Polycondensation catalyzed by polyvinyl pyrrolidone-supported metal complexes

Polyvinyl pyrrolidone (PVP) in cataract surgery.

Early reformation of the anterior chamber after intraocular surgery is of paramount importance, its absence or delay leading to peripheral anterior synechiae and aphakic glaucoma (Troncoso, 1933; Kronfeld and Grossman, 1941; McLean, I94I; Meyer and Sternberg, 1950). Selinger (1937) injected air after cataract operations to restore the normal curvature of the cornea. He concluded that air preven...

Enantioselective cyclizations of silyloxyenynes catalyzed by cationic metal phosphine complexes.

The discovery of complementary methods for enantioselective transition metal-catalyzed cyclization with silyloxyenynes has been accomplished using chiral phosphine ligands. Under palladium catalysis, 1,6-silyloxyenynes bearing a terminal alkyne led to the desired five-membered ring with high enantioselectivities (up to 91% ee). As for reactions under cationic gold catalysis, 1,6- and 1,5-silylo...

Nickel (0) Catalyzed Kumada Chain Transfer Polycondensation

Corrosion Inhibition of Mild Steel in 1 M H2SO4 by Polyvinyl Pyrrolidone and Synergistic Iodide Additives

The corrosion inhibition of mild steel in 1M H2SO4 by polyvinyl pyrrolidone (PVP) and the synergistic effect of iodide ions were investigated using weight loss and hydrogen evolution methods in the temperature range of 30 – 60 o C. The corrosion rates of mild steel decreased with the increasing concentration of PVP, while the inhibition efficiency (%I) increased. The inhibition efficiency of PV...

Properties of polyvinyl pyrrolidone/beta-chitosan hydrogel membranes and their biocompatibility evaluation by haemorheological method.

The semi-IPN hydrogel membranes of polyvinyl pyrrolidone (PVP) and beta-chitosan were synthesized by crosslinking beta-chitosan with glutaraldehyde. Hydrogel membranes were characterized by spectroscopic, swelling, thermal and mechanical properties. The in vitro biocompatibility of hydrogel membranes was studied by haemorheological method. These hydrogels have water contents in the range of 60-...