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1.
To understand how nutrients are recycled in a particular soil - plant system, we have analyzed the kinetics of the elements Na, Mg, K, Ca, Mn, and Br throughout the life cycle of the plant. The plant sample was collected at 6 different stages of its growth. The effect of V (100 µM) on the element recycling system was also analyzed. The amount of the elements in each tissue of the plant, root, stem, petiole, leaf, and seed, were then determined by neutron activation analysis. The total elemental uptake rapidly increased when the plant developed from the juvenile to the adult phase. More than half of the Mg and Mn in cotyledon was transported to the younger leaves before the cotyledon was shed. From the pattern of movement of each element in plant tissue we have constructed an element recycling model in the soil-plant system. Based on the model, it was found that the amount of K to be a limiting factor for the recycling activity in the system.  相似文献   

2.
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   

3.
A nondestructive X-ray fluorescence technique has been developed to determine Na, Mg, Al, Si, P, S, Cl, K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, Br, Rb, Sr, Ba, and Pb in plants. The line element intensities were measured by an S4 Pioneer X-ray sequence spectrometer (Bruker AXS, Germany). The inversely proportional relationship was obtained between the analyte line intensity and mass of the plant, pressed on boric acid backing, for elements with an atomic number 11 < Z < 20. It was found that reduction of plant mass from 6 to 1 g leads to an increase in element determination sensitivity. The detection limits for 1 g of pressed plant were evaluated as μg/g: 5–20 (Na, Mg, Al); 1–4 (Si, P, S, Cl, K, Ca, Ti, Ba, Pb); 0.4-0.8 (Cr, Mn, Fe, Ni, Br, Cu, Zn, Rb and Sr). This technique was applied to determine the element composition of violets of Violaceae family, which are used in medicine.  相似文献   

4.
Instrumental neutron activation analysis has been successfully employed in three distrinct acid precipitation studies. These include the determination of ten (Al, Br, Ca, Cl, Cu, I, Mg, Mn, Na and V) elements in urban rainfall, elevated aluminum concentrations in acidified lakes and major ions (Ca, Cl, K, Mg and Na) in small-mouth bass kept in controlled pH environments. Quality control was assured by analyzing two certified standard reference materials prepared by the National Bureau of Standards (NBS 1643a) and National Research Council of Canada (hepatopancreas TORT-1 marine biological tissue).  相似文献   

5.
Hair samples were collected from 100 healthy people residing in Esfahan, Iran. The concentration of fourteen elements (Al, Br, Ca, Cl, Cu, Hg, I, K, Mg, Mn, Na, S, V, Zn) were determined by instrumental neutron activation analysis (INAA). The statistical results show that there are significant interrelations between some element such as: (Al-Mn, Al-V, Mg-Ca, Mn-V) and also there is no significant age correlation with any element. In addition, the results of this study are compared with the results obtained in England and New Zealand.  相似文献   

6.
We present Na, Mg, Al, K and Ca profiles, determined by neutron activationanalysis (NAA) in a soybean plant during its life cycle in water culture.The concentrations of Mg and Ca in leaves were higher than the other tissuesduring the developmental stage of a plant. The concentration of K was relativelyuniform within a plant. When a plant was treated with V, element uptake amount,especially Mg, K and Ca, was decreased throughout the life cycle. Vanadiumtreatment also induced low concentration of Mg and K in roots.  相似文献   

7.
Instrumental neutron activation analysis was used for the determination of Al, Br, Ca, Ce, Cl, Co, Cr, Cs, Eu, Fe, K, La, Mg, Mn, Na, Rb, Sb, Sc, Se, Ti, Th, V and Zn, ICP-AES for the determination Al, Ag, Ba, Be, Ca, Co, Cr, Cu, Fe, Ga, K, Li, Mg, Mn, Na, Ni, P, Sc, Sr, Ti, V and Zn and flameless AAS for the determination of Cd, Hg and Pb in egg plant, potatoes, green pepper (Leguminosae), vegetable marrow (Cucurbitaceae), pears, apple (Rosaceae), castor oil plant (Euphorbiaceae), lettuce (compositae), dill, parsley, coriander (Umbelliferae), and in some soil samples collected from Aswan province.  相似文献   

8.
This paper presents the results of the proficiency test exercise conducted in Pakistan for the determination of trace elements in mushroom reference material. Thirteen laboratories from different organizations of the country submitted trace elemental data on Al, As, Br, Ca, Cd, Ce, Cl, Co, Cr, Cs, Cu, Fe, Hg, K, Li, Mg, Mn, Na, P, Pb, Rb Sc, Si, Sm, Sr, Th, Zn. Results for Al, As, Br, Ca, Cd, Cl, Co, Cr, Cs, Cu, Fe, K, Mg, Mn, Na, Rb Sc, and Zn, in the mushroom material were reported by two or more participating laboratories and could be subjected to statistical evaluation. The original data of these trace elements was subjected to a computer program “Histo Version 2.1” provided by IAEA. The four outlier tests, i.e., Dixon, Grubbs, skewness and kurtosis were applied to the data sets. Consensus (overall) mean values, absolute standard deviation, relative standard deviation, standard error, median and range of values for these elements have been reported at a significance level of 0.05.  相似文献   

9.
In Nigeria, various parts of various species of native plants have long been used for dental hygiene, with reportedly considerable effectiveness. These materials are known as “chewing sticks”. This study was an effort to ascertain whether any unusual trace element concentrations might be present in Nigerian chewing sticks. Results are presented for 17 elements (Na, Mg, Al, Cl, K, Ca, Sc, V, Mn, Fe, Co, Zn, Br, Cs, La, Sm, Au) detected and measured in 12 species of such plants, via instrumental thermal-neutron activation analysis.  相似文献   

10.
Some essential elements in eleven plant medicines used at the Center for Scientific Research into Plant Medicine (CSRPM), Mampong-Akwapim, Ghana, for the management and cure of various diseases were determined by instrumental neutron activation analysis (INAA), using thermal neutrons at a flux of 5.1011 n.s-1.cm-2. The plant medicines were: Sirappac powder-E, Tina-A powder, Blighia powder, Aphrodisiac powder, Ninga powder and Lippia tea. The others are Olax powder, Ritchiea powder, Momordica powder, Kenken and Fefe powder. Concentrations of seventeen elements namely Al, Br, Ca, Cl, Co, Cu, Cr, K, Mn, Mg, Na, Rb, Sb, Sc, Ta, V, and Zn have been determined by short, medium and long irradiation times. Of these elements Co, Sb, and Sc are found to be present at the trace level, Br, Cu, Cr, Mn, Rb, Ta, V and Zn at the minor level, while Al, Ca, Cl, K, Mg and Na were generally at major level. The differences in the concentration of the elements are attributed mainly to soil composition and climate in which the plants grow. Standard reference material NIST SRM-1571 (Orchard Leaf) was analyzed simultaneously with the samples. The precision and accuracy of the method were evaluated using real samples and the standard reference material. It was found that the elemental concentrations measured in the NIST SRM-1571 were within ±10% of the reported values. The importance of these elements as related to human health and nutrition has been discussed.  相似文献   

11.
Tree rings and needles of young spruce clones from the immission area of the Al-refinery Ranshofen (Upper Austria), which had ceased production in 1992, were investigated by INAA. Short time irradiation was performed for determining, Al, Mn, Ca and Cl, while the elements Na, K, Rb, Ba, Zn, Fe, Sc, Cr, Co, Br and in some samples also Ca were determined via middle- and long-lived radioisotopes. Irradiation and counting conditions are given. Accuracy and sensitivity are sufficient to describe the trends of the element concentrations in needles and with the exception of Cr, Sc and Br, in tree rings. Ca-concentrations derived from49Ca (short-time irradiation) and47Ca (long-time irradiation) are compared and show good agreement Additionally Mg was determined in some samples by ICP-AES and if possble, by INAA. The results are compared.  相似文献   

12.
Summary Ten agricultural/food reference materials (RM): bovine muscle powder, corn starch, hard red spring wheat flour, soft winter wheat flour, whole milk powder, wheat gluten, corn bran, Durum wheat flour, whole egg powder and microcystalline cellulose, were prepared by milling, irradiation, sieving, blending and packaging procedures. Homogeneity tests for 14 elements in randomly selected units were performed by the initiating laboratories by application of various analytical methods. Al, Ca, Cu, Fe, K, Mg, Mn, Na, Sr and Zn were determined by acid digestion flame atomic absorption spectrometry, and Cd, Co, Ni and Pb using acid digestion graphite furnace atomic absorption spectrometry after separation/preconcentration of the analytes by co-precipitation. In addition, the extensive set of analytical results obtained from the interlaboratory cooperative characterization campaign was assessed to provide homogeneity estimates for other elements. Measures of homogeneity were estimated from the within-laboratory precision from the more precise laboratories. All materials exhibited acceptable homogeneity for virtually all 29 elements (Al, As, B, Ba, Br, Ca, Cd, Cl, Co, Cr, Cu, Fe, Hg, I, K, Mg, Mn, Mo, N, Na, Ni, P, Pb, Rb, S, Se, Sr, V, Zn) for which best estimate concentration values were available, an essential pre-requisite in establishing reference values for these materials. Sixty-two percent of all homogeneity coefficients of variation (CV) were below 5%, with Br, Ca, Cl, Mg, Na, P, Zn and especially K and N exhibiting very high homogeneity CV less than 1% in some cases.Contribution no. 92–148 from Centre for Land and Biological Resources Research  相似文献   

13.
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   

14.
The mineral status of whole plant samples of Phyllanthus and its growth substratum was determined using Instrumental Neutron Activation Analysis. A total of 11 elements were detected in both whole plant and soil samples with varying concentrations depending on area of collection as well plant or it soil substratum. Comparatively, the concentration of all the elements except Cl, Ca and Br was higher in the soil samples than the whole plant indicating that the plant obtained these elements from the growth substratum. For the plant samples, the concentration of tungsten (W) and arsenic (As) were below the detection limits while for the soil sample chlorine (Cl) and calcium (Ca) were below detection limits. Three of the elements namely Mg, Ca and K detected in the plant samples are macroelements and were therefore detected in higher concentrations in the plant samples. The element with the highest concentration was K and it ranged from 1,215.44 to 5,658.06 and 0.64 to 1.20 % in soil and whole plant samples respectively. Arsenic (As) is considered as a toxic element and its concentration below detection limits in the whole plant sample makes it pharmacologically safe for human consumption.  相似文献   

15.
The concentration of 28 elements in tobacco and cigarette paper in an Egyptian Cigarette were determined using instrumental neutron activation analysis. These elements are: Al, As, Ba, Br, Ca, Ce, Cl, Co, Cr, Cs, Eu, Fe, Hf, K, La, Mg, Mn, Na, Ni, Rb, Sb, Sc, Se, Sr, Th, Ti, V and Zn. The cigarette filter (before and after normal smoking) and the produced ash were analyzed to determine the adsorption of the elements on the filter and their remains in ash. The material balance for the determined elements were calculated.  相似文献   

16.
The concentrations of elements in rice, locally cultivated in two regions of Tanzania (Mbeya and Morogoro), were determined using Instrumental Neutron Activation Analysis (INAA) for Na, Mg, Al, Cl, K, Ca, V, Mn, Cu and Br, and Particle-Induced X-Ray Emission (PIXE) for P, Fe and Zn. There were no statistical differences in concentrations of the essential elements Fe, Zn, Cu and P in rice from both regions. There was also no significant correlation between grain P and Fe content, suggesting the possibility of growing Tanzanian rice with low phytic acid and high Fe contents.  相似文献   

17.
Instrumental neutron activation analysis, INAA, was utilized for the determination of Al, Au, Br, Ca, Cl, Co, Cr, Cu, Fe, I, K, Mg, Mn, Na, Rb, Sc, V and W in 12 Tilapia Nilotica samples collected from the Aswan High Dam Lake following the destructive techniques.  相似文献   

18.
Summary Rib bones of Brazilian people were analyzed by neutron activation analysis to evaluate element composition. Freeze-dried cortical and trabecular tissues, separately, and calcinated total rib tissues were analyzed. The concentrations of the Ba, Br, Ca, Cl, Fe, K, Mg, Mn, Na, P, Rb, Sr, and Zn elements were determined. Comparisons between the results obtained in cortical and trabecular bones indicated significant differences in the concentration for several elements. Results obtained in cortical and trabecular bones were also compared with literature values.  相似文献   

19.
As part of the SAFARI-92 biomass buming experiment, aerosol collections were carried out with several size-fractionating sampling devices at a number of sites in Southern Africa. One of the samplers used at all ground-based sites was a stacked filter unit (SFU). The SFU samples were analyzed by both INAA and PIXE analysis. The present paper gives an intercomparison of the analytical results obtained in order to assess the accuracy and to check the quality assurance of the analytical procedures. Twenty-one common elements were determined by both INAA and PIXE. Concentrations of 13 elements (i.e., Na, Mg, Al, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Zn and Br) were generally measured with sufficient precision in both techniques for performing the intercomparison. The INAA and PIXE data were compared in terms of PIXE/INAA concentration ratios on a sample by sample basis for the coarse and fine size fraction separately. the atmospheric concentrations for K, Mn and Fe agreed within 5–10%, the agreement between the data for the other common elements was typically better than 15%. Possible explanations for lower than 1.0 ratios for Cl, Br and Na are presented. The common elements were classified into groups according to their detectability and sensitivity in each technique.  相似文献   

20.
The nutrient value of Thai rice and bean in terms of minor and trace element content has been evaluated using INAA. Six varieties of rice and six of beans bought from three local markets in 2006–2007 were investigated under this study. Elemental compositions were determined using the comparator technique. Precision, accuracy and detection limits of each element found were also calculated. Three minor (Ca, K, Mg) and eight trace elements (Al, As, Br, Cl, Cu, Fe, Mn, Zn) were determined in these Thai foods.  相似文献   

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