Surface properties of poly(N-monoalkylmaleamic acid-alt-styrene) sodium salts: effect of the molecular weight and the side chain length

The surface properties of poly(N-monoalkylmaleamic acid-alt-styrene) sodium salts are studied as a function of the molecular weight and the size of the linear alkyl lateral chain of the polyelectrolyte. The experimental results are well described by the Gibbs-Szyszkowski treatment. Both the surface tension behavior and the standard free energy of adsorption depend on the polyelectrolyte side chain and on the average molecular weight, M(w). An M(w)-dependent contribution to the free energy of adsorption ranging from -1.21 to -1.05 kJ for mole of methylene groups is found. The area covered by monomer units increases with M(w) and the sizes of side chains are similar to those reported in small-molecule systems. The nature of the functional group amide in the side chain has practically no effect on the surface properties as compared with the ester group in this kind of polyelectrolytes.     

Autoradiography of mineral ions in green leaves and flowers,absorbed with and without synthetic fulvic acids

The disproportionation of pentavalent plutonium is traditionally represented by two inconsistent equations. The inconsistency puts the widely-accepted, fourth-power hydrogen-ion dependence of the reaction into question. The balanced reaction equation suggests that both the stoichiometry and the acid-dependence of Pu(V) disproportionation depend on the pH of the plutonium solution.Los Alamos National Laboratory is operated for the U.S. Department of Energy by the University of California under Contract No. W-7405-ENG-36.     

Copper-catalyzed anti-stereocontrolled ring-opening of azabicyclic alkenes with Grignard reagents

[Reaction: see text] The anti-stereocontrolled alkylative ring-opening reaction of azabicyclic alkenes is reported. N-(2-Pyridyl)sulfonyl azabenzonorbornadiene reacts with Grignard reagents in the presence of catalytic amounts of CuCN to afford, in good yields and excellent anti selectivity, the corresponding dihydronaphthalene-1-amines.     

Design,synthesis, molecular docking and in vitro evaluation of benzothiazole derivatives as 11β-hydroxysteroid dehydrogenase type 1 inhibitors

Molecular Diversity - 11-Beta hydroxysteroid dehydrogenase type 1 (11β-HSD1) regulates cortisol levels mainly in adipose, hepatic and brain tissues. There is a relationship between the high...