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131.
132.
Cross sections have been measured for the elastic and inelastic scattering of electrons from 70Ge and 72Ge for momentum transfers from 0.65 to 1.14 fm?1. Values for the parameters of a Fermi type ground-state charge distribution were obtained from a phase shift analysis of the elastic cross sections. The rms charge radius corresponding to these parameters is 4.07±0.02 fm for 70Ge and 4.05±0.03 fm for 72Ge. Using DWBA analysis the reduced transition probabilities for the electroexcitation of the 21+ and 31? states were found to be: B(E2, ω)↑ = 19.7±1.2, 26.8±2.0 W.u.; B(E3, ω)↑ = 36±5, 37±7 W.u. for 70Ge and 72Ge respectively. The Jπ = 3? assignments for the state at 2.562 MeV in 70Ge and 2.515 MeV in 72Ge are confirmed. 相似文献
133.
Allen C. Cogley Robert W. Bergstrom 《Journal of Quantitative Spectroscopy & Radiative Transfer》1979,21(3):263-278
A recent formulation in radiative transfer defined the thermal scattering functions that characterize radiative transfer from a general, plane-parallel, finite medium driven solely by an internal distribution of thermal sources. Exiting diffuse intensities are expressed as space convolutions of the thermal scattering functions with any thermal source distribution. A parametric study is presented to obtain the basic structure of these scattering functions. The independent variables of these azimuthally independent functions are the direction consine μ and source location t, while the parameters are the single scattering albedo ω, total optical depth t0, and the asymmetry factor g in the Henyey-Greenstein phase function. The basic functional trends are discussed using various parametric plots, and selected tabular results are given to allow numerical checks. The computational method is invariant imbedding. As a particular application, these functions are used in the following companion paper to obtain exiting intensities from inhomogeneous and nonisothermal media. 相似文献
134.
Abstract— The photosensitization of some biomolecules by proflavine was studied using the technique of electron paramagnetic resonance. It was shown that this process is directly influenced by the relative molar concentration of dye and substrate. For some values of these concentrations, a singlet associated with a radical form of proflavine is observed. The appearance of this signal is discussed in terms of electron transfer from an ionized proflavine molecule directly to another neutral dye molecule or via a molecule of substrate as an intermediate. It is shown that this transfer is facilitated by stacking. These results were compared with radiolysis of the same kind of complexes in frozen aqueous solution. 相似文献
135.
The form factor ofthe 3.56MeV(0+, T = 1) state of 6Li has been measured for momentum transfers q = 1.0–3.0 fm?1, and the and states have been measured up to q = 2.5 fm?1. The 3.56 MeV form factor is analysed in terms of a phenomenological shell model with l = i valence nucleons. The radial wave functions are found to have a greater radial distribution than given by the harmonic oscillator, more closely resembling Woods-Saxon functions. The M1 form factor is found to decrease at high momentum transfer somewhat more slowly than the models predict. A technique for determining the Mλ transition current density based on the Fourier-Bessel analysis is developed and applied to the M1 transition. The M1 transition current density is obtained within a moderate error band and compared with the harmonic oscillator and Woods-Saxon densities. The M1 radiative width is 8.18 ± 0.25 eV, in agreement with previous measurements. 相似文献
136.
A new multiblock unfactored implicit upwind scheme for inviscid two-dimensional flow calculations is presented. Spatial discretization is carried out by means of an upwind first-order method; an original extension to higher accuracy is also presented. The integration algorithm is constructed in a ‘δ’ form that provides a direct derivation of the scheme and leads to an efficient computational method. Fast solutions of the linear systems arising at each time step are obtained by means of the bi-conjugate gradient stabilized technique. The computational results for super/hypersonic steady state flows illustrate the efficiency and accuracy of the algorithm. 相似文献
137.
S.I.S.向量随机测度在弱拓扑及相容拓扑下的收敛性 总被引:1,自引:0,他引:1
本文主要研究s.i.s.向量随机测度在弱拓扑及相容拓扑下的收敛性,给出了s.i.s.向量随机测度在弱拓扑 容拓扑下的Vitali-Halm-Saks定理,作为应用,我们建立了R^1-值有界可测函数关于Banach空间值s.i.s.向量随机测度的随机积分的收敛定理,并得到了具typep的Banach空间中s.i.s.向量随机测度的大数定律及中心极限定理。 相似文献
138.
LUCINIO JÚDEZ ROSARIO DE ANDRÉS MIGUEL IBÁÑEZ ELVIRA URZAINQUI 《Natural Resource Modeling》2011,24(3):297-315
Abstract This paper aims to determine the minimum agri‐environmental premium per hectare that farmers should receive to reduce crop irrigation. To this end, the authors develop a mixed‐integer quadratic model using a new methodology based on traditional positive mathematical programming, which allows the inclusion in the model of crop variants that are not present in the baseline situation of the farms. What is shown is that the results obtained with this new methodology, using the cost average approach of calibration, are the same as those obtained with an empirical method, when there is no change of crop distribution after the changeover from irrigated to nonirrigated farms. The theoretical results are compared with those obtained using the calibration with exogenous elasticities and are illustrated numerically for a representative farm of an area around Spain's Tablas de Daimiel in which the use of groundwater for crop irrigation has led to the ongoing deterioration of wetlands that depend on the same source of water, endangering the region's environmental sustainability. 相似文献
139.
Polymorphic optical networks simultaneously support several optical switching paradigms over a single physical network. In this way, they provide service differentiation at the optical layer by employing the most appropriate paradigm for each service. One type of such architecture is the optical circuit-switched polymorphic network (OCSPN), which combines optical circuit switching paradigms with different grades of dynamism. The performance of this network relies on the utilization of efficient routing and wavelength assignment (RWA) algorithms. In this article, we review the fundamentals of OCSPNs and present a set of efficient RWA algorithms based on ant colony optimization and genetic algorithms. 相似文献
140.
Existing methods for predicting resource divisions in laboratory exchange networks do not take into account the sequential nature of the experimental setting. We extend network exchange theory by considering sequential exchange. We prove that Sequential Power-Dependence Theory—unlike Power-Dependence Theory and most other exchange theories—has a unique point prediction for resource divisions in every network, and we show that these point predictions fare well in comparison to those from established theories. 相似文献