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921.
J.-M. Hofman-Züter K. Keizer H. Verweij A.J. Burggraaf 《Journal of Sol-Gel Science and Technology》1997,8(1-3):523-527
For improving chemical and thermal stability of γ-Al2O3 membranes boehmite (AlOOH) sol-particles are coated with Zr4+-species with two techniques. These techniques are heterogeneous precipitation (HP-method) and “surface-reaction-followed-by-polycondensation”
(SRPC-method). A continuous coating layer is formed at relative low Zr4+-concentration, about one monolayer coverage of boehmite particles, and with the HP-method. For large concentrations and for
the SRPC-method small particles (order 1 nm) of Zr4+-species are formed on the surface of the boehmite particles. After drying and calcination up to 1000°C no continuous layer
of a zirconia phase could be detected for all samples. However the thermal stability of the porous structure is improved.
Phase transitions of alumina occur at temperatures of 1100°C and the porous structure of the membrane material is then destabilized. 相似文献
922.
在定粒缫丝工程中采用粗细茧丝搭配的方法进行配茧缫丝时,需要根据落绪茧及茧丝粗细搭配状况选择适当的接绪茧接绪,以保持厚薄茧型的搭配,减小生丝纤度方差.本文对该缫丝动态过程进行数学建模,给出差微分方程组及其平衡状态下不同茧层茧粒数的分布.通过对定粒缫丝动态过程的计算机模拟,对获得的理论结果及其在缫丝工程管理中的应用问题进行了讨论. 相似文献
923.
本文研究了具有混合光滑性的Holder-Nikolskii-Wiener类SrpqH在Lq(Rd)中的平均σ-K宽度(2≤q≤p<∞),得到了该量的弱渐近估计. 相似文献
924.
A branch-and-bound algorithm to solve 0–1 parametric mixed integer linear programming problems has been developed. The present algorithm is an extension of the branch-and-bound algorithm for parametric analysis on pure integer programming. The characteristic of the present method is that optimal solutions for all values of the parameter can be obtained. 相似文献
925.
With a view to study the pre-equilibrium effects in neutron-induced reactions, the activation cross-sections for (n, 2n) reactions at 14.2±0.2 MeV in the heavy mass region have been measured using the versatile mixed powder technique and high
resolution Ge(Li) detection. The experimental cross-sections are found to be consistently smaller than the predictions based
on the statistical theory and this is attributed to the effect of pre-equilibrium decay in these reactions. The cross-sections
due to pre-equilibrium decay were estimated using exciton, hybrid and unified models. When this cross-section was included
in comparing the experimental cross-sections with theory, we obtained better agreement, within the limitations of the present-day
preequilibrium theories.
Preliminary results of this work were reported at the Nuclear Physics and Solid State Physics Symposium, Pune (1978). 相似文献
926.
M D Srinivas 《Pramana》1982,19(2):159-173
This paper is devoted to a study of some of the basic conditions which have to be satisfied by a hidden variable theory in
order that it can reproduce the quantum mechanical probabilities. Of course one such condition, which emerges from the important
theorem of Bell, is that a hidden variable theory has to be non-local. It is shown that a hidden variable theory is also incompatible
with the conventional interpretation of mixed states and the mixing operation in quantum theory. It is therefore concluded
that, apart from being non-local, a hidden variable theory would also necessarily violate the usual assumption of quantum
theory that the density operator provides an adequate characterization of any ensemble of systems, pure or mixed. 相似文献
927.
928.
The application of a Fourier spectrometer to the study of the electronic structure in the far infrared of some intermediate valence or heavy fermion materials or of highT
c
superconductors showed that FT-reflectivity is a powerful tool of investigation at very low energies. A very careful control of the experimental conditions and of the reference measurements is necessary to eliminate spurious reflectivities.The results show optical transitions at very low energy and permit to evaluate the electronic structures and the effective mass of the carriers in the vicinity of the Fermi level. 相似文献
929.
The transient response mechanism of the platinum electrode to the uncoupled ions may be interpreted with the mixed phase formation (MPF) model of the transient response of precipitate-based ion-selective electrodes to interfering tons for Kxy<<1 It is discovered that the peak height of the transient signal is related to the solubility of M(OH)2 and hydration heat of M2+ The relation between the positive peak height of transient signal of Pb2+ or Cd2+ and lgaM obey tne Nernst equation,while that of Ca2+ or Mg2+ does not.The equilibrium potential is not of Nernst response for all ions. 相似文献
930.
On the extended linear complementarity problem 总被引:8,自引:0,他引:8
M. Seetharama Gowda 《Mathematical Programming》1996,72(1):33-50
For the extended linear complementarity problem (Mangasarian and Pang, 1995), we introduce and characterize column-sufficiency,
row-sufficiency andP-properties. These properties are then specialized to the vertical, horizontal and mixed linear complementarity problems.
This paper is dedicated to Professor Olvi L. Mangasarian on the occasion of his 60th birthday. 相似文献