUVECs) viability assay showed obviously different results, in which the ф0.3 mm pure Zn wire demonstrated favorable cytocompatibility, while the ф3.0 mm wire exhibited severe cytotoxic effect with 100% extract concentration. Both of them exhibited partly antibacterial effect on S. aureus. These results demonstrated the feasibility of the prepared 0.3 mm pure Zn wire as the potential suture material with good absorbability.

关键词： Pure zinc Wire Biodegradable metal Suture

MICROSTRUCTURE AND MEChANICAL PROPERTIES OF Mg-Li ALLOY WITh Ca ADDITION

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Acta Metallurgica Sinica(English Letters) 2006年第5期19卷 355-361页

作者： h.B. Li G. C. Yao Z.Q. guo Y.h. Liu h.J. Yu h.B. Ji School of Materials ＆ Metallurgy Northeastern University Shenyang 110004 China

Mg-9wt%Li-2wt%Zn alloy was prepared and studied in this article. The addition of Ca to the alloy from 0.1wt% to 1wt% can refine the α-Mg and the best effect of refinement occurs when Ca content is 0.4wt%-0.5wt%. The billets can be rolled to thin sheets at room temperature, from which it is obvious that the addition of Ca improves alloys ormalin. while it decreases with the excess addition of Ca. The results also show that the ultimate tensile strength （UTS） and yield strength （YS） of the alloy with lwt% Ca may rise by 28% and 25%, respectively, however, the elongation decreases. It is clarified that the adsorption of proper Ca on the grain boundaries refines α-Mg and improves the tensile properties, but the presence of excess Ca and stable Ca2Mg6Zn3phase worsens the elongation.

关键词： calcium Mg-Li-Zn alloy cold rolling microstructure tensile property

A Quantitative Analysis of Mn Segregation at Partitioned Ferrite/Austenite Interface in a Fe-C-Mn-Si Alloy

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Journal of Materials Science & Technology 2009年第3期25卷 383-388页

作者： h. guo S.W. Yang C.J.Shang X.M. Wang X.L. he Department of Materials Physics and Chemistry University of Science and Technology Beijing Beijing 100083 China

Mn segregation at austenite/ferrite interface is studied in a Fe-C-Mn-Si alloy held at 656℃. Mn is partitioned during the growth of ferrite and as a result, a Mn pile-up exists in front of interface on the matrix side. An approach to evaluate Mn segregation quantitatively is developed by combining STEM raster window scanning and simulation of the interaction of the electron beam with the sample to subtract the contribution of Mn pile-up and obtain pure Mn segregation value. The evaluated maximum Mn interfacial segregation is in the order of a half-monolayer.

关键词： Interfacial segregation Phase transformation STEM Beam broadening

CREVICE CORROSION BEhAVIOR OF X70 STEEL IN hCO_3^- SOLUTION UNDER CAThODIC POLARIZATION

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Acta Metallurgica Sinica(English Letters) 2008年第4期21卷 235-244页

作者： C.W. Du X.G. Li X. Chen P. Liang h. guo School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China Liaoning University of Petroleum and Chemical Technology ~shun 113001 China

The crevice corrosion behavior of XTO steel was investigated with a wedge-shaped crevice assembly under -1000 m V （SCE） cathodic polarization in the solutions with various hCO3 concentrations. The potential, current, ph and the oxygen content within the crevice were measured with or without outside coupled specimen. The results indicated that the polarization potential of XTO steel in the crevice dropped with the increase of time under the cathodic polarization. There was a remarkable influence of hCO3 concentration on the potential of XTO steel in the crevice. When hCO3 concentration was up to 0.125%, the surface of the metal was covered with the corrosion products that resulted in the polarization extent of XTO steel decreased. The ph value in the crevice rose and it dropped gradually from the crevice mouth to the bottom under the cathodic polarization. With the increasing of hCO3 concentration, the hydrolyzation reaction of metal in the crevice bottom aggravated. Most of the dissolved oxygen in the crevice was consumed by the cathodic current. The maximum cathodic current on the metal surface was at the crevice mouth and it was much more than that at the crevice bottom.

关键词： Cathodic polarization XTO steel Potential ph value Oxygen

FEM ANALYSIS OF ThERMAL STRESSES IN GRADIENT ThERMAL BARRIER COATINGS PRODUCED BY EB-PVD

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Acta Metallurgica Sinica(English Letters) 2001年第6期14卷 493-496页

作者： h.B. guo, h.B. Xu and S.K. Gong (Department of Materials Science & Engineering, Beijing University of Aeronautics and Astronautics, Beijing 100083, China) Dept. of Mat. Sci. and Eng. Beijing Univ. of Aero. and Astron. Beijing 100083 China

Gradient thermal barrier coatings (GTBCs) produced by co-deposition of mixtures ofAl-Al2 O3-YSZ onto metallic bond coat exhibited longer lifetimes than the two-layeredTBCs. The finite element method (FEM) numerical models were used to investigatestress and strain states in the GTBCs and traditional two-layered TBCs as they cooledto 750℃ from a stress-free state at 850℃.

关键词： EB-PVD gradient thermal barrier coating finite element method

Mode and Bond Selectivity in Bimolecular Reactions: Extension of Polanyi’s Rules

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Mode and Bond Selectivity in Bimolecular Reactions: Extensio...

Comparison of body weight and food consumption in young adult SD rats

第十三届全国化学动力学会议

作者： h.guo Department of Chemistry and Chemical Biology University of New Mexico

＜正＞It is well established that different forms of energy have different efficacies in promoting an activated bimolecular reaction in the gas phase. Based on both experimental and theoretical evidence of the time, Polanyi’s proposed a set of rules to determine the relative efficacies of vibrational vs. translational energy

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Comparison of body weight and food consumption in young adul...

Comparison of body weight and food consumption in young adult SD rats

2013年（第三届）中国药物毒理学年会暨药物非临床安全性评价研究论坛

作者： guo h Sue McPhERSON Steve MASON WuXi AppTec Co.Ltd.

An meta-analysis was performed for control animals from over 25 toxicology studies to assess potential differences in body weight gain and food consumption between Sprague-Dawley rats sourced from commercial suppliers in the USA(Charles River-"CR"),***(Vital River-"VR") and Taiwan(BioLasco-"BL").The mean body weight and food consumption was calculated weekly for animals in the age range 6 to 35 *** to approximately 15 weeks of age,CR males were generally lighter than BL males,after this time the growth rate of the CR males appeared to exceed that of those from BL.A similar pattern was seen for female rats with the CR animals exhibiting lower body weight than BL rats before approximately 11 weeks of *** age 11 weeks the CR rats were heavier than BL *** VR animals, initial growth was similar to CR rats,and followed closer to the BL growth rate from approximately week *** general, the CR male and female SD rats grew faster than those from either BL or *** the male rats there were no clear differences in food consumption between CR and BL animals,in comparison food consumption for the VR rats was a little lower. For the females,CR rats tended to show a higher food intake than both BL and VR,with the food for consumption from animals from the latter two sources being generally *** observed differences between the three sources of animals demonstrate the need to be consistent in the source of animals for different studies in toxicology development programs with a single compound,and also the need for maintaining separate back ground data bases.

关键词： body mass food consumption

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Comparison of body weight and food consumption in young adul...