查询词典 diffusion cloud chamber

Incurrent research, aiming at the rupture problem engendered in the shooting process of acertain 5.56mm automatic rifle, the strain and stress distributions on the cartridge caseunder the action of axial pull have been analyzed. Based on the theories of elastic-plasticmechanics and contact mechanics, a mathematic and physical model of the cartridge-caseand chamber system has been set up; and based on the platform of the general softwarepackage APDL of ANSYS for finite element analysis, a parameterized model of thecartridge-case and chamber system has also been established. The method for nonlinearFEA has been adopted to analyze the stress distribution on the entire cartridge-case andchamber system, and the method of contact element has been employed to investigate thecontact stress between the cartridge case and chamber, and then the influences of frictioncoefficient and locking space on the static and dynamic stress and strain response of thecartridge case and chamber to the action of power gas have also been discussed. On thebasis of a lot of numerical tests, a kind of element Plane13, which is concentrated incoupled computation of heat and construction, has been used finally to simulate thetransient response of the cartridge-case and chamber system to the power gas. Throughloading the temporary thermal characteristics of explosive gas in the procedure of emulate, the corresponding transient thermal stress distributed on the entire system under thecombined load of transient thermal stress and transient pressure has been obtained. Owingto these comprehensive considerations, the numerical results obtained in this paperrepresent the actual situations comparatively exactly.

本文针对某5.56mm自动步枪在工作中出现断壳的问题，分析了弹壳在轴向拉力作用下的应力应变；基于弹塑性力学及接触理论，建立了弹壳弹膛系统的数学、物理学模型，在通用有限元ANSYS软件的参数化建模工具APDL平台上，建立了弹壳弹膛系统的参数化模型；采用非线性有限元法计算了弹壳弹膛系统的整体应力，引入接触单元法分析弹壳和弹膛的接触压力，探讨了在不同的摩擦系数和不同的闭锁间隙对弹壳弹膛静、动态响应的影响；本文进行了大量的尝试，最后确定采用热、结构耦合单元Plane13，在计算中加载了火药气体的温度历程，成功的获得了弹壳弹膛系统在瞬态的热载荷和瞬态的压力载荷同时作用下弹壳弹膛系统的热应力数值解，考虑因素全面，比较真实的反映了弹壳弹膛系统在火药气体压力和热载荷下作用的情况。

To start the reaction , water fills a priming chamber and solution chamber of the primary vessel , the priming chamber being located in an upper portion of the primary vessel , and an air pump forces a predetermined portion of water from the priming chamber via a feed line through a grommet at the top of the canister to a chemical reaction chamber of the canister along with a continuous air flow .

开始反应，水充满初级室和初级反应器溶液室，初级室是安装在1级反应器上部，并用空气泵驱驶水由初级室管道供给线通过罐子顶部的环眼并随连续的空气流进入罐子的化学反应室。

Manufactures and markets test equipment products include: Programmable constant temperature and humidity testing machine, constant temperature and humidity box, high and low temperature testing machine, high-temperature box, cold temperature testing machine, hot and cold impact testing machine, the temperature cycling chamber, salt spray test machine, corrosion test chamber, the aging test machine, a large environmental test chamber, high temperature aging rooms, environmental test chamber, UV weathering test chamber, vibration, drop test machine, temperature water tank, clamshell laptop life testing machine, keyslife testing machine, testing machine drop life test simulation environment test equipment.

伟煌试验设备有限公司生产和销售的产品包括：可程式恒温恒湿试验机，恒温恒湿箱，高低温试验机，高低温箱，低温耐寒试验机，冷热冲击试验机，温度循环试验箱，盐水喷雾试验机，耐腐蚀试验箱，老化试验机，大型环境试验室，高温老化房，环境试验室，紫外线耐候试验箱，振动，跌落试验机，恒温水槽，笔记本翻盖寿命测试机，按键寿命测试机，跌落寿命测试试验机等模拟环境试验设备。

American International Chamber of Commerce of the United States Chamber of Commerce, the Pan Pacific is still the most active American International Chamber of Commerce, the most important independent divisions, continue to work with the United States with the International Chamber of Commerce plays a strong role for the United States to overseas members, particularly the Pan-Pacific Rim investment in business services, in promoting economic and trade exchanges with China have been well received by the International Chamber of Commerce and the United States from all walks of life admired and praised unanimously.

美国国际商会的美国泛太平洋商会至今仍是美国国际商会最活跃、最重要的独立分部，继续与美国国际商会一起发挥着强有力的作用，为美国会员提供前往海外、特别是泛太平洋沿岸国家的投资经商服务，在促进与中国的经贸交流得到了好评，受到美国国际商会与各界的一致推崇与赞誉。

His major works and commissions include: ' Three Temperaments , for Big Choir ' (1986), ' Counterpoint of Times , for woodwind septet ' (1989), ' Wild Children , for mixed Chamber Ensemble ' (1993), ' Overture , for solo Chinese bass drum and Chinese winds and percussion band ' (1994), ' Intonation , for chamber orchestra ' (1990-1994), ' Flavour of Bashu , for two violins, piano and percussion ' (1995), ' Pole , for solo Chinese Yun-luo, Chinese pai-gu and Chinese bass drum with six percussionists ' (1996),commissioned by Japan Asian Percussion Ensemble, ' Symphonic Prelude --- Bashu Capriccio' (1996), 'The Song Without Words , for solo percussion ' (1997), commissioned by the Ministry of Culture of Japan, Japanese Contemporary Music Association, and Japanese Embassy in China,'Illusions of the Symphonic Stage of Tang Dynast y , for orchestra of Tang Dynasty, percussion, voices and a big choir '(1999), commissioned by Japanese No Music Guanshiliu Green Spring Association, Chinese Music Research Center in Japan, Japanese Asian Percussion Ensemble and Japanese-Chinese Cultural Exchange Association,'The Prospect of Colored Desert , for violin, cello, sheng, pipa and percussion '(2000),commissioned by Yo-Yo Ma, Silk Road Project Inc. of the U.S., Sony Record,'Three Movements of Autumn , for small Chinese instruments ensembl e'(2000) and ' Sound Games , for 5 Chinese Percussion Instruments Players ' (2000-01), commissioned by La Cité de la Musique, Paris "2000 Chinese Classical Music Series", ' Fusion I , for Mixed Chamber Ensemble ' (2002), commissioned by Holland New Ensemble and Atlas Ensemble, ' Fusion II , Concerto for Solo Chinese Percussion and Orch.' (2002), commissioned by Japanese–Chinese Committee of Friendship and Public Music Performance, and ' Fusion III , for Irish flute, accordion, bodhran, Chinese sheng, zheng, Percussion and 13 Strings with Chamber Choir.' (2003-04), commissioned by China-Ireland Exchange Program, ' The Three Images from Washing Painting , for chamber ensemble of 17 players '(2005) commissioned by the New Juilliard Ensemble for the special concert of the Juilliard Centennial and sponsored by Asian Cultural Council and the Guggenheim Partnership and 'The Butterfly Dream', new 7 scenes Opera inspired by KUN QU' (2007) commissioned by the Contemporary Legend Theatre, Taiwan etc.

主要作品及委约包括：《三种气质，无伴奏合唱》(1986)、《时间的对位，木管七重奏》（1989）、《野娃子，混合室内乐队与童声》(1993)、《对话，男声独唱，女高音，童声合唱团，混声合唱团与混合乐队》(1993-94)、《序鼓，独奏中国大鼓、排鼓、云锣与中国民间吹打乐队》（1994）、《吟，室内交响乐》（1990-1994）、《蜀韵，两支小提琴、钢琴与打击乐》（1995）、《极，独奏中国云锣、大鼓、排鼓与六位打击乐演奏家》（1996）、《巴蜀随想，交响序曲》（1996）、《无词歌，打击乐独奏》（1997）（日本国文化厅、日本现代音乐协会、日本国驻中国领事馆等联合委约）、《梦的交响舞台，唐代乐队，打击乐，人声与合唱团》（1999）（日本能乐观世流绿泉会、日本中国音乐勉强会、日本亚洲打击乐团、日中文化交流协会等联合委约）、《舞蹈组曲，大型管弦乐队》(1999)、《漠墨图，小提琴、大提琴、笙、琵琶与打击乐》（2000）（马友友、美国丝绸之路文化发展公司、日本Sony唱片等联合委约）、《秋三阕，9位中国乐器演奏家》（2000）、《响趣，5位中国打击乐器演奏家》（2000）（法国巴黎音乐城&2000中国古典音乐系列音乐会&委约）、《融I ，混合室内乐团》（2002）（荷兰 New Ensemble， Atlas Ensemble联合委约）、《融II ，打击乐协奏曲》（2002）（日本日中友好音乐公演委员会委约）、《融III ，爱尔兰笛子、手风琴、巴朗鼓，中国笙、筝，打击乐，13件弦乐器以及室内合唱团》（2003-04）（爱尔兰国家文化委员会、爱中2004文化交流年组委会委约）、《水墨画意三则，为17位演奏家的室内乐团》（2005）（美国朱丽亚音乐学院新室内乐团委约，美国亚洲文化基金会和美国古根海姆基金支助）及《梦蝶，七场新昆剧》（2007）等。

A numerical calculation program is written up for the various solution methods in this paper and the program is being used in various aspects of inverse problem of environmental hydraulics, including inverse problem in reverse process of one-dimensional unstable diffusion, inverse problem in reverse process of convection-diffusion, inverse problem for the dispersion coefficient in water quality model, The inverse problem of coefficient identification for nonlinear Boussinesq equation, parameter identification inverse problem for water quality model, the inversion of parameter of BOD-DO water model, the inverse problem of the source of convection-diffusion, identification of the steady-state permeability for two dimensional isotropic medium, two-dimensional steady inverse problem of convection-diffusion and parameter identification inverse problem for two-dimensional parabolic equation, etc.

对本文提出的各种算法，编制了数值计算程序，并把它应用于环境水力学反问题诸多领域，包括污染物一维非恒定扩散逆过程反问题，对流扩散方程逆过程反问题，河流水质纵向弥散系数反问题，非线性Boussinesq方程反问题，河流水质多参数识别反问题，BOD-DO水质模型参数反演问题，对流—扩散方程源项反问题及二维恒定各向同性介质渗透系数反问题，二维定常对流——扩散方程及二维抛物型方程参数控制反问题等。

Diffusion problem of a predator-prey model with Holling typeⅡfunctional capturing function is studied. Stability condition is obtained when diffusion is absent, and the effect on stability of positive equilibrium is studied when diffusion is present. In the end, the problem of existence of limit cycle is proved in the first quadrant when diffusion is absent.

针对一类具有HollingⅡ型功能捕获函数的捕食－食饵模型的扩散问题进行了研究，得到了无扩散时正平衡点的稳定条件，以及扩散存在时对正平衡点稳定性产生的影响，最后证明了无扩散时系统在第一象限存在极限环的问题。

Assuming infinite diffusion medium, based on the diffusion equation for prestressed concrete structure, and accounting for the effects of concrete chloride binding capacity, time dependence of diffusion coefficients, temperature and moisture, models of chloride diffusion in two-dimensional infinite body with both power function and constant homogeneous boundary conditions were formulated.

针对无限大的扩散介质，以综合考虑氯离子结合能力、氯离子扩散系数的时间依赖性和环境温湿度影响的实际预应力混凝土氯离子方程为基础，分别在常数和幂函数边界条件下，推导出二维氯离子扩散理论的齐次模型。

This dissertation involves the study of the growth dynamics of colloidal particles under unequilibrium and irreversibility condition. Firstly, it is of interest to investigate whether the ideal diffusion or reaction-limited aggregation universal behavior can be observed for the initially polydisperse practical system of basic yttrium carbonate as well. The fractal structure of basic yttrium carbonate aggregate cluster was observed using transmission eletron microscopy. The aggregation kinetics of basic yttrium carbonate colloids was studed using dynamic 1ight-scattering techniques. At 1.00mol/l NaCl solution the fast diffusion-limited aggregation behavior was observed with an increase in the aggregate size over time described by a power law. The aggregates are characterized by a fractal dimension D=1.82. The disordered and ramified cluster is consisted of primary colloidal particles and tenuous and more open. These are in good agreement with those observed for other colloidal system such as colloidal gold (1.86), silica (1.85) and polystyrene latex (1.82) in diffusion-limited aggregation from the static and dynamic light scattering by Lin. Therefore ideal diffusion-limited aggregation behavior can be observed in practical polydisperse system as well. Smoluchwski and fractal theories were used to obtain the aggregation rate constant for initially polydisperse system for the first time.

本论文研究胶粒的非平衡不可逆聚集动态学，分为两个部分，第一部分是通过实验研究一个新的初始多分散的碱式碳酸钇胶粒实际体系中，聚集标度性质的普适性，即使用透射电子显微技术观测聚集粒子簇的分形结构，使用动态激光光散射研究碱式碳酸钇胶粒的聚集动力学，胶粒带电而产生静电排斥作用使得碱式碳酸钇胶粒处于稳定状态，当加入电解质NaCl溶液时，碱式碳酸钇胶粒间的Debye-Hückel屏蔽距离缩短，从而降低静电排斥能垒，引起胶粒发生不可逆聚集，加入电解质NaCl的浓度为1.00mol/l时，碱式碳酸钇胶粒进行快速聚集，经历扩散控制聚集机理，形成结构疏松、更为开放的分形聚集粒子簇，其分形维数为1.82，碱式碳酸钇胶粒聚集增长动力学遵循幂函数增长规律，与Lin等使用静态激光光散射和动态激光光散射测量硅胶(1.85)、金胶(1.86)和聚苯乙烯胶乳(1.82)在扩散控制聚集状态形成聚集粒子簇的分形维数值以及粒子簇聚集增长的动力学规律相一致，表明胶粒聚集标度性质的普适性质在初始多分散的实际体系中也是存在的，首次由动态激光光散射的实验数据得到初始多分散胶粒分形粒子簇的聚集速率常数，并且其值与Smoluchowski聚集速率理论预期相符。

In this paper,two nonlinear anisotropic diffusion filtering methods are presented and they are based on the multispectral anisotropic diffusion models proposed by Pope and Acton.We build a couple of new diffusion coefficients in partial derivative equation based on Tukey's biweight estimator error norm by recurring to the relationship between robust statistics and anisotropic diffusion incorporated with the nonlinear time-dependent cooling technique for gradient threshold.

在Pope和Acton提出的两个多光谱图像各向异性扩散滤波模型的基础上，通过各向异性扩散和稳健统计学的联系，建立了基于B iwe ight Estim ator误差模型的扩散系数，同时利用非线性退化技术对梯度阈值的改进，提出了两个基于各向异性扩散方程的非线性滤波方法。

The changes of the HAF after liver injury may be related to the volume of blood loss, the intraabdominal pressure and the pneumoperitoneum duration.

肝撞击伤伴失血后肝动脉血流量的变化与失血量、气腹压力以及气腹持续时间等有密切联系。

Reneging on our commitments to the world's poor cannot be an austerity measure, she said.

放弃我们给世界上的穷国的承诺不能成为一种紧缩措施。