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51.
Kulwant Singh Gagandeep Kaur G. K. Sandhu B. S. Lark 《Radiation Physics and Chemistry》2001,61(3-6):537-540
The linear attenuation coefficients in aqueous solutions of some chlorides and sulphates, viz. MgCl2·6H2O, CaCl2, SrCl2·6H2O, BaCl2·2H2O, Na2SO4, K2SO4 and MgSO4·7H2O were determined at 81, 356, 511, 662, 1173 and 1332 keV by the γ-ray transmission method in a good geometry setup. From the precision measured densities of these solutions, mass attenuation coefficients were then obtained which varied systematically with the corresponding changes in the concentrations (g/cm3) of these solutions. A comparison between experimental and theoretical values of attenuation coefficients has shown that the study has potential application for the determination of attenuation coefficients of solid solutes from their solutions without obtaining them in pure crystalline form. 相似文献
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Romesh Chandra Boruah Purabi Devi J. S. Sandhu 《Journal of heterocyclic chemistry》1979,16(8):1555-1557
Some 7-melhyl-substituted-2,1-benzisoxazoles and cyclopropanobenzofurazan oxides are synthesized and characterized by their elemental and spectral analyses. 相似文献
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55.
We calculate the neutron-evaporation residue cross sections σ 3n , σ 4n , and σ 5n in the hot-fusion reactions 48Ca+242,244Pu →290,292114 ? over a wide range of compound-nucleus excitation energies ( $E_{\text{CN}}^{*}$ = 34–53 MeV). We work with the dynamical cluster-decay model (DCM), with a single parameter, the neck-length parameter ΔR. To calculate neutron-evaporation cross sections, we choose the superheavy proton magic Z = 126 and neutron magic N = 184. Among the 3n, 4n, and 5n production cross sections for 290, 292114?, only the 3n decay cross sections of 292114? correspond to spherical fragmentation. The 4n and 5n cross sections of 292114? and 3n, 4n, and 5n cross sections of 290114? could only be fitted after the inclusion of quadrupole deformations β 2i within the optimum orientation approach. Changes in the angular momentum and N/Z ratio do not significantly influence the fragmentation paths of 290, 292114? superheavy nuclei. Larger barrier modification is required for the lower angular momentum states and lighter neutron clusters. The contribution of the fusion–fission component is also computed for the compound nucleus 292114? in the energy range $E_{\text{CN}}^{*}$ = 27–47 MeV. 相似文献
56.
Huo Y Sandhu S Pan J Stuhrmann N Povinelli ML Kahn JM Harris JS Fejer MM Fan S 《Optics letters》2011,36(8):1482-1484
We measure the group delay in an on-chip photonic-crystal device with two resonators side coupled to a waveguide. We demonstrate that such a group delay can be controlled by tuning either the propagation phase of the waveguide or the frequency of the resonators. 相似文献
57.
Studies on pyrimidine derivatives. Michael addition of β-nitrostyrenes to substituted 6-aminouracils
A series of 5-(2-nitro-l-phenyl)ethyluracils were obtained when β-nitrostyrenes were reacted with 1,3-di-methyl-6-substituted uracil derivatives, instead of cyclic compounds. The structures of the compounds 5, 6 , and 7 were proved by spectroscopic methods and their mass fragmentation patterns are discussed. 相似文献
58.
M. P. Singh Amandeep Sharma Bhajan Singh B. S. Sandhu 《Journal of Radioanalytical and Nuclear Chemistry》2014,302(1):187-194
The effective atomic numbers of composites and Rayleigh-to-Compton cross-section ratio of elements, in the range 6 ≤ Z ≤ 82 for 145 keV gamma photons, are determined experimentally. An HPGe (high purity germanium) semiconductor detector is placed, at scattering angle of 90°, to record the spectra originating from interactions of incident gamma photons with the target under investigations. The intensity ratio of Rayleigh-to-Compton scattered peaks, corrected for photo-peak efficiency of gamma detector and absorption of photons in the target and air column, is plotted as a function of atomic number and a best fit-curve is constituted. From this fit-curve, the respective effective atomic numbers of the scientific samples are determined. The measured values of cross-section ratio increases non-linearly with increase in atomic number and are found to agree with theoretical predictions based upon non-relativistic form factor, relativistic form factor, modified form factor and S-matrix theory. 相似文献
59.
Patel VB Sandhu G Corbett JM Dunn MJ Rodrigues LM Griffiths JR Wassif W Sherwood RA Richardson PJ Preedy VR 《Electrophoresis》2000,21(12):2454-2462
We investigated whether the imposition of chronic alcohol in hypertension leads to greater biochemical and cellular abnormalities of the myocardium than those arising in normotension. Fifteen-week-old spontaneously hypertensive rats (SHR) and Wistar Kyoto (WKY) rats were fed ethanol-containing diets for six weeks. Particular attention was focused on the composition of contractile proteins identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), fractional rate of protein synthesis, and synthesis rates relative to RNA (RNA activity) or DNA (cellular efficiency). In addition, myocardial enzymes and adenine nucleotides were measured. In both SHR and WKY rats chronic ethanol caused a general decrease in the contents of all nine contractile proteins with myosin heavy chain predominantly affected. Fractional rates of mixed (i.e., total) and myofibrillary proteins remained unaltered in both WKY rats and SHR, as were cellular efficiencies. The RNA activity was significantly reduced in ethanol-treated SHR but not in WKY rats. In ethanol-treated SHR, cardiac creatine kinase (CK) and malate dehydrogenase (MDH) activities were increased, AMP levels were elevated, whilst ATP levels and the energy charge were reduced. In WKY rats, the only significant change related to increased aspartate aminotransferase activities in response to alcohol feeding. Although there were only subtle differences between the response of the normotensive and hypertensive rats due to ethanol dosage, the reduced ATP levels and increased CK and MDH activities in SHR may reflect a greater susceptibility to ischaemic damage. Reduced contractile protein content, particularly myosin heavy chain, may contribute to contractile defects, a common feature of subclinical and clinical alcoholic cardiomyopathy. 相似文献
60.