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1.
Three commercial infant milk formulas, one commercial infant cereal formula and one locally grown cereal used for infant feeding in Nigeria were analyzed for 17 trace elements, viz: Al, As, Br, Ca, Ce, Cl, Co, Cr, Fe, K, Mg, Mn, Na, Rb, Sb, Se and Zn. The commercial milk formulas contain adequate amounts of Ca, Cl, Co, Fe, K, Mg, Mn, Na and Zn, the locally grown cereal contains adequate amounts of Co, K, Mg, Mn and Zn and low in Ca, Cl, Fe and Na while the commercial cereal has adequate amounts of Ca, Cl, Co, K, Mg, Na and Zn. None of the samples analyzed was found to contain any elements up to threshold toxicity limits of concentrations.  相似文献   

2.
The trace element content of the total daily diet (food and beverages) of each of 4 adult males was determined over a period of one week. A method of radiochemical neutron activation analysis is briefly described which enables the determination of up to 31 elements in biological samples. Of the 25 elements determined in the diet 12 are essential elements (Ca, Cl, Co, Cr, Cu, Fe, K, Mn, Mo, Na, Se, Zn) while 6 (As, Ba, Br, Cd, Hg, Sb) are classified as toxic. The average concentrations of the toxic trace elements As, Cd and Hg of the diet are below the provisional tolerable dietary intakes recommended by WHO/FAO. The contents of Cl, Cu, Fe, K, Mn, Na and Zn are adequate to the proposed nutritional requirements.  相似文献   

3.
Instrumental neutron activation was used for the determination of 23 trace and minor elements in 4 different samples of brewer's yeast. Detection limits for these elements vary from 2 ppb to 100 ppm. The following average concentrations were found (ppm, dry weight): Al 597, Br 0.36, Cl 1473, Co 0.21, Cu 19, Fe 285, K 16 400, Mg 1355, Mn 8.4, Na 2330, Rb 19, Sb 0.053, Se 1.2, V 2.2 and Zn 80. NBS standard 1569 was also analyzed and the following concentrations (in ppm) were measured: Al 2300, Br 0.65, Ce 0.23, Cl 460, Co 0.26, Cr 2.12, Cu 11, Fe 707, Gd 7.1, Hf 0.13, K 15 500, Mg 1780, Mn 7, Na 510, Rb 16, Sb 0.075, Sc 0.18, Se 0.92, Th 3.7, Ti 38, U 0.49, V 4.1 and Zn 70.  相似文献   

4.
Concentrations of major and trace elements in volcanic rock and soil samples, including geological standard reference materials, were determined by neutron activation analysis (NAA) and prompt gamma activation analysis (PGAA), both using the k 0-standardization method. The paper highlights the different experimental procedures, such as sample preparation, data collection and spectrum evaluation. In geological samples, PGAA gives precise results for major elements (Si, Ti, Al, Fe, Mn, Mg, Ca, Na, K and—as a unique method—for H), for some of the light trace elements as B and Cl, as well as for Sc, S, Cr, Co, Ni, Cd, Nd, Sm and Gd. NAA is sensitive for the rare earth elements, and for many major (Ti, Al, Fe, Mn, Mg, Ca, Na, K) and trace elements (e.g.: Sc, V, Cr, Co, Ni, Cu, Zn, As, Se, Rb, Sr, Zr, As, Sb, Ce, Ba, Hf, Ta, W). For most major elements the results obtained by the two methods show good agreement. The comparison of the results obtained for trace elements is not always possible, since PGAA is less sensitive and concentrations are often below its detection limits. Nevertheless, the complementarity of NAA and PGAA allows nearly panoramic analysis of geological materials.  相似文献   

5.
Instrumental neutron activation analysis (INAA) with gamma-ray spectrometry was applied to determine As, Ca, Cd, Cl, Co, Cu, Cr, Fe, Hg, K, Mg, Mn, Mo, Na, Sb, Se and Zn in the Brazilian agroindustrial by-products. These materials are widely used in ruminant feeding. The results obtained were compared with requirement and maximum tolerable concentrations. The general conclusions from the data obtained were: (1) many by-products presented concentrations of some essential elements lower than the requirement concentrations, while in some concentrations of Cr, Fe, Mg and Se exceeded by a little the maximum tolerable concentrations, (2) the elements As, Cd, Hg and Sb, generally considered toxic, showed concentrations lower than maximum tolerable values.  相似文献   

6.
Using PIXE (proton induced X-ray emission), PIGE (proton induced gamma emission) and ICP-AES (inductively coupled plasma-atomic emission spectroscopy) the concentrations of the 24 elements Al, As, Ba, Br, Ca, Cl, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Pb, Rb, S, Sb, Si, Sn, Sr, Ti, Zn and Zr in 53 archaeological glass samples from South-Eastern Bulgaria, were determined. The glasses are dated from the 1st to 6th century AD. The analytical data showed the samples to be typical soda-lime-silica glass, with natron as flux. A rather broad range of aluminium, titanium and iron impurities was found, with a tendency for more impure glass in the later periods. The decolouring agents were antimony and manganese oxides, with Sb prevailing in earlier, and Mn in later glass.  相似文献   

7.
The proposed reference material from the International Atomic Energy Agency, namely IAEA-407 (Fish Homogenate) was analyzed using instrumental neutron activation analysis (INAA). 15 elements, Al, As, Cl, Co, Cr, Fe, Hg, Mg, Mn, K, Na, Sb, Se, V and Zn, were determined using two irradiations (5 minutes and 5 hours) and four countings. IAEA-MA-A-1/TM (Copepoda Homogenate), NIST-SRM-1566 (Oyster Tissue), NIST-SRM-1572 (Citrus Leaves) and NIST-SRM-1577a (Bovine Liver) were utilized as standards in the quantification step.  相似文献   

8.
A powdered intercomparison material for trace element studies was prepared from human scalp hair and distributed to more than 100 laboratories of which 66 reported results for altogether more than 40 elements. By statistical evaluation of these data certified concentration values were derived for 20 elements, namely As, Au, Br, Ca, Cd, Cl, Co, Cr, Cu, Fe, Hg, Mg, Mn, Na, Pb, S, Sb, Se, Sr and Zn. The data also made it possible to compare different methods of analysis and to judge the value of different levels of experience on the part of the analyst concerned; these comparisons are presented here with special reference to the elements As, Cd, Hg, Pb and Sb.  相似文献   

9.
Neutron activation analysis (NAA) methods have been developed for the determination of major, minor and trace elements in duplicate diets and individual food items. These include a cyclic instrumental NAA (CINAA) method for measuring Se content through its short-lived nuclide77mSe; epithermal INAA (EINAA) for I and As; conventional INAA for Br, Ca, Cl, Co, Cr, Fe, K, Mg, Mn, Na, Rb, Sb, Sc, Sn and Zn; combination of EINAA and INAA for Al; radiochemical NAA (RNAA) for As, Au, Co, Cu, Fe, Hg, Mo, Sb, Se and Zn; and preconcentration NAA (PNAA) for U and Th. Accuracy of measurements have been evaluated by analyzing a number of biological and diet reference materials. Multielement concentrations of diets and foods have been measured by these methods.  相似文献   

10.
Analyses for certification have been made by instrumental neutron activation analysis (INAA) for the determination of 21 elements in the National Institute of Standards and Technology (NIST) Spinach renewal reference material, SRM 1570a. Elements determined included ones with short halflife products (Al, V, Ca, Mg), intermediate halflife products (Mn, Na, K, La), and long halflife products (Ba, Co, Cr, Cs, Eu, Fe, Rb, Sb, Sc, Se, Sr, Th, and Zn). For the first time a new robotic sample changer was used in the counting of long halflife indicator isotopes for certification of an SRM. Uncertainties obtained averaged±1.80% for the four major and minor constituents (Ca, K, Mg, Na); ±3.14% for elements with concentrations from 1 to 400 mg/kg (Al, Ba, Cr, Fe, Mn, Rb, Sr, and Zn); and±8.31% for the ultra trace elements (<1 mg/kg) (Co, Cs, Eu, La, Sb, Sc, Se, Th, and V).  相似文献   

11.
Four algae reference materials, IAEA-391, 392, 393 and IAEA-140, prepared by the International Atomic Energy Agency for intercomparison under different preparation conditions were analyzed for 24 elements. Conventional neutron activation analysis (NAA) was used to determine Al, Ca, Cl, Co, Cr, Cu, Fe, K, Mg, Mn, Mo, Na, Sb, V and Zn and epithermal NAA using BN and Cd as shielding material for I, Br, As, Ni, Mo and Cd. Inductively coupled plasma mass spectrometry (ICP-MS) as a complementary and comparative method was applied to determine Pb, Sn, Ni, Sr, Rb, As, Co, Cr, Cu, Mn, V, Mo and Zn. Two analytical quality control standard reference materials IAEA-V-10 (hay powder) and IAEA-331 (spinach) were analyzed simultaneously with real samples. The results agree quite well with each other and with the certified values.  相似文献   

12.
The theory and analytical procedures in Instrumental Neutron Activation Analysis (INAA) are discussed. Application of the method to the determination of sixteen trace elements: Na, K, Mn, Sm, La, Fe, Th, Sc, Co, Ba, Rb, Br, Sb, Cs and Ta in some rock samples from Ugep in the Lower Benue Region of Nigeria, is described. The high radioactivity observed in some of the samples analyzed has been associated with the higher-than-normal concentrations of Th and K in the samples. Also, Ba and Fe concentrations in some of the samples were found to be anomalous when compared with average expected values in normal sedimentary rocks.  相似文献   

13.
目的:明确造成前列舒通胶囊不同批次间差异的标志性无机元素,并进行安全性评价。方法:采用ICP-MS测定制剂中Al、As、B、Ba、Ca、Cd、Co、Cr、Cu、Fe、K、Mg、Mn、Mo、Na、Ni、Pb、Sb、Se、Sn、Sr、Ti、Tl、V、Zn和Hg元素含量并进行数据分析。运用主成分及综合评分结合聚类分析手段,确定制剂的特征性元素;进行元素含量和相关性分析,明确不同批次各元素的差异及元素之间的关系;以多元素含量为指标,绘制无机元素谱图。结果:19批样品中均未检测出Se、Mo、Sn、Sb、Tl和Hg,且Pb、Cd、As、Cu、Hg均符合限量标准,无机元素含量谱图趋势一致。主成分分析提取了4个主成分,确定元素B、K、Al、V、Cr、Ca、Ti、Na、Co和Mn可作为特征元素。主成分得分图将19批样品分为两类,聚类分析及综合评分结果与其一致,两类样品中各元素含量存在差异性。相关性分析中,明确了B与K、Al、Cr正相关,K与Cr、Co正相关,V与Cr、Mn正相关,Mn与Co正相关,Ca、Ti、Na两两正相关。结论:通过分析前列舒通胶囊中无机元素含量,确定了特征元素,为前列舒通胶囊质量全面控制研究提供科学依据。  相似文献   

14.
A study was undertaken to assess the air quality of Lahore by the elemental analysis of air conditioner (AC) filter dust samples collected from 15 different commercial sites. Samples were prepared using the Leeds Public Analyst Method and were analyzed using instrumental neutron activation analysis (INAA) for up to 31 elements. The elements Al, As, Ba, Ce, Co, Cr, Cs, Fe, Hf, K, La, Lu, Mn, Na, Nd, Rb, Sc, Sm, Sn, Ta, Th, Yb and Zn were detected in all 15 samples whereas the remaining elements have been detected in fewer samples; i.e. Mg, Sb and Tb were detected in 14 samples, Br and V in ten samples, U in nine samples and Ca and Ti in eight samples only. Al, Ca, Fe, K, Mg and Na were determined in all samples at percentage levels. The concentrations of most elements were found to lie around the mean values for the 15 samples studied and were not orders of magnitude different. However the concentrations of Ca, Mg, Sn and Zn were found to be more variable and were found to be dependant on activities such as construction, fruit and vegetable handling, tin plating and transport, respectively.  相似文献   

15.
Elements Al, As, Au, Br, Cl, Co, Cr, Cu, Fe, Hg, K, La, Mn, Mo, Na, Sb, Sc, Sm, V, and Zn were determined by INAA in several brands and batches of high pressure polyethylene (PE) Bralen (Slovnaft Bratislava, Czechoslovakia). A large scatter of trace element contents was found in both granules and foils, indicating an inhomogeneous distribution for the majority of the above mentioned elements present as impurities in PE. Larger amounts of the elements Al, Mn, and Sb were found in foils than in granules. Blank values resulting from using of PE Bralen as a canning material for INAA were compared to trace element concentration in human hair samples, too.  相似文献   

16.
With the aim of indicating environmental pollution effects by heavy metals on humans using hair, nondestructive activation analysis was applied to 382 normal Japanese hair samples (background level). Elemental contents of hair could be determined for Ag, Al, As, Br, Ca, Cd, Cl, Co, Cr, Cu, Fe, Hg, I, K, La, Mg, Mn, Na, S, Sb, Sc, Se, Sm, Ti, V and Zn. As these elements in hair have wide concentration ranges, the differences in concentrations distribution between groups (sex, age, permanent treatment and regional difference) are discussed. A method for hair sampling is presented.  相似文献   

17.
Neutron activation analysis was applied to assess trace elements concentrations in head hair from healthy elderly people living in the São Paulo metropolitan area. Concentrations of As, Br, Ca, Cl, Co, Cr, Cu, Fe, K, La, Mn, Na, Sb, Se and, Zn were determined. Comparisons were made between the results obtained for dyed and non-dyed hair as well as for hair from females and males of two different age groups. The results were also compared with range values established by clinical laboratories and published data.  相似文献   

18.
Neutron activation analysis techniques were used to study sediments from Chautauqua Lake. The concentrations of Eu, Na, Mn, K, Br, As, Ga, La, Hf, Cs, Tb, Sc, Fe, Ta, Sb were determined and compared with similar data for the bedrock and soils surrounding the lake. The lake sediments are found to be enriched in Na, Mn, Br, As, Hf, Tb, Ta, and Sb relative to the surrounding source beds. High pairwise linear correlation coefficients (R~0.9) were found between the concentrations of antimony, cesium, and scandium. For many elements a relationship was indicated between their concentrations and the clay fraction of the sediment, possibly due to the higher cation exchange potential of the clay minerals.  相似文献   

19.
Evaluation of trace element contents in Swertia paniculata Wall.   总被引:1,自引:0,他引:1  
Important mineral elements (Fe, Zn, Mn, Cu, Co, Na, K, Ca and Li) were determined in the leaves and roots of Swertia paniculata collected from three different altitudes in three seasons using atomic absorption spectroscopy. The highest concentrations of Zn, Cu, Mn, Fe, Co, Na, K, Ca and Li were found to be 193.0?±?5.6, 26.0?±?7.6, 303.0?±?8.5, 1507.0?±?2.5, 88.0?±?1.2, 345.0?±?1.2, 11622.0?±?6.4, 3461.0?±?3.5 and 48.0?±?4.5?mg?kg(-1), respectively. The overall concentration of K was found to be the highest, whereas the level of Cu was the lowest. The concentrations of Cu and Li were quite low in all samples, whereas Zn, Mn, Co and Na were found in moderate concentration and K, Ca and Fe were found in very high concentrations in all the samples tested.  相似文献   

20.
Summary Laser ablation inductively coupled plasma-source mass spectrometry has been used to determine thirty elements (Na, Mg, Al, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, As, Rb, Sb, Cs, Ba, La, Ce, Nd, Sm, Eu, Dy, Ho, Yb, Hf, Ta, W, Th, U) in seven Chinese reference soils. The Surrey prototype spectrometer was employed with sample ablation by a free-running ruby laser. Concentrations in the soils (GSS-2 to GSS-8) were calculated from elemental responses and sensitivities derived from another soil in the series, namely GSS-1. Comparisons with previous neutron activation analyses are made. Rapid semiquantitative analyses are proved feasible. About eighty percent of the LA-ICP-MS determined concentrations were within a factor of two of the concentrations measured by INAA, and many were considerably closer than this. Precisions were typically in the range 2–10% RSD, but some were considerably poorer for elements present at trace levels.  相似文献   

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