The Experts below are selected from a list of 198 Experts worldwide ranked by ideXlab platform
S.s. Bako - One of the best experts on this subject based on the ideXlab platform.
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STUDIES ON SOLVENT EXTRACTION OF FREE Hydrogen Cyanide FROM RIVER WATER
Bulletin of The Chemical Society of Ethiopia, 2007Co-Authors: E.o. Ojeka, I. Adetoyi, S.s. BakoAbstract:A method for free and strongly complexed Cyanide measurement in river water was developed. Recovery tests from solution with and without river water, using various solvent combinations and background control were investigated to obtain an accurate and precise extraction method for the measurement of Hydrogen Cyanide in Kaduna River, Nigeria. The method enhanced the determination of undissociated Hydrogen Cyanide and the equilibria between Hydrogen Cyanide, Cyanide ion and complex Cyanides. A small portion of the Hydrogen Cyanide was extracted by equilibrating the sample with methylchloroform (1,1,1-trichloroethane), methanol, hexane and 2-octanol inclusions, respectively, in the solvent matrix with 2.5 M NaOH. The extracted Hydrogen Cyanide is transferred into tetrasodium pyrophosphate solution and determined colorimetrically. A total Cyanide concentration of 0.03 mg/L in the river water and 0.40 mg/L in an effluent water sample, respectively, were obtained by the proposed method compared to 0.020 and 0.45 mg/L from the established diffusion method. The proposed method was sensitive and reproducible in the range of 0 to 5 mgL -1 of Hydrogen Cyanide with detectable limit of about 0.01 mgL -1 . KEY WORDS : Solvent extraction; Free Hydrogen Cyanide; River water Bull. Chem. Soc. Ethiop. 2007 , 21(3), 305-313.
E.o. Ojeka - One of the best experts on this subject based on the ideXlab platform.
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STUDIES ON SOLVENT EXTRACTION OF FREE Hydrogen Cyanide FROM RIVER WATER
Bulletin of The Chemical Society of Ethiopia, 2007Co-Authors: E.o. Ojeka, I. Adetoyi, S.s. BakoAbstract:A method for free and strongly complexed Cyanide measurement in river water was developed. Recovery tests from solution with and without river water, using various solvent combinations and background control were investigated to obtain an accurate and precise extraction method for the measurement of Hydrogen Cyanide in Kaduna River, Nigeria. The method enhanced the determination of undissociated Hydrogen Cyanide and the equilibria between Hydrogen Cyanide, Cyanide ion and complex Cyanides. A small portion of the Hydrogen Cyanide was extracted by equilibrating the sample with methylchloroform (1,1,1-trichloroethane), methanol, hexane and 2-octanol inclusions, respectively, in the solvent matrix with 2.5 M NaOH. The extracted Hydrogen Cyanide is transferred into tetrasodium pyrophosphate solution and determined colorimetrically. A total Cyanide concentration of 0.03 mg/L in the river water and 0.40 mg/L in an effluent water sample, respectively, were obtained by the proposed method compared to 0.020 and 0.45 mg/L from the established diffusion method. The proposed method was sensitive and reproducible in the range of 0 to 5 mgL -1 of Hydrogen Cyanide with detectable limit of about 0.01 mgL -1 . KEY WORDS : Solvent extraction; Free Hydrogen Cyanide; River water Bull. Chem. Soc. Ethiop. 2007 , 21(3), 305-313.
Vinay Gupta - One of the best experts on this subject based on the ideXlab platform.
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Spectrophotometric determination of Hydrogen Cyanide in air using phloroglucinol
Fresenius Journal of Analytical Chemistry, 1990Co-Authors: Sulbha Amlathe, Vinay GuptaAbstract:A spectrophotometric determination of Hydrogen Cyanide in air is described. Hydrogen Cyanide from air is collected in dilute sodium hydroxide and then reacted with pyridine forming glutaconic aldehyde. The glutaconic aldehyde thus formed is subsequently coupled with aqueous phloroglucinol solution to form a polymethine red-violet dye having absorbance maxima at 540 nm. The colour system obeys Beer's law in the range of 0.45 to 3.6 mg/m3 of Hydrogen Cyanide (0.4 to 3.2 μg/g). Collection efficiency of absorbing solution, molar absorptivity and Sandell's sensitivity have been evaluated. All other important analytical parameters have been studied and applied for the determination/detection of Hydrogen Cyanide in air samples and cigarette smoke.
David Smith - One of the best experts on this subject based on the ideXlab platform.
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Exhaled breath Hydrogen Cyanide as a marker of early Pseudomonas aeruginosa infection in children with cystic fibrosis
ERJ Open Research, 2015Co-Authors: Francis J. Gilchrist, John Belcher, Andrew M. Jones, David Smith, Alan R. Smyth, Kevin W. Southern, Patrik Španěl, A. Kevin Webb, Warren LenneyAbstract:Hydrogen Cyanide is readily detected in the headspace above Pseudomonas aeruginosa cultures and in the breath of cystic fibrosis (CF) patients with chronic ( P. aeruginosa ) infection. We investigated if exhaled breath HCN is an early marker of P. aeruginosa infection. 233 children with CF who were free from P. aeruginosa infection were followed for 2 years. Their median (interquartile range) age was 8.0 (5.0–12.2) years. At each study visit, an exhaled breath sample was collected for Hydrogen Cyanide analysis. In total, 2055 breath samples were analysed. At the end of the study, the Hydrogen Cyanide concentrations were compared to the results of routine microbiology surveillance. P. aeruginosa was isolated from 71 children during the study with an incidence (95% CI) of 0.19 (0.15–0.23) cases per patient-year. Using a random-effects logistic model, the estimated odds ratio (95% CI) was 3.1 (2.6–3.6), which showed that for a 1- ppbv increase in exhaled breath Hydrogen Cyanide, we expected a 212% increase in the odds of P. aeruginosa infection. The sensitivity and specificity were estimated at 33% and 99%, respectively. Exhaled breath Hydrogen Cyanide is a specific biomarker of new P. aeruginosa infection in children with CF. Its low sensitivity means that at present, Hydrogen Cyanide cannot be used as a screening test for this infection. Exhaled Hydrogen Cyanide is a specific but insensitive biomarker of new P. aeruginosa infection in children with CF
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acetone ammonia and Hydrogen Cyanide in exhaled breath of several volunteers aged 4 83 years
Journal of Breath Research, 2007Co-Authors: Patrik Španěl, Kseniya Dryahina, David SmithAbstract:Original on-line measurements of acetone, ammonia and Hydrogen Cyanide in the exhaled breath of several volunteers within the age ranges 4-6 years and 60-83 years are reported and compared with previous data on volunteer cohorts covering ages 17-18 years and 20-60 years. The compiled data show that a significant statistical increase in breath ammonia occurs with increasing age, but that acetone and Hydrogen Cyanide do not vary greatly with age.
Patrik Španěl - One of the best experts on this subject based on the ideXlab platform.
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Exhaled breath Hydrogen Cyanide as a marker of early Pseudomonas aeruginosa infection in children with cystic fibrosis
ERJ Open Research, 2015Co-Authors: Francis J. Gilchrist, John Belcher, Andrew M. Jones, David Smith, Alan R. Smyth, Kevin W. Southern, Patrik Španěl, A. Kevin Webb, Warren LenneyAbstract:Hydrogen Cyanide is readily detected in the headspace above Pseudomonas aeruginosa cultures and in the breath of cystic fibrosis (CF) patients with chronic ( P. aeruginosa ) infection. We investigated if exhaled breath HCN is an early marker of P. aeruginosa infection. 233 children with CF who were free from P. aeruginosa infection were followed for 2 years. Their median (interquartile range) age was 8.0 (5.0–12.2) years. At each study visit, an exhaled breath sample was collected for Hydrogen Cyanide analysis. In total, 2055 breath samples were analysed. At the end of the study, the Hydrogen Cyanide concentrations were compared to the results of routine microbiology surveillance. P. aeruginosa was isolated from 71 children during the study with an incidence (95% CI) of 0.19 (0.15–0.23) cases per patient-year. Using a random-effects logistic model, the estimated odds ratio (95% CI) was 3.1 (2.6–3.6), which showed that for a 1- ppbv increase in exhaled breath Hydrogen Cyanide, we expected a 212% increase in the odds of P. aeruginosa infection. The sensitivity and specificity were estimated at 33% and 99%, respectively. Exhaled breath Hydrogen Cyanide is a specific biomarker of new P. aeruginosa infection in children with CF. Its low sensitivity means that at present, Hydrogen Cyanide cannot be used as a screening test for this infection. Exhaled Hydrogen Cyanide is a specific but insensitive biomarker of new P. aeruginosa infection in children with CF
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acetone ammonia and Hydrogen Cyanide in exhaled breath of several volunteers aged 4 83 years
Journal of Breath Research, 2007Co-Authors: Patrik Španěl, Kseniya Dryahina, David SmithAbstract:Original on-line measurements of acetone, ammonia and Hydrogen Cyanide in the exhaled breath of several volunteers within the age ranges 4-6 years and 60-83 years are reported and compared with previous data on volunteer cohorts covering ages 17-18 years and 20-60 years. The compiled data show that a significant statistical increase in breath ammonia occurs with increasing age, but that acetone and Hydrogen Cyanide do not vary greatly with age.
