stability of the ;-; stacking interactions in the substituted-coronene||cyclooctatetraene complexes wasstudied using the computational quantum chemistry methods (where || denotes ;–; stackinginteraction, and substituted-coronene is coronene which substituted with four similar x groups; x =oh, sh, h, f, cn, and no). there are meaningful correlations between changes of geometricalparameters and t...

Ternary and quaternary metal chelates of some biologically important bivalent transition metal ions viz. Co(II), Ni(II), Cu(II) and Zn(II) formed with biologically significant ligands, viz. Asparagine (A) and Uracil (B) have been investigated. The relevant stability constants and complexation equilibria of quaternary metal chelates in solution at 30±1 oC and at constant ionic strength (I=0.1M N...

In the present work we investigate the stability constant of Adenosine drug with transition metal ions Fe, Co, Ni, Cu, Zn, and Cd using a pH metric titration technique in 20% (v/v) ethanol-water mixture at three different temperatures (25 °C, 35 °C, and 45 °C) and at an ionic strength of 0.1M NaClO4. The method of Calvin and Bjerrum as adopted by Irving and Rossotti has been employed to determi...

complexation reactions between methylthymol blue and fe , a l ,ga , 1n a nd ti ions have been studied in buffer aqueous solutions of ph 5.0 at 2s°c by a spectrophotometric technique. the conditional stepwise stability constants of the resulting 1:l and 1:2 (metal-to-ligand) complexes were determined from the absorbance-mole ratio data at three different wavelengths of the visible spectra. the o...

The [Pd(DEEN)Cl(2)] and [Pt(DEEN)Cl(2)] complexes were synthesized and characterized where DEEN = N,N-diethylethylenediamine. The stoichiometry and stability of the complexes formed between various biologically relevant ligands (amino acids, peptides, DNA constituents and dicarboxylic acids) and [Pd(DEEN)(H(2)O)(2)](2+) were investigated at 37 degrees C and 0.16 M ionic strength. The stability ...

equilibria of the reaction of molybdenum(vi) with l-aspartic acid (asp) and l- glutamic acid(glu) have been studied by spectrophotometric measurements in mixed solvent systems at an ionicstrength of 0.2 mol/dm3 sodium perchlorate, employed (15, 20, 25, 30± 0.1°c) at ph ranges of 3.2to 5.5 with a high ratio of ligand to metal. the stability constants of the complexes and theresulting free energy...

the complexation reaction between 1,13-bis(8-quinolyl)-1,4,7,10,13-pentaoxatridecane (kryptofix5) ligand with zn2+, ni2+, co2+, pb2+, mn2+ and cu2+ ions were studied conductometrically in different acetonitrile-nitromethane (an-nm) and acetonitrile-methanol (an-meoh) mixtures. the formation constants of the resulting 1:1 complexes were calculated from the computer fitting of the molar conductan...

We present a Static Universe in a generalized Brans-Dicke gravity theory, where the coupling “constant ” varies with time, as well as the scalar field. There is amplificatiom of gravitational waves in such Universe, at least when it is “young”. PACS 98.80-Hw

Ternary complexes of meloxicam (ME) (a poorly water soluble anti-inflammatory drug) with hydroxypropyl-beta-cyclodextrin (HPbetaCD) and either a hydrophilic polymer, namely, polyvinyl pyrrolidone (PVP) or a basic amino acid such as L-arginine, were prepared by the spray-drying technique. The solubilizing efficiency, physical properties and dissolution behaviour of each ternary system of ME-HPbe...