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1.
Twenty-four Spanish thyme honey samples were analyzed using inductively coupled plasma optical emission spectrometry (ICP-OES). Twenty-four minerals were quantified for each honey. The elements Al, As, Ba, Ca, Cr, Cu, Fe, K, Li, Mg, Mn, Na, P, Pb, S, Se, Si, Sr, and Zn were detected in all samples; seven elements are very abundant (Ca, K, Mg, Na, P, S, and Si), and six are not abundant (Al, Cu, Fe, Li, Mn, and Zn). Eleven of them are trace elements (As, Ba, Cd, Co, Cr, Ni, Mo, Pb, Se, Sr, and V) at <1 mg kg(-)(1). Classification of thyme honeys according to their origin (coast, mountains) was achieved by pattern recognition techniques on the mineral data. By means of principal component analysis, a good separation by geographical origin is obtained when scores for the two first principal components are plotted. Classification functions of 11 metals (Al, As, Cr, Cu, K, Li, Mg, Na, P, S, and V) were obtained using stepwise discriminant analysis and applied to classify correctly approximately 100% of the honey samples.  相似文献   

2.
Duplicate, bulked surface soil samples, from sites 10m apart, were collected at 97 locations 1000 m apart on a regular grid measuring 8x11 km. Data were obtained for Ag, Ba, Be, Cd, Co, Cr, Cu, Li, Mn, Ni, Pb, V and Zn. One field sample was a good predictor of its nearby duplicate for Co, Cu, Ni and Pb, satisfactory for Ba, Be, Cr, Mn and Zn, but poorer for Cr, Li and V. Maps of the variation in precision of the field samples did not reveal any association between abandoned mine sites and high variability. The median coefficient of variation for trace elements in the field duplicates was between 8 and 19.5%. The duplicated field data were averaged to yield a mean soil metal concentration at each sample location. Concentrations of Ba, Be, Cr, Li, Sr and V were comparable with other published values for similar soils in Missouri. Concentrations of Co, Cu, Mn, Ni, Pb and Zn were higher which was explained by pollution from mining activities. A graphical technique was used to calculate background levels for metals in the second group. Samples of forest litter were collected at 12 locations: Ag, Ba, Cd, Mn, Sr and Zn concentrations were higher in the litter whereas Li and V concentrations were higher in the subjacent mineral soil. Computer isoline maps of the distribution of elements revealed an association between areas of high soil Cu, Co, Ni, Pb and Zn and abandoned mines or mineralized rocks.  相似文献   

3.
Wines from three important wine-producing regions, Stellenbosch, Robertson, and Swartland, in the Western Cape Province of South Africa, were analyzed by ICP-MS and the elemental composition used in multivariate statistical analysis to classify the wines according to geographical origin. The method is based on the assumption that the provenance soil is an important contributor to the trace element composition of a wine. A total of 40 elements were determined in 40 wines. Of these, 20 elements: Li, B, Mg, Al, Si, Cl, Sc, Mn, Ni, Ga, Se, Rb, Sr, Nb, Cs, Ba, La, W, Tl, and U showed differences in their means across the three areas. In a stepwise discriminant analysis procedure, functions based on linear combinations of the log-transformed element concentrations of Al, Mn, Rb, Ba, W, and Tl were generated to correctly classify wines from each region. In an alternative approach, a pairwise discriminant analysis procedure, not previously used in wine provenance studies, was tested. In this procedure, the classification was done in three steps, with each step classifying a wine as coming from a certain region or not. The combination of elements characterizing wines from a particular region was different in each region. The discriminant functions were based on the following elements: Al, Mn, Rb, Ba, and W for Stellenbosch; Se, Rb, Cs, and Tl for Robertson; and Al, Mn, Rb, Sr, Ba, and Tl for Swartland. After this procedure, the classification of the wines into one of the groups was 100% successful.  相似文献   

4.
Different sample preparation methods were evaluated for the simultaneous multielement analysis of wine samples by inductively coupled plasma optical emission spectrometry (ICP-OES) and inductively coupled plasma mass spectrometry (ICP-MS). Microwave-assisted digestion in closed vessel, thermal digestion in open reactor, and direct sample dilution were considered for the determination of Li, Be, Na, Mg, Al, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Sr, Y, Mo, Cd, Ba, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Tl, Pb, and Bi in 12 samples of red wine from Valencia and Utiel-Requena protected designation of origin. ICP-MS allows the determination of 17 elements in most of the samples, and using ICP-OES, a maximum of 15 elements were determined. On comparing the sample pretreatment methodology, it can be concluded that the three assayed procedures provide comparable results for the concentration of Li, Na, Mg, Al, K, Ca, Mn, Fe, Zn, and Sr by ICP-OES. Furthermore, ICP-MS data found for Cu, Pb, and Ba were comparable. Digestion treatment provides comparable values using both total decomposition in open system and microwave-assisted treatment for Cu by ICP-OES and for Cr, Ni, and Zn by ICP-MS. Open vessel total digestion provides excess values for Cr, Mn, Fe, and Zn by ICP-OES and defect values for Se. However, direct measurement of diluted wine samples provided uncomparable results with the digestion treatment for Mn, Cu, Pb, Zn, Ba, and Bi by ICP-OES and for Mg, Cr, Fe, Ni, and Zn by ICP-MS. Therefore, it can be concluded that microwave-assisted digestion is the pretreatment procedure of choice for elemental analysis of wine by ICP-based techniques.  相似文献   

5.
厩肥对粉煤灰微量元素释放规律影响的研究   总被引:2,自引:0,他引:2  
该文对粉煤灰在降雨淋洗条件下微量元素的释放规律进行了室内模拟试验。试验处理分别为粉煤灰、粉煤灰+石灰、粉煤灰+石灰+厩肥及其混合物的堆肥腐熟4种情况。实验结果显示淋出液中B、Sr、Ba和Li的最大浓度大于1 mg/L,而其它元素均小于此值。石灰的应用增大了淋出液中B和Ba的浓度而降低了Li、Mo和Cr的浓度;厩肥的应用及其堆肥腐熟处理增大了B、Mo、Zn、V以及Cu、Ni、Cd、As、Mn、Ti、Co、Sn和Se的浓度,而降低了Sr、Ba、Li和Cr的浓度。除V外,淋出液中所有微量元素的浓度随淋出液体积的增加而减小。Cr、Zn以及Cd、Cu和As可能是粉煤灰对环境产生潜在危害的主要元素。  相似文献   

6.
Element-concentration baselines are given for Parmelia sulcata and associated soils. Parmelia chlorochroa was found sporadically and therefore only representative concentration ranges are reported for this species. Element data include (1) for lichens; Al, As, Ba, B, Ca, Cr, Cu, Fe, Hg, Mn, Ni, P, Sr, S, Ti, V, Y, and Zn; and (2) for soils: Al, Ba, Be, Ca, Cs, Cr, Cu, Fe, Hg, Mg, Mn, Ni, Nb, P, Pb, Sr, S, Ti, V, Y, and Zn. Very little (usually < 10 %) of the variability in the element data for lichen material occurs regionally (> 7.2 km); thus, P sukata is, in general, chemically similar throughout the park. This same uniformity was found for soil geochemistry. Numerous samples collected at close intervals would be required, therefore, to produce detailed element-concentration maps for P. sulcata and soils. No instances of elemental phytotoxic conditions were found; however, P. sulcata apparently possesses large concentrations of Ba, Cu, Fe, Pb, S, V, and possibly Zn.  相似文献   

7.
Grain amaranth has been suggested as an alternative to marine animals as a natural source of squalene. Oil contents, squalene contents, and fatty acid profiles were determined in 11 genotypes of four grain amaranth species. Although the oil contents of grain amaranth were low (from 5.1% in Amaranthus tricolor to 7.7% in Amaranthus cruentus) as compared to other oil-containing grains, high concentrations of squalene were found in total lipids, ranging from 3.6% in Amaranthus hypochondriacus to 6.1% in A. tricolor. The major fatty acids in Amaranthus oil consisted of palmitic acid (19.1-23.4%), oleic acid (18.7-38.9%), and linoleic acid (36.7-55.9%). A high degree of unsaturation was observed in Amaranthus oils, with S/U ratios of 0.26-0.32. A method to isolate and purify the squalene from Amaranthus oil was developed. After the saponification of K112, the squalene content increased from 4.2% in the crude oil to 43.3% in the unsaponifiables by the removal of the saponifiables. The unsaponifiables were fractionated by silica gel column chromatography to get highly purified squalene. The squalene purity in certain fractions was as high as 98%. Combining the fractions rich in squalene gave a 94% squalene concentrate, with a yield of 90%. The structure of squalene in the purified sample was confirmed by comparison of its ultraviolet spectrum with a standard and from its nuclear magnetic resonance spectra.  相似文献   

8.
Data are presented for 32 elements (Li, Be, B, Ti, V, Cr, Mn, Co, Ni, Cu, Zn, Ge, As, Rb, Sr, Y, Zr, Mo, Ag, Cd, Sb, Cs, Ba, La, Ce, Pr, Nd, Sm, Hf, Tl, Pb, Bi) in organic-rich surface soils in Norway, based on samples from 464 sites. By considering geographical distributions based on isopleths, results from factor analysis, and ANOVA of median values from 12 different geographical regions, the contributions from natural and anthropogenic sources are estimated for each element. Long-range atmospheric transport of pollutants from areas out of Norway is a dominant source for Cd, Sb, Pb, and Bi and also a strongly contributing factor for Zn, As, Mo, and Tl. Also V, Ni, Cu, and Ge are somewhat affected, but other factors dominate for these elements. Local point sources of pollution provide significant contributions to soil concentrations of Ni, Cu, Zn, As, Mo, and Cd. The local bedrock is the overriding source of Li, Be, Ti, V, Cr, Mn, Rb, Zr, Cs, Ba, REE, Hf, and probably of Ge and Ag. Surface enrichment by root uptake in plants and return to the soil surface by decaying plant material is particularly evident for Mn, Zn, Rb, Cs, and Ba. These elements show no clear difference between south and north in the country, indicating that their plant uptake does not depend on latitude. In the case of B and Sr, atmospheric deposition of marine aerosols is an important source. Rb and Ag, and to a less extent Mn, Ga, and Ba, appear to be depleted in soils near the coast presumably due to cation exchange with airborne marine cations.  相似文献   

9.
通过对老官台全新世黄土剖面12种微量元素的测定分析,结合本剖面已测定的粒度、磁化率、光释光(OSL)年龄,研究和揭示了它们在表生环境下的地球化学特征和古气候意义。微量元素在风化成壤过程中,其活动性由强至弱顺序为BaSrCdPbLiZnCuCrMnCoRbNi。其中Rb、Li、Cr、Co、Zn、Cu、Mn、Ni八种元素在土壤形成过程中相对富集,含量较高;Sr、Ba、Cd三种元素在土壤中相对淋失,含量较低;但Zn、Cu、Mn、Ni、Pb五种元素对黄土层和土壤层的区别不是很明显。因此,Rb、Li、Cr、Co的高含量反映了较温湿的成壤环境,低含量反映了较冷干的粉尘加积环境;而Sr、Ba、Cd低含量反映了较温湿的成壤环境,高含量反映了较冷干的粉尘加积环境。Pb、Zn、Cu、Mn、Ni、Cd元素含量在表土层中的富集主要与现代耕作活动或工业污染有关,反映了人类活动强度的不断增强。LGT剖面主要微量元素的变化清楚地记录了关中盆地自末次冰消期以来气候环境经历的显著波动变化。  相似文献   

10.
Eurasian Soil Science - Background concentrations of heavy metals (Cu, Zn, Ni, Co, Fe, Mn, Cr, Pb, Hg, Cd, Ba, Sr, and Sc) in soils and bottom sediments were determined for the background and...  相似文献   

11.
Depth concentration profiles of 26 elements, i.e. trace elements (As, Ba, Cd, Co, Cr, Cu, Hg, Ni, Pb, Rb, Sr, V and Zn), lithophiles (Si, Al, Fe, Mn, Na, K, Mg, Ca and Ti) and nutrients (C, P, N, S) have been established in a sediment core collected at the Respomuso Lake (Pyrenees, Spain). This high altitude lake of glacier origin was transformed into reservoir in the fifties of last century. Correlations among the depth profiles of the above elements were established. HCl-extractable elements, which are better related to bioavailability, followed the profiles of total contents. Principal component analysis was applied to establish the binding behaviour of trace elements in the sediment matrix and, in turn, to search for their anthropogenic or natural sources. It was seen that Cu, Ni, Pb, Sr and Zn clustered together, and with exception of Sr, they were not clearly associated with any major component of the sediment. Their depth profiles correlate well with each other, hence indicating their presence as a result of atmospheric pollution. Redox-sensitive elements such as Fe and Mn follow a similar trend along the vertical profile. Depth profiles of As an Co correlate well with those of Fe and Mn. Principal component analysis showed that As, Co, Fe and Mn clustered together, which confirms the close association of As and Co with Fe-Mn oxyhydroxides. As concentrations in many strata exceed the ERM value, and therefore, significant biological effects are expected. Dissolution of minerals such as pyrite, chalcopyrite and galena taking part in the mineralogy of this area accounts for the As concentration found. Ba, Cr, Rb and V were associated with the sediment matrix (aluminosilicates), hence showing low mobility.  相似文献   

12.
我国几种土壤中铁锰结核的元素组成和地球化学特点   总被引:7,自引:0,他引:7  
The objective of this research was to isolate a dichlorvos (2,2-dichlorovinyl dimethyl phosphate)-degrading strain of Ochrobactrum sp., and determine its effectiveness in remediation of a dichlorvos-contaminated soil. A dichlorvos-degrading bacterium (strain DDV-1) was successfully isolated and identified as an Ochrobactrum sp. based on its 16S rDNA sequence analysis. Strain DDV-1 was able to utilize dichlorvos as a sole carbon source, and the optimal pH and temperature for its cell growth and degradation were 7.0 and 30 ℃, respectively. Also, the growth and degradation of strain DDV-1 showed the same response to dissolved oxygen. In addition, the soil degradation test indicated that in soil spiked with 100 mg L^-1 or 500 mg L^-1 dichlorvos and inoculated with 0.5% or 1.0% (v/v) strain DDV-1, complete degradation of dichlorvos could be achieved in 24 h. The present study showed that strain DDV-1 was a fast dichlorvos-degrading bacterium in soil. However, further research will be needed to clarify the degradation pathway and the properties of the key enzymes involved in its biodegradation.  相似文献   

13.
The objective of this study was to demonstrate the feasibility of chemical profiling methods combined with multivariate methods to differentiate the geographical growing regions of pistachios (Pistachia vera). Elemental analysis (Ba, Be, Ca, Cu, Cr, K, Mg, Mn, Na, V, Fe, Co, Ni, Cu, Zn, Sr, Ti, Cd, and P) of pistachios samples was performed using inductively coupled plasma atomic emission spectrometry. Analysis of inorganic anions and organic acids (selenite, bromate, fumarate, malate, selenate, pyruvate, acetate, phosphate, and ascorbate) of pistachio samples was performed using capillary electrophoresis. Bulk carbon and nitrogen isotope ratios were performed using stable isotope MS. There were nearly 400 pistachio samples analyzed from the three major pistachio growing regions: Turkey, Iran, and California (United States). A computational evaluation of the trace element data sets was carried out using statistical pattern recognition methods including principal component analysis, canonical discriminant analysis, discriminant analysis, and neural network modeling. Several linear discriminant function models classified the data sets with 95% or higher accuracy. We report the development of a method combining elemental analysis and classification techniques that may be widely applied to the determination of the geographical origin of foods.  相似文献   

14.
pp. 875–880

The trace-element composition of kernel in pickled Japanese apricot (Prunus mume Sieb. et Zucc.) was determined using an inductively coupled plasma optical emission spectrometer in order to distinguish between Japanese products and Chinese products.

Strontium and barium concentrations in the kernels of Chinese products were 10 or more times those of the Japanese ones. When based on 8.0 mg kg?1 of strontium concentration in kernel, 93.2% of sample was distinguished as Japanese products or Chinese ones.

Applying principal component analysis using 9 elements (Mn, Zn, Fe, Ni, Ba, Sr, Cu, Co, Cr), the pickled Japanese apricots tend to separate into two countries. Linear discriminant analysis (LDA) using 9 elements allowed a reasonable classification of pickled Japanese apricots according to the country of production.

The result of the analysis of K-nearest neighbors (KNN) was better than that of LDA.  相似文献   

15.
C.W. Childs 《Geoderma》1975,13(2):141-152
A selection of iron-manganese concretions from five reference soil profiles and a buried loess deposit in New Zealand have been studied. Concretions appear to have developed by the precipitation of amorphous iron and manganese oxides among soil particles. X-ray fluorescence analysis shows that the concentrations of Fe, Mn, Co and Ba in the concretions are generally higher, and those of K, Ca, Si, and Al are generally lower, than in the soil materials surrounding the concretions, whereas Ti, Zn, S, and P show little variation. Other approximate analyses indicate that Cu, Ni, Mo, V, and Pb tend to be concentrated in concretions but for Ga, Zr, Sr, Li, and Rb there was no discernible trend. Electron probe microanalyses of some concretions show that Co and Ba are concentrated in Mn-rich phases rather than Fe-rich phases.Comparison with published results for concretions (Mn nodules) from the ocean floor and the floor of Lake Ontario indicates that, on average, marine concretions have higher Mn, and lower Si and Al concentrations than soil concretions, and that marine concretions have lower Fe concentrations than either Ontario or soil concretions.  相似文献   

16.
方肇伦  宋达泉  叶炳 《土壤学报》1963,11(2):130-142
土壤中的微量元素在动植物生活中所起的重要作用日益被人们所重视.了解土壤中的这一部分资源对指导微量元素肥料的施用,从而达到农业增产以及对消除由土壤微量元素缺乏或过剩引起的某些动植物病害均具有重要的意义.探讨土壤微量元素在土壤剖面中的累积和迁移及其地理分布规律,则可进一步阐明土壤发生过程与生物地球化学特性的关系.  相似文献   

17.
Eleven metals (K, Na, Ca, Mg, Fe, Cu, Zn, Mn, Sr, Li, and Rb) were determined in 83 red wines from the Canary Islands. The wines presented high concentrations of Na, and the concentrations of Cu and Zn were much lower than the maximum concentrations established by the International Office of Vine and Wine (OIV). Applying principal component analysis, the dimension space was reduced to five principal components that explain 76.4% of the total variance, and the wines tend to separate on the basis of the island of production. Linear discriminant analysis (LDA) allowed a reasonable classification of wines according to the island of production. When artificial neural networks (Kohonen self-organizing maps and back-propagation feed-forward as unsupervised and supervised techniques, respectively) were applied on the matrix of data constituted by the analyzed metals, the results improved in relation to those obtained by other multivariate methods observing a differentiation of wines according to island of production.  相似文献   

18.
To characterize potatoes according to their geographic origin and variety, 10 mineral and trace elements (Mg, Cr, Mn, Fe, Ni, Cu, Zn, Sr, Cd, and Ba) were determined in Italian potato samples. The data collected were successively elaborated using statistical techniques, namely, linear discriminant analysis (LDA). LDA was able to classify and discriminate the potatoes from Fucino both from those of other areas of Italy and from those of the four provinces of Abruzzo. A net separation between the Fucino potatoes and those of the other areas of Abruzzo was observed. LDA discriminated also the three potato varieties cultivated in the Fucino basin. The presence of these 10 mineral and trace elements was a good means for establishing the geographical place of origin of Fucino potatoes.  相似文献   

19.
Baseline element concentrations are given for Spanish moss (Tillandsia usneoides), loblolly pine (Pinus taeda), and associated soils. Baseline and variability data for ash, Al, Ba, C, Ca, Cd, Ce, Co, Cr, Cu, Fe, K, La, Li, Mg, Mn, Na, Nb, Nd, Ni, P, Pb, S, Sc, Sr, Th, Ti, V, Y, and Zn are reported; however, not all variables are reported for all media because, in some media, certain elements were below the analytical detection limit. Spatial variation in element concentration among and within 0.5 km grid cells are given for each of the media. In general, only a few elements in Spanish moss showed statistically significant landscape patterns, whereas several elements in loblolly pine and in soils exhibited differences among sampling grids. Significant differences in the concentration of three elements in Spanish moss and eight elements (including total S) in loblolly pine were observed between two sampling dates (November and June); however, the absolute amount of these differences was small. Except for perhaps Ni and Pb concentrations in Spanish moss, element levels in all sample media exhibited ranges that indicate natural rather than anthropogenic additions of trace elements.  相似文献   

20.
戴昭华  黄衍初 《土壤学报》1986,23(4):382-387
本文用因子分析方法对海南岛土壤中若干元素的分布规律进行初步探讨.通过Q型分析表明,该地区土壤样品主要分成两大类.一类为富含铁族元素,另一类为铁族元素含量相对较低的.由R型分析结果表明,除铁族元素为一类外,易淋溶元素锶、抗风化元素锆分别各成一种类型.说明土壤中元素分布与成土母质类型和元素地球化学性质有关.  相似文献   

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