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Xue Yan SHI Hong Chao GUO Zhen QIAO Shi Cong HOU Min WANG* Key Laboratory of Pesticide Chemistry Application Technology College of Applied Chemistry China Agricultural University Beijing 《中国化学快报》2002,(10)
For high bioactivity of chiral pesticides, more and more chiral isomers are prepared by enantiomer resolution or asymmetric synthesis, and the sales of chiral pesticides continuously increase in recent years1. 1S-Allethrone I and 1S-propargyllone II are indispensable intermediates for synthesizing 1S-bioallethrin and prallethrin respectively, which are representatives of chiral pesticides. Usually, 1S enantiomers of allethrone and propargyllone are more active than their 1R enantiomers wh… 相似文献
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烯丙基乙基醚接枝聚硅氧烷气相色谱固定相的研究 总被引:1,自引:0,他引:1
合成了侧链为烯丙基乙基醚的聚硅氧烷气相色谱固定相,静态法涂柱,评价了其色谱性能.该固定相柱效高,易于涂渍,耐温达290℃,分离选择性好,适用于醇类和酯类的分离以及白酒样品的分析. 相似文献
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用动态涂敷法制备了对甲苯磺酸正丁铵玻璃毛细管柱柱1(固定液浓度为7.5%,柱尺寸为35m×0.35mmi.d.)和柱2(固定液浓度为9.2%,柱尺寸为35m×0.30mmi.d.),所用溶剂是丙酮和甲醇(2:1V/V)的混合溶剂,并对柱性能进行了考察。结果表明,这种色谱固定相具有较强的极性并对饱和烃、芳香烃、饱和酸、芳香酸、极性异构体等具有良好的分离效果。 相似文献
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Using two β-cyclodextrin derivatives (CDs) with long chain of acyl groups as chiral stationary phases (CSPs) of capillary gas chromatography (CGC), the enantiomers of racemic allethrone and propargyllone were well resolved after derived with acetyl chloride. The enantiomer excess values (e.e.%) of 1S-allethrone and 1S-propargyllone were also determined successfully using these CDs. 相似文献
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报道了一种手性金属有机笼[Cu12(LPA)12(H2O)12](PA=L-苯丙氨酸, MOC-PA)作为毛细管电泳分离新型固定相的研究. 采用X射线粉末衍射仪、 红外光谱、 热重分析和扫描电子显微镜对该材料进行了表征, 结果表明该手性金属有机笼具有良好的热稳定性和空间结构. 利用该材料制备的毛细管色谱柱具有良好的手性识别能力, 可拆分1,2-二苯基乙二醇、 佐匹克隆、 4-甲基二苯基甲醇和茴香偶姻等手性药物, 也能拆分位置异构体硝基苯酚. 通过对拆分1,2-二苯基乙二醇、 佐匹克隆、 4-甲基二苯基甲醇和茴香偶姻进行最佳条件的探究, 得出电压、 缓冲溶液浓度及pH值在毛细管电泳中对手性样品分离度的影响. 采用佐匹克隆进行毛细管柱的重现性研究表明, 用该材料制备的毛细管电泳色谱柱具有一定的稳定性和重现性. 可见, 金属有机笼是一种良好的毛细管电泳手性固定相, 有一定的手性拆分能力, 在色谱分离中有较好的发展前景. 相似文献
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《Analytical letters》2012,45(13):2679-2690
ABSTRACT High-speed capillary electrochromatography was developed on both short and long packed columns with 2 μm non-porous ODS as the stationary phase. Factors that affect the analysis time of samples, such as voltage, electrolyte concentration, pH and organic modifier concentration in the mobile phase, were studied systematically. Fast analysis of aromatic compounds within 13 seconds was realized with column efficiency of 573,000 plates/m and a R.S.D.% of the retention times of all components in 8 consecutive injections below 1.0%, which demonstrated the high efficiency and high reproducibility of such a technique. In addition, DNPH derived aldehydes and ketones in both standards and environmental samples were separated with high speed. 相似文献
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An acidic water stationary phase is used for the analysis of carboxylic acids in capillary gas chromatography (GC). Under regular pH 7 operating conditions, these analytes are largely ionized and elute poorly, if at all, from the water phase. However, by adjusting the phase to pH 2, it is found that various acids are neutralized and can be readily eluted and separated in the system. Sulfamic acid is found to provide a stable pH for the water phase over time, whereas hydrochloric acid and other more volatile additives quickly evaporate from the column. Under optimal low pH conditions, the acidic analytes yield good peak shape and are readily observed for masses investigated down to 5 ng on-column. By comparison, on a conventional non-polar capillary GC column, the same analytes display threefold more peak tailing and are not detected for masses below 30 ng on-column. Through altering the phase pH, it is found that the selectivity between certain analytes can be potentially enhanced depending on their respective pKa values and/or ionizability. The analysis of various different samples containing carboxylic acids is demonstrated and the results indicate that this approach can possibly offer unique and beneficial selectivity in such determinations. 相似文献
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新型侧链聚硅氧烷液晶高分子用作毛细管柱气相色谱固定液 总被引:1,自引:0,他引:1
1 引 言寻求高选择性固定液是当今毛细管柱气相色谱研究的重要课题之一。1982年,Finkelmann等首次把侧链聚硅氧烷高分子液晶用作气相色谱固定液,成功地分离了二环芳烃异构体2,3-二甲萘、1,4-二甲萘和二苯甲烷。侧链聚硅氧烷高分子液晶易涂渍,选择性和热稳定性皆优于低分子液晶。本文对两种新型侧链聚硅氧烷液晶高分子用作气相色谱固定液进行了探讨。2 实验部分2.1 仪器与试剂 SP-3400气相色谱仪(北京分析仪器厂),氢火焰离子化检测器(FID)。蒽、菲、芴混合物(溶剂二氯甲烷),邻、间、对二甲苯混合物,二甲酚异构体混合物(溶剂… 相似文献
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Fullerenesciencehasdevelopedquiterapidlysincethediscoveryofthebulkpreparationmethodoffullerenesinl99o.Duetotherichnessofunusualstructuresandoutstandin2thepreparationofaHPLCmicrocolumn,whichwasshowntobeabletoseparatCamixtureofCooandC7oandalsoamixtureofcalixarenesl.AfulleropyrrolidinederivativewhichisattachedcovalentlytosilicagelinHPLCshowedmolecularrecognitiontowardscalixarenes,cyclodextrinsandsomehelical-shapedpeptides'.Surface-linkedCoc7o-polystyrenedivinylbenzenebeadsasachromatographicm… 相似文献
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本文研究了缬氨霉素的气相色谱特性, 考察了它们对一些难分离物质对、位置异构体以及一些手性化合物的分离效果. 除文献[3]外, 目前尚未见到有关将环状肽作为色谱固定相的报道. 相似文献