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Collin OL Niegel C Derhodes KE McCord BR Jackson GP 《Journal of forensic sciences》2006,51(4):815-818
The detection of a mixture of nine explosive compounds, including nitrate esters, nitroaromatics, and a nitramine in less than 140 sec is described. The new method employs a commercially available pulsed-discharge electron capture detector (PDECD) coupled with a microbore capillary gas chromatography (GC) column in a standard GC oven to achieve on-column detection limits between 5 and 72 fg for the nine explosives studied. The PDECD has the benefit that it uses a pulsed plasma to generate the standing electron current instead of a radioactive source. The fast separation time limits on-column degradation of the thermally labile compounds and decreases the peak widths, which results in larger peak intensities and a concomitant improvement in detection limits. The combination of short analysis time and low detection limits make this method a potential candidate for screening large numbers of samples that have been prepared using techniques such as liquid-liquid extraction or solid-phase microextraction. 相似文献
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高校社科学报要适应期刊市场竞争的需要,提升学术质量,加强栏目创新,就要依托学科建设。另外,打造高校学报品牌栏目,还能促进学校的学科建设,二者可互促互动,共同发展。 相似文献
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目的 建立柱前衍生化反相高效液相色谱法测定蝉蜕中天冬氨酸、酪氨酸和缬氨酸3种氨基酸含量的方法。方法 采用酸水解法制备氨基酸样品溶液,以异硫氰酸苯酯柱前衍生化后进行高效液相色谱分析。采用Kromasil C18色谱柱(250 mm×4.6 mm),梯度洗脱,流动相A为0.1 mol/L醋酸钠缓冲液- 乙腈(93∶7),流动相B为乙腈- 水(4∶1),流速1.0 mL/min,柱温为43 ℃,检测波长254 nm,进样量20 μL。结果 氨基酸衍生溶液在36 h内保持稳定,3种氨基酸在线性范围内峰面积与浓度的相关系数均大于0.999 0,加样回收率(n=6)分别为95.62%、101.26%和100.00%。结论 所建立的检测方法稳定可靠,精密度和重复性良好,可用于蝉蜕中天冬氨酸、酪氨酸、缬氨酸含量测定。 相似文献
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[摘要]目的 研究姜黄色素(curcuminoids, Cur)中姜黄素(curcumin, Cur Ⅰ)、脱甲氧基姜黄素(demethoxycurcumin, Cur Ⅱ)和双脱甲氧基姜黄素(bisdemethoxycurcumin, Cur Ⅲ)3种单体的分离、纯化工艺。方法 采用以氯仿 甲醇溶剂系统进行梯度洗脱的柱层析法分离Cur中的3种单体,并采用重结晶法对其进行纯化,通过薄层色谱、熔点测定及高效液相色谱法(high performance liquid chromatography,HPLC)对3种姜黄素单体的进行检测并计算纯度。结果 可获得3种高纯度的姜黄素单体,HPLC测定结果分别为Cur Ⅰ纯度99.47%、Cur Ⅱ纯度99.64%、Cur Ⅲ纯度98.64%。结论 硅胶柱层析法合理、科学,效率高,可为姜黄素单体的进一步研究与开发应用提供实验依据。 相似文献