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71.
methodology for bremsstrahlung (BS) background correction to extract a true Compton profile in high-energy Compton scattering
experiments is presented. The BS background profiles for Hg, computed within the Born approximation, are estimated for different
values of incident energy. It is seen for the first time that the BS background contribution in high-energy Compton profile
experiments like those employing third generation synchrotron radiation sources comes out to be significant and non-linear.
Further, it is found that the incorporation of BS correction in data reduction of such an experiment performed on Hg at 662
keV energy helps in reconciliation of theory and experiment. 相似文献
72.
Matrix element of the Galilean invariant non-relativistic reduction of the pseudoscalar-pseudovector interaction has been
calculated assuming the reaction to be a direct process with boundπ
− being absorbed by a correlated pair of nucleons. The Hartree-Fock wavefunctions obtained with the unitary-model-operator
approach starting with the realistic nucleon-nucleon interaction have been used forπ-capturing nucleon pair in the initial state. The calculations have been done with and without antisymmetrising the initial
state wavefunction of the pion absorbing pair. For the final state nucleon-nucleon interaction has been taken into account.
The strongπ-nucleus interaction together with the Coulomb interaction with the finite nuclear size on the bound pion wavefunction are
taken into account. Angular distributions of the emitted nucleon-pair, the branching ratios and the total absorption rates
are calculated for16O with and without antisymmetrisation effect. The calculated results are compared with the experimental and other theoretical
work. 相似文献
73.
The conservation of channel spin implying that the spin of the initial bound pair coupled to that of the initial free particle
should result in the same channel spin as the spin of the final bound pair coupled to the spin of the final free particle,
follows as a consequence of three-body theory of transfer reactions with the assumption of separability of two-bodyt-matrix. To test the validity of this principle we look at the experimental data on stripping reactions on even-even nuclei.
We find that although reactions to channels not conforming to channel spin conservation are not altogether ruled out, the
cross-sections of reactions violating channel spin conservation are much smaller than those conforming to channel spin conservation. 相似文献
74.
75.
76.
N.S. Ramegowda M.N. Modi A.K. Koul J.M. Bora C.K. Narang N.K. Mathur 《Tetrahedron》1973,29(23):3985-3986
Synthesis of certain aldehydes from the carboxylic acids has been carried by reduction of the corresponding N-acyl saccharins using SDA. The N-acyl saccharins are easily prepared by reaction of an acid with γ-saccharin chloride, which can be used for the next step of reduction without isolation and purification. This provides a convenient and one step synthesis of aldehydes by combining the two reactions, viz., preparation of the N-acyl compound and its reduction. The method has been successfully applied for the reduction of aliphatic, alicyclic, aromatic, and a α,β-unsaturated acids to the corresponding aldehydes and the yields obtained are quite satisfactory. 相似文献
77.
78.
A potentiometric titration with alkye nitrite solutions is described for the determination of various sulpha, drugs. 相似文献
79.
80.
G.A. Royce V.K. Mathur R.J. Abbundi M.D. Brown J.J. Fontanella M.C. Wintersgill 《Journal of luminescence》1984,29(2):205-213
A study was conducted of the effects of gamma radiation on samarium (Sm)-doped calcium flouride (CaF2) crystals. Optical absorption measurements indicate that many of the Sm3+ ions are converted to Sm2+ during irradiation. Heavy doses of 106 rad also modify the trapping structures and enhance certain defects within the crystals. A comparison is provided between unirradiated and heavily irradiated CaF2 crystals with three Sm concentrations: 0.01, 0.1, and 1.0 molar-percent. Thermoluminescence measurements indicate that the crystals with high Sm content provide less luminescence and that the activation energy is less than seen in the 0.01 molar-percent Sm crystals. 相似文献