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141.
转Bt基因棉花抗虫萜烯类化合物时空动态的HPLC分析 总被引:14,自引:0,他引:14
利用高效液相色谱(HPLC)技术对转Bt基因棉花抗虫萜烯化合物种类、含量以及时空动态进行了初步研究。结果表明,被研究的抗虫棉品种抗虫萜烯类化合物在不同品种、不同组织器官间含量差异较大。叶片中杀实夜蛾素(包括H1、H2、H3、H4)含量较高,花及蕾中棉酚含量的比例明显高于叶片。总抗虫萜烯类(包括棉酚、半棉酚酮、杀实夜蛾素H1、H2、H3、H4以及甲氧基半棉酚酮等)均以铃、顶叶含量最高,蕾、花柱等器官次之。说明在棉花不同品种、同一品种不同器官中是不同的萜烯类化合物在起到抗虫作用。图3参16 相似文献
142.
采用高效液相色谱法测定鸡蛋清和蛋黄中磺胺嘧啶、磺胺吡啶、磺胺二甲基嘧啶、磺胺甲氧哒嗪、磺胺甲恶唑、磺胺间甲氧嘧啶、磺胺喹恶啉等7种磺胺类药物残留,优化了色谱条件和样品预处理方法。7种磺胺类药物在0.050 mg/L~10.0 mg/L范围内线性良好,检出限和定量限分别低于0.02 mg/kg和0.04 mg/kg。在0.250 mg/kg和0.500 mg/kg两个添加水平,蛋清中的回收率为81.0%~100%,RSD为0.8%~4.8%,蛋黄中的回收率为72.2%~94.1%,RSD为1.1%~6.9%。 相似文献
143.
144.
采用C18固相膜萃取对地下水中15种多环芳烃进行富集净化,以二氯甲烷作洗脱溶剂,高效液相色谱法,荧光检测器测定。对萃取、浓缩和色谱条件进行优化,在1.ooixg/L~40.0μg/L范围内测定标准系列溶液并绘制标准曲线,相关系数R2〉0.999;15种多环芳烃的仪器检出限为0.4ng/L~3.0ng/L;对地下水样品加标,平均回收率在75.7%~96.7%之间;标准溶液平行测定7次的RSD为3.1%~11.9%。 相似文献
145.
146.
以对乙酰氨基酚为目标物,利用固相萃取(SPE)-高效液相色谱(HPLC)法测定了该药物在泰安市污水处理厂进出水和地表水体中的含量。结果表明,对乙酰氨基酚在污水处理厂进水中均被检出,质量浓度为0.9~238μg/L,表明生活污水为污水处理厂该药物活性成分的来源,出水中质量浓度为ND~8.3μg/L,去除率较高,其中生物降解是主要的降解机制。在泮河中的质量浓度为ND~3.59μg/L,与国内外其他地表水体相比,处于同一个数量级,且污水厂排水口下游水体中目标物浓度高于上游,反映出污水处理厂排放可能是其受纳水体中PPCPs的主要来源之一。 相似文献
147.
148.
S. K. Sahoo G. S. Chahil Kousik Mandal R. S. Battu Balwinder Singh 《Journal of environmental science and health. Part. B》2013,48(1):42-50
Dissipation of β-cyfluthrin and imidacloprid in okra was studied following three applications of a combination formulation of Solomon 300 OD (β-cyfluthrin 9 % + imidacloprid 21 %) @ 60 and 120 g a.i. ha?1 at 7 days interval. Residues of β-cyfluthrin and imidacloprid in okra were estimated by gas liquid chromatography (GLC) and high performance liquid chromatography (HPLC), respectively. Residues of β-cyfluthrin were confirmed by gas chromatograph–mass spectrometry (GC-MS) and that of imidacloprid by high performance thin layer chromatography (HPTLC). Half-life periods for β-cyfluthrin were found to be 0.91 and 0.68 days whereas for imidacloprid these values were observed to be 0.85 and 0.96 days at single and double the application rates, respectively. Residues of β-cyfluthrin dissipated below its limit of quantification (LOQ) of 0.01 mg kg?1 after 3 and 5 days at single and double the application dosage, respectively. Similarly, residues of imidacloprid took 5 and 7 days to reach LOQ of 0.01 mg kg?1, at single and double dosages respectively. Soil samples collected after 15 days of the last application did not show the presence of β-cyfluthrin and imidacloprid at their detection limit of 0.01 mg kg?1. 相似文献
149.
Ji Y. Hu Bi Z. Dong Zi H. Zhen 《Journal of environmental science and health. Part. B》2013,48(5):385-389
A simple and efficient residue analysis method for direct determination of ioxynil octanoate in maize and soil was developed and validated with High Performance Liquid Chromatography-Ultra Violet (HPLC-UV). The samples were extracted with mixtures of acetonitrile and deionized water followed by Solid Phase Extraction (SPE) to remove co-extractives prior to analysis by HPLC-UV. The recoveries of ioxynil octanoate extracted from maize and soil samples ranged from 86 %–104 % and 84 %–96 %, respectively, with relative standard deviation (RSD) less than 7.84% and sensitivity of 0.01 mg kg?1. The method was applied to determine the residue of ioxynil octanoate in maize and soil samples from experimental field. Data had shown that the dissipation rate in soil was described as pseudo-first-order kinetics and the half-life (t1/2) was less than 1.78 days. No ioxynil octanoate residue (<0.01 mg kg?1) was detected in maize at harvest time withholding period of 60 days after treatments of the pesticide. Direct confirmation of the analytes in field trial samples was realized by Liquid Chromatography-Mass Spectrometry (LC-MS). 相似文献
150.
Shashi B. Singh Tapas K. Das Gita Kulshrestha 《Journal of environmental science and health. Part. B》2013,48(5):324-330
The persistence of fenoxaprop ethyl {Ethyl (RS)-2-[4-(6-chloro-1,3-benzoxazol-2-yloxy) phenoxy] propionate} herbicide and its active metabolite fenoxaprop acid was investigated in soil and wheat crop. Fenoxaprop acid was prepared by alkaline hydrolysis of fenoxaprop ethyl. A HPLC method was developed in which fenoxaprop ethyl herbicide and its acid metabolite showed sharp single peak at 6.44 and 2.61 min respectively. The sensitivity of the method for ester and acid was 2 and 1 ng respectively with limit of detection of 0.1 and 0.05 μg mL?1. The recovery of fenoxaprop ethyl and fenoxaprop acid from soil, wheat straw and grain ranged between 73.8–80.2%. In a field experiment fenoxaprop ethyl (Puma super® 10 EC) when applied to wheat crop at the rate of 120 g and 240 g a.i. ha-1 as post emergence spray, fenoxaprop ethyl converted to fenoxaprop acid. Residues of fenoxaprop ethyl and acid dissipated in soil with a half-life of 0.5 and 7.3 days, respectively. At harvest no detectable residues of fenoxaprop ethyl or acid were observed in soil, wheat grain and straw samples. 相似文献