Decationization and dealumination of clinoptilolite tuff and ammonium exchange on acid-modified tuff

The paper presents results of investigation of exchange of the clinoptilolite tuff cations with hydrogen ions from HCl solution of concentration 0.1 mmol cm(-3) and ammonium ions solutions of concentrations 0.0071 to 2.6 mmol cm(-3). Molal concentrations, x (mmol g(-1)) of cations exchanged in acid solution and in ammonium ions solutions were compared with molal concentrations of cations obtained by determination of the cation-exchange capacity of clinoptilolite tuff. The obtained results show that at ammonium ion concentrations lower than 0.1 mmol cm(-3), with regard to exchange capacity for particular ions, best exchanged are Na+ ions, followed by Mg2+ and Ca2+ ions, while exchange of K+ ions is the poorest (Na+ > Mg2+ > Ca2+ > K+). At ammonium concentrations from 0.2 to 1 mmol cm(-3) the order is Na+ > Ca2+ > Mg2+ > K+. At concentrations higher than 1 mmol cm(-3) the order is Na+ > Ca2+ > K+ > Mg2+. The results are a consequence of the uptake of hydrogen ions by zeolite samples in ammonium ions solutions at concentrations lower than 1 mmol cm(-3) and indicate the importance of Mg2+ (besides Na+ ions) for the exchange between clinoptilolite cations and H+ ions, in contrast to K+ ions, whose participation in the reaction with H+ ions is the lowest. During decationization of the clinoptilolite in acid solution, best exchanged are Na+, Mg2+, and Ca2+ ions, while exchange of K+ ions is the poorest. Due to poor exchange of K+ and H+ ions and good exchange of Na+, Mg2+, and Ca2+ ions, it is to be assumed that preservation of stability of the clinoptilolite structure is caused by K+ ions present in the channel C. Clinoptilolite is dissolved in the clinoptilolite A and B channels where Na+, Mg2+, and Ca2+ ions are present. On the acid-modified clinoptilolite samples, exchange of ammonium ions is poorer than on natural zeolite. The longer the contact time of the zeolite and acid solution, the worse ammonium ions exchange. It can be assumed that H+ ions exchanged with zeolite cations are consumed for solution of aluminum in the clinoptilolite structure; therefore the concentration of H+ ions as exchangeable cations decreases. In the ammonium ion solution at a concentration of 0.0065 mmol cm(-3), from the acid-modified zeolite samples, Al3+ ions are exchanged best, followed by Na+, Mg2+, Ca2+, and K+ ions. Further to the results, it is to be assumed that exchangeable Al3+ ions available from clinoptilolite dissolution are best exchanged with H+ ions in acid solution.     

Inter-annual variability in atmospheric input and partitioning of heavy metals in the Lagoon of Venice

Atmospheric bulk deposition of major and trace elements was measured at Venice from November 1995 to October 1997. Collection was carried out using polyethylene bulk passive samplers, samples being collected bi-weekly. In order to highlight the contribution of the atmosphere to water chemistry and particle budgets in the Lagoon of Venice, the geochemical composition (Si, Al, Ca, Mg, K, Na, Mn, Cr, Zn, Pb, Cd, Cu, As) of dissolved and insoluble bulk fractions was determined by AAS + ICP mass spectrometry. Great sample variability was found, with almost two orders of magnitude between maximum and minimum values for several metals. All fluxes in 1995/96 were 30% lower than in 1996/97, ranging from -3% (Ca) to -57% (Li), except for Zn, Cd and As. On the contrary, the solubility of all elements decreased during 1996/97. Partitioning between soluble and insoluble phases shows that Al, Cr, Fe and Si are mainly in the insoluble form, whereas for As, Ca, Cu, Mg, Na, Ni, K, Pb and Zn the dissolved fraction represents 50-90% of total input. The amount of particle load affects partitioning between dissolved and particulate, especially for Al and Pb. Seasonal variability was evident. The lowest pH values (approximately 5.2) were recorded in winter, causing an increase of solubility for all metals except for As, which showed the highest solubility in summer.     

Multivariate analysis of trace elements determined in archaeological materials and its use for characterisation

Data on the concentrations of K, Ca, Ti, Fe, Cu, Zn, Ga, Rb, Sr and Zr obtained by PIXE and of B, F, Na, Mg, Al, Si and Cu obtained by proton-induced prompt gamma-ray spectrometry were used to characterize archaeological artefacts and source materials by multivariate analysis. The mathematical approaches employed were cluster analysis using nearest-neighbour data, multidimensional scaling and correspondence analysis.     

Multi-elemental profile patterns during the life cycle stage of the soybean Part 1. Determination of representative elements, Na, Mg, Al, K and Ca

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.     

电感耦合等离子体原子发射光谱法（ICP-AES）测定花生仁和黄豆中多种元素

采用ICP-AES法对通辽地区产的花生仁和黄豆中Na,K,Mg,Ca,P,Fe,Cu,Mn,Zn,Sn,Al和Si等元素的含量同时进行测定。回归方程的相关系数为0.999 2~0.999 8,相应各元素的检出限范围为0.25~97.03μg/L,加标回收率和相对标准偏差范围分别为91.23%~108.60%和0.69%~3.3%,实验建立了简便、快速和稳定的测定花生仁和黄豆中元素含量的方法。结果显示在花生仁和黄豆中P含量非常高,黄豆中Ca,Mg,Fe,Zn和Sn的含量较花生仁中的较高。     

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.     

Ion-exchange separation and atomic-absorption determination of fifteen major, minor and trace elements in silicates

A scheme of ion-exchange separation of fifteen elements (major, minor and trace) determined mainly by atomic-absorption spectrophotometry (Ti by colorimetry) is applied to rock, mineral and ceramic analysis. Mn, Cu, Co, Fe and Zn are separated on an anion-exchanger and Li, Na, K, Mg, Ca, Sr, Ti, Al, Ni and Ba on a cation-exchanger. The method has been tested by analysis of a synthetic mixture of the fifteen ions in the ratios in common rock samples, and of various international standards (100-mg samples).     

Collection efficiency of metallic contaminants on si wafer by vapor-phase decomposition-droplet collection.

The collection efficiency of metallic contaminants on four different types of silicon wafers was investigated. P, p+, n and n(+)-type polished silicon wafers were used for the substrate, and 14 metallic elements (Na, Mg, Al, K, Ca, Cr, Fe, Mn, Co, Ni, Cu, Zn, Mo and Ti) were contaminated on silicon wafer surface. Vapor-phase decomposition-droplet collection (VPD-DC) was employed as the sample preparation procedure. For the collecting solution, HNO3, HF and a mixture of HF and H2O2 were used, respectively. A liquid droplet collecting metallic contaminants during VPD-DC was analyzed by inductively coupled plasma-mass spectrometry (ICP-MS). As a result, it was found that HNO3 and HF were not suitable for collecting Cu. Copper was not collected completely in HNO3 and HF. A mixture of HF and H2O2 is the most effective to collect all of the tested metallic elements, regardless of the dopant concentration and type of substrate.     

电感耦合等离子体原子发射光谱法(ICP-AES)测定黄禾和谷子中15种元素

提出了用电感耦合等离子体原子发射光谱法对通辽地区产黄禾和谷子中Na,Ca,Sn,Cu,Zn,Al,Mg,Fe,P,Si,K,Ba,Se,Mo,Mn 15种元素含量同时进行测定的方法,并对各元素作了加标回收实验,黄禾和谷子中各元素的平均回收率为96.67%~104.00%,相对标准偏差RSD均小于5%。方法简便、快速、准确地测定了黄禾和谷子中的元素。结果显示,在黄禾和谷子中K,P,Mg含量高,谷子中Ca,Mg,Fe,Zn和Mn的含量较黄禾中的高。黄禾和谷子中富含丰富的Na,Ca,Zn,Fe等元素,从微量元素角度看谷子中对身体有益的元素较黄禾高。     

Study on mineral surface reacted with water at temperatures above 300��C and 23?MPa

In this work, we carried out experiments on silicate mineral dissolution using a flow-through reactor from 20 to 400°C at 23 MPa. The dissolution of silicate minerals such as actinolite, diopside, and albite in water may require the breaking of more than one metal?Coxygen bond type. Different metal elements in silicate minerals have different release rates and the dissolution product is often non-stoichiometric. Na, Mg, Fe, and Ca dissolve faster than Si at T < 300°C. At T ?? 300°C, the release rate of Si is higher than that of the other metals. The molar concentration ratios of the dissolving metal Mi versus Si such as Mg/Si, Ca/Si and Al/Si, which are the release ratios in the effluent solutions, are often different from the molar ratios of these elements in the minerals. The results show that the incongruent dissolution of minerals is related to surface chemical modifications. Non-stoichiometric dissolution is caused by the formation of a non-stoichiometric leaching layer at the surface or by the presence of a secondary mineral at the surface. Our experiments indicate that the dissolution of most silicate minerals is close to stoichiometric at 200 and 300°C, e.g., for actinolite and albite at 300°C. The surfaces after reaction with aqueous solutions were investigated using SEM and TEM. At T < 300°C, the mineral surfaces (e.g., for actinolite) after the reaction with water are slightly Si-rich and slightly Fe (and/or Mg, Ca) deficient. In contrast, at T ?? 300°C, the surfaces after reaction with water are slightly Fe-rich and somewhat Si deficient.     

Study of Ca-ATMP precipitation in the presence of magnesium ion

ATMP (aminotri(methylenephosphonic acid)), a phosphonate scale inhibitor used in the petroleum industry, was used as a model scale inhibitor in this study. One of the goals of this work was to determine the range of conditions under which Mg ions, which are formed in reservoir formations containing dolomite, modulate the formation of Ca-ATMP precipitate as a scale inhibitor. The results revealed that the amount of ATMP precipitated decreased with addition of Mg ions in solution at all values of the solution pH. Furthermore, an increase in both the solution pH and the concentration of the divalent cations in solution resulted in a change of the molar ratio of (Ca + Mg) to ATMP in the precipitates. At a low solution pH (pH 1.5), Mg ions had little effect on the composition of the Ca-ATMP precipitate. However, at higher values of the solution pH (pH 4 and 7), the Ca to ATMP molar ratio in the precipitates decreased with increasing concentration of the Mg. Here it was found that Mg ions replaced Ca ions on available reactive sites of ATMP molecules. These results determined the limits of the Mg ion concentration, which affects the precipitation of Ca-ATMP, Mg-ATMP, and (Ca + Mg)-ATMP. The dissolution of the scale inhibitors was studied using a rotating disk reactor. These experiments showed that the total divalent cation molar ratio (Ca + Mg) to ATMP in the precipitates is the primary factor that controls the rate of dissolution (release) of the phosphonate precipitates. The phosphonate precipitate dissolution rates decreased as the molar ratio of divalent cations to ATMP in the precipitates increased.     

电感耦合等离子体发射光谱法(ICP-AES)测定黄禾和谷子中15种元素

摘 要：提出了用等离子体发射光谱对通辽地区产黄禾和谷子中Na,Ca,Sn,Cu,Zn,Al,Mg,Fe,P,Si,K,Ba,Se,Mo,Mn 15种元素含量同时进行测定的方法,并对各元素作了加标回收实验,黄禾和谷子中各元素的平均回收率为96.67%～104.00%,RSD为0.78%～2.86%。方法简便、快速、准确地测定了黄禾和谷子中的元素。结果显示,在黄禾和谷子中K,P,Mg含量高,谷子中Ca,Mg,Fe,Zn和Mn的含量较黄禾中的高。黄禾和谷子中富含丰富的Na,Ca,Zn,Fe等元素,从微量元素角度看谷子中对身体有益的元素较黄禾高。     

Assessment of metal contamination in an urban drainage system (using water and tilapia, Oreochromis spp.) in view of human health effect. A case study of some selected communities in Cape Coast township in Ghana

This research work aimed at studying the metal content of water and tilapia fish sample, Oreochromis spp., from a wastewater-fed pond around the University of Cape Coast community using instrumental neutron activation analysis. The metals studied were Al, As, Ca, Co, Cr, Cu, Fe, K, Mg, Mn, Na, V and Zn. In the water samples the order of elemental concentrations at sampling point 1, in ??g/g, was K (75.96?±?0.92), Na (18.52?±?0.35), Al (6.00?±?0.89), Mn (3.28?±?0.44), As (3.08?±?0.40), Mg (1.56?±?0.17), Ca (0.70?±?0.08), Cu (0.54?±?0.08) and V (0.04?±?0.01). Co, Cr, Fe and Zn were below detection limits of INAA. The order of elemental concentrations in the water at point 2 was as follows: Na (4.99?±?0.14), K (4.82?±?0.89), Mn (4.40?±?0.53), Mg (2.92?±?0.37), Al (1.98?±?0.21), As (0.69?±?0.10), Ca (0.24?±?0.07) and V (0.23?±?0.06) with Co, Cr, Cu, Fe and Zn falling below the detection limit of INAA. The concentrations recorded for Al, As, Cu and Mn in the water samples were all above WHO permissible limits. The mean levels of heavy metals in the soft tissue of tilapia was of the order: K?>?Mg?>?Fe?>?Ca?>?Na?>?Al?>?Mn?>?Zn?>?V?>?Cu?>?Cr?>?Co. Arsenic was below detection limit. The transfer factor values calculated for the metals Al, Ca, K, Mg, Mn, Na and V were all greater than one indicating movement of metals from the water column to the tilapia species. The hazard index (HI) calculated for Al, Fe, Mn and V suggested possible occurrence of adverse health effects (HI?>?1) where as the HI value obtained for Cr, Cu and Zn (i.e., HI?<?1) suggested unlikely adverse effects occurring.     

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.     

Application of nondestructive X-ray fluorescence analysis to determine the element composition of medicinal plants

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.     

Application of neutron activation analysis in acid precipitation studies

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).     

The analysis of archaeological glass by inductively coupled plasma optical emission spectroscopy

Summary An analytical procedure is described for the analysis of archaeological glass by inductively coupled plasma optical emission spectroscopy (ICP-OES). Glass samples were analysed in solution after fusion with lithium metaborate at 1100°C. The analyses were performed in the sequential multielemental mode of operation, with the determination of 15 elements in four analytical runs; only elements with not too large concentration difference were analysed in a single run. The following elements were accounted for: Si, Na, Ca, Al, Fe, Mg, Mn, Ti, Sr, Ba, Cr, Ni, Cu, Co, Pb.     

尿毒症患者与血清八种元素含量关系的研究

检测了３７例尿毒症患者血清微量元素Ｆｅ、Ｃｕ、Ｚｎ和常量元素Ｋ、Ｎａ、Ｃａ、Ｍｇ、Ｐ的含量，并进行比较，探讨其相互关系，以期为尿毒症的发生发展及防治措施提供依据．结果发现尿毒症患者血清Ｋ、Ｐ、Ｍｇ极显著高于对照组（均Ｐ＜０．０１），而Ｎａ、Ｃａ、Ｚｎ、Ｃｕ、Ｆｅ及Ｎａ／Ｋ、Ｃａ／Ｍｇ则极显著低于对照组（均Ｐ＜０．０１），且Ｎａ／Ｋ、Ｃａ／Ｍｇ与肾实质受损程度呈负相关，提示Ｎａ／Ｋ、Ｃａ／Ｍｇ降低与尿毒症的发生发展过程有密切的关系．     

Characterization of Polish rape and honeydew honey according to their mineral contents using ICP-MS and F-AAS/AES

In this work twelve elements (Al, B, Ca, Cr, Cu, Fe, K, Mg, Mn, Na, Ni and Zn) were determined in 30 honey samples from various locations within Poland and in two different types of honey--rape and honeydew. Trace elements (Al, B, Cr, Mn and Ni) were determined by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS), however, major elements (Ca, K, Mg, Na) and Cu, Fe, Zn were determined by Flame Atomic Absorption Spectrometry (F-AAS). Cluster analysis of honey data revealed that the origin of honey samples correlated with their chemical composition. It was shown that rape honey includes lower amounts of manganese than honeydew honeys. Also honeydew honey includes much higher concentrations of Al, Cu, K, Fe and Ni in comparison with rape honey. Moreover honeydew honey was found to have a higher mineral content, which reflects sources from which the honey is composed. Trace element analysis showed that the differences in the values found in honey samples could be used as evidence of the quality of honey samples.