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31.
We carry out a systematic study of the different contributions to the deviations of the elliptic flows from the quark number scaling in high energy heavy ion collision in a quark combination model.The effects that we considered are:the resonance decay,the flavor dependence of the quark elliptic flow and the combination of quarks/antiquarks with slightly different transverse momenta.Our results show that the deviations observed in experiments can be well reproduced within the combination framework if all the three effects are considered. We make a detailed analysis of the different contributions using a Monte-Carlo program and suggest measuring the quark number scaling in intermediate pT range more precisely. 相似文献
32.
L. Lammich S. Altevogt H. Buhr H. Kreckel S. Krohn M. Lange D. Strasser R. Repnow M. Grieser R. Schinke Z.-W. Qu H. Zhu D. Schwalm D. Zajfman A. Wolf 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,41(1):103-111
The fragmentation of LiH2
- anions after electron
impact was investigated at the heavy-ion storage ring TSR.
The main reaction channel was found to be electron detachment followed by a
breakup into LiH + H.
In the first ms after production of the molecular ions in a cesium
sputtering ion source, additional
contributions were observed in the Li + H2 and Li- + H2 channels,
hinting at an initial population of a short-lived state of the anion.
To gain a better understanding of the mechanisms underlying the observed
behavior of the system, ab initio calculations of relevant potential
energy surfaces were performed at selected geometries.
The experimental findings are discussed in the
light of these calculations. 相似文献
33.
新型高效太阳能电池研究进展 总被引:1,自引:0,他引:1
第三代太阳能电池以超高效率、薄膜化、低成本为主要目标,目前发展起来的有多结叠层太阳能电池、中间带太阳能电池、多激子产生太阳能电池、热载流子太阳能电池和热光伏太阳能电池等.文章简要介绍了以上几种新型太阳能电池的工作原理和最新进展,并对其发展前景作了分析和预测. 相似文献
34.
35.
We show, using semiclassical methods, that as a symmetry is broken, the transition between universality classes for the spectral
correlations of quantum chaotic systems is governed by the same parametrization as in the theory of random matrices. The theory
is quantitatively verified for the kicked rotor quantum map. We also provide an explicit substantiation of the random matrix
hypothesis, namely that in the symmetry-adapted basis the symmetry-violating operator is random. 相似文献
36.
Intermediate processes and critical phenomena: Theory, method and progress of fractional operators and their applications to modern mechanics 总被引:1,自引:0,他引:1
From point of view of physics, especially of mechanics, we briefly introduce fractional operators (with emphasis on fractional
calculus and fractional differential equations) used for describing intermediate processes and critical phenomena in physics
and mechanics, their progress in theory and methods and their applications to modern mechanics. Some authors’ researches in
this area in recent years are included. Finally, prospects and evaluation for this subject are made. 相似文献
37.
Novel interconnection scheme for thin‐film silicon solar modules with conductive intermediate reflector 下载免费PDF全文
Bugra Turan Andreas Bauer Andreas Lambertz Tsvetelina Merdzhanova Stefan Haas 《固体物理学:研究快报》2015,9(2):103-107
Intermediate reflector layers are commonly used for light man‐agement purposes in multi‐junction silicon based devices containing a‐Si:H top‐ and µc‐Si:H bottom‐sub‐cells. A low resistance of such layers can have a severe impact on the solar module performance due to shunting of the bottom sub‐cell by the P2 scribe. A common solution for this problem is the use of an additional scribe line. However, not only the additional processing step is disadvantageous but also the dead area losses are increased as well by the additional scribe. This work introduces a novel solar cell stripe interconnection scheme that requires only three scribing processes with similar dead area losses as they would be apparent in the standard interconnection scheme. An implementation to mini modules shows no negative impact on the electrical properties and simultaneously reducing the required number of scribing steps. (© 2015 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim) 相似文献
38.
39.
Chunying Ma Yixuan Zheng Jinwei Liu Xiaobao Li Wenhua Feng 《Molecules (Basel, Switzerland)》2022,27(6)
The key intermediate NH2-Ile-Thr(Bzl)-Asn-Cys(Bzl)-Pro-COOH of Atosiban was prepared from N-Boc-S-Bzl-cysteine by the stepwise lengthening of the chain according to the repetitive N,O-bis(trimethylsilyl)acetamide/N-hydroxysuccinimide ester (BSA/NHS) strategy. This synthetic route required no chromatography purification and can be readily performed, yielding a highly pure pentapeptide compound. 相似文献
40.
Theoretical investigations of InGaN tandem solar cells with intermediate bands (IBs) have been conducted through calculating the diode equation taking into account the radiative and nonradiative recombination currents. The calculated maximum ef?ciencies of the double‐junction cell with one IB in each subcell are 57.85% and 68.37% under AM1.5G one‐sun and 46000‐sun illuminations, respectively. It has also been observed that the combined device with the top‐cell bandgaps of 2.9–3.4 eV (2.6–3.4 eV for full concentration) may have an opportunity to realize the application of over 50% efficiency. We suggest that the optimized width of the IB layer be designed in the range of 1–6 μm if its absorption coefficient is 104–105 cm–1 in the IB region. 相似文献