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氢化物原子荧光光谱法测定虾中砷和汞 总被引:1,自引:0,他引:1
建立了氢化物原子荧光法同时测定虾中砷和汞的方法。研究了样品前处理及实验条件对测定砷、汞的原子荧光强度的影响,并探讨了共存离子对测定砷、汞的干扰和消除的方法。本方法具有操作简便、快速、灵敏度高等优点,砷和汞的检出限分别为0.026μg/L和0.020μg/L;相对标准偏差分别为1.7%~9.4%和1.2%~9.4%;回收率为98%~106%。 相似文献
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HPLC-ICP-MS测定中药中砷的形态 总被引:2,自引:1,他引:2
报道了高效液相色谱-电感耦合等离子体质谱(HPLC—ICP-MS)联用技术测定中药中砷的形态,采用阴离子交换柱,以0.2mmol/L EDTA和2mmol/L NaH2PO4的溶液为流动相,pH6.0,流速为1.0mL/min,成功分离了亚砷酸(AsⅢ)、砷酸(AsV)、甲基砷(MMA)和二甲基砷(DMA)。检出限分别为0.67μg/L(AsⅢ),0.85μg/L(DMA),0.43μg/L(MMA),0.70μg/L(AsV)。中药样品经过(1+1)甲醇和水的溶液超声提取,离心、过滤、氮气吹干甲醇,超纯水定容。样品加标平均萃取回收率分别为:92.8%(AsⅢ),108%(DMA),104%(MMA),101%(AsV),相对标准偏差(RsD,n=7)均小于10%。 相似文献
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活性氧化铝微柱分离富集-电感耦合等离子体原子发射光谱法在线测定水中铬(Ⅲ)和铬(Ⅵ) 总被引:7,自引:0,他引:7
研究了活性氧化铝对Cr(Ⅲ)和Cr(Ⅵ)分离富集的性能,建立了流动注射(FI)-在线微柱分离富集-电感耦合等离子体原子发射光谱(ICP-AES)法测定水中微量Cr(Ⅲ)和Cr(Ⅵ)的分析方法。优化了流动注射测定的条件,进样频率为60/h;检出限(3σ):Cr(Ⅲ)为0.8μg/L,Cr(Ⅵ)为0.6μg/L;线性范围为5-600μg/L;相对标准偏差小于2.4%;回收率为94.0%-102%。 相似文献
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Yoon-Young Chang Seung-Mok Lee Jae-Kyu Yang 《Colloids and surfaces. A, Physicochemical and engineering aspects》2009,346(1-3):202-207
The removal properties of As(III) and As(V) by the several metal oxides having different mineral type and content of metals were investigated in batch and column reactors. The used metal oxides were Fe-oxide loaded sand (ILS), Mn-oxide loaded sand (MLS), activated alumina (AA), sericite (SC) and iron sand (IS). From the pH-edge adsorption experiments with AA and ILS, maximum As(III) adsorption was observed around neutral pH while As(V) adsorption was followed an anionic-type behavior. Among five metal oxides, AA showed the greatest removal capacity for both As(III) and As(V) through adsoption process but it has little oxidation capacity for As(III). Eventhough IS had much greater content of Fe-oxides than ILS, it showed a relatively lower removal capacity for both As(III) and As(V). This result suggests that adsorption of arsenic onto metal oxides is controlled by not only the contents of Fe-oxides but also mineral type of Fe-oxides. Column tests were performed at different combinations of metal oxides in a column reactor to find the best column system, which effectively treat both As(III) and As(V) at the same time. Among several combinations, the column reactors packed with MLS-AA and MLS-ILS showed a near complete oxidation of As(III) by MLS for a long time and the greatest adsorption of total arsenic compared to the column reactor packed with MLS-IS. 相似文献
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A natural biosorbent containing amine functional groups, chitosan, and a novel sorbent, chitosan-immobilized sodium silicate, were prepared and utilized for the selective sorption of As(V) from waters prior to its determination by atomic spectrometric techniques, namely, hydride generation atomic absorption spectrometry (HGAAS) and inductively coupled plasma mass spectrometry (ICP-MS). Chitosan was synthesized from chitin and sodium silicate was used as the immobilization matrix due to its straightforward synthesis. Through sequential sorption studies, it was shown that chitosan-immobilized sodium silicate has exhibited a better chemical stability than the chitosan itself which demonstrates the advantage of immobilization method. Both chitosan and chitosan-immobilized sodium silicate were shown to selectively adsorb As(V), arsenate, from waters at pH 3.0 at which neither chitin nor sodium silicate displayed any sorption towards As(V). The sorption of arsenate by chitosan is supposed to have electrostatic nature since pH of 3.0 is both the point at which the amino groups in chitosan are protonated and also the predominant form of As(V) is H2AsO4−. A pre-oxidation step is required if both As(III) and As(V) are to be determined. Desorption from the sorbents was realized with 1.0% (w/v) l-cysteine prepared in a pH 3.0 solution adjusted with HCl. Among the possible interfering species tested, only Te(IV) and Sb(III) were shown to cause a decrease in the sorption capacity especially at high interferant concentrations. High concentrations of Sb(III) also resulted in gas phase interference during hydride generation.The validity of the method was checked both via spike recovery experiments and also through the analysis of a standard reference material. Spike recovery tests were carried out with four different types of water; namely, ultra-pure, bottled drinking, tap, and sea water; and percent recovery values were found to be 114 (±4), 112 (±2), 43 (±4), and 0 (±1), respectively. It was concluded that the proposed methodology can be applied efficiently to low-to-medium ionic strength solutions, such as most drinking waters. The accuracy of the method was additionally investigated through the analysis of a standard reference material and a good correlation was found between the determined (26.6 ± 2.4 μg L−1) and the certified (26.67 μg L−1) value. 相似文献
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Ultraviolet irradiation (photolysis) in alkaline medium was applied for pretreatment of seawater samples so as to accurately determine total As by continuous-flow hydride generation-atomic fluorescence spectrometry. This sample pretreatment is meant to convert non-reducible As forms into inorganic As, which easily forms arsine. The optimised parameters were the treatment time and the pH of the medium. The behaviour of four hydride-reactive As species [As(III), As(V), MMA, DMA], and AsB, i.e. a typical non-hydride-reactive As species, when subjected to UV irradiation was studied. UV irradiation at pH 1 lead to conversion of all species into As(V) with the exception of AsB and DMA. Conversions of DMA and AsB into As(V) at pH 11 in less than 30 min were observed under UV irradiation. The limit of detection of As (measured as As(V)) by hydride generation-atomic fluorescence spectrometry was 0.1 μg/L and the repeatability of the oxidation procedure was about 10%. The method was applied to determination of total and directly reducible As at 11 sampling points of the Galician Coast (Atlantic Ocean, Spain). Total As concentrations were in the range 1.4-4.8 μg/L. A significant As fraction, between 20 and 44%, depending on the sampling point, corresponded to non-reducible As which was converted by UV irradiation into hydride-reactive As. This fraction should represent the sum of DMA, which yields a low sensitivity in the continuous flow-AFS system, and the hidden As fraction. 相似文献
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On Formation of Arsenatephosphates Pb[H2(As, P)O4]2 and PbH(As, P)O4 and the Distribution of As and P at the Anion Positions in Pb[H2(As, P)O4]2 Arsenatephosphates Pb[H2(As, P)O4]2 and PbH(As, P)O4 were prepared and characterized by chemical analysis and X-ray investigations. The observed linear dependence between unit cell parameters and the As/P-contents points to the existence of a complete range of mixed crystals as well between Pb(H2PO4)2 and Pb(H2AsO4)2 as between PbHPO4 and PbHAsO4. The occupation of the anion sites in Pb[H2(As, P)O4]2 by AsO4 and PO4 has been determined by X-ray structure analysis. The calculated occupation factors and the mean bond distances in the anions of the two sites showed, that there exists a slight preference for As to go into site P, As(1). 相似文献
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Differential Alternative Pulses Voltammetry (DAPV), introduced by the authors earlier, was applied with HMDE for direct As(III) determination in the presence of Pb(II) in natural water without sample pretreatment. Distinguishable peaks of As(III) and Pb(II) were registered in 1 M HCl supporting electrolyte at a concentration ratio as high as 1 : 6, while complete peak overlapping occurs applying DPP at any concentration ratio at the same experimental conditions. In‐situ As(III) determinations in the presence of Pb(II) in contaminated ground waters in Mexico were performed, using especially designed disposable safe mercury drop electrodes. 相似文献
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Polyphenylene sulfide‐based adsorption resins: synthesis,characterization and adsorption performance for Hg(II) and As(V) 下载免费PDF全文
A series of novel adsorption resins were synthesized via the chloromethylation of polyphenylene sulfide (PPS) resin and subsequent functional group conversion reaction. Their chemical structure, thermal stability, and morphology were systematically characterized by the Fourier transform infrared spectroscopy, elemental analysis, Raman spectroscopy, thermogravimetric analysis, scanning electron microscope, and energy dispersive spectrometer, respectively. The experimental results showed that the thioureido, mercapto, aminopyridine, and quaternary ammonium groups had been respectively introduced into PPS matrix, the functional group content of PPS‐based mercapto resin (HS‐PPS), aminopyridine resin (AP‐PPS), and quaternary ammonium resin (QA‐PPS) were about 2.20, 1.71, and 2.61 mmol g?1, respectively. The adsorptive performance for Hg (II) and As (V) were studied by batch adsorptive method; the adsorption capacities of the HS‐PPS and AP‐PPS resin for Hg (II) were 210.65 and 169.06 mg g?1. The adsorption capacity of the QA‐PPS resin was 88 mg g?1 for As (V). Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
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《Analytical letters》2012,45(16):3002-3013
Abstract In this paper a disposable gold screen‐printed working electrode was tested for arsenic detection in aqueous solutions using Square Wave Anodic Stripping Voltammetry (SWASV). The dynamic range of the sensor and its response were characterised in standard As(III) solutions; particular efforts were devoted to optimize electrode surface conditioning and electrolyte solution composition. The detection limit was 2.5 µg l?1 using 60 s as deposition time. A portable battery‐operated device was used to demonstrate the possibility to use the sensor for on‐site analysis. Analysis of spiked samples was also performed. 相似文献
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《Electroanalysis》2006,18(18):1763-1770
Poly(L ‐lactide) stabilized gold nanoparticles (designated as PLA–AuNP) with an average particle size of ca. 10 nm were used to modify a disposable screen‐printed carbon electrode (SPE) for the detection of As(III) by differential pulse anodic stripping voltammetry. Gold modification was evaluated by cyclic voltammetry, whereas scanning electron microscopy and transmission electron microscopy revealed the size and distribution of gold nanoparticles. The PLA–AuNP/SPE was applied effectively to detect toxic As(III) in HCl medium. Under the optimal experimental conditions, a linear calibration curve up to 4 ppm with a detection limit (S/N=3) of 0.09 ppb was obtained. The sensitivity was good enough to detect As(III) at levels lower than the current EPA standard (10 ppb). Most importantly, the PLA–AuNP/SPE can be tolerable from the interference of Cu, Cd, Fe, Zn, Mn, and Ni and hence provides a direct and selective detection method for As(III) in natural waters. Practical utility of the PLA–AuNP/SPE was demonstrated to detect As(III) in “Blackfoot” disease endemic village groundwater from southwestern coast area of Taiwan (Pei‐Men). 相似文献
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测定了70例皮肤接触砷(As)引起中毒症状的患者血清砷、谷丙转氨酶(ALT)、白细胞总数(WBC)及分类(DC)计数,结果显示患者除出现严重皮肤溃烂的临床症状外,血中嗜中性粒细胞明显增高,均值高于正常对照组,P〈0.01;血清砷含量均值为0.42μmol/L,显著高于正常对照组(x↑-〈0.01μmol/L),P〈0.01。说明人体皮肤对砷有很强的吸收能力,应尽量防止皮肤接触引起的类似中毒事件发生 相似文献