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91.
高效液相色谱法同时测定大豆中10种磺酰脲类除草剂的残留量 总被引:13,自引:0,他引:13
首次建立了同时检测大豆中10种磺酰脲类除草剂(环氧嘧磺隆、噻吩磺隆、甲磺隆、醚苯磺隆、氯磺隆、苄嘧磺隆、氟磺隆、吡嘧磺隆、氯嘧磺隆和氟嘧磺隆)多残留量的反相高效液相色谱(RP-HPLC)方法。样品经乙腈提取、正己烷液-液分配、Florisil填充柱净化后,采用RP-HPLC-二极管阵列检测器检测(DAD)法测定,外标法定量。对样品前处理和色谱分离条件进行了详细的研究和优化。10种磺酰脲类除草剂的质量浓度在0.1~10.0 mg/L范围内其浓度与峰面积的线性关系良好,相关系数为0.9996~0.9997;在 相似文献
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93.
高效液相色谱法分析快杀稗 总被引:4,自引:0,他引:4
In this paper,determination of quinclorac by reversedphase high performance liquid chromatographicmethod,using a Shim-Pack CLC-CN column and methanol-water(containing 0.5%CH_3COOH)(30:70)asmobile phase has been described,The method proved to be accurate and good in linear correlation. 相似文献
94.
超高效液相色谱-电喷雾串联质谱法同时测定大豆中107种除草剂残留 总被引:7,自引:1,他引:7
采用超高效液相色谱-电喷雾串联四极杆质谱仪(UPLC-ESI-MS-MS),在多反应监测(MRM)模式下建立了测定大豆中107种除草剂残留的定性定量分析方法。方法中的除草剂,覆盖了日本"肯定列表"中规定的大部分除草剂。样品分别用乙腈和V(乙腈)∶V(50mmol/LHCl)=7∶3混合液各提取一次,合并提取液,并与N-丙基乙二胺(PSA)混合去除色素,然后通过冷冻离心去除脂肪,再经过500mgC18小柱进一步净化,得到样品溶液。使用ACQuityUPLCTMBEHC18反相柱,流动相为0.2%甲酸溶液和乙腈,在梯度条件下分析;目标分析物使用超高效液相色谱-电喷雾串联质谱进行测定;以保留时间和离子对(母离子和一个碎片离子)信息比较进行定性和定量。该法的定量限为0.1~50μg/kg。添加水平在0.05~2μg/kg范围内,多数除草剂的加标回收率为58%~130%,相对标准偏差为4.3%~23%。本方法简便、有效、灵敏。适合大豆中残留的多种除草剂筛查检测的需要。 相似文献
95.
首次合成了二茂铁基-1,3,4-三唑Schiff碱衍生物(5a~5e),利用IR、1H NMR和HRMS等手段对其进行了结构表征。 用黄瓜子叶生根法以及小麦芽鞘法,分别测试化合物的细胞分裂素活性和生长素活性。 结果表明,在10 mg/L浓度下,有4个化合物的子叶生根促进作用为46.9%~73.6%,比对参照物的细胞分裂活性更高,但生长素活性不明显,化合物5c仅提高25%;化合物的除草活性在68%~72%之间。 以石墨烯修饰的玻碳电极为工作电极,在Britton-Robison缓冲溶液中,研究了目标化合物电化学行为。 结果表明,在pH值为2或3的溶液中,合成目标化合物具有良好的氧化还原可逆性,氧化峰电流对数(lg Ipc)与扫描速度对数(lg v)、浓度对数(lg c)均呈现良好线性关系,目标化合物(5a~5d)的电子转移过程均受吸附-扩散混合控制,该类化合物的循环伏安法最低检出限为10-5 mol/L。 相似文献
96.
Dyanne L. Cruickshank Mircea Bogdan Sorin I. Fărcas Susan A. Bourne 《Supramolecular chemistry》2013,25(6):406-414
The formation of inclusion complexes between the native cyclodextrins (CDs) and the urea herbicide cycluron has been investigated both in solution and in the solid state. Single-crystal X-ray structures of both the uncomplexed guest and the β-CD·cycluron complex were determined while powder X-ray diffraction was used to confirm complexation between γ-CD and cycluron in the solid state. Solution-state complexation between the herbicide and α-, β- and γ-CD was established using 1H NMR spectroscopy and isothermal titration calorimetry (ITC). From the 1H NMR spectroscopic studies 1:1 complex stoichiometry was indicated in all cases and association constant values (K) were determined as 228, 3254 and 155 for the complexes α-CD·cycluron, β-CD·cycluron and γ-CD·cycluron, respectively. Assigning a 1:1 host–guest ratio, the ITC technique produced K values of the same order as those determined using the spectroscopic method. The thermodynamic parameters ΔH, ΔS and ΔG obtained using ITC provide insights into the driving forces involved during complex formation. 相似文献
97.
Ahmed Rehab Ahmed Akelah Maisa M. El‐Gamal 《Journal of polymer science. Part A, Polymer chemistry》2002,40(14):2513-2525
A series of polymer–clay composites carrying metribuzin as herbicide moieties were prepared. Linear copolymers containing metribuzin via an imide linkage were prepared by the free‐radical polymerization of metribuzin monomer (N,N‐diacryloyl metribuzin) with different comonomers. The intercalation of the copolymers onto montmorillonite through a cationic exchange process was carried out and yielded metribuzin composite products. The prepared materials were characterized with a wide variety of analytical techniques, including gel permeation chromatography, NMR, IR, elemental microanalysis, gravimetric analysis (calcination), and swelling measurements. The release rates for the prepared materials were investigated in media of different pHs with an ultraviolet spectrophotometer. Also, these compounds were studied for the control of herb growth. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 2513–2525, 2002 相似文献
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99.
The determination of triazine herbicides by ultrasonic‐assisted ionic liquid microextraction coupled with high‐performance liquid chromatography was described. 1‐Hexyl‐3‐methylimidazolium hexafluorophosphate ([C6MIm][PF6]) was used as the extraction solvent and some extraction parameters, including volume of [C6MIm][PF6], extraction temperature and time, salt concentration and pH values of sample solution, were examined and optimized. The isolation of the target compounds from the matrix was found to be efficient when triazines in 10 mL of sample solution was extracted with 100 µL of [C6MIm][PF6] for 40 min at 50°C. The detection limits for the triazine range from 0.36 to 1.41 µg·L?1. The satisfactory recoveries (82.3% –120.3%) with relative standard deviations ≦10.1% were obtained for the four triazine herbicides from six kinds of practical water samples. 相似文献
100.