Journal of the American Chemical Society is published by the American Chemical Society. 1155 Sixteenth Street N.W., Washington, DC 20036 Systematic design of chemical oscillators. 17. Birhythmicity and compound oscillation in coupled chemical oscillators: chlorite-bromate-iodide system Mohamed Alamgir, and Irving R. Epstein J. Am. Chem. Soc., 1983, 105 (8), 2500-2502• DOI: 10.1021/ja00346a080 •...

Four sensitive and rapid methods for the determination of stavudine (STV) in bulk drug and in dosage forms were developed and optimized. In titrimetry, aqueous solution of STV was treated with a known excess of bromate-bromide in HCl medium followed by estimation of unreacted bromine by iodometric back titration. Spectrophotometric methods involve the addition of a measured excess of bromate-br...

Human hair keratin films were used in order to examine the e#ects of reducing and oxidizing agents. Thioglycolic acid and sodium bromate were employed as reducing and oxidizing agents, respectively. The white and opaque appearance of the keratin films turned transparent as the concentration of thioglycolic acid increased. However, when followed by the oxidizing treatment, the keratin films retu...

A Gram-negative, facultatively anaerobic, rod-shaped, dissimilatory chlorate-reducing bacterium, strain AW-1(T), was isolated from biomass of an anaerobic chlorate-reducing bioreactor. Phylogenetic analysis of the 16S rDNA sequence showed 100% sequence similarity to Pseudomonas stutzeri DSM 50227 and 98.6% sequence similarity to the type strain of P. stutzeri (DSM 5190(T)). The species P. stutz...

The study of oscillating chemical reactions has been dominated by the Belousov-Zhabotinskii (BZ) reaction. It is also called the chemical clock, which is similar to the biological clock. When the chemical reaction is far from equilibrium, the concentration of some substances in the reaction system exhibits a regular change with time, a kind of self-regulating function similar to what happens in...

Tetrabromobisphenol A (TBBPA) is one of the most widely used brominated flame retardants and has attracted more and more attention. In this work, the parent TBBPA with an initial concentration of 100 mg/L was completely removed after 6 min of ozonation at pH 8.0, and alkaline conditions favored a more rapid removal than acidic and neutral conditions. The presence of typical anions and humic aci...

One titrimetric and two indirect spectrophotometric methods are described for the determination of doxycycline hyclate (DCH) in bulk drug and in its formulations. The methods use bromate-bromide, methyl orange and indigo carmine as reagents. In titrimetry (method A), DCH is treated with a known excess of bromate-bromide mixture in acid medium and the residual bromine is back titrated iodometric...

A new polyoxometalate(POM)-templated inorganic-organic hybrid compound, [Ag6(trz)6][PMo12O40]2 · 6H2O (1) (trz = 1,2,4-triazole) has been prepared under hydrothermal conditions and characterized by single-crystal X-ray diffraction, elemental analyses, IR spectroscopy, thermogravimetric analysis and cyclic voltammetry. In compound 1, six Ag+ ions are linked by six trz molecules to give a hexanuc...

BACKGROUND Exposure to bisphenol A (BPA) has been reported to alter global gene expression, induce epigenetic modifications, and interfere with complex regulatory networks of cells. In addition to these reprogramming events, we have demonstrated that BPA exposure generates reactive oxygen species and promotes cellular survival when co-exposed with the oxidizing agent potassium bromate (KBrO3). ...

Autonomic materials are those that automatically respond to a change in environmental conditions, such as temperature or chemical composition. While such materials hold incredible potential for a wide range of uses, their implementation is limited by the small number of fully-developed material systems. To broaden the number of available systems, we have developed a post-functionalization techn...