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CAlCUlATION OF 3-D TRANSIENT TEmPERATURE FIElD DURING lASER TRANSFORmATION HARDENING PROCESS

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Acta metallurgica Sinica(English letters) 2000年第2期13卷 806-810页

作者： l. W Zhang, R.S. Wang, j. Th.m.De Hosson, Y.l. Xia and F. G. Wang 1) The State Key lab. for materials modification by laser, Ion and Electron Beams, Dalian University of Technology, Dalian 116023, China 2) Department of Applied Physics, University of Gro

A three-dimensional transient heat transfer model for laser transformation hardening process has been developed in this paper. The finite size of the laser treated sample, the surface heat loss of the sample, the latent heat of phase transformation and the temperature dependence of thermal properties of materials were considered. The heat source was considered as a moving Gaussian heat flux with a constant velocity. Three-dimension unequally spatial grid explicit finite difference equations, alternating direction implicit finite difference equations and implicit finite difference equations were deduced respectively. Three programs to calculate the temperature field were developed using Fortran language. The transient temperature fields of C22, 42Crmo, C60 steel samples during laser transformation hardening process were calculated using these programs, and the widths and depths of laser transformation hardening zones were also predicted. C22, 42Crmo, C60 steel samples were treated by CO_2 laser,the widths and depths of laser transformation hardening zones of these samples were also measured experimentally. The calculated widths and depths of laser transformation hardening zones are in good agreement with the experimental results.

关键词： temperature field laser transformation hardening steel

Self-adjoint Extensions for the Neumann laplacian and Applications

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Acta mathematica Sinica,English Series 2006年第3期22卷 879-906页

作者： S.A.NAzar.V j.SOKOlOWSKI Institute of mechanical Engineering Problems V.O.Bolshoy pr.61 199178 St Petersburg Russia Institut Elie Cartan laboratoire de mathématiques Université Henri Poincaré NancyI B.P.239 54506 Vandoeuvrelès Nancy Cedex France and Systems Research Institute of the Polish Academy of Sciences ul.Newelska601-447Warszawa Poland

A new technique is proposed for the analysis of shape optimization problems. The technique uses the asymptotic analysis of boundary value problems in singularly perturbed geometrical domains. The asymptotics of solutions are derived in the framework of compound and matched asymptotics expansions. The analysis involves the so-called interior topology variations. The asymptotic expansions are derived for a model problem, however the technique applies to general elliptic boundary value problems. The self-adjoint extensions of elliptic operators and the weighted spaces with detached asymptotics are exploited for the modelling of problems with small defects in geometrical domains, The error estimates for proposed approximations of shape functionals are provided.

关键词： shape optimization asymptotic expansions self-adjoint extension weighted spaces with detached asymptotics topological derivatives

Correlation Functions, Universal Ratios and Goldstone mode Singularities in n-Vector models

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Communications in Computational Physics 2014年第5期15卷 1407-1430页

作者： j.Kaupuzs R.V.N.melnik j.Rimsans Institute of mathematics and Computer Science University of Latvia29 Rai¸na BoulevardLV1459RigaLatvia Institute of mathematical Sciences and Information Technologies University of Liepaja14 Liela StreetLiepaja LV-3401Latvia Wilfrid laurier University WaterlooOntarioCanadaN2L 3C5.

Correlation functions in the O(n)models below the critical temperature are *** on monte Carlo(mC)data,we confirm the fact stated earlier by Engels and Vogt,that the transverse two-plane correlation function of the O(4)model for lattice sizes about l=120 and small external fields h is very well described by a Gaussian ***,we show that fits of not lower quality are provided by certain non-Gaussian *** have also tested larger lattice sizes,up to l=*** Fourier-transformed transverse and longitudinal two-point correlation functions have Goldstone mode singularities in the thermodynamic limit at k→0 and h=+0,i.e.,G_(⊥)(k)≈ak−λ_(⊥)and G_(||)(k)≈bk−λk,*** a and b are the amplitudes,k=|k|is the magnitude of the wave vector *** exponentsλ_(⊥),λk and the ratio bm^(2)/a^(2),where m is the spontaneous magnetization,are universal according to the GFD(grouping of Feynman diagrams)*** we find that the universality follows also from the standard(Gaussian)theory,yielding bm^(2)/a^(2)=(n−1)/*** mC estimates of this ratio are 0.06±0.01 for n=2,0.17±0.01 for n=4 and 0.498±0.010 for n=*** to these and our earlier mC results,the asymptotic behavior and Goldstone mode singularities are not exactly described by the standard *** is expected from the GFD *** have found appropriate analytic approximations for G_(⊥)(k)and G_(||)(k),well fitting the simulation data for small *** have used them to test the Patashinski-Pokrovski relation and have found that it holds approximately。

关键词： n-component vector models correlation functions monte Carlo simulation Goldstone mode singularities.

Development of low Carbon microalloyed High Strength Ultra-Thin Cast Strip Products Produced by the Castrip~ Process With Excellent Strength-Ductility Properties

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journal of Iron and Steel Research(International) 2011年第S1期18卷 846-850页

作者： C.R. Killmore K.R. Carpenter H.R. Kaul D.G. Edelman j.m. Cairney S.P. Ringer j.G. Williams P.C. Campbell W.N. Blejde BlueScope Steel Five Islands Road Pt Kembla 2500 Australia Nucor Steel Indiana 4537 S. Nucor Rd. Crawfordsville IN 47933 USA Australian Centre for microscopy and microanalysis University of Sydney NSW 2006 Australia Castrip llC1915 Rexford Rd. Charlotte NC 28211 USA

The CASTRIP* process produces a range of high strength Ultra-thin Cast Strip (UCS) products (380-550 mPa) in thicknesses between 0.9 mm and 1.5 mm, which is very challenging to produce via conventional hot and cold rolled processing routes. The twin roll CASTRIP process fully exploits the hardenability and strengthening potential of Nb in a low C-mn-Nb-V microalloyed steel type. Significant microstructural strengthening from solute Nb was obtained, even at low microalloying levels, as well as modest mn additions, through enhancing the hardenability and further strengthening was obtained in coated products by exploiting age hardening during processing on a continuous hot dip galvanising line. Atom probe tomography and TEm determined that Nb was retained in solid solution and subsequent age hardening resulted from the formation of Nb and V rich nanosized particles. Age hardening was achieved without loss of ductility producing galvanised strip with an excellent strength-ductility combination (Y.S. >600 mPa, T.E. >10%).

关键词： strip casting microalloying niobium ntom probe tomography age hardening high strength CASTRIP Process

New Zealand deer farming and management systems for quality velvet antler production:An overview:

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New Zealand deer farming and management systems for quality ...

第二届中国鹿业发展大会

作者： A j Pearse j m Tacon R E Griffiths Deer Industry New Zealand PO Box 10702 Wellington6143New Zealand

New Zealand’s 40 year old modem deer farming systems are based on the extensive natural pastoral farming of red deer and elk(Cervus elaphus ssp).Within the industry’s～3000 farmers(most whom produce venison),specialists farm an adult velvet antler herd producing approximately 450 tonnes of velvet antler *** systems concentrate on both genetic improvements,which have been spectacular,and meeting the nutritional demands for growth of quality *** agreed systems are developed for

关键词： deer farming velvet antler quality production quality assurance New Zealand Red deer (Chilu) Elk-Wapiti(malu) National Velvetting Standards Body

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少自由度并联机构的位移流形综合理论

中国科学（E辑） 2004年第9期34卷 1011-1020页

作者：李秦川黄真 j.m.Hervé 浙江理工大学集成技术中心杭州310033 燕山大学机器人研究中心秦皇岛066004 Ecole Centrale Paris France

提出了少自由度并联机构基于李群理论的位移流形综合理论.给出了全部9类少自由度并联机构的机构位移流形,分支位移流形和保证所有分支位移流形之交集为期望机构位移流形的几何条件.利用位移子群乘法运算的封闭性,可得到不同结构的分支... 详细信息

提出了少自由度并联机构基于李群理论的位移流形综合理论.给出了全部9类少自由度并联机构的机构位移流形,分支位移流形和保证所有分支位移流形之交集为期望机构位移流形的几何条件.利用位移子群乘法运算的封闭性,可得到不同结构的分支运动链.使用这些分支运动链,满足相应几何条件即可构建出具有期望自由度的并联机构,并且其优点是无需判别机构的瞬时性,依据此原理可以进一步根据多方面的实际需要综合新的机型.

关键词：少自由度并联机构型综合位移子群 lie群位移流形

西太平洋新近纪的俯冲起始模型及俯冲带参数分析

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中国科学：地球科学 2023年第3期53卷 461-480页

作者：李泯黄松郝天珧董淼徐亚张健何庆禹方桂中国科学院地质与地球物理研究所中国科学院油气资源研究重点实验室北京100029 中国科学院大学地球与行星科学学院北京100049 中国科学院地球科学研究院北京100029

新近纪是研究俯冲起始的重要时期,在西太平洋地区形成了众多的俯冲带,包括Ryukyu俯冲带、manila俯冲带、Philippine俯冲带、北Sulawesi俯冲带、Halmahera俯冲带、New Britain俯冲带、Solomon俯冲带以及New Hebrides俯冲带等.但有关这些... 详细信息

新近纪是研究俯冲起始的重要时期,在西太平洋地区形成了众多的俯冲带,包括Ryukyu俯冲带、manila俯冲带、Philippine俯冲带、北Sulawesi俯冲带、Halmahera俯冲带、New Britain俯冲带、Solomon俯冲带以及New Hebrides俯冲带等.但有关这些俯冲带的研究是相对独立的,对其进行系统的对比研究具有重要意义.文章主要回顾了关于西太平洋地区新近纪俯冲实例的起始模型研究,极性反转式的俯冲起始、诱发性的俯冲重起始以及形成新破裂的非继承性俯冲起始是其中较为典型的三类起始模型.另外,对其俯冲带参数进行汇编,俯冲带参数包括基本特征、俯冲板片特征、上覆板块特征、运动学特征以及俯冲后续活动五类.初步对俯冲过程的规律性、不同俯冲案例所体现出的特殊性以及俯冲起始类型与俯冲带参数特征之间可能存在的约束关系等进行讨论与分析.所汇编的俯冲带参数数据集可为相关研究提供数据支撑.

关键词：俯冲起始西太平洋新近纪俯冲带参数

应用固体探针质谱法测定流体包裹体气体成分及气体成分在矿化过程研究中的应用

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地质地球化学 1992年第1期20卷 55-60,46页

作者： j.Guha 卢焕章 m.Gagnon 栾文楼河北地质学院地质系

四极质谱仪能直接插入电离室的固体探针已用于流体包裹体的气相成分分析。这种探针可容纳一个能被连续加热或用可变的加热速率从30—750℃逐步加热的固体样品,爆裂的气体直接释放到光谱仪信号源中,因而可减少污染。分析应用了一个单离... 详细信息

四极质谱仪能直接插入电离室的固体探针已用于流体包裹体的气相成分分析。这种探针可容纳一个能被连续加热或用可变的加热速率从30—750℃逐步加热的固体样品,爆裂的气体直接释放到光谱仪信号源中,因而可减少污染。分析应用了一个单离子监测模式程序,这种程序可以分别地检测预选的26种气体,而且可应用这种方法分析Pg级的气体。应用面积求积仪检测并分别分析包裹体的每一个单一爆裂,计算机程序自动地查出背景值以上的基线。对于单一爆裂或不同温度区间的全部爆裂以及总区间之和,都计算了气体比值。应用常规岩相学和显微测温分析测定不同世代的包裹体及其爆裂温度,然后把含有典型流体包裹体或作分析靶的包裹体的两面抛光薄片的细片切下来,送到固体探针内并适当加热。已分析的主要气体化学形式有CO_2、CO-N_2(未区分)、H_2O、H_2S和几乎所有的轻烃类,还分析了不同主矿物,如石英、萤石、重晶石和硫化物中的流体包裹体。这种方法最重要的优点是,分析结果能与特定的包裹体类型相对应,因为只需要少量的样品,可使其从两面抛光的薄片上容易选择特定区域。另一个优点是,能够使石英的包裹体中存在的气相和与石英共生的硫化物中包裹体的气相相对应,因此可确认或否认这两种矿物捕获了相似的流体。

关键词：流体包裹体气体成分质谱法矿物

硅粉纯化水中病毒核酸在PCR方法中作用研究

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卫生研究 1996年第3期25卷 143-147页

作者：刘晶星 j.m.Seigneurin 上海第二医科大学微生物教研室上海200025 法国格勒诺布尔(Grenoble)第一大学医学院分子病毒室

利用纯腐殖酸制剂,人工制备了污染有脊髓灰质炎病毒、甲型肝炎病毒、轮状病毒及3种病毒混合的水样品,研究了腐殖酸对反转录和 PCR(RT-PCR)的抑制作用及硅粉的去抑制作用。结果显示当水中腐殖酸浓度大干或等于1g/l 时,3种病毒的 RT-PCR ... 详细信息

利用纯腐殖酸制剂,人工制备了污染有脊髓灰质炎病毒、甲型肝炎病毒、轮状病毒及3种病毒混合的水样品,研究了腐殖酸对反转录和 PCR(RT-PCR)的抑制作用及硅粉的去抑制作用。结果显示当水中腐殖酸浓度大干或等于1g/l 时,3种病毒的 RT-PCR 均被抑制,当浓度在10～100mg/l 之间,常规方法提取病毒 RNA、RT-PCR 阴性,而经硅粉纯化处理过的病毒 RNA、RT-PCR 阳性,硅粉能有效去除腐殖酸对 PCR 的抑制;当浓度等于或小于10mg/l RT-PCR 不受影响。结果还同时表明,用6-核苷酸代替病毒特异性引物成功地对混合病毒样品进行了反转录。

关键词：病毒核酸硅粉聚合酶链反应