1. An enzyme, “chondroitinase-ABC,” has been purified to apparent homogeneity from extracts of Proteus vulgaris, NCTC 4636, which was adapted on a medium containing chondroitin sulfate C. It has the following properties. (a) At pH 8, it degrades chondroitin sulfates A, B, and C at greater rates than chondroitin and hyaluronic acid. It does not attack keratosulfate, heparin, or heparitin sulfate...

Novel cyclic olefin polymers (COPs) derived from bulky cyclic olefins, tricyclodipentadiene (TCPD) and tricyclo[6.4.0.19,12]-tridec-10-ene (TTE), with high glass transition temperature (Tg), excellent thermal stability, and high transparency, have been synthesized by ring-opening metathesis polymerization (ROMP) and subsequent hydrogenation. ROMP of TCPD and TTE was carried out successfully wit...

The biosynthesis and characterization of medium chain length poly-3-hydroxyalkanoates (mcl-PHA) produced by Pseudomonas putida Bet001 isolated from palm oil mill effluent was studied. The biosynthesis of mcl-PHA in this newly isolated microorganism follows a growth-associated trend. Mcl-PHA accumulation ranging from 49.7 to 68.9% on cell dry weight (CDW) basis were observed when fatty acids ran...

A new procedure for the preparation of thick polymethacrylate films bonded in 25 μm i.d. fused-silica capillaries is developed. The etched silica surface is first modified with an unsaturated organosilane, which is later incorporated into the polymer film. The capillary is then filled with a monomer solution, and polymerization is initiated by incubation at elevated temperature. This thermoinit...

The cross-metathesis of polynorbornene and polyoctenamer in d-chloroform mediated by the 1(st) generation Grubbs' catalyst Cl2(PCy3)2Ru=CHPh is studied by monitoring the kinetics of carbene transformation and evolution of the dyad composition of polymer chains with in situ (1)H and ex situ (13)C NMR spectroscopy. The results are interpreted in terms of a simple kinetic two-stage model. At the f...

Due to the unique properties of C?F bonds, organofluorine compounds occupy a privileged space in pharmaceutical, agrochemical, and polymer industries. Carbofluorination reactions involve formation C?C bond, typically across ?-bond or another unsaturated functionality that is revealed upon situ activation. The design tailored substrates new catalyst systems has enabled carbofluorination chemistr...

Hyaluronic acid (HA)’ is a polysaccharide composed of equimolar amounts of n-glucuronic acid and N-acetylglucosamine. The basic repeating unit of the straight chain polymer is the disaccharide, N-acetylhyalobiuranic acid (3P-D-glucuronopyranosyl-N-acetylglucosamine (3)). The polysaccharide is hydrolyzed by enzymes from various sources such as mammalian testis, bacteria, snake venom, and others....

determination of volume change of unsaturated soils during loading and suction change is one of the most important difficulties in testing unsaturated specimens. it is revealed from literature review that various attempts have been made to invent an apparatus that can be used in testing on unsaturated soil specimens, simply and accurately. in this research, details of design and manufacture of ...

Abstract An experiment was conducted to compare the unsaturated hydraulic conductivity (K) calculated by Jackson equation and van Genuchten for soils different in gypsum content treated with some soil conditioners. Two were used, gypsiferous (410 gm kg-1gypsium) clayey (435 kg-1 clay), mixed three levels 0, 50, 100%. The peat moss 0 and1%, polymer,0,1.and 2% without addition. Then, packed into ...