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981.
The level structure of178Hf is interpreted on the basis of the population of the states following178Hf (d, d′),177Hf (d, p) and179Hf (d, t) reactions. Evidence for quadrupole and octupole vibrational bands and unmixed and intermixed two-quasiparticle configurations
is presented. 相似文献
982.
T. Datta S. P. Dange S. M. Sahakundu S. Prakash M. V. Ramaniah 《Zeitschrift für Physik A Hadrons and Nuclei》1988,330(1):103-109
In the present work rms angular momenta have been deduced for the fission fragments corresponding to131Tem,g and133Tem,g in232Th(α 40 MeV,f) and238U(α 40 MeV,f) systems from the radiochemically determined independent isomeric yield ratios and statistical model based analysis. For131Te and133Te the rms angular momenta deduced are 5.9±1.0 and 7.9±1.2 ? respectively in232Th(α 40 MeV,f) and 7.2±0.6 and 8.0±0.8 ? respectively in238U(α 40 MeV,f). Comparison of the present data with the literature data for these fragments in the same compound nuclei236U* and242Pu* at lower excitation energies shows increase in the fragment angular momentum with increasing excitation energy and angular momenta of the fissioning nuclei. Fragment angular momentum deduced theoretically for asymmetric and deformed fragments on the basis of thermal equilibration of the collective rotational degrees e.g., rigid rotation, wriggling, tilting, bending and twisting modes considering the effect of multichance fission, are in good agreement with the experimental observations. 相似文献
983.
The strain field due to body centered substitutional transition metal impurities in Ni and Pd metals are investigated. The
calculations are carried out in the discrete lattice model of the metal using Kanzaki lattice static method. The effective
ion-ion interaction potential due to Wills and Harrison is used to evaluate dynamical matrix and the impurity-induced forces.
The results for atomic displacements due to 3d, 4d and 5d impurities (Fe, Co, Cu, Nb, Mo, Pd, Pt and Au) in Ni and (Fe, Co,
Cu, Ni, Nb, Mo, Pt and Au) impurities in Pd are given up to 25 NN’s of impurity and these are compared with the available
experimental data. The maximum displacements of 4.6% and 3.8% of 1NN distance are found for NiNb and PdNb alloys respectively,
while the minimum displacements of 0.63% and 0.23% of 1NN distance are found for NiFe and PdFe alloys respectively. Except
for Cu, the atomic displacements are found to be proportional to the core radii and d state radius. The relaxation energies
for 3d impurities are found less than those for 4d and 5d impurities in Ni and Pd metals. Therefore, 3d impurities may easily
be solvable in these metals. 相似文献
984.
Some modifications have been suggested to the nodal slide and microscope method to suit the focal length measurement of large focal length lenses. In this procedure, the experimental set-up has to be accommodated on the two usual optical benches in line, and the position of the nodal point of the lens under test is easily located by introducing an extra lens of comparatively shorter focal length between the test lens and microscope. The results of the measurement of ‘f’ for a few lenses, and the experimental parameters, are presented. 相似文献
985.
The effect of finite Larmor radius, magnetic field, rotation and variable gravitational field on thermal instability of fluid
layer in porous medium is investigated. It is found that the principle of exchange of stability is valid in the absence of
magnetic field and rotation. The system is stable/unstable depending upon certain conditions in the presence of rotation,
magnetic field and medium permeability. The system is stable in presence of finite Larmor radius.
The above work has been carried out under research project financed by University Grants Commission New Delhi (India) and
the authors are grateful to University Grants Commission for their financial support. 相似文献
986.
Sanju KS Neelakandan PP Ramaiah D 《Chemical communications (Cambridge, England)》2011,47(4):1288-1290
We observed FRET between an excimer of a partially intercalated cyclophane and ethidium bromide, a classical intercalator in presence of DNA and by fine-tuning the molar concentrations of these three components, we could generate white light emission in the aqueous and non-aqueous media. 相似文献
987.
988.
989.
The gas phase structure, stability, spectra, and proton transfer properties of monoprotic carborane acid-water clusters [CB(11)F(m)H(11-m)(OH(2))(1)]-(H(2)O)(n) (where m = 0, 5, and 10; n = 1-6) have been calculated using density functional theory (DFT) with the Becke's three-parameter hybrid exchange functional and Lee-Yang-Parr correlation functional (B3LYP) using 6-31+G* basis set. Results reveal that Eigen cation defects are found in CBW(n) (where n = 2-6) clusters and these clusters are significantly more stable than the non-Eigen geometry. In addition to the conventional hydrogen bond (H-bond) the role of dihydrogen bond (DHB) and halogen bond (XB) in the stabilization of these clusters can be observed from the molecular graphs derived from the atoms in molecules (AIM) analysis. Spectral information shows the features of Eigen cation and proton oscillation involved in the proton transfer process. The dissociation of proton from the perfluoro derivatives with two water molecules is more favorable when compared to the other derivatives. 相似文献
990.
Beier P Opekar S Zibinsky M Bychinskaya I Prakash GK 《Organic & biomolecular chemistry》2011,9(11):4035-4038
A new route to α-alkyl-α-fluoromethylenebisphosphonates, 2 has been developed starting from commercially available tetraethyl fluoromethylenebisphosphonate (1), and alkyl halides using either caesium carbonate in DMF or sodium dimsyl. De-esterification of 2 provided biologically important α-alkyl-α-fluoromethylenebisphosphonic acid, 3, while alkoxide-induced carbon-phosphorus bond cleavage of 2 gave α-fluorophosphonates, 4, which are useful synthons in organic synthesis. 相似文献