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51.
A powdered sample of Phyllanthus amarus herb of Kadapa district of Andhra Pradesh, India, is used in the present study. ICP-MS analysis indicates that copper is present in higher concentration when compared to other elements. Although the Pb is toxic, it is within the permissible limit. The evaluated soil and herb physico-chemical parameters indicate that the sample is acidic in nature in comparison with the soil. An EPR study on powdered sample confirms the presence of Fe(III), Mn(II) and Cu(II). Optical absorption spectrum indicates that Fe(III) impurity is present in octahedral structure whereas Cu(II) is present in rhombically distorted octahedral environment. MIR results are due to carbonate fundamentals.  相似文献   
52.
The diagnosis of affective disorders has been the subject of constant research by clinicians from all over the world for many years. Making an appropriate diagnosis among patients suffering from mood disorders is sometimes problematic due to the personality-changing nature of patients and the similarity in the clinical picture of episodes in affective disorders. For this reason, there is a need to develop rapid and effective methods of determining biological markers that differentiate these diseases. The research was carried out with blood taken from 15 patients and 15 volunteers. The analysis of biological material for trace concentrations of zinc and copper was carried out with the use of ultrasensitive triple-quadrupole inductively coupled plasma mass spectrometry (TQ ICP-MS). The obtained results prove that the concentration of copper in the test group was lower than in the control group. For the zinc concentrations, the inverse relationship was observed. The group of patients was characterized by a higher concentration of this element than the group of healthy volunteers. Summarizing the obtained results and comparing them with the results of studies by other authors, it was found that zinc and copper may be potential biomarkers of affective disorders and pandemic syndrome.  相似文献   
53.
This paper presents size exclusion chromatography data with on-line coupling to UV and inductively coupled plasma mass spectrometry (ICP-MS) of water soluble metal-binding compounds present in zinc, copper, chromium and iodine enriched yeast nutritional supplements. Molecular weight estimates of the extracted metal-containing compounds are given and are shown to vary substantially from 1.2 kDa to larger than 668 kDa. Seven proteins suspected of containing chromium were identified from one of the chromium-containing fractions. Four of these identified proteins are known to form complexes with other metal ions. The metal chromatographic profiles of zinc, copper and chromium-enriched yeasts were compared to their respective native metal profiles in non-enriched yeast samples. The chromium profiles are shown to be markedly different while those of zinc and copper are qualitatively similar. Only iodide ions or weakly bound, non-aromatic, low molecular weight ( 1.2 kDa) iodine species were observed in the iodine-enriched yeast samples.  相似文献   
54.
Dynamic information is generally extracted from deuterium quadrupole echo spectra by matching a spectrum calculated for a particular motional model to the experimental spectrum. In this work, a set of computer programs has been written to facilitate fitting of calculated spectra to experimental spectra that represent from one to five motional models. The fitting program requires pre-calculated libraries of spectra for the models of interest, and accomplishes the fitting either by a systematic method or by simulated annealing. The systematic method is convenient for fitting with one or two motional models, but the simulated annealing method is faster for two or more models, if the libraries are made up of hundreds of spectra. The parameter Q, with the standard deviation of the spectral points estimated as the standard deviation of the baseline noise, provides a stringent measure of goodness of fit. Acceptable fits of experimental data as judged by this criterion have not been found, even in the case of ring flip motion in phenylalanine-d(5) in which the fit may be judged acceptable by eye. An example of fitting with isotropic and methyl rotation motional models of alanine-d(3), which have distinct spectral patterns, shows that it is possible to obtain reasonably accurate estimates of the relative amounts of deuterium representing the different models, even from poorly fitted spectra.  相似文献   
55.
姚曦  岳永德  汤锋  郭雪峰  王进  荀航 《光谱实验室》2010,27(3):1190-1194
建立同时检测鲜竹笋中铬、铜、锌、砷、镉、汞、铅等7种元素的分析方法。竹笋样品在硝酸介质中经微波消解,用电感耦合等离子体质谱(ICP-MS)检测,全定量法采集数据。校准曲线线性良好,相关系数在0.9937—1.0000之间;检出限为0.005—0.202μg/L;加标回收率在88.96%—110.5%;精密度RSD小于6.09%;国家标准样品西红柿叶(GSBZ51001-94)中几种元素的测定值都在标准范围内。该方法具有灵敏、可靠、快速、准确等优点,适用于竹笋中微量元素的分析测定。  相似文献   
56.
Cross-linked chitosan was chemically modified with di-2-propanolamine via an arm of chloromethyloxirane (CCTS-DPA resin). The adsorption behavior of the resin towards 62 elements was examined using a mini-column pretreatment method, and the collected elements were eluted with 1 mol L− 1 nitric acid before measurement by inductively coupled plasma-mass spectrometry (ICP-MS).The CCTS-DPA resin can adsorb several metal cations and several oxoanionic elements at appropriate pH. However, di-2-propanolamine (DPA) attached to cross-linked chitosan (CCTS) showed excellent ability and selectivity for the adsorption of germanium at pH 6 to 9. The adsorption capacity of the resin for germanium (IV) was found to be 106 mg g− 1 resin, whereas the adsorption rate constant was 9.82 × 10− 2 min− 1. Through the column treatment, alkali and alkaline earth matrices in river water and seawater matrices could be completely removed. The resin can also successfully remove chloride and selenium that can interfere with the direct determination of germanium by ICP-MS. The applicability of the CCTS-DPA resin was further demonstrated for the collection/preconcentration of germanium in environmental water samples and its determination by ICP-MS. The concentrations of germanium in tap water, river water and seawater samples were found in the range of 0.011 to 0.022 μg L− 1.  相似文献   
57.
The determination of seven arsenic species in seafood was performed using ion exchange chromatography on an IonPac AS7 column with inductively coupled plasma mass spectrometry detection after microwave assisted extraction. The effect of five parameters on arsenic extraction recoveries was evaluated in certified reference materials. The recoveries of total arsenic and of arsenic species with the two best extraction media (100% H2O and 80% aqueous MeOH) were generally similar in the five seafood certified reference materials considered. However, because MeOH co-elutes with arsenite, which would result in a positively biased arsenite concentration, the 100% H2O extraction conditions were selected for validation of the method. Figures of merit (linearity, LOQs (0.019-0.075 mg As kg−1), specificity, trueness (with recoveries between 82% (As(III)) and 104% (As(V) based on spikes or certified concentrations), repeatability (3-14%), and intermediate precision reproducibility (9-16%) of the proposed method were satisfactory for the determination of arsenite, monomethylarsonic acid, dimethylarsinic acid, arsenate, arsenobetaine and arsenocholine in fish and shellfish. The performance criteria for trimethylarsine oxide, however, were less satisfactory. The method was then applied to 65 different seafood samples. Arsenobetaine was the main species in all samples. The percentage of inorganic arsenic varied between 0.4-15.8% in shellfish and 0.5-1.9% at the utmost in fish. The main advantage of this method that uses only H2O as an extractant and nitric acid as gradient eluent is its great compatibility with the long-term stability of both IEC separation and ICP-MS detection.  相似文献   
58.
《Analytical letters》2012,45(10):1827-1841
Abstract

The determination of bromine in human serum by inductively coupled plasma-mass spectrometry (ICP-MS) is discussed. Sample preparation was kept as limited as possible: serum samples were only diluted with nitric acid (five- or ten-fold). Indium was added as internal standard. In order to avoid overlap of 40Ar 40Ar with  相似文献   
59.
ICP-MS测定污水中银的含量   总被引:2,自引:0,他引:2  
童成举  刘涛  魏振宏 《光谱实验室》2010,27(5):1844-1846
研究了ICP-MS测定污水中银的含量,其方法检出限为0.05μg/L,方法精密度RSD为1.91%—2.32%,加标回收率为98.0%—102.4%,方法简单、快速。  相似文献   
60.
ICP-OES和ICP-MS测定中日两国大米中27种矿质元素含量   总被引:6,自引:0,他引:6  
收集了16种中国大米和11种日本大米,经过微波消解或干灰化法处理后,采用电感耦合等离子体发射光谱法(ICP-OES)和电感耦合等离子体质谱法(ICP-MS)测定了其中Al,As,B,Ba,Ca,Cd,Co,Cr,Cs,Cu,Fe,Hg,K,Mg,Mn,Mo,Na,Ni,P,Pb,Rb,S,Se,Sr,Tl,V和Zn等27种矿质元素的含量,并用生物标准参考物质大米(GBW10010)评价了分析方法的准确度。研究结果表明,基于碰撞反应池技术(CCT)的ICP-MS能有效降低一些多原子离子对低m/z元素离子计数的干扰;与日本大米相比,中国大米中Al,S,Sr等元素含量显著偏高,而B,Cd,Cs,Mg,Mo,P,Pb,Zn等元素含量显著偏低(P0.05),采用聚类分析(最小方差法)对矿质元素含量进行处理,可正确判别两国大米。另外,还发现大米中Mg和P含量之间存在很强的线性相关性,相关系数高达0.9552。  相似文献   
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