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531.
This paper presents an exact solution for steady-state conduction heat transfer in cylindrical composite laminates. This laminate
is cylindrical shape and in each lamina, fibers have been wound around the cylinder. In this article heat transfer in composite
laminates is being investigated, by using separation of variables method and an analytical relation for temperature distribution
in these laminates has been obtained under specific boundary conditions. Also Fourier coefficients in each layer obtain by
solving set of equations that related to thermal boundary layer conditions at inside and outside of the cylinder also thermal
continuity and heat flux continuity between each layer is considered. In this research LU factorization method has been used to solve the set of equations. 相似文献
532.
In this paper, an analysis of kinematics of the isotropic elastic Cosserat continuum is presented in infinitesimal and finite deformations. Emphasis is given on the applicability of corotational stress rates for hypoelasticity in micro-polar continua. A non-linear finite element analysis is performed with an explicit formulation of tangent stiffness matrices in the case of Truesdell stress and couple stress rates. A comprehensive path-dependent procedure is employed based on the arc-length method to calculate the stability points and handle the snap-back problem. Finally, the accuracy and efficiency of method are illustrated by numerical examples. 相似文献
533.
Azizian J Mohammadi AA Karimi AR Mohammadizadeh MR 《The Journal of organic chemistry》2005,70(1):350-352
KAl(SO(4))(2).12H(2)O is found to catalyze efficiently the stereoselective one-pot three-component cyclocondensation of homophthalic anhydride, aldehydes, and amines under mild conditions to afford the corresponding cis-isoquinolonic acids in good yields. 相似文献
534.
[reaction: see text] A new silica-based scandium(III) interphase catalyst 2 efficiently catalyzes the cyanosilylation of a variety of aldehydes and ketones. The catalyst shows high thermal stability (up to 300 degrees C) and also is stable in both organic and polar solvents. It also could be recovered and reused for at least 10 reaction cycles without considerable loss of reactivity. 相似文献
535.
We study type II supernova signatures of neutrino mass generation via symmetry breaking at a scale in the range from keV to MeV. The scalar responsible for symmetry breaking is thermalized in the supernova core and restores the symmetry. The neutrinos from scalar decays have about half the average energy of thermal neutrinos. The Bose-Einstein distribution of the scalars can be established with a megaton water Cerenkov detector. The discovery of the bimodal neutrino flux is, however, well within the reach of the Super-Kamiokande detector, without a detailed knowledge of the supernova parameters. 相似文献
536.
537.
M.R. Hooshmandasl A. Karimi M. Almbardar B. Davvaz 《International Journal of Approximate Reasoning》2013,54(2):297-306
Axiomatic approaches to study approximation operators are one of the primary directions for the investigation of rough set theory. In this paper, we provide some axiomatic systems of lower and upper approximation operators in rough set theory. We also apply the axiomatic systems of generalized rough sets for definitions of generalized lower and upper approximations with respect to an ideal of a ring and discuss some of their significant properties. 相似文献
538.
The present work has focused on the modification of multiwalled carbon nanotube with a ligand,l-(2-pyridylazo)-2-naphthol, and its potential application for the development of a new,simple and selective modified glassy carbon electrode for stripping voltammetric determination of Cd(Ⅱ).The analytical curve for Cd(Ⅱ) ions covered the linear range varying from 0.8 up to 220.4μgL-1.The limit of detection was found to be 0.1μgL-1,while the relative standard deviation(RSD) at 50.0μgL-1 was 1.8%(n=5).This modified electrode was successfully applied for determination of Cd(Ⅱ) in some water samples. 相似文献
539.
N‐(3,4‐dihydroxyphenethyl)‐3,5‐dinitrobenzamide modified multiwall carbon nanotubes paste electrode was used as a voltammetric sensor for oxidation of penicillamine (PA), uric acid (UA) and tryptophan (TP). In a mixture of PA, UA and TP, those voltammograms were well separated from each other with potential differences of 300, 610, and 310 mV, respectively. The peak currents were linearly dependent on PA, UA and TP concentrations in the range of 0.05–300, 5–420, and 1.0–400 µmol L?1, with detection limits of 0.021, 2.0, and 0.82 µmol L?1, respectively. The modified electrode was used for the determination of those compounds in real samples. 相似文献
540.