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161.
Translated from:Problemy Ustoichivosti Stokhasticheskikh Modelei, Trudy Seminara, 1989, pp. 20–26.  相似文献   
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The uptake of137Cs and90Sr/90Y onto Syrian bentonite has been studed, using batch and column tracer techniques in order to investigate its utilization for aqueous radioactive effluent treatment. Parameters influencing the percent uptake considered and studied in this work are: nuclide concentration, pH of the aqueous phase, heat treatment and particle size. Leaching experiments using natural sea and ground waters were carried out on bentonite/cement composites. They demonstrated the effectiveness of calcination and cement containment.  相似文献   
164.
Sampling, homogenisation and sample preparation prior to chromatographic injection of food analytes are designed to enhance accuracy and precision. The reduction of inherent errors introduced by these steps requires the analyst's attention as a matter of course. Methods and examples of minimising errors in each step are reviewed.  相似文献   
165.
The aim of this article is to define a model that describes the evolution of the yield surface during plasticity. We propose a modelisation that is completely different from the classical approach as far as conception is concerned. It consists of describing the yield surface evolution with the help of velocity. The yield function is not directly known but is obtained by integrating a differential law starting from an initial surface. A very simple evolution law is used; the complexity of the induced anisotropy is obtained by incremental accumulation.  相似文献   
166.
Summary We report on novel optical techniques, based on evanescent waves, for the characterization of polymer surfaces and thin films. We first describe photo-ablation studies with polysilane films investigated by surface plasmon microscopy, a technique which is particularly well-suited for ultrathin samples. Thicker films that are homogeneous enough to carry optical waveguide modes can be characterized with high lateral resolution by the recently developed waveguide microscopy. We demonstrate this for a thin film of a solid polyelectrolyte. Finally, we report on surface plasmon field-enhanced Raman-spectroscopic and -imaging investigations of ultrathin Langmuir-Blodgett-Kuhn-layers of cadmium arachidate.W. Hickel is now with HOECHST AG, Angewandte Physik, W-6230 Frankfurt 80  相似文献   
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Measurements of the anomalous magnetic moment of the muon are reviewed. The emphasis is put on the first one of a series of three CERN experiments which led to an experimental value ofa=1165922.9 (8.5)·10−9 (±7.2ppm), and which compares well with the present theoretical resulta=1165919.2 (1.8)·10−9 (±1.5ppm).  相似文献   
170.
The existence of bound states and resonances of the Hamiltonian of a system ofN different quantum lattice particles with nonvanishingN-particle short-range interaction is proved. The dependence of the bound states and the resonances on the coupling constant and the quasimomentum is studied.Samarkand State University. Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 91, No. 1, pp. 51–65, April, 1992.  相似文献   
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