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131.
In this paper we rigorously establish the existence of the mobility coefficient for a tagged particle in a simple symmetric exclusion process with adsorption/desorption of particles, in a presence of an external force field interacting with the particle. The proof is obtained using a perturbative argument. In addition, we show that, for a constant external field, the mobility of a particle equals to the self-diffusivity coefficient, the so-called Einstein relation. The method can be applied to any system where the environment has a Markovian evolution with a fast convergence to equilibrium (spectral gap property). In this context we find a necessary relation between forward and backward velocity for the validity of the Einstein relation. This relation is always satisfied by reversible systems. We provide an example of a non-reversible system, where the Einstein relation is valid.This revised version was published online in March 2005 with corrections to the page numbers. 相似文献
132.
We derive tight Bell's inequalities for N>2 observers involving more than two alternative measurement settings. We give a necessary and sufficient condition for a general quantum state to violate the new inequalities. The inequalities are violated by some classes of states, for which all standard Bell's inequalities with two measurement settings per observer are satisfied. 相似文献
133.
134.
Let X be a Polish space and P a Markov operator acting on the space of Borel measures on X. We will prove the existence of an invariant measure with respect to P, provided that P satisfies some condition of a Prokhorov type and that the family of functions is equi-continuous with respect to the Prokhorov distance at some point of the space X. Moreover, we will construct a counterexample which show that the above equi-continuity condition cannot be dropped. 相似文献
135.
Weglarz WP Tanasiewicz M Kupka T Skórka T Sułek Z Jasiński A 《Solid state nuclear magnetic resonance》2004,25(1-3):84-87
A 3D spin-echo (3D SE) pulse sequence was used on a 4.7 T research MRI system to produce images of extracted human first molar tooth placed in CuSO4 water solution. The maximal resolution achieved was 35 x 63 x 300 microm3 in read and two phase directions, respectively. The high-intensity signal from water in solution together with the lack of signal from mineralized tooth tissue produce very good contrast allowing to visualize topography of outer and inner surfaces of the tooth. The 3D MR data were median filtered, binarized and then divided into separate segments corresponding to the inner tooth cavities and the hard tooth tissue. The topography of the root canals was visualized and the canals volume was calculated. The presented technique may be used for quantitative analysis of the root canal cavities shape and volume. The results of such an analysis may be applied for estimation of the quality of the impressional mapping methods in restorative dentistry or as an alternative non-impressional 3D mapping method. 相似文献
136.
137.
The possibility of applying post-column reaction and chemiluminescence to determine organic peroxy compounds by RP-HPLC was investigated. Conditions of qualitative and quantitative analyses have been established. The applicability of the method has been demonstrated for a series of compounds representative of the most important groups of peroxy-type compounds, that is, hydroperoxides, dialkyl peroxides, diacyl peroxides, peroxyesters, and peroxyacids. 相似文献
138.
[reaction: see text]. Mitomycin C is unchanged upon exposure to thiols under physiological conditions. Its more toxic variant, mitomycin A (MA), undergoes elimination of methanol to give a variety of mitosene derivatives, diagnostic of its activation to a reactive electrophile. Evidence is presented for a novel reductive mechanism, characterized by the transient addition of a thiol to the quinone of MA, followed by intramolecular electron transfer, leading to reduced quinone and oxidized thiol. 相似文献
139.
During bicolor optical treatment by two coherent laser beams from 25 ps Erbium-glass laser (λ = 1.54 μm), we have established substantial increase of effective optical second-order susceptibility near the critical temperature points corresponding to the glass structural transformation near 435 °C. The increasing Er3+ content favors substantial increase of the photoinduced optical second harmonic generation (SHG). This temperature dependence of the second-order optical susceptibilities detected by the SHG correlates well with the differential scanning calorimetric (DSC) measurements. At the same time, the effect exists only in a narrow temperature range (up to 12 °C) . There was not temperature hysteresis. Possible physical mechanisms of the phenomenon observed are discussed. 相似文献