Simultaneous determination of low Z elements in barium borosilicate glass samples by in situ current normalized particle induced gamma-ray emission methods

Particle induced gamma-ray emission (PIGE) method using 4 MeV proton beam was utilized to analyze two types of barium borosilicate glass (BaBSG) samples for quantification of concentrations of low Z elements. The in situ current normalization method was applied in the analysis of eight samples containing varying concentration of F along with Si, B and Na. Charge normalized PIGE method was applied to determine concentrations of above low Z elements including Li and Al in samples having simulated nuclear waste from reprocessing of thoria spent fuel. Synthetic samples and NIST SRMs were used for method validation.     

Characterization of simulated vitrified highly active waste and its leachates by neutron activation

Neutron activation analysis (NAA) methods have been developed for the simultaneous determinations of multielement concentrations in various types of glass and their leachates. The epithermal instrumental NAA (EINAA) method involves the irradiation of samples in a Cd-shielded site for 2–5 min in order to determine levels of of up to 13 elements through their short-lived nuclides. Another 15 elements can be measured via their long-lived nuclides using conventional instrumental NAA (INAA). Accuracy of the methods have been evaluated by analyzing certified reference materials. The limits of detection for all elements are reported. The methods have been applied to sodium borosilicate and sodium calcium aluminosilicate glass samples in order evaluate their suitability as a host matrix for immobilizing high level radioactive waste.     

Distribution of 35 elements in peat cores from ombrotrophic bogs studied by epithermal neutron activation analysis

Summary In ombrotrophic bogs the surface peat layer is supplied with chemical substances only from the atmosphere. Therefore, peat cores from these bogs can be used to study temporal trends in atmospheric deposition of pollutants. In this work epithermal neutron activation analysis was applied for the first time to study the distribution of 35 elements in peat profiles from ombrotrophic bogs. The selected samples were from Finnmark county in northern Norway, one pristine site far from any local pollution source, and the other samples from strongly affected by long-term operation of a Russian copper-nickel smelters located close to the border. The elements are classified with respect to their behavior in the uppermost 40 cm of the peat, and similarities and differences between the two profiles are discussed. As compared with other more commonly used analytical techniques based on acid decomposition of the sample, ENAA has the advantage of providing the total concentrations of the elements.     

Analysis of urban dust (PM<Subscript>2</Subscript>/PM<Subscript>10-2</Subscript>) in Daejeon city by instrumental neutron activation analysis

Summary As part of an air pollution monitoring study, airborne particulate matter (PM₂/PM_10-2) samples were collected from 2000 to 2003 at two sampling sites in an urban region, Daejeon, the middle of Korea. Mass concentrations of both fine and coarse fractions and that of the black carbon in the fine particles were measured using the Gent stacked filter unit sampler and the smoke stain reflectometer, respectively. In the collected samples the concentrations of 24 elements were analyzed using instrumental neutron activation analysis. Monitored data were investigated for their temporal trends under different environmental conditions and their seasonal correlation patterns. Crustal enrichment factors were also estimated to establish the contribution between anthropogenic and crustal origin. Patterns for airborne particle matter (APM) and elemental concentrations, seasonal variation of some marker elements were investigated. The results can be applied for the investigation of further air pollution sources and for the evaluation of air quality.     

XRF and TXRF techniques for multi-element determination of trace elements in whole blood and human hair samples

XRF and TXRF were established as useful techniques for multi-element analysis of whole blood and human head hair samples. Direct-XRF with different collimation units and different X-ray excitation modes was successfully used for the determination of S, P, K, Ca, Fe, and Br elements in blood samples and K, Ca, Mn, Fe elements in human hair samples. Direct analysis by TXRF was used for the determination of Rb and Sr in digested blood and human hair samples, respectively, while, the co-precipitation method using APDC for TXRF analysis was used for the determination of Ni, Cu, Zn, and Pb elements in both matrices. As a result, the improved XRF and TXRF methods were applied for multi-element determination of elements in whole blood and human hair samples in non-occupational exposed population living in Damascus city. The mean concentrations of analyzed elements in both matrices were on the reported range values for non-occupational population in other countries.     

Analysis of elemental concentration censored distributions in breast malignant and breast benign neoplasm tissues

The total reflection X-ray fluorescence method was applied to study the trace element concentrations in human breast malignant and breast benign neoplasm tissues taken from the women who were patients of Holycross Cancer Centre in Kielce (Poland). These investigations were mainly focused on the development of new possibilities of cancer diagnosis and therapy monitoring. This systematic comparative study was based on relatively large (∼ 100) population studied, namely 26 samples of breast malignant and 68 samples of breast benign neoplasm tissues. The concentrations, being in the range from a few ppb to 0.1%, were determined for thirteen elements (from P to Pb). The results were carefully analysed to investigate the concentration distribution of trace elements in the studied samples. The measurements of concentration of trace elements by total reflection X-ray fluorescence were limited, however, by the detection limit of the method. It was observed that for more than 50% of elements determined, the concentrations were not measured in all samples. These incomplete measurements were treated within the statistical concept called left-random censoring and for the estimation of the mean value and median of censored concentration distributions, the Kaplan–Meier estimator was used. For comparison of concentrations in two populations, the log-rank test was applied, which allows to compare the censored total reflection X-ray fluorescence data. Found statistically significant differences are discussed in more details. It is noted that described data analysis procedures should be the standard tool to analyze the censored concentrations of trace elements analysed by X-ray fluorescence methods.     

A provenance study of coffee by photon activation analysis

Photon activation analysis (PAA) is a multi-elemental radioanalytical technique in trace elements analysis with high accuracy and precision. Researchers at the Idaho accelerator center performed PAA analysis on coffee samples from several locations around the world as an initial step in assessing the relationship between trace elements in illicit drugs and the soils in which they were grown. The preliminary results show coffees from different locations have different concentrations of trace elements. In the three cases where we have soil samples, the matrices of elements in the coffee samples are closely related to the matrices of the elements of the local soil samples. The majority of trace elemental content is similar to that of the local soil sample in which the coffee is planted. It may be that coffee assimilates numerous elements from the soil where it is grown in similar ratios as is found in the soil. Thus, it is conceivable that the elemental content could serve as “fingerprint” to trace the origins of the coffee. To verify our analytical results we applied X-ray fluorescence (XRF) methods as well. Our PAA results are consistent with XRF experimental data. The future of tracing the origin of illicit drugs with the PAA technique is promising.     

The continental component of a Pacific Marine aerosol: Identification by combined neutron activation analysis and scanning electron microscopy with X-ray analysis

The relative merits and sampling requirements of instrumental neutron activation analysis (INAA) and scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDS) analysis as applied to the continental component of marine aerosols are discussed. When correlated with air mass information, the quantitative INAA data on the concentrations of 15 major and minor elements in the continental dust fraction provides information on the geochemical type and location of the land source. Although the SEM/EDS technique provides only qualitative concentrations for 6 additional elements in the aerosol, the important feature of single particle analysis enables more nearly synoptic interpretation of aerosol composition and concentration. A combined INAA and SEM/EDS study of the aerosol samples is therefore preferred.     

化学计量学在锕系元素分析中的应用

锕系元素的化学性质相似,各元素的分离和分析都很困难,用传统的数据解析手段,难以实现各元素的同时、快速分析。化学计量学是一种高效、功能强大的数据解析方法,对于样品复杂,基体干扰严重以及多组分样品的分析具有独特优势。将化学计量学应用于锕系元素的分析中,利用数学分离代替化学分离,可直接对样品进行测定。化学计量学方法也可用来指导试样的科学采集,进行实验设计、仪器分析操作条件选择等。从吸收光谱、ICP–AES及放射性测量3个方面综述了化学计量学在锕系元素分析中的应用,阐明了化学计量学在锕系元素分析中的应用难点及发展前景。     

Trace element levels of aerosols at an urban area of Korea by instrumental neutron activation analysis

Instrumental neutron activation analysis was used to measure the concentrations of about 27 elements associated with airborne PM 10 samples that were collected from a roadside sampling station at a moderately polluted urban area of Taejon city, Korea. The magnitude of their concentrations was clearly distinguished and spanned over four orders. If compared in terms of enrichment factors, it was found that certain elements (e.g., As, Br, Cl, Sb, Se, and Zn) are enriched in PM 10 samples of the study site. The factor analysis indicated three factors with statistical significance, which may exert dominant controls on regulating the metal concentration levels in the study area.     

Multielement trace analysis of high purity aluminium by neutron activation

Instrumental neutron activation analysis was applied to multielement trace analysis of high purity aluminium samples. In order to reduce the production of²⁴Na from the matrix, samples were activated by thermal neutron flux of high cadmium ratio. Detection limits of various impurity elements were evaluated. So called “five nine” class standard aluminium samples were analyzed and concentrations of various impurity elements were determined. The analytical results obtained on zone refined aluminium samples showed that zone refining is effective against many elements, such as Na, Cr, Fe, Co, Cu, Ga, As, Br, Ba, La, Ce, Sm, Yb, Lu, Hf, W, Th and U, but not very effective against the element Sc.     

Application of multiple prompt gamma-ray analysis (MPGA) to geochemical and cosmochemical samples

A prompt gamma-ray analysis system using multiple detection method (MPGA system) was constructed at the neutron guide hall of the JRR-3M reactor of the Japan Atomic Energy Agency. We applied MPGA method to geochemical and cosmochemical samples to evaluate its analytical performance on signal to noise (S/N) ratio, sensitivity, and detection limit. The S/N ratio measured by MPGA system was larger than that by normal prompt gamma ray activation analysis (PGAA) at JRR-3M. For some elements, the S/N ratio was improved more than ten times. Several elements that are not detected by PGAA were detected by MPGA. At the present time, concentrations of major elements and trace elements with high neutron capture cross section in geochemical and cosmochemical samples were determined accurately by the MPGA system installed at JRR-3M. It is expected that it will determine a lot of trace elements after appropriate adjustments and modifications.     

Instrumental neutron activation analysis applied to the determination of the chemical composition of metallic materials with study of interferences

Summary Instrumental neutron activation analysis was applied to evaluate the chemical composition of metallic materials, namely iron, steel, silicon and ferrosilicon certified reference materials. As, Co, Cr, Mn, Mo, Ni, V and W concentrations were analyzed in the iron and steel samples whereas 21 elements were determined in silicon and ferrosilicon samples. Accuracy and precision results of about 10% were achieved for most elements, indicating that the technique is suitable for the analysis of metallic materials. Interferences of Cr and Mn in V; Fe and Co in Mn; Co in Fe and Cr in Ti were quantified and only the last one was critical to the analysis of the materials employed in this work.     

Sources of trace elements in total diet: A statistical approach

We have collected sixteen total diet samples from two socioeconomic groups in Turkey by duplicate portion techniques. Samples were homogenized with titanium-blade homogenizer, freeze dried and analyzed for their minor and trace elements mostly by neutron activation analysis. Bread and flour samples were also collected from the same regions and analyzed similarly by instrumental neutron activation analysis. We have determined concentrations of more than 25 elements in total diets, bread and flour, and fiber and phytate in total diets. We have determined daily dietary intakes of these population groups, probable source of elements through correlation coefficients, and enrichment factor calculations. This revised version was published online in July 2006 with corrections to the Cover Date.     

Purification of activated charcoal for use as sorbent in NAA of trace elements in volcanic exhalations

Activated charcoals were analyzed by neutron activation analysis to test their applicability as sorbents for some volatile trace elements in volcanic exhalations. A high temperature volatilization process was applied, which reduces the concentrations of some trace elements, in particular Br, Hg, Sb and Zn.     

Atmospheric trace metal characterization in industrial area of Lisbon, Portugal

Summary A set of 15 atmospheric aerosol samples was collected in an industrial area of Lisbon, Portugal and then analyzed by instrumental neutron activation analysis (INAA). Both fine and coarse aerosol samples were collected during November and December 2001 on polycarbonate filters with Gent samplers. The INAA methodology utilized both thermal and epithermal neutron irradiations. Compton suppressed and normal gamma-ray spectra were acquired simultaneously for each measurement and the elemental concentrations of 30 elements were determined. Enrichment factors, wind speed comparison and receptor modeling techniques were applied to obtain the different source contributions of the aerosols. Crustal, marine and anthropogenic sources were identified. The anthropogenic elements have origin mainly in the area close to the sampling site (<5 km), with the exception of Ca and V. A direct relationship was observed between the anthropogenic atmospheric aerosol concentrations and wind speed.     

Effects of fertilizer with different mineral composition on the absorption of Ca, Cu, K, Mg, Mn, Na and V, by two cultivars of pigeonpea (Cajanus cajan, Millsp)

Seventy-two leaf samples belonging to two cultivars of Cajanus cajanMillsp were analysed by instrumental neutron activation analysis (INAA). Thesamples came from plants treated with two doses of fertilizer containing eachof the following elements: B, Co, Cu, Fe, Mn, Mo, V and Zn, which were applied,individually, to the soil. The leaf samples were yielded at two differenttimes. The purpose of this paper is to elucidate the influence of each fertilizer,the dose and leaf harvest time, on the concentrations of Ca, Cu, K, Mg, Mn,Na and V, and the behavior of both cultivars in relation to the concentrationsof these elements.     

Ocean-sediment analysis by neutron activation

Neutron activation analysis (NAA) techniques have been developed and applied to the analysis of marine sediments. More than 150 core sites have been sampled in the northwestern Gulf of Mexico. More than 500 surface and subsurface sediment samples have been analyzed for Ba, Cr, Fe, and various other elements of interest. Typical concentrations at various locations are given. An extensive half-life study was performed to verify that gamma lines, used for quantitation exhibited the decay parameters expected to the parent radionuclide. Suggested gamma lines are presented for a few elements of particular interest to ocean-sediment analysis.     

测定土壤中重金属元素时前处理方法的改进

建立了一种微波消解前处理技术的半消解法消解样品,采用原子吸收光谱法和原子荧光光谱法同时测定土壤中主要重金属元素铜、锌、镉、砷、汞的方法,检测土壤标准物质GSS-3、GSS-5、GSS-20,结果显示测定均值在标准差允许范围内,相对标准偏差小于8.5%(n=4),是土壤重金属元素快速检测的可选方法。     

Neutron activation analysis of ivory of African elephants

Instrumental neutron activation analysis was applied to 80 samples from various African countries and 81 samples from the Kruger National Park in the Republic of South Africa. Twelve elements such as Br, Ca, Cl, Co, Cs, Fe, Mg, Mn, Na, Sc, Sr, and Zn, were determined in all samples. The factor scores of each sample were calculated from those elemental concentrations for the first and second factors to clarify the differences of samples from various African countries with those from Kruger Park. The results were compared with those by stable isotope analysis (¹³C and¹⁵N).