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111.
The equilibrium and transport properties of interacting ad-particles on bivariate heterogeneous chains are studied by combining analytical and simulation approaches. Heterogeneity is introduced in the way of patches of shallow and deep adsorbing sites distributed in a deterministic alternating way. Adsorption isotherms and mean-square fluctuations of the surface coverage, as well as the jump and collective diffusion coefficients, are calculated for different values of lateral interactions between ad-particles and substrate heterogeneity. In addition, different elementary jump mechanisms are introduced and their influence in the coverage dependence of the collective diffusion coefficient is investigated. 相似文献
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In this paper we are concerned with the adhesion of lipid tubules to a plane wall: we treat both the statics and the dynamics
of this phenomenon. Though we provide an exact solution to the equilibrium problem, our treatment of the dynamical problem
is approximate, as it is based on a simplified model, which, nevertheless allows us to obtain quantitative information about
the detachment dynamics of tubules.
Received September 1, 1997 相似文献
116.
The behavior of a cw dye laser under variation of the output coupling has been investigated. By studying the dependence of
laser threshold, output power and slope efficiency on the degree of outcoupling, numerical values for macroscopic and microscopic
laser parameters have been obtained. The macroscopic data comprise values for internal cavity losses and mode matching conditions,
the microscopic data refer to molecular parameters of the dye used, such as cross-sections for stimulated emission and triplet-triplet
absorption. 相似文献
117.
Riccardo Goldoni 《General Relativity and Gravitation》1983,15(7):691-699
We propose a bimetric machian approach to gravitation with a mathematical structure much simpler than the one of Rosen's bimetric theories. We obtain two cosmological models based on the simplest assumption that the Universe be filled of pure dust matter. One of the two cosmological models is compatible with the currently observed value of the density of dust matter, and provides an age of the Universe which is of the order of the inverse of the present Hubble parameter. One also obtains the Schwarzschild-like solution and its Newtonian limit together with the modified three Kepler laws which allow us to find that presently 0.5×10?10 (yr)?1 δ(A/A)δ 0.625×10?10 (yr)?1, a denoting the semimajor axis of the orbit of the test particle. Lastly we obtain the Newtonian limit of the theory. 相似文献
118.
Donati A Pulselli FM Riccobono F Dallai L Francovich R Tiezzi E 《Annali di chimica》2005,95(3-4):161-166
The Colline Metallifere in SW Tuscany are characterized by strong anomalies in arsenic concentrations and distribution. The area is sparsely populated and largely wild, though it has been subject to human impact due to mining and metal processing since Etruscan and Roman times. In the Middle Ages it was exploited intensively for silver and copper. Until 1995, pyrite (FeS2) was mined and roasted to produce sulphuric acid and iron. Hypotheses based on geological and mineralogical factors formulated in the last 20 years have failed to explain the peculiar distribution of arsenic in the Colline Metallifere. Here we report preliminary results of widespread sampling and analysis of the fluvial sediments of rivers originating in this mining area. The data was analysed in relation to the archaeological features of the area, since the presence of ancient mining and ore processing sites can shed light on the peculiar distribution of arsenic. Comparison of data from two rivers and their respective contaminated and uncontaminated coastal lagoons also clarified the general mechanisms of arsenic mobility, pinpointing the source of arsenic contamination. The study methods also promise to be useful for discovering unknown archaeological sites. 相似文献
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