Agitated bacterial tank bioleaching reactors are currently sparged with air to satisfy both oxygen and CO(2) requirements of microbial cells. Under high-sulphide loading conditions, as is the case with high-grade metal sulphide concentrates, the microbial and chemical demand for oxygen is significantly increased during the bioleaching process. Sparging with enriched oxygen gas may offer an alte...

Rabbit lens epithelial cells display a similar "cobblestone" morphology and produce the same complement of sulphated macromolecules (also see Heathcote, J.G., and R.W. Orkin, 1984, J. Cell Biol., 99:852-860) whether grown on plastic or glass, dried films of gelatin or type IV collagen with laminin, or on gels of type I collagen. There was no evidence of basement membrane formation by these cell...

1. A trypsin inhibitor from the tick Boophilus microplus was purified by ion-exchange chromatography and gel filtration. 2. It is pure by the criteria of constant specific activity on gel filtration and by electrophoresis on polyacrylamide gels containing sodium dodecyl sulphate. 3. The protein undergoes reversible polymerization, dissociating at low pH. 4. The apparent molecular weight measure...

measured by CO-reduced difference spectroscopy (Omura & Sato, 1964) was retained on this column. The concentrated CM-cellulose eluate was dialyzed to pH7.4, and then applied to a DEAE-Sephadex or QAE [diethyl-(2-hydroxypropyl)aminoethyl]-Sephadex column. Peak I eluted from the DEAE-Sephadex exhibited UTP-glucuronyltransferase activity. UDP-glucuronyltransferase activity towards various substrat...

The 30S ribosomal subunit of E. coli was treated with the bifunctional reagent bis-(methyl)suberimidate. Crosslinked ribosomal proteins were identified as bands with increased molecular weight after electrophoresis in polyacrylamide gels containing sodium dodecyl sulphate. The pattern of crosslinked products was altered when unfolded subunits were used. Free ribosomal protein was not crosslinke...

Abstract Magnetic Fe 3 O 4 nanoparticles (NPs) were successfully synthesized via co-precipitation method using ferric chloride and ferrous sulphate as the starting materials. The shape size of NPs controlled by different types additive including ammonium hydroxide sodium hydroxide. results revealed that adding hydroxide, particles attained a spherical with uniform size. On other hand, turned fr...