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用气相色谱法定量测定了家用气雾杀虫剂中的丙烯菊酯、氯菊酯和增效醚。色谱柱为5%QF-1/Chro-mosorbWHP,以邻苯二甲酸二苯酯为内标物,测得的回收率分别为100%,102%,99.9%;变异系数为0.13,0.56,0.48,方法简便、快速、准确。 相似文献
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A nonmagnetically modified graphene was employed as the adsorbent in the dispersive solid-phase extraction (d-SPE) for the isolation of permethrin from urine samples that were further analyzed by the HPLC/UV method. The following four key factors influencing permethrin extraction efficacy were studied: 1. graphene suspension volume, 2. adsorption time, 3. desorbent (acetonitrile) volume, and 4. desorption time. Under the optimized conditions of the d-SPE (graphene) procedure the main validation parameters of the analytical method were determined as follows: extraction recovery (%) 71.2, 63.5, and 95.4; intra-day repeatability (%RSD) 14.7, 11.5, and 15.2; inter-day repeatability (%RSD) 16.2, 11.9, and 19.1 for 0.125, 0.250, and 1.0 µg/mL permethrin concentration levels, respectively. Limits of detection (LOD) and quantification (LOQ) were 0.045 and 0.125 µg mL?1, respectively. The proposed method may be useful for the monitoring of permethrin in human urine taken from people dressed in uniforms disinfected with this pesticide. 相似文献
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采用FS920稳态荧光光谱仪对绿茶和铁观音这两种不同品种茶叶的氯菊酯溶液的荧光光谱特性进行了分析,发现这两种茶叶的荧光峰均位于λ_(ex)/λ_(em)=(390~410)/675 nm,氯菊酯的荧光峰λ_(ex)/λ_(em)=300/330nm。为了准确测定这两种茶叶中氯菊酯农药残留的含量,采用遗传算法优化的径向基函数神经网络对其进行了分析,当训练到74次时,均方差精度达到10~(-3),绿茶、铁观音的氯菊酯溶液预测样本的平均回收率分别为99.35%和98.89%,平均相对标准偏差分别为1.25%和1.21%。与建立的径向基函数神经网络模型进行了对比,结果表明三维荧光分析技术与遗传算法优化的径向基函数神经网络相结合能够较好地检测出茶叶中氯菊酯农药残留的含量,检测灵敏度大大提高,检出限范围广,可达0.004 8~24 mg/kg,远低于欧盟规定的茶叶中氯菊酯最高残留限量0.1 mg/kg,为检测农药残留提供了一种快速简便的新方法。 相似文献
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Tayebeh Asadi Nader Rahimi Kakavandi Amir Nili Ahmadabadi Ali Heshmati Akram Ranjbar Khosrou Abdi Maryam Ezoddin 《Biomedical chromatography : BMC》2022,36(5):e5304
An effervescent tablet-assisted switchable polarity solvent–based homogeneous liquid-phase microextraction combined with gas chromatography with flame ionization detection has been conducted for the separation, preconcentration, and detection of permethrin and deltamethrin in the river water specimens. Triethylamine (TEA) was utilized as the switchable polarity solvent in this method. The switching process was carried out by the dissolution of an effervescent tablet including an effervescency agent (sodium carbonate) and a proton donor agent (citric acid). Changing the pH of the specimen solution enhanced the conversion of TEA into protonated triethylamine carbonate through the tablet that generated carbon dioxide bubbles in situ. Finally, the addition of sodium hydroxide changed the ionization state of TEA and separated the two phases. Influential factors in the extraction were investigated. According to optimal situations, the limit of detection and the limit of quantification were 0.16 and 0.5 μg L−1 for permethrin and 0.03 and 0.1 μg L−1 for deltamethrin, respectively. The preconcentration factor was 194 in river water samples and inter- and intra-day precision (relative standard deviation %; n = 5) was <5%. The extraction recovery was obtained in the range of 93.0%–97% for permethrin and deltamethrin in water samples. 相似文献
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取代苯甲醛肟羧酸酯的合成及生物活性研究:I.取代苯甲醛肟二氯菊酸酯 … 总被引:8,自引:1,他引:8
探讨了α-取代苯甲醛肟合成的新方法,合成了20种新型菊酸肟酯类化合物,并对其进行了初步生物活性测试,化合物5a,5f具有很好的抗病毒活性。 相似文献
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Adair Divino da Silva Badaro Rmulo Sousa Muhammad Naeem Maxwell Santana Librio Rayane Saory Medeiros dos Santos Flaviane camara de Souza Thrcio Costa Michele Feitor Javed Iqbal 《先进技术聚合物》2020,31(10):2229-2238
The mosquito‐transmitted diseases are of serious concern and are affecting several millions of peoples worldwide. Instead of medication afterward the disease initiated, self‐protection against the mosquito's is preferable, specifically in endemic areas. For this purpose, the permethrin coated clothing is a suitable choice to avoid mosquitos' bites. Unfortunately, the permethrin coating on fabrics is not long‐lasting, and its laundering resistance is very low on hydrophobic fabric. In this study, the effect of plasma surface modification of PET fabric on the adhesion of permethrin and its laundering resistance are evaluated. The plasma processing is carried out in nitrogen, oxygen, and nitrogen–oxygen mixture plasma. The samples are analyzed using Fourier Transform Infrared spectroscopy, X‐ray photoelectron spectroscopy, scanning electron microscope and chromatography. The results show that the oxygen plasma pre‐treated samples exhibit the higher residual contents of permethrin after 60 wash cycles as compared with other gasses. Without plasma pre‐treatment, the 95% loss, whereas the sample with oxygen plasma pre‐treatment shows that only 22% loss of initial concentration of permethrin occurs after washing. This study shows that plasma pre‐treatment is valuable to improve the absorption of permethrin in PET and its laundering‐resistance. As plasma treatment is a cost‐effective technique, it needs less processing time and eco‐friendly, thus it is a great choice to deposit long‐lasting permethrin coating by plasma pre‐treatment, instead of conventional binding agents. Remarkably, the plasma treatment technique is a well‐established and industrially acceptable technique, thus expected to be of noteworthy importance for insecticide garments manufacturers. 相似文献
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A. Martín-Esteban P. Fernández C. Cámara G. N. Kramer E. A. Maier 《International journal of environmental analytical chemistry》2013,93(1-4):125-141
Abstract An interlaboratory exercise was carried out to improve the state of the art of some polar pesticide determination in water (atrazine, simazine, carbaryl, propanil, linuron, fenamiphos and permethrin). The preparation, the homogeneity and the stability of freeze-dried water samples containing the above pesticides was studied. The final concentration of each pesticide in water was in the 50–80 μg.?1 range with a salt content of 2.5 g.l?1 of NaCl. After the lyophilization the residue was reho-mogenised, filled into amber glass bottles and stored at -20 °C and +20 °C. Every three months, one sample was analysed to verify the stability of the residue. All pesticides were determined by high performance liquid chromatography with diode-array detection (HPLC-DAD) except permethrin which was determined by gas chromatography with electron capture detection (GC-ECD). The results obtained show that the atrazine, carbaryl, propanil, linuron and fenamiphos samples were homogeneously distributed, whereas simazine and permethrin were not. With respect to the stability over three months, all pesticides were stable at ?20 °C. Atrazine, simazine, carbaryl, propanil and linuron are also stable for the maximum storage time at +20 °C but the concentration of fenamiphos decreased by about 70% after one month. The results obtained in the interlaboratory study by the participants were in good agreement for many of the pesticides. 相似文献