a fi zr-based catalyst of bis[n-(3,5-dicumylsalicylidene)-2′,6′­diisopropylanilinato]zirconium(iv) dichloride was prepared and used for polymerization of ethylene. the effects of reaction conditions on the polymerization were examined in detail. the increase in ethylene pressure and rise in polymerization temperature up to 35 oc were favorable for catalyst/mao to raise the catalytic activity as...

chitosan/polyethersulfone (cs/pes) composite membrane was prepared from casting chitosan solution on polyethersulfone substrate membrane. the substrate membrane was prepared by phase inversion technique using polyethersulfone (pes) and dimethylacetamide (dmac) as solvent with and without the addition of polyvinylpyrrolidone (pvp) as pore-forming agent. the effects of the composition of the c...

Numerous determinations of the amino acid composition of various commercial preparations of the protamine, salmine, have been made (l-6). From several of these determinations (1, 2,4, 6) minimal molecular weights ranging from 7000 to 10,000 have been calculated on the assumption that the preparations were homogeneous. Analyses of two commercial samples (Krishell’ and Sharp and Dohme*) in this l...

The molecular weights of the dcnsclr fraction of porcine plasma high density (1.1 lo 1.2 g per ml) lipoprotein and its protein subunits were estimated to determine the number of chains and to characterize the molecular species for further studies. These estimates are compared with those reported for human HDL3.’ Shore and Shore (1) deduced that human plasma HDL, was compoerd of three identical ...

We have developed a microfluidic system for polymerization of amino acid N-carboxyanhydride and compared the properties of the products with those obtained by batchwise system under various experimental conditions. It was found that the microreactor produced polymers with narrower molecular weight distribution compared with polymers obtained by the batchwise system. Also, the molecular mass of ...