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排序方式: 共有598条查询结果,搜索用时 15 毫秒
1.
D. Vignolles D. Smirnov G. Rikken B. Raquet H. Rakoto C. Proust M. Nardone J. Léotin F. Lecouturier M. Goiran O. Drachenko J. M. Broto L. Brossard A. Audouard 《Journal of Low Temperature Physics》2003,133(1-2):97-120
An overview over past and present activities and future developments at the Toulouse pulsed magnetic field facility is given, both as far as technical developments of the infrastructure, as well as low temperature physics performed at the LNCMP are concerned. 相似文献
2.
Jean-Michel L. Bernard 《电信纪事》1994,49(11-12):673-683
The time-scattering of an electromagnetic wave by a wedge-shaped region in a lossy medium, both with frequency dependent electric characteristics, is analyzed for plane wave and line source illuminations. New exact analytical expressions, satisfying explicitely the causality and allowing useful physical decompositions of the field, are obtained in these cases, using the particularities of the harmonic response in Sommerfeld-Maliuzhinets integral, especially original properties of the spectral function attached to it. 相似文献
3.
A space reactor power system (SRPS) has been developed for avoidance of single point failures in reactor cooling and energy conversion. The sectored compact reactor (SCoRe) in this system is lithium-cooled and the reactor core is divided into six equal sectors with liquid metal heat pipes dividers. These reactor sectors are neutronically, but not thermal-hydraulically, coupled. Each sector has its own primary and secondary circulating lithium loops, which are thermally coupled both in a SiGe thermoelectric (TE) power conversion assembly (PCA) and a thermoelectric conversion assembly (TAC) that powers the electromagnetic pumps in the primary and secondary loops. Each secondary loop also has a separate, segmented radiator panel that is optimized for low specific mass and low liquid lithium inventory. The primary loops transport the thermal power generated in the reactor to six PCAs that nominally supply a total of 111.5 kWe to the load at 450 V DC. Each of the 12 primary and secondary loops has its own bellows-type accumulator that is designed to regulate the lithium pressures in the loops. A dynamic simulation model of this thermoelectric SRPS (DynMo-TE) has been developed and used to investigate the transient operation of the system during a startup from a fully-thawed condition at 600 K, to nominal steady-state operation at which the lithium coolant exits the reactor at only 1179 K. Also investigated is the load-following characteristic of the SCoRe-TE SRPS, following a change in the electrical load demand. 相似文献
4.
Pierre Darcy Patrick Da Costa Henry Mellotte Jean-Michel Trichard Grald Djga-Mariadassou 《Catalysis Today》2007,119(1-4):252-256
To comply with the new regulations on particulate matter, car manufacturers more and more commonly use diesel particulate filters (DPF). The working of these systems needs to periodically burn soot that has been accumulated during the loading of the DPF. This paper describes the kinetics of the non-catalytic and catalytic oxidation of real diesel soot with oxygen. From these experiments, mechanisms for catalyzed and non-catalyzed soot oxidation have been proposed. 相似文献
5.
B Godeau E Oksenhendler Y Brossard J Bartholeyns JB Leaute N Duedari A Schaeffer P Bierling 《Canadian Metallurgical Quarterly》1996,36(4):328-330
BACKGROUND: The platelet count increases transiently after treatment with polyclonal anti-D in about 50 percent of D+ patients with autoimmune thrombocytopenic purpura (AITP). The effect is usually attributed to macrophage Fc-receptor blockade by antibody-coated red cells. As polyclonal anti-D is in limited supply, prospective testing was performed on a monoclonal anti-D (MoAb D) in such patients. STUDY DESIGN AND METHODS: Seven D+ patients with chronic AITP received MoAb D intravenously at doses of 47 to 95 microg per kg of body weight. Response was assessed by studying platelet count increment. Hemolysis and red cell-bound MoAb D were measured before and after MoAb D administration. RESULTS: MoAb D red cell binding was demonstrated in all patients at a ratio higher than that observed in AITP patients successfully treated with polyclonal anti-D. However, little or no platelet count increment was observed in six patients, while a transient response was observed in only one (platelet count 97 x 10(9)/L before MoAb D infusion and 163 x 10(9)/L 4 days later). Furthermore, because five patients showed signs of hemolysis and two became anemic, higher doses of MoAb D should be used only with caution in patients with AITP. CONCLUSION: The MoAb D used in this study cannot be proposed as an alternative treatment for patients with AITP. 相似文献
6.
Cagnon Christine; Valverde Viviane; Masson Jean-Michel 《Protein engineering, design & selection : PEDS》1991,4(7):843-847
A set of 11 expression vectors was constructed, each of themharbouring a cloning cassette under the control of the promoter.Some of these vectors enable expression of foreign proteinsin the cytoplasm, while others include a synthetic sequencecoding for a very efficient secretion signal sequence. Otherfeatures are an fl origin of replication (in plus or minus orientation)and a promoterup mutation that enhances the already very highlevel of expression from these vectors. With such a versatilevector family, cloning, sequencing and sitedirected mutagenesiscan be performed on the same vector, and the level of expressioncan be defined according to the specific constraints of a givenprotein. 相似文献
7.
François Treussart Nicolas Dubreuil Jongthan Cave Knight Vahid Sandoghdar Jean Hare Valçrie Lefçvre-Seguin Jean-Michel Raimond Serge Haroche 《电信纪事》1997,52(11-12):557-568
Light can be confined efficiently in the high-Q, small-volume whispering-gallery-modes observed in silica microspheres. By coupling these microspheres to eroded optical fibers and fiber tips, direct mapping of the whispering-gallery modes has been achieved and the mode numbers have been assessed. The properties of these modes have allowed us to obtain laser action with very low thresholds in Nd-doped silica microspheres. Further projects in the field of non-linear optics and cavity quantum electrodynamics are described. 相似文献
8.
P. Dubé F. Kerdouss F. Laplante P. Proulx L. Brossard H. Ménard 《Journal of Applied Electrochemistry》2003,33(6):541-547
The electrocatalytic hydrogenation of cyclohexanone has been investigated with catalytic powder particles made of metal nanoaggregates deposited on a nonconductive material such as activated carbon and alumina. The catalytic powder particles were suspended in the solution under vigorous stirring conditions. The brief contact of the powder particles with a porous carbon cathode was sufficient to form adsorbed hydrogen on the metallic nanoaggregates through water electrolysis and initiate the electrohydrogenation process. It is demonstrated that the key parameters of the electrohydrogenation process are both the nature of the metallic nanoaggregates and the nature of the non-conductive material. The hydrodynamics of the solution under vigorous stirring conditions have also been studied for the particular cell used in the present study. 相似文献
9.
Grant McClelland Georges Zwingelstein C. Richard Taylor Jean-Michel Weber 《Lipids》1995,30(2):147-153
The goals of this study were to determine: (i) whether mammals mobilize particular nonesterified fatty acids (NEFA) preferentially
during locomotion, (ii) if differences in aerobic capacity or diet can affect the pattern of NEFA mobilization and (iii) which
individual NEFA are most representative of total NEFA concentration changes, to use them as tracers for turnover studies.
Individual NEFA were measured in trained dogs and goats (VO2max dog/VO2max goat=2.2; where VO2max=max-imal oxygen consumption) during treadmill exercise at 40 and 60% VO2max. Important interspecies differences in individual NEFA concentrations could be attributed to differences in aerobic capacity.
The more aerobic species (dog) had much higher plasma NEFA concentrations for all but one NEFA (18∶0), when compared with
the low-aerobic species (goat). In addition, exercise caused a large increase in concentration of individual NEFA in the dogs,
with the largest increases seen in 18∶1 (150% above resting values) and 16∶0 (60% increase), but it had no effect in goats.
Therefore, the aerobic species has a much higher ability for mobilizing and transporting NEFA in plasma than its low-aerobic
counterpart. Two NEFA accounted for more than half total plasma NEFA in both species, 18∶1 (about 35% total NEFA) and 16∶0
(20%). Calculation of variability in percent composition reveals that oleate and palmitate also closely reflect changes in
total NEFA and are therefore the most appropriate tracers forin vivo kinetic studies in exercising mammals. Differences in diet and digestion physiology explained some differences in the plasma
NEFA composition of the two species; this was reflected in the percent contributions of individual fatty acids to total NEFA:
in dogs 18∶1>16∶0>18∶2>18∶0, while in goats 18∶1>16∶0>18∶0>18∶2. Also, only goats had 18∶3 (6% total NEFA), a fatty acid of
plant origin, while only dogs had 16∶1 (7% total NEFA). Overall, however, the plasma NEFA composition of goats did not exactly
reflect that of their diet due to preabsorptive modification of unsaturated fatty acids, while in dogs there was a good correlation
between dietary and plasma NEFA. 相似文献
10.
Edwin Ramaroson Gilbert Blanchard Michel Che Jean-Michel Tatibouët 《Catalysis Letters》1992,15(4):393-400
The oxidative dimerisation of propene to 1,5-hexadiene has been investigated on Bi-Zn-O catalysts. The Bi48ZnO73 phase, observed in the catalysts calcined at 700 ° C is an active and selective catalyst for the formation of 1,5-hexadiene. The best catalytic performance (1,5-hexadiene selectivity 64%) has been obtained at 525 ° C, with a propene to oxygen ratio of 26, on a catalyst formed by Bi48ZnO73 with a small excess of ZnO. 相似文献