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61.
B. O. Bateup J. R. Cook H. D. Feldtman und B. E. Fleichfresser 《Colloid and polymer science》1978,256(4):416
Ohne Zusammenfassung 相似文献
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.
William Cook 《Operations Research Letters》1983,2(1):31-35
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.
Wayne D. Cook 《European Polymer Journal》1978,14(9):721-727
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.
66.
67.
R. J. Cook 《Israel Journal of Mathematics》1974,19(4):349-358
Mahler obtained inequalities relating an0-symmetric convex body with its compounds. These results are extended to asymmetric convex bodies. 相似文献
68.
Michael J. Cook Ghoabad Ghaem-Maghami Festus Kaberia Knut Bergesen 《Magnetic resonance in chemistry : MRC》1983,21(5):339-343
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
69.
Andrew V. Chapman Michael J. Cook Alan R. Katritzky Michael H. Aabraham Angela F. Danil De Namor Lilane Dumont Jacques Reisse 《Tetrahedron》1978,34(10):1571-1575
The dehydration of various 4,5-dihydro-4- and -5-hydroxy derivatives of pyrazole and isoxazole has been investigated. Heats of dehydration of 4,5-duiydro-4-hydroxy-1,3,5-tripbenylpyrazole and 4,5-dihydro-5-hydroxy-isoxazole are evaluated and used to assess the empirical resonance energy and conjugation energy of pyrazole and isoxazole. The former possesses resonance stabilisation comparable to pyrrole but that of the latter is low. 相似文献
70.
Recent proposals for using plasma wakefield accelerators (PWFA) as a component of a linear collider have included intense electron beams with densities many times in excess of the plasma density. The beam's electric fields expel the plasma electrons from the beam path to many beam radii in this regime. We analyze here the motion of plasma ions under the beam fields, and find for a proposed PWFA collider scenario that the ions completely collapse inside of the beam. Simulations of ion collapse are presented. Implications of ion motion on the feasibility of the PWFA-based colliders are discussed. 相似文献