Relationships Between the Lipophilicity and Anticonvulsant Activity of N-Benzyl-2-azaspiro[4.4]nonane- and [4.5]decane-1,3-dione Derivatives

JPC – Journal of Planar Chromatography – Modern TLC - The lipophilicity of twenty-one N-benzyl-2-azaspiro[4.4]nonaneand [4.5]decane-1,3-dione derivatives, fifteen of which (1–15)...     

Molecular transient effects in K-band spectroscopy

The time dependence of microwave transient absorption and emission was measured forJ=2←1 of the OCS molecule under on- and off-resonant conditions by the technique of Stark switching. The results are analyzed with the theory of a coherent electromagnetic wave interacting with a two-level quantum system through the electric dipole interaction to obtain the pressure dependence of the relaxation timesT ₂ and in consequence the pressure broadening parameterC _w=26.7±0.9 (μs·mTorr)^?1 has been obtained.     

A Comparison of the Experimental and ab Initio Values of theO NMR Chemical Shifts in the Carbonyl Group

New experimental and theoretical results are presented for the NMR shielding of oxygen in the carbonyl group. The experimental values clearly demonstrate that the solvent effects are very significant. The new results for the chemical shifts are in better agreement than the previous literature data with the corresponding ab initio values calculated for isolated molecules.     

Invariance of selfinjective algebras of quasitilted type under stable equivalences

We prove that the class of finite dimensional selfinjective algebras over a field which admit Galois coverings by the repetitive algebras of the quasitilted algebras, with Galois groups generated by compositions of the Nakayama automorphisms with strictly positive automorphisms, is invariant under stable and derived equivalences. Dedicated to Claus Michael Ringel on the occasion of his sixtieth birthday     

Spectrophotometric determination of olanzapine by its oxidation with N-bromosuccinimide and cerium(IV)sulfate.

Three simple spectrophotometric methods have been described for the assay of olanzapine in its pure and pharmaceutical formulations. The direct method (A) is based on the drug oxidation with excess of N-bromosuccinimide in acidic medium and the two indirect methods (B and C) are based on the oxidation of the drug with excess of N-bromosuccinimide and cerium(IV)sulfate, followed by the reaction of the unconsumed oxidants with celestine blue. The calibration graphs were linear over the range 10 - 120 microg mL(-1) (method A), 0.5 - 6.0 microg mL(-1) (method B) and 0.6 - 3.0 microg mL(-1) (method C). After validation, the proposed methods were successfully applied to assay of olanzapine in its commercial tablets with mean percentage recoveries of 101.23 +/- 0.10, 96 +/- 0.10 and 94 +/- 0.04%. The mechanism of olanzapine oxidation with N-bromosuccinimide was also proposed.     

Field emission microscope investigation of oxide formation on Mo field emitters

The initial stages of oxide formation on Mo field emitter tips have been examined with the field emission microscopy and field electron spectroscopy. The oxide formed in situ on Mo tips by thermal treatment in pure oxygen atmosphere was found to be non-uniform with little evidence for coherent structure. The electron spectroscopy results are discussed in terms of the hypothesis that the emission process is a hot-electron emission.     

On the Glivenko-Cantelli problem in stochastic programming: Mixed-integer linear recourse

Expected recourse functions in linear two-stage stochastic programs with mixed-integer second stage are approximated by estimating the underlying probability distribution via empirical measures. Under mild conditions, almost sure uniform convergence of the empirical means to the original expected recourse function is established.