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341.
The adsorption of nonionic surfactant Triton X-100 on quartz sand and methylated quartz sand from water and toluene was investigated by means of spectrophotometry, the radiotracer technique, and wetting angle measurements. 相似文献
342.
Choyal Y. Minami K. Granatstein V.L. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》2004,32(6):2157-2168
The linear dispersion relation of a backward-wave oscillator (BWO), derived earlier by the authors, is modified to include effects of RF surface current at the beam-vacuum interface. This modified dispersion relation results in an unstable interaction between the slow cyclotron mode (SCM) and the structure mode in addition to the conventional Cherenkov instability caused by the slow space charge mode. Numerical analysis is then carried out using parameters of a BWO experiment at University of Maryland. Fine structure of the SCM instability is elucidated. The analysis indicates that BWO radiation would not be suppressed near cyclotron absorption in an infinitely long system. 相似文献
343.
344.
Audrey A S G Lonni Ieda S Scarminio Lucas M C Silva Dalva T Ferreira 《Analytical sciences》2003,19(7):1013-1017
Phytochemical investigation of the aerial parts of three Baccharis species (Asteraceae family) was performed using HPLC and chemometric methods, with the objective of distinguishing between three morphologically very similar species: Baccharis genistelloides Persoon var. trimera (Less.) DC, B. milleflora (Less.) DC and B. articulata (Lam.) Persoon. With the help of Principal Component Analysis (PCA) and variance weights, it was possible to characterize the chromatographic profiles of the alcoholic extracts of the three species. Application of Soft Independent Modeling of Class Analogy (SIMCA) and K-Nearest Neighbor (KNN) methods on a training set of 74 extracts resulted in models that correctly classified all eight samples in an independent test set. 相似文献
345.
V. T. Bublik S. Yu. Matsnev K. D. Shcherbachev M. V. Mezhennyi M. G. Mil’vidskii V. Ya. Reznik 《Physics of the Solid State》2003,45(10):1918-1925
Diffuse x-ray scattering (DXS) is used to study the formation of microdefects (MDs) in heat-treated dislocation-free large-diameter silicon wafers with vacancies. The DXS method is shown to be efficient for investigating MDs in silicon single crystals. Specific defects, such as impurity clouds, are found to form in the silicon wafers during low-temperature annealing at 450°C. These defects are oxygen-rich regions in the solid solution with diffuse coherent interfaces. In the following stages of decomposition of the supersaturated solid solution, oxide precipitates form inside these regions and the impurity clouds disappear. As a result of the decomposition of the supersaturated solid solution of oxygen, interstitial MDs form in the silicon wafers during multistep heat treatment. These MDs lie in the {110} planes and have nonspherical displacement fields. The volume density and size of MDs forming in the silicon wafers at various stages of the decomposition are determined. 相似文献
346.
A. Touraille 《Algebra Universalis》1995,33(2):196-206
Presented by S. Burris. 相似文献
347.
We give sufficient conditions for a finite permutation groupto contain a fixed-point-free permutation of p-power order fora given prime p. 相似文献
348.
A. M. Gurin 《Journal of Mathematical Sciences》2007,146(1):5505-5508
The number of combinatorially nonequivalent Dirichlet-Voronoi diagrams constructed for the centers of balls in the packing
obtained from the densest lattice packing of equal spheres by a small displacement of the spheres is estimated.
__________
Translated from Fundamentalnaya i Prikladnaya Matematika, Vol. 11, No. 5, pp. 79–84, 2005. 相似文献
349.
A. G. Chentsov 《Russian Mathematics (Iz VUZ)》2007,51(11):55-68
We consider a problem which implies the choice of a solution subject to asymptotic constraints. We represent the results as ultrafilters of the space of ordinary estimates (the space is not necessarily endowed with a topology). This representation corresponds to an abstract attainability problem in its nonsequential asymptotic version. 相似文献
350.
A. M. Raigorodskii 《Journal of Mathematical Sciences》2007,146(2):5723-5730
This work deals with some problems on the embeddings of finite geometric graphs into the random ones. In particular, we study here applications of the random graph theory to the Nelson-Erdös-Hadwiger problem on coloring spaces. 相似文献