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粘弹性流体流经竖直表面时的瞬时自然对流

应用数学和力学 2010年第5期31卷 526-532页

作者： H·M·杜威瑞 r·A·丹赛 A·j·千姆克哈 M·S·艾伯德尔-亚博黄雅意(译) 张禄坤(校) 约旦大学工程技术学院机械工程系安曼11942约旦基地拜勒加应用大学基地胡森学院机械工程系伊尔比德21510约旦应用教育与培训公共管理局制造工程系舒韦赫70654科威特约旦大学工程技术学院土木工程系安曼11942约旦不详

静止流体中,在一个竖直的、不可渗透的等温表面附近,研究粘弹性边界层的流动及其热传导.得到其控制方程,并利用MackCormak技术对其进行数值求解.与先前发表的关于该问题特例的结果相比较,有着很好的一致性.对于不同的粘弹性参数值,图示... 详细信息

静止流体中,在一个竖直的、不可渗透的等温表面附近,研究粘弹性边界层的流动及其热传导.得到其控制方程,并利用MackCormak技术对其进行数值求解.与先前发表的关于该问题特例的结果相比较,有着很好的一致性.对于不同的粘弹性参数值,图示了速度和温度分布、边界层厚度、Nusselt数、局部摩擦因数等典型结果.一般而言,粘弹性流体与newton流体相比较,由于拉应力的促进作用,流体动力边界层里的速度是增加的,热边界层里的温度是下降的.粘弹性参数值越高,摩擦因数和传热系数越高.

关键词：粘弹性流动瞬时自然对流传热

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Nonlinear Waves in Solid Continua with Finite Deformation

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American journal of Computational Mathematics 2015年第3期5卷 345-386页

作者： K. S. Surana j. Knight j. N. reddy Department of Mechanical Engineering University of Kansas Lawrence KS USA Department of Mechanical Engineering Texas A & M University College Station TX USA

This work considers initiation of nonlinear waves, their propagation, reflection, and their interactions in thermoelastic solids and thermoviscoelastic solids with and without memory. The conservation and balance laws constituting the mathematical models as well as the constitutive theories are derived for finite deformation and finite strain using second Piola-Kirchoff stress tensor and Green’s strain tensor and their material derivatives [1]. Fourier heat conduction law with constant conductivity is used as the constitutive theory for heat vector. Numerical studies are performed using space-time variationally consistent finite element formulations derived using space-time residual functionals and the non-linear equations resulting from the first variation of the residual functional are solved using newton’s Linear Method with line search. Space-time local approximations are considered in higher order scalar product spaces that permit desired order of global differentiability in space and time. Computed results for non-linear wave propagation, reflection, and interaction are compared with linear wave propagation to demonstrate significant differences between the two, the importance of the nonlinear wave propagation over linear wave propagation as well as to illustrate the meritorious features of the mathematical models and the space-time variationally consistent space-time finite element process with time marching in obtaining the numerical solutions of the evolutions.

关键词： Linear and Nonlinear Waves Second Piola-Kirchoff Stress Green's Strain Constitutive Theories Dissipation Memory rheology Finite Strain

Universal soldier： Pseudomonas aeruginosa -- an opportunistic generalist

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Frontiers in Biology 2013年第4期8卷 387-394页

作者： jeremy GrOSS Ian j. PASSMOrE jade C. S. CHUNG Olena rZHEPISHEVSKA Madeleine rAMSTEDT Martin WELCH Department of Biochemistry University of Cambridge Cambridge CB2 1QW UK Department of Chemistry Umed University Umed 901 87 Sweden

The opportunistic pathogen Pseudomonas aeruginosa commonly causes chronic and ultimately deadly lung infections in individuals with the genetic disease cystic fibrosis （CF）. P. aeruginosa is metabolically diverse; it displays a remarkable ability to adapt to and successfully occupy almost any niche, including the ecologically complex CF lung. These P. aeruginosa lung infections are a fascinating example of microbial evolution within a ＂natural＂ ecosystem. Initially, P. aeruginosa shares the lung niche with a plethora of other microorganisms and is vulnerable to antibiotic challenges. Over time, adaptive evolution leads to certain commonly-observed phenotypic changes within the P. aeruginosa population, some of which render it resistant to antibiotics and apparently help it to out-compete the other species that co-habit the airways. Improving genomics techniques continue to elucidate the evolutionary mechanisms of P. aeruginosa within the CF lung and will hopefully identify new vulnerabilities in this robust and versatile pathogen.

关键词： Pseudomonas aeruginosa cystic fibrosis evolution adaptive radiation antibiotic resistance quorum sensing

EXACT CALCULATION METHODS OF INTErLINKED COLUMN SYSTEM——SIMULATION OF rECOVErY OF PHENOL FrOM WASTE WATEr CONTAINING PHENOL

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Chinese journal of Chemical Engineering 1986年第1期 95-106页

作者：许恩锡 j.W.TIErNEY Tianjin University University of Pittsburgh

This paper describes a mathematical model and an algorithm which can be used for simulation of in-terlinked column systems consisting of liquid-liquid extraction and *** algorithm is basedupon newton-raphson iteration technique using suitable damping factors and solutions of simplified modelas initial values of exact *** the exception of principle specification it is possible to interchangethe iteration variables and/or noniteration variables with design variables to meet requirements of design.A process of recovery of phenol from waste water containing pheonol is illustrated to varify the model *** results are satisfied.

关键词： EXACT CALCULATION METHODS OF INTErLINKED COLUMN SYSTEM SIMULATION OF rECOVErY OF PHENOL FrOM WASTE WATEr CONTAINING PHENOL

Mass as the Fifth Dimension of the Universe

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International journal of Astronomy and Astrophysics 2013年第3期3卷 257-259页

作者： Bijan Nikouravan jitendra j. rawal Department of Physics Islamic Azad University (IAU)-Varamin-Pishva Branch Tehran Iran Department of Physics University Malaya (UM) Kuala Lumpur Malaysia

newton considered three-dimensional universe endowed with flat space Euclidean geometry, and treated the time as an outside parameter and established his dynamics of the universe. Einstein along with space, considered time, and generated a four-dimensional universe endowed with non-Euclidean curved space-time geometry with time as its fourth dimension, and set up his field equations. Schwarzschild solved Einstein’s field equations around a star in space, which is, otherwise, flat, and obtained a solution. We, along with space and time, considered mass which also included energy according to Einstein’s mass-energy equivalence relation: E = mc2, and generated a five-dimensional universe with the mass as its fifth dimension, and solved the Einstein’s field equations, in some simple cases, and obtained solutions around a star in space, which is otherwise, flat.

关键词： Mass 5D Universe Einstein’s Field Equations

Nature’s Particulate Matter with and without Charge and Travelling

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Open journal of Biophysics 2016年第3期6卷 75-82页

作者： Bob W. N. j. Ursem Department of Biotechnology Faculty of Applied Sciences Botanic Garden Delft University of Technology Delft The Netherlands

Natures and anthropogenic particulates can travel long distances on wind flows, but negative electrical charge due to friction can increase dispersion. Models for calculations of distance travelling of biological particulate matter with and without charge are never been calculated in a theoretical approach. Nor do we realize the fact that we can calculate actual distances if we take the charge on particles in account. Particles that travel through the air encounter friction. Friction can be described in two ways;either in a smooth constant way through the air with its viscous forces, or in a turbulent chaotic eddies and vortices and other flow instabilities. In case of only viscous forces are to be concerned, it can be described as a lower reynolds number than one, while in all other setting it always must be described by reynolds numbers larger than or equal to one. This article describes the calculated effects on particles, either in a low reynolds number and thus as a Navier-Stokes equation or Stokes’ Law or, in case of non-laminar and complex forces in an equal or higher reynolds number according to the third Law of newton. In addition some striking examples of particle travelling are given with evidence of natural particulate matter long distance dispersion.

关键词： Natural Dispersion Electrical Charge Stokes newton

Thermal Physics and Statistical Mechanics Driven Inertial Confinement Fusion(ICF)Inducing a Controlled Thermonuclear Energy

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journal of Energy and Power Engineering 2021年第1期15卷 20-38页

作者： Bahman Zohuri Farahnaz Behgounia Masoud j.Moghaddam Golden Gate University Ageno School of BusinessSan FranciscoCalifornia 94105USA Galaxy Advanced Engineering AlbuquerqueNew Mexico 87111USA

In the 1970s,scientists began experimenting with powerful laser beams to compress and heat the hydrogen isotopes to the point of fusion,a technique called ICF(Inertial Confinement Fusion).In the“direct drive”approach to ICF,powerful beams of laser light are focused on a small spherical pellet containing micrograms of deuterium and *** rapid heating caused by the laser“driver”makes the outer layer of the target *** keeping with Isaac newton’s Third Law“For every action,there is an equal and opposite reaction”,the remaining portion of the target is driven inwards in a rocket-like implosion,causing compression of the fuel inside the capsule and the formation of a shock wave,which further heats the fuel in the very center and results in a self-sustaining *** fusion burn propagates outward through the cooler,outer regions of the capsule much more rapidly than the capsule can *** of magnetic fields,the plasma is confined by the inertia of its own mass—hence the term inertial confinement fusion.A similar process can be observed on an astrophysical scale in stars and the terrestrial uber world,that have exhausted their nuclear fuel,hence inertially or gravitationally collapsing and generating a supernova explosion,where the results can easily be converted to induction of energy in control forms for a peaceful purpose(i.e.,inertial fusion reaction)by means of thermal physics and statistical mechanics behavior of an ideal Fermi gas,utilizing Fermi-Degeneracy and Thomas-Fermi *** fundamental understanding of thermal physics and statistical mechanics enables us to have a better understanding of Fermi-Degeneracy as well as Thomas-Fermi theory of ideal gas,which results in laser compressing matter to a super high density for purpose of producing thermonuclear energy in way of controlled form for peaceful shape and form ***(Controlled Thermonuclear reaction).In this short review,we have concentrated on Fundamental of State Equations by dri

关键词： renewable nonrenewable source of energy fusion reactors super high density matter laser driven fusion energy Fermi-Degeneracy Thomas-Fermi theory return on investment total cost of ownership

A Molecular Dynamics Approach for Optimizing Beam Intensities in IMPT Treatment Planning

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journal of Applied Mathematics and Physics 2019年第9期7卷 2130-2047页

作者： Li Liao Gino j. Lim Xiaodong Zhang Department of Industrial Engineering University of Houston Houston TX USA Department of radiation Physics The University of Texas MD Anderson Cancer Center Houston TX USA

This paper uses a molecular dynamics (MD) method for intensity-modulated proton therapy treatment planning optimization to overcome the problem of gradient-based optimization methods such as quasi-newton, which is sensitive to starting conditions and is easily trapped in local minima. We implemented a molecular dynamics (MD) method and a quasi-newton method for plan optimization. Three types of cancer cases, prostate, head-and-neck and lung cancer, were tested with three starting different initial conditions. Overall, the MD method consistently resulted in solutions with lower objective function values (OFVs) compared to those from the quasi-newton algorithm. Furthermore, the MD method converged on the same OFV regardless of its initial starting points used for the prostate cancer case.

关键词： Molecular Dynamics Intensity-Modulated Proton Therapy Quasi-newton

白细胞介素-1受体-1基因的功能多态性与幽门螺杆菌的感染率增高有关,与胃癌无关

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世界核心医学期刊文摘（胃肠病学分册） 2005年第2期1卷 9-9页

作者： Hartland S. newton j.L. Griffin S.M. Donaldson P.T. 郝筱倩

The proinflammatory cytokine interleukin-1 has been implicated in host suscep tibility to Helicobacter pylori -associated disease. recent studies suggest tha t this susceptibility may be under genetic control. It remains to be determined whether the relationship between IL-1 gene polymorphism and gastrointestinal di sease in patients with H. pylori infection is due to the role of IL-1 in determ ining susceptibility to H. pylori infection per se or to the development of dist inct pathological lesions. The aim of this study was to prospectively investigat e the relationship between selected polymorphisms in three of the major IL-1 ge ne family members, seeking associations with H. pylori infection and/or gastric cancer. A total of 559 individuals were studied: 191 patients attending for gast roscopy, 98 with current or previous H. pylori, an additional 79 patients with g astric cancer, and 289 healthy controls. The major novel finding of the study wa s a marked difference in the genotype frequencies for the IL1r1 HinfI SNP in tho se with current or previous evidence of H. pylori compared to those without. (GG , 53 vs 75%; GA, 40 vs 19%; AA, 7 vs 6%; P = 0.0079). The association indicat es an increased risk of H. pylori infection or persistence in those with the IL1 r1 Hinf1 A allele (0.27 vs 0.156; P = 0.009; Or = 2.01). Our results suggest tha t the relationship among IL-1 gene polymorphism, H. pylori, and disease is more complex than initially proposed. More detailed studies of the IL-1 gene cluste r are needed.

关键词：白细胞介素多态性病理损伤胃镜检查促炎因子染易胃肠疾病感染期遗传控制胃肠病

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