The analysis of air particulate deposits using 2 MeV protons

Particle-induced X-ray emission (PIXE) analysis of the lighter elements in time-resolved air particulate deposits has been carried out. Minimum detection limits have been determined for 1.0, 2.0 and 3.5 MeVprotons. Quantitative PIXE analysis results, obtained with 2 MeV protons, are given for temporal variations in the elemental concentrations of Na, Al, Si, S, Cl, K, Ca and Fe. Rutherford backscattering (RBS) spectra were taken simultaneously with the PIXE spectra to provide information on lead concentrations and deposit thicknesses. The experimental problems associated with the quantitative analysis of light elements on cellulose acetate filters are described. The relationship between these results and meteorological data is discussed.     

Gamma-ray spectroscopic and PIXE analysis of selected samples from the phosphorite deposits of Northwestern Saudi Arabia

Phosphorite deposits from northwestern Saudi Arabia were analyzed by natural radioactivity measurements to detect the presence of radioactive elements. PIXE was used to obtain an average elemental composition of these deposits. From the analysis of radiations from ²³⁸U, ²³²Th and ⁴⁰K isotopes, the samples were found to contain U, Th and K in concentrations up to 130 ppm, 30 ppm and 2.5 wt%, respectively. PIXE showed the presence of a number of trace elements such as Ca, V, Cr, Fe, Ni, Cu, Zn, As, Sr, Y and U in concentrations ranging from a few ppm to several hundred ppm. The occurrence of these radioactive and non-radioactive elements are discussed for their geological significance in the phosphorite deposits.     

Assessment of the chemical characteristics and sources of airborne particulate matter in Santiago, Chile

Neutron activation analysis (NAA), X-ray fluorescence (XRF), proton induced X-ray emission (PIXE), atomic absorption spectrometry (AAS) and ion chromatography (IC) were used for the chemical characterization of airborne particulate matter in Santiago, Chile. The PM10 mass and elemental concentration were higher in the winter than in the summer collection period. Analytical quality assessment for NAA, XRF, PIXE, AAS and IC was performed on some samples. Correlations were found between the elements Pb–Br, Si–Ca–Fe, As–Cu–S and also between the fine mass and black carbon concentrations, which could be associated with some relevant sources.     

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 PM_2.5 and PM₁₀ exceeded the 24 h Indonesian NAAQS for PM_2.5 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.     

Removal properties of diesel exhaust particles by a dielectric barrier discharge reactor

The removal properties of diesel exhaust particles (DEP) were investigated using an engine exhaust particle size spectrometer (EEPS), field emission-type scanning electron microscopy (FE-SEM) and time-of-flight secondary ion mass spectrometry (TOF-SIMS). DEP were treated using a dielectric barrier discharge (DBD) reactor installed in the tail pipe of a diesel engine, and a model DBD reactor fed with DEP in the mixture of N(2) and O(2). When changing the experimental parameters of both the plasma conditions and the engine load conditions, we obtained characteristic information of DEP treated with plasma discharges from the particle diameter and the composition. In evaluating the model DBD reactor, it became clear that there were two types of plasma processes (reactions with active oxygen species to yield CO(2) and reactions with active nitrogen species to yield nitrogen containing compounds). Moreover, from the result of a TOF-SIMS analysis, the characteristic secondary ions, such as C(2)H(6)N(+), C(4)H(12)N(+), and C(10)H(20)N(2)(+), were strongly detected from the DEP surfaces during the plasma discharges. This indicates that the nitrogen contained hydrocarbons were generated by plasma reactions.     

Particulate matter (PM10) from São Carlos-SP (Brazil): spectroanalytical techniques to evaluate and determine chemical elements

Chemical composition of PM10 was studied during the period of 2014–2015 in the city of São Carlos, Brazil (‘Dos Voluntários’ Square). PM10 samples were directly analysed by wavelength dispersive X-ray fluorescence – WD-XRF (Al, Ca, Ce, Cl, Fe, K, Mg, P, S, Si, Ti, V, and Zn), and by laser-induced breakdown spectroscopy – LIBS (Ba, Ca, Fe, K, Mg, Na, Si and Ti) both for qualitative purposes. For quantitative analysis of Al, Ba, Ca, Fe, K, Na, S, and Zn, the analytes were extracted from samples of PM10 collected, in filters of glass fibre, with an extractive acid solution (HNO₃ and HCl) and determined by inductively coupled plasma optical emission spectrometry – ICP OES. Spatial variations of elemental concentrations (ng m^–3) were significantly higher in winter Al (19.0), Ba (13.6), Ca (20.0), Na (27.0), S (37.1), and Zn (9.5), autumn showed the highest concentration of Na (26.4), spring showed the highest concentration of Fe (11.6), K (13.1) and also S (25.3) and summer did not show a high concentration in the comparison between the seasons at the site. Using principal component analysis (PCA), as a data interpretation tool, with the data obtained by the WD-XRF and LIBS it was not possible to obtain a good correlation, but with the data of ICP OES, it was possible to verify correlations between identified and determinate elements, with samples collected in the autumn, winter, spring and summer seasons in the city of São Carlos. These associated analytical techniques were excellent tools in environmental monitoring, through the analysis of PM10 samples, presenting reliable and efficiency strategy, and based on the PCA and the EF equation was possible to draw the profile of the possible origins of these elements in the city.     

Inorganic species in water and sediments of the Lamone and Marzeno rivers ecosystem

Analytical results are reported for the determination of inorganic species in water and sediments sampled in the Lamone and Marzeno rivers ecosystem. The species determined are Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Zn, Hg, F-, Cl- Br-, NO3-, SO4--, Na+, K+, Mg++, Ca++, NH4+ in superficial water, and Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Zn, Hg in sediments. For all the elements, in addition to detection limits, precision and accuracy are given: the former, expressed as relative standard deviation (s(r)), and the latter, expressed as relative error (e), were good, being in all cases lower than 6%.     

Study of seasonal variation and source characteristic of PM10 of Shanghai urban atmosphere using PIXE

This study is a one-year monitoring of the inhalable particulate matter (PM10) of Shanghai (from January 2006 to December 2006) to study PM10 pollution. Proton-induced X-ray emission (PIXE) was used to investigate the chemical elements in Shanghai PM10. The study finds seasonal variation in both mass concentration and of chemical elements in PM10. The results of the enrichment factor show that the chemical elements in the inhalable particles could be divided into two categories, soil elements from earth crust and anthropogenic pollution elements. The high enrichment factors suggest that anthropogenic activities were the dominant source for elements such as S, Cu, Cl, Zn, Pb and Br. Strong correlation of K, Ca, Fe and Ti, from factor analysis, indicates these elements coming from earth crust or soil, S, Zn and Pb from industrial pollution and/or traffic and Cl from coal combustion.     

Dating and classification of Syrian excavated pottery from Tell Saka Site,by means of thermoluminescence analysis,and multivariate statistical methods,based on PIXE analysis

Thermoluminescence (TL) dating and Proton Induced X-ray Emission (PIXE) techniques have been utilized for the study of archaeological pottery fragment samples from Tell Saka Site, which is located at 25 km south east of Damascus city, Syria. Four samples were chosen randomly from the site, two from third level and two from fourth level for dating using TL technique and the results were in good agreement with the date assigned by archaeologists. Twenty-eight sherds were analyzed using PIXE technique in order to identify and characterize the elemental composition of pottery excavated from third and fourth levels, using 3 MV tandem accelerator in Damascus. The analysis provided almost 20 elements (Na, Mg, Al, Si, P, S, K, Ca, Ti, Mn, Fe, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb). However, only 14 elements as follows: K, Ca, Ti, Mn, Fe, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb were chosen for statistical analysis and have been processed using two multivariate statistical methods, Cluster and Factor analysis. The studied pottery were classify into two well defined groups.     

Elemental content of erythrocytes from patients undergoing Coronary Artery Bypass Grafting (CABG) surgery using PIXE analysis

Summary This on-going study was conducted on erythrocytes to further establish the content of elements of blood fractions from patients undergoing Coronary Artery Bypass Grafting (CABG) surgery. As the quality and quantity of elements in these samples were unknown, proton induced X-ray emission (PIXE) analysis was chosen for its multi-elemental analysis capabilities on small mass samples. Previous work demonstrated the detection of several elements using PIXE analysis and that the elemental concentrations of S, Cl, Ca and Fe were worthy of note. It is indicated that continuing analysis of these cell fractions may be significant in the study of trace element metabolism as it provides insight into understanding mechanisms for preventative, diagnostic and therapeutic purposes and hence a patient's state of health. The analysis of erythrocytes was conducted at pre, during and post-operative timepoints to investigate the changes that occur during and post-surgical intervention. Elements Na, Mg, Si, P, S, Cl, K, Ca, Fe, Cu, Zn, Br and Rb were detected in erythrocytes at all surgery timepoints and from normalized graphs, elements S, K and Fe revealed that the changes in concentration through surgery followed an almost identical pattern. It is anticipated that statistical correlation and interpretation of data may provide, in the long-term, information that could have an impact on the patients' rate of recovery or appropriate aftercare.     

Element concentrations in hair of children living in environmentally degraded districts of the East Aral Sea region

Environmental conditions were evaluated by element concentrations in hair of children living near the Aral Sea. Hair samples were provided by 63 children living near the Sea (K-district), and 143 children living about 600 km from the Sea (Z-district). PIXE was applied for the determination of elemental concentrations. The concentrations of Br, Na, Hg, and Ni were higher in K-district, and those of Al, Ca, Cr, P, S, and Si were higher in Z-district than in the other district, respectively. It is considered that these results reflect the environmental situation.     

Simultaneous PIXE and PIGME Analysis of a Nigerian Tar Sand Sample from a Deep Borehole

Tar sands from a deep borehole in southwestern Nigeria were subjected to elemental analysis by simultaneous proton induced X-ray emission (PIXE) and proton induced gamma-ray emission (PIGME) techniques. The concentration of 22 major, minor and trace elements, namely Al, Ca, Cr, Cu, F, Fe, Ga, Ge, K, Li, Mg, Mn, Na, P, Pb, Rb, S, Si, Sr, Ti, Zn and Zr were determined. The accuracy and precision of the techniques for chemical analysis were assured by analysing the NBS 278 geological standard.     

Neutron activation analysis: Still a reference method for air particulate matter measurements

At ITN, PM10 and PM2.5 aerosols were collected on Nuclepore^® polycarbonate filters of 47 mm diameter, using Gent samplers at 15–17 l/min air flux. Filters were analyzed by INAA and PIXE. The availability of certified filters was very scarce, viz.: (1) fly ash embedded in a methyl cellulose 47 mm foil 10 µm thick, BCR CRM128, (2) particle-size reduced air particulate matter (APM) to simulate PM2.5 aerosol matter deposited on a 47 mm polycarbonate filter membrane, NIST SRM 2783. The high price and scarcity of APM standards did not permit their frequent use for analytical quality control. At ITN, to control the filter results' accuracy, the chemical elements potassium, iron and zinc, determined by both techniques, were systematically compared. After a few improvements introduced in INAA, this technique was now considered at ITN as the reference technique in air particulate measurements. Comparison of INAA to PIXE was discussed. Compared to previously reported situation it was concluded that the results were in better agreement for iron and zinc, and potassium values were still biased to the same extent as before.     

Modeling of ionic equilibria of trace metals (Cu2+, Zn2+, Cd2+) in concentrated aqueous electrolyte solutions at 25 degrees C

This work presents a model of activity coefficients and a database for ionic equilibria of Cu2+, Zn2+, and Cd2+ in (H+, Na+, K+, Mg2+, Ca2+)(OH-, Cl-, NO-3, ClO-4, HSO-4, SO2-(4), HCO-3, CO(2-)3) aqueous media valid up to 6-12 m ionic strength. The activity coefficient of a dissolved species is represented by empirical equation [Formula: see text] , where Agamma is Debye-Hückel constant (1.17 at 25 degrees C), gammai and zi are activity coefficient and charge of a dissolved species i, I is molal ionic strength, bij is model parameter, and mj is molal concentration of dissolved species. The model is applicable to the modeling of ionic equilibria, as well as to simulation of solubility of salts in mixed electrolyte solutions.     

Electrophoretic mobility, zeta potential, and fixed charge density of bovine knee chondrocytes, methyl methacrylate-sulfopropyl methacrylate, polybutylcyanoacrylate, and solid lipid nanoparticles

The electrophoretic mobility and zeta potential of bovine knee chondrocytes (BKCs), methyl methacrylate-sulfopropyl methacrylate (MMA-SPM) nanoparticles (NPs), polybutylcyanoacrylate (PBCA) NPs, and solid lipid nanoparticles (SLNs) were investigated under the influences of Na+, K+, and Ca2+ with various ionic strengths. The fixed charge density in the surface layers of the four biocolloidal particles was estimated from the experimental mobility of capillary electrophoresis with a theory of soft charged colloids. The results revealed that, for a specific cationic species, the absolute values of the electrophoretic mobility, the zeta potential, and the fixed charge density decreased with an increase in ionic strength. For a constant ionic strength, the effect of ionic species on the reduction in the absolute values of the electrophoretic mobility, the zeta potential, and the fixed charge density followed the order Na+>K+>Ca2+ for the negatively charged BKCs, MMA-SPM NPs, and SLNs. The reverse order is true for the positively charged PBCA NPs.     

Elemental analysis of the frontal lobe of “normal” brain tissue and that affected by Alzheimer's disease

Normal brain tissue and brain tissue affected by Alzheimer's disease has been taken from the frontal lobe of both hemispheres and their elemental compositions in terms of major, minor and trace elements compared. Brain samples were obtained from the MRC Alzheimer's Disease Brain Bank, London. 25 samples were taken from 18 individuals (5 males and 13 females) of mean age 79.9±7.3 years with pathologically confirmed Alzheimer'sdisease and 26 samples from 15 individuals (8 males and 7 females) of mean age 71.8±13.0 years with no pathological signs of Alzheimer's disease (normals). The elemental concentration of the samples were determined by the techniques of Rutherford backscattering (RBS) analysis, particle induced X-ray emission (PIXE) analysis and instrumental neutron activation analysis (INAA). Na, Mg, Al, Cl, K, Sc, Fe, Zn, Se, Br, Rb and Cs were detected by INAA and significant differences in concentrations were found between concentrations in normal and Alzheimer tissue for the elements. Na, Cl, K, Se, Br and Rb, P, S, Cl, K, Ca, Fe, Zn and Cd were detected by PIXE analysis and significant differences found for the elements P, S, Cl, K and Ca.     

Characterization of airborne particulate matter collected at Jakarta roadside of an arterial road

A total of 44 pairs of airborne particulate matter samples were collected in the intersection of Simprug, Pondok Indah, South Jakarta. Sampling of airborne particulate matter was conducted in July 2008–July 2009 using a Gent stacked filter unit sampler in two size fractions of <2.5 µm (fine) and 2.5–10 µm (coarse). Mass concentrations, black carbon as well as elemental concentrations were investigated as a pre-study in step to the evaluation of air quality in these roadside areas. Black carbon was determined by reflectance and elemental analysis was performed using proton induced X-ray emission, PIXE. The data set of fine particulate matters obtained from the characterization was then analyzed using receptor modeling EPA PMF3 for source apportionment. Source apportionment identified 5 factors, i.e. soil (9.2 %), construction mixed with road dust (20.9 %), motor vehicles (31.5 %), biomass burning mixed with seasalt (30.9 %), and industry (7.5 %). Motor vehicles is the dominant sources that contributes to the fine particulate matter in Jakarta.     

铊(I)离子选择电极动力学分析法测定超痕量铁

Fe(II) induces the reaction between Tl3+ and H2O2. The rate of reaction is linearly proportional to the concentration of Fe2+ in the range 2.5 ?10-9-2.5 ?10-8 mol dm-3 (20? and 5 ?10-9-5 ?10-8 mol dm-3 (15?. The standard deviation is less than 0.071 ?10-8. A 1000-fold excess of Zn2+, Cd2+, Mg2+, Ni2+, Pb2+, Ba2+, Ca2+, Li+, Na+, Ag+, NO3-, SO42-, AcO-, HPO42-, 500-fold excess of Al3+, Fe3+, Co2+, Hg2+ and 100-fold excess of Ti4+, Cr3+, Cu2+, Br-, Cl- can be tolerated, but reducing agents such as (NH2)2SO4, NH2OH.HCl interfered. This kinetic method was applied to determine Fe(II) in standard zinc sample and fountain water, with satisfactory results.     

Assessment of trace elements characteristics and human health risk of exposure to ambient PM2.5 in Hangzhou,China

A method for simultaneously determining the trace elements in particulate matter (PM) (PM2.5) by inductively coupled plasma mass spectrometry was established. The PM2.5-loaded filter samples were digested under the optimised conditions including a mixture of HNO₃–HCl–HF with ultrasonication proceeding at 70°C for 2 h. Recoveries of 90.83–103.33% were achieved for 20 elements (Co, Sr, Ag, Cd, Sb, La, Ce, Sm, W etc.) in NIST standard reference material 1648a (urban PM). PM2.5 samples were collected at urban site in Hangzhou from August 2015 to November 2015. PM2.5 concentrations of 15% sampling days exceeded the daily limitation and the mean concentrations of PM2.5 from August to November reached the 66.4% of the limitation. PM2.5 concentrations in summer were higher than that in autumn. The concentration of Zn was highest, following with Al, Pb, Mn, Cu and As. Significant enrichment was observed in Mn, Zn, Pb, Ag, V, Ni, Cu, As, Se, Hg, Co, Cd and W, which was probably induced by vehicular exhaust, oil and residual fuel combustion and industrial emissions. The daily mass concentrations of PM2.5 and elements fluctuated significantly. Rainfall could significantly reduce the concentration of Ti, Mn, Cu, Zn, As, Se, Hg, Sr, Ag, Cd, Sb, La, Ce, Sm and Pb, and the risk levels of carcinogenic elements and non-carcinogenic elements in rain day were significantly lower (43.7–81.4%) than those in non-rain day. The risk levels of Co, Cd and As could lead to adverse health outcomes through the respiratory system, which should deserve more attention, while the risk levels of Ni and non-carcinogenic elements (Hg, Mn, Cu, Zn, Pb, V) were under average risk acceptance.     

Multielement analysis of green coffee and its possible use for the determination of origin

Using instrumental neutron activation analysis (INAA), graphite furnace atomic absorption spectrometry (GFAAS), flame atomic absorption spectrometry (FAAS) and combustion elemental analysis, green coffees of the Arabica species produced in crop year 1987/88 in Colombia, Costa Rica, Cuba, El Salvador, Mexico, Nicaragua, Panamá and Papua New Guinea were analysed for the elements Ba, Br, C, Ca, Co, Cr, Cu, Cs, Fe, H, K, La, Mg, Mn, N, Na, Rb, Sc, Sr and Zn. In accordance with the concentrations determined, the elements could be ranked into five groups: Sc (sub-ppb level); Br, Co, Cr, Cs and La (ppb level); Ba, Cu, Fe, Mn, Na, Rb, Sr and Zn (ppm level); Ca and Mg (%o level); and C, H, K and N (% level). On the basis of the results obtained, an attempt was made to establish the origin of the green coffee via its elemental composition. Among the investigated elements, manganese was found to be best suited as an indicator for this purpose. However, the elements C, Co, Cs, Na and Rb proved to be of interest too.