目的建立高效液相色谱法测定达格列净起始物料5-溴-2-氯-4′-乙氧基二苯甲烷中的有关物质,并通过杂质对照品定位验证该方法可有效检出5-溴-2-氯-4′-乙氧基二苯甲烷中的有关物质。方法采用苯基键和硅胶色谱柱(Kinet ex Biphenyl,250...目的建立高效液相色谱法测定达格列净起始物料5-溴-2-氯-4′-乙氧基二苯甲烷中的有关物质,并通过杂质对照品定位验证该方法可有效检出5-溴-2-氯-4′-乙氧基二苯甲烷中的有关物质。方法采用苯基键和硅胶色谱柱(Kinet ex Biphenyl,250×4.6 mm,5μm);流动相A为0.05%的磷酸水溶液,流动相B为乙腈-甲醇(50∶50);柱温为40℃;检测波长为220 nm;流速为1.0 mL·min^(-1)。结果5-溴-2-氯-4′-乙氧基二苯甲烷及各杂质在各自浓度范围内,溶液浓度和峰面积呈良好的线性关系(r≥0.9996);平均回收率在95.0%~105.0%范围内,RSD(n=9)<2.0%;系统适用性溶液中,杂质SM1-8、主峰和杂质SM1-2依次出峰,分离度均大于1.5。结论该方法灵敏度高、专属性强、准确度高,适用于起始物料5-溴-2-氯-4′-乙氧基二苯甲烷有关物质的检测。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 photodissociation/photoionization processes of chlorobromomethane (CH_2BrCl) induced by fem- tosecond laser pulses have been investigated using pump-probe scheme combined with the time-of-flight mass spectra. The ...The photodissociation/photoionization processes of chlorobromomethane (CH_2BrCl) induced by fem- tosecond laser pulses have been investigated using pump-probe scheme combined with the time-of-flight mass spectra. The dominate photoproducts are observed at different delay time of the pump (400 nm) and probe (800 nm) pulses and the corresponding time-dependence of them is obtained. The results show that the decaying time of the molecule CH_2BrCl in the A-band is in the 100 fs. The decaying tendencies of the fragment ions (CH_2Cl^+ and CH_2Br^+) and the parent ion (CH_2BrCl^+) are almost the same and the relative ratios of the yields of them keep constant during the delay time of 0 to 150 fs. These facts suggest that the fragment ions come from the fragmentation of the parent ions in excited electronic states. The probabilities to form CH_2Cl^+ and CH_2Br^+ are obtained from the relative ratio of the ion intensity and are about 71.6% and 14.2%, respectively.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Supported by the National Natural Science Foundation of China (Grant Nos. 10534010 and 20673140)
文摘The photodissociation/photoionization processes of chlorobromomethane (CH_2BrCl) induced by fem- tosecond laser pulses have been investigated using pump-probe scheme combined with the time-of-flight mass spectra. The dominate photoproducts are observed at different delay time of the pump (400 nm) and probe (800 nm) pulses and the corresponding time-dependence of them is obtained. The results show that the decaying time of the molecule CH_2BrCl in the A-band is in the 100 fs. The decaying tendencies of the fragment ions (CH_2Cl^+ and CH_2Br^+) and the parent ion (CH_2BrCl^+) are almost the same and the relative ratios of the yields of them keep constant during the delay time of 0 to 150 fs. These facts suggest that the fragment ions come from the fragmentation of the parent ions in excited electronic states. The probabilities to form CH_2Cl^+ and CH_2Br^+ are obtained from the relative ratio of the ion intensity and are about 71.6% and 14.2%, respectively.
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.
