Processing Metallic Bismuth to Produce Citrate

Theoretical Foundations of Chemical Engineering - Using chemical and XRD phase analysis, along with electron microscopy, the hydrolytic processing of metallic bismuth into high-purity citrate has...     

Caries prevalence in preschool children in industrial cities

Caries incidence was analyzed in preschool children attending kindergartens living in two industrial towns differing by the level and specific features of air pollution and by fluorine levels in potable water. Caries incidence was found to be higher in a ferrous metallurgy center with very low (0.1 to 0.3 ml/l) fluorine levels in potable water. Passive smoking factor was found to contribute to development of caries in children, particularly so in girls. Motor car transport effects on caries development in children were not confirmed. Recommendations on reduction of caries development intensity are suggested.     

Processing of Metallic Bismuth with the Production of Bismuth Oxohydroxotribromophenolate

The hydrolytic processing of metallic bismuth with the production of bismuth oxohydroxotribromophenolate pharmacopeial composition [Bi₆O₆(OH)₂](C₆H₂Br₃O)₄ used to prepare the medical drug Xeroform was studied by chemical, X-ray diffraction, and thermogravimetric analyses and electron microscopy. The results of these studies were confirmed by the industrial tests of the developed technology based on the oxidation of metallic bismuth, the dissolution of synthesized technical oxide in nitric acid, the hydrolytic purification of bismuth from impurity metals by aqueous alkaline hydrolysis with the precipitation of bismuth in the form of oxohydroxonitrate [Bi₆O₄(OH)₄](NO₃)₆?H₂O, the dissolution of bismuth oxohydroxonitrate in nitric acid, and the synthesis of bismuth oxohydroxotribromophenolate by adding an aqueous sodium tribromophenolate solution to the resulting solution in the presence of sodium acetate at a pH of 6.5–7.5 and a temperature of 90–95°C.