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101.
M. Pârlog G. Tăbăcaru J. P. Wieleczko J. D. Frankland B. Borderie A. Chbihi M. Colonna M. F. Rivet 《The European Physical Journal A - Hadrons and Nuclei》2005,25(2):223-228
Stochastic mean-field simulations for multifragmenting sources at the same excitation energy per nucleon have been performed. The freeze-out volume, a concept which needs to be precisely defined in this dynamical approach, was shown to increase as a function of three parameters: freeze-out instant, fragment multiplicity and system size. 相似文献
102.
D. Pierroutsakou M. Di Toro F. Amorini V. Baran A. Boiano A. De Rosa A. D'Onofrio G. Inglima M. La Commara A. Ordine N. Pellegriti F. Rizzo V. Roca M. Romoli M. Sandoli M. Trotta S. Tudisco 《The European Physical Journal A - Hadrons and Nuclei》2003,16(3):423-435
We report on the results obtained from the study of the 32S + 64Ni and 32S + 58Ni peripheral reactions at incident energies E
lab = 288 MeV and E
lab = 320 MeV, respectively. High-energy γ-rays were detected in an array of 8 seven-pack BaF2 clusters. Coincidence with complex fragments detected in 12 three-stage telescopes ensured the selection of peripheral reaction
events. All of the relevant reaction parameters were kept constant with the exception of the different initial dipole moment
caused by the different entrance channel charge asymmetry. While for quasi-elastic events no N/Z effect was observed in the differential γ-ray multiplicities of the two reactions, for deep-inelastic events a larger dipole
γ-ray emission occurs during the more N/Z asymmetric reaction. A theoretical interpretation based on a collective Bremsstrahlung analysis of the reaction dynamics
is presented.
Received: 26 September 2002 / Accepted: 13 November 2002 / Published online: 6 March 2003
RID="a"
ID="a"e-mail: pierroutsakou@na.infn.it
RID="b"
ID="b"Present address: INFN, Laboratori Nazionali di Legnaro, Padova, Italy.
Communicated by C. Signorini 相似文献
103.
A. S. Tikhomirov 《Acta Appl Math》2003,75(1-3):271-279
We study the moduli scheme M(2;0,n) of rank-2 stable vector bundles with Chern classes c
1=0, c
2=n, on the Fano threefold X – the double space P
3 of index two. New component of this scheme is produced via the Serre construction using certain families of curves on X. In particular, we show that the Abel–Jacobi map :HJ(X) of any irreducible component H of the Hilbert scheme of X containing smooth elliptic quintics on X into the intermediate Jacobian J(X) of X factors by Stein through the quasi-finite (probably birational) map g:M of (an open part of) a component M of the scheme M(2;0,3) to a translate of the theta-divisor of J(X). 相似文献
104.
文章主要介绍几种蛋白质空间结构的实验测定方法,在现代生物学研究中,最常用的方法包括X射线晶体学、二维核磁共振(2D-NMR)和低温冷冻电镜,近几年发展起来的单分子技术在生物大分子动态结构的研究中应用越来越多,这些方法都有它们特定的时间和空间分辨率,所测定的结构及其动力学受环境热运动涨落的影响也非常不同,文章对这些问题作了较详细的分析,在蛋白质结构的理论方法方面,介绍了一个新的折叠理论及其与现有折叠模型的关系.讨论了模拟计算在研究蛋白质构象变化和动力学方面的应用,同时强调了分子动力学和蒙特卡罗方法.指出粗粒化模型是研究的热点之一,对生物学中经常遇到的多长度多时问尺度问题提供了一个可行的解决方案。 相似文献
105.
G. García E. Mejía-Ospino A. Guerrero I. Álvarez C. Cisneros 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,42(3):393-396
The kinetic energy release distributions (KERDs) of
C+ and O+ fragments arising from 5 keV collision-induced
dissociation (CID) of CO+ ions with helium have been measured. The
KERDs of C+ and O+ exhibit different features corresponding to the
states that participate in CID processes. We have identified groups of
dissociative and predissociative states, and compare them with theoretical
and experimental values. 相似文献
106.
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
107.
108.
109.
Duangkamol Gleeson 《Journal of Chemometrics》2008,22(6):372-377
Reported herein are the results of an investigation into the effect of the extended framework of the zeolite ZSM‐5 on the reaction energetics and structures of (a) the physisorbed complex formed between the zeolite and six alkenes, (b) the corresponding chemisorbed alkoxide intermediate and (c) the transition states (TS) connecting the two. For this, quantum mechanical (QM) simulations of ZSM‐5 in the presence and absence of the zeolite framework have been employed. A 46T density functional theory (DFT) cluster model and a 3T:46T DFT:UFF ONIOM model are used to represent the former scenario and a simple 3T DFT cluster model for the latter. The structural implications of neglecting the zeolite framework have been rigorously compared using the multivariate statistical method principal components analysis (PCA). This method allows one to assess the correlated nature of the changes in structure along the reaction coordinate, for multiple different alkenes, in a facile, reliable way. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
110.
Kazuhiro Higuchi 《Tetrahedron》2010,66(6):1236-6033
A novel preparative method for 2,2-disubstituted 1,2-dihydro-3H-indol-3-ones through the oxidation of 2-arylindoles followed by a Mannich-type reaction with carbon nucleophiles is described. 相似文献