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Abstract

Inorganic long-chain polyphosphates were fractionated by Sephadex G-100 and G-50 columns. Fractions whose average chain lengths, [nbar], were 20–150 and 10–50 were obtained by the G-100 and G-50 columns, respectively. By rechromatography of these fractions, linear relationship was found for the plots of the elution volumes vs. logarithms of the [nbar]n values. By the use of this relationship, chain length distribution analysis could be performed.  相似文献   

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Summary Gel chromatography on Sephacryl S-400 HR was used to fractionate a type A and a type B gelatin on a semi-preparative scale. Fractionation was performed at 40 °C in 50 mM ammonium acetate, 0.02% (w/v) sodium azide. Five fractions, enriched in microgels, -chains, -chains, -chains and subfragments, were isolated. Their molar mass distribution was controlled by FPLC on Superose 6 and SDS-PAGE. No significant differences in amino-acid composition and hexose content were observed between the original gelatins and their fractions. The specific absorption coefficient at 230 nm was found to be the same for both type A and type B gelatin and the chromatographic fractions (2.0 L·g–1·cm–1).Presented at: International Symposium on Separation and Characterization of Natural and Synthetic Macromolecules, Amsterdam, The Netherlands, February 5–7, 2003  相似文献   

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Abstract

Some problems in organic carbon characterization are briefly discussed. A new chromatographic multi-method for the direct characterization of organic matter in original waters with the simultaneous determination of UV-Vis, fluorescence, DOC, TIC, and organically bound nitrogen (DON) is described. Some applications with UV-Vis and DOC (“CODOC”) detection are presented.  相似文献   

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任吉存  黎众魁 《分析化学》1996,24(3):330-332
本文将毛细管凝胶电泳方法用于低聚核苷酸及DNA合成产物的分离检测,并探讨了低聚核苷酸的淌度与其碱基数的关系以及迁移时间和相对迁移时间的重现性。  相似文献   

7.
建立了凝胶渗透色谱一气相色谱质谱(GPC~GC=MS)法测定花生中6种除草剂(氟乐灵、异恶草酮、甲草胺、二甲戊乐灵、乙氧氟草醚、喹禾灵)农药残留的方法。样品经乙腈提取,氨基固相萃取柱和凝胶渗透色谱净化,在选择离子扫描(SIM)模式下进行气相色谱质谱法测定,外标法定量。6种除草剂浓度在0.02-1.00mg/L范围内与色谱峰面积呈良好的线性,线性相关系数为O.9949~0.9998,添加回收率为77.8%-101.6%,测定结果的相对标准偏差为4.4%~11.4%(月=5),方法的检出限为0.1~1.3μg/kg。  相似文献   

8.
Gel filtration chromatography using a TSKgel G2000 SW column coupled with differential refractive index detection was used to analyse five grades of polyvinyl alcohol. Limits of detection and quantification for the assay were 0.14 mg mL–1, 0.47 mg mL–1 respectively. The inter and intra-day co-efficient of variance were both <7%. There was a significant difference (p<0.05, n=5) between the calibration curves across the five grades of PVA due to a refractive index range of 13.0790 –1.3181 (n=3). The assay accuracy was 98.99% ± 8.97% (n=5) and 90.60% ± 7.87% (n=5) of a spiked PVA sample was recovered from a commercial formulation.  相似文献   

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Methods are described for the determination of chlorinated hydrocarbons at levels of parts per billion in water and nonaqueous environmental samples by gas chromatography with electron-capture detection. C18, Florisil, alumina N and silica Sep-Pak cartridges were compared to evaluate their cleanup ability. The accuracy of the results of this analytical technique was proved by the analysis of a certified reference material (lake sediment EC-2).  相似文献   

10.
《Analytical letters》2012,45(1):75-84
Abstract

We analyzed the solid state and aqueous solution electron spin resonance (esr) spectra of Oyster River and Podzol soil fulvic and humic acids. Because the aqueous solution esr spectra mimic the behavior of the model compound para-benzosemiquinone, we conclude that semiquinone free radicals predominate in fulvic acid. In addition a decrease in spin concentration at a potential of 0.20 volts (vs. SCE) demonstrates that the semiquinone radicals are at least partially responsible for the reducing capability of humic materials. From the above results we devised a quantitative semiquinone analysis for humic materials.  相似文献   

11.
《Analytical letters》2012,45(10):945-955
Abstract

Ortho-, meta- and para-isomers of various derivatives of phenols and aromatic acids have been separated on a cross-linked poly (ethyleneimine) coated silica gel micro-column liquid chromatography with very dilute carbonate or phosphate eluents.  相似文献   

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建立了凝胶渗透色谱-气相色谱/质谱法同时测定食用油中22种邻苯二甲酸酯的方法.方法具有良好线性,相关系数R均大于0.999,检测限在0.09~11.83 mg/kg之间,平均回收率在81.45%~113.90%范围内,相对标准偏差为1.55%~9.41%.采用该方法对国内食用油中邻苯二甲酸酯增塑剂进行检测,实际样品中检出邻苯二甲酸二异丁酯、邻苯二甲酸二丁酯和邻苯二甲酸二(2-乙基)己酯,可满足目前食用油中邻苯二甲酸酯的检测要求.  相似文献   

14.
建立了以固相萃取技术进行富集 ,高效液相色谱法进行分离和检测苯氧乙酸和 2 ,4 二氯苯氧乙酸的方法。环境水中的苯氧乙酸和 2 ,4 二氯苯氧乙酸用Sep PakC18Cartridge进行固相萃取。液相色谱的条件是 :Shim PackCLCODS柱为分析柱 ;甲醇 水 (9∶1,V/V)为流动相 ;流速为 1mL/min ;在UV 2 75nm波长下进行检测。本法具有良好的灵敏度和重现性  相似文献   

15.
在线富集胶束电动色谱法测定唾液中的唾液酸   总被引:1,自引:0,他引:1  
建立了1种测定唾液酸的在线富集胶束电动色谱法。首先研究了不同的表面活性剂(十二烷基硫酸钠、胆酸钠和脱氧胆酸钠)、背景电解质(磷酸盐、硼砂和3—环己胺—1—丙烷磺酸)、缓冲溶液的pH值及有机修饰剂(甲醇和乙腈)的加入对测定唾液酸的影响;其次研究了样品基体的组成及进样时间对富集效果的影响;最后考察了所建立方法的线性、检出限和重复性,并将该方法成功地应用于测定人体唾液中的唾液酸,在12min内完成分离。  相似文献   

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离子色谱法测定乙醛酸中的顺丁烯二酸和乙二酸   总被引:3,自引:0,他引:3  
采用抑制电导离子色谱法测定高浓度乙醛酸基体中痕量的顺丁烯二酸和乙二酸。将乙醛酸样品稀释至1 000倍体积后,采用高浓度的淋洗液,以高容量色谱柱对样品进行分析。实验结果表明,顺丁烯二酸和乙二酸最低检出限分别为12.7,19.6μg/L,重现性(n=5)分别为1.13%,1.11%,回收率分别为97.9%,94.7%。该方法具有较高的灵敏度,适用于乙醛酸的例行检测。  相似文献   

17.
超临界流体萃取和高效液相色谱法测定银杏酸   总被引:14,自引:0,他引:14  
沈刚  姚渭溪 《分析化学》2000,28(8):985-988
介绍了一种用改性的超临界二氧化碳萃取和离线的反相高效液相色谱分析银杏叶提取物中银杏酸含量的方法。对萃取条件进行了优化,结果表明以硅胶为载体,在30MPa、55℃条件下,8%甲醇作改性剂时的超临界二氧化碳对银杏酸有最理想的回收率和选择性。最小检测限为0.42mg/L。  相似文献   

18.
高效凝胶渗透色谱法在若干重质化工产物分析中的应用   总被引:2,自引:0,他引:2  
张昌鸣  张立安  杨建丽  刘振宇 《分析化学》2000,28(10):1248-1251
为配合酚醛树酯、十八烷基苯乙烯基醚聚合物新材料的生产、催化条件下煤直接液化的研究,建立了各试样分子量表征的高效凝胶渗透色谱法(HPGPC),高分辨地测定了分子量分布、重均分子量Mw、数均分子量Mn。表征了不同产品的组成特性,有效地指导了工艺生产和基础研究。  相似文献   

19.
《Analytical letters》2012,45(5):451-460
Abstract

Tris (acetylacetonato)cobalt(III) and tris(acetylacetonato)-chromium(III) have been eluted by gel chromatography through styrene-divinylbenzene copolymer gel using an organic solvent as an eluent. Elution counts of these chelates in these solvents reflect some mutual interactions between metal chelate, gel and solvent. When benzene or chloroform was used as an eluent, sieving effect seems to be dominant for the separation of these chelates. Discussions were done in relation to solubility parameters of the solvent, the complex and the gel.  相似文献   

20.
孙小峰  吴龙华  骆永明 《分析化学》2006,34(10):1375-1378
乙二胺二琥珀酸(EDDS)可应用于重金属污染土壤的强化植物修复或是土壤淋洗修复。但是现有的检测方法或过于复杂,或检出限太高。本研究建立了应用超声波萃取、硫酸铜衍生化和液相色谱,紫外检测器测定土壤、植物中EDDS含量的方法。其回收率为93%~118%,灵敏度较高;检出限达1.5μmol/L;重现性好,不受其它多种共存离子的干扰。  相似文献   

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