The quenching constant for the iodide quenching of the fluorescence of riboflavin phosphate was measured at pH 5 and at pH 8. The value of the constant at the lower pH (where the phosphate group is unionized), k' = 23 M~ , was independent of the ionic strength, |i. The ratio k"/k' = f (k" the quenching constant at pH 8, where the phosphate group carries a single negative charge) was found to he...

Abstract. The speciation of soluble iodine and major-ion composition were determined in size-fractionated aerosols collected during the AMT21 cruise between Avonmouth, UK, Punta Arenas, Chile, September–November 2011. proportions species (iodide, iodate organic (SOI)) varied markedly size fractions with extent to which samples influenced by pollutants. In general, fine mode (< 1 µm) containe...

D-Galactose, Nessler's Reagent The present paper deals with the kinetics of oxidation of D-galactose by Nessler's reagent in alkaline medium. The reaction is zero order with respect to Hg(II) and first order with respect to reducing sugar. The direct proportionality of the reaction rate at low hydroxide ion concentrations shows retarding trend at higher concentrations. The reaction rate is inve...

m-Iodosylbenzoic acid performs iodinations of arenes in the presence of iodine at room temperature in acetonitrile. Separation of pure products is conveniently achieved by scavenging any aryl iodide by ion exchange with IRA-900 (hydroxide form). The reduced form of the reagent, m-iodobenzoic acid, can be easily recovered from the ion exchange resin or from the basic aqueous solution by simple a...

The properties of dry collodion membranes previously described allow the prediction that cells of these membranes will concentrate solutes under certain conditions. Three such cases have been studied experimentally. 1. A membrane containing thiosulphate and immersed in a solution of iodine concentrates iodide ion. 2. A membrane containing sodium chromate and immersed in mercury chloride concent...

We propose an automated method for the routine analysis of urinary iodide, using paired-ion reversed-phase HPLC with electrochemical detection and a silver working electrode. Assay conditions include a flow rate of 1.0 mL/min and an operating potential of 0.10 V. The retention time for iodide is 5.4 min. Sample preparation can be semiautomated by use of a reduced-pressure manifold. The detectio...

The asymmetric units for the salts 4-(4-fluoro-phen-yl)-1-isopropyl-1,2,4-triazol-1-ium iodide, C11H13FN3 (+)·I(-), (1), 1-isopropyl-4-(4-methyl-phen-yl)-1,2,4-triazol-1-ium iodide, C12H16N3 (+)·I(-), (2), 1-isopropyl-4-phenyl-1,2,4-triazol-1-ium iodide, C11H14N3 (+)·I(-), (3), and 1-methyl-4-phenyl-1,2,4-triazol-1-ium iodide, C9H10N3 (+)·I(-), (4), contain one cation and one iodide ion, wherea...

Donor-acceptor [2]catenanes based on cyclobis(paraquat-p-phenylene) as the pi-acceptor ring have been used prominently in the construction of functional molecular devices. We report here their thermodynamically controlled synthesis from isolated pi-donor and pi-acceptor rings under the catalytic influence of tetra butylammonium iodide. The initial nucleophilic attack of iodide ion, which opens ...