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In this paper, the conversion of azoxystrobin in a strongly fluorescent degradation product by UV irradiation with quantitative purposes and its fluorimetric determination are reported for the first time. A multicommuted flow injection-solid phase spectroscopy (FI-SPS) system combined with photochemically-induced fluorescence (PIF) is developed for the determination of azoxystrobin in grapes, must and wine. Grape samples were homogenized and extracted with methanol and further cleaned-up by solid-phase extraction on C18 silica gel. Wine samples were solid-phase extracted on C18 sorbent using dichloromethane as eluent. Recoveries of azoxystrobin from spiked grapes (0.5-2.0 mg Kg−1), must (0.5-2.0 μg mL−1) and wine (0.5-2.0 μg mL−1) were 84.0-87.6%, 95.5-105.9% and 88.5-111.2%, respectively. The quantification limit for grapes was 0.021 mg Kg−1, being within European Union regulations, and 18 μg L−1 and 8 μg L−1 for must and wine, respectively. 相似文献
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Polati S Bottaro M Frascarolo P Gosetti F Gianotti V Gennaro MC 《Analytica chimica acta》2006,579(2):146-151
The paper presents a new HPLC method, with UV and MSn detection, for the determination of seven pesticides, including the sulfonylurea herbicides amidosulfuron, azimsulfuron, nicosulfuron, rimsulfuron, thifensulfuron methyl, tribenuron methyl, and the fungicide azoxystrobin characterised by a methoxyacrilate structure. The methodology consists of a preconcentration/SPE (solid phase extraction) step and HPLC-UV (240 nm detection wavelength)-MSn analysis. Under the optimised conditions and after a 1000/1 preconcentration factor, the limits of detection were lower than 14.5 ng L−1 for UV detection and lower than 8.1 ng L−1 for MS detection. The limits of quantification were lower than 48.3 ng L−1 in UV detection and than 26.9 ng L−1 in MSn detection. The analysis of two samples, spiked with a mixture of the pesticides at threshold level concentrations, gave more than 60% recovery. 相似文献
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AbstractIn this research, hydrophilic molecularly imprinted microspheres (HMIPs) for azoxystrobin were successfully synthesized through precipitation polymerization. The adsorption capacities of HMIPs for azoxystrobin in water medium were higher than ordinary molecularly imprinted microspheres (MIPs), and HMIPs exhibited good hydrophilic properties. HMIPs and non-imprinted microspheres (HNIPs) were characterized by FT-IR, SEM, laser particle size analyzer and TGA. Comparing with HNIPs, azoxystrobin had a significant influence on morphologys and sizes of HMIPs. The Langmuir adsorption isotherm illustrated each binding site of HMIPs had the same adsorption capacity. The Lagergran pseudo-second-order kinetic model indicated the adsorption process between azoxystrobin and HMIPs was chemical adsorption. BET test illustrated HMIPs had bigger specific surface areas than HNIPs. Selective adsorption indicated that HMIPs had highly specific recognition of azoxystrobin. HMIPs successfully exhibited high selectivity and high hydrophilicity in water medium. 相似文献
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气相色谱法检测西兰花和荷兰豆中嘧菌酯残留量 总被引:3,自引:1,他引:2
建立了气相色谱法检测西兰花和荷兰豆中嘧菌酯残留量的快速分析方法。样品用V(乙酸乙酯)∶V(环己烷)=1∶1超声波萃取,气相色谱-氮磷检测法测定。外标法定量,结果表明,嘧菌酯在0.01~1.0 mg/kg范围内呈线性关系,其相关系数r>0.99。在低、中、高3个添加水平,嘧菌酯的回收率为85%~110%,相对标准偏差为3.8%~11.4%,检出限为0.01 mg/kg。 相似文献
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LIU Yang LIU Ming ZHANG Dongkai HUA Xuewen WANG Baolei ZHOU Sha LI Zhengming 《高等学校化学研究》2016,32(6):952-958
A series of strobilurin-1,2,4-triazole derivatives containing a furan or thiophen ring was designed and synthesized. The structures of the compounds were characterized by 1H NMR, 13C NMR and HRMS spectra. The bi-oassays indicated that the fungicidal activities of compounds 10b(EC50=14.82 mg/L) and 10c(EC50=18.72 mg/L) against Cercospora arachidicola Hori in vitro were much higher than that of Azoxystrobin as control(EC50=40.54 mg/L) and the fungicidal activities of compounds 10u(EC50=8.66 mg/L) and 10n(EC50=9.89 mg/L) against Rhizotonia cerealis in vitro were higher than that of the same control(EC50=10.86 mg/L). Compounds 10b, 10c, 10n and 10k could be considered as the leading compounds for further investigation. 相似文献
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Chunwei Wang Yan Wang Rui Wang Jiaqi Yan Yanbin Lv Aijun Li 《International journal of environmental analytical chemistry》2017,97(1):1-13
The combinational fungicide suspension (11.7% propiconazole + 7% azoxystrobin), developed by Syngenta Co., Ltd., is very effective for the control of Alternaria black spot on ginseng. A simple and effective method was developed for determining propiconazole and azoxystrobin residues by high-performance liquid chromatography coupled with tandem mass spectrometry (HPLC-MS/MS). The recoveries of propiconazole ranged from 81.0% to 98.0% with relative standard deviations (RSDs) of 1.23–8.46%, while the recoveries of azoxystrobin ranged from 83.2% to 98.8% with RSDs of 3.29–9.50%. For the dissipation kinetics, the combinational fungicide was sprayed with dosage of 225 g a.i.ha?1 (1.5 times of recommended dosage) in ginseng and soil at two different locations. The dissipation kinetics followed the first-order kinetics with half-lives of 6.66–13.33 days for propiconazole and 4.92–9.12 days for azoxystrobin. Based on the terminal residues data, the preharvest interval (PHI) could be 35 days at recommended dosage in ginseng. The dietary exposure risk was estimated by risk quotient (RQ). The result showed that the RQ value was obviously lower than RQ = 1, indicating that spraying propiconazole and azoxystrobin in ginseng at recommended dosage was safe for human beings. 相似文献
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气相色谱法测定甜瓜和苹果中嘧菌酯残留 总被引:12,自引:0,他引:12
建立了甜瓜和苹果中嘧菌酯残留量的两种气相色谱快速分析方法。实验样品用乙酸乙酯-环己烷(50:50,V/V)超声波萃取,气相色谱-氮磷检测(NPD)或气相色谱-微池电子捕获检测(μ-ECD)法测定。因不存在干扰峰,样品不需净化。这两种检测方法互相确证了定性和定量结果,方法回收率均在85.7%~110.5%之间;最低检出浓度:苹果在NPD上为0.001mg/kg,在μ-ECD上和甜瓜在两种检测器上均为0.002mg/kg,标准曲线的线性回归系数分别为0.9991(μ-ECD)和0.9998(NPD)。经配对t检验统计分析,两种检测方法定量结果无显著性差异。 相似文献
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本文建立了铁皮石斛、浙贝母和人参三种中药材中嘧菌酯的残留检测方法。样品采用乙腈提取,二氯甲烷液-液萃取,弗罗里硅土-中性氧化铝-活性炭柱层析净化,乙酸乙酯定容,气相色谱-电子捕获检测器(GC-ECD)检测,基质外标法定量。结果表明:在0.01~1.0mg/L范围内,不同基质中嘧菌酯的峰面积与其质量浓度间呈良好线性关系,相关系数均大于0.999;在0.01、0.1和0.5mg/kg的添加水平下,嘧菌酯在3种中药材基质中的平均回收率为85.0%~94.9%,日内相对标准偏差(RSD)均小于5.2%(n=5),日间RSD均小于6.7%(n=15);其在铁皮石斛、浙贝母和人参基质中的检出限(LOD)为0.002~0.004mg/kg,定量限(LOQ)均为0.01mg/kg。方法的准确度和精密度均满足残留分析要求,适用于铁皮石斛、浙贝母和人参中嘧菌酯的检测。 相似文献
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