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Diagnostic and surgical therapeutic features of extrahepatic bile duct carcinoma without jaundice

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World Journal of Gastroenterology 2004年第20期10卷 3060-3061页

作者： hui-HuanTang ShiChang xian-WeiWang YunHuang Xue-JunGong JunZhou DepartmentofSurgery XiangyaHospitalofCentralSouthUniversityChangsha410008HunanProvinceChina

AIM: To analyze the diagnostic and therapeutic features of extrahepatic bile duct carcinoma (EBDC) without jaundice. METHODS: Between 1985 and 1999, 101 patients underwent surgery for EBDC in xiangya Hospital. These patients were divided into two groups: 84 jaundiced patients and 17 nonjaundiced patients according to preoperative serum total bilirubin levels. The dinical manifestations, laboratory findings, location, pathology and surgical resectability of the tumors were compared between the two groups. RESULTS: The laboratory parameters such as hemoglobin,serum albumin ALB, AKP, γ-GT, and sonography appearancewere similar between the two groups, and there was no significant difference in tumor location, pathological type and resectability. However, the number of non-jaundiced patients associated with chololithiasis was significantly greater than that of jaundiced patients (P=0.008). CONCLUSION: The presence of jaundice is not a reliable criterion for the prediction of the resectability and the extent of tumor progression in extrahepatic bile duct carcinoma. Decreased levels of blood hemoglobin and serum albumin, elevated levels of AKP and γ-GT, and/or abnormal sonography may be suggestive. Biopsy of a stenotic or thickened bile duct is strongly recommended for a correct diagnosis before the appearance of jaundice.

关键词：诊断外科治疗肝外胆管胆汁排泄管癌症黄疸肿瘤

Modulating conductivity type of cuprous oxide（Cu2O） films on copper foil in aqueous solution by comproportionation

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Journal of Materials Science & Technology 2019年第8期35卷 1570-1577页

作者： Changwei Tang Xiaohui ning Jian Li hui-Lin Guo Ying Yang Shaanxi Provincial Key Laboratory of Electroanalytical Chemistry Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of the Ministry of EducationCollege of Chemistry & Materials ScienceNorthwest UniversityXi'an 710127 China National Demonstration Center for Experimental Chemistry Education Northwest UniversityXi'an 710127 China International Research Center for Renewable Energy State Key Laboratory of Multiphase Flow in Power EngineeringXi'an Jiaotong UniversityXi'an 710049 China

Cuprous oxide(Cu2O)is an attractive material for photoelectrochemical(PEC)hydrogen production or photovoltaic application,because of its appropriate band gap,low material cost and *** this paper,Cu2O films were obtained by comproportionation in acid cupric sulfate solutions with varying concentrations of potassium *** and electrochemical experiments,such as zero-bias photocurrent responses,voltammograms,and Mott-Schottky measurements,show that the Cu2O films grown in low(≤0.75 mol dm^–3)and high(≥1.00 mol dm^–3)nitrate ion concentrations presented n-type and p-type conductivity,*** circuit potential and polarization behavior were monitored to investigate the mechanism of modulating conductivity *** ions consume protons in the plating solution during comproportionation with different concentrations of nitrate ions creating different pH at the Cu2O/solution *** gradient leads to the transformation of Cu2Ofilms conductivity changing from n-type to p-type with increasing the concentration of nitrate ions in the plating *** method could be used to fabricate homojunction electrode on metal substrate for PEC hydrogen production or photoelectric application.

关键词： Cuprous oxide(Cu2O) Comproportionation Semiconductor films Tuning conductivity Photoelectrochemical cell

Microstructure and Dynamic Compression Properties of PM Al6061/B_4C Composite

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Acta Metallurgica Sinica(English Letters) 2015年第10期28卷 1214-1221页

作者： Hong-Sheng Chen Wen-xian Wang hui-hui Nie Yu-Li Li Qiao-Chu Wu Peng Zhang College of Materials Science and Engineering Taiyuan University of Technology Key Laboratory of Interface Science and Engineering in Advanced Materials Ministry of Education Taiyuan University of Technology Shanxi Key Laboratory of Advanced Magnesium-Based Materials Taiyuan University of Technology

Aluminum 6061 matrix composite reinforced by 35 wt% B4 C particle was fabricated by power metallurgy method. Then, the as-deformed composite was tested by quasi-static（0.001 s-1） and dynamic（760-1150 s-1） compression experiments. The Johnson-Cook plasticity model was employed to model the flow behavior. The damage mechanism of composite was analyzed through the microstructure observations. The results showed that the B4 C particles exhibited uniform distribution and no deleterious reaction product Al4C3 was found in the composite. Al6061/B4 C composite showed high yield strength, moderate strain rate sensitivity and strain hardening under the dynamic loading, and a constitutive model under dynamic compression was established based on Johnson-Cook model, and accorded well with experimental results. The microstructure damage was dominated by particle fracture and interface debonding, and the dislocation was observed in the composite at a higher strain rate.

关键词： Power metallurgy Dynamic compression Johnson-Cook model AI6061/B4C composite

Hydrodynamic performance of flexible risers subject to vortex-induced vibrations

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Journal of Hydrodynamics 2013年第1期25卷 156-164页

作者： ZHANG hui YANG Jian-min XIAO Long-fei LU Hai-ning State Key Laboratory of Ocean Engineering Shanghai Jiaotong University

The Vortex-Induced Vibration （VIV） displacements are determined from both the measured accelerations and strains in a series of VIV experiments. Based on the results, the forces in the longitudinal, transversal and tangential directions are estimated by using the finite element method with and without considering the interactions between adjacent elements. The numerical simulation indicates that the method considering the interactions performs better in the estimation of the forces. The component of the transversal force in phase with the acceleration is associated with the added mass coefficient. The estimated added mass coefficients take abnormally high values at the locations where the displacements are small. An improved formula based on the L＇Hospital＇s rule is pro- posed to deal with this problem. The results show the advantage of this formula in estimating the added mass coefficients at the loca- tions with small VIV displacements.

关键词： Vortex-Induced Vibration (VIV) flexible risers hydrodynamic force added mass coefficient

Selective interfacial bonding and thermal conductivity of diamond/Cu-alloy composites prepared by HPHT technique

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International Journal of Minerals,Metallurgy and Materials 2012年第4期19卷 364-371页

作者： hui Chen Cheng-chang Jia Shang-jie Li xian Jia Xia Yang School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China Shenzhen Haimingrun Industrial Co. Ltd. Shenzhen 518126 China

Cu-based and Cu-alloy-based diamond composites were made by high-pressure-high-temperature （HPHT） sintering with the aim of maximizing the thermal conductivity of the composites. Improvements in interfacial bonding strength and thermo-physical properties of the composites were achieved using an atomized copper alloy with minor additions of Co, Cr, 13, and Ti. The thermal conductivity （TC） oh- mined exhibited as high as 688 W.m-1.K-1, but also as low as 325 W.m-1.K-l. A large variation in TC can be rationalized by the discrepancy of diamond-matrix interfacial bonding. It was found from fractography that preferential bonding between diamond and the Cu-alloy matrix occurred only on the diamond {100} faces. EDS analysis and Raman spectra suggested that selective interfacial bonding may be attributed to amorphous carbon increasing the wettability between diamond and the Cu-alloy matrix. Amorphous carbon was found to significantly affect the TC of the composite by interface modification.

关键词： metallic matrix composites diamonds copper alloys interfacial bonding thermal conductivity

Constructing mild expanded graphite microspheres by pressurized oxidation combined microwave treatment for enhanced lithium storage

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Rare Metals 2021年第4期40卷 837-847页

作者： Can-Liang Ma Zhen-hui Hu ning-Jing Song Yun Zhao Yan-Zhen Liu hui-Qi Wang Key Laboratory of Materials for Energy Conversion and Storage of Shanxi Province Institute of Molecular ScienceShanxi UniversityTaiyuan 030006China College of Chemistry and Chemical Engineering Jinzhong UniversityJinzhong 030619China CAS Key Laboratory of Carbon Materials Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001China School of Energy and Power Engineering School of Material Science and EngineeringNorth University of ChinaTaiyuan 030051China

The modified graphite anode materials have some prominent advantages over other anode materials in the industrial applications.A novel simple and gentle method is proposed to synthesize the mild expanded graphite microspheres(MEGMs) from flake graphite spheres through a combined modified pressurized oxidation combined with the microwave *** microstructural results demonstrate that moderately expanded MEGMs with an expansion volume between 4 and 10 ml·g^(-1)exhibit a highly microporous structure with an enlarged interlayer spacing,a decreased microcrystalline size,as well as an increased number of functional groups on the surface,resulting in the increased storage sites and spaces for lithium ions and the enhanced diffusion rate of lithium *** used as the anode material for lithium-ion batteries,the MEGM-T75t30 obtained by oxidation treatment at 75℃ for 30 min followed by microwave irradiation for expansion displays a high reversible capacity of 446.7 mAh·g^(-1) at 100 mA·g^(-1) after 100 cycles and excellent rate performance(330 and 116 mAh·g^(-1) at 800 and 3200 mA·g^(-1),respectively).Therefore,the MEGMs prepared by this convenient and mild method show excellent electrochemical properties and good application potential.

关键词： Pressurized oxidation Microwave treatment Mild expanded graphite microspheres Microstructure Graphitic anode material Lithium-ion battery

Effects of dissolved organic matter from sewage sludge on sorption of tetrabromobisphenol A by soils

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Journal of Environmental Sciences 2008年第9期20卷 1075-1081页

作者： SUN Zhaohai MAO Li xian Qiming YU Yijun LI hui YU Hongxia State Key Laboratory of Pollution Control and Resource Reuse School of the Environment Nanjing University Nanjing 210093 China Department of Crop and Soil Sciences Michigan State University East Lansing 48824 USA

Sorption of tetrabromobisphenol A (TBBPA) by soil influences its fate and transport in the environment. The presence of dissolved organic matter (DOM) may complicate the sorption process in soil. The effects of DOM from sewage sludge on TBBPA sorption by three soils were investigated using batch equilibration experiments in the study. DOM was observed to be sorbed on the soils and the isotherms could be fitted by the Langmuir model. The effects of DOM on TBBPA sorption were dependent on the characteristics ...

关键词： tetrabromobisphenol A (TBBPA) sorption dissolved organic matter pH soil sewage sludge

Texture development of mesophase in reservoir pyrobitumen and the temperature-pressure converting of the gas reservoir in the Chuanzhong Uplift, Southwestern China

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Petroleum Science 2023年第2期20卷 721-732页

作者： Cheng-Yu Yang Mei-Jun Li Tie-Guan Wang ning-ning Zhong Rong-hui Fang Long Wen State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing102249China Oil&Gas Survey China Geological SurveyBeijing100083China The Key Laboratory of Unconventional Petroleum Geology China Geological SurveyBeijing100083China Exploration and Development Research Institute of Southwest Oil&Gasfield Company PetroChinaChengduSichuan610041China

The Neoproterozoic-Lower Paleozoic dolostone gas reservoirs in the Chuanzhong Uplift in Southwestern China contain the mesophase pyrobitumen (pyrobitumen with mesophase). The mesophase in the pyrobitumen is mostly composed of a mixture of condensed macromolecule polycyclic aromatic hydrocarbons (PAH), and has been mostly converted to various grain, flow, and domain textures. The volcanic activity nearby the Chuanzhong Uplift may have generated very hot (over 300 °C) hydrothermal fluid, with migration of the fluid into the dolostone reservoir transforming the hydrocarbons in the reservoir into an anisotropic carbon by-product, which formed under high temperature and pressure conditions;over 300 °C and 200 MPa according to fluid inclusion analysis. The high temperature-pressure in reservoir was caused by sudden devolatilization of the hydrocarbons due to hydrothermal heating, which formed the unusual texture of the mesophase. The elliptical mesophase grains (EG), the honeycomb structure of pyrobitumen, and the occurrence of polarized classes of mesophase in single pyrobitumen deposits are all unusual textures. This study investigates the texture development of this pressure-affected pyrobitumen. Observation and study of the mesophase suggest that the class of mesophase in pyrobitumen is determined by temperature, while pressure (assessed from associated fluid inclusions) significantly affected the texture. Analysis of the texture of the pyrobitumen in conjunction with previous thermometry results from methane inclusions suggests that the high class mesophase of the pyrobitumen could be applied as a temperature indicator for geological conditions. Furthermore, the unusual textures of the pyrobitumen including elliptical mesophase grains (EG), the honeycomb structure of pyrobitumen, and the occurrence of polarized classes of mesophase in single pyrobitumen could reflect the abnormal high formation pressure.

关键词： Pyrobitumen Mesophase Optical texture Pressure affect Oil reservoir Chuanzhong Uplift

Gigacycle fatigue behaviors of two SNCM439 steels with different tensile strengthes

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Acta Mechanica Sinica 2011年第5期27卷 778-784页

作者： Zheng Duan xian-Feng Ma hui-Ji Shi Ryosuke Murai Eiichi Yanagisawa AML DepartmentofEngineeringMechanicsSchoolofAerospaceTsinghuaUniversity100084BeijingChinaAML Department of Engineering MechanicsSchool of Aerospace Tsinghua University100084 Beijing China Mitsubishi Heavy Industries Ltd. Tokyo Japan

Gigacycle fatigue behaviors of two SNCM439 steels with different tensile strengthes were experimentally studied by rotating bending tests,to investigate the effects of the tensile strength obtained by different heat treatment processes on very high cycle fatigue failure *** material with higher tensile strength of 1 710 MPa exhibited typical gigacycle fatigue failure characteristics,whereas one with lower tensile strength of 1 010 MPa showed only traditional fatigue limit during the tests and no gigacycle failure could be found even when the specimen ran up to more than 10 8 *** and fractographic analysis were carried out by an optical microscope （OM） and scanning electron microscope （SEM）.It showed two different crack initiation mechanisms that for the specimen with lower tensile strength the crack prefers surface initiation and for that with higher strength the crack initiates from subsurface inclusions revealed by a fish-eye like microstructure.

关键词： Gigacycle fatigue · S-N curves · Crack initiation · Fractography