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环境水样中百菌清残留的单滴微萃取-反相液相色谱测定 总被引:6,自引:1,他引:6
应用单滴微萃取(SDME)-反相液相色谱(RPLC)检测了环境水样中的百菌清残留.优化了单滴微萃取条件:环己烷萃取剂6 μL、单滴体积2 μL、搅拌速率350 r/min、萃取时间40 min、水溶液温度35 ℃、无盐度.水样经单滴微萃取后,使用Hypersil C18柱反相液相色谱分离测定百菌清.反相液相色谱条件:100%甲醇流动相、流速1.0 mL/min、柱温25 ℃、224 nm检测.方法的线性范围、检出限、相对标准偏差和富集倍数分别为1.0 ~50 μg/L、0.02 μg/L、6.1%和427倍.采用该法对环境水样中的百菌清残留进行了测定,环境水样的加标回收率为98% ~106%. 相似文献
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分散液相微萃取-气相色谱联用测定葡萄中百菌清、克菌丹和灭菌丹残留 总被引:8,自引:0,他引:8
采用分散液相微萃取与气相色谱-电子捕获检测联用技术建立了测定葡萄样品中百菌清、克菌丹和灭菌丹农药残留的新方法.对影响萃取和富集效率的因素进行了优化.萃取条件选定为在10 mL带塞离心试管中加入 5.0 mL葡萄样品溶液,并加入1.0 mL丙酮(分散剂),振荡摇匀后以5000 r/min离心5 min,然后将上层清液转移至另一离心试管中,加10.0 μL氯苯(萃取剂),分散混匀后再以5000 r/min离心5 min,萃取剂氯苯相沉积到试管底部,吸取1.0 μL萃取相直接进样分析.在优化的实验条件下,3种杀菌剂的富集倍数可达788~876倍;检出限在6.0~8.0 μg/kg(S/N=3∶ 1)范围内.以α-六六六为内标,测定3种杀菌剂的线性范围为10~150 μg/kg,线性相关系数在0.9990~0.9995范围内.本方法已成功应用于葡萄样品中百菌清、克菌丹和灭菌丹残留的测定,平均加标回收率在92.3%~106.1%范围内;相对标准偏差在4.5%~7.2%之间,结果令人满意. 相似文献
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In response to increasing scientific evidence on the toxicity and occurrence of organotin residues from antifouling paints in the aquatic environment, the use of triorganotin antifouling products was banned on boats of less than 25 m length in many countries during 1987. The use of tributyltin (TBT) products on small boats was superseded by products based on copper, containing organic booster biocides to improve the efficacy of the formulation. Available information and evidence on the occurrence, fate and toxicity of these biocides is reviewed. It is concluded that increased copper concentrations in the aquatic environment, due to the increased use of copper‐based antifoulants, do not have significant effects on marine ecosystems. However, lack of validated analytical methods, limited monitoring data, and very little information about the fate and toxicity of the booster biocides in the aquatic environment, make accurate risk assessments in relation to these compounds difficult. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
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Holger HrennWolfgang Schwack Werner SeilmeierHerbert Wieser 《Tetrahedron letters》2003,44(9):1911-1913
A strategy for the synthesis of model conjugates resembling protein-bound pesticide residues was developed on the instance of the fungicide chlorothalonil. Starting from a synthetic dodecapeptide with Fmoc and ivDde protecting groups, a multistep procedure was established for the synthesis of a defined structure. 相似文献
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Md. Musfiqur Rahman Jong‐Hyouk Park A. M. Abd El‐Aty Jeong‐Heui Choi Hey Ree Bae Angel Yang Ki Hun Park Jae‐Han Shim 《Biomedical chromatography : BMC》2013,27(4):416-421
A single extraction method was developed for chlorothalonil in shallot using gas chromatography with an electron capture detector (GC‐μECD). Samples were extracted with single‐step modified quick, easy, cheap, effective, rugged, and safe (QuEChERS) method using ethyl acetate as an extraction solvent. Significant matrix effects were observed, and the calibration curve was constructed from the matrix. The linearity of the analytical response across the studied range of concentrations (0.01–1.00 mg/L) was excellent, obtaining a correlation coefficient (r2) of 0.996. >0.996. Recovery studies were carried out on spiked shallot blank samples, at two concentration levels (0.4 and 2.0 mg/kg) with three replicates performed at each level. Mean recoveries of 97.2–104.9% with RSDs of 1.3–2.7% were obtained. The method is demonstrated to be suitable for the determination of chlorothalonil in shallot. The dissipation rates of chlorothalonil were described using first‐order kinetics, and its half‐life was 2.8 days. Based on the dissipation pattern of the pesticide residues, the pre‐harvest residue limit (PHRL) was also calculated. Residues were confirmed via mass spectrometry. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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JunLIN ShengJiaoYAN DeShouMAO RongXU LiJuanYANG FuChuLIU 《中国化学快报》2003,14(12):1219-1222
Twenty-six novel benzoylphenylurea chitin inhibitor derivatives have been synthesized in over 30~50% yield from chlorothalonil 1 via sequential fluorine exchange, aminolysis,hydrolysis, decarboxylation and acylation reactions. 相似文献
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Omar Id El Mouden Rachid Salghi Angel Ríos Abdelkhaleq Chakir Mariam El Rachidi 《International journal of environmental analytical chemistry》2013,93(5):499-510
Residue levels of azoxystrobin and chlorothalonil were determined in peppers grown in an experimental greenhouse. These two pesticides were selected on the basis of previous excesses of 26 and 24%, respectively, found in peppers samples cultivated in 2008 in eastern Morocco. The measurements were made over a 7 week period in which up to three successive treatments with azoxystrobin and a 4 week period in which up to three successive treatments with chlorothalonil were carried out. In all cases, plants were sprayed separately with azoxystrobin and chlorothalonil with application rates of active ingredients of 50 and 200?cc?hl?1, respectively. Sampling was carried out at 0, 2, 4, 7, 12, 15 and 22 days for azoxystrobin and 0, 1, 3, 7, 8 and 10 days for chlorothalonil. Residue levels of azoxystrobin and chlorothalonil were determined by liquid–liquid extraction (LLE) and gas chromatography with electron-capture detector (GC-ECD). During the study, residue levels in the plantation ranged between 1.14 and 0.02?mg?kg?1 for azoxystrobin and between 0.55 and 0.04?mg?kg?1 for chlorothalonil. The application of an intensive washing process to the pepper samples did not lead to a significant reduction in the residue levels of either pesticide. Likewise, significant differences were not found between the residue levels in the ‘edible’ and ‘inedible’ parts of the peppers. 相似文献
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