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1.
A novel and greener ultrasonically assisted/modified cloud point extraction procedure for the simultaneous preconcentration of lead and cadmium in serum samples of different types of gallstone patients was developed. The chelates of the under study metals, formerly formed with 8-hydroxyquinoline, were extracted in the micelles of a nonionic surfactant prior to analysis by flame atomic absorption spectrometer (FAAS). After the arrival of the cloud point, the critical micellar mass produced was homogenously dispersed in the aqueous phase with the help of ultrasound energy. The reliability of the developed procedure was tested by relative standard deviation (% RSD), which was found to be <5%. The performance of the proposed procedure was checked by applying to certified reference material and spiking standard in real samples. All the experimental parameters were optimized. The developed procedure of Um-CPE was applied successfully for the analysis of the target heavy metals in serum samples of different types of gallstone patients and referents. The higher levels of the understudy metals were observed in the patients as compared to the referents but the levels of the both metal were found to be considerably higher in patients with pigmented gallstones.  相似文献   

2.
In this research, ferroferric oxide nanoparticles were coated with silicon dioxide and further functionalized with alizarin complexone as the adsorbent of magnetic solid-phase extraction, thus aiming for extraction and preconcentration of heavy metals in Gastrodiae rhizoma samples. The determination of heavy metals was carried out by flame atomic absorption spectrometry. The results showed that the functionalized magnetic nanoparticles demonstrated higher extraction efficiency for copper, lead, and cadmium. The synthesized magnetic sorbents were characterized by transmission electron microscope, X-ray diffraction, and Fourier-transformed infrared spectra. Different parameters influencing the extraction efficiency including the amount of sorbent, sample pH, sorption time, solution volume, elution solvent, and reuse times were optimized. Under the optimal conditions, the method detection limit was 0.18, 0.25, and 0.12 µg/L for copper, lead, and cadmium, respectively. The proposed method was successfully applied to extract copper, lead, and cadmium in Gastrodiae rhizoma samples, and the recoveries of the samples ranged from 90.0 to 102.0% and relative standard deviations (n = 5) were in the range of 1.93–3.82%.  相似文献   

3.
研究原子吸收光谱法在汽车自动变速器故障检测中的创新性应用。通过原子吸收光谱法测定行驶里程分别为10 000~15 000,20 000~26 000,32 000~38 000,43 000~49 000,52 000~58 000km五批奥迪A6自动变速器油液(ATF)中主要金属Fe,Cu,Cr的含量,建立奥迪A6自动变速器不同行驶里程数ATF主要金属含量的数据库。研究发现主要金属含量随着汽车行驶里程数上升而增加,并且其正常含量在两条趋势线之间。测定有故障症状的ATF主要金属含量,并与其数据库数值比对,既可以判断自动变速器的磨损状况,也可以帮助汽车检测维修人员在不解体状态下诊断汽车自动变速器的故障原因,降低汽车维修成本,提高维修质量。  相似文献   

4.
Holmium doped cadmium lead borate glasses were prepared from melting in appropriate proportions of a mixture of CdO, PbO2, H3BO3 and (1–2 mol %) Ho2O3 in the temperature range of 800–850 °C. The density of glass samples was measured using Archimedes Principle. The infrared spectra of the glasses in the range of 400–4000 cm?1 showed their structure systematically. No boroxol ring formation was observed in the structure of these glasses, but the conversion of 3-fold to 4-fold coordination of boron atoms in the structure of glasses was observed. The glass transition studies were done through differential scanning calorimetry. The optical analysis is done by using the Judd–Ofelt theory.  相似文献   

5.
The determination of lead by flame atomic absorption analysis in the presence of Sn and Fe atoms and different matrices such as OH and SO3 was investigated with the objective of understanding the spectral interference processes at the analytical lines 283.31 nm for a wide range of concentration.The radiation trapping factor was interpreted and evaluated assuming Voigt distribution of the atomic and rotational lines in the flame. The radiation trapping factor was increased by increasing the number density (plasma of the absorbing medium is optically thick). In plasma, there is a certain point of equilibrium between the trapping and the escaping of radiation, which is relevant to 50% of absorption.The spectral background interference can cause a variation of the number density at equilibrium point as a result of the degree of overlap with the analytical line.The spectral background interference can be easily avoided by using another resonance absorption line for the analysis. The chemical modification of the matrix is applied to minimize the interference effect. Nitric acid, ammonium nitrate and magnesium nitrate are most commonly recommended as matrix modifiers.  相似文献   

6.
A magnetic hydroxypropyl-β-cyclodextrin-functionalized reduced graphene oxide was synthesized and used as a magnetic solid-phase extraction adsorbent for the enrichment of cadmium from water and food samples before its determination by flame atomic absorption spectrometry. The effects of pH, amount of adsorbent, extraction time, desorption condition, and coexisting ions on the extraction efficiency were investigated and optimized. Under the optimal conditions, the limit of detection was 0.23?µg?L?1 for water samples and 0.015?µg?g?1 for food samples, respectively. The linear range was between 0.50 and 100.0?µg?L?1 with a good correlation coefficient of 0.9986 in water samples, and between 0.050 and 5.0?µg?g?1 with a correlation coefficient of 0.9975 in food samples. The method recoveries for the spiked samples were in the range of 87.5–102.4%, with the relative standard deviations ranging from 4.7% to 6.2% and enrichment factors ranging from 38 to 41, respectively. The adsorbent could be reused over 50 times without a significant change of extraction capability. The established method provides a promising environmentally friendly alternative for the determination of cadmium in complex matrix samples with no need of additional chelating reagents during the extraction process.  相似文献   

7.
通过扫描电镜(SEM)、静态氮吸附(NSA)和红外光谱(FTIR)法对塔卡拉玛干沙漠自然沙粒(简称沙粒)的粒状及其表面结构、比表面积和功能基团进行了分析,以FAAS作为检测手段,动态法研究了沙粒对pb2+的吸附性及其影响因素并优化了吸附条件;将沙粒作为填料制备了5.0 cm×5 mm i.d.预富集分离微柱,将其与FA...  相似文献   

8.
Spectral line interference may occur in atomic absorption spectroscopy, when there is a significant overlap of the emission line profile with the absorption line profiles of any interfering species in the flame. The presence of the spectral interference can cause errors in the measurements of the net absorbance, and in the background correction.Both theoretical calculations and experimental observations reported in this paper provide a remark of this interference effect. It can be concluded from the experimental results, that the spectral interference is located close to the resonance wavelength of the analyte.Two different examples representing various types and degrees of spectral interference are discussed.  相似文献   

9.
建立了以交联羧甲基魔芋葡甘聚糖(CCMKGM)为微柱预富集-GFAAS测定转基因水稻糙米中痕量铅和镉的新方法。考察了溶液的pH值、样品流速和体积、洗脱液的浓度和体积及共存离子干扰等因素对CCMKGM微柱吸附重金属的影响。结果表明:在优化条件下,方法用于富集、测定转基因水稻及亲本糙米中Pb和Cd的检出限分别为0.11和0.002μg.L-1;测定大米标准参考物质中Pb和Cd的含量,结果与标准参考值相吻合。对转基因水稻及亲本糙米进行标准加入回收实验及测定,回收率分别在90%~103%和93%~105%范围。该研究可为转基因水稻中痕量Pb和Cd分析提供技术支持。  相似文献   

10.
萃取—石墨炉原子吸收光谱法测定高纯氧化钐中的铜和铅   总被引:4,自引:0,他引:4  
本文研究了APDC/MIBK萃取-石墨炉原子吸收光谱法测定高纯稀土氧化钐中的铜和铅。详细探讨了测定条件和萃取条件。该法简单,准确和适用。  相似文献   

11.
12.
The mean probability of photon capture Ψ, obtained via an approximation to the complementary escape factor Λ, for calcium and zinc resonance lines at 4226.73 and 2138.56 Å have been determined from their atomic absorption measurements. Calculations are performed for Gaussian, Lorentzian, and Voigt spectral line shapes. Tabulations and graphical plots of the mean probability of photon capture, Ψ, with the optical depth in the center of Doppler profile, τD, and the number density of free atoms in the ground state N, are provided.  相似文献   

13.
原子吸收光谱法(AAS)广泛应用于重金属分析检测领域,优化测试过程的操作条件,进而保障分析结果的稳定性和重现性,直接关系到预期研究目标的有效实现,建立精准的检测方法往往成为科学研究的首要任务。以金盏菊为黄土区Pb/Cd复合污染修复植物,采用湿法消解-AAS法测定金盏菊幼苗体内Pb/Cd含量,分析所得结果初步揭示金盏菊幼苗对Pb/Cd的富集效应。研究发现:湿法消解-AAS法对Pb/Cd的检出限分别为0.104和0.007 mg·L~(-1),Pb/Cd回收率对应于94.33%~110.78%和97.73%~107.50%之间,同一样品重复测定(6次)的相对标准偏差(RSD)波动于4.11%~4.75%(Pb)和1.11%~2.77%(Cd),表明该方法准确度较好,精密度较高。金盏菊幼苗对Pb的富集能力不强,这可能与Pb的电负性、植物生长周期较短及环境因子等因素有关;但在黄土Cd浓度为50 mg·k~(-1)时,金盏菊幼苗对Cd的平均富集量已达到104.85 mg·kg~(-1)。此外,黄土Pb的共存一定程度上促进了金盏菊幼苗对Cd的吸收,其间可能存在协同作用。所建立的分析方法可以对金盏菊幼苗Pb/Cd含量进行有效检测,预期能为后续研究提供技术支持和质量保障。  相似文献   

14.
采用悬浮液-自吸扣背景石墨炉原子吸收法测定了高纯氧化铝中痕量元素铜、铁、钠含量.实验对灰化温度、原子化温度和自吸扣背景灯电流等石墨炉原子吸收工作条件等进行了优化,确定了最佳测定条件.样品测试采用标准水溶液进行校正,方法准确性采用氧化铝AKP-30在高温高压和浓硫酸密闭条件下溶解样品进样分析测定结果与文献报道的其他测定方...  相似文献   

15.
The spatial distribution of the intensity of radiation from LK-2 two-discharge lamps and LD-2 deuterium and halogen lamps, used in atomic absorption spectrometry, has been investigated. It is shown that the distribution of the intensity of radiation from a two-discharge lamp is saddle-shaped and is determined by the joint action of the process of cathode sputtering and of the processes of excitation and ionization of atoms of the filler element under the conditions of a high concentration of electrons in the positive column of the arc discharge. A dome-shaped distribution of radiation intensity with a maximum on the axis of the discharge is characteristic of deuterium lamps and is determined by the distribution of the concentration of electrons in the positive arc column. For halogen lamps, the intensity distribution in the form of a sharp asymmetric peak is determined by the location and dimensions of the luminescent body made in the form of a spiral. The influence of the spatial characteristics of the radiation from the sources on the error in measuring atomic absorption by a space-integrating recording system has beeb evaluated for different radiation intensity distributions. It is shown that this error is negative and reaches a maximum value for a saddle-shaped distribution of the intensity of transilluminating radiation. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 67, No. 2, pp. 143–147, March–April, 2000.  相似文献   

16.
Abstract

Atomic spectrometry and atomic mass spectrometric (MS) techniques have been playing crucial roles in the field of biosciences. They detect elements with relatively high sensitivities and are thus applicable to a wide range of analytical targets. In the past decade, determination of bio-relevant metallic elements continues to be of interest, while particularly noteworthy are methods developed for small molecules, peptides, proteins, nucleic acids and even cells that well exploited the bio-analytical strengths of atomic spectrometry and atomic MS, either in a direct or indirect manner. Quantitation, as well as speciation and imaging analyses are all involved. The present review aims to assimilate recent advances in bio-analysis utilizing atomic spectrometry and atomic MS, primarily covering the period of 2013–2018, in an attempt to provide readers insight into the developing trends of this research frontier. Followed by concluding remarks and perspectives, the applications are divided into the following four catalogs: (i) toxicologically important metal-containing species, with an emphasis on quantitative and imaging analysis; (ii) quantitation of biomolecules using naturally occurring heteroatoms; (iii) exogenous metal ion or nanoparticle tagging-based strategies in bioassays; and (iv) label-free detection of biomolecules.  相似文献   

17.
A method for verification of analytical measurements in electrothermal atomic absorption spectrometry using a phenomenological model for physicochemical atomization processes is discussed. The influence of the sample matrix on basic kinetic parameters of atomization such as the analyte free-atom formation energy and the atomization rate constant has been shown. The similarity of atomization kinetic parameters obtained by calibrating the spectrometer to those for samples under study can be used as a verification criterion for analysis. __________ Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 75, No. 3, pp. 295–298, May–June, 2008.  相似文献   

18.
We have studied the effect of the nature and concentration of surfactants on the analytical signal of zinc. We show that of all the studied surfactants, sodium dodecylbenzenesulfonate increases the sensitivity and selectivity of the zinc determination the most. We have designed a method for atomic absorption determination of zinc in food products using sodium dodecylsulfate as a modifier. The detection limit for zinc according to the proposed procedure is Cmin = 0.003 μg/mL. Report given at the International Congress of Analytical Sciences, ICAS-2006, 20–30 June 2006, Moscow, Russia. __________ Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 75, No. 2, pp. 269–273, March–April, 2008.  相似文献   

19.
Interest in preconcentration techniques for the determination of metals at ultratrace levels still continues increasingly because of some disadvantages of flameless atomic absorption spectrometry as well as the high costs of other sensitive methods in compared to flame atomic absorption spectrometry.In this study,thiol-containing sulfonamide resin was synthesized,characterized and applied as a new sorption material for solid phase extraction of nickel in drinking water samples.After preconcentration procedure,flame atomic absorption spectrometry was used for determinations.Optimum parameters were found to be pH=3.2,contact time =20 min and eluate volume=3 mL.The limit of detection was found to be 0.75 ng · mL-1.The synthesized resin exhibits the superiority in compared to the other adsorption reagents because of the fact that there is no necessity of any complexing reagent,high sorption capacity as well as the relatively fast extraction rate.The Ni concentrations in the studied 21 kind of water samples were found to be in the range of BDL-4.0 ng ·mL-1.  相似文献   

20.
本文采用双柱富集的在线分离富集系统与 2 2 0FS顺序多元素原子吸收分光光度计联用 ,以PT C18色谱预处理柱为预富集柱 ,二乙基二硫代氨基甲酸钠 (DDTC)和吡咯啶二硫代氨基甲酸铵 (APDC)混合物为螯合剂 ,甲醇为洗脱剂 ,首次实现了Cu ,Pb,Cd ,Co ,Ni,Mn六种元素的快速同时测定。富集倍数为 10 2~ 2 1 7之间。34s富集 (4 4 0mL)的检出限分别为Cu 2 91,Pb 5 81,Cd 0 35 ,Co 3 6 1,Ni4 0 5和Mn 1 94 μg·L-1,相对标准偏差分别为Cu 2 6 4 % ,Pb 2 93% ,Cd 2 5 9% ,Co 2 5 7% ,Ni 2 78%和Mn 3 6 8%。该方法操作简便、快速 ,用于环境样品中痕量元素的测定 ,得到了满意的结果。  相似文献   

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