Renin was purified from 47 kg of hog kidney to produce enough enzyme for enzymatic and physicochemical characterization. The procedure included extraction at pH 3.5 in the presence of protease inhibitors, two ammonium sulfate precipitations, ion exchange chromatography on Sepharose-hexamethylenediamino-pepstatin gel, gel filtration, and isoelectric focusing. Renin, 2.3 mg, with a specific activ...

gelled propellants are improved propellants that can be considered as the final extension of liquid propellants. high specific impulse, good density and safety better than that of both solid and liquid propellants are advantages of the gel propellants. they are made by addition a suitable gellant to liquid propellants. in this research, nano al particles have been used in udmh gel fuel. the gel...

We investigate the behavior of the shear viscosity eta(p) and the mass-dependent diffusion coefficient D(m,p) in the context of a simple model that, as the cross link density p is increased, undergoes a continuous transition from a fluid to a gel. The shear viscosity diverges at the gel point according to eta(p) approximately (p(c)-p)(-s) with s approximately 0.65. The diffusion constant shows ...

We investigate volume phase transition in gels immersed in mixture solvents, on the basis of a three-component Flory-Rehner theory. When the selectivity of the minority solvent component to the polymer network is strong, the gel tends to shrink with an increasing concentration of the additive, regardless of whether it is good or poor. This behavior originates from the difference of the additive...

A new species of Pseudomonas was isolated that produced copious amounts of an exocellular heteropolysaccharide (PS-60) after incubation for 3 days at 30 degrees C in media containing 3% glucose as a carbon source. The polysaccharide was composed of approximately 46% glucose and 30% rhamnose and, in addition, contained 21% uronic acid and 3% O-acetyl. Upon deacetylation by a mild alkaline treatm...

Drilling cost optimization has always been an important issue in the petroleum industry. In order to save costs and create new markets for local materials, Ofo (D. micocarpum) and food gum (C. populnea) powders were evaluated in this study at high temperature as alternative to imported chemical additives in water based drilling fluid. The base mud composed of alkali beneficiated local clay, ach...