建立固相萃取-液相色谱-串联质谱法测定地下水中44种抗生素。调节样品pH值为3,加入质量浓度为0.5 g/L Na_(2)EDTA,用5 mL 0.1%甲酸-甲醇和3 mL 5%氨水-甲醇以流速为2 mL/min洗脱,动态多反应监测分析。结果表明,44种抗生素在质量浓度为0...建立固相萃取-液相色谱-串联质谱法测定地下水中44种抗生素。调节样品pH值为3,加入质量浓度为0.5 g/L Na_(2)EDTA,用5 mL 0.1%甲酸-甲醇和3 mL 5%氨水-甲醇以流速为2 mL/min洗脱,动态多反应监测分析。结果表明,44种抗生素在质量浓度为0~50μg/L时,线性相关系数大于0.990,方法检出限为0.05~0.90 ng/L,加标回收率为39.1%~143%,RSD为1.9%~14%。采用该方法测定苏北某地地下水,检出18种抗生素(质量浓度为ND~21.7 ng/L)。展开更多
The technological process of preparation of colloid Sb 2O 5 by oxidation of Sb 2O 3 with hydrogen peroxide using borax as a stabilizer has been investigated. The optimum preparation conditions selected by orthogonal f...The technological process of preparation of colloid Sb 2O 5 by oxidation of Sb 2O 3 with hydrogen peroxide using borax as a stabilizer has been investigated. The optimum preparation conditions selected by orthogonal factorization method as follows m (H 2 O)∶ m (Sb 2 O 3 )=7 5∶1, n (H 2 O 2 )∶ n (Sb 2 O 3 )=3∶1, m (Na 2 B 4 O 7 ·10H 2 O)∶ m (Sb 2 O 3 )=1∶10, 95 ℃, 1 5 h. The conversion of Sb 2 O 3 >95%, light transmittance of colloid >85% and the average diameter of Sb 2 O 5 particles was 50 nm. The colloid Sb 2 O 5 prepared was storage stable without coagulation for more than one year.展开更多
文摘建立固相萃取-液相色谱-串联质谱法测定地下水中44种抗生素。调节样品pH值为3,加入质量浓度为0.5 g/L Na_(2)EDTA,用5 mL 0.1%甲酸-甲醇和3 mL 5%氨水-甲醇以流速为2 mL/min洗脱,动态多反应监测分析。结果表明,44种抗生素在质量浓度为0~50μg/L时,线性相关系数大于0.990,方法检出限为0.05~0.90 ng/L,加标回收率为39.1%~143%,RSD为1.9%~14%。采用该方法测定苏北某地地下水,检出18种抗生素(质量浓度为ND~21.7 ng/L)。
文摘The technological process of preparation of colloid Sb 2O 5 by oxidation of Sb 2O 3 with hydrogen peroxide using borax as a stabilizer has been investigated. The optimum preparation conditions selected by orthogonal factorization method as follows m (H 2 O)∶ m (Sb 2 O 3 )=7 5∶1, n (H 2 O 2 )∶ n (Sb 2 O 3 )=3∶1, m (Na 2 B 4 O 7 ·10H 2 O)∶ m (Sb 2 O 3 )=1∶10, 95 ℃, 1 5 h. The conversion of Sb 2 O 3 >95%, light transmittance of colloid >85% and the average diameter of Sb 2 O 5 particles was 50 nm. The colloid Sb 2 O 5 prepared was storage stable without coagulation for more than one year.