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921.
Directed and elliptic flow for the 197Au+197Au system at incident energies between 40 and 150 MeV per nucleon has been measured using the INDRA 4π multi-detector. For semi-central collisions, the excitation function of elliptic flow shows a transition from in-plane to out-of-plane emission at around 100 MeV per nucleon. The directed flow changes sign at a bombarding energy between 50 and 60 MeV per nucleon and remains negative at lower energies. Molecular dynamics calculations (CHIMERA) indicate sensitivity of the global squeeze-out transition on the σ NN and demonstrate the importance of angular momentum conservation in transport codes at low energies.  相似文献   
922.
Epithio-substituted primary-tertiary dialkyl peroxides were prepared by treatment of tert-alkyl oxiranylmethyl peroxides with potassium thiocyanate and were tested as polymerization initiators in synthesis of light-resistant polystyrene.  相似文献   
923.
Surface morphology and catalytic properties of electrolytic silver crystals in partial oxidation of ethylene glycol into glyoxal were studied.  相似文献   
924.
925.
The inclusive reduced velocity correlation functions of the intermediate mass fragments were measured in the reactions of 36Ar + 112,124Sn at 35 MeV/u. The anti-correlation is observed to be stronger in 36Ar + 124Sn system than that in 36Ar + 112Sn. The difference of the correlation functions between the two reactions is mainly contributed by the particle pairs with high momenta. A three body Coulomb repulsive trajectory model is employed to calculate the emission time scale of the IMFs for the two systems. The time scale is 150 fm/c in 36Ar + 112Sn and 120 fm/c in the 36Ar + 124Sn, respectively.  相似文献   
926.
The objective of this paper is to analyze under what well-known operations the class of quasipolyhedral convex functions, which can be regarded as an extension of that of polyhedral convex functions, is closed. The operations that will be considered are those that preserve polyhedral convexity, such that the image and the inverse image under linear transformations, right scalar multiplication (including the case where λ=0+) and pointwise addition.   相似文献   
927.
This paper presents results of studies on dc electrical conductivity and transference number measurements on potassium bromate (KBrO3) complexed polyvinyl chloride (PVC) films prepared by solution cast technique. Temperature dependence of dc electrical conductivity and transference number data indicated the dominance of ion type charge transport in these specimens. The magnitude of conductivity increased with increase in concentration of the salt and temperature. Using this (PVC + KBrO3) electrolyte, solid-state electrochemical cells were fabricated, and their discharge profiles were studied under a constant load of 100 kΩ. Several cell profiles such as open circuit voltage, short circuit current, power density, and energy density associated with these cells were evaluated and were reported. The features of complexation of the electrolytes were studied by X-ray diffraction and Fourier transform infrared spectroscopy. Paper presented at the Third International Conference on Ionic Devices (ICID 2006), Chennai, Tamilnadu, India, Dec. 7–9, 2006  相似文献   
928.
引进了随机环境中多物种分枝随机游动的一般模型.在分枝过程非灭绝的情况下,讨论了系统的状态分类,得到了系统暂留及强常返的充要条件是存在k个定义在整数集上的函数分别满足某种性质.最后给出了系统强暂留的充分条件.  相似文献   
929.
The large deviation theorems, exponential inequalities and a non-uniform estimate of the Berry–Esséen theorem in a discounted version are proved.Dedicated to Professor Vytautas Statulevičius on the occasion of his 75th birthday.  相似文献   
930.
At ONERA-Lille center a lot of studies have been conducted to characterize complex flows using an optical method based on differential interferometry with Wollaston prism and white polarized light source. Several applications are presented in two-dimensional and axisymmetric flows and in a gaseous mixture where the two gases interface is submitted to acceleration. Then, real-time color holographic interferometry (RCHI) has been developed to obtain the refractive index itself in two dimensional wake flow. The last improvements concern the extension of this method for analyzing three dimensional flows. The authors present a specific setup defined in a single sight direction, the aim being to reproduce the same optical setup along several sight directions, each shifted by a given angle. This optical technique uses reflection holograms where the diffraction efficiency of plates is strongly influenced by the variations in the gelatin thickness produced during the holograms treatment. Problems are discussed and solutions are proposed to control the gelatin shrinkage for two different types of used holograms. The results obtained in a one sight direction make it possible to build in the future an optical setup allowing several simultaneous line-of-sight optical measurements.  相似文献   
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