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A novel method for the determination of palladium as a metal ion model was developed by ion pair based surfactant-assisted microextraction (IP-SAME) and inductively coupled plasma-optical detection (ICP-OES). In this methodology, a cationic surfactant was used in extraction process. It has two fundamental functions: (1) the formation of an emulsified phase and (2) the ion pair formation with Pd(II) in the presence of iodide ions and making PdI42− extractable into organic phase (active microextraction). The effective parameters on the extraction recovery such as the types of extraction solvent and the surfactant, surfactant concentration, KI amount and HCl concentration of the sample were investigated and optimized. In the proposed approach, tetradecyl trimethyl ammonium bromide (TTAB) was used as emulsifier and ion pairing agent, and 1-octanol was selected as extraction solvent. Under the optimum conditions, the enhancement factor as large as 146 was obtained. The detection limit for palladium was 0.2 μg L−1, and the relative standard deviation (RSD) was 4.1% (n = 5, C = 10.0 μg L−1). The proposed method was applied for extraction and determination of palladium in different water samples. 相似文献
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Modifications were made on commercial SPME fiber assembly and SPME–LC interface to improve the applicability of SPME for LC. Polyacrylonitrile (PAN)/C18 bonded fuse silica was used as the fiber coating for LC applications because the fiber coating was not swollen in common LC solvents at room temperature. The inner tubing of SPME fiber assembly was replaced with a 457 μm outside diameter (o.d.) solid nitinol rod. And the coated fiber (o.d. 290 μm) was installed onto the nitinol rod. The inner diameter (i.d.) of the through hole of the ferrule in the SPME–LC interface was enlarged to 508 μm to accommodate the nitinol rod. The much larger inner rod protected the fiber coating from being stripped when the fiber was withdrawn from the SPME–LC interface. The system was evaluated in term of pressure test, desorption optimization, peak shape, carryovers, linear range, precision, and limit of detection (LOD) with polycyclic aromatic hydrocarbons (PAHs) as the test analytes. The results demonstrated that the improved system was robust and reliable. It overcame the drawbacks, such as leak of solvents and damage of fiber coatings, associated with current SPME fibers and SPME–LC interface. Another sealing mechanism was proposed by sealing the nitinol rod with a specially designed poly(ether ether ketone) (PEEK) fitting. The device was fabricated and tested for manual use. 相似文献
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WEI Wei LI Xu-wen SHI Xiao-lei ZHOU Hong-yu YANG Rui-jie ZHANG Han-qi JIN Yong-ri College of Chemistry Jilin University Changchun P. R. China 《高等学校化学研究》2011,27(1):23-27
Matrix solid-phase dispersion(MSPD) was developed for the extraction of four alkaloids, including aconitine, mesaconitine, hypaconitine and deoxyaconitine, from the roots of Aconitum kusnezoffii Reichb. The determination of the analyte was carried out by high performance liquid chromatography with UV detection. The alkaline alumina was used as sorbent. The mixture of acetonitrile and water was used as elution solvent. Several extraction parameters, such as type of sorbent, the ratio of sample to solid suppo... 相似文献
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静电场诱导十二烷基硫酸钠结晶行为的研究 总被引:4,自引:0,他引:4
用透射电镜、X射线衍射及DSC等方法 十二烷基硫酸钠(SDS)极稀水溶液(溶液介于临界聚集浓度和临界胶束浓度之间)在静电场作用下的结晶行为,静电场作用诱导SDS形成规则的四方单晶与从甲醇中重结晶所得样品的晶体结构相同,DSC结果表明,从有序到无序结构变化的一级相转变热焓相同,但由于电场诱导结晶的晶体较小而表现为转变温度的降低,没有施加静电场处理的样品只具有较低的有序程度。 相似文献
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离子注入Pt的玻碳电极上甲酸和甲醛的电氧化 总被引:3,自引:0,他引:3
制备了离子注入Pt的玻碳电极(Pt/GC),注入剂量为5×1017ion/cm2,此电极的表面组成和各元素的浓度-深度分布用AES测量,注入Pt的价态用XPS测量.在0.5mol/LHClO4溶液中,用Pt/GC电极和纯Pt电极研究了甲酸的电氧化行为,并在五种不同种类的电解质溶液中研究了甲醛的电氧化行为.结果表明,Pt/GC电极对甲酸和甲醛的电催化性能按真实表面积计算优于纯Pt电极.这可能与离子注入Pt过程中形成纳米团簇有关.此外,在同一电极上,甲醛在不同种类的电解质溶液中产生不同的氧化电流.说明阴离子对甲醛的电氧化过程有明显影响 相似文献
50.
Faezeh Pourebrahim Mehrorang Ghaedi Kheibar Dashtian Shadi Kheirandish Alireza Goudarzi 《应用有机金属化学》2018,32(3)
Simultaneous preconcentration and determination of auramine o (AO) and crystal violet (CV) dyes from aqueous solution was conducted by ultrasound assisted (dispersive) solid phase microextraction (UASPME) based on SnO2/SnS composite loaded activated carbon (SnO2/SnS‐NCs‐AC). The prepared of SnO2/SnS‐NCs‐AC was characterized by FESEM and XRD analysis. Main and interaction influences of operational parameters such as pH, sonication time, amounts of sorbent, and type of eluent on extraction efficiency were investigated by central composite design and optimized with desirability function approach (DFA). ANOVA was conducted and shows that optimized values were found at 15.33 min sonication time, 0.019 g SnO2/SnS‐NCs‐AC mass, pH 5.46 and among different solvents, dimethyl formamide was selected as an efficient eluent. Under this conditions recoverees percentage were obtained 82.85% and 86.70% for AO and CV, respectively. Based on F‐test under ANOVA all main effect and interaction effect of understudy parameters has the significant effect on the responses. At optimum conditions, limit of detection (0.0015 and 0.001 mg/l), limit of quantitation (0.4 and 0.4 mg/l), limit of linearity (9.0 and 9.0 mg/l), enrichment factor (33.48 and 83.71) and percent relative standard deviation (3.44 and 4.20) were found to be for auramine o and crystal violet dyes, respectively. Finally, the method was successfully applied for the preconcentration and determination of AO and CV in water samples and ER% of 89.0‐97.0 and 96.2–98.0% as acceptable range were found to be for AO and CV samples, respectively. 相似文献