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981.
The coupled-channels formalism, which has been previously applied successfully to interpret the negative-parity resonances in4He, has now been extended to the positiveparity 2?ω resonances in this system. The 1p-1h approach has been modified to include coupling to the 2p-2h configurations, which also belong to 2?ω excitations, by using the effective operator formalism. The effect of the Pauli term in thes-wave channel is examined and is found to be important in reproducing the 0+,T=0 resonance energy and width. Resonances with spins up toJ π=3+ have been studied, and the agreement with available data is satisfactory. In particular, from the good fit to the asymmetry coefficientβ(E), one establishes the presence of a 2+,T=0 resonance around 35-MeV excitation in the system. 相似文献
982.
In recent work, we have shown that in the adiabatic limit (large amplitude, small momentum), time-dependent Hartree-Fock theory (TDHF) yields a well-defined theory of large-amplitude collective motion which provides an essentially unique construction for a collective hamiltonian. An alternative theory, put forward by Rowe and Basserman and by Marumori is, apparently, not restricted to small momenta. We describe a general framework for the study of collective motion in the semi-classical limit without limitation on the size of coordinates or momenta, which includes all previous methods as limiting cases. We find it convenient, as in the past, to consider two general systems: first, a system with n degrees of freedom and no special permutation symmetry, and, second, a system of fermions described in TDHF. For both systems the problem can be formulated as a search for a hamiltonian flow confined to a finite-dimensional hypersurface in a phase space, which itself may be finite- or infinite-dimensional. Though, in general, there are no exact solutions to this problem, we can formulate consistent approximation schemes corresponding to both the adiabatic and Rowe-Basserman, and Marumori limits. We also show how to extend the momentum expansion, which underlies the adiabatic approximation, to higher orders in the momentum. We thereby confirm the structure of the theory found in our previous work. 相似文献
983.
H. Wohanka G. Kungebiel M. Locke G. Klingebiel J. Suk K. Daďourek J. Tichý J. Zelenka J. Kraus L'. Hrivnák O. Taraba V. Petržílka J. Tichý J. Zelenka V. Zima J. Dočekal V. Vachala V. Hammerschmied V. Kroupa J. Hanzl F. Nykl F. Soška L. Sodomka L. Kyncl M. Jech 《Czechoslovak Journal of Physics》1966,16(5):456-462
984.
985.
A theory is developed by use of the correlation function approach for calculating both the Hv and Vv intensity of scattered light for a concentrated assembly of spherulities. The scattering becomes a function of the radial and tangential polarizabilities of the spherulite αr and αt, the polarizability αm of the medium, surrounding the spherulites, and the volume fraction ?s of spherulites. The “effective polarizability of the surroundings” αs, which appeared in previous theories, becomes function of these variables. The theory can explain, for example, why the Vv scattered intensity passes through a maximum during the course of crystallization. 相似文献
986.
Van Do Nguyen Duc Khue Pham Tien Thanh Kim Md. Shakilur Rahman Kyung-Sook Kim Guinyun Kim Hee-Seock Lee Moo-Hyun Cho In Soo Ko Won Namkung Tae-Ik Ro 《Journal of Radioanalytical and Nuclear Chemistry》2010,283(3):683-690
The isomeric yield ratios for the natFe(γ,xn1p)52m,gMn reactions have been measured by the activation and the γ-ray spectroscopic methods at 50-, 60-, 70-MeV, and 2.5-GeV bremsstrahlung energies. The high purity natural iron foils in disc shape were irradiated with uncollimated bremsstrahlung beams of the Pohang Accelerator Laboratory. The induced activities in the irradiated foils were measured by the high-resolution γ-ray spectrometry with a calibrated high-purity Germanium (HPGe) detector. In order to improve the accuracy of the experimental results the necessary corrections were made in the gamma activity measurements and data analysis. The obtained isomeric yield ratios for the natFe(γ,xn1p)52m,gMn reactions at 50-, 60-, 70-MeV, and 2.5-GeV bremsstrahlung energies are 0.27 ± 0.03, 0.33 ± 0.04, 0.34 ± 0.04, and 1.25 ± 0.15, respectively. The present results at 50-, 60-MeV, and 2.5-GeV bremsstrahlung energies are the first measurements. We found that the isomeric yield ratio of the natFe(γ,xn1p)52m,gMn reaction depends on the incident bremsstrahlung energy and the mass difference between the product and the target nucleus when we compared the present results with other experimental data at different energies. 相似文献
987.
We compute explicitly the oscillation constant for certain half-linear second-order differential equations involving periodic coefficients. If these periodic functions are constants, our results reduce to the well-known oscillation constants for half-linear Euler and Riemann–Weber differential equations. 相似文献
988.
G. Le Guillanton Q. T. Do D. Elothmani J. Simonet 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):375-376
Abstract The electrooxidation of sulfur in organic solvents leads to the formation of the cationic species S2+ Macroscale electrolyses are carried out with a sacrificial carbon-sulfur anode. S2+ can react either with aromatics to give monosulfides by electrophilic substitution, or with nucleophiles, thiols for example, to give trisulfides. 相似文献
989.
Nguyen Thi Hien Guinyun Kim Kwangsoo Kim Muhammad Nadeem Md. Shakilur Rahman Nguyen Van Do Pham Duc Khue Kim Tien Thanh Sung-Gyun Shin Moo-Hyun Cho 《Journal of Radioanalytical and Nuclear Chemistry》2017,311(3):1559-1564
We measured the isomeric yield ratios for the 110Pd(γ,n)109m,gPd reaction by the activation method with the bremsstrahlung endpoint energies of 50-, 55-, 60-, 65-, and 70-MeV generated from an electron linear accelerator of Pohang accelerator laboratory. The induced γ-activities of the irradiated palladium foils were measured by a coaxial high purity germanium detector coupled to a PC-based multi-channel analyzer. The necessary corrections were made to improve the accuracy of the γ-activity measurements. The present experimental results measured with bremsstrahlung endpoint energies of 50-, 55-, 60-, 65-, and 70-MeV are 0.108 ± 0.007; 0.118 ± 0.008; 0.118 ± 0.007; 0.120 ± 0.008; 0.119 ± 0.008, respectively. The obtained results are compared with those existing in literature. 相似文献
990.
Proteome characterization of human pancreatic cyst fluid from intraductal papillary mucinous neoplasm by liquid chromatography/tandem mass spectrometry
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