• Title/Summary/Keyword: Bromide ion

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Environmental and biological monitoring of workers exposed to methyl bromide through quarantine fumigation (방역작업자의 브롬화메틸(methyl bromide) 노출수준과 생물학적 모니터링)

  • Lee, Jong-Seong;Lee, Yong-Hag;Shin, Jae-Hoon;Choi, Jung-Keun;O, Cha-Jae;Jung, Ho-Keun
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.11 no.3
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    • pp.212-218
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    • 2001
  • This study was performed to estimate environmental and biological monitoring of workers exposed to methyl bromide through quarantine fumigation. Airborne methyl bromide and it's metabolites were analyzed by gas chromatography and ion chromatography, respectively. The results are as followings; airborne concentration of methyl bromide(TWA) was $2.08{\pm}1.56ppm$(N=8). Dispersion and setting/degas groups were $0.67{\pm}0.12ppm$(N=2) and $2.54{\pm}1.53ppm$(N=6), respectively. Bromide ion concentration in serum was $23.40{\pm}14.91mg/{\ell}$(N=10) in the exposed workers and $4.74{\pm}0.82mg/{\ell}$(N=21) in the non-exposed workers. Bromide ion concentration in urine was $35.56{\pm}26.89mg/{\ell}$(N=11) in exposed group and $6.62{\pm}2.31mg/{\ell}$(N=21) in non-exposed group. Good correlation was observed between concentration of serum and urine ($r^2$=0.890 p<0.01). No significant correlations of other determinants were observed. Calculated from a regressive curve, the biological half lifes of serum and urine were 10.7 and 5.9 days. In these results, biological monitoring of bromide ion of serum and urine provided useful information for evaluating exposure of workers to methyl bromide, so that an availability of bromide ion of biological samples was showed as biological monitoring indices for methyl bromide.

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Characteristics of ammonia ozonation with bromide (브롬촉매에 의한 암모니아의 오존산화시 특성)

  • 박문숙;양미경
    • Journal of environmental and Sanitary engineering
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    • v.17 no.2
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    • pp.1-10
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    • 2002
  • Ammonia is used in the manufacture of fertilizers, refrigerants, stabilizers and many household cleaning agents. The wide applications result in ammonia contamination in water. Ammonia can be removed from water by physical, biological, and chemical methods. Especially ozonation is effective in the treatment of water with low concentration of ammonia. Therefore, this study is undertaken to provide kinetic data for the ozonation of ammonia with bromide. The results were as follows; Ammonia oxidized by ozone with bromide catalysis. The denitrification rate of the ammonia increased proportionally to the concentration of bromide, and the overall reaction order was zero. It was also found that the effect of bromide ion concentration on the denitrification can be expressed by Monod type equation and there was no more effect above a proper bromide ion concentration. The reacted ammonia was converted completely to nitrate ion without bromide, but the denitrification of ammonia by ozone was conducted in the presence of bromide.

Liquid Chromatography of Aromatic Sulfonic Acids by Tetramethylammonium Bromide (Tetramethylammonium Bromide를 이용한 방향족 술폰산들의 액체크로마토그래피)

  • Oh, Hae-Beom
    • Journal of the Korean Chemical Society
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    • v.37 no.9
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    • pp.793-799
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    • 1993
  • Ion-pair model was predominated over ion-interaction model in the retention mechanism of analytes when tetramethylammonium bromide (TMAB) was used as a counter-ion in the investigation of aromatic sulfonic acids on the reversed-phase liquid chromatography by $C_{18}$ column as a stationary phase. The capacity factors of analytes were influenced by the type and concentration of counter-ions, concentrations of methanol and co-anion, types and position of functional group, and the pH mobile phase. Components of analyte mixture could be separated under the optimum conditions by this method.

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Kinetic Studies on the Mechanism of Hydrolysis of Benzohydrazonyl Bromide (Benzohydrazonyl Bromide의 加水分解 反應메카니즘에 관한 反應速度論的 硏究)

  • Ki Sung Kwon;Tae Rin Kim
    • Journal of the Korean Chemical Society
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    • v.20 no.3
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    • pp.221-228
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    • 1976
  • The kinetics of hydrolysis of hydrazonyl bromides $(p-H,\;p-CH_3,\;p-OCH_3,\;p-Br,\;p-Cl\;&\;p-NO_2)$ have been investigated by UV spectrometry in $60{\%}$ dioxane-water at $25^{\circ}C$ and a rate equation which can be applied over wide pH range was obtained. Below pH2, the rate of hydrolysis of a series of hydrazonyl bromide is accelerated by electrondonating group (${\rho}$ = -0. 94) whereas at the pH values greater than 4, the ${\rho}$-value is 0.54. The rate equation, solvent-, substituent-and bromide ion-effect on the rate of hydrolysis are rationalized in terms of $S_N1$ and $S_N2$ mechanism: below pH 2, the hydrolysis proceed through $S_N2$, however, above pH 4, the hydrolysis is started by the attack of hydroxide ion and in the range pH 2{\sim}$4, these two reactions occur competitively.

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Microanalysis of Pancuronium Bromide in Urine and Blood by HPLC (HPLC를 이용한 뇨 및 혈액중의 Pancuronium Bromide의 미량분석)

  • 김박광;김양숙;박성배;이종숙;정규혁;김경님
    • YAKHAK HOEJI
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    • v.37 no.1
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    • pp.30-35
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    • 1993
  • HPLC/fluorescence detection method for the analysis of pancuronium bromide in biological fluids was developed. The method depends on the formation of insoluble red complex between pancuronium bromide and rose bengal in aqueous layer. This complex is quantitatively extracted from aqueous layer into chloroform layer. The complex is stable for 1 day in chloroform layer at room temperature. It was possible to analyze pancuronium bromide in the range of 0.05~0.5 $\mu\textrm{g}$/ml without the effect of co-prescribed drugs.

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Exposure Assessment of Biological Monitoring by Urinary Bromide Ion in Methyl Bromide Fumigation Workers (메틸브로마이드 훈증제 작업자의 요 중 브로마이드 이온을 이용한 생물학적 노출평가)

  • Seo, Jeong-Wook;Kim, Byoung-Gwon;Kim, Yu-mi;Lee, Se-Young;Kim, Na-Young;Lim, Hyoun-Ju;Gu, Dongchul;Hong, Young-Seoub
    • Journal of Environmental Health Sciences
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    • v.45 no.6
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    • pp.675-687
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    • 2019
  • Objective: Methyl bromide (MB) fumigant has been shown to be fatal to human when was exposed. However, it were still used the significant amount in quarantine disinfection sites. The purposes of this study were to assess the MB exposure status and characteristics by fumigation-related workers and to provide supporting data for management plan. Methods: For this study, the three groups related to fumigation work were composed. A total of 107 workers were directly exposed, 20 field inspectors were indirect, and 20 general quarantines were not exposed. The urinary bromide ion concentrations in each group were analyzed by using HPLC/ICP-MS, and the working characteristics were identified using the structured questionnaire. Results: The urinary bromide ion concentration in the exposed group of fumigation workers was higher than the indirect and non-exposed groups. In the work characteristics of workers, there was a significant tendency to increase urinary bromide ion concentrations with higher fumigation work years (≤4 years: 2.84 (1.13-7.11) mg/g cr, >4-15 years: 5.36 (4.37-6.57) mg/g cr, >15-37 years: 6.69 (5.27-8.49) mg/g cr, p=0.034). In the comparison of the average number of working days per month, the more working days, the higher the urinary bromide ion concentration was statistically significant (≤12.5 days: 2.59 (1.19-5.65) mg/g cr, >12.5-19.25 days: 5.46 (4.62-6.44) mg/g cr, >19.25-27.25 days: 7.93 (5.93-10.59) mg/g cr, p=0.002). Conclusion: This study was the first nationwide survey including biological monitoring in workers exposed to methyl bromide. The results of this study were expected to be used as a reference for workers' health rights in relation to fumigation, prevention of addiction accidents, and safe management plan.

Sensitive Determination of Pinaverium Bromide in Human Plasma by LC-ESI-MS/MS : Applicability to Oral Bioavailability Determination (LC-ESI-MS/MS를 이용한 생체시료 중 브롬화피나베리움의 고감도 분석 및 이를 이용한 생체이용률 평가)

  • Park, Seok;Lee, Ye-Rie;Kim, Ho-Hyun;Lee, Hee-Joo;Kim, Yoon-Gyoon;Youm, Jeong-Rok;Han, Sang-Beom
    • Journal of Pharmaceutical Investigation
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    • v.34 no.6
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    • pp.513-519
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    • 2004
  • A sensitive method for quantification of pinaverium bromide in human plasma was established using liquid chromatography-electrospray ionization tandem mass spectrometry(LC-ESI-MS/MS). Glimepiride was used as internal standard. Pinaverium bromide and internal standard in plasma sample were extracted using tert-butylmethylether(TBME). A centrifuged upper layer was then evaporated and reconstituted with mobile phase of acetonitrile-5 mM ammonium formate (80/20, pH 3.0). The reconstituted samples were injected into a $C_{18}$ reversed-phase column. Using MS/MS with multiple reaction monitoring (MRM) mode, pinaverium and glimepirde were detected without severe interference from human plasma matrix. Pinaverium produced a protonated precursor ion $([M+H]^+)$ at m/z 510.3 and a corresponding product ion at m/z 228.9. Internal standard produced a protonated precursor ion $([M+H]^+)$ at m/z 491.5 and a corresponding product ion at m/z 352.0. Detection of pinaverium bromide in human plasma was accurate and precise, with limit of quantitation at 0.5 ng/ml. The method has been successfully applied to bioavailability study of pinaverium bromide tablet in Korean healthy male volunteers. Pharmacokinetic parameters such as $AUC_t,\;C_{max},\;T_{max},\;K_{el}\;and\;t_{1/2}$ were calculated.

Determination of bromide in bottled mineral water and ground water in Korea (먹는 샘물 및 지하수 원수 중 bromide 분석연구)

  • Ahn, Hye-Sil;Seo, Kyoung-Ae;Park, Ju-Hyun;Lee, Jun-Bae;Kim, Tae-Seung;Han, Jin-Seok;Kwon, Oh-Sang
    • Analytical Science and Technology
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    • v.24 no.1
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    • pp.10-14
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    • 2011
  • This study was performed to compare international analytical methods of bromide and applied to determine bromide in bottled mineral water and raw ground water in Korea. Bromide in water was eluted by 10~50 mM potassium hydroxide (KOH) and determined by ion chromatography-suppressed conductivity detector (IC-CD). Sample was purified with Ba- and H-on-guard cartridge and $0.2\;{\mu}m$ membrane filter. The method detection limit (MDL) and the limit of quantitation (LOQ) of bromide were 0.2 and $0.5\;{\mu}g/L$, respectively. The calibration curve showed good lineality above 0.9993 in the ranges of the $0.5\sim80\;{\mu}g/L$. A correlation coefficient of bromide in ground water and sum of bromide and bromate in bottled mineral water is 0.808.

Halogen Exchange Reactions of Benzyl Halides (Part I) Kinetics of Reactions of Chloride and Bromide Ions with Benzyl Chloride and Bromide (벤질할라이드의 할로겐交煥反應 (第 1 報) 鹽化 및 臭化 벤질과 鹽素 및 臭素이온과의 反應速度)

  • Jung, Kyung-Hoon;Huh, Yeon;Lee, Ik-Choon
    • Journal of the Korean Chemical Society
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    • v.9 no.3
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    • pp.148-151
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    • 1965
  • Kinetics of reactions of chloride and bromide ions with benzyl chloride and bromide have been investigated in 90% ethanol solution. Semi-quantitative analysis of the results shows that the bond-formation is more important than the bond-breaking and furthermore in bond-formation the energy gain due to bond-formation is less than the increase in electron affinity of the nucleophile.

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Stoichiometry of Hydrazine-Bromate Reaction in Acid Media

  • Choi, Q.Won;Jung, Jin
    • Journal of the Korean Chemical Society
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    • v.15 no.4
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    • pp.183-189
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    • 1971
  • Stoichiometry of hydrazine-bromate reaction has been studied in acid media of varying compositions, elucidating the effects of bromide and chloride ions in sulfuric acid, perchloric acid, hydrochloric acid, and hydrobromic acid at varying concentrations of hydrogen ion and cupric ion. The study shows that the number of red-ox equivalent consumed by one mole of hydrazine becomes practically 4.00 if the concentrations of bromide and hydrogen ions are kept higher than 0.1M and 6M, respectively. The presence of copper tends to reduce the bromate consumption by hydrazine in an irregular manner, but such an effect becomes unimportant if the concentrations of bromide and hydrogen ions are kept sufficiently high.

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