objective(s): three-dimensional structures such as nanofibrous scaffolds are being used in biomedical engineering as well as provide a site for cells to attach and proliferate leading to tissue formation. in the present study, poly(vinyl pyrrolidone) (pvp)/ poly(vinyl alcohol)(pva) hybrid nanofibrous scaffold was synthesized by electrospinning. materials and methods: the effect of adding nano h...

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Multiple studies have explored using cage silsesquioxanes (SQs) as backbone elements in hybrid polymers motivated by their well-defined structures and physical mechanical properties. As part of this general exploration, we report unexpected photophysical properties copolymers derived from divinyl double decker (DD) SQs, [vinyl(Me)Si(O0.5)2][PhSiO1.5]8[(O0.5)2Si(Me)vinyl] (vinylDDvinyl). These e...

A 48-h treatment with vinyl acetate (0.05-1 mM) induced a drastic increase in sister chromatid exchanges (SCEs) and (in first division cells) structural chromosome aberrations in cultured human lymphocytes. The effects were more pronounced in cultures of isolated lymphocytes than in whole-blood cultures. A distinct dose-dependent induction of SCEs similarly occurred in Chinese hamster ovary cel...

polyvinyl ester green composites were synthesized with walnut shell powder (wsp) by in-situ polymerization technique. the green composites have been evaluated for mechanical properties such as tensile strength, tensile modulus and hardness. sliding wear loss, specific wear rate and coefficient of friction were investigated by using computerized pin-on–disc machine at normal applied loads of 20,...

Graft polymerizations of vinyl acetate onto granular corn starch were initiated by cobalt-60 irradiation of starch-monomer-water mixtures. and ungrafted poly(vinyl acetate) was separated from the graft copolymer by benzene extraction. Conversions of monomer to polymer were quantitative at a radiation dose of 1.0 IvIrad. However, over half of the polymer was present as ungrafted poly(vinyl aceta...

In this study, the emulsion homopolymerization system containing vinyl acetate, potassium persulfate, a new cationic polymeric surfactant and water was studied by the applying semi-continuous emulsion polymerization process. The effects of new polymeric emulsifier on the physicochemical properties of obtained vinyl acetate latexes were investigated depending on vinyl acetate percentage in the p...

The palladium-catalyzed conversion of aryl and vinyl triflates to aryl and vinyl halides (bromides and chlorides) has been developed using dialkylbiaryl phosphine ligands. A variety of aryl, heteroaryl, and vinyl halides can be prepared via this method in good to excellent yields.

extended abstract 1. introduction the translation of literary works in iran has always been subject to social and political conditions, intellectual tendencies, and dominant ideologies of the related historical period. hence, in each period the translators were inclined to translate specific literary works according to the beliefs and viewpoint of a distinguished political and social group. thu...