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高效液相色谱法测定食品中有机酸 总被引:8,自引:2,他引:6
前言 有机酸是食品重要的组成成分之一,它与食品加工、贮存、质量评价等密切相关,因此越来越受到人们的重视。近年来,高效液相色谱(多采用离子色谱和离子交换色谱)已广泛应用于食品中有机酸的分析。 本文采用反相色谱,以0.6%KH_2PO_4(pH 2.65)为流动相,测定了酱油、黄酒、豆奶中的八种有机酸,取得了很好的分离效能。此法具有灵敏度高、重现性和回收率好、流动相价格便宜等特点。 相似文献
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脱落酸(abscisc acid,ABA)是一种重要的植物激素,植物组织中脱落酸的测定在植物生理研究中占有重要地位.ABA的测定方法有多种,如放射免疫法,固相酶免疫法及各种色谱分析方法等.近年来,采用色谱法进行测定的报道居多,特别是高效液相色谱法.相对于其它方法来说,具有分析速度快、检测的浓度范围宽等特点,应用越来越广泛。本文在国内外已有的一些工作基础上,利用反相高效色谱法对几种水果中的顺式ABA进行测定,在样品的前处理及分析条件的选择上作了一些改进,与其它HPLC方法比较,本法具有干扰小,回收率好,灵敏度高,分析操作更为简单、快速等特点。 相似文献
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手性分离在生物医药等领域具有重要意义。高效液相色谱(HPLC)因其经济、快速、高效等特点被广泛应用于手性化合物的分离分析中。手性固定相(CSP)是HPLC实现手性分离的核心,而制备有效CSP的关键在于手性选择剂的筛选。近年来,大量文献报道了新型CSPs的制备,其中键合型CSPs因具有溶剂耐受性和较高稳定性等优点受到了广泛关注。该文对近年来以手性单分子、多糖、环糊精、大环抗生素、冠醚、杯芳烃及生物碱等为手性选择剂制备的新型键合型CSPs进行了归纳整理,并对其发展前景进行了展望。 相似文献
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高效液相色谱法测定空气中苯胺 总被引:3,自引:0,他引:3
苯胺为重要的芳香伯胺,它广泛地应用于化工、印染和制药等工业生产中,是合成药物、染料、炸药等的重要原料之一。因苯胺有毒,以往监测方法多采用盐酸萘乙二胺比色法,此法最大缺点不是特异性反应,苯胺类化合物均起反应,干扰大,且采用吸收液采样不如固体吸附剂代表性强,传递方便,保存期长。本文参考有关资料,研究建立了国内不曾报道的液相色谱法,应用硅胶采样,甲醇解吸,以Zorbax—ODS柱分离,紫外吸收检测器检测,其解吸效率达96%以上,合并变异系数(CV)为7.3%,最小检测浓度为3μg/m~3,硅胺吸附苯胺保存两周后回收率仍达95%。 相似文献
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固相萃取-高效液相色谱法测定果蔬中农药马拉硫磷残留量 总被引:1,自引:0,他引:1
马拉硫磷(商品名Malathion,又名马拉松)是一种农业上应用广泛的高效、低毒、接触性有机磷类杀虫剂,可用于拌粮作防护剂使用,也可用于空仓、器材和加工厂等的消毒。其对人畜毒性较低,在高等动物体内代谢速度快、代谢毒性小、残效期短并具有触杀、胃毒、熏蒸等作用[1]。在强氧化剂作用下,马拉硫磷能被氧化成马拉氧磷,在生物体中氧化酶的作用下能被氧化代谢成马拉氧磷[2],因此其毒理是它经过体内活化后,生成的氧化马拉硫磷对胆碱酩酶有抑制作用[3],致使以乙酞胆碱为传导介质的神经远于过度兴奋状态,最后转入抑制和衰竭[4]。由于其使用面积广,… 相似文献
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Chemistry is a central, practical and creative discipline. The development of chemistry plays an important role in the progress of science and society, as well as the improvement of the quality of human life. This paper introduces the chemical knowledge of stone, concrete, glass and other inorganic nonmetallic building materials by the anthropomorphically story. Taking nanomaterials as an example, the prospect of building materials development in the future is put forward. 相似文献
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The syntheses of 3β-hydroxy-5β-carda-14, 20:22-dienolide (= «β»-anhydro-), 3β-hydroxy-5β-carda-8:14, 20:22-dienolide (= «α»-anhydro-) and «δ»-anhydro-digitoxigenin (= probably 3β-hydroxy-5β, 14β-carda-8, 20:22-dienolide) by the best ways known to date, have been described. «δ»-Anhydro-digitoxigenin represents the thermodynamically most stable isomer. In this isomer the double bond in position 8 is unaffected by hydrogenation with Pt in acetic acid; with perbenzoic acid an epoxide results from which, on hydrogenation, the double bond can be regenerated in its original position. Analogous reactions are known to occur in the 8:14-epoxides. 相似文献
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Scott RT Milios CJ Vinslava A Lifford D Parsons S Wernsdorfer W Christou G Brechin EK 《Dalton transactions (Cambridge, England : 2003)》2006,(26):3161-3163
[Mn(IV)Mn(II)3] triangular units directed by the presence of tripodal alcohols self-assemble in the presence of azide and acetate ligands to form either a [Mn24] "wheel" or a [Mn32] "cube". 相似文献
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Chemical probes are valuable tools for the investigation of biochemical processes, diagnosis of disease markers, detection of hazardous compounds, and other purposes. Therefore, the development of chemical probes continues to grow through various approaches with different disciplines and design strategies. Fluorescent probes have received much attention because they are sensitive and easy-to-operate, in general. To realize desired selectivity toward a given analyte, the recognition site of a fluorescent probe is designed in such a way to maximize the binding interactions, usually through weak molecular forces such as hydrogen bonding, toward the analyte over other competing ones. In addition to such a supramolecular approach, the development of fluorescent probes that sense analytes through chemical reactions has witnessed its usefulness for achieving high selectivity, in many cases, superior to that obtainable by the supramolecular approach. Creative incorporations of the reactive groups to latent fluorophores have provided novel chemical probes for various analytes. In this feature article, we overview the recent progress in the development of turn-on fluorescent probes that are operating through chemical reactions triggered by target analytes. Various chemical reactions have been implemented in the development of many reactive probes with very high selectivity and sensitivity toward target analytes. A major emphasis has been focused on the type of chemical reactions utilized, with the hope that further explorations can be made with new chemical reactions to develop reactive probes useful for various applications. 相似文献
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Opsteen JA Brinkhuis RP Teeuwen RL Löwik DW van Hest JC 《Chemical communications (Cambridge, England)》2007,(30):3136-3138
Polymersomes, composed of amphiphilic polystyrene-block-poly(acrylic acid) (PS-b-PAA), with the periphery being covered with azide groups, were used for further functionalization using "click" chemistry. 相似文献
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