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乙醇-正丙醇-磷酸二氢钠多元混合双水相体系萃取/检测湖水中的诺氟沙星残留
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作者 郭东刚 倪良 王良 《应用化学》 CAS CSCD 北大核心 2021年第7期847-856,共10页
构建了乙醇-正丙醇-磷酸二氢钠(NaH_(2)PO_(4))多元混合双水相体系萃取/检测环境水样中的诺氟沙星,讨论了醇的用量、盐的种类及浓度、pH值、温度对诺氟沙星分配行为的影响,并采用响应曲面法(Response surface methodology,RSM)对实验条... 构建了乙醇-正丙醇-磷酸二氢钠(NaH_(2)PO_(4))多元混合双水相体系萃取/检测环境水样中的诺氟沙星,讨论了醇的用量、盐的种类及浓度、pH值、温度对诺氟沙星分配行为的影响,并采用响应曲面法(Response surface methodology,RSM)对实验条件进行优化。结果表明,在乙醇与正丙醇加入量为4 mL(体积比为1∶1),NaH_(2)PO_(4)的浓度为0.200 g/mL,温度为30℃,pH=5的最优条件下,诺氟沙星的萃取率为94.34%。该多元双水相体系较单元双水相体系相比,目标物的萃取率明显提升。 展开更多
关键词 多元混合双水相 小分子醇 萃取/检测 诺氟沙星
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Determination of Eleutheroside B and E in Acanthopanax Preparations by High-P erformance Liquid Chromatography with Solid-Phase Extraction 被引量:6
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作者 胡芳弟 封士兰 +2 位作者 赵健雄 陈立仁 徐静汶 《Journal of Chinese Pharmaceutical Sciences》 CAS 2005年第1期51-55,共5页
Aim An HPLC method for analyzing eleutheroside B (ELU B) and eleutheroside E(ELU E) , two of the main active substances of Acanthopanax preparations were studied. Methods Thesamples were analyzed on a kromasil ODS col... Aim An HPLC method for analyzing eleutheroside B (ELU B) and eleutheroside E(ELU E) , two of the main active substances of Acanthopanax preparations were studied. Methods Thesamples were analyzed on a kromasil ODS column with water-acetonitrile as a gradient mobile phase.The flow rate was 0.8 mL·min^(-1) and detecting wavelengths were 206 nm for ELU B, 220 nm for ELUE, solid phase extraction (SPE) and internal standard-salicin were selected. Results The recoveriesof Acanthopanax tablets and injection were 90.4% - 96.8% and 96.4% - 99.8% for ELU B, 87.7% -93.3%and 95.7% - 98.5% for ELU E, respectively. The linear ranges were 4.45 - 22.25 μg· mL^(-1) (r =0.999 8) and 5.11 - 25.55 μg·mL^(-1) ( r = 0.999 7) respectively. Conclusion This method can savethe time for cleaning the chromatographic system and improve sensitivity for Acanthopanaxpreparations , thus providing a way to evaluate the quality of Acanthopanax preparations. 展开更多
关键词 eleutherosides acanthopanax preparations HPLC solid phase extraction
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Determination of Iprobenfos Residue in Rice by GC-FTD using Two-dim Ensional Purification
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作者 万宇 张晓波 +1 位作者 王军 蒋闳 《Agricultural Science & Technology》 CAS 2015年第7期1325-1328,1331,共5页
[Objective] This study aimed to establish a determination method for iprobenfos residue in rice straw and husked rice. [Method] The rice straw and husked rice samples were extracted by acetone-ethyl acetate mixed solv... [Objective] This study aimed to establish a determination method for iprobenfos residue in rice straw and husked rice. [Method] The rice straw and husked rice samples were extracted by acetone-ethyl acetate mixed solvent. The extracts were purified using SPE C18 column and SPE NH2 column, and the iprobenfos residues were determined by GC-FTD. [Result] In the concentration range of 0.005-5.0 mg/kg, iprobenfos concentration showed a good linear relationship with peak area (r=0.999 8). When the iprobenfos concentrations were 0.01, 0.1 and 1.0 mg/kg respectively, the recoveries of added iprobenfos from rice straw ranged from 72.6% to 99.7% with relative standard deviation ranging from 5.65% to 8.48%; the recoveries of added iprobenfos from husked rice ranged from 81.6% to 97.6% with relative standard deviation ranging from 3.74% to 7.63%. The minimum detectable quantity of iprobenfos was 5×10^-12 g, and the minimum detectable concentrations of iprobenfos in rice straw and husked rice samples were 2.0 and 0.5 μg/kg, respec- tively. [Conclusion] The established determination method is characterized by low de- termination limit, high sensitivity, good reproducibility and high operability, which all meet the requirements by Guideline on Pesticide Residue Trials of the Ministry of Agriculture. 展开更多
关键词 Iprobenfos RICE Solid phase extraction Two-dimensional purification FTD
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Butyltin compounds in vinegar collected in Beijing:Species distribution and source investigation
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作者 CUI ZongYan ZHANG KeGang +2 位作者 ZHOU QunFang LIU JiYan JIANG GuiBin 《Science China Chemistry》 SCIE EI CAS 2012年第2期323-328,共6页
Forty-eight vinegar samples including white vinegar, rice vinegar and mature vinegar were collected from several markets in Beijing. Butyltin compounds were determined by headspace solid-phase microextraction coupled ... Forty-eight vinegar samples including white vinegar, rice vinegar and mature vinegar were collected from several markets in Beijing. Butyltin compounds were determined by headspace solid-phase microextraction coupled with gas chromatography and flame photometric detector after in situ ethylation with sodium tetraethylborate. Butyltin species were detected in sixteen vinegar samples and ranged from 0.012 to 14.10 lag Sn L 1. The detection rate of white vinegar is higher than that of rice vinegar and mature vinegar. Vinegar samples with relatively high butyltin concentration (〉1.5 μg Sn L-1) were those stored in plastic bags, indicating that the plastic bag was one of the possible sources of butyltin contamination. This was further confirmed by the leaching experiments of three selected plastic bags, and monobutyltin was detected in the leaching solvents. According to the estimation, the average daily intake of total butyltin compounds through vinegar consumption is about 0.04 ng Sn/kg b.w., much lower than the Tolerable Daily Intake (TDI) of 100 ng Sn/kg b.w. set by the European Food Safety Authority (EFSA). 展开更多
关键词 butyltin compounds VINEGAR headspace solid-phase microextraction gas chromatography-flame photometric detection
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