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91.
I. Waclawska 《Journal of Thermal Analysis and Calorimetry》1997,48(1):145-154
The effect of mechanical treatment on the thermal decomposition of calcium borate, colemanite — Ca2B6O8(OH)6·2H2O was studied by means of XRD, FTIR, SEM and thermal analysis methods. Grinding of colemanite causes the solid-state amorphization of this mineral, as a result of the destruction of its structure along the cleavage plane. The decrease in the particle size of the original material and the increase in its internal structural disorder affect the temperatures and the magnitudes of the thermal effects accompanying the processes of dehydration and dehydroxylation. The diminishing values of the enthalpies of these processes may be a quantitative measure of the degree of amorphization of colemanite.Dedicated to Dr. Robert Mackenzie on the occasion of his 75th birthdayThe author is grateful to Professor L. Stoch for helpful discussions.Support for this work was provided by the Polish Committee for Scientific Research (KBN) — Grant No. 3 P407 034 06. 相似文献
92.
Homopolynuclear complexes of Cu(II) respectively Cr(III) with the glyoxylate dianion, C2H2O4
2-, have been studied in non-isothermal regime in air and nitrogen. The results of the non-isothermal analysis performed for
the synthesised complexes, Cu(C2H2O4)·0.5H2O, respectively [Cr2(OH)2(C2H2O4)2(OH2)4]·2H2O, correlated with the results of the IR and TG analysis of the compounds obtained by thermal treatment from the initial complexes
and the results of the GLC and XR analysis have led to the establishment of the thermal decomposition mechanisms for the two
studied complexes. The decomposition mechanisms confirm the stoichiometric and structural formulae proposed for the two synthesised
homopolynuclear complexes.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
93.
《Discrete Mathematics》2022,345(5):112797
If the line graph of a graph G decomposes into Hamiltonian cycles, what is G? We answer this question for decomposition into two cycles. 相似文献
94.
A Cartesian decomposition of a coherent configuration is defined as a special set of its parabolics that form a Cartesian decomposition of the underlying set. It turns out that every tensor decomposition of comes from a certain Cartesian decomposition. It is proved that if the coherent configuration is thick, then there is a unique maximal Cartesian decomposition of ; i.e., there is exactly one internal tensor decomposition of into indecomposable components. In particular, this implies an analog of the Krull–Schmidt theorem for the thick coherent configurations. A polynomial-time algorithm for finding the maximal Cartesian decomposition of a thick coherent configuration is constructed. 相似文献
95.
作为Hom-Leibniz代数胚的代数类比, 本文引入Hom-Leibniz-Rinehart代数的概念. 证明了分裂的正则Hom-Leibniz-Rinehart代数$L$写成$L=U+\sum_{\gamma}I_\gamma$, 其中$U$为极大交换子代数$H$的子空间和$I_\gamma$为$L$的理想, 若$[\gamma]\neq[d]$, 满足$[I_\gamma, I_d]=0$. 随后分别发展了分裂Hom-Leibniz-Rinehart代数的根和权的连通技术.最后研究了紧致的正则Hom-Leibniz-Rinehart代数的结构. 相似文献
96.
给出 Banach空间列{Xi}i=1∞的 lp乘积B-凸的特征刻划, 证明B-凸空间上的每个黎斯算子可West分解,即分解成一个紧算子和一个拟幂 零算子的和. 相似文献
97.
The Balancing Domain Decomposition algorithm uses in each iteration solution of local problems on the subdomains coupled with a coarse problem that is used to propagate the error globally and to guarantee that the possibly singular local problems are consistent. The abstract theory introduced recently by the first-named author is used to develop condition number bounds for conforming linear elements in two and three dimensions. The bounds are independent of arbitrary coefficient jumps between subdomains and of the number of subdomains, and grow only as the squared logarithm of the mesh size . Computational experiments for two- and three-dimensional problems confirm the theory.
98.
T. Rampke W. -D. Emmerich E. Post L. Giersig 《Journal of Thermal Analysis and Calorimetry》1996,47(2):633-642
The decomposition reactions of polystyrene, phenolic resin and a protective undercoating material for automobiles which contains PVC were tested using a new type of thermal analysis — mass spectrometry coupling system for measurements to 1500C or 2000C, which is based on the principle of a two-step skimmer orifice system. The results will be presented, with particular emphasis on the detection sensitivity of the new system for the products of decomposition.The capability of this coupling system to detect even heavy metals such as lead and silver in the waste gases from decomposition or after evaporation at high temperatures will also be demonstrated. 相似文献
99.
George Adomian 《Foundations of Physics Letters》1993,6(6):603-605
In mathematical approaches to elementary particle theory, the equation [2 -
2/t2]=m2
;+g
3 has been of interest [1,2]; it describes a quartically self-coupled neutral scalar meson field. This paper applies the decomposition method [3-6] to obtain accurate non-perturbative timedevelopment of the field for this equation, or variations involving other nonlinear interactions, without the use of cutoff functions or truncations. 相似文献
100.
The adsorption and photocatalutic decomposition of citric acid on both Pt/TiO2 powder and n-TiO2 single crystal electrode were studied in aqueous solutions of various pH. It was found that citrate ions were chemisorbed on TiO2, which could increase the interfacial capacity and the filling factor of photocurrent-potential curves. The quantity of adsorption, slope of mott-Shottky plot and the rate of photocatalytic decomposition of citric acid were found to depend strongly on pH of solution. The phot ocatalytic decomposition of citric acid was discussed in light of its adsorption on TiO2. 相似文献