Iodate

About: Iodate is a research topic. Over the lifetime, 2284 publications have been published within this topic receiving 37333 citations.

A modeling study of iodine chemistry in the marine boundary layer

Abstract: An observationally constrained photochemical box model has been developed to investigate the atmospheric chemistry of iodine in the marine boundary layer, motivated by recent measurements of the iodine monoxide (IO) radical (Allan et al., this issue). Good agreement with the time series of IO measured at a midlatitude coastal station was achieved by using a reaction scheme that included recycling of iodine through marine aerosol. The strong diurnal variation in IO observed in the subtropical Atlantic was satisfactorily modeled by assuming a constant concentration of iodocarbons that photolyzed to produce roughly 1×104 iodine atoms cm−3 s−1 at midday. The significance of the occurrence of IO at concentrations of up to 4 parts per trillion in the marine boundary layer was then considered from three angles. First, the iodine-catalyzed destruction of ozone was shown to be of a magnitude similar to that caused by odd-hydrogen photochemistry, with up to 13% of the available ozone destroyed per day in a marine air mass. Second, the enrichment factor of iodine in marine aerosol compared with surface seawater was predicted to increase to values of several thousand, in sensible accord with observations. Most of the enrichment should be due to the accumulation of iodate, although other iodine species may also be present, depending on the rate of aerosol recycling. Third, the denoxification of the marine boundary layer was found to be significantly enhanced as a result of aerosol uptake of IONO2, formed from the recombination of IO with NO2.

Electrochemical determination of nitrite and iodate by use of gold nanoparticles/poly(3-methylthiophene) composites coated glassy carbon electrode

Abstract: A promising electrochemical sensor was fabricated by electrodeposition of gold nanoparticles on poly(3-methylthiophene) (P3MT)-modified glassy carbon electrode (GCE), forming a nano-Au/P3MT composites-modified GCE (nano-Au/P3MT/GCE). Field emission scanning electron microscope (FE-SEM) and electrochemical techniques were used for the characterization of these composites. It was found that nano-Au/P3MT layer was very uniform, and formed a kind of nanoporous structure. Electrochemical experiments showed that this proposed nano-Au/P3MT composites-modified electrode exhibited excellent electrocatalytic properties for nitrite and iodate. Amperometry revealed that there existed a good linear relationship between peak current with the concentration in the range of 10–1000 μM and the detection limit of 2.3 μM for nitrite and in the range of 5–500 μM and the detection limit of 1.4 μM for iodate. The proposed method has been used as an amperometric detector for analysis of nitrite and iodate in iodized table salt and results were satisfactory. The nano-Au/P3MT composites-modified electrode had good storage stability, reproducibility and anti-interference ability for promising practical application.