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排序方式: 共有1014条查询结果,搜索用时 15 毫秒
71.
72.
Size effects on the DC characteristics and low frequency noise of double polysilicon NPN bipolar transistors 总被引:1,自引:0,他引:1
Nicolas Valdaperez Jean-Marc Routoure Daniel Bloyet Rgis Carin Serge Bardy 《Microelectronics Reliability》2005,45(7-8):1167-1173
DC and low frequency noise measurements have been carried out for double polysilicon NPN bipolar transistors. Our experiments have highlighted unexpected geometrical dependencies for the base saturation current density and low frequency noise. A model, taking into account a variation of the interfacial oxide thickness at the periphery of the emitter has been proposed and it has been successfully applied to the experimental results. 相似文献
73.
Gwenael Jouet Eric W.H. Hutton James P.M. Syvitski Serge Berné 《Computers & Geosciences》2008,34(10):1338-1357
Passive continental margin subsidence is initiated by the synrift mechanical stretching of the lithospheric upper brittle layer and continues during the postrift phase; the thermal cooling and contraction of the upwelled asthenosphere forces the margin to subside in addition to the overloads from sea water and sediments. Therefore, the total subsidence in stretched basins includes fault-controlled initial sinking, thermal subsidence and flexural isostatic compensations. Decoupling and estimating the different components of this subsidence from stratigraphic analysis and restricted geophysical and sedimentological databases remains problematic. In particular, backstripping the sediment layers requires a well-constrained geological framework. A method is proposed here to investigate the subsidence history of a margin based on forward stratigraphic modelling. Using the Sedflux model, several experiments are done using generally agreed upon assumptions on the parameters describing lithospheric rheology and isostatic behaviour of a margin. The stratigraphic modelling of the Rhône deltaic margin during the last climatic cycle (125 kyr) provides an assessment of these parameter estimates and their influence on geohistory (tectonic/thermal subsidence and sediment loading). The model results confirm the important impact of water loading on vertical deflection along the platform between glacial low sea-level and interglacial high sea-level. Based on Gulf of Lions (NW Mediterranean) observations, a conceptual method that uses the stratigraphic simulations is produced in order to evaluate the different components of the total subsidence of a margin, and, in particular, the relative impact of tectonic subsidence and sediment load. 相似文献
74.
75.
Larivée Serge; Tremblay Richard E.; Charlebois Pierre; Gagnon Claude 《Canadian Metallurgical Quarterly》1989,21(1):16
Studied the association among paternal dogmatism, socioeconomic status (SES), and cognitive development using Piagetian tasks. Human subjects: 98 male and female French-Canadian schoolage children and adolescents (aged 144–171 mo) (1st class of students in the secondary school). 98 male French-Canadian adults (aged 32–62 yrs). All Ss were from 2-parent families and consisted of 50 father–daughter and 48 father–son dyads. Paternal dogmatism was measured using the French-Canadian version of the Rokeach Scale by M. Rokeach (1960). Cognitive levels were evaluated using Piaget and Inhelder"s Permutations Test (1951). Ss" SES was measured using B. R. Blishen and H. A. McRobert"s Socioeconomic Index (1976). The results of the cognitive performance tests were analyzed statistically according to age, sex, dogmatism, and SES, using an analysis of variance (ANOVA). (English abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
76.
77.
In this note, we prove that the complexity of scattering in an oriented ring of p processors is (p - 1) (β + Lτ) where L is the length of the messages, β the communication startup, and τ the elemental propagation time. 相似文献
78.
Marie‐Lonie Delcourt Serge Turcaud Erica Benedetti Laurent Micouin 《Advanced Synthesis \u0026amp; Catalysis》2016,358(8):1213-1218
Herein we wish to report a new non‐enzymatic kinetic resolution of racemic 4‐formyl[2.2]paracyclophane based on Noyori asymmetric transfer hydrogenations (KR‐ATH). Our approach, which provides an efficient access to enantiopure (Rp)‐ and (Sp)‐4‐formyl[2.2]paracyclophane (>99% ee, 39% and 41% isolated yields, respectively), is operationally simple and can be run on the gram‐scale thus confirming the practical applicability of this method.
79.
Sylvie Valin Serge Ravel Jacques Guillaudeau Sébastien Thiery 《Fuel Processing Technology》2010,91(10):1222-1253
Wood sawdust gasification experiments were performed in a steam fluidized bed at 800 °C between 2 and 10 bar. An evolution of gas yields with time was measured during the tests, and especially an increase of hydrogen and carbon dioxide yields. This test duration effect was ascribed to char build-up in the bed. As tests proceed, the contribution of char steam gasification to gas yield increases, and the catalytic effect of char on hydrocarbons and tar conversion and on water-gas shift reaction is enhanced.As total pressure increases from 2 to 10 bar, hydrogen, carbon dioxide and methane yields increase by 16%, 53% and 38% respectively, whereas carbon monoxide yield decreases by 33%. The changes in gaseous yields with pressure can be partly explained by the influence of pressure on gas phase reactions (acceleration of water-gas shift kinetics and change in hydrocarbon reactions). The increase of methane yield with pressure is rather suggested to be linked to a change in secondary pyrolysis reactions scheme under high pressure. 相似文献
80.
Frédéric Pons Mohammed Cherkaoui Idriss Ilali Serge Dominiak 《Journal of Electronic Materials》2010,39(4):456-463
This paper describes a study of the evolution of the AgCdO contact material surface microstructure as a function of the number
of electrical arcs imposed on the switching surface. Five power switching devices were tested under different conditions.
They were subjected to, respectively, 1, 2, 3, 10, and 100 electrical arcs under the same operating conditions: supply current
of 400 A, circuit voltage of 28 V direct current (DC), and resistive load. For the analysis, a binocular microscope and a
scanning electron microscope with an energy-dispersive x-ray spectrometer were used. 相似文献