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Combined conventional/antioxidant“Astaxanthin”treatment for male infertility:a double blind,randomized trial

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Asian Journal of Andrology 2005年第3期7卷 257-262,页

作者： f.h.Comhaire Y.El Garem A.Mahmoud f.Eertmans f.Schoonians Department of Medical and Urological Andrology Ghent University HospitalGent B 9000Belgium Department of AndrologyAlexandria University HospitalAlexandriaEG 21544Egypt Department of Andrology Alexandria University HospitalAlexandriaEG 21544Egypt Department of Medical and Urological Andrology Ghent University HospitalGent B 9000Belgium

Aim： To evaluate the treatment of male infertility with a strong natural antioxidant, in addition to conventional treatment. Methods： Using a double blind, randomized trial design, 30 men with infertility of ≥12 months and female partners with no demonstrable cause of infertility received conventional treatment according to the guidelines of the World health Organization （WhO）, and either a strong antioxidant Astaxanthin 16 rag/day （AstaCarox, AstaReal AB, Gustavsberg, Sweden） or placebo for 3 months. The effects of treatment on semen parameters, reactive oxygen species （ROS）, zona-free hamster oocyte test, serum hormones including testosterone, luteinizing hormone （Lh）, follicle stimulating hormone （f.h） and Inhibin B, and spontaneous or intrauterine insemination （IUI）-induced pregnancies were evaluated. Results： ROS and Inhibin B decreased significantly and sperm linear velocity increased in the Astaxanthin group （n = 11）, but not in the placebo group （n = 19）. The results of the zona-free hamster oocyte test tended to improve in the Astaxanthin group in contrast with the placebo group, though not reaching statistical significance. The total and per cycle pregnancy rates among the placebo cases （10.5 % and 3.6 %） were lower compared with 54.5 % and 23. 1% respectively in the Astaxanthin group （P=0.028; P=0.036）. Conclusion： Although the present study suggests a positive effect of Astaxanthin on sperm parameters and fertility, the results need to be confirmed in a larger trial before recommending Astaxanthin for the complementary treatment of infertile men. （Asian J Androl 2005 Sep; 7： 257-262）

关键词： male infertility antioxidant astaxanthin ROS treatment pregnancy

A new thermodynamically stable Nb_(2)Ni intermetallic compound phase revealed by peritectoid transition within binary Nb-Ni alloy system

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Journal of Materials Science & Technology 2022年第5期100卷 246-253页

作者： J.f.Zhao h.P.Wang B.Wei School of Physical Science and Technology Northwestern Polytechnical UniversityXi’an 710072China

A new intermetallic compound of thermodynamically stable Nb_(2)Ni phase is discovered within Nb-Ni binary system,refreshing the current situation that there are only three stable intermediate phases of Nb_(7)Ni_(6),NbNi_(3) and NbNi_(8).The new stable phase is generated from the peritectoid transition:(Nb)+Nb_(7)Ni_(6)→Nb_(2)Ni,and the transformation temperature is 1533 *** refreshes the current equilibrium Nb-Ni binary phase *** is confirmed by transmission electron microscopy and the annealing experiments,which is determined to be the fCC structure(Pearson:cf96,space grope:fd-3m O2,a=11.888A).furthermore,the equilibrium properties of Nb_(2)Ni phase are produced by density functional theory,including the formation energy,cohesive energy,bulk modulus and lattice constant.

关键词： Intermetallic compound Peritectoid transition Transmission electron microscopy Density functional theory Nb alloy

A strategy for designing stable nanocrystalline alloys by thermo-kinetic synergy

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Journal of Materials Science & Technology 2020年第8期36卷 21-31页

作者： h.R.Peng B.S Liu f.Liu State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an710072China School of Materials and Chemical Engineering Xi’an Technological UniversityXi’an710021China Analytical and Testing Center Northwestern Polytechnical UniversityXi’an710072China

Aiming to design stable nanocrystalline(NC)materials,so far,it has been proposed to construct nanostructure stability maps in terms of thermodynamic parameters,while kinetic stabilization has seldom been considered,despite the synergy of thermodynamics and ***,the thermodynamically stabilized NC materials may be easily subjected to grain growth at high temperatures due to the weakly kinetic *** from the thermo-kinetic synergy,a stabilization criterion is proposed as a function of intrinsic solute parameters(*** activation energy for bulk diffusion and the segregation enthalpy),intrinsic solvent parameters(*** intrinsic activation energy for GB migration and the GB energy)and processing parameters(*** grain size,the temperature and the solute concentration).Using first-principles calculations for a series of combinations between fifty-one substitutional alloying atoms as solute atoms and fe atom as fixed solvent atom,it is shown that the thermal stability neither simply increases with increasing the segregation enthalpy as expected by thermodynamic stabilization,nor monotonically increases with increasing the activation energy for bulk diffusion as described by kinetic *** combination of thermodynamic and kinetic contributions,the current stabilization criterion evaluates quantitatively the thermal stability,thus permitting convenient comparisons among NC materials involved by various combinations of the solute atoms,the solvent atoms,or the processing *** of this thermo-kinetic stabilization criterion has been tested by current experiment results of fe-Y alloy and previously published data of fe-Ni,fe-Cr,fe-Zr and fe-Ag alloys,etc.,which opens a new window for designing NC materials with sufficiently high thermal stability and sufficiently small grain size.

关键词： Thermo-kinetic Synergy Criterion Thermal stability Nanocrystalline materials

Relationship between CO_2 Sensor Voltage Response and Phase Equilibrium of Solid Electrolyte Na,K-β/β″-Al_2O_3

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Journal of Materials Science & Technology 2003年第5期19卷 450-452页

作者： J.h.YANG h.Nafe f.Aldinger D.S.YAN ShanghaiInstituteofCeramics ChineseAcademyofSciencesShanghai200050China Max-Planck-InstitutfurMetallforschung PulvermetallurgischesLaboratoratiumHeisenbergstrasse570569StuttgartGermany

关键词： CO2 sensor Phase equilibrium Solid electrolyte Na K-β/β'-Al2O3

Large deformation and wrinkling analyses of bimodular structures and membranes based on a peridynamic computational framework

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Acta Mechanica Sinica 2019年第6期35卷 1226-1240页

作者： h.Li Y.G.Zheng Y.X.Zhang h.f.Ye h.W.Zhang Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of ChinaChengdu 610200China International Research Center for Computational Mechanics State Key Laboratory of Structural Analysis for Industrial EquipmentDepartment of Engineering MechanicsFaculty of Vehicle Engineering and MechanicsDalian University of TechnologyDalian 116024China

In this paper,the quasi-static large deformation,wrinkling and fracture behaviors of bimodular structures and membranes are studied with an implicit bond-based peridynamic computational ***,the constant and tangential stiffness matrices of the implicit peridynamic formulations for the nonlinear problems are derived,*** former is con structed from the linearization of the bond strain on the basis of the geometric approximation while the latter is established according to the linearization of the pairwise force by using first-order Taylor’s ***,a bimodular material model in peridynamics is developed,in which the tensile or compressive behavior of the material at each point is conveniently described by the tensile or compressive states of the bonds in its ***,the bimodular material model is extended to deal with the wrinkling and fracture problems of membranes by setting the compressive micro-modulus to be *** addition,the incremental-iterative algorithm is adopted to obtain the convergent solutions of the nonlinear ***,several representative numerical examples are presented and the results demonstrate the accuracy and efficiency of the proposed method for the large deformation,wrinkling and fracture analyses of bimodular structures and membranes.

关键词： Bimodular structures Wrinkling membranes fracture problems Peridynamics Implicit numerical algorithm

Trans-scale mechanics: looking for the missing links between continuum and micro/nanoscopic reality

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Acta Mechanica Sinica 2008年第2期24卷 111-126页

作者： Y.L.Bai h.Y.Wang M.f.Xia f.J.Ke State Key Laboratory of Non-linear Mechanics (LNM) Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China State Key Laboratory of Non-linear Mechanics (LNM) Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China Department of Physics Peking University Beijing 100871 China State Key Laboratory of Non-linear Mechanics (LNM) Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China Department of Applied Physics Beihang University Beijing 100083 China

Problems involving coupled multiple space and time scales offer a real challenge for conventional frame-works of either particle or continuum mechanics. In this paper, four cases studies （shear band formation in bulk metallic glasses, spallation resulting from stress wave, interaction between a probe tip and sample, the simulation of nanoindentation with molecular statistical thermodynamics） are provided to illustrate the three levels of trans-scale problems （problems due to various physical mechanisms at macro-level, problems due to micro-structural evolution at macro/micro-level, problems due to the coupling of atoms/ molecules and a finite size body at micro/nano-level） and their formulations. Accordingly, non-equilibrium statistical mechanics, coupled trans-scale equations and simultaneous solutions, and trans-scale algorithms based on atomic/molecular interaction are suggested as the three possible modes of trans-scale mechanics.

关键词： Multi-scale Missing-links Continuum mechanics Particle mechanics Trans-scale mechanics

Decomposition of Molecular Motions into Translational, Rotational, and Intramolecular Parts by a Projection Operator Technique

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Communications in Computational Physics 2009年第7期6卷 231-246页

作者： f.Y.hansen h.Taub Department of Chemistry Technical University of DenmarkIK 207 DTUDK-2800 LyngbyDenmark Department of Physics and Astronomy and the University of Missouri Research Reactor University of MissouriColumbiaMissouri 65211USA

The motion of the atoms in a molecule may be described as a superposition of translational motion of the molecular center-of-mass,rotational motion about the principal molecular axes,and an intramolecular motion that may be associated with vibrations and librations as well as molecular conformational *** have constructed projection operators that use the atomic coordinates and velocities at any two times,t=0 and a later time t,to determine the molecular center-of-mass,rotational,and intramolecular motions in a molecular dynamics *** model-independent technique facilitates characterization of the atomic motions within a system of complex molecules and is important for the interpretation of experiments that rely on time correlation functions of atomic and molecular positions and *** application of the projection operator technique is illustrated for the inelastic neutron scattering functions and for the translational and rotational velocity autocorrelation functions.

关键词： Molecular dynamics projection operator correlation functions scattering functions translational motion rotational motion intramolecular motion

Green's function solution for transient heat conduction in annular fin during solidification of phase change material

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Applied Mathematics and Mechanics(English Edition) 2012年第10期33卷 1265-1274页

作者： A.h.MOSAffA f.TALATI M.A.ROSEN h.BASIRAT-TABRIZI faculty of Mechanical Engineering University of Tabriz faculty of Engineering and Applied Science University of Ontario Institute of TechnologyL1H 7K4 OshawaOntarioCanada Department of Mechanical Engineering Amirkabir University of Technology

The Green＇s function method is applied for the transient temperature of an annular fin when a phase change material （PCM） solidifies on it. The solidification of the PCMs takes place in a cylindrical shell storage. The thickness of the solid PCM on the fin varies with time and is obtained by the Megerlin method. The models are found with the Bessel equation to form an analytical solution. Three different kinds of boundary conditions are investigated. The comparison between analytical and numerical solutions is given. The results demonstrate that the significant accuracy is obtained for the temperature distribution for the fin in all cases.

关键词： annular fin analytical solution Green's function phase change material(PCM) solidification thermal energy storage

full-band error control and crack-free surface fabrication techniques for ultra-precision fly cutting of large-aperture KDP crystals

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frontiers of Mechanical Engineering 2017年第2期12卷 193-202页

作者： f. h. ZhANG S. f. WANG C. h. AN J. WANG Q. XU Department of Mechanical Engineering Harbin Institute of TechnologyHarbin 150001 China Chengdu fine Optical Engineering Research Center Chengdu 610041China

Large-aperture potassium dihydrogen phos- phate （KDP） crystals are widely used in the laser path of inertial confinement fusion （ICf） systems. The most common method of manufacturing half-meter KDP crystals is ultra-precision fly cutting. When processing KDP crystals by ultra-precision fly cutting, the dynamic characteristics of the fly cutting machine and fluctuations in the fly cutting environment are translated into surface errors at different spatial frequency bands. These machin- ing errors should be suppressed effectively to guarantee that KDP crystals meet the full-band machining accuracy specified in the evaluation index. In this study, the anisotropic machinability of KDP crystals and the causes of typical surface errors in ultra-precision fly cutting of the material are investigated. The structures of the fly cutting machine and existing processing parameters are optimized to improve the machined surface quality. The findings are theoretically and practically important in the development of.high-energy laser systems in China.

关键词： ultra-precision fly cutting large-aperture KDP crystals spatial frequency processing error