建立液液萃取气相色谱法测定饮用水中二氯一溴甲烷和一氯二溴甲烷的方法。在200 m L水样中加入26g硫酸钠,以正己烷为萃取剂,用DB–5毛细管柱进行分离,以电子捕获检测器进行检测。二氯一溴甲烷和一氯二溴甲的质量浓度在0~50μg/L范围内...建立液液萃取气相色谱法测定饮用水中二氯一溴甲烷和一氯二溴甲烷的方法。在200 m L水样中加入26g硫酸钠,以正己烷为萃取剂,用DB–5毛细管柱进行分离,以电子捕获检测器进行检测。二氯一溴甲烷和一氯二溴甲的质量浓度在0~50μg/L范围内与色谱峰面积均呈良好的线性,线性相关系数大于0.999,检出限均为0.01μg/L。水样加标回收率在92.4%~102.5%之间,测定结果的相对标准偏差均小于3%(n=7)。该方法操作简便,灵敏度高,适用于生活饮用水中二氯一溴甲烷和一氯二溴甲烷的测定。展开更多
在 F22热溴化反应中,氯的存在有利于产物二氟氯溴甲烷(简称1211)的生成。1971年德国 Pauchsch Heinrich 等人也作了类似的报导。1978年还发现,随着反应管径的增大,通入氯的效果更加明显。促使把它作为1211生产的一项放大技术加以进一步...在 F22热溴化反应中,氯的存在有利于产物二氟氯溴甲烷(简称1211)的生成。1971年德国 Pauchsch Heinrich 等人也作了类似的报导。1978年还发现,随着反应管径的增大,通入氯的效果更加明显。促使把它作为1211生产的一项放大技术加以进一步的研究,并对其加速生成1211的反应机理作了探讨。展开更多
It is investigated the interaction of Ge（IV） with bis（2,3,4-trigodroksifenolazo） benzidine （R） in the presence of KSAS （cationic surface active substances）-CPCl （cetylpyridinium chloride）, CPBr （cetylpyridi...It is investigated the interaction of Ge（IV） with bis（2,3,4-trigodroksifenolazo） benzidine （R） in the presence of KSAS （cationic surface active substances）-CPCl （cetylpyridinium chloride）, CPBr （cetylpyridinium bromide） and CTMABr （cetyltrimethylammonium bromide）. It is studied the effect pH, time on the formation of ternary complexes. It is determinated of molar absorption coefficients and stability constants of germanium. Binary （Ge-R） and triple （Ge-R-CPCI, Ge-R-CPBr, Ge-R-CTMaBr） complex form at pH 4 and pH 1, respectively. The composition proportion of binar system is 1：2 and the composition proportion triple complex is 1：1：2. The concentration interval of germanium which obeying beer low in the Ge-R 0.12-2.92 mkq/mL, in the Ge-R-CPCI is 0.04-1.46 mkq/mL, in the Ge-R-CPBr is 0.00-1.00 mkq/mL and in the Ge-R-CTMaBr is 0.00-1.00 mkq/mL. Molar absorbtivities of complexes are 45,000, 57,000, 59,000 and 60,000, respectively. The effect of interfering ions and masking agents has been learned. Stability constants of complexes have been determined： lgKl = 7.21 ＋ 0.06 （Ge-R）,＇ lgK1 = 12.08 _＋ 0.05 （Ge-R-CPCI）, lgK1 = 12.12 ＋ 0.07 （Ge-R-CPBr） and lgK1 = 12.85 ＋ 0.06 （Ge-R-CTMaBr）. It is developed highly selective method of photometric determination of trace amounts of Ge（IV） in petroleum coke.展开更多
The formation of brominated trihalomethanes (THMs-Br) which is proved more carcinogenic than their chlorinated analogues reported was very different at various water qualities.This study was performed to assess the ef...The formation of brominated trihalomethanes (THMs-Br) which is proved more carcinogenic than their chlorinated analogues reported was very different at various water qualities.This study was performed to assess the effects of water quality parameters (bromide concentration,pH value and ammonia concentration),chlorination conditions (chlorine dose,reaction time) and ratios of Br-/DOC and Br-/Cl2 consumption on the formation and distribution of THMs-Br in chlorination.The results showed good correlation between the bromine incorporation factor (BIF) n(Br) and Br-/Cl2 consumption ratio.The formation of total THM (TTHM) was found to decrease with increasing ammonia concentration but to increase with bromide concentration and pH value.The n(Br) trends were significantly affected by the presence of bromide concentration.The effects on the molar yields of THMs were more strongly influenced by bromide concentration and dissolved organic carbon (DOC) concentration than pH value and natural organic matter (NOM) source.High Br-/DOC and Br-/Cl2 favor the formation of THMs-Br over chlorinated THMs (THMs-Cl).The experimental data including the main parameters such as bromide,DOC,ammonia,pH and reaction time were used for developing the predictive model for THMs-Br.展开更多
文摘建立液液萃取气相色谱法测定饮用水中二氯一溴甲烷和一氯二溴甲烷的方法。在200 m L水样中加入26g硫酸钠,以正己烷为萃取剂,用DB–5毛细管柱进行分离,以电子捕获检测器进行检测。二氯一溴甲烷和一氯二溴甲的质量浓度在0~50μg/L范围内与色谱峰面积均呈良好的线性,线性相关系数大于0.999,检出限均为0.01μg/L。水样加标回收率在92.4%~102.5%之间,测定结果的相对标准偏差均小于3%(n=7)。该方法操作简便,灵敏度高,适用于生活饮用水中二氯一溴甲烷和一氯二溴甲烷的测定。
文摘在 F22热溴化反应中,氯的存在有利于产物二氟氯溴甲烷(简称1211)的生成。1971年德国 Pauchsch Heinrich 等人也作了类似的报导。1978年还发现,随着反应管径的增大,通入氯的效果更加明显。促使把它作为1211生产的一项放大技术加以进一步的研究,并对其加速生成1211的反应机理作了探讨。
文摘It is investigated the interaction of Ge（IV） with bis（2,3,4-trigodroksifenolazo） benzidine （R） in the presence of KSAS （cationic surface active substances）-CPCl （cetylpyridinium chloride）, CPBr （cetylpyridinium bromide） and CTMABr （cetyltrimethylammonium bromide）. It is studied the effect pH, time on the formation of ternary complexes. It is determinated of molar absorption coefficients and stability constants of germanium. Binary （Ge-R） and triple （Ge-R-CPCI, Ge-R-CPBr, Ge-R-CTMaBr） complex form at pH 4 and pH 1, respectively. The composition proportion of binar system is 1：2 and the composition proportion triple complex is 1：1：2. The concentration interval of germanium which obeying beer low in the Ge-R 0.12-2.92 mkq/mL, in the Ge-R-CPCI is 0.04-1.46 mkq/mL, in the Ge-R-CPBr is 0.00-1.00 mkq/mL and in the Ge-R-CTMaBr is 0.00-1.00 mkq/mL. Molar absorbtivities of complexes are 45,000, 57,000, 59,000 and 60,000, respectively. The effect of interfering ions and masking agents has been learned. Stability constants of complexes have been determined： lgKl = 7.21 ＋ 0.06 （Ge-R）,＇ lgK1 = 12.08 _＋ 0.05 （Ge-R-CPCI）, lgK1 = 12.12 ＋ 0.07 （Ge-R-CPBr） and lgK1 = 12.85 ＋ 0.06 （Ge-R-CTMaBr）. It is developed highly selective method of photometric determination of trace amounts of Ge（IV） in petroleum coke.
基金Project supported by the National Hi-Tech Research and Development Program (863) of China (No.2006AA06Z311)the National Natural Science Foundation of China (No.50808052)
文摘The formation of brominated trihalomethanes (THMs-Br) which is proved more carcinogenic than their chlorinated analogues reported was very different at various water qualities.This study was performed to assess the effects of water quality parameters (bromide concentration,pH value and ammonia concentration),chlorination conditions (chlorine dose,reaction time) and ratios of Br-/DOC and Br-/Cl2 consumption on the formation and distribution of THMs-Br in chlorination.The results showed good correlation between the bromine incorporation factor (BIF) n(Br) and Br-/Cl2 consumption ratio.The formation of total THM (TTHM) was found to decrease with increasing ammonia concentration but to increase with bromide concentration and pH value.The n(Br) trends were significantly affected by the presence of bromide concentration.The effects on the molar yields of THMs were more strongly influenced by bromide concentration and dissolved organic carbon (DOC) concentration than pH value and natural organic matter (NOM) source.High Br-/DOC and Br-/Cl2 favor the formation of THMs-Br over chlorinated THMs (THMs-Cl).The experimental data including the main parameters such as bromide,DOC,ammonia,pH and reaction time were used for developing the predictive model for THMs-Br.
