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41.
Franck–Condon factors are presented for the normal and stable isotope-labelled N2, O2, NO and CO molecules for transitions to the observed ionized states by using the Rydberg–Klein–Rees (RKR ) potential energy curves of the various electronic states involved. It has been observed that for some transitions, the Franck–Condon factors based on the RKR potential energy curves differ appreciably from those based on the Morse potential function. The effect of isotopic substitution on the transition probabilities is also quite significant in a number of cases.  相似文献   
42.
A new dinuclear ligand L, ethylene[OO-bis-salicylidene--diketone] bearing two symmetrical coordination sites was synthesized by the condensation of salicylaldehyde and acetylacetone, L, with 1,2-dibromoethane under reflux. The ligand L in a 1:1 ratio was treated with CuCl2 and NiCl2 to yield the complexes, tetrachloro bis[OO-bis- salicylidene--diketone copper(II)] and bis[OO-bis-salicylidene--diketone nickel(II)] chloride. The complexes were subsequently characterized by spectroscopic techniques, elemental analysis, i.r., 1H-n.m.r., 13C-n.m.r., u.v.–vis., e.p.r. spectroscopy, and conductance measurements. The conductance measurements in DMF reveal that the CuII complex is covalent while the NiII complex is ionic and the spectral data support the CuII complex to be distorted octahedral whereas the NiII complex has square-planar geometry. The dioxygen binding was studied spectrophotometrically by the oxidation of tetrachloro bis[OO-bis-salicylidene--diketone copper(II)] with pyrocatechol in the presence of oxygen. The kinetic experiments were performed with the copper complex in DMF by monitoring the increase in absorbance over time at pH 8.0 in the presence of pyrocatechol at 25 °C. The kinetic parameters Vmax and KM were determined on the Michaelis–Menten Approach. Redox behavior of the dinuclear copper(II) complex was investigated by cyclic voltammetry in the presence of O2 with the pyrocatechol (substrate) and also without the substrate. The large difference in potentials E0 is indicative of reversible oxygen binding of the complex and distinct catalytic activity.  相似文献   
43.
Summary Benzoylacetic acid (1 mol) interacts with ethylenediamine or with propanediamine (2 mol) to yield new N4 macrocycles 1,5,8,12-tetraazacyclotetradeca-2,4,9,11-tetraphenyl-3, 10-dicarboxylic-4,11-diacetic acid- 1,8-diene (L1) and 1,5,9,13-tetraazacyclohexadeca-2,4,10,12-tetraphenyl-3, 11-dicarboxylic-4,12-diacetic acid-1,9-diene (L2), respectively. These macrocycles have been successfully complexed with CrIII, FeIII, MnII, CoII, NiII, CuII and ZnII. The complexes of the divalent metal ions are non-electrolytes, while those of FeIII and CrIII are 1:1 electrolytes in DMSO. On the basis of ligand field spectra and magnetic moments an octahedral geometry has been proposed for all the complexes.  相似文献   
44.
We employ Kato's theorem to prove that the electron interaction potential of Kohn–Sham density functional theory is finite at the nucleus of spherically symmetric and sphericalized atoms and ions. Therefore, this finiteness is a direct consequence of the electron–nucleus cusp condition for the density. © 2000 John Wiley & Sons, Inc. Int J Quant Chem 79: 205–208, 2000  相似文献   
45.
Foreword     
V. C. Sahni 《Pramana》2008,71(4):611-613
  相似文献   
46.
We show that no multiprocessor system that contains at least one processor with memory size smaller than at least two other processors can be scheduled nearly on-line to minimize the finish time. An efficient nearly on-line algorithm to minimize Cmax is developed for multiprocessor systems that do not satisfy the preceding requirement.  相似文献   
47.
The applicability of variational principles for single-particle expectation values to the inhomogeneous electron gas at surfaces is demonstrated. Jellium metal surface densities, correct to second order, are determined by application of the formalism to the operator W=iδ(xi?x). The surface dipole barrier thus obtained is shown to lead to essentially exact results over a substantial range of the variational parameter employed. The procedure for inclusion of the discrete ionic lattice is also indicated.  相似文献   
48.
The irreducible multiplier representations (ray representation) for the pointsΓ and A of the Brillouin zone of the space group D 6h 4 are constructed using the method given in the previous paper.
Zusammenfassung Die irreduziblen Multiplikatordarstellungen (Strahldarstellungen) für die PunkteΓ und A der Brillouinzone der Raumgruppe D 6h 4 werden mit der Methode der vorangehenden Arbeit konstruiert.

Résumé Les représentations multiplicatrices irréductibles pour les pointsΓ et A de la zone Brillouin qui appertiennent au groupe d’espace D 6h 4 sont contruites en utilisant la méthode décrite dans un article précédent.
  相似文献   
49.
50.
The aim of the present study was to design and develop topical submicron size gel formulation of linseed oil with enhanced permeation through the skin for the management of psoriasis. Linseed oil contains significant amount of α-linolenic acid (ALA) an omega-3 fatty acid, which is responsible for its pharmacological actions. In order to enhance permeation through skin, microemulsion based gel formulation was prepared and characterized. Microemulsions were prepared by aqueous phase titration method, using linseed oil, Unitop 100, PEG 400, and distilled water as the oil phase, surfactant, cosurfactant and aqueous phase, respectively. Selected formulations were subjected to physical stability studies and consequently in vitro skin permeation studies. Surface morphology studies of optimized formulation were done by transmission electron microscopy (TEM). The droplet size of microemulsions ranged from 70 to 500 nm with average particle size 186 nm. The optimized microemulsion was converted into hydrogel using carbopol 971 which had a viscosity of 498 ± 0.04 cps. During in vitro permeation study the flux of microemulsion formulation and gel was found to be 19.05 and 10.2 µg/cm2/hr, respectively, which indicated better penetration of linseed oil through the skin. These result indicated that the developed ME formulation may be a good approach for topical therapy for the management of psoriasis.  相似文献   
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