检索结果-南通市图书馆

Axisymmetric Stagnation-Point Flow with a General Slip Boundary Condition over a Lubricated Surface

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 2012年第2期29卷 126-129页

作者： M.Sajid K.Mahmood Z.Abbas The Abdus Salam International Centre for Theoretical Physics Strada Costiera 1134014TriesteItaly Department of Mathematics Riphah International UniversityIslamabad 44000Pakistan Department of Mathematics The Islamia University of BahawalpurBahawalpurPakistan

We investigate the axisymmetric stagnation-point flow of a viscous fluid over a lubricated surface by imposing a generalized slip condition at the fluid-fluid *** power law non-Newtonian fluid is considered as a *** lubrication layer is thin and assumed to have a variable *** transformed nonlinear ordinary differential equation governing the flow is linearized using *** method of superposi-tion is adopted to convert the boundary value problem into an initial value problem and the solution is obtained numerically by using the fourth-order Runge-Kutta *** results are discussed to see the influence of pertinent *** limiting cases of Navier and no-slip boundary conditions are obtained as the special cases and found to be in excellent agreement with the existing results in the literature.

关键词： boundary ordinary assumed

Analysis of the Low-Lying Spectra of Five-Nucleon Systems

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 2000年第7期17卷 485-487页

作者： BAO Cheng-Guang Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion AcceleratorLanzhou 730000 Department of Physics Zhongshan UniversityGuangzhou 510275(mailing address)

The wavefunctions are decomposed into components. The inherent nodal structure and the stability of these components are investigated. It is assumed that the low-lying states would be dominated by the components without inherent nodal surfaces. Based on this assumption, the composition of the wave functions of the low-lying states of 5He has been suggested and the qualitative feature of the spectrum has been explained.

关键词： nodal assumed qualitative

Electronic correlation in nearly free electron metals with beyond-DFT methods

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

npj Computational Materials 2022年第1期8卷 1756-1762页

作者： Subhasish Mandal Kristjan Haule Karin M.Rabe David Vanderbilt Department of Physics and Astronomy West Virginia UniversityMorgantownWVUSA Department of Physics and Astronomy Rutgers UniversityPiscatawayNJUSA

For more than three decades,nearly free-electron elemental metals have been a topic of debate because the computed bandwidths are significantly wider in the local density approximation to density-functional theory(DFT)than indicated by angle-resolved photoemission(ARPES)***,we systematically investigate this using first principles calculations for alkali and alkaline-earth metals using DFT and various beyond-DFT methods such as meta-GGA,G0W0,hybrid functionals(YS-PBE0,B3LYP),and LDA+*** find that the static non-local exchange,as partly included in the hybrid functionals,significantly increase the bandwidths even compared to LDA,while the G0W0 bands are only slightly narrower than in *** agreement with the ARPES is best when the local approximation to the self-energy is used in the LDA+eDMFT *** infer that even moderately correlated systems with partially occupied s orbitals,which were assumed to approximate the uniform electron gas,are very well described in terms of short-range dynamical correlations that are only local to an atom.

关键词： metals assumed narrow

Model of Collisional Sheath in Spherical and Cylindrical Geometries for Plasma Source Ion Implantation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 1996年第2期13卷 117-120页

作者： WANG De-zhen YU Jiong GONG Ye The Key National Laboratory of Materials Modification by Three Beams and Department of PhysicsDalian University of TechnologyDalian 116024

A model is developed that describes the temporal evolution of the sheath during a pulse of high negative voltage applied to a spherical and cylindrical target in a plasma such as that present in plasma source ion implantation for the case in which the pressure of the neutraJ gas is large enough that the ion motion in the sheath can be assumed to be highly *** analytic expressions of the sheath expanding velocity are *** positions of the shea th edge as a function of time predicted by the model are in agreement with those obtained by Huid equations.

关键词： assumed implantation cylindrical

Analytical Solution of the Blast Wave Problem in a Non-Ideal Gas

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 2011年第11期28卷 152-154页

作者： L.P.Singh S.D.Ram D.B.Singh Department of Applied Mathematics Institute of TechnologyBanaras Hindu UniversityVaranasi-221005India

An analytical approach is used to construct the exact solution of the blast wave problem with generalized geometries in a non-ideal *** is assumed that the density ahead of the shock front varies according to a power of distance from the source of the blast ***,an analytical expression for the total energy in a non-ideal medium is derived.

关键词： wave analytical assumed

Investigation of role of cartilage surface polymer brush border in lubrication of biological joints

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Friction 2022年第1期10卷 110-127页

作者： JinJing LIAO David W.SMITH Saeed MIRAMINI Bruce S.GARDINER Lihai ZHANG Department of Infrastructure Engineering.The University of Melbourne.Victoria 3010 Australia Faculty of Engineering and Mathematical Sciences The University of Western AustraliaWA 6009Australia College of Science Health.Engineering and Education.Murdoch UniversityWA 6150Australia

Although experimental evidence has suggested that the polymer brush border(PBB)on the cartilage surface is important in regulating fluid permeability in the contact gap,the current theoretical understanding of joint lubrication is still *** address this research gap,a multiscale cartilage contact model that includes PBB,in particular its effect on the fluid permeability of the contact gap,is developed in this *** modeling is employed to estimate the permeability of the contact *** permeability is classified into two categories:For a gap size>1μm,the flow resistance is assumed to be dominated by the cartilage roughness;for gap sizeassumed to be dominated by the surface polymers extending beyond the collagen network of the articular *** gap sizes of less than 1μm,the gap permeability decreases exponentially with increasing aggrecan concentration,whereas the aggrecan concentration varies inversely with the gap ***,the gap permeability is employed in a macroscale cartilage contact model,in which both the contact gap space and articular cartilage are modeled as two interacting poroelastic *** fluid exchange between these two media is achieved by imposing pressure and normal flux continuity boundary *** model results suggest that PBB can substantially enhance cartilage lubrication by increasing the gap fluid load support(e.g.,by 26 times after a 20-min indentation compared with the test model without a PBB).Additionally,the fluid flow resistance of PBB sustains the cartilage interstitial fluid pressure for a relatively long period,and hence reduces the vertical deformation of the ***,it can be inferred that a reduction in the PBB thickness impairs cartilage lubrication ability.

关键词： assumed polymer hence

Magnetic Field Dissipation in Dense Molecular Clouds

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 1998年第3期15卷 200-202页

作者： MAO Xin-jie TONG Yi Astronomy Department Beijing Normal UniversityBeijing 100875

In dense molecular clouds the grains become the main charged *** the hydrogen gas density reaches as high as nH=10^(11)cm^(-3) and the grains are assumed to be small polycyclic aromatic hydrocarbons(PAHs),the lower hybrid drift instability develops,leading to the creation of anomalous electric conductivity,which makes the magnetic Reynold's number of the system R_(M)~1 indicating the dissipation of magnetic *** the gas density continues to go up and over10^(11)cm_(-3),the collision frequency between PAHs and gas particles becomes larger than the plasma frequency,resulting in the collision process being *** that case the magnetic field also dissipates because R_(M)~1 is still kept.

关键词： collision magnetic assumed

Sheath Criterion for a Collisional Electronegative Plasma Sheath in an Applied Magnetic Field

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 2011年第12期28卷 191-194页

作者： ZOU Xiu LIU Hui-Ping QIU Ming-Hui SUN Xiao-Hang School of Science Dalian Jiaotong UniversityDalian 116028 Department of Physics Mathematics and Physics Science Class Tsinghua UniversityBeijing 100084

The sheath criterion for a collisional electronegative plasma sheath in an applied magnetic field is *** is assumed that the system consists of hot electrons,hot negative ions and cold positive *** effect of an applied magnetic field on the sheath criterion is *** results reveal that the magnetic field has effects on both the upper and lower limits,which cause the range of the ion Mach number to *** addition,the numerical calculations of the electronegative plasma sheath are carried out to demonstrate the effects of sheath criterion on the characteristics of the sheath.

关键词： criterion Criterion assumed

Temperature Rise at the Edges of Dark Molecular Clouds

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 2000年第1期17卷 67-69页

作者： MAO Xin-Jie Astronomy Department Beijing Normal UniversityBeijing 100875 Chinese Academy of Sciences-Peking University Joint Beijing Astrophysical Center Peking UniversityBeijing 100871

Two-fluid magnetohydrodynamic equations are applied to dark molecular clouds that are composed of neutrals mixed with minor charged particles,weakly ionized gas *** result shows the temperatures are higher at the cloud edges than at their inner regions,the cause of which is that the cloud potential,released as clouds contract particularly at their edges,along with some dissipated rotational kinetic energy is converted into *** cloud contracting is due to the loss of the magnetic field that threads it through ambipolar ***,without the support of the magnetic and the centrifugal forces in the direction of the magnetic Held assumed to be parallel to the cloud rotating axis,the cloud collapses in that direction when its mass is over the Jeans mass.

关键词： rotating systems. assumed