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951.
952.
The relativistic consistent angular-momentum projected shell model(ReCAPS) is used in the study of the structure and electromagnetic transitions of the low-lying states in the N=Z nucleus 52Fe.The model calculations show a reasonably good agreement with the data.The backbending at 12+ is reproduced and the energy level structure suggests that neutron-proton interactions play important roles. 相似文献
953.
Sun Zongjian 《Fiber and Integrated Optics》2013,32(4):327-331
We report on the use of a prism-fiber coupler to determine the propagation constants for the scalar modes in an optical fiber by measuring, respectively, the incident angle, θi, and the position of the m-lines coupled out of the fiber by the prism coupler. The position is related to the value of the corresponding propagation constant. The degeneracy of the modes is shown on the m-line photographs. Good agreement is obtained between measured and calculated values of the propagation constants. 相似文献
954.
C. Bekh-Ochir 《代数通讯》2013,41(8):2697-2706
We describe the T-ideal of identities and the T-space of central polynomials for the unitary finite dimensional Grassmann algebra over a finite field. 相似文献
955.
《Journal of computational and graphical statistics》2013,22(1):155-167
In an earlier article, Ghosh derived the density for the distance between two points uniformly and independently distributed in a rectangle. This article extends that work to include the case where the two points lie in two different rectangles in a lattice. This density allows one to find the expected value of certain functions of this distance between rectangles analytically or by one-dimensional numerical integration.In the case of isotropic spatial models or spatial models with geometric anisotropy terms for agricultural experiments one can use these theoretical results to compute the covariance between the yields in different rectangular plots. As the numerical integration is one-dimensional these results are computed quickly and accurately. The types of covariance functions used come from the Matérn and power families of processes. Analytic results are derived for the de Wijs process, a member of both families and for the power models also.Software in R is available. Examples of the code are given for fitting spatial models to the Fairfield Smith data. Other methods for the estimation of the covariance matrices are discussed and their pros and cons are outlined. 相似文献
956.
LIU Hui HOU De-Fu LI Jia-Rong 《理论物理通讯》2008,50(8):429-436
Within the framework of finite temperature field theory this paper discusses the shear viscosity of hot QED plasma through Kubo formula at one-loop skeleton diagram level with a finite chemical potential. The effective widths (damping rates) are introduced to regulate the pinch singularities and then gives a reliable estimation of the shear viscous coefficient. The finite chemical potential contributes positively compared to the pure temperature case. The result agrees with that from the kinetics theory qualitatively. 相似文献
957.
Electron cyclotron plasma reactor are prone to instabilities in specific input power [3–7] region (150–450 watts). In this
region power absorption by gas molecules in the cavity is very poor and enhanced input power gets reflected substantially
without increasing ion density. There are abrupt changes in plasma characteristics when input power was decreased from maximum
to minimum, it was observed that reflected power changed from <2% to ∼50%. Minimum two jumps in reflected power were noticed
in this specific power region and these appear to be highly sensitive to three stub tuner position in the waveguide for this
particular input power zone. Unstable plasma region of this source is found to be dependent upon the magnetic field strength.
Some changes in reflected power are also noticed with pressure, flow and bias and they are random in nature. 相似文献
958.
The present paper investigates the multigrid (MG) acceleration of compressible Reynolds‐averaged Navier–Stokes computations using Reynolds‐stress model 7‐equation turbulence closures, as well as lower‐level 2‐equation models. The basic single‐grid SG algorithm combines upwind‐biased discretization with a subiterative local‐dual‐time‐stepping time‐integration procedure. MG acceleration, using characteristic MG restriction and prolongation operators, is applied on meanflow variables only (MF–MG), turbulence variables being simply injected onto coarser grids. A previously developed non‐time‐consistent (for steady flows) full‐approximation‐multigrid (s–MG) is assessed for 3‐D anisotropy‐driven and/or separated flows, which are dominated by the convergence of turbulence variables. Even for these difficult test cases CPU‐speed‐ups rCPUSUP∈[3, 5] are obtained. Alternative, potentially time‐consistent approaches (unsteady u–MG), where MG acceleration is applied at each subiteration, are also examined, using different subiterative strategies, MG cycles, and turbulence models. For 2‐D shock wave/turbulent boundary layer interaction, the fastest s–MG approach, with a V(2, 0) sawtooth cycle, systematically yields CPU‐speed‐ups of 5±½, quasi‐independent of the particular turbulence closure used. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
959.
Grainger Reid J. Ko Samuel Koslov Eugene Prokop Ales Tanner Robert D. Loha Veara 《Applied biochemistry and biotechnology》2000,84(1-9):761-768
Human insulin in zinc suspension was used as a model protein to test the effect of shear on the settling rate of proteins,
a possible inference for protein denaturation. The rate of settling was determined directly in a spectropho-tometer. Shear
effects are important in retaining the activity of proteins and are present in bubble, foam, and droplet protein fractionation
processes. A sim pletest, such as that conducted here, mayeven be useful for monitoring changes in protein structure caused
by commercial shipping of the protein. The settling ratefor insulin was continously monitored in theoriginal bottle by spectrophotometric
absorbance changes as a function of time. A settling curve was determined following each shear experiment, which included
shaking the “worked” insulin solution in a vortex mixer for different lengths of time. It was determined, when comparing long
shaking times with short ones, that the initial settling rate was less for the long-term shaking of the insulin samples and
greater for the short-term shaking. The secondary effects of light and heat, along with shaking, a pparently did not produce
differences from shaking alone. 相似文献
960.
本文建立了若干新的具最佳常数因子的p进制Hardy-Littlewood-Pólya型不等式,同时也给出了它们的等价形式以及一些特殊结果. 相似文献