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901.
A thixotropic recovery model has been developed that is based on consideration of the microstructural interactions that occur
between particles within a suspension particle network. The model is based on Smoluchowski coagulation rate theory, utilizing
second order kinetics to describe the thixotropic recovery behavior. The model is applied to Na-montmorillonite-based coal
tailings suspensions and is also shown to be applicable to brown coal and bauxite residue suspensions. The model describes
all the recovery data well, especially at intermediate to large recovery times. The recovery of the montmorillonite suspensions
at short times was faster than predicted, indicating the existence of additional factors in early-time structure development.
The discrepancy may have also been due to the highly anisotropic nature of the clay platelets. The recovery rate constant,
K
r
, increases with increasing solids concentration (for constant surface chemical conditions) as would be expected from the
basis of the model.
Received: 22 September 2000 Accepted: 16 March 2001 相似文献
902.
O. Yu. Dashkova 《Siberian Mathematical Journal》2008,49(6):1023-1033
Under study are the solvable nonabelian linear groups of infinite central dimension and sectional p-rank, p ≥ 0, in which all proper nonabelian subgroups of infinite sectional p-rank have finite central dimension. We describe the structure of the groups of this class. 相似文献
903.
Summary A survey is outlined of some of the normal-state crystal properties of high Tc oxides that have been calculated recently by atomistic lattice simulations. 相似文献
904.
In this paper, we propose an implicit higher-order compact (HOC) finite difference scheme for solving the two-dimensional (2D) unsteady Navier–Stokes (N–S) equations on nonuniform space grids. This temporally second-order accurate scheme which requires no transformation from the physical to the computational plane is at least third-order accurate in space, which has been demonstrated with numerical experiments. It efficiently captures both transient and steady-state solutions of the N–S equations with Dirichlet as well as Neumann boundary conditions. The proposed scheme is likely to be very useful for the computation of transient viscous flows involving free and wall bounded shear layers which invariably contain spatial scale variation. Numerical results are presented and compared with analytical as well as established numerical data. Excellent comparison is obtained in all the cases. 相似文献
905.
Finite groups of Lie type form the greater part of known finite simple groups. An important class of subgroups of finite groups
of Lie type are so-called reductive subgroups of maximal rank. These arise naturally as Levi factors of parabolic groups and
as centralizers of semisimple elements, and also as subgroups with maximal tori. Moreover, reductive groups of maximal rank
play an important part in inductive studies of subgroup structure of finite groups of Lie type. Yet a number of vital questions
dealing in the internal structure of such subgroups are still not settled. In particular, we know which quasisimple groups
may appear as central multipliers in the semisimple part of any reductive group of maximal rank, but we do not know how normalizers
of those quasisimple groups are structured. The present paper is devoted to tackling this problem.
Supported by RFBR (grant No. 05-01-00797) and by SB RAS (Young Researchers Support grant No. 29 and Integration project No.
2006.1.2).
__________
Translated from Algebra i Logika, Vol. 47, No. 1, pp. 3–30, January–February, 2008. 相似文献
906.
907.
M. Van Barel E. Van Camp N. Mastronardi 《Numerical Linear Algebra with Applications》2005,12(10):981-1000
Very recently, an algorithm, which reduces any symmetric matrix into a semiseparable one of semi‐ separability rank 1 by similar orthogonality transformations, has been proposed by Vandebril, Van Barel and Mastronardi. Partial execution of this algorithm computes a semiseparable matrix whose eigenvalues are the Ritz‐values obtained by the Lanczos' process applied to the original matrix. Also a kind of nested subspace iteration is performed at each step. In this paper, we generalize the above results and propose an algorithm to reduce any symmetric matrix into a similar block‐semiseparable one of semiseparability rank k, with k ∈ ?, by orthogonal similarity transformations. Also in this case partial execution of the algorithm computes a block‐semiseparable matrix whose eigenvalues are the Ritz‐values obtained by the block‐Lanczos' process with k starting vectors, applied to the original matrix. Subspace iteration is performed at each step as well. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
908.
Kang Ji Wang 《Applied Surface Science》2008,254(7):1981-1985
Deposition of HfO2 films on n-type 4H-SiC substrates by sol-gel spin-on coating technique has been performed and the physical and electrical characteristics of this film as a function of annealing temperature (550, 750, and 850 °C for 30 min) have been reported. The physical properties of the film have been characterized using a Filmetrics and X-ray diffractometer, while conduction atomic force microscope and semiconductor parameter analyzer were used for electrical characterization. Phase transformation has been revealed in the oxide as the annealing temperature changed. Refractive index, relative density, dielectric constant of the film, and oxide-semiconductor interface trap density have been extracted and related to the leakage current through the oxide. It has been recorded that, oxide annealed at 700 °C has demonstrated the lowest leakage current and the best oxide reliability. The reasons of these observations have been explained. 相似文献
909.
We computed the test rank of a free solvable Lie algebra of finite rank. 相似文献
910.
Qiaohua Yang 《Journal of Mathematical Analysis and Applications》2008,341(2):998-1006
Let G be a simple Lie group of real rank one and N be in the Iwasawa decomposition of G. We prove a refined version of the Sobolev inequality on N in presence of symmetry. 相似文献