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排序方式: 共有351条查询结果,搜索用时 265 毫秒
271.
A. Bauchet I. Deloncle M.-G. Porquet A. Astier N. Buforn M. Meyer S. Perriès N. Redon B.J.P. Gall F. Hoellinger N. Schulz G. Duchêne S. Courtin Ts. Venkova P.A. Butler N. Amzal R.D. Herzberg A. Chewter R. Cunningham M. Houry R. Lucas W. Urban A. Nowak E. Piasecki J. Duprat C. Petrache T. Kröll 《The European Physical Journal A - Hadrons and Nuclei》2001,10(2):145-150
High-spin states of 103
43Tc have been identified for the first time, this nucleus being produced as fission fragment following the fusion reaction
37Cl + 176Yb at 170 MeV bombarding energy. The high-spin level scheme has been built from the prompt gamma rays detected using the Euroball
III array. It exhibits similarities with those of the neighbouring isotopes and isotones. All the band head configurations
observed in the 97-105Tc isotopes are identified from the behaviour of the rotational bands built on them. The single-proton states located around
the Fermi level are discussed as a function of deformation of these nuclei.
Received: 19 January 2001 / Accepted: 23 February 2001 相似文献
272.
Jiandong Zhang Yanyan Zhang Marie Collin Stephane Gin James J. Neeway Tieshan Wang Zihua Zhu 《Surface and interface analysis : SIA》2019,51(2):219-225
The hydrogen (H)/sodium (Na) interface is of great interest in glass corrosion research. Time-of-flight secondary ion mass spectrometry (ToF-SIMS) is one of the few techniques that can provide nanoscale H and Na imaging simultaneously. However, the optimized condition for ToF-SIMS imaging of H in glass is still unclear. In H depth profiling using ToF-SIMS, H background control is a key, in which an analysis ion beam and a sputtering ion beam work together in an interlaced mode to minimize it. Therefore, it is of great interest to determine if an auxiliary sputtering ion beam is also necessary to control H background in ToF-SIMS imaging of H. In this study, H imaging with and without auxiliary sputtering beams (Cs+, O2+, and Arn+) was compared on a corroded international simple glass (ISG). It was surprising that the H/Na interface could be directly imaged using positive ion imaging without any auxiliary sputtering ion beam under a vacuum of 2 to 3 × 10−8 mbar. The H+ background was about 5% atomic percent on the pristine ISG glass, which was significantly lower than the H concentration in the alteration layer (~15%). Moreover, positive ion imaging could show distributions of other interesting species simultaneously, providing more comprehensive information of the glass corrosion. If an auxiliary O2+ sputtering ion beam was used, the H+ background could be reduced but still higher than that in the depth profiling. Besides, this condition could cause significant loss of signal intensities due to strong surface charging. 相似文献
273.
R. Razafindrabe Christian Aubry Sylvain Bourdon Benjamin Andriantsiferana Marta Pellet-Rostaing Stephane Lemaire Marc 《中国科学:化学(英文版)》2010,53(9):1888-1898
A synthesis of functionalized phenolic α-amino-alcohols (±)-8 and (±)-16 as synthetic precursors of the catechol tetrahydroisoquinoline structure of phthalascidin 650 was disclosed. (±)-8 was prepared in 5 steps from the commercially available sesamol. Starting from 3-methyl catechol 5, 8 steps gave rise to the synthesis of phenolic α-amino-alcohol (±)-16 in 27% overall yield. This synthetic strategy involved the elaboration of fully functionalized aromatic aldehyde 13 and its transformation into a phenolic α-amino-alcohol (±)-16, through a Knoevenagel condensation, simultaneous reduction of nitroketene and ester functions, and hydrogenolysis of the benzyl protecting group. The pentacycle (±)-4 was obtained after 4 additional steps. The Pictet-Spengler cyclisation between the phenolic α-amino-alcohol (±)-16 and the N-protected α-amino-aldehyde 4 allowed to obtain (1,3′)-bis-tetrahydroisoquinoline 17 with N-methylated and N-Fmoc removed. The last step was a Swern oxidation allowing the expected intramolecular condensation. 相似文献
274.
Rekia Meriem Ahmed Bacha Abdellatif El Badia Ahmad El Hajj Stephane Mottelet 《Mathematical Methods in the Applied Sciences》2020,43(15):8379-8405
In this paper, we are interested in the study of an inverse problem that occurs during the pressing of rapeseeds, where some physical parameters influence on rapeseed oil extraction yield. Our objective is to identify the consolidation coefficient of the press cake, the inverse characteristic time of consolidation in press cake, and inside the rapeseed in order to increase the rapeseed oil extraction yield. Three questions will be addressed: the identifiability, the identification, and the stability of the inverse problem. Finally, we provide numerical results to confirm the theoretical results. 相似文献
275.
276.
Henry RG Lauritsen T Khoo TL Ahmad I Carpenter MP Crowell B Dossing T Janssens RV Hannachi F Korichi A Schuck C Azaiez F Beausang CW Beraud R Bourgeois C Clark RM Deloncle I Duprat J Gall B Hubel H Joyce MJ Kaci M Lecoz Y Meyer M Paul ES Perrin N Poffe N Porquet MG Redon N Sergolle H Sharpey-Schafer JF Simpson J Smith AG Wadsworth R Willsau P 《Physical review letters》1994,73(6):777-781
277.
B. J. P. Gall M. G. Porquet F. Hannachi A. Korichi I. Ahmad M. Aiche F. Azaiez G. Bastin C. W. Beausang R. Béraud C. Bourgeois M. P. Carpenter R. M. Clark I. Deloncle R. Duffait J. Duprat K. Hauschild R. Henry R. V. F. Janssens M. J. Joyce T. L. Khoo M. Kaci T. Lauritsen Y. Le Coz M. Meyer E. S. Paul N. Perrin N. Poffé N. Redon C. Schück H. Sergolle J. F. Sharpey-Schafer J. Simpson A. G. Smith R. Wadsworth P. Willsau 《Zeitschrift für Physik A Hadrons and Nuclei》1994,347(3):223-224
New results on the192Hg superdeformed band have been obtained with EUROGAM. The experiment has been performed with the160Gd(36S,4n) reaction at 159 MeV. Above 800 keV the γ-ray energies differ from the previously published ones. Thus the rise of the dynamical moment of inertia $\mathfrak{F}^{(2)} $ above ?ω=0.4 MeV is no longer observed. This is in better agreement with recent cranked Hartree-Fock-Bogoliubov calculations. 相似文献
278.
Stephane Blouin Martin Guay Karen Rudie 《Central European Journal of Operations Research》2007,15(4):369-391
This article focuses on the dispatching problem of an oilsand excavation process subject to production objectives and specifications.
Herein, we cast the truck dispatching task in a decision-making framework for determining solutions and helping a dispatcher
to make decisions. In this paper, we apply the discrete-event formalism to investigate the dispatching of a large truck fleet.
For this purpose, we examine the capabilities and limitations of two distinct theories: discrete-event system (DES) and vector
discrete-event system (VDES). Despite their differences, both theories can be used to model the logical structure of the dispatching
process. These theories also provide techniques for implementing specifications and representing solutions in a compact manner.
The results of this paper demonstrate that current procedures and tools available for DES allow a broader range of techniques
to be applied, thus increasing the likelihood of finding a suitable solution.
This work was supported, in part, by the Natural Sciences and Engineering Research Council of Canada (NSERC), the Canadian
Foundation for Innovation and PRECARN and associates. In addition, the first author was supported by NSERC, Fonds pour la
formation de Chercheurs et l’Aide a la Recherche (FCAR), and Ontario Graduate Scholarships (OGS). 相似文献
279.
A way to study non-Gaussian measures is to generalize Schwartz's theory of Hilbertian subspaces to the non-Hilbertian case. We initiate here a new theory based upon a given duality rather than an Hilbertian structure. Hence, we develop the concept of subduality of a locally convex vector space and of its associated kernel. We show in particular that to any subduality is associated a unique kernel whose image is dense in the subduality. The image of a subdality under a weakly continuous linear application is also given, which enables the definition of a vector space structure over the set of subdualities given a equivalence relation. We then exhibit a canonical representative. Finally, we study the particular case of subdualities of endowed with the product topology. To cite this article: X. Mary et al., C. R. Acad. Sci. Paris, Ser. I 336 (2003). 相似文献
280.
Stephane Parola Roland Khem David Cornu Zian Kighelman Dragan Damjanovic Nava Setter 《Journal of Sol-Gel Science and Technology》2003,26(1-3):1109-1112
Pyrochlore free Pb(Mg1/3Nb2/3)O3 (PMN) thin films were prepared from mixed-metal precursors solutions using the sol-gel process. Lead acetate [Pb(CH3COO)2], magnesium acetate [Mg(CH3COO)2] and niobium ethoxide [Nb(C2H5O)5] were used as starting materials, while 2-isopropoxy-ethanol was chosen as solvent. The reactivity of the precursors was investigated in order to understand and control the process and thus to prevent the contamination of the PMN with the pyrochlore phase. The solution was spin-coated on TiO2/Pt/TiO2/SiO2/Si substrate. The thin films were characterized by SEM and XRD while dielectric measurements were performed on the bulk ceramic. 相似文献