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Neural regeneration research 2025年第7期20卷 2011-2012页

作者： Sharon j.Brown rafael j.Yáñez-Muñoz Heidi r.Fuller School of Pharmacy and Bioengineering Keele UniversityKeeleUK Wolfson Center for Inher.ted Neuromuscular Disease TORCH BuildingRJAH Orthopaedic HospitalOswestryUK *** Center of Gene and Cell TherapyDepartment of Biological SciencesSchool of Life Sciences and the EnvironmentRoyal Holloway University of LondonEghamUK

Spinal muscular atrophy(SMA)is a genetic condition that results in selective lower motor neuron loss with concomitant muscle weakness and *** genetic cause of SMA was understood in 1995 when loss or impairment of the survival motor neuron 1(SMN1)gene was identified as the main contributing factor(Lefebvre et al.,1995).This,in combination with the discovery that humans have a“back-up”gene,SMN2,which can produce low levels(approximately 10%)of the full-length functional SMN pr.tein,has led to the generation of SMA-specific gene *** was traditionally classified according to age of symptom onset and developmental milestones achieved,with life expectancy and severity varying between ***,SMN2 copy number is used as a proxy for the prediction of disease severity,with higher SMN2 copy number typically being associated with reduced severity of SMA,although this relationship is not absolute:some individuals with low SMN2 copy number have less severe SMA phenotypes and vice ***,the etiology of SMA is further complicated by other factors,such as non-typical nucleotide variants and SMN2-independent modifiers of disease severity.

关键词： atrophy traditionally absolute

Preparation of neodymium-doped yttrium aluminum garnet powders and fibers

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j.urnal of rare Earths 2008年第5期26卷 670-673页

作者： r. López j. zár.te E. A. Aguilar j. Muoz-Saldaa Instituto de Investigaciones Metalurgicas UMSNH Morelia Centro de Investigación y de Estudios Avanzados del IPN Unidad Queretaro

Using nitr.te precursors, a novel spray-drying assisted citr.te gel process for the preparation of neodymium-doped yttrium alumi- num garnet （YAG） phase was developed. Synthesis of single-phase polycrystalline YAG was achieved at temperatures as low as 800 ℃ using the spray-drying methodology whilst conventional approaches currently available require 1000 ℃. Initially, a solution was prepared by mixing aluminum and yttrium nitr.tes, citric acid, etilenglycol and neodymium oxide. This solution was dried by pulverization （spray dryer） to obtain aggregated precursor powders of the compound. These aggregates were calcined at 800, 850 and 900 ℃ to determine the phase evolution from amorphous to crystalline by X-ray diffraction （XrD）. The morphology of aggregates was characterized by scanning electron microscopy （SEM） and transmission electron microscopy （teM）. Moreover, through XrD it was determined that the crystallization of YAG phase started at about 800 ℃ without any intermediate phases. The powders were composed of spherical aggregates with an average diameter of 1 um. From these powders, ceramic fibers with additions of 2at.% and 5at.% Nd, were extracted from the melt with diameters ranging from 30 um to 50 um.

关键词： spray-drying melt extraction fibers yttrium aluminum garnet rare earths

Large eddy simulation of turbulent diffusion flame combustion using a conserved scalar methodology

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航空动力学报 2007年第7期22卷 1106-1117页

作者： K. Wang z. Yang j. j. McGuirk Department of Aeronautical and Automotive EngineeringLoughborough University Loughborough Leicestershire LE11 3TU UK

The present paper describes an LES prediction of turbulent diffusion flame combustion in a simplifled axi-symmetric combustor *** calculations are carried out using a well-tested finite volume incompressible LES code which has been modified to handle variable density and reacting *** basic mixture fraction conserved scalar method *** with the chemical state relationships described by fast *** turbulence-chemistry interaction is modelled by a sub-grid PDF method and the PDF is assumed to follow a Beta-function *** LES predictions have been time-averaged over 3.5 flow-through times to gener.te the mean radial profiles of mixture fraction,product mass fraction,temperature,axial velocity and axial *** agreement of the LES predictions with the experimental data is good for all the above quantities at four different axial positions with largest differences at the first measurement *** LES method also provides information on the unsteady nature of turbulent diffusion *** turbulent reacting flows with large density ratio,it was found necessary to use a relaxation method in order to remove unphysical high-frequency fluctuations and to maintain numerical stability.

关键词：大涡模拟湍流扩散数量方法论弛豫法燃烧理论

HOT DEFOrMATION AND MArteNSITIC TrANSFOrMATION BEHAVIOrS OF Fe-32%Ni ALLOY

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Acta Metallurgica Sinica(English Letters) 2006年第2期19卷 133-138页

作者： j. Huang z. Xu Cold rolling Mill Baoshan Iron ＆ Steel Co. Ltd Shanghai 201900 China Key Laboratory for High temperature Materials and tests of Ministry of Education Shanghai Jiaotong University Shanghai 200030 China

The Hot deformation and martensitic transformation behaviors of Fe-32%Ni alloy was investigated by measurements of electrical resistance and X-ray diffraction. With the increase in strain, the austenite goes through from the work-hardened to the partial dynamcally re-crystallized and then to the completed dynamically re-crystallized. The martensitic transformation characteristics depend on the austenite states. The work-hardening in small strain is helpful to martensitic transformation due to the low dislocation density and little lattice distortion, while the high dislocation density and severe lattice distortion by the increase in strain will hinder the martensitic nucleation. Once dynamic re-crystallization （ DrX ） takes place, the martensitic transformation will be enhanced again, which is related to the heterogeneous dynamic substructures. The growing DrX grain can enhance the martensitic nucleation due to the low dislocation density near its grain boundary.

关键词： Fe-32%Ni alloy hot deformation work hardening dynamic re-crystallization martensitic transformation

Numerical investigation on the flowfield of “swallowtail” cavity for supersonic mixing enhancement

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Acta Mechanica Sinica 2009年第1期25卷 37-44页

作者： C. Wang z. j.ang z. Hu j. Lu Institute or Mechanics. Chinese Academy of Sciences 100190 Beijing China reCAPT Gyeongsang National University JinjuKyeongnam 660-701 South Korea

A ＂swallowtail＂ cavity for the supersonic combustor was proposed to serve as an efficient flame holder for scramj.ts by enhancing the mass exchange between the cavity and the main flow. A numerical study on the ＂swallow- tail＂ cavity was conducted by solving the three-dimensional reynolds-averaged Navier-Stokes equations implemented with a k-e turbulence model in a multi-block mesh. Turbu- lence model and numerical algorithms were validated first, and then test cases were calculated to investigate into the mechanism of cavity flows. Numerical results demonstr.ted that the certain mass in the supersonic main flow was sucked into the cavity and moved spirally toward the combustor walls. After that, the flow went out of the cavity at its lateral end, and finally was efficiently mixed with the main flow. The comparison between the ＂swallowtail＂ cavity and the conventional one showed that the mass exchanged between the cavity and the main flow was enhanced by the lateral flow that was induced due to the pressure gradient inside the cavity and was driven by the three-dimensional vortex ring gener.ted from the ＂swallowtail＂ cavity structure.

关键词： Supersonic mixing - Flame holder "Swallowtail" cavity - Combustion ignition Numerical simulation

TrANSFOrMATION BEHAVIOr OF Ti_(50-x/2)Ni_(50-x/2)Cu_x ALLOYS

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Acta Metallurgica Sinica(English Letters) 2006年第6期19卷 391-396页

作者： j. Wang W. j.n M.z. Cao r. Yang Institute of Metal research Chinese Academy of Sciences Shenyang 110016 China Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

Phase transformation behavior of Ti50-x/2Ni50-x/2Cux (x=2, 5, 15) alloys was investigated using differential scanning calorimetry (DSC). The results show that Ti50-x/2Ni50-x/2Cux alloys undergo a two-stage martensitic transformation on cooling and transform reversely in one stage on heating when treated at 823K for 5 hours. Heat treatment has no effect on the transformation behavior of Ti49Ni49Cu2 alloy but does influence that of Ti47.5Ni47.5Cu5 alloy and Ti42.5Ni42.5Cu15 alloy. Effect of heat treatment is related with precipitation of CuNiTi phase. The maximum recoverable elongation of Ti49Ni49Cu2 wire is about 6%.

关键词： microstructure transformation shape memory Ti-Ni-Cu

MECHANICS OF rELAXING SiGe ISLANDS ON A VISCOUS GLASS

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Acta Mechanica Sinica 2002年第5期18卷 441-456页

作者： r. Huang H. Yin j. Liang j. C. Sturm K. D. Hobart z. Suo Mechanical and Aerospace Engineering Department and Princeton Materials Institute Princeton University Center for Photonics and Optoelectronie Materials and Department of Electrical Engineering Princeton University

A process has been developed recently to fabricate a structure com- prising,from top to bottom,a SiGe thin film,a glass layer,and a Si *** SiGe film is a perfect crystal,and is under biaxial *** SiGe film is patterned into *** annealing,the glass flows and the islands *** resulting strain-free islands are used as substr.tes,to grow epitaxial optoelectronic *** article describes a series of studies on the annealing process,combining experiment and theory.A small island relaxes by expansion,starting at the edges and diffusing to the center.A large island wrinkles before the expansion reaches the *** some time,the wrinkles either disappear,or cause the island to fracture. We model the island as an elastic plate,and the glass layer as a viscous *** strains in the islands are measured by X-ray diffraction and raman spectroscopy,and the wrinkle amplitudes by atomic force *** data are compared with the theoretical *** determine the conditions under which the islands relax by expansion without significant wrinkling,and demonstr.te that a cap layer suppresses wrinkles,relaxing a large island crack-free.

关键词： semiconductor fabrication stress relaxation viscous flow elastic plate fracture

THEOrETICAL ANALYSIS FOr THE MOTION AND teMPErATUrE OF MELT DrOPLETS IN SPrAY DEGASSING PrOCESS

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Acta Metallurgica Sinica(English Letters) 2007年第3期20卷 193-198页

作者： r.z. Wu z.K. Qu B.D. Sun D. Shu j. Wang College of Materials Science ＆ Chemical Engineering Harbin Engineering University Harbin 150001 China State Key Laboratory of Metal Matrix Composites Shanghai Jiao Tong University Shanghai 200030 China Department of Chemistry Harbin Normal University Harbin 150025 China

The motion of melt droplets in spray degassing process was analyzed theoretically. The height of the treatment tank in spray degassing process couM be determined by the results of theoretical calculation of motion of melt droplets. To know whether the melt droplets wouM solidify during spraying process, the balance temperature of melt droplets was also theoretically analyzed. Then proof experiments for theoretical results about temperature of melt droplets were carried. In comparison, the experimental results were nearly similar to the calculation results,

关键词： spray degassing hydrogen removal aluminum melt motion temperature

Development and application of functional gene arrays for microbial community analysis

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中国有色金属学会会刊：英文版 2008年第6期18卷 1319-1327页

作者： z. L. HE j. D. VAN NOSTrAND L.Y. WU j. z. zHOU Institute for Environmental Genomics Department of Botany and Microbiology University of Oklahoma Norman OK 73019 USA

功能的基因标记能关于功能的基因差异和微生物引起的社区的潜在的活动提供重要信息。尽管 microarray 技术成功地被使用了为纯文化学习基因表示，简单、人工的微生物引起的社区，改编如此的一种技术分析复杂微生物引起的社区仍然以设计... 详细信息

功能的基因标记能关于功能的基因差异和微生物引起的社区的潜在的活动提供重要信息。尽管 microarray 技术成功地被使用了为纯文化学习基因表示，简单、人工的微生物引起的社区，改编如此的一种技术分析复杂微生物引起的社区仍然以设计，样品准备，和数据分析提出很多挑战。这个工作集中于功能的基因数组(FGA ) 的开发和应用程序为微生物引起的社区研究指向关键功能的基因标记。一些与 FGA 有关明确地给问题调音，例如 oligonucleotide 探查设计， nucleic 酸抽取和纯化，数据分析，特性，敏感，和量的能力详细被讨论。最近的研究证明了 FGA 能从许多自然环境关于微生物引起的社区提供特定、敏感、潜在地量的信息并且控制生态系统。这种技术被期望革命化微生物引起的社区的分析，并且连接微生物引起的结构到生态系统工作。

关键词：微数列应用函数基因标记微生物种群

PrEPArATION AND COrrOSION rESISTANCE OF NiP/TiO_2 COMPOSIte FILM ON CArBON SteEL IN SULFUrIC ACID SOLUTION

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Acta Metallurgica Sinica(English Letters) 2006年第2期19卷 117-123页

作者： L.z. Song S.z. Song j. zhao School of Environment ＆ Chemical Engineering Yanshan University Qinhuangdao 066004 China School of Materials Science and Engineering Tianjin University Tianjin 300072 China

A NiP/TiO2 composite film on carbon steel was prepared by electroless plating and sol-gel composite process. An artificial neural network was applied to optimize the prepared condition of the composite film. Corrosion behavior of the NiP/TiO2 composite film was investigated by polarization resistance measurement, anode polarization, ESEM （environmental scanning electron microscopy） and EIS （electrochemical impedance spectroscopy） measurements. results showed that the NiP/ TiO2 composite film has a good corrosion resistance in 0.5mol/L H2SO4 solution. The element valence of the composite film was characterized by XPS （X-ray photoelectron spectroscopy） spectrum, and an anticorrosion mechanism of the composite film was discussed.

关键词： electroless plating and sol-gel composite process artificial neural network NiP/TiO2 composite film corrosion resistance