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41.
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Morphology of thin anatase coatings prepared from alkoxide solutions containing organic polymer,affecting the photocatalytic decomposition of aqueous acetic acid 总被引:13,自引:0,他引:13
K. Kato A. Tsuzuki Y. Torii H. Taoda T. Kato Y. Butsugan 《Journal of Materials Science》1995,30(3):837-841
Porous anatase coatings were prepared from alkoxide solutions containing organic polymer by a dip-coating technique. The morphology of the coatings, such as pore size, pore distribution and thickness, was controlled. The effects of the morphology of the porous anatase coatings on the photocatalytic activity for the photocatalytic decomposition of aqueous acetic acid were examined. 相似文献
43.
INTRODUCTION AND DEVELOPMENT: Multiple sclerosis (ME) is an inflammatory disease of the myelin of the central nervous system, the origin of which is still unknown. Genetic, infectious, immunological and environmental factors have all been blamed, but none of these factors on their own can explain the whole spectrum of this disease. Of the environmental factors, fat in the diet has given rise to most discussion. At the present time, it is known that polyunsaturated essential fatty acids form a part of biological membranes. A relationship has been found between the dietary fat consumed and the plasma levels and cell membrane content. CONCLUSIONS: The possible immuno-modulation function of these fatty acids justify rigorous evaluation of this hypothesis. 相似文献
44.
José Martínez-Aroza Ramón Román-Roldán 《Multidimensional Systems and Signal Processing》1995,6(1):7-35
A multiresolution analysis of digital gray-level images is presented. A gray-level multi-scale framework is determined from two main assumptions: the gray scale is binary at the finest spatial resolution, and the gray levels of composed regions are obtained additively. In order to interrelate the gray-level histograms of the same image at different resolutions, probabilistic linear models are developed, which are then applied for estimation. Linear-optimization theory is used as a way of constructing such models. A general procedure for image processing is sketched, based on gray-level estimation. A versatile algorithm for nonlinear filtering is derived. Some examples of prospective applications are given.This work was partially supported by grant TIC91-646 from the DGYCIT of the Spanish Government. 相似文献
45.
C André 《Canadian Metallurgical Quarterly》1994,52(3):339-342
PURPOSE: Evaluate current practice in a university hospital on management of high blood-pressure in patients in the acute phase of brain infarction (BI). METHODS: A case report of a lucid patient admitted 8 hours after onset of a BI with normal CT and high blood pressure (BP = 186/110 mmHg) was presented to staff members and resident physicians (departments of neurology and neurosurgery excluded). Responders were asked to decide as to the best therapeutic option: no treatment/reduction/elevation of BP. RESULTS: 27 of 44 responders (61%) considered BP reduction as the best treatment option. The same trend was observed among residents (16/27: 60%) and staff members (11/17: 65%); among surgeons (6/12: 50%) and clinicians (20/30: 67%). CONCLUSIONS: BP reduction in the hyperacute phase of BI may be harmful. This basic concept of BI management has not been adequately assimilated by physicians of our university hospital, including those recently graduated. The results of this study signal to the urgent need of a wide diffusion of current concepts on pathophysiology and treatment of BI. Organization of stroke units may contribute to better patient management, medical education and research. 相似文献
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The first stages of nickel electrodeposition on amorphous carbon and polycrystalline silver substrates have been studied under galvanostatic conditions. An island growth mode is observed on the two types of substrate. For equivalent conditions the cluster density is higher on silver substrates than on carbon substrates. Dissolution of some nickel clusters is observed a short time after the onset of electrolysis on carbon substrates. This is confirmed by the evolution of the current efficiency and the evolution of the metal surface cluster density as a function of the quantity of electricity. 相似文献
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The Bi2O31bM2O5 films (M=V, Nb and Ta) were prepared by a rapid quenching technique using a twin-roller type equipment. Quenched film of pure Bi2O3 partially precipitated a tetragonal phase which differs from well-known β-Bi2O3 in structure. In every (Bi2O3)0.975 (M2O5)0.025 composition (2.5% M2O5), the tetragonal phase was obtained as single phase, and the tetragonality became greater than that of the pure Bi2O3. Beyond this composition, the tetragonality decreased to form δ-phase with a fcc structure with increasing the M2O5 content. The lowest V2O5 content forming a δ-phase was 5%, while a slight tetragonality still remained in the samples containing 10% Nb2O5 and 10% Ta2O5, respectively. From the measurement of the photoconductivities of the quenched films, it was proved that a photoconduction appeared in the tetragonal phase while no photoconductivity was observed in the cubic phase. The characteristic of the photoconduction was that a remarkable decrease in the resistivity was observed when a light of ca. 500 nm in wave length was irradiated on the films. 相似文献