For more than a century, urea has been commonly used as an agent for denaturing proteins. However, the mechanism behind its denaturing power is still not well understood. Here we show by molecular dynamics simulations that a 7 M aqueous urea solution unfolds a chain of purely hydrophobic groups which otherwise adopts a compact structure in pure water. The unfolding process arises due to a weake...

Preparation of Phenolic nanocomposites with the help of solvent casting technique was carried out by dispersing the chitin nano particles in water soluble phenol formaldehyde (PF). The nanocomposites were prepared by using water suspended chitin whisker as the reinforced phase and water soluble phenol formaldehyde (PF) as matrix. In the present work, crab shell originated chitin whisker was pro...

Acetylation of wood imparts moisture durability, decay resistance, and dimensional stability to wood; however, making durable adhesive bonds with acetylated wood can be more difficult than with unmodified wood. The usual explanation is that the acetylated surface has fewer hydroxyl groups, resulting in a harder-to-wet surface and in fewer hydrogen bonds between wood and adhesive. This concept w...

Here, we introduce a highly porous functional mesoscopically silica-polymer composite based on silica monolith-conjugated thiourea/formaldehyde copolymer. The developed nanostructure enables selective and fast removal of the radioactive pollutants strontium (Sr[II]) cesium (Cs[I]) ions from contaminated seawater. silica/polymer was synthesized by introducing solution into tetramethoxy orthosili...

.~Q).~"('a-.L,t.:.:z. ~ 7, ~,. ~:';, ~,. ~ :';0.:z.1) 7~.8'..Q)_t' C-13 NMR I.: J:? -rff~~, ~"} ~ :,; t.:z. ~ 7~r~ of" v :,;.8'~~ ~ of" v ~ .x.-1" IvM8'~ J: ? -r ~.8'T.o .: t~r~~"('! o~~~~ ~~t'~~~. .:z. ~ Y"t ~"} ~ :,;..~~ of" v ~M~~~.I.:!.o y ?,j-lvl~, ~8L, -r""('8, ~.'8'.Q)~ 'f-v ~.~Q)..y?,j"" t~8L, -rmJJ.T.o': t ~rU~n~. ~~ of"v~.x.-T"".~I.:! .o~.y?,j-lvl~, .:z. ~ 7W.t ~"} ~ ~.II"t'O.9 ppm 8t...

Three types of adhesives, urea-formaldehyde (UF) resin, phenol-formaldehyde (PF) resin, and polymeric methylene bis(phenyl isocyanate) (pMDI), were used for investigating the effect of pressing variables on volatile organic compound (VOC) emissions. The variables examined included press temperature and time, mat moisture content and resin content, and board density. The VOCs emitted during part...

this research was conducted to investigate the effect of acetylation and type of resin on fire resistance of one and three layered populus particleboard. populus particles were acetylated at three levels of acetyl content (wpg of 0, 8.39% and 17.27%). in manufacturing of one and three layered boards with acetylated particles in all thickness or surface of the boards two type of resin, urea form...

paper only the treatments receiving commercial urea prills Using maize as the indicator crop for recently tilled soils over seven successive seasons, urea prills coated with 0,5% polymer gave the greatest grain yield increases over commercial urea in seasons of below average rainfall (3,3 tonsha versus 1,6 tonsha in 1989-90). The ratios of grain to stover were also higher. In wet years, no diff...