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121.
Adenine has been used as the template for the directed synthesis of 5-substituted imidazoles. A Novel intermediate involved in the cyclic operation has been characterised. 相似文献
122.
123.
Effects of the surface magnetic field (SMF), a laser and admolecule-phonon coupling on the dissociation of adsorbed diatomic molecules are studied theoretically. It is observed that the laser photon-dressing and the SMF-splitting of the molecular states give rise to a multiwell configuration, and the dissociation rate of a particular vibrational state in this configuration is altered as compared to the gas-phase laser-induced process. The presence of the phonon continuum also affects dissociation by dampening local transition probabilities at avoided crossings. Dissociation rates as function of laser power densities for a few specific systems are derived with a phonon-free situation and also with the presence of the phonon continuum, and the extent of phonon effects are analyzed. 相似文献
124.
A residual method of finite differencing the governing differential equation for the elliptic transport problem is presented. The new finite differencing technique is applied to (1) the one-dimensional transport problem and (2) the cavity flow problem for numerical illustrations. The results indicate the validity of the residual method of finite differencing. The usual method of term-by-term finite differencing, and considerations such as central differencing, hybrid differencing and upwind differencing are not needed in the present residual method. 相似文献
125.
Zirconium phosphate as ion exchanger suitable for column operation has been prepared by mixing hot metaphosphoric acid solution
with a solution of zirconium oxychloride when the white insoluble phosphate separated out which was dried and purified. The
ratio of zirconium: phosphate was found to be 1:2. Separation of parent-daughter systems like115Cd-115mIn,144Ce-144Pr and210Pb-210Bi were carried out with this exchanger. γ-ray spectrum of the separated115mIn and the β-decay curve of144Pr and210Bi showed that all the daughter activities are radiochemically pure. The separation process in each case takes less than half
an hour and the yield is quantitative. 相似文献
126.
127.
In this paper we develop a simple method for adapting the closed-shell many-body perturbation theory to an arbitrary point
group symmetry taking account of various classes of diagrams exactly to all orders. The method consists in deriving a linear
operator equation for the closed-shell wave-operatorW which is then symmetry-adapted to the pertinent point groupG. It is shown that the system of equations thus derived enables one to include orbital-diagonalh-h, p-p andh-p ladders to all orders in a perturbative framework. The way to generalise the method through inclusion of a larger classes
of diagrams to all orders is also indicated. Finally, the connection of the present mode of development with the non-perturbative
coupled-cluster formalisms is briefly indicated. 相似文献
128.
Bhattacharyya S Sil AN Mukherjee TK Mukherjee PK 《The Journal of chemical physics》2005,123(19):196102
Nonrelativistic energy of the (2p(2))(3)P(e) state of Be(2+) has been calculated using Ritz-variational method. The trial wave function is of Hylleraas type. The upper-bound energy E=-3.382 712 420 77 a.u. calculated by us is the lowest yet obtained. 相似文献
129.
Sinhamahapatra P. K. Bhattacharyya S. K. 《Journal of Thermal Analysis and Calorimetry》1975,8(1):45-56
Journal of Thermal Analysis and Calorimetry - Thermal characteristics of the molybdates of magnesium (MgMoO4 · 2H2O), manganese (MnMoO4 · 1.5H2O) and silver (Ag2MoO4) have been studied by... 相似文献
130.
The new molybdenum cyanonitrosyl complexes, R2[Mo(NO)(CN)5]·2H2O (R = Ph4P and Bu4N) and [Mo(NO)(CN)3(L-L)]·H2O [L-L = 相似文献