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平台石墨炉原子吸收法直接测定柑桔皮提取物中的痕量硒 总被引:2,自引:0,他引:2
本文提出了一种以正丁醇为溶剂、平台石墨炉原子吸收法直接测定油状样品中硒的方法。该方法简单、快速、无需样品 预处理,既提高了分析效率,又避免了预处理过程中硒的损失。 相似文献
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采用热解吸-电晕放电电离技术结合离子迁移谱,研究建立了化妆品中5种禁用卡因类化合物的现场快速筛查方法。化妆品样品无需前处理步骤,样品轻轻蘸取、滴加或喷雾在采样拭纸上,置于离子源样品槽中,采用热解吸-电晕放电电离技术实现样品中待测物的热解吸和离子化,随后以离子迁移谱进行快速筛查分析。5种卡因类化合物的检出限为10~50 ng,离子迁移谱分析时间小于20 ms,整个样品分析周期不超过1 min。本方法简便、快速、成本低廉,适用于化妆品中卡因类禁用组分的现场快速筛查。 相似文献
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微波消解技术在农业样品分析中的应用 总被引:7,自引:0,他引:7
利用光纤压力自控密闭微波消解系统对土壤和植株样品中重金属元素测定的影响进行了研究,确立了样品消解试剂、微波消解每件及样品预处理方法。结果表明,该方法与常压湿法消解相比,具有样品消解时间短、消解试剂用量少、样品污染小等特点,是准确可靠的土壤及植株样品中重金属元素检测样品消解处理方法。 相似文献
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李尉卿 《广东微量元素科学》2004,11(7):55-59
用ICP-AES法测定了大蒜中铝、铜、铁、锰、锶和锌等六种微量元素,试验了大蒜样品的分解方法,讨论了钙和磷对测定元素的干扰和溶液酸度对测定结果的影响,并进行了样品分析的精密度和准确度试验。用该法成功地进行了实际样品测定。 相似文献
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叙述了干灰法消化样品后,利用原子吸收光谱仪测定茶多酚中微量铜的方法。该法的回收率在90% ̄105%之间;对同一样品进行6次平行测定,其相对标准偏差为3.9%,结果可靠,方法简便;可用于实际样品分析。 相似文献
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电感耦合等离子体发射光谱法测定镁合金中铝锌锰硅铁铜镍铍锆 总被引:3,自引:0,他引:3
考察了镁合金光谱标准样品中多元素连续测定的电感耦合等离子体发射光谱方法,通过分析的优化遴选,建立了精确度良好的高至常量组分、低至痕量组分的检测步骤和仪器的不同工作模式,可满足镁和镁合金系列光谱标准样品的分析需要。 相似文献
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分光光度法测定汽油中的磷 总被引:3,自引:0,他引:3
提出了用磷钒钼酸分光光度法测定汽油中磷含量的方法,通过对汽油中可能存在的共存离子干扰进行了考察,确定了最佳测试条件。对合成标准样品分析,其相对误差小于±3.0%,相对标准偏差小于2.3%,对实际样品进行分析并进行了加标回收试验,磷回收率达到98.8%~103.9%。是一种快速、可靠测定汽油中磷含量的方法。 相似文献
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高效液相色谱法分离和测定3种植物内源激素 总被引:14,自引:1,他引:14
本文研究了高效液相色谱法测定吲哚-3-乙酸,脱落酸,赤霉素3种植物激素的条件,建立了一种从植物中提取这3种激素的样品处理方法,实际分析了植物样品,结果令人满意。 相似文献
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Summary The chromatographic behaviour of anions on paper strips treated with tri-n-octylamine (TOA) salts or Aliquat 336 and developed with aqueous solutions of acetic, formic, monochloroacetic or trifluoroacetic acids and their sodium salts was investigated. Liquid-liquid extraction of organic acids by 0.1 M solution of TOA in benzene as well as the anion exchange between benzene solutions of TOA salts or Aliquat 336 (in acetate form) in benzene and aqueous solutions of sodium halides was also studied. It was found that extraction increases in the following order of the acids: CH3COOOH<HCOOH<CH2CICOOH<CF3COOH; the relative affinity of organic anions to the quaternary alkyl-ammonium cation also increase in a similar order. The extraction of acid in excess over the amount necessary to neutralize the amine was observed for all four acids. The RF values of anions investigated depend markedly on the type of organic acids or their salts and their concentration in the mobile phase. Halide ions are more strongly retained on paper treated with Aliquat 336 as compared with TOA salts. The chromatographic systems investigated offer many possibilities to separate various anion mixtures.Parts and II: refs. [1, 2]. 相似文献
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Meire R. Silva Felipe N. Andrade Bruno H. Fumes Fernando M. Lanças 《Journal of separation science》2015,38(17):3071-3083
The concept of unified chromatography has been in existence for 50 years after the work of Giddings proposing that all modes of chromatography (gas chromatography, liquid chromatography, supercritical fluid chromatography and so on) may be treated together under a single unified theory. His idea was partially fulfilled 23 years later by Ishii, Takeuchi and colleagues, who demonstrated for the first time the possibility to analyze a complex sample containing substances with a wide range of boiling points and polarities in the same instrument and column, just by varying the mobile phase pressure and temperature to change from one chromatographic mode to another. This approach has been demonstrated through application to the separation of complex mixtures in several areas including crude oil, edible oils and polymers. Still, unified chromatography has not yet been fully developed. In the present work, we will review the fundamentals, instrumentation and several applications of the technique. Also discussed are the drawbacks that still hinder development, as well as the recent developments and trends in instrumentation and columns that suggest the most feasible ways forward to the full development of unified chromatography. 相似文献
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Although there are many simple thin-layer chromatography (TLC) separations, many more are complex and involve more than a few components, that means having to use special high-performance TLC (HPTLC) plates or microspotting or banding devices to increase its resolving power if developing in only one direction. However, adding a second development to perform two-dimensional TLC (2D TLC) allows even better resolution of complex samples. This is because different modes of chromatography are being invoked by the use of one stationary phase with two mobile phases, bilayer plates, graft TLC, or multidimensional TLC. This paper is a review of recent applications that have benefitted from using 2D TLC in its various forms. They were chosen for their variety of sample types as well as the unique choices of plates and/or mobile phases made by the researchers to yield improved separations. 相似文献
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W. Gołkiewicz 《Chromatographia》1981,14(11):629-632
Summary A method is described and experimentally verified permitting the determination of the optimal gradient programs in HPLC on the basis of isocratic TLC data. The proposed method has many advantages and can also be used in reversed-phase systems. A satisfactory agreement between the theoretical and experimental of VR/VO values has been confirmed. Some discrepancies for more strongly retained solutes are, probably due to the respective equilibrium and nonequilibrium state of the column in isocratic and gradient elution.Part I: Ref. [1]. 相似文献
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O. Bobleter 《Chromatographia》1996,43(7-8):444-446
Summary In November 1995, theDeutsches Museum, the world's largest technical museum, opened a new branch in Bonn, devoted to achievements after 1945. There, the first gas chromatographic system used by Erika Cremer and Fritz Prior, in 1945–47, in Innsbruck, is exhibited. The new display is described and the early activities of Erika Cremer and her students are summarized. 相似文献
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研究了蛋白质纯化制备的二种运行模式,其一,在色谱柱超载下纯化制备蛋白质模式,并成功地用离子交换色谱纯化制备了大豆中的胰蛋白酶,用反相液相色谱纯化了细胞色素C;其二,用溶质-溶质顶替色谱纯化制备了核糖核酸酶-A,并对顶替色谱过程中诸参数进行了讨论和选择。 相似文献