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961.
The plastic deformation field near the horizontal surface of a half space of perfectly plastic material associated with an indenting rotating rigid tooth is studied using slip line theory. The tooth is one of many on a roll surface and indents first into the half-space material and then rotates about the roll center. A slip line field is proposed for the deforming plastic region and a solution scheme is outlined. The emphasis is on determining the shape of the deforming region, especially that of the free surface. The study has a potential application in roughness transfer in metal forming processing. 相似文献
962.
Hyperfine Interactions - Rotational J=1→J=0 transitions in muonic molecule, (3Heμd) J ++, in [(3Heμd)++,2e]–D and [(3Heμd)++,e]+–D collisions are considered. The... 相似文献
963.
A. V. Ivanchenko S. A. Gromilov S. M. Zemskova I. A. Baidina L. A. Glinskaya 《Foundations of Physics Letters》2002,15(1):554-558
A new mixed-ligand complex, Cd(S2CN(C4H9)2)2Phen, is synthesized and investigated by thermal, element, and IR analyses and by diffractometry of polycrystals (DRON-3M, CuKα radiation, Ni filter). The crystal structure was determined on a CAD-4 Enraf-Nonius automatic diffractometer (MoKα radiation, θ from 1.5 to 25?, 2325 nonzero independent reflections, 190 refined parameters, R = 0.036 for I > 2Σ(I)). Crystal data for C30H44CdN4S4 : a = 15.592(3), b = 22.724(5), c = 9.922(2) å, space group Pbcn, V = 3515.5(12) å3, Z = 4, M = 701.33, dcalc = 1.325 g/cm3. The structure involves monomeric molecules in which the cadmium atom has a distorted octahedral environment. 相似文献
964.
Time-resolved electron paramagnetic resonance (TREPR) experiments are reported on an α-hydroxy acetophenone in waterg-glycerol and ethanol-ethanediol mixtures over a viscosity range of 1–32 cP. The magnitude and viscosity dependence of the radical pair mechanism polarization is in good agreement with theory. The triplet mechanism polarization is found to increase with decreasing solvent polarity and this is ascribed to an increase in the α-cleavage rate constant. The liquid spectra are used to interpret TREPR spectra of the acetophenone in dry and wet cotton. In dry cotton anti-phase structure is seen and is due to some of the radical pairs being trapped in cages. The triplet and radical pair mechanism polarization shows that the acetophenone adsorbs to the apolar crystallite surface and releases radicals into the polar amorphous regions where they experience a microviscosity of approximately 30 cP. In wet cotton there are no cages and the viscosity is greater than in ethanol alone. 相似文献
965.
J.T. Devaraju B.H. Sharmila S. Asokan K.V. Acharya 《Applied Physics A: Materials Science & Processing》2002,75(4):515-518
The electrical switching behaviour of As45Te55-xInx (5≤x≤15) and As50Te50-xInx (2.5≤x≤11.5) has been studied over a wide range of compositions. These glasses are found to exhibit threshold switching.
The composition dependence of switching voltage (Vt) has been found to exhibit a change in slope and a local minimum at compositions x=10 and 12.5 for As45Te55-xInx and x=7.5 and 10.8 for As50Te50-xInx, respectively. The slope change in Vt verses x and the local minimum have been identified using two network topological effects, namely the rigidity percolation
threshold and the chemical threshold.
Received: 23 August 2001 / Accepted: 27 August 2001 / Published online: 11 February 2002 相似文献
966.
R. Martínez-Snchez J. A. Matutes-Aquino O. Ayala-Valenzuela S. D. De la Torre 《Physica B: Condensed Matter》2002,320(1-4):285-287
An amorphous phase containing traces of non-transformed Co and Ti powders was obtained by mechanical alloying nominal compositions of Co67Ti33 and Co50Ti50 in a high-energy ball-mill. These alloys were prepared from elemental powders of Co and Ti. The heat treatment of Co67Ti33 at 573, 873 and 1173 K crystallized nanoparticles of Co2Ti and Co3Ti compounds, while the same treatments conducted on Co50Ti50 resulted in the formation of Co2Ti and CoTi nanoparticles. The saturation magnetizations reached a maximum value in the amorphous state and they decreased when the temperatures of the heat treatment rose. Demagnetizing interparticle interaction effects were estimated through hysteresis loops and initial magnetization curves using the Fourier technique. 相似文献
967.
Yu. G. Abov A. D. Gul'ko F. S. Dzheparov S. V. Stepanov S. S. Trostin 《Physics of Atomic Nuclei》2002,65(11):1999-2008
The nuclear magnetic resonance in beta-active nuclei 8Li at the doubled Larmor frequency in LiF polycrystals is studied before and after treating these polycrystals with an external pressure. A quantitative approach is proposed that makes it possible to calculate the parameters of the resonance line-shape function versus the dislocation structure of crystallites. Data suggesting that the samples under investigation that were subjected to a treatment with an external pressure develop dislocations whose Burgers vectors are parallel are obtained. 相似文献
968.
A classification has been obtained for spaces which admit complete sets of motion integrals of the (3.1)-type and are spatially homogeneous. The metrics and Killing vectors have been found in explicit form for all types of these spaces. A classification by Bianchi is given for the spaces obtained. 相似文献
969.
An electrostatic interaction between two separate, grounded, uncharged, perfectly conducting spheres of different radii in a uniform electrostatic field is investigated. It is shown that at a small center-to-center distance of the spheres, the force of the polarization interaction between the spheres depends appreciably more weakly on that distance in comparison to the force of the electrostatic interaction of two elementary dipoles as it should be in view of the interaction between two like polarization charges. 相似文献
970.
The Fokker–Planck-type kinetic equation is constructed with the help of the evolution equation for the transverse energy of channelized particles, which in its turn is derived beyond the framework of perturbation theory proceeding from the condition of nonconcervation of the adiabatic invariant. 相似文献