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化学发光法测定铬的进展 总被引:8,自引:0,他引:8
综述了化学发光测定铬的进展、文中叙述了化学发光试剂、影响因素、选择条件、流动注射及其测定方法,初步探讨了铬的化学发光机理. 相似文献
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A new and sample technique for the simultaneous determination of trace arsenic, antimony, bismuth and selenium in biologic samples by hydride generation-four-channel nondispersive atomic fluorescence spectrometry was development. The conditions of instrumentation and hydride generation of arsenic, antimony, bismuth and selenium were optimized. For reducing hexavalent Se to the tetravalent state was to heat the sample with 6 mol l−1 HCl, and then pre-reducing pentavalent As and Sb to the trivalent state was achieved by the addition of 0.05 mol l−1 thiourea. The interferences of coexisting ions were evaluated. Under optimal conditions, the detection limits for As, Sb, Bi and Se were determined to be 0.03, 0.04, 0.04 and 0.03 ng ml−1, respectively. The precision for seven replicate determinations at the 5 ng ml−1 of As, Sb, Bi and Se were 0.9, 1.2, 1.3 and 1.5% (R.S.D.), respectively. The proposed method was successfully applied to the simultaneous determination of As, Sb, Bi and Se in a series of Chinese certified biological reference materials using simple aqueous standard calibration technique, the results obtained are in good agreement with the certified values. 相似文献
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极谱法测定人发中痕量铜的研究 总被引:4,自引:0,他引:4
研究了痕量铜与CNS-及TriTonX 30 5非离子表面活性剂形成多元配合物 ,用示波极谱分析法测定痕量铜的新方法 .新方法铜的析出限为 1× 10 -10 g/mL ,工作曲线线性响应浓度范围为 5× 10 -9~ 5× 10 -7g/mL ,回收率为 98%~ 10 3% .直接用于人发、血清等样品中痕量铜的测定 ,其结果与原子吸收分光光度法测定结果对照相吻合 相似文献
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建立固相萃取-离子交换色谱法测定浓缩苹果汁中苯菌灵、多菌灵和噻菌灵的残留量。样品直接用水稀释后,于80 ℃下将苯菌灵完全转化为多菌灵,再经SCX固相萃取柱富集,采用LC-SCX离子交换色谱柱(25 cm×4.6 mm,5 μm)分离,二极管阵列检测器检测,以0.1 mol/L KH2PO4溶液(pH 2.5)-乙腈(体积比为70 ∶30)为流动相,在1.0 mL/min下等度洗脱,于282 nm波长下检测。在0.02~2.0 mg/L范围内,多菌灵和噻菌灵的峰面积与其浓度呈良好的线性关系,最低检出限均可达到0.004 mg/kg,回收率为94.2%~100.4%,相对标准偏差低于4.2%。该方法简便、快速、灵敏、准确,可用于浓缩苹果汁中苯菌灵、多菌灵和噻菌灵残留量的检测。 相似文献
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研究了Bond Elut ENV新型固相萃取柱在食用植物油中苯并[a]芘快速检测中的应用,建立了快速测定食用植物油样品中苯并[a]芘残留量的固相萃取/液相色谱/荧光检测法。样品用正己烷溶解,固相萃取净化,SUPELCOSILTMLC-PAH(25 cm×4.6 mm,5μm)色谱柱分离,以乙腈-水(95∶5)为流动相,荧光检测(λex=297 nm,λem=408 nm),外标法定量。苯并[a]芘的检出限为0.3μg/kg,在1.0~50.0μg/L范围内线性关系良好,相关系数为0.999 6,方法的回收率为79%~102%,相对标准偏差不高于9.4%。该方法准确、实用、简便、快速,在食用植物油的苯并[a]芘残留量检测方面有广泛的应用前景。 相似文献
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AuR2+-鲁米诺-K2S2O8化学发光体系与应用 总被引:3,自引:0,他引:3
研究了 8 羟基喹啉 (HR)与Au(Ⅲ )形成的配合物AuR+ 2 ,对K2 S2 O8氧化鲁米诺的增强作用 ,基于此建立了金的化学发光分析新方法 .以 8 羟基喹啉为配位体时 ,Au(Ⅲ )的检出限为 8× 10 -11μg/L ,工作曲线响应浓度范围在 1× 10 -9~ 1× 10 -7μg/L ,测定 1× 10 -7μg/LAu(Ⅲ )离子的RSD为 2 .0 % .配合物化学发光法检测硅酸盐单矿物晶格中痕量金可获得较好的分析结果 相似文献
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A simple, stable and sensitive electrogenerated chemiluminescence (ECL) detector was developed. It was based on tris(2,2-bipyridyl)ruthenium(II) (Ru(bpy)32+) immobilized on the surface of a Pt wire with Nepem-105D ion exchange solution. The detector was prepared by inserting a Pt wire with immobilized Ru(bpy)32+ (working electrode) into a capillary tube, followed by inserting another Pt wire (counter electrode) in this tube and sealing. ECL behavior was investigated using ofloxacin as an analyte. Under optimal conditions, stable ECL intensity was obtained. This detector has been used in HPLC-ECL for the determination of multiple target fluoroquinolone residues in milk. There is no post column reagent addition, which would dilute the analytes, potentially leading to chromatographic band-broadening. The system is very simple with low dead volume, low baseline and background noise, together with high sensitivity and stability. The as-prepared ECL detector, when was used for the determination of ofloxacin, pefloxacin, enrofloxacin and difloxacin in milk, demonstrated adequate sensitivity to allow quantification of trace FQ levels in commercial milk samples. One or more of the target FQ analytes were present at levels above the LOD of the new ECL detector in each and every one of the 22 milk samples analysed. 相似文献