The biosynthesis of a yellow-green, fluorescent, water-soluble pigment by Pseudomonas jluorescens occurred only when the bacteria were iron-deficient and was not directly influenced by the nature of the organic carbon source. The pigment formed a very stable Fe3+ complex and was purified in this form. Pseudomonasfluorescens produced only one molecular species of fluorescent pigment; however, it...

Preliminary work by paper and thinlayer chromatography have indicated the existence of a number of similar antagonists with different specific activity. In the earlier stage of the purification, it was studied whether the minor components were real or artifacts. We found it convenient to use buffered resin chromatography according to the procedure of Moore et al.2) for the separation of detoxin...

Nanometer-sized titanium dioxide (TiO2) is an environmentally friendly optical semiconductor material. It has wide application value in many fields due to its excellent structural, optical, and chemical properties. The photocatalytic process of nano-TiO2 converts light energy into electrical or chemical energy under mild conditions. In recent years, the study and application of nano-TiO2 in the...

Freestanding graphene membranes are unique materials. The combination of atomically thin dimensions, remarkable mechanical robustness, and chemical stability make porous and non-porous graphene membranes attractive for water purification and various sensing applications. Nanopores in graphene and other 2D materials have been identified as promising devices for next-generation DNA sequencing bas...

Surfactant stabilized oil-in-water nanoemulsions pose a severe threat to both the environment and human health. Recent development of membrane filtration technology has enabled efficient oil removal from oil/water nanoemulsion, however, the concurrent removal of surfactant and oil remains unsolved because the existing filtration membranes still suffer from low surfactant removal rate and seriou...

Mycobactin S has been isolated from Mycobacterium smegmati8 and from Mycobacterium sp. Olitzky & Gershon, strain 2, and mycobactin H from M. thermore8i8tible; all three organisms were grown on synthetic media of low iron content. These two mycobactins are mixtures of compounds having the same nucleus but differing in their fatty side chains. The nucleus of mycobactin S has a chemical structure ...

Chlorine is a yellowish-green gas with a pungent, irritating odor. It is intermediate water-soluble and can cause acute damage to both upper and lower respiratory tracts. Its toxicity is thought to be mediated by the generation of hydrogen chloride upon contact with moist mucous membrane and by the formation of free radicals at the cellular level. Toxic exposures to chlorine were first reported...

This paper reviews various separation techniques used in purification processes to remove pollutants like carbon dioxide and hydrogen sulfide from petroleum products. The most effective include absorption, adsorption, cryogenic distillation, chemical looping combustion, membrane separation. study over 100 published studies assess their characteristics, benefits, drawbacks. choice of technology ...