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John H. Pavlish - One of the best experts on this subject based on the ideXlab platform.
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On the analysis of Mercuric Nitrate in flue gas by GC–MS
Analytical and Bioanalytical Chemistry, 2002Co-Authors: Edwin S. Olson, Ramesh K. Sharma, John H. PavlishAbstract:Recent research has demonstrated that in a simulated flue gas stream containing NO_2 and SO_2 elemental mercury is initially captured on a carbon or manganese oxide sorbent. After approximately an hour, however, mercury breaks through relatively rapidly, and the volatile form of mercury emitted is an oxidized species. The volatile mercury species emitted from a granular MnO_2 sorbent was trapped in an impinger containing cold acetonitrile. Subsequent evaporation of 95% of the acetonitrile in a Kuderna–Danish apparatus and gas chromatography (GC) of the concentrate resulted in a single mercury-containing GC peak at 5.5 min; the retention time and mass spectrum of this compound matched exactly those of a standard mercury(II) Nitrate hydrate, Hg(NO_3)_2.H_2O dissolved in acetonitrile. The volatile mercury component analyzed from injection of this standard solution was shown to be a form of methylmercury that is produced in the GC column by reaction of the highly reactive mercury Nitrate with the methylsiloxane GC phase. Because the on-column derivatization reaction seems to be unique to mercury Nitrate, the GC–MS (gas chromatography–mass spectroscopic) analysis provides strong evidence for identification of the trapped oxidized mercury species as mercury Nitrate although, because the Nitrate becomes detached from the mercury atom in the on-column reaction, the identity is not proven.
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on the analysis of Mercuric Nitrate in flue gas by gc ms
Analytical and Bioanalytical Chemistry, 2002Co-Authors: Edwin S. Olson, Ramesh K. Sharma, John H. PavlishAbstract:Recent research has demonstrated that in a simulated flue gas stream containing NO2 and SO2 elemental mercury is initially captured on a carbon or manganese oxide sorbent. After approximately an hour, however, mercury breaks through relatively rapidly, and the volatile form of mercury emitted is an oxidized species. The volatile mercury species emitted from a granular MnO2 sorbent was trapped in an impinger containing cold acetonitrile. Subsequent evaporation of 95% of the acetonitrile in a Kuderna–Danish apparatus and gas chromatography (GC) of the concentrate resulted in a single mercury-containing GC peak at 5.5 min; the retention time and mass spectrum of this compound matched exactly those of a standard mercury(II) Nitrate hydrate, Hg(NO3)2.H2O dissolved in acetonitrile. The volatile mercury component analyzed from injection of this standard solution was shown to be a form of methylmercury that is produced in the GC column by reaction of the highly reactive mercury Nitrate with the methylsiloxane GC phase. Because the on-column derivatization reaction seems to be unique to mercury Nitrate, the GC–MS (gas chromatography–mass spectroscopic) analysis provides strong evidence for identification of the trapped oxidized mercury species as mercury Nitrate although, because the Nitrate becomes detached from the mercury atom in the on-column reaction, the identity is not proven.
Edwin S. Olson - One of the best experts on this subject based on the ideXlab platform.
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On the analysis of Mercuric Nitrate in flue gas by GC–MS
Analytical and Bioanalytical Chemistry, 2002Co-Authors: Edwin S. Olson, Ramesh K. Sharma, John H. PavlishAbstract:Recent research has demonstrated that in a simulated flue gas stream containing NO_2 and SO_2 elemental mercury is initially captured on a carbon or manganese oxide sorbent. After approximately an hour, however, mercury breaks through relatively rapidly, and the volatile form of mercury emitted is an oxidized species. The volatile mercury species emitted from a granular MnO_2 sorbent was trapped in an impinger containing cold acetonitrile. Subsequent evaporation of 95% of the acetonitrile in a Kuderna–Danish apparatus and gas chromatography (GC) of the concentrate resulted in a single mercury-containing GC peak at 5.5 min; the retention time and mass spectrum of this compound matched exactly those of a standard mercury(II) Nitrate hydrate, Hg(NO_3)_2.H_2O dissolved in acetonitrile. The volatile mercury component analyzed from injection of this standard solution was shown to be a form of methylmercury that is produced in the GC column by reaction of the highly reactive mercury Nitrate with the methylsiloxane GC phase. Because the on-column derivatization reaction seems to be unique to mercury Nitrate, the GC–MS (gas chromatography–mass spectroscopic) analysis provides strong evidence for identification of the trapped oxidized mercury species as mercury Nitrate although, because the Nitrate becomes detached from the mercury atom in the on-column reaction, the identity is not proven.
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on the analysis of Mercuric Nitrate in flue gas by gc ms
Analytical and Bioanalytical Chemistry, 2002Co-Authors: Edwin S. Olson, Ramesh K. Sharma, John H. PavlishAbstract:Recent research has demonstrated that in a simulated flue gas stream containing NO2 and SO2 elemental mercury is initially captured on a carbon or manganese oxide sorbent. After approximately an hour, however, mercury breaks through relatively rapidly, and the volatile form of mercury emitted is an oxidized species. The volatile mercury species emitted from a granular MnO2 sorbent was trapped in an impinger containing cold acetonitrile. Subsequent evaporation of 95% of the acetonitrile in a Kuderna–Danish apparatus and gas chromatography (GC) of the concentrate resulted in a single mercury-containing GC peak at 5.5 min; the retention time and mass spectrum of this compound matched exactly those of a standard mercury(II) Nitrate hydrate, Hg(NO3)2.H2O dissolved in acetonitrile. The volatile mercury component analyzed from injection of this standard solution was shown to be a form of methylmercury that is produced in the GC column by reaction of the highly reactive mercury Nitrate with the methylsiloxane GC phase. Because the on-column derivatization reaction seems to be unique to mercury Nitrate, the GC–MS (gas chromatography–mass spectroscopic) analysis provides strong evidence for identification of the trapped oxidized mercury species as mercury Nitrate although, because the Nitrate becomes detached from the mercury atom in the on-column reaction, the identity is not proven.
Bhart Indu - One of the best experts on this subject based on the ideXlab platform.
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Influence of Mercuric Nitrate on Species and Reactions Related to Chlorine Dioxide Formation
Industrial & Engineering Chemistry Research, 1997Co-Authors: Bhart Indu, M. Fazlul Hoq, W. R. ErnstAbstract:Mercuric ions influence reactions and intermediates that are involved in forming chlorine dioxide from chlorate ions. Addition of Mercuric ions to reaction solutions can aid in understanding the mechanism and kinetics of this system. Mercuric ions do not react with aqueous solutions of chlorine dioxide unless those solutions contain chlorous acid. This unusual effect has enabled us to confirm that chlorous acid is an intermediate in the formation of chlorine dioxide in the methanol−chlorate reaction. This work discusses the effect of Mercuric ions on solutions containing various Cl species (chlorine, chlorine dioxide, chlorous acid, and both chlorine dioxide and chlorous acid) and on reactions that involve these same species. The work also explores the methanol−chlorate reaction in the absence of Mercuric ions. In the initial stage of the process, chlorine dioxide forms after an induction period, during which an intermediate rapidly forms, maximizes in concentration, and then disappears, and a second inte...
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Reaction of methanol with chlorate ions in acid solution containing Hg+2 by NMR
AIChE Journal, 1996Co-Authors: William R. Ernst, Bhart Indu, Brian Crump, Leslie T. GelbaumAbstract:The reaction rate of methanol was measured in solutions of sodium chlorate and sulfuric acid at several levels of temperature and concentration, in the presence of Mercuric Nitrate. The progress of the reaction was monitored by proton NMR signals corresponding to methanol and formic acid. Chlorine dioxide formation was suppressed by adding Mercuric Nitrate, which was shown earlier to catalyze the disproportionation of the intermediate species, chlorous acid, and sequester chloride ions. The reaction is first order in methanol and chlorate concentration and in the Hammett acidity function. The reaction of formic acid, sodium chlorate and sulfuric acid was also studied using the same technique. Formic acid was stable and did not react with chlorate at a measurable rate, even at concentrations and temperatures of a commercial process. This study related to commercial processes that produce chlorine dioxide by reducing chlorate ions with methanol. Chlorine dioxide is an oxidizing chemical that is used in water purification and is replacing chlorine in many chemical bleaching processes because of environmental concerns.
Gang Deng - One of the best experts on this subject based on the ideXlab platform.
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Synthesis of α‑Diketones from Alkylaryl- and Diarylalkynes Using Mercuric Salts
2015Co-Authors: Michael E. Jung, Gang DengAbstract:Both alkylarylalkynes and diarylalkynes 1 are converted into the α-diketones 2 in good yield by the use of Mercuric salts, e.g., Mercuric Nitrate hydrate or Mercuric triflate, in the presence of water. Other Mercuric salts, e.g., sulfate, chloride, acetate, or trifluoroacetate, do not provide the diketone product. A possible mechanism is proposed
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Synthesis of α-diketones from alkylaryl- and diarylalkynes using Mercuric salts.
Organic letters, 2014Co-Authors: Michael E. Jung, Gang DengAbstract:Both alkylarylalkynes and diarylalkynes 1 are converted into the α-diketones 2 in good yield by the use of Mercuric salts, e.g., Mercuric Nitrate hydrate or Mercuric triflate, in the presence of water. Other Mercuric salts, e.g., sulfate, chloride, acetate, or trifluoroacetate, do not provide the diketone product. A possible mechanism is proposed.
R. J. Pinney - One of the best experts on this subject based on the ideXlab platform.
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Epidemiology and susceptibilities to mercury preservatives of staphylococci isolated from used eye-drops preserved with thiomersal.
The Journal of pharmacy and pharmacology, 1995Co-Authors: S. K. Du Bois, A. L. Davison, R. J. PinneyAbstract:Minimum inhibitory concentrations (MICs) of seven independent isolates of Staphylococcus hominis isolated in the same week from used eye-drops, preserved with thiomersal and collected from wards and clinics in the same hospital, ranged between 1 and 0·03 mg L−1 for thiomersal, 1 and 0·01 mg L−1 for phenyl Mercuric Nitrate and 10 and 3 mg L−1 for Mercuric chloride. Although MIC values determined on solid nutrient medium indicated a 100-fold variation in susceptibility to the bacteriostatic effect of phenyl Mercuric Nitrate, after 5 h in an aqueous solution containing the bactericidal concentration of 10 mg L−1 phenyl Mercuric Nitrate, the survival levels of the six S. hominis isolates were similar, with a mean of 13·4% (s.d. 11·0), compared with 100 and 0·8%, respectively, for the most resistant and most sensitive control staphylococcal strains tested. Antibiotic susceptibilities and plasmid profiles of the S. hominis isolates indicated they were the same strain. It is concluded that laboratory indicators of preservative efficacy, such as MIC determination or susceptibility to bactericidal concentrations of preservatives, do not necessarily correlate with the epidemiology of contaminating bacterial strains or their survival in preserved pharmaceuticals.