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991.
H. Blok H.P. Blok J.F.A. van Hienen G. van der Steenhoven C.W. de Jager H. de Vries A. Saha K.K. Seth 《Physics letters. [Part B]》1984,149(6):441-446
The excitation of 0+ states in 58Ni and 26Mg has been investigated by inelastic electron scattering. Shell model calculations in a 1&?;ω model space are not able to reproduce the data, which clearly show contributions from 2&?;ω, i.e. giant monopole resonance-like, excitations. 相似文献
992.
Sisir K. Saha Ajit K. Chaudhuri 《Journal of polymer science. Part A, Polymer chemistry》1971,9(6):1505-1516
The polymerization of acrylonitrile was studied in aqueous solution with ceric ammonium sulfate in the presence of triethylamine as initiator at 30, 40, and 50°C. The rate of polymerization was found to be linear with the concentration of the amine and independent of ceric ion concentration. A reaction scheme involving initial complex formation between ceric ion and the amine and subsequent disproportionation of the conplex to produce free radicals is proposed for the initiation reaction. The termination step is postulated as involving oxidation of the polymer chains by ceric ions. The results have been explained in the light of the proposed reaction scheme. 相似文献
993.
R. K. Garg S. D. Chauhan S. L. Gupta N. K. Saha 《Zeitschrift für Physik A Hadrons and Nuclei》1971,244(4):312-320
The half-lives of the 86.6 keV level in233Pa and the 59.6 keV level in237Np have been measured. A silicon surface barrier alpha detector and a NaI(Tl) gammadetector were used. The decay time spectrum of alpha-gamma coincidences obtained from a start-stop type of time-to-pulse height converter was recorded on a 2048-channel analyser. Analysis of the data gave the following half-life values: $$\begin{gathered} T_{\frac{1}{2}} :^{233} Pa (86.6 keV level) = (37.4 \pm 0.4) ns \hfill \\ T_{\frac{1}{2}} :^{237} Np (59.6 keV level) = (66.7 \pm 0.7) ns \hfill \\ \end{gathered}$$ . Using the experimental levelT 1/2's, partial gamma-ray half-lives have been calculated for the 86.6- and the 29.6-keV transitions (from the 86.6 keV level) in233Pa and the 59.6- and the 26.36-keV transitions (from the 59.6 keV level) in237Np. The results are compared with the single particle and the Nilsson estimates. 相似文献
994.
A Uniqueness Problem in Valued function Fields of Conics 总被引:1,自引:0,他引:1
Let v0 be a valuation of a field K0 with value group G0. LetK be a function field of a conic over K0, and let v be an extensionof v0 to K with value group G such that G/G0 is not a torsiongroup. Suppose that either (K0, v0) is henselian or v0 is ofrank 1, the algebraic closure of K0 in K is a purely inseparableextension of K0, and G0 is a cofinal subset of G. In this paper,it is proved that there exists an explicitly constructible elementt in K, with v(t) non-torsion modulo G0 such that the valuationof K0(t), obtained by restricting v, has a unique extensionto K. This generalizes the result proved by Khanduja in theparticular case, when K is a simple transcendental extensionof K0 (compare [4]). The above result is an analogue of a resultof Polzin proved for residually transcendental extensions [8]. 相似文献
995.
B. Bhattacharyya A. Bhadra A. Mukherjee G. Saha S. Sanyal S. Sarkar B. Ghosh N. Chaudhuri 《Il Nuovo Cimento C》1995,18(3):325-334
Summary A detailed analysis of Extensive Air Showers in the size range 104–106 particles detected near sea level has yielded a new distribution function for the radial distribution of EAS electrons. The
goodness-of-fit criteria applied to the present and already existing similar distribution functions confirm that the present
function is appropriate in EAS at radial distances beyond 20 m from the shower axis. 相似文献
996.
The method of Das developed recently to analyse elastic scattering of electrons by atoms has been extended in the present
paper to inelastic scatterings. The method has been applied for the computation of 2S-excitation, cross-sections at two typical intermediate energiesviz. 54.4 eV and 100 eV energies. Some of the results are compared with available experimental results and are found to be in
satisfactory agreement with these. 相似文献
997.
998.
The recoil properties of ten fission products with masses ranging from 72 to 136 formed in the fission of 238U with protons of energies 25–85 MeV have been determined radiochemically by the integral-range method. From the recoil properties of the products and the Monte Carlo cascade calculations the average kinetic energy, cascade deposition energy, and anisotropy parameter for each fission product has been calculated. The kinetic energy and the excitation energy of the primary fragments leading to the observed fission product, and the total kinetic energy and the total excitation energy of the primary fragment pair have also been calculated.
The results indicate that up to a bombarding energy of 40 MeV fission takes place predominantly by the compound nucleus mechanism, with an increasing contribution of the direct interaction mechanism as the bombarding energy increases. The kinetic energy deficit was found to decrease with increasing bombarding energy. The fission products formed from the symmetric mode of fission have a larger separation distance between the charge centres of their respective primary fragments than those for the asymmetric mode of fission. 相似文献
999.
Room temperature, light promoted trimerization of a monomeric complex [Cu(HL)(L)](NO(3)).H(2)O (HL =N,N-dimethyl-N[prime or minute]-propylsalicylideneimine) dissolved in CH(2)Cl(2), was observed with the concomitant generation of new ligand moiety (ClCH(2)L). 相似文献
1000.
du Rietz R Ekman J Rudolph D Fahlander C Dewald A Möller O Saha B Axiotis M Bentley MA Chandler C de Angelis G Della Vedova F Gadea A Hammond G Lenzi SM Mărginean N Napoli DR Nespolo M Rusu C Tonev D 《Physical review letters》2004,93(22):222501
Following the heavy-ion fusion-evaporation reaction 32S+24Mg at 95 MeV beam energy the lifetimes of analogue states in the T(z)=+/-1/2 A=51 mirror nuclei 51Fe and 51Mn have been measured using the Cologne plunger device coupled to the GASP gamma-ray spectrometer. The deduced B(E2;27/2(-)-->23/2(-)) values afford a unique opportunity to probe isoscalar and isovector polarization charges and to derive effective proton and neutron charges, epsilon(p) and epsilon(n), in the fp shell. A comparison between the experimental results and several different large-scale shell-model calculations yields epsilon(p) approximately 1.15e and epsilon(n) approximately 0.80e. 相似文献