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31.
Rene Bellwied 《Acta Physica Hungarica A》2004,21(2-4):199-205
Nuclear suppression factor and u 2 measurements as a function of transverse momentum for neutral strange particles are shown and compared to particle identified spectra from PHENIX and WA98 and to models that attempt to describe the suppression of particles at moderate pt in central RHIC Au?Au collisions. It is shown that identified spectra carry additional information to the published charged particle spectra. In particular, dependencies of the R AA and u 2 values on the measured particle species will be discussed in the context of several models. 相似文献
32.
Jean Sala-Pala Jacques Amaudrut Jacques E. Guerchais Rene Mercier Jacques Douglade Jean Gerard Theobald 《Journal of organometallic chemistry》1980,204(3):347-359
Hexafluorobutyne (CF3CCCF3 = Hfb) reacts with Cp2NbH3 (Cp = η5-C5H5) affording five new complexes I–V, whose structures have been studied by mass, Ir, ESR and NMR spectroscopy. The X-ray study of II shows the presence of a planar NbC4 ring Nb—C(1): 2.25(5); C(1)—C(2): 1.31(7); C(2)—C(3): 1.53(8); C(3)—(4): 1.34(7); C(4)—Nb: 2.23(5) Å. With trifluoropropyne (CF3CCH = tfp), only the analog of III, i.e. Cp2NbFf(tfpH), has been isolated. 相似文献
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Forrer J Schmutz H Tschaggelar R Schweiger A 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2004,166(2):220-251
Direct detection of free induction decays and electron spin echoes, and the recording of echo-detected EPR spectra and electron spin echo envelope modulation patterns at a microwave frequency of 2.5 GHz is demonstrated. This corresponds to the measurement of the transverse magnetization in the laboratory frame, rather than in the rotating frame as usually done by down-converting the signal (homodyne detection). An oscilloscope with a 6-GHz analog bandwidth, a sampling rate of 20 GigaSamples per second, and a trigger frequency of 5 GHz for the edge trigger and 750 MHz for the advanced trigger, is used in these experiments. For signal averaging a 3-GHz microwave clock divider has been developed to synchronize the oscilloscope with the frequency of the EPR signal. Moreover, direct detection of continuous wave EPR signals at 2.5 GHz is described. 相似文献
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Rene Y. Darmon 《The Journal of the Operational Research Society》1987,38(12):1121-1132
This paper describes an IBM-PC menu-driven and user-friendly procedure which can help sales management in setting up optimal quota-bonus plans. For a given sales force, the resulting quotabonus plan maximizes the firm's current profits subject to (1) keeping every individual sales-force member at least at his/her current level of satisfaction (or eventually, increasing this level), and (2) being consistent and harmonious across sales representatives. The QUOPLAN system is composed of two submodels. The first submodel is used by salespersons for eliciting their own utility functions, and is essentially based upon the principles of conjoint analysis. The second submodel is used by management for reconciling all the individuals' judgements and the company's objectives into a consistent quota-bonus plan. 相似文献
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Summary We give a general construction of infinite dimensional Ornstein-Uhlenbeck processes. We present expansions of these processes based on the expansion of the covariance operators in generalized eigenfunctions, and we answer positively some question left open by J.B. Walsh on properties of the hitting times of these processes.Partially supported by NSF-Grant MCS 8202045 相似文献
39.
Sebastian Gatz Helge Hannebauer Rene Hesse Florian Werner Arne Schmidt Thorsten Dullweber Jan Schmidt Karsten Bothe Rolf Brendel 《固体物理学:研究快报》2011,5(4):147-149
We demonstrate industrially feasible large‐area solar cells with passivated homogeneous emitter and rear achieving energy conversion efficiencies of up to 19.4% on 125 × 125 mm2 p‐type 2–3 Ω cm boron‐doped Czochralski silicon wafers. Front and rear metal contacts are fabricated by screen‐printing of silver and aluminum paste and firing in a conventional belt furnace. We implement two different dielectric rear surface passivation stacks: (i) a thermally grown silicon dioxide/silicon nitride stack and (ii) an atomic‐layer‐deposited aluminum oxide/silicon nitride stack. The dielectrics at the rear result in a decreased surface recombination velocity of Srear = 70 cm/s and 80 cm/s, and an increased internal IR reflectance of up to 91% corresponding to an improved Jsc of up to 38.9 mA/cm2 and Voc of up to 664 mV. We observe an increase in cell efficiency of 0.8% absolute for the cells compared to 18.6% efficient reference solar cells featuring a full‐area aluminum back surface field. To our knowledge, the energy conversion efficiency of 19.4% is the best value reported so far for large area screen‐printed solar cells. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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