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Journal of Materials Science & Technology 2009年第2期25卷 277-280页

作者： M. cheng S.h. Zhang Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

Research results on the viscous flow deformation behavior of bulk amorphous alloy in different systems are reviewed. The material exhibits an ideal Newtonian fluid at a high temperature. Analytical solution of lamellar fluid flow behavior is used to discuss the viscous flow behavior of the bulk amorphous alloy in the supercooled liquid state. A material model, which describes such deformation behavior of Mg6oCusoYlo amorphous alloy, is introduced into the finite element method of microformin8 process. Surface feature size was investigated and found not sensitive to the micro formability. Bulk amorphous alloy may possibly be applied to microelectro-mechanical-systems （MEMS） fabrication.

关键词： Bulk amorphous alloy Supercooled liquid state Micro formability Lamellar fluid flow

Epitaxial growth of Ge_(1-x)Sn_x films with x up to 0.14 grown on Ge(00l) at low temperature

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Chinese Physics B 2014年第8期23卷 591-594页

作者：陶平黄磊 cheng h h 王焕华吴小山 Laboratory of Solid State Microstructures Nanjing University National Taiwan University Center for Condensed Matter Sciences Beijing Synchrotron Radiation Facility (BSRF) Institute of High Energy Physics

We characterize the structures of Ge1-xSnx films with x up to 0.14 grown on Ge （001） by molecular-beam epitaxy at low temperature. The results show that Ge1-xSnx films are fully strained even at high Sn composition. The in-plane lattice parameters remain exactly the same as that of the substrate. Depth sensitivity analysis of the lattice parameters indicates that the strains of the epitaxial films are all in homogeneity. The films are fully strained. Poisson ratios, the force constants for the bonds between Ge and Sn are estimated and discussed in the present paper. Raman results show Ge-Ge, Ge-Sn, Sn-Sn vibrational modes. The Sn-Sn bond aggregation may respond to the high quality of our films. The fully strained epitaxy films with high content of Sn may be useful in designing the high quality GeSn films.

关键词： GeSn films high resolution X-ray diffraction fully-strained Raman measurements

The dimension split element-free Galerkin method for three-dimensional potential problems

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Acta Mechanica Sinica 2018年第3期34卷 462-474页

作者： Z.J.Meng h.cheng L.D.Ma Y.M.cheng Shanghai Institute of Applied Mathematics and Mechanics Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai University School of Applied Science Taiyuan University of Science and Technology Department of Civil Engineering Shanghai University School of Materials Science and Engineering Taiyuan University of Science and Technology

This paper presents the dimension split element-free Galerkin （DSEFG） method for three-dimensional potential problems, and the corresponding formulae are obtained. The main idea of the DSEFG method is that a three-dimensional potential problem can be transformed into a series of two-dimensional problems. For these two-dimensional problems, the improved moving least-squares （IMLS） approximation is applied to construct the shape function, which uses an orthogonal function system with a weight function as the basis functions. The Galerkin weak form is applied to obtain a discretized system equation, and the penalty method is employed to impose the essential boundary condition. The finite difference method is selected in the splitting direction. For the purposes of demonstration, some selected numerical examples are solved using the DSEFG method. The convergence study and error analysis of the DSEFG method are presented. The numerical examples show that the DSEFG method has greater computational precision and computational efficiency than the IEFG method.

关键词： Dimension split method Improved moving least-squares (IMLS) approximation Improved element-free Galerkin (IEFG) method Finite difference method (FDM) Dimension split element-free Galerkin (DSEFG) method Potential problem

Modeling of cable vibration effects of cable-stayed bridges

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Earthquake Engineering and Engineering Vibration 2002年第1期1卷 74-85页

作者： S.h.cheng David T.Lau Department of Civil and Environmental Engineering Carleton UniversityOttawaOntarioCanadaPost-doctoral fellow Department of Civil and Environmental Engineering Carleton UniversityOttawaOntarioCanada Professor

The analysis of dynamic responses of cable-stayed bridges subjected to wind and earthquake loads generally considers only the motions of the bridge deck and *** influence of the stay cable vibration on the responses of the bridge is either ignored or considered by approximate *** transverse vibration of the stay cables,which can be significant in some cases,are usually neglected in previous *** the present study,a new three-node cable element has been developed to model the transverse motions of the *** interactions between the cable behavior and the other parts of the bridge superstructure are considered by the concept of dynamic *** nonlinear effect of the cable caused by its self-weight is included in the *** examples are presented to demonstrate the accuracy and efficiency of the proposed model. The impact of cable vibration behavior on the dynamic characteristics of cable-stayed bridges is discussed.

关键词： cable-stayed bridges cable vibration dynamics finite elements long-span structures

Glucocorticoids and prostate cancer treatment： friend or foe？

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Asian Journal of Andrology 2014年第3期16卷 354-358页

作者： Bruce Montgomery heather h cheng James Drechsler Elahe A Mostaghel Department of Medicine University of Washington Seattle Seattle Cancer Care Alliance Seattle Division of Clinical Research Fred Hutchinson Cancer Research Center Seattle Washington USA.

Glucocorticoids have been used in the treatment of prostate cancer to slow disease progression, improve pain control and offset side effects of chemo- and hormonal therapy. however, they may also have the potential to drive prostate cancer growth via mutated androgen receptors or glucocorticoid receptors （GRs）. In this review we examine historical and contemporary use of glucocorticoids in the treatment of prostate cancer, review potential mechanisms by which they may inhibit or drive prostate cancer growth, and describe potential means of defining their contribution to the biology of prostate cancer.

关键词： androgen receptor dihydrotestosterone glucocorticoid receptor glucocorticoids prostate cancer steroids testosterone

NumericalModeling of ElasticWave Propagation in a Fluid-Filled Borehole

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Communications in Computational Physics 2008年第1期3卷 33-51页

作者： Arthur C.h.cheng Joakim O.Blanch Cambridge GeoSciences 14090 Southwest FreewaySuite 300Sugar LandTX 77478USA Nexus GeoSciences 14090 Southwest FreewaySuite 240Sugar LandTX 77478USA previously at SensorWise Inc.2908 RodgerdaleHoustonTX 77042USA.

We review the methods of simulating elastic wave propagation in a *** considered two different approaches: a quasi-analytic approach using theDiscreteWavenumber SummationMethod, and the purely numerical Finite DifferenceMethod. We consider the special geometry of the borehole and discuss the problem incylindrical coordinates. We point out some numerical difficulties that are particularlyunique to this problem in cylindrical coordinates.

关键词： Acoustic borehole numerical modeling.

The relationship of Imp2 and DR3 genes with susceptibility to type Ⅰ diabetes mellitus in south China han population

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World Journal of Gastroenterology 2000年第1期6卷 111-114页

作者： Ding hL cheng h Fu ZZ Deng QL Yan L Yan T Department of Endocrinology Sun Yat-Sen Memorial HospitalSun Yat-Sen University of Medical SciencesGuangzhou 510120China

AIN To study the relationship of Imp2 and DR3genes with type Ⅰ diabetes *** Imp2 genotypes and DR3 wereidentified in 68 patients with type Ⅰ diabetesmellitus(Ⅰ-DM)and 71 healthy ***,Ⅰ-DM patients and controls were respectivelyallocated into DR3-positive and *** frequencies of Imp2 and DR3 genein random subjects,and Imp2 genotypes in DR3-matched subjects were compared between Ⅰ-DMpatients and *** the same time,Ⅰ-DMpatients were divided into 3 groups based on theonset age of diabetics:group A≤14 years,group B 15-30 years and group C≥31 *** The frequency of DR3 in Ⅰ-DMpatients was significantly higher than that incontrols(47% vs 21%,Phigher in group A than that in groupB+C(70% vs 36%,x^2=7.07,Pherewas a significant difference among groups withdifferent onset age of diabetics(x^2=8.19,rp=0.33,Phefrequency of Imp2.R/R in Ⅰ-DM patients waslower(43% vs 61%,Phhigher(53% vs 28%,Phan that incontrols,and there was no significant differenceamong groups with different onset age *** DR3-positive subjects,thefrequency of Imp2.R/R in Ⅰ-DM patients waslower(47% vs 87%,Ph higher(47% vs 13%,Phan that *** DR3-negative subjects,thefrequency of Imp2.R/h in Ⅰ-DM patients washigher than that in controls(58% vs 32%,Phe frequency of Imp2-R/R and Imp2h/h was not significantly different betweenthese two *** DR3 gene may be one of thesusceptible genes of Ⅰ-DM,and significantlyrelated to the onset age of diabetics,and thepersons with DR3 may have an younger onsetage of *** Imp2-R/R may be theprotective genotype of Ⅰ-DM,and Imp2-R/h thesusceptible *** were not affectedby DR3 ***-2 genotypes were not relatedwith the onset age of diabetics.

关键词： Subject headings diabetes mellitus Imp2 genes DR3 genes polymerase chain reaction restriction fragment length polymorphism genetic susceptibility

Defect control at nanoscale and flux pinning enhancement in MgB_2 superconductor

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Journal of Modern Transportation 2012年第2期20卷 65-69页

作者： C.h.cheng C.SORRELL School of Materials Science and Engineering University of New South Wale

Defect control at nanoscale of MgB2 by doping various nanoparticles including Ti, C, nano-diamond, and hOB4, and their roles played to enhance flux pinning force in MgB2 are compared and analyzed. These nanodopants have different chemical and physical properties, thus bring about different pinning efficiency, especially nanodopants with strong magnetic moment are particularly interesting as pinning centers in MgB2 since magnetic impurities usually have a stronger interaction with magnetic flux line than nonmagnetic impurities and may exert a stronger force to trap the flux lines when they are properly introduced into the superconducting matrix.

关键词： MgB2 flux pinning nano-pinning centers microstrueture control

Surface hydrophobicity: effect of alkyl chain length and network homogeneity

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Frontiers of Chemical Science and Engineering 2021年第1期15卷 90-98页

作者： Wenqian Chen Vikram Karde Thomas N.h.cheng Siti S.Ramli Jerry Y.Y.heng Department of Chemical Engineering Imperial College LondonLondonSW72AZUK Department of Food Technology Faculty of Applied SciencesUniversiti Teknologi MARA(UiTM)Shah AlamSelangorMalaysia

Understanding the nature of hydrophobicity has fundamental importance in environmental *** spherical silica nanoparticles(diameter=369±7 nm)as the model material,the current study investigates the relationship between the alkyl chain network and *** alkyl silanes with different chain length(triethoxymethylsilane(C1)***(octyl)silane(C8))were utilised separately for the functionalisation of the *** contact angle and inverse gas chromatography results show that the alkyl chain length is essential for controlling hydrophobicity,as the octyl-functionalised nanoparticles were highly hydrophobic(water contact angle=150.6°±6.6°),whereas the methyl-functionalised nanoparticles were hydrophilic(i.e.,water contact angle=0°,similar to the pristine nanoparticles).The homogeneity of the octyl-chain network also has a significant effect on hydrophobicity,as the water contact angle was reduced significantly from 148.4°±3.5°to 30.5°±1.0°with a methyl-/octyl-silane mixture(ratio=160:40µL·g^(–1) nanoparticles).

关键词： hydrophobicity surface energy wettability alkyl chain network silica nanoparticle

Fabrication and characteristics of nitrogen-doped nanocrystalline diamond/p-type silicon heterojunction

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Nano-Micro Letters 2010年第1期2卷 56-59页

作者： D.Lu h.D.Li S.h.cheng J.J.Yuan X.Y.Lv State Key Laboratory of Superhard Materials Jilin University

Nitrogen-doped nanocrystalline diamond films(N-NDFs)have been deposited on p-type silicon(Si)by microwave plasma chemical vapor *** reaction gases are methane,hydrogen,and nitrogen without the conventional argon(Ar).The N-NDFs were characterized by X-ray diffraction,Raman spectroscopy,and scanning electron *** grain sizes are of 8~10 nm in *** N-NDF shows n-type behavior and the corresponding N-NDF/p-Si heterojunction diodes are realized with a high rectification ratio of 102 at^7.8 V,and the current density reaches to1.35 A/cm2 at forward voltage of 8.5 *** findings suggest that fabricated by Ch_4/h_2/N_2 without Ar,the N-NDFs and the related rectifying diodes are favorable for achieving high performance diamond-based optoelectronic devices.

关键词： Nanocrystalline diamond film Chemical vapor deposition Nitrogen doped heterojunction diodes Current-voltage characteristics