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141.
Martin Macháček 《Journal of statistical physics》1987,47(5-6):949-952
We define mathematically a class of dynamical systems that exhibit relaxation corresponding to that observed in physical systems, and then show that this class is identical with the class ofK-mixing dynamical systems. 相似文献
142.
The stochastic theory of the crystal growth is compared with the solution of the Stefan problem in the case of Sn solidification. It is shown that the stochastic theory gives the same results as the solution of the Stefan problem if kinetic processes at the solidification front are very rapid. 相似文献
143.
144.
145.
146.
G. P. Kamuntavičius 《Few-Body Systems》1986,1(2):91-109
We present a new method of a direct derivation of differential equations for the wave-function components of identical-pariticles systems. The method generates in a simple manner all the possible variants of these equations. In some cases they are the differential equations of Faddeev of Yakubovskii. It is shown that the case of the bound states allows to formulate very simple equations for the components which are equivalent to the Schrödinger equation for the complete wave function. The components with a minimal antisymmetry are defined and the corresponding equations are derived. 相似文献
147.
Elías Molins Amílcar Labarta Javier Tejada Amparo Caubet Santiago Alvarez 《Transition Metal Chemistry》1983,8(6):377-380
Summary Magnetic moments and57Fe Mössbauer spectra at room temperature and at liquid nitrogen temperature of polynuclear ligand-bridged iron phthalocyanines, FePcL (L = pyrazine and 4,4-bipyridyl), are reported. The experimental data are in agreement with a pseudo-octahedral environment around the iron(II) cation. Partially oxidized derivatives, FePc(pz)I0.26 and FePc(bipy)I1.06 have been synthesized and their57Fe Mössbauer spectra and magnetic moments within the same temperature range obtained. Oxidation is shown to be metal centred and the iodine is found to be in I– form for FePc(pz)0.26 and as both I– and I
3
–
species for FePc(bipy)I1.06. While the magnetic moment of FePc(pz) increases upon oxidation, the opposite occurs for FePc(bipy). 相似文献
148.
The diamagnetic square planar d(8) complexes [meso-arylcorrolato]copper(III) become paramagnetic upon warming, indicative of the equilibrium between the [corrolato]copper(III) and the [corrolato](+)* copper(II) forms of the complex. [meso-Triphenylcorrolato]copper(III) was structurally characterized and found to be saddled. 相似文献
149.
The raw material used in the production of fetilizers is phosphate ore containing various amounts of naturally radioactive elements. During phosphate ore processing, owing to chemical properties of radium, practically all226Ra gets incorporated into phosphogypsum and becomes the main source of radioactivity. This study was carried out in a fertilizer factory in central Croatia, which may represent a site of significant environmental contamination due to fertilizer production and phosphogypsum deposition in the area. The purpose of this paper was to determine whether ingestion of drinking water in this area poses a health risk for the inhabitants. The results of our study confirmed the occurrence of226Ra in elevated concentrations in the samples of trickling waters. However, concurrent analyses of drinking water indicated that the risk of adverse health effects for the population living in the vicinity of a phosphate fertilizer plant is negligible. 相似文献
150.
Josef Janča 《Mikrochimica acta》1994,112(5-6):197-215
The primary field forces can generate spatially oriented gradient of the effective property of a continuum or pseudo-continuum fluid (carrier liquid). When this gradient is coupled with the action of a secondary field of identical or different nature the isoperichoric focused zones of the dispersed species can appear. Consequently, they can be separated according to differences responding to the property gradient of the carrier liquid. This concept can be applied under static (non-flow) conditions in thin layer focusing as well as under dynamic conditions with the elution due to the carrier liquid flow in focusing field-flow fractionation. The gradient established by the action of the primary field and the concentration distribution of the isoperichoric focused zone formed by the coupled effect of the gradient and of the primary or secondary field are described theoretically. The rigorous relationship describing the shape of the focused zone is compared with the approximate solutions. The performances of the proposed principle were evaluated by model calculations. Potential experimental configurations considering the implementation of the static and dynamic conditions are discussed. The generalized isoperichoric focusing theory can be applied to describe the particular processes operating in analytical and preparative focusing separations of the particles of various, but especially of biological origin. 相似文献