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1.
《Analytical letters》2012,45(4):175-183
Abstract A study has been made of the method used for extracting the complex formed between thallium(III) and PhMBP. It has been demonstrated that thallium(III) can be readily extracted as a complex with PhMBP by organic solvents at low pH. The extraction of thallium(III) has been studied as a function of pH, concentration of reagent, nature of solvent, duration of contact of the phases and concentration of thallium(III). It has been established that thallium(III) forms a complex with PhMBP of the type MAn, where n=3. The stability constants and distribution constant of the neutral complex has been calculated by the method of Leden-Rydberg. 相似文献
2.
A selective method has been developed for extraction chromatographic studies of aluminium(III) and its separation from several metal ions with a chromatographic column containing N-n-octylaniline (liquid anion exchanger) coated on silanized silica gel as a stationary phase. The aluminium(III) was quantitatively extracted with the 0.065 mol/L N-n-octylaninine from 0.013 to 0.05 mol/L sodium succinate at a flow rate of 1.0 mL/min. The extracted metal ion has been recovered by eluting with 25.0 mL of 0.05 mol/L hydrochloric acid and estimated spectrophotometrically with aurintricarboxylic acid. The effects of the acid concentration, the reagent concentration, the flow rate and the eluting agents have been investigated. The log-log plots of distribution coefficient (KdAl(III)) versus N-n-octylaniline concentrationin 0.005 and 0.007 mol/L sodium succinate gave theslopes 0.5 and 0.7 respectively and showed theprobable composition of theextracted species was 1:1 (metal to amine ratio) and the nature of extracted species is [RR''NH2+ Al succinate2-] org. .The extraction of aluminium(III) was carried out in the presence of various ions to ascertain the tolerance limit of individual ions. Aluminium(III) has been separated from multicomponent mixtures, pharmaceutical samples and synthetic mixtures corresponding to alloys. A scheme for mutual separation of aluminium(III), indium(III), gallium(III) and thallium(III) has been developed by using suitable masking agents. The method is fast, accurate and precise. 相似文献
3.
Thallium(I) bis-oxalatodiaquaindate(III) monohydrate was obtained by precipitation of indium(III) withoxalic acid from slightly
acidic solution in the presence of thallium(I). The complex was subjected to chemical analysis. The thermal decomposition
behavior of the complex was studied using TG, DTA and DTG techniques. The solid complex salt and the intermediate product
of its thermal decomposition were characterized using IR absorption and X-ray diffraction spectra. Based on data from these
physicochemical investigations the structural formula of the complex was proposed as Tl[In (C2O4)2 (H2O)2]⋅H2O.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
4.
Syed Najmul Hejaz Azmi Bashir Iqbal Muna Ahmed Mohad Jaboob Warda Ali Said Al Shahari Nafisur Rahman 《中国化学会会志》2009,56(6):1083-1091
The objective of this work is to develop and validate spectrophotometric method for the determination of piroxicam in commercial dosage forms. The method is based on the chelation of the drug with Fe(III) to form pink coloured metal chelate at room temperature which absorbs maximally at 504 nm. Beer's law is obeyed over the concentration range of 8–160 μg mL?1 (A = 1.07 × 10?3 + 7.75 × 10?3 C). Under the optimized experimental conditions, proposed method is validated as per the International Conference on Harmonisation guidelines. The limits of detection and quantitation for the proposed method are 0.775 and 2.348 μg mL?1, respectively. The proposed method has been successfully applied to the determination of piroxicam in commercial dosage forms. The results are compared with the reference El‐Ries et al. spectrophotometric method. 相似文献
5.
石墨炉原子吸收法测定生物样品中的铊 总被引:1,自引:0,他引:1
为建立测定生物样品中铊的石墨炉原子吸收法,通过微波消解,采用基本改进剂,改变石墨炉灰化温度等操作条件,提高了该法的准确度和精密度.结果表明,方法的线性范围为0~100 μg/L;检出限:血为0.10 mg/L;尿为0.02 mg/L;头发为0.20 mg/kg;回收率:血为83.1%~108%;尿为89.6%~105%... 相似文献
6.
目的 为了查明可溶性有机质(DOM)对土壤中污染元素铊赋存形态的影响,方法 采用形态分级提取方法,将土壤中的铊重金属分成酸可交换态、铁锰氧化物结合态、有机质结合态和残留态4组分,并采用Elan 6100型ICP-MS质谱仪测定各组分中铊的质量浓度.结果 DOM可降低酸可交换态的Tl,增加铁锰氧化物结合态和有机质结合态Tl的百分含量,但对残留态Tl的百分含量没有明显影响.因此,DOM可降低铊在土壤中的活动性,从而改变了铊在土壤中的迁移行为.结论 可溶性有机质(DOM)自身的络合(螯合)能力及其吸附特性是改变重金属铊形态分布的主要因素. 相似文献
7.
《Analytical letters》2012,45(2):469-479
Abstract A method for the determination of thallium in solid environmental samples is developed. After destruction of the sample, TI(III) is extracted from 0.5 M hydrobromic acid solution into diisopropyl-ether. the organic phase is evaporated and the residue taken up in a mixture of sulfuric and nitric acids. Measurements are carried out with an atomic absorption spectrometer with Zeeman background corrector. the accuracy of the method is tested by analysis of certified reference materials and the method is applied to fly ash and emitted particulate matter from a municipal refuse incinerator and to soil samples. 相似文献
8.
在0.08 mol/L氢溴酸介质中,Tl Br4–和甲基绿形成稳定的蓝紫色缔合物,该缔合物被乙酸异戊脂萃取后用分光光度法测定高氯废水中的铊。在最佳吸收波长590 nm处,铊的质量浓度在0~5μg/(10 mL)范围内与吸光度呈良好的线性关系,相关系数为0.998 7,检出限为0.005 3μg/mL。测定结果的相对标准偏差为1.99%~3.38%(n=6),样品加标回收率为96.55%~98.04%。该方法操作简单,可应用于高氯废水中铊的测定。 相似文献
9.
Thallium(III), in the presence of other triply charged ions such as gallium, indium, bismuth and antimony in aqueous solution, was quantitatively and selectively extracted into 2-propanol/water phase by addition of NaCl ranging from 2.5 to 4.0 mol dm−3. The extraction efficiencies of gallium, indium, bismuth and antimony were much lower than that of thallium(III). Thus a maximal selective separation of thallium(III) from these elements could be attained using a 2-propanol/water mixture. Thallium(III) was extracted as TlCl4− with Na+. The detailed extraction mechanism in the presence of chloride, water in the organic phase and counter ions is discussed. 相似文献
10.
采用HCl-HNO_3-HF-HClO_4四种酸溶解铅锌精矿样品,稀释后用电感耦合等离子体原子发射光谱(ICP-AES)法测定其中的铊元素,测定范围0.005%~0.05%。实验确定了介质酸浓度、干扰元素的校正方法。方法相对标准偏差(n=7)为1.3%~4.8%,加标回收率为93.7%~102%,方法干扰少、快速、结果准确,适用于大批量铅锌精矿样品中铊的测定。 相似文献
11.
孙丽丽 《中国无机分析化学》2018,8(5):14-17
通过对观测方式、测定波长、共存元素干扰等因素进行分析和条件优化,建立了测定磷酸一铵、磷酸二铵中铊含量的碘化钾-甲基异丁基甲酮(KI-MIBK)萃取电感耦合等离子体发射光谱法。实验表明,直接采用电感耦合等离子体发射光谱法进行测定时,磷酸一铵、磷酸二铵中的锰元素对分析结果有正干扰。通过萃取分离,干扰被排除,测定结果准确、可靠。在0~1.0 mg/L范围内,铊的质量浓度与光谱强度呈良好的线性关系,相关系数达1.0000。该方法检出限为0.0072 mg/kg,相对标准偏差为4.28%(n = 10),加标回收率在97.00%~100.5%之间。 相似文献
12.
A. Chylewska D. Jacewicz D. Zarzeczaska L. Chmurzyski 《The Journal of chemical thermodynamics》2008,40(8):1290-1294
The acid–base properties of analogous complex ions of chromium(III) and cobalt(III) in aqueous solution have been studied. The equilibrium constants for all metal complexes were determined by using potentiometric and spectrophotometric titration methods. First, dissociation constants for the studied complexes of Cr(III) and Co(III) were determined by means of the potentiometric titration method and using the STOICHIO computer programme. Then, pH-spectrophotometric titrations were performed and the OriginPro 7.5 computer programme was used to calculate the same constants. The measurements using both methods were carried out under the same conditions of temperature, T = 298.15 K, and over the same pH range 2.00–10.00, respectively. It turned out that the two methods used enabled us to obtain acidity constants in very good agreement. 相似文献
13.
Nano-TiO2 was employed for the separation and preconcentration of thallium.It was found that the adsorption ratio of thallium ions was more than 98% at pH 4.5 and the desorption ratio reached 99% under microwave irradiation for 3 min at 350 W.The adsorption equilibrium was well described by the Langmuir isotherm model with a maximum adsorption capacity of 4.09 mg/g[(20±0.1) °C].The nano-TiO2 was successfully applied to the determination of element thallium in the certified reference material polymetallic nodule and water samples. 相似文献
14.
研究了微分脉冲伏安法测定复杂硫酸锌溶液体系中的铊。讨论了伏安图的形成、测定底液和pH值的选择。结果表明:在醋酸介质(pH=4.5±0.2)中,加入适量EDTA、聚乙二醇6000和抗坏血酸的测定体系,采用微分脉冲伏安法可直接测定铊。方法检出限为1.0×10-8g/L,千倍浓度的8种阳离子共存或单独存在时均不干扰测定。方法用于湿法炼锌中上清、一段净化后液、二段净化后液、电积新液、电积废液中铊的测定,相对标准偏差RSD分别为1.6%,2.5%,3.3%,8.3%,4.9%,铊加标回收率为98.4%~102.2%。方法灵敏、简单、快速,用来测定湿法炼锌各阶段硫酸锌溶液中的铊,结果满意。 相似文献
15.
A new route for the synthesis of ipriflavone, an antiosteoporotic agent, is described that has four steps and 60% yields starting from resacetophenone (2). The key step of the present methodology is thallium(III) p-tosylate mediated oxidative 2,3-aryl rearrangement of flavanone to generate the isoflavone ring system of ipriflavone in a highly efficient manner. 相似文献
16.
建立了一种以聚氨酯泡沫富集-电感耦合等离子体原子发射光谱法(ICP-AES)测定土壤及水系沉积物中铊含量的分析方法,利用正交实验,确定最佳实验条件,方法的检出限为0.01mg/L,对土壤及水系沉积物标准物质的测定结果与推荐值相符,相对误差小于10%,相对标准偏差(RSD,n=10)在1.9%~4.9%。 相似文献
17.
Ramakant Rastogi Hemakant R. Mhatre Murlidhar A. Mahajan Nirmal K. Chaudhuri Surgounda K. Patil 《Mikrochimica acta》1991,103(1-2):45-52
A spectrophotometric method for the determination of trace amounts of fluoride in aqueous solution is developed. It is based on the back extraction of Zr(IV) from its thenoyltrifluoroacetonate complex in benzene by aqueous F– followed by the development of Zr-arsenazo(III) coloured complex and the measurement of the absorbance at 665 nm. Optimum conditions and effect of interfering ions are studied. The coefficients of variation obtained are 1.5% and 2.2% in 11 determination at the F– concentration level of 10.0 g/ml and 1.6 g/ml. An excess of Al(III) is used for decomplexing Zr-fluoride prior to the colour formation if the fluoride amount is high. The method is useful for the determination of trace impurities of fluoride in nuclear fuel after separating fluoride from fuel matrix by pyrohydrolysis. 相似文献
18.
Ján Medved’ Milan Kališ Ingrid Hagarová Peter Matúš Marek Bujdoš Jana Kubová 《Chemical Papers》2008,62(2):168-175
Determination of thallium in polluted environmental samples and their extracts obtained by a modified BCR three-step sequential
extraction procedure was used to study thallium distribution and mobility in the monitored polluted area affected by acidification
(Šobov, Central Slovakia). The results of fractionation applied to 5 soil certified reference materials and 14 environmental
samples show that the vast majority of thallium occurred in the residual fraction. This means that highly toxic thallium is
strongly entrapped in the parent rock materials remains immobile and its environmental toxicity is therefore reduced. The
limit of detection for thallium in the studied fractions was lower than 0.050 mg kg−1, the precision (RSD) of the ultratrace determination of thallium in the studied fractions was better than 17 % and the accuracy
of the used method was verified by analyzing certified reference materials.
Presented at the XVIIIth Slovak Spectroscopic Conference, Spišská Nová Ves, 15–18 October 2006. 相似文献
19.
20.
《Analytical letters》2012,45(16):2996-3005
Abstract A effective and simple determination of poisonous trace element thallium(I) by means of kinetic catalytic reaction is proposed. The method is based on a catalytic effect of thallium(I) on a luminol-hydrogen peroxide system. Three different kinds of surfactants, cetrimonium bromide (CTMAB), sodium dodecyl sulphate (SDS), and Tween-80, are also investigated to improve the detection sensitivity. In optimum conditions, a highly selective and sensitive method for detecting trace thallium(I) has been established. The detection limit is 0.0073 µg · mL?1, the relative standard deviation for six determinations of 0.04 µg · mL?1 thallium(I) is less than 4.0%, and the linear range of determination is 0.02–0.1 µg · mL?1. 相似文献