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81.
82.
高效液相色谱法测定化妆品中的保泰松 总被引:1,自引:0,他引:1
建立了化妆品中保泰松的高效液相色谱分析法.采用甲醇超声提取样品,氨基固相小柱净化富集,以C18色谱柱(4.6 mm×250 mm,5μm)分离,流动相为20 mmol/L乙酸铵水溶液、甲醇和乙腈,流速1.0 mL/min,检测波长270 nm,柱温25℃,进样量10 μL.该方法的检出限为2.0 mg/kg,线性范围0.2~100.0μg/mL,加标回收率86.1% ~90.5%,相对标准偏差为5.79%~9.21%. 相似文献
83.
84.
[方法]通过田间试验和液相色谱分析技术研究了75%代森锰锌代谢物乙撑硫脲在茎和叶中残留动态和最终残留量.[结果]吉林抚松田间试验结果表明:施药剂量为推荐剂量的2倍(6250 g a.i./hm2)时,乙撑硫脲在茎和叶中原始沉积量分别为0.782、8.23 mg/kg;半衰期分别为4.9、19.5 d.施药1次,测得茎中乙撑硫脲残留量14d后低于欧洲规定的MRL值(0.05 mg/kg),而叶中乙撑硫脲残留量均高于欧洲规定的MRL值(0.05 mg/kg).[结论]综合多方面因素,按照推荐剂量3 125 g a.i./hm2处理,建议我国在茎上乙撑硫脲的MRL值可暂定为0.05 mg/kg,茎安全间隔期为14 d,而叶上的残留量较高,建议MRL值可暂定为0.50 mg/kg,叶安全间隔期无法确定,施药次数为1次. 相似文献
85.
浅谈液相色谱仪的管理与维护 总被引:1,自引:0,他引:1
介绍了高效液相色谱仪的结构组成和发展,阐述了流路泵系统、色谱柱和几种常用检测器的管理与维护,为液相色谱分析工作,提供一些值得借鉴的仪器管理与维护经验。 相似文献
86.
中药化学成分复杂,其成分分析一直存在着分离难度大、分析时间长等问题,高效液相色谱法(HPLC)是中药质量分析最重要的手段之一。综述了HPLC在中药化学成分分析中的应用。 相似文献
87.
[目的]建立三苯基乙酸锡在水稻植株和土壤中残留量的高效液相色谱检测方法。[方法]样品用乙腈提取后,二氯甲烷萃取,经酸性氧化铝柱净化,以乙腈-0.5%磷酸水(体积比30∶70)为流动相,用紫外检测器测定。[结果]水稻植株和土壤样品中三苯基乙酸锡的添加平均回收率分别为86.4%~102.9%、88.8%~105.2%,相对标准偏差分别为5.1%~10.2%、2.4%~8.3%,最小检出量为1.0×10-10 g,最低检测质量分数为2.0×10-3 mg/kg。[结论]方法操作简便,符合农药残留分析的要求,为其他作物中三苯基乙酸锡残留量的测定提供参考。 相似文献
88.
Molecularly imprinted polymers: present and future prospective 总被引:2,自引:0,他引:2
Vasapollo G Sole RD Mergola L Lazzoi MR Scardino A Scorrano S Mele G 《International journal of molecular sciences》2011,12(9):5908-5945
Molecular Imprinting Technology (MIT) is a technique to design artificial receptors with a predetermined selectivity and specificity for a given analyte, which can be used as ideal materials in various application fields. Molecularly Imprinted Polymers (MIPs), the polymeric matrices obtained using the imprinting technology, are robust molecular recognition elements able to mimic natural recognition entities, such as antibodies and biological receptors, useful to separate and analyze complicated samples such as biological fluids and environmental samples. The scope of this review is to provide a general overview on MIPs field discussing first general aspects in MIP preparation and then dealing with various application aspects. This review aims to outline the molecularly imprinted process and present a summary of principal application fields of molecularly imprinted polymers, focusing on chemical sensing, separation science, drug delivery and catalysis. Some significant aspects about preparation and application of the molecular imprinting polymers with examples taken from the recent literature will be discussed. Theoretical and experimental parameters for MIPs design in terms of the interaction between template and polymer functionalities will be considered and synthesis methods for the improvement of MIP recognition properties will also be presented. 相似文献
89.
Fabiano-Tixier AS Elomri A Blanckaert A Seguin E Petitcolas E Chemat F 《International journal of molecular sciences》2011,12(11):7846-7860
Quinas contains several compounds, such as quinoline alkaloids, principally quinine, quinidine, cinchonine and cichonidine. Identified from barks of Cinchona, quinine is still commonly used to treat human malaria. Microwave-Integrated Extraction and Leaching (MIEL) is proposed for the extraction of quinoline alkaloids from bark of Cinchona succirubra. The process is performed in four steps, which ensures complete, rapid and accurate extraction of the samples. Optimal conditions for extraction were obtained using a response surface methodology reached from a central composite design. The MIEL extraction has been compared with a conventional technique soxhlet extraction. The extracts of quinoline alkaloids from C. succirubra obtained by these two different methods were compared by HPLC. The extracts obtained by MIEL in 32 min were quantitatively (yield) and qualitatively (quinine, quinidine, cinchonine, cinchonidine) similar to those obtained by conventional Soxhlet extraction in 3 hours. MIEL is a green technology that serves as a good alternative for the extraction of Cinchona alkaloids. 相似文献
90.
Tsuyoshi OchiaiYuichi Iizuka Kazuya NakataTaketoshi Murakami Donald A. TrykAkira Fujishima Yoshihiro KoideYuko Morito 《Diamond and Related Materials》2011,20(2):64-67
The electrochemical decomposition of environmentally persistent perfluorooctanoic acid (PFOA) was achieved by the use of a boron-doped diamond (BDD) electrode. The PFOA decomposition follows pseudo-first-order kinetics, with an observed rate constant (k1) of 2.4 × 10− 2 dm3 h− 1. Under the present reaction conditions, k1 increased with increasing current density and saturated at values over 0.60 mA cm− 2. Therefore, the rate-limiting step for the electrochemical decomposition of PFOA was the direct electrochemical oxidation at lower current densities. In the proposed decomposition pathway, direct electrochemical oxidation cleaves the C-C bond between the C7F15 and COOH in PFOA and generates a C7F15 radical and CO2. The C7F15 radical forms the thermally unstable alcohol C7F15OH, which undergoes F− elimination to form C6F13COF. This acid fluoride undergoes hydrolysis to yield another F− and the perfluorocarboxylic acid with one less CF2 unit, C6F13COOH. By repeating these processes, finally, PFOA was able to be totally mineralized to CO2 and F−. Moreover, whereas the BDD surface was easily fluorinated by the electrochemical reaction with the PFOA solution, medium pressure ultraviolet (MPUV) lamp irradiation in water was able to easily remove fluorine from the fluorinated BDD surface. 相似文献