Liquid-phase hydrogenation of 1-hexene and phenylacetylene over multicomponent nickel skeleton catalysts

This paper presents the results of a study of the process of hydrogenation of 1-hexene in ethanol and phenylacetylene in a hexanewater suspension over multicomponent nickel skeleton catalysts It was demonstrated that the activity of multicomponent skeleton nickel catalysts is substantially dependent on the nature of the additives introduced into the bearing alloy. Introduction of Cu, Pb and Ta leads to an increase in activity (W=196-295cm3/min-gNi). The major mechanism of the effect of emulsion composition on the rate and selectivity of hydrogenation of phenylacetylene involves a change in the coefficient of distribution of substances between the solution and the surface of the skeleton nickel catalyst. It was also shown that the presence of water, which competes with unsaturated hydrocarbons during adsorption, adversely affects the process of purification from acetylenic hydrocarbons, as well as the stereo-regular polymerization of monomer. The research results of the kinetics and direction of the processes of hydrogenation of phenylacetylene suggest significant effect of the adsorption factor, including the ratio of free energies, concentrations and spatial orientation of the molecules of the mixture components, as well as the interaction of reacting substances and hydrogen with thecatalyst surface.

Stereoselective adsorption utilizing l-phenylalanine imprinting chiral ordered mesoporous silica

l-Phenylalanine imprinting chiral ordered mesoporous silica (l-Phe-COMS) was endowed with unique structural features, showing a high stereoselective adsorption factor of up to 3.24 for l-phenylalanine over d-phenylalanine.

Mass Transfer Mechanisms of ASP Flooding in Porous Media

Experiments on chromatography separation are taken for ASP flooding. Mass transfer equation is estabilished and mutiple adsorption factor is obtained. Mutiple adsorption factor is used to analyze the experiment results. The Mass transfer property of alkali, surfactant and polymer during single fooding and ASP flooding and the effect on interfacial tension of oil/solution are discussed. The results show the diffrence of hesteris degree of alkali, surfactant and polymer deduce the chromatography separation, lowing the active of ASP flooding. Accoding to interfacial tension, the efficent length of ASP slug is discussed.

Conceptualisation of Diagnostic Agents: From Empirical In Vivo Screening to Rational In Vitro Predictive Parameters

A new rational conceptualisation protocol in new isotopic diagnostic agents has been designed to avoid systematic empirical in vivo screening. This protocol is based on multiple regression analysis, in order to determine the pharmacokinetic model capable of explaining in the best possible way the in vivo behaviour of molecules injected into an organism. Nine technetium complexes (99mTc-L) were synthesised from aminothiol ligand vectors. These complexes were characterised in terms of their physical, chemical and biological in vitro properties, i.e. lipophilicity (P), free fraction unbound to plasmatic proteins (Fup), the fraction unbound to blood cells (FuCb), and membrane adsorption fraction (Fad), an original factor assessed in vitro. Thus, two pharmacokinetic models were tested. The first takes into account the parameters classically used in pharmacokinetics (P, Fup, FuCb), and the second, in parallel with the first, includes the membrane adsorption rate (polar/apolar/polar membrane model). According to the phenomenon of tissular distribution, the explanatory power of the second model, including the Fad, is radically greater than that of the classical model. The comparative adjusted coefficient of determination ([Formula: see text]2) of the model, including the Fad versus [Formula: see text]2 of the first model, are heart (91%/6%), liver (89%/47%), spleen (64%/44%), lung (78%/26%), kidney (70%/33%) and brain (73%/8%), respectively. In addition, as for the myocardium, the membrane adsorption factor seems to be the only predictive factor of the affinity between the myocardium and neutral or cationic molecules. This refutes the generally held view that only cationic molecules could have an affinity with the heart.