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91.
Hafez S. Abdel Wahab J. Bérczi L. Bognár G. Keömley 《Journal of Radioanalytical and Nuclear Chemistry》1977,36(2):479-490
Twelve zircon samples representing different genetic types from Australia, China, Egypt, Hungary, Korea and Nigeria were examined
using the neutron activation techniques. The study of the trace elements encountered in zircons, especially Zr/Hf ratios,
shed the light on the type of zircon minerals as well as the mother rock from which zircons wrre separated. Furthermore, the
effect of the secondary processes on zircons and their host rocks were also studied. 相似文献
92.
Zusammenfassung Es wird ein zweites graphisches Verfahren dargestellt, welches gestattet, die Viskosität zäher Flüssigkeiten zu ermitteln. 相似文献
93.
Transition boiling curves of distilled water on Inconel surfaces under forced convective conditions have been obtained. These data were generated from Inconel-copper composite test sections during quench experiments, using two-dimensional analysis. In order to properly account for axial conduction in the composite test sections, the two-dimensional model should be employed. An empirical correlation has been proposed, based on previous and present data. 相似文献
94.
Excitation functions for proton elastic scattering on Mn55 at proton energies from 1320 KeV to 1480 KeV have been measured at the angles 135° and 150°. Anomalies in the differential elastic scattering were observed at Ep = 1350 ± 4 KeV, 1385 ± 4 KeV and 1445 ± 4 KeV respectively. These resonance states are the isobaric analogues of the ground, first excited and second excited states in Mn56 respectively. Analysis of the results showed that these resonance states are best fitted to a Jπ = 3+, 2+ and 1+ which is in excellent agreement with the Jπ values of the corresponding states in Mn56. The total widths and proton widths of these states were determined. 相似文献
95.
96.
A. EL-Depsy D.A. Gharbiea M.S. Abdel Krim 《Journal of Quantitative Spectroscopy & Radiative Transfer》2006,98(3):379-393
The Milne problem is investigated subject to reflecting boundary conditions. The original version of the problem with vacuum boundary condition is generalized assigning, to the surface x=0, a specular reflection coefficient . Linearly anisotropic case is studied. The integral version of the transport equation solved using trial functions based on Case's eigenvalues and exponential integral function. Solution of the Milne problem is formulated in terms of characteristic parameters such as extrapolated end point, emergent angular distribution and total neutron density. Numerical results for the analytically evaluated parameters are then present. Some of our numerical results are compared with the available published results. 相似文献
97.
Hayer A de Halleux V Köhler A El-Garoughy A Meijer EW Barberá J Tant J Levin J Lehmann M Gierschner J Cornil J Geerts YH 《The journal of physical chemistry. B》2006,110(15):7653-7659
A concept for highly ordered solid-state structures with bright fluorescence is proposed: liquid crystals based on tetraethynylpyrene chromophores, where the rigid core is functionalized with flexible, promesogenic alkoxy chains. The synthesis of this novel material is presented. The thermotropic properties are studied by means of differential scanning calorimetry (DSC), cross-polarized optical microscopy (POM), and X-ray diffraction. The mesogen possesses an enantiotropic Col(h) phase over a large temperature range before clearing. The material is highly fluorescent in solution and, most remarkably, in the condensed state, with a broad, strongly red shifted emission. Fluorescence quantum yields (Phi(F)) have been determined to be 70% in dichloromethane solution and 62% in the solid state. Concentration- and temperature-dependent absorption and emission studies as well as quantum-chemical calculations on isolated molecules and dimers are used to clarify the type of intermolecular interactions present as well as their influence on the fluorescence quantum yield and spectral properties of the material. The high luminescence efficiency in the solid state is ascribed to rotated chromophores, leading to an optically allowed lowest optical transition. 相似文献
98.
We consider an n-player non-cooperative game with random payoffs and continuous strategy set for each player. The random payoffs of each player are defined using a finite dimensional random vector. We formulate this problem as a chance-constrained game by defining the payoff function of each player using a chance constraint. We first consider the case where the continuous strategy set of each player does not depend on the strategies of other players. If a random vector defining the payoffs of each player follows a multivariate elliptically symmetric distribution, we show that there exists a Nash equilibrium. We characterize the set of Nash equilibria using the solution set of a variational inequality (VI) problem. Next, we consider the case where the continuous strategy set of each player is defined by a shared constraint set. In this case, we show that there exists a generalized Nash equilibrium for elliptically symmetric distributed payoffs. Under certain conditions, we characterize the set of a generalized Nash equilibria using the solution set of a VI problem. As an application, the random payoff games arising from electricity market are studied under chance-constrained game framework. 相似文献
99.
This paper applied the modified variational iteration method to the nonlinear coupled partial differential equations via the
generalized nonlinear Hirota Satsuma coupled KdV equations, the nonlinear coupled Kortewge–de Vries KdV equations and the
nonlinear shallow water equations together with the initial conditions. The proposed modification is made by introducing Adomian’s
polynomials in the correct functional. The suggested algorithm is quite efficient and is practically well suited for use in
such problems. The proposed iterative scheme finds the solution without any discritization, liberalization, perturbation,
or restrictive assumptions. 相似文献
100.
Ali Emrouznejad Abdel Latef Anouze Emmanuel Thanassoulis 《European Journal of Operational Research》2010
Data Envelopment Analysis (DEA) is a nonparametric method for measuring the efficiency of a set of decision making units such as firms or public sector agencies, first introduced into the operational research and management science literature by Charnes, Cooper, and Rhodes (CCR) [Charnes, A., Cooper, W.W., Rhodes, E., 1978. Measuring the efficiency of decision making units. European Journal of Operational Research 2, 429–444]. The original DEA models were applicable only to technologies characterized by positive inputs/outputs. In subsequent literature there have been various approaches to enable DEA to deal with negative data. 相似文献