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Association between thrombotic risk factors and extent of fibrosis in patients with non-alcoholic fatty liver diseases

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World Journal of Gastroenterology 2005年第37期11卷 5834-5839页

作者： n Assy I Bekirov y Mejritsky L Solomon S Szvalb O Hussein Liver Unit and Internal Medicine A Sieff Hospital Safed Israel Technion Faculty of Medicine Haifa Israel Liver Unit and Internal Medicine B Sieff Hospital Safed Israel Department of HematologySieff Hospital SafedIsrael Department of PathologySieff Hospital Safed Israel

AIM: To evaluate the prevalence of genetic and acquired prothrombotic risk factors and their association with the extent of fibrosis and fatty infiltration in patients with non-alcoholic fatty liver disease (nAFLD).METHODS: Forty-four patients with chronic hepatitis (28 men and 16 women, with mean age of 45±11 and 49±12 years, respectively) constituted the patient population of this study. The groups were divided as follows: 15 patients with fatty liver (FL); 15 with non-alcoholic steatohepatitis (nASH); 14 with chronic viral hepatitis (CH) diagnosed by histology and liver technetium scan or ultrasound; and 10 healthy individuals. Thrombophilic, coagulation factors and genetic mutations were diagnosed by standard hemostatic and molecular coagulation ***: Activated protein C (APC) resistance and protein S were the most prevalent thrombotic risk factors (6% and 10% in nAFLD vs 21% and 14% in CH; P＜0.01 and P＜0.05, respectively). One thrombotic risk factor was identified in 41% of patients (23% mild fibrosis, 18% severe fibrosis) and two thrombotic risk factors in 6% of patients with nAFLD and severe fibrosis. While no differences in APC ratio, lupus anticoagulant, fibrinogen, factor V Leiden,prothrombin, and MTHFR mutation were found. Protein S levels were significantly lower in nASH patients than in patients with FL alone (92±19 vs106±2, P＜0.01). Protein C levels were markedly higher in patients with nAFLD and mild or severe fibrosis as compared to the patients with CH, respectively (128±40 vs96±14, P＜0.001 or 129±36 vs 88±13, P＜0.01).COnCLUSIOn: Up to 46% of patients with nAFLD may have thrombotic risk factors, and the presence of thrombotic risk factors is correlated with the extent of hepatic fibrosis,suggesting a crucial role of the coagulation system in the pathogenesis of hepatic fibrosis.

关键词： nASH nAFLD Thrombotic risk factors Fibrosis Protein S Protein C

Electrochemical Reaction Processes of niobium Ions in FLInAK melt

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International Journal of Minerals,Metallurgy and Materials 1999年第2期13卷 83-89页

作者： Wang, Xindong Duan, Shuzhen Christensen, E. Bjerrum, n.J. Ito, y. Metallurgy School University of Science and Technology Beijing Beijing 100083 China Materials Science Group Chemistry Department A Technical University of Denmark DK-2800 Lyngby Denmark Department of Energy Science and Engineering Kyoto University Kyoto 606 Japan

ThecathodicProcessmechanismofniobiumreductionfromchloride-fluorideandfiuoridemeltshasbeenstudiedindetail[l-],batth***,threehoesofmodelshaVebeenPutforwardtoexplaintheelectrochemic... 详细信息

ThecathodicProcessmechanismofniobiumreductionfromchloride-fluorideandfiuoridemeltshasbeenstudiedindetail[l-],batth***,threehoesofmodelshaVebeenPutforwardtoexplaintheelectrochemic...

关键词： electrochemistry molten Salt FLInAK niobium reduction

Magnetic transitions and butterfly-shaped hysteresis of Sm-Fe-Al-based perovskite-type orthoferrite

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Journal of Rare Earths 2015年第9期33卷 965-971页

作者： M.A.Ahmed n.G.Imam M.K.Abdelmaksoud y.A.Saeid Materials Science Lab. Physics Department Faculty of Science Cairo University Materials Science Lab. Experimental Physics Department Nuclear Research Center Atomic Energy Authority

A1 doped SmFeO3 （SmFel_xmlxO3; 0.0〈x〈0.15; step 0.05） were prepared by double sintering ceramic technique. The obtained samples were crystallized in single phase structure except the sample with x=0.15. The unit cell volume was found to decrease with increasing AI substitution in orthoferrite. The effective magnetic moment （μeff） and the Curie constant （C） were calculated from the reciprocal of the molar magnetic susceptibility （Z-1） versus absolute temperature plot and found to attain maximum value for the parent sample. The magnetic behavior showed two different magnetic transitions, viz, n6el temperature （Tn） and spin reorientation （TsR） transitions. The M-H hysteresis loop of the parent sample took butterfly-shape as a result of different contributions anisotropies. From the magnetic properties measurements, it was obviously found that B-site cation dilution resulted in a drastic decrease in the magnetization. Surprisingly large value of the coercive field was obtained for the undoped sample;Hc=6198.80e. Based on the mentioned results, one can recommend the use of such orthoferrite in magnetic recording media and as pining layer in spin valve for spin- tronic applications.

关键词： SmFeO3 magnetization FESEM crystal structure spintronics spin reorientation butterfly-shaped hysteresis anisotropy rare earths

Corrosion behavior of hypereutectic Al-23%Si alloy (AC9A) processed by severe plastic deformation

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Transactions of nonferrous Metals Society of China 2010年第2期20卷 195-200页

作者：江静华马爱斌宋丹 n. SAITO 袁玉春 y. nISHIDA College of Materials Science and Engineering Hohai University Nanjing 210098 China national Institute of Advanced Industrial Science and Technology 2266-98 Anagahora Shimoshidami Moriyama-ku Nagoya 463-8560 Japan

Ultrafine-grained(UFG) hypereutectic Al-23%Si (mass fraction) alloy was achieved through equal-channel angular pressing(EACP) procedure. And the electrochemical properties after various ECAP passes were investigated in neutral naCl solution. Potentiostatic polarization curves show that the corrosion potential of the ECAPed sample after 4 passes decreases markedly, while the corrosion current density reaches 1.37 times that of the as-cast alloy. However, the φcorr and Jcorr values after 16 passes are improved and approach those of the as-cast alloy. Immersion tests also show that the mass-loss ratio of ECAPed alloy decreases with increasing the pressing pass, which is lowered to 28.7% with the increase of pass number from 4 to 16. Pitting susceptibility of the ECAPed alloy after initial 4 passes is boosted, due to the presence of biggish voids resulted from the breakage of brittle large primary silicon crystals during ECAP. Increasing ECAP pass makes the voids evanesce and results in the homogeneous ultrafine-grained structure, contributing to a higher pitting resistance. These results indicate that enough ECAP passes are beneficial to increasing corrosion resistance of the hypereutectic Al-23%Si alloy.

关键词： aluminum casting alloys ECAP corrosion behavior ultrafine grained microstructure

Material selection of polymeric composite automotive bumper beam using analytical hierarchy process

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Journal of Central South University 2010年第2期17卷 244-256页

作者： A.HAMBALI S.M.SAPUAn n.ISMAIL y.nUKMAn Department of Mechanical and Manufacturing Engineering Universiti Putra Malaysia Department of Engineering Design and Manufacture University of Malaya

Selection of materials,as an area of design research,has been under considerable interest over the *** selection is one of the most important activities in the product development *** decision of materials can cause the product to be reproduced or *** avoid this circumstance,one of the useful tools that can be employed in determining the most appropriate material is analytical hierarchy process(AHP).To illustrate the application of AHP,six different types of composite materials were *** most appropriate one for suitability of use in manufacturing automotive bumper beam was determined by considering eight main selection factors and 12 *** AHP analysis reveals that the glass fibre epoxy is the most appropriate material because it has the highest value(25.7%,mass fraction) compared with other *** final material is obtained by performing six different scenarios of the sensitivity *** is proved that glass fibre epoxy is the most optimum decision.

关键词： composite polymer matrix bumper beam analytical hierarchy process

Effect of ni Content on Mechanical Properties and Corrosion Behavior of Al/Sn－9Zn－xni/Cu Joints

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Journal of Materials Science & Technology 2012年第9期28卷 844-852页

作者： M.L.Huang n.Kang Q.Zhou y.Z.Huang Key Laboratory of Liaoning Advanced Welding and Joining Technology School of Materials Science&EngineeringDMian University of TechnologyDalian 116024China

The effects of ni content on the microstructure and the wetting behavior of Sn-9Zn-xni solders on Al and Cu substrates, as well as the mechanical properties and electrochemical corrosion behavior of Al/Sn-9Zn-xni/Cu solder joints, were investigated. The microstructure of Sn-gZn-xni revealed that tiny Zn and coarsened ni5Zn21 phases dispersed in theβ-Sn matrix. The wettability of Sn-9Zn-xni solders on Al substrate was much better than that on Cu substrate. With increasing ni content, the wettability on Cu substrate was slightly improved but became worse on Al substrate. In the Al/Sn-9Zn-xni/Cu joints, an Al4.2Cu3.2Zn0.7 intermetallic compound （IMC） layer formed at the Sn-gZn-xni/Cu interfaces, while an Al-Zn-Sn solid solution layer formed at the Sn-9Zn-xni/Al interface. The mixed compounds of ni3Sna and Al3ni dispersed in the solder matrix and coarsened with increasing ni content, thus leading to a reduction in shear strength of the Al/Sn-9Zn- xni/Cu joints. Al particles were segregated at both interfaces in the solder joints. The corrosion potentials of Sn-9Zn-xni solders continuously increased with increasing ni content. The Al/Sn-9Zn-0.25ni/Cu joint was found to have the best electrochemical corrosion resistance in 5% naCl solution.

关键词： Al-Cu disslmilar-metal solder joint Sn-9Zn-xni Microstructure Mechanicalproperties Electrochemical corrosion Corrosion potential

High-temperature thermodynamics of silver:Semi-empirical approach

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Chinese Physics B 2017年第11期26卷 400-407页

作者： R H Joshi B y Thakore P R Vyas A R Jani n K Bhatt Department of Physics Sardar Patel University Department of Physics School of Sciences Gujarat University Sardar Patel Center for Science and Technology Department of Physics M.K.Bhavnagar University

We report high-temperature thermodynamics for fcc silver by combining ab initio phonon dynamics to empirical quadratic temperature-dependent term for anharmonic part of Helmholtz free energy. The electronic free energy is added through an interpolation scheme, which connects ambient condition free electron gas model to Thomas-Fermi *** present study shows good agreement with experimental and reported findings for several thermal properties, and the discrepancy observed in some caloric properties is addressed. The decreases in the product of volume thermal expansion coefficient and isothermal bulk modulus and in the constant volume anharmonic lattice specific heat at high temperature are the clear evidences of proper account of anharmonicity. The present study also reveals that T-2-dependent anharmonic free energy is sufficient for correct evaluation of thermal pressure and conventional Grüneisen parameter. We observe that the intrinsic phonon anharmonicity starts dominating above characteristic temperature, which is attributed to higher order anharmonicity and can be related to higher order potential derivatives. We conclude that the uncorrelated and largeamplitude lattice vibrations at high temperature raise dominating intrinsic thermal stress mechanism, which surpasses the phonon-anharmonism and requires future consideration.

关键词： thermodynamics anharmonicity Grüneisen parameter silver

Effect of electric boundary conditions on crack propagation in ferroelectric ceramics

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Acta Mechanica Sinica 2014年第2期30卷 153-160页

作者： F.-X. Li y.Sun R.K.n.D.Rajapakse State Key Laboratory for Turbulence and Complex Systems College of EngineeringPeking University Faculty of Applied Sciences Simon Fraser University

In this paper, the effect of electric boundary conditions on Mode I crack propagation in ferroelectric ceramics is studied by using both linear and nonlinear piezoelectric fracture mechanics. In linear analysis, impermeable cracks under open circuit and short circuit are analyzed using the Stroh formalism and a rescaling method. It is shown that the energy release rate in short circuit is larger than that in open circuit. In nonlinear analysis, permeable crack conditions are used and the nonlinear effect of domain switching near a crack tip is considered using an energy-based switching criterion proposed by Hwang et al.（Acta Metal. Mater.,1995）. In open circuit, a large depolarization field induced by domain switching makes switching much more diffcult than that in short circuit. Analysis shows that the energy release rate in short circuit is still larger than that in open circuit, and is also larger than the linear result. Consequently,whether using linear or nonlinear fracture analysis, a crack is found easier to propagate in short circuit than in open circuit, which is consistent with the experimental observations of Kounga njiwa et al.（Eng. Fract. Mech., 2006）.

关键词： Ferroelectric ceramics Crack propagation En-ergy release rate Electric boundary conditions Domain switching

Finite Element Analysis of Push-Out Test of SiC Fiber Reinforced Titanium Matrix Composites

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稀有金属材料与工程 2009年第A3期38卷 50-53页

作者： yuan M n y.ng y Q Huang B Zhang R J School of Materials Northwestern Polytechnical University Xi＇an 710072 China

Based on the interphase layer model and the spring layer model, an improved interface model was developed to evaluate the interfacial shear strength of Titanium matrix composites(TMCs) and to analyze the effects of various parameters on the interfacial properties. The results showed that the improved interface model is more suitable for calculating the interfacial properties of SiC fiber reinforced titanium matrix composites. The interfacial shear strength of SiC/Timetal-834 predicted is 500 MPa. In addition, in order to better understand the interfacial properties of composites, some push out phenomenon were analyzed.

关键词：复合材料剪切强度碳化硅纤维物理性能