Determination Of Element Concentrations Research Articles

Use and calibration of portable X-Ray fluorescence analysers: application to lithogeochemical exploration for komatiite-hosted nickel sulphide deposits

Portable X-Ray Fluorescence (pXRF) analysers allow on-site geochemical analysis of rock powders and drill core. The main advantages of pXRF analysis over conventional laboratory analysis are the speed of data collection and the low cost of the analyses, permitting the collection of extensive, spatially representative datasets. However, these factors only become useful if the quality of the data meets the requirements needed for the purposes of the study. Here, we evaluate the possible use of portable XRF to determine element concentrations and ratios used in exploration for komatiite-hosted nickel sulphides. A portable XRF analyser was used to measure a series of chalcophile and lithophile element concentrations (Si, S, K, Ca, Ti, Cr, Fe, Ni, Cu, Zn, As, Sr, and Zr) of 75 samples from three komatiite units associated with nickel sulphide ores in the Yilgarn Craton, Western Australia. Crucial steps in the study were the development of a strict calibration process as well as numerous data quality checks. The 670 analyses collected in this study were compared with conventional laboratory XRF data on discriminant diagrams commonly utilized in exploration for komatiite-hosted nickel sulphides (Cr vs Ni and Ni/Ti vs Ni/Cr). After comparing the results obtained with pXRF during this study with the laboratory values, we can conclude that portable XRF analyses can be used for rapid assessment of the nickel sulphide prospectivity of komatiites provided that strict control protocols are followed. Supplementary Material: is available at http://www.geolsoc.org.uk/SUP18706

Heavy Metal Pollution of In-situ and Surrounding Soils Profiles at Municipal Solid Waste Dumpsite

Aims: To investigate the levels, variability and degree of heavy metal pollution in in-situ municipal solid waste dumpsite soil (WDS) compared to adjoining area (CS) at 100 – 120m from dumpsite as a contribution to global knowledge of pattern of pollution and data base at dumpsite. Study Design: Field-scale investigation of nine heavy metals (HM) at source pollution site and surrounding soil. Place and Duration of Study: Uyo municipal solid waste dumpsite in 2010. Methodology: Core sampling of soil at solid waste dumpsite and at 100 – 120m away, taken at 0-10cm and 10-20cm profile depths at 4 spatially different points. Acid digestion of HM in soil samples and determination of elemental HM concentration by flame AAS. HM pollution level was assessed using contamination factor, metal pollution index; ANOVA, and covariance for spatial variability. Results: Mean concentrations of nine heavy metals at municipal waste dumpsite soil were significantly (P < .01) higher than the un-dumped surrounding soil, and gave high mean metal pollution index of 5.21 for the overall soil profile. Toxicity was indicated for Fe, Ni, Pb, and B. Correlation between mean HMs at WDS and CS was very low (R = .488) but difference was significant (P = .05), indicating no lateral transfer to fringe area at Original Research Article British Journal of Applied Science & Technology, 4(8): 1198-1214, 2014 1199 100 – 120m away. Conclusion: Heavy metal pollution in municipal solid waste dumpsite soil was higher at all profile depths than in control soil with contamination factors of 3-22 times the control soil values. Pollution was site-specific / anthropogenic (from waste deposition and leachate) rather than terrigenous. Fringe fields at 100-120m from dumpsite, except downslope, were buffered from dumpsite pollution. More research on deeper profile and minimum pollution free buffer distance are recommended.

Quantification of trace element contents in frozen fluid inclusions by UV-fs-LA-ICP-MS analysis

We have developed a new analytical setup for the determination of trace element concentrations in fluid inclusions by UV-fs-LA-ICP-MS. Laser ablation was performed at a low temperature of −40 °C by using a modified heating–freezing stage as the ablation cell. With this method it was possible to successfully analyse 53 of 55 frozen synthetic NaCl–H2O fluid inclusions in quartz, covering a size range between 8 μm and 25 μm down to a depth of 50 μm. The high success rate could be achieved as the 194 nm UV-fs-laser allows excellent control over the opening procedure of frozen fluid inclusions. Trace element analyses were performed with a fast scanning magnetic sector field ICP-MS. The lower limits of detection for fluid inclusion analysis vary from 0.1 μg g−1 (for 209Bi) to 10 μg g−1 (for 39K). The typical analytical uncertainty, depending on the element and respective concentration level, ranges between 10% and 30% (1RSD), based on the reproducibility of experimentally synthesized fluid inclusions. All elements from a stock solution, which behaved inert during the HP/HT experiments (B, K, Cd, Te, Tl, Pb and Bi), could be recovered in the synthetic inclusions at concentrations that correspond within their specific analytical uncertainties to their original concentration of 53 μg g−1. The method represents a highly efficient tool for the determination of accurate trace element data on low concentration levels in small fluid inclusions with a high success rate of >90%. The latter is particularly advantageous considering the commonly time consuming characterization of fluid inclusions.

An assessment of urban habitat contamination with selected heavy metals within the city of Katowice using the common dandelion (Taraxacum officinale Web.) as a bioindicator

Abstract The common dandelion (Taraxacum officinale Web.) is considered to be a good indicator species due to its wide spread and high tolerance to harsh environmental conditions. It was used in this study to assess contamination with selected heavy metals (Zn, Pb, Cd) within urban habitats of the city of Katowice (southern Poland). Samples were collected from outside the forest regions. Content of heavy metals was determined using Flame Atomic Absorption Spectroscopy (F-AAS). The soil mineralization was conducted using 50,0 cm3 10% HNO3. Determination of elemental concentrations in the plant material was carried out with the “wet” method using heating blocks for a period of 7-10 days. The following concentration ranges for individual elements in soil were found: 14,03–2049,50 mg kg−1 (Pb), 17,91–4118,00 mg kg−1 (Zn), 0,25–52,93 mg kg−1 (Cd). Concentrations within the leaves of common dandelion were: 5,52–93,04 μg g−1 (Pb), 71,71–807,15 μg g−1 (Zn), 0,10–15,69 μg g−1 (Cd). Plants from the most heavily contaminated soils were characterised by the lowest bioaccumulation coefficient. The most contaminated areas were the districts: Szopienice-Burowiec and Wełnowiec-Józefowiec, while the least contaminated were the southern districts of Katowice (i.e. Zarzecze, Podlesie). There is also a clear link between the content of heavy metals in soils examined in this study and the land use.

Status and changes of soil nutrients in rhizosphere of Abelmoschus manihot different planting age

Using soil chemical analysis method and combining with ICP-AES determination of mineral nutrition element content in rhizosphere soil of different planting age Abelmoschus Corolla Results show that along with the increase of planting age, the nitrogen (total N), available P and organic matter in rhizosphere soil of Abelmoschus Corolla content declined year by year and the soil got acidification. Heavy metal element content in agricultural land does not exceed national standards, but the content of element mercury (Hg) in rhizosphere soil of different planting age Abelmoschus Corolla declined. Request of microelement such as manganese (Mn) and zinc (Zn) had a increase tendency, but the content of magnesium (Mg) and sodium (Na) increased, and other nutrient elements had no changed rules or unchanged apparently. Consequently, exploring the change rules of different planting age Abelmoschus Corolla soil in rhizosphere as theoretical guidance of rational fertilization and subducting continuous cropping obstscles.

Ellipsometric characterization of multi-component thin films: Determination of elemental content from optical dispersion

This paper provides the correlation between the compositions of a given thin film to its optical dispersion properties. Gladstone–Dale (G–D) relationships have been used in optical mineralogy to relate density of crystalline compounds to their average refractive index. We purport to use a ‘reverse’ G–D approach and determine the composition of multi-component thin films from their optical properties. As a model system, we focus on complex perovskite ferroelectric thin film and apply the derived relationships to determine the stoichiometry. The wavelength dispersion of refractive index and extinction coefficient of various Pb(Zr,Ti)O3 (PZT) thin films was measured using Variable Angle Spectroscopic Ellipsometry. Elemental compositions were measured using Energy Dispersive X-ray analysis and Electron Probe Micro Analysis. Wemple–DiDomenico, Jackson–Amer, Tauc and Urbach optical relationships and related parameters were used to extract correlations to elemental content. Both theoretical and semi-empirical approaches to calculate the electronic polarizability of PZT were employed and their variation with elemental content was computed. Perovskite tolerance and octahedral factors were also analyzed against the optical and polarizability parameters. Lastly, these factors and relationships were combined to realize a model for predicting the elemental content of a thin film system.

Toxic Element Profiles in Selected Medicinal Plants Growing on Serpentines in Bulgaria

Populations of medicinal plants growing on serpentines and their respective soils were analyzed for Fe, Ni, Mn, Cr, Co, Cd, Cu, Zn, and Pb using inductively coupled plasma atomic emission spectrometry. Aqua regia extraction and 0.43 M acetic acid extraction were used for the quantification of pseudototal and bioavailable fractions, respectively, of elements in soil and nitric acid digestion for determination of total element content in plants. Screening was performed to (1) document levels of toxic metals in herbs extensively used in preparation of products and standardized extracts, (2) compare accumulation abilities of ferns and seed plants, and (3) estimate correlations between metal content in plants and their soils. The toxic element content of plants varied from site to site on a large scale. The concentrations of Fe and Ni were elevated while those of Cu, Zn, and Pb were close to average values usually found in plants. The highest concentrations for almost all elements were measured in both Teucrium species. Specific differences in metal accumulation between ferns and seed plants were not recorded. The investigated species are not hyperaccumulators but can accumulate toxic elements, in some cases exceeding permissible levels proposed by the World Health Organization and European Pharmacopoeia. The harvesting of medicinal plants from serpentines could be hazardous to humans.

Comparison of Methods for the Sulfur Compounds and Elemental Sulfur Analysis in High-Sulfur Natural Gas

Some gas fields with high hydrogen sulfide content, such as Luojiazhai, Dukouhe and Puguang Gas Fields, are found in Northeast Sichuan. For exploring and utilizing high sulfur natural gas reservoirs, it is essential to quantificational analysis of sulfur compounds and elemental sulfur in high sulfur natural gas. Determination of hydrogen sulfide content in natural gas with a laser method has many advantages, including on-site measurement, fast response, wide application scope, high accuracy, high reliability, and low maintenance. When the hydrogen sulfide concentration is 1% to 20%, the relative deviation of the analysis value to the standard value is less than 3% with repeatability of less than 1%. Determination of sulfur compounds in natural gas by gas chromatograph with sulfur chemiluminescence detector (SCD) also has many advantages, such as it is simple, fast, accurate and free from interference of most sample matrixes. The analysis method has good repeatability with lower limit of detection. Since SCD has liner equimolar response to sulfur atom, only one reference gas mixture of sulfur compound is used as external standard calibration. Determination of total sulfur content in natural gas with oxidative microcoulometry method has good repeatability and high accuracy. Determination of elemental sulfur by liquid chromatography has repeatability better than 3%, the detection limit is 10mg/m3, and recovery rate of over 90%, and is applicable for determination of elemental sulfur content in high sulfur natural gas.

Computed microtomography and numerical study of porous rock samples

Measurement of physical properties of porous geological materials is a crucial issue in oil and gas recovery industry. A conventional experimental way to obtain information on porosity, pore size distribution, specific surface area and permeability are the intrusion porosimetry and permeameter measurement. However, in this approach Washburn's equation is usually used, thus approximation of cylindrical pore shapes is made. However, in recent times the computed microtomography (CMT) technique is more widely used in geoscience (Appoloni et al., 2007). We have already reported preliminary results of investigation of elemental content, microporosity, and specific surface area of porous rocks by means of the CMT technique based on a laboratory source (Bielecki et al., 2012). In this paper, results of complex study of porous rock samples with the use of X-ray CMT (laboratory-source-based facility and synchrotron radiation source) combined with permeability tensor computation by means of the Lattice Boltzmann Method (LBM) are presented. Moreover, the proton induced X-ray emission (PIXE) method was additionally used for elemental content determination of pores-filling substance.

Reflection electron energy loss spectroscopy in Mn x Si1 − x composite structures

The dependences of the product of the electron inelastic mean free path λ and the differential cross section for inelastic electron scattering K on energy loss are determined from the experimental energy-loss spectra of the reflected electrons of MnxSi1 − x (0 ≤ x ≤ 1) composite structures. It is shown that the minimum values for the dependences of the product λK on the electron-energy loss can be used for the quantitative determination of element concentrations in this composite structure.

Quantitative Estimation of Major and Trace Elements in Coals of the Benue Trough, Nigeria

The concentrations of major and trace elements in ash residues of coals of the Benue Trough, Nigeria have been determined by electron microprobe and laser ablation-inductively coupled plasma-mass spectrometry, respectively. Major and trace element determination in rocks by fusion on an iridium strip heater followed by electron microprobe and laser ablation-inductively coupled plasma-mass spectrometry is extended here to coal ash, and the accuracy of the method is evaluated by including an Argonne Premium Coal reference sample in each analysis program. Si and Al are the major elements detected in the coal ashes. An assessment using worldwide concentration ranges of trace elements in coal ashes indicates that the Benue Trough coal ash residues are enriched in some hazardous trace elements, including Be, V, Co, and Cr. The estimated concentrations of most of the elements in the raw coals are higher than the world averages for coal. The results obtained for the Argonne Premium Coal show very good correlations with the literature and certified values, indicating that the technique described in this study can be routinely used to determine element concentrations in coals.

Particulate matter concentrations, physical characteristics and elemental composition in the Milan underground transport system

An extensive measurement campaign was conducted in the Milan subway system in order to investigate PM10 concentrations, to determine its physical and elemental composition, its origins, and to attempt to quantify source contributions. The Milan subway system includes three lines and stations typically consist of two underground levels: an intermediate floor (mezzanine) where the turnstiles for accessing the platform are located, and a platform level, one floor down. Measurements were performed in two stations for each line, and both microenvironments (platform and mezzanine) were investigated in all cases. PM10 samples were collected at all twelve sites over three daily periods for nine consecutive days at each site. Particle number concentrations were also measured with Optical Particle Counters (OPC) and size-number distributions were determined. X-ray fluorescence analysis was also performed on the samples to determine element concentrations. The results indicate PM sources related with train operations as the dominant impact on particulate concentrations. Average weekday PM10 concentrations between 105 and 283 μg m−3 were observed at the platform level, while average ambient concentrations of 36 μg m−3 were observed. Fe, Ba, Sb, Mn and Cu were found to be significantly enriched. Metal particles, occurring mostly in the range of diameters between 1 and 5 μm, and therefore likely originating from mechanical processes, account for most of the PM10 mass at the platform level. Wheel, brake and track wear are found to contribute 40–73% of total PM10 mass and electric cable wear (Cu and Zn oxides) 2%–3%. Concentrations measured on the mezzanine levels are intermediate between those found in ambient air and on the platform level, with average daytime PM10 values ranging from 50 to 80 μg m−3. The situation observed on the mezzanine can well be described through an appropriate mixing of ambient and platform level air. A decreasing, albeit still significant, impact from internal sources is observed, with particulate from wheel, brake and track wear contributing an average of 2–25%, and electric cable wear 0.5–1.2%, to total PM10 mass.

The Dietary Acrylamide Intake Adversely Affects the Serum Trace Element Status

Acrylamide is an organic chemical which occurs in foods widespreadly consumed in diets worldwide. The purpose of this study was to evaluate the serum trace element levels (Fe, Cu, Zn, Mn, Cr, Se, Co, Ni, V, As, Mg, P, Li, K, Al) in Wistar rats exposed to acrylamide. Acrylamide was administered to the treatment groups at 2 and 5 mg/kg body weight (bw)/day via drinking water for 90 days. Inductively coupled plasma mass spectrometry was used for the determination of serum trace element concentrations. Serum Zn, Se, Co, V and Mg concentrations of 5 mg/kg bw/day acrylamide-treated male rats were lower, whereas serum As concentration was higher than the same parameters of the controls rats. Similarly, serum Zn, Se, Co, V and Mg concentrations were decreased in 5 mg/kg bw/day acrylamide-treated female rats compared with control rats. On the other hand, there were no significant differences between serum Fe, Cu, Mn, Cr, Ni, P, Li, K and Al concentrations of all groups. The results from this study provide evidence that dietary acrylamide intake adversely affects the serum trace elements status.

Separate K-line contributions to fluorescence enhancement in electron probe microanalysis

The behaviour of the fluorescence enhancement correction factor in electron probe microanalysis, as a function of incident electron energy and take-off angle, is assessed for different binary samples in a wide range of compositions. Monte Carlo simulations are employed to validate Reed's correction algorithm [S.J.B. Reed, Characteristic fluorescence corrections in electron-probe microanalysis, Br. J. Appl. Phys. 16 (1965) 913-926], by means of estimating the primary excited radiation volume and the volume corresponding to secondary fluorescence generation. Then, Reed's expression for the fluorescence enhancement has been modified to account for Kα and Kβ line contributions separately. It is clearly shown that in certain cases the assignment of all fluorescent contribution to the Kα lines may be inadequate, particularly when trace element analysis imposes an accurate determination of elemental concentrations.

Nutritional value of Cymodocea nodosa and Posidonia oceanica along the western Egyptian Mediterranean coast

The nutritional value of the two seagrasses Cymodocea nodosa and Posidonia oceanica and their potential use as fertilizers were evaluated based on the determination of biochemical content, major and trace element content in the leaves of the two species, occurring in five sites along the western Egyptian Mediterranean coast during summer (2006 and 2009). The total carbohydrates, total proteins and total lipids in C. nodosa were 47.22, 510.44 and 100.78mg/g, respectively, and in P. oceanica 28.98, 607.50 and 40.50mg/g, respectively. The calorific content was 4.03Kcal/g for C. nodosa and 3.93Kcal/g for P. oceanica. N%, P2O5% and K2O% and C:N ratio were 8.45%, 1.21%, 0.81% and 1.50:1 in C. nodosa, respectively, and 10.60%, 2.13%, 0.58% and 1.25:1 in P. oceanica, respectively. The concentrations of trace elements (Cu, Ni, Pb and Zn) in the two species were lower than in composts, while the major element concentrations in C. nodosa coincided with the typical concentrations in composts (P, 530.00; Na, 1044.44; Ca, 2470.00mg/ 100g), respectively, but higher in P. oceanica (P, 930.00; Na, 2765.00; Ca, 3890.00mg/100g), respectively.Cymodocea nodosa only can be potentially used as supplementary powdered organic fertilizer and/or additive compost.

Determination of Trace Elements Content in Mineral Water and its Processed Mineral Water by ICP-MS

Determination of Trace Elements Content in Mineral Water and its Processed Mineral Water by ICP-MS

Automation of the quantitative determination of elemental content in samples using neutron activation analysis on the IBR-2 reactor at the frank laboratory for neutron physics, joint institute for nuclear research

Software for the automated quantitative determination of element concentrations in samples is described. This software is used in neutron activation analysis (NAA) at the IBR-2 reactor of the Frank Laboratory for Neutron Physics, Joint Institute for Nuclear Research (FLNP JINR).

Polarized-Beam High-Energy EDXRF in Geological Samples

ABSTRACT Certified reference materials (NIST 1645, BCR 143, IAEA 7, BCR 141, NIES_CRM_02, and IAEA 375) were used for determining the performance of a secondary target energy-dispersive X-ray fluorescence (EDXRF) spectrometer, Epsilon 5 (PANalytical, Almelo, the Netherlands). For the evaluation of the EDXRF spectra with polarized-beam high-energy excitation, the WinAxil software package has been applied. The results showed that Epsilon 5, EDXRF spectrometry is favorable for the determination of elemental concentrations in geological samples, but the sample preparation has the largest influence on the precision. However, they presented good agreement with certified values for most of the elements.

Determination of chemical elements in airborne particulate matter collected at Lembang, Indonesia by particle induced X-ray emission

Monitoring the air quality in ambient air is an important step for assessing the air pollution level in one region and its impact to the human health. In this study, the determination of chemical elements concentrations in airborne particulate matter collected in suburban area of Lembang, Indonesia was carried out. Samples were collected using a Gent stacked filter unit sampler in two size fractions of <2.5 μm (fine) and 2.5–10 μm (coarse). Sampling was conducted twice a week for 24 h from January 2008 to June 2009 and 123 pairs of samples were collected. Black carbon was determined by reflectance and chemical elements analysis were performed using particle induced X-ray emission (PIXE). PIXE as one of ion beam analysis techniques is suitable for analyzing particulate matter for its multielemental analysis with good limits of detection. Results showed that none of daily concentrations of PM2.5 and PM10 exceeded the 24 h Indonesian NAAQS for PM2.5 and PM10. Chemical elements such as Mg, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Hg and Pb were determined and the correlation between these elements was reported in order to understand the anthropogenic sources of particulate matter.

Extraterrestrial materials examined by mean of nuclear microprobe

Comet fragments, micrometeorites, and Interplanetary Dust Particles (IDPs) are small objects (<1mm) of high scientific interest in cosmochemistry. More particularly, the determination of light element concentrations, such as C and N, in cometary samples is of interest since it gives information on the regions where such materials formed. Analyses of such objects should be performed so as to extract as much information as possible while preserving sample integrity. For this purpose, we need instruments and methods that provide both microanalysis and detailed imaging. In these respects, the nuclear microprobe offers many potential advantages: (i) the spatial resolution, ∼1μm is well-matched to the typical object dimensions, (ii) with some reservations, it is non-destructive when carefully conducted, (iii) it is quantitative, and especially sensitive for light elements. At the Saclay nuclear microprobe, we have been performing analyses of extraterrestrial objects for many years. We review some of these studies, emphasizing the specific requirements for successful analyses. We also discuss the potential pitfalls that may be encountered.