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61.
62.
J. Cook 《Nuclear Physics A》1982,375(2):238-262
The energy dependence of 6Li optical potentials for elastic scattering from 28Si, 40Ca, 58Ni, 90Zr and 208Pb targets has been investigated by simultaneously fitting several data sets over a wide energy range. Both Saxon-Woods and double-folded real potentials have been used. In general, there is no requirement for energy dependence in either the real or imaginary potential for any of these targets, whether Saxon-Woods or folded real potentials are used. The main exception is 28Si when energy dependence is required to simultaneously fit low-energy data and high-energy rainbow scattering with folded potentials. The degree to which the potentials are determined is discussed.  相似文献   
63.
There are many useful operations, such as adding slack variables, taking scalar multiples of inequalities, and applying Fourier-Motzkin elimination, that can be performed on a linear system such that if the system defines an integer polyhedron then so does the derived system. The topic dealt with here is whether or not these operations also preserve total dual integrality of linear systems.  相似文献   
64.
The equation of rubber elasticity has been applied to the dynamic shear modulus of styreneunsaturated polyester networks. Due to the non-ideal nature of the networks, the apparent front factor approached the theoretical value of 0.5 only when the crosslink density was low. At higher crosslink densities, it has been found that either the non-Gaussian theory of Smith or the steric interaction approach of Blanchard and Wooton satisfactorily describes the results.  相似文献   
65.
A facile method for the preparation of the aromatic pyrrolo[1,5-b:2,3-c']dipyridazine ring system is reported. A number of compounds have been prepared and the biological screening data reported.  相似文献   
66.
A wavefunction used in an earlier calculation of the nuclear shielding of the hydrogen molecule has been tested by comparing the calculated magnetic susceptibility against that of Kolos and Wolniewicz. Good agreement is obtained. The procedure of Herman and Short for averaging over the nuclear motion has also been tested by comparing the predicted susceptibilities of H2, Hd and D2 with those obtained from averages of the Rydberg-Klein-Rees potential curves by Jain and Sahni. Again, good agreement is found.For the first time calculated values have been obtained for the susceptibilities of the isoropomers of hydrogen which contain tritium. It is predicted that accurate susceptibility measurements should not only be able to distinguish between all the various isotopomers but should also detect the temperature dependence of the susceptibility of any one isotopomer.  相似文献   
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Mahler obtained inequalities relating an0-symmetric convex body with its compounds. These results are extended to asymmetric convex bodies.  相似文献   
70.
1H NMR Parameters are reported for five 1,4-dithiepan-6-ones. 1,4-Dithiepan-6-one 1-oxide exists in solution as an equilibrium involving two different twist-chair conformations, which contrasts with its conformational behaviour in the solid state. Twist-chair conformers are also adopted by other members of the series, the favoured form varying with ring substitution. The S?O bond in 1,4-dithiepan-6-one 1-oxide and in its 5,5-dimethyl analogue exhibit a preference for the pseudoaxial site.  相似文献   
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