Nuclear Analytical Techniques Research Articles

Compositional analysis and depth profiling of thin film CrO2 by heavy ion ERDA and standard RBS: a comparison

Chromium dioxide (CrO 2 ) thin film has generated considerable interest in applied research due to the wide variety of its technological applications. It has been extensively investigated in recent years, attracting the attention of researchers working on spintronic heterostructures and in the magnetic recording industry. However, its synthesis is usually a difficult task due to its metastable nature and various synthesis techniques are being investigated. In this work a polycrystalline thin film of CrO 2 was prepared by electron beam vaporization of Cr 2 O 3 onto a Si substrate. The polycrystalline structure was confirmed through XRD analysis. The stoichiometry and elemental depth distribution of the deposited film were measured by ion beam nuclear analytical techniques heavy ion elastic recoil detection analysis (ERDA) and Rutherford backscattering spectrometry (RBS), which both have relative advantage over non-nuclear spectrometries in that they can readily provide quantitative information about the concentration and distribution of different atomic species in a layer. Moreover, the analysis carried out highlights the importance of complementary usage of the two techniques to obtain a more complete description of elemental content and depth distribution in thin films. Heavy ion elastic recoil detection analysis (ERDA) and Rutherford backscattering spectrometry (RBS) both have relative advantage over non-nuclear spectrometries in that they can readily provide quantitative information about the concentration and distribution of different atomic species in a layer. ► Thin films of CrO 2 have been grown by e-beam evaporation of Cr 2 O 3 target in vacuum. ► The composition was determined by heavy ion—ERDA and RBS. ► HI-ERDA and RBS provided information on the light and heavy elements, respectively.

Application of nuclear analytical techniques for assessment of coastal impact

Marine sediments contain a record of past events and proved to be an interesting indicator matrix for this study. Instrumental neutron activation analysis and energy dispersive X-ray fluorescence techniques offer adequate sensitivity for analysis of trace elements. Grain size analysis of sediment samples before and after tsunami showed a shift in textural characteristics of the sediment which is not observed during regular monsoon and seasonal changes. Some general characteristics of sediments revealed sand content ranges between 39 and 65% and silt from 33 to 53%. Clay content was found low averaging 5.4% and varied from 2 to 13% (by weight). The concentration of Cu, Ni, Fe, Pb, Zn, Mn, Rb, Sr, Ti, K, and Ca varies from 12 to 53, 19–46, 21,952–36,785, 21–39, 39–67, 335–856, 47–61, 223–400, 4,991–8,054, 11,000–15,791, and 5,878–11,214 mg kg−1, respectively. The positive correlation was observed for Cu, Ni, Ti, K, and Rb with respect to Fe. The negative correlation was observed for Ca, Sr, Zn, and Pb with respect to Fe, indicating the different source for these metals in the marine sediment. Decrease of the particle-reactive element in the tsunami impacted sediment indicates removal of clay component in the sediment, which is supported by the presence of low Th/U ratio.

Characterization of geomaterials from NE Portugal using k 0-based instrumental neutron activation analysis (k 0-INAA) and gamma spectrometry methods

The main objective of this study is the elemental characterization of geomaterial samples (“soils” and Ranas), collected between 2007 and 2008, in the Morais Massif, (NE Mainland of Portugal) by using two complementary techniques: instrumental neutron activation analysis (INAA) and high resolution gamma spectrometry. Samples granulometric fractions lower than 63 μm were analyzed by gamma spectrometry, for artificial and natural radionuclides using HPGe detectors and by INAA, for chemical elements at the Portuguese research reactor, RPI. Statistical analysis, such as clusters analysis and Pearson correlations were applied to the obtained results. The enrichment factors were also calculated as an estimator of anthropogenic inputs in relation to the average crustal abundance. Group differentiation of Ranas and “soils” is clearly shown from cluster analysis. The strong correlation factors obtained between some chemical elements corroborates the origins and the geology/mineralogy of the area studied. The combined application of both nuclear analytical techniques has shown their importance in providing useful information for the future site and repository performance and safety assessment studies.

Analytical Methods INAA and PIXE Applied to Characterization of Airborne Particulate Matter in Bandung, Indonesia

Urbanization and industrial growth have deteriorated air quality and are major cause to air pollution. Air pollution through fine and ultra-fine particles is a serious threat to human health. The source of air pollution must be known quantitatively by elemental characterization, in order to design the appropriate air quality management. The suitable methods for analysis the airborne particulate matter such as nuclear analytical techniques are hardly needed to solve the air pollution problem. The objectives of this study are to apply the nuclear analytical techniques to airborne particulate samples collected in Bandung, to assess the accuracy and to ensure the reliable of analytical results through the comparison of instrumental neutron activation analysis (INAA) and particles induced X-ray emission (PIXE). Particle samples in the PM 2.5 and PM 2.5-10 ranges have been collected in Bandung twice a week for 24 hours using a Gent stacked filter unit. The result showed that generally there was a systematic difference between INAA and PIXE results, which the values obtained by PIXE were lower than values determined by INAA. INAA is generally more sensitive and reliable than PIXE for Na, Al, Cl, V, Mn, Fe, Br and I, therefore INAA data are preffered, while PIXE usually gives better precision than INAA for Mg, K, Ca, Ti and Zn. Nevertheless, both techniques provide reliable results and complement to each other. INAA is still a prospective method, while PIXE with the special capabilities is a promising tool that could contribute and complement the lack of NAA in determination of lead, sulphur and silicon. The combination of INAA and PIXE can advantageously be used in air pollution studies to extend the number of important elements measured as key elements in source apportionment. Received: 20 November 2010; Revised: 09 August 2011; Accepted: 15 August 2011

Nuclear analytical techniques for nanotoxicology studies

Abstract With the rapid development of nanotechnology and its applications, a wide variety of nanomaterials are now used in commodities, pharmaceutics, cosmetics, biomedical products, and industries. The potential interactions of nanomaterials with living systems and the environment have attracted increasing attention from the public, as well as from manufacturers of nanomaterial-based products, academic researchers and policymakers. It is important to consider the environmental, health and safety aspects at an early stage of nanomaterial development and application in order to more effectively identify and manage potential human and environmental health impacts from nanomaterial exposure. This will require research in a range of areas, including detection and characterization, environmental fate and transport, ecotoxicolgy and toxicology. Nuclear analytical techniques (NATs) can play an important role in such studies due to their intrinsic merits such as high sensitivity, good accuracy, high space resolution, ability to distinguish the endogenous or exogenous sources of materials, and ability of in situ and in vivo analysis. In this paper, the applications of NATs in nanotoxicological and nanoecotoxicological studies are outlined, and some recent results obtained in our laboratory are reported.

IAEA Activities on Cultural Heritage, Archaeology and other Characterization Applications

Trace element determination is crucial for identifying the provenance and authenticity of intact ancient objects such as cultural and art artefacts, archaeological findings and forensic materials, geological objects, etc. A non-destructive technique suitable for analysis of trace elements in bulk-samples is highly needed. The IAEA initiated a series of coordinated research projects (CRP) to support Member States on their R&D programs. Large Sample Neutron Activation Analysis (LSNAA) is a very attractive non-destructive technique that can be applied without a need for sub-sampling and homogenization. LSNAA can be operated in ‘on-line’ mode which is based on the use of isotopic neutron sources, neutron generators and prompt gamma analysis. An on-going CRP focuses primarily on the application of LSNAA in the area of archaeological and geological programmes. However, further utilization of LSNAA in other subjects of industry and research is promising. Large scale campaigns of archaeological excavations are undertaken in the Mediterranean region. The IAEA is supporting Technical Cooperation projects in the Middle East in view of studying authenticity and origin of objects of art and archaeology, as well as to characterize new elaborated materials or environmental samples, making use of Ion Beam Accelerators (IBA) as nuclear analytical tool and other nuclear analytical techniques. The application of nuclear analytical tools in archaeology is of special concern as many common ancient civilizations are shared by the Mediterranean state. The main IBA techniques to be used are: PIXE, PIGE and RBS, as well as XRF. To take advantage of these nuclear techniques, many researchers from the participating countries have initiated several studies and exchange of experience, knowledge, results and expertise is on-going.

Study on homogeneity of multielements for a stream sediment matrix material with nuclear analytical techniques

Taking advantages of nuclear analytical techniques (NATs) with non-destruction, multielement capability, small and estimable uncertainties over a wide range of sample sizes, the sampling behavior of multielements for a home-made natural matrix material was studied with sample sizes ranging from several hundred mg down to tenths ng, namely nine orders of magnitude, by a combination of three NATs, neutron activation analysis (NAA), proton induced X-ray emission (PIXE) and synchrotron radiation X-ray flurescence (SR-XRF), in an effort to explore a procedure for the development of certified reference materials (CRMs) suitable for quality control of microanalysis. For accurately weighable sample sizes (>1 mg), sampling uncertainties for 13 elements were found to be less than 1% by INAA. For sample sizes unable to be accurately weighed (<1 mg), PIXE and SR-XRF were used, respectively. Sampling uncertainties were found to be less than 1% at sample sizes of tenth mg level for seven elements, and less than 10% on ng levels for three elements. Considering these three elements have satisfied homogeneity (sampling uncertainty less than 10%) at ng sample size level, any one of them can be served as a “relative balance” in sampling behavior characterization of multielements on sample size levels larger than ng (e.g., μg level). On this basis, sampling uncertainties for nine elements were found to be less than 10% on μg sample size level by INAA. The results indicate that the matrix is eligible as a candidate of CRMs suitable for quality control of solid sampling microanalysis.

Is there a future for biomonitoring of elemental air pollution? A review focused on a larger-scaled health-related (epidemiological) context.

The present paper focuses on biomonitoring of elemental atmospheric pollution, which is reviewed in terms of larger-scaled biomonitoring surveys in an epidemiological context. Based on the literature information, today’s availability of solar-powered small air filter samplers and fibrous ion exchange materials is regarded as adequate or an even better alternative for biomonitor transplant materials used in small-scaled set-ups, but biomonitors remain valuable in larger-scaled set-ups and in unforeseen releases and accidental situations. In the latter case, in-situ biomonitoring is seen as the only option for a retrospective study: biomoniors are there before one even knows that they are needed. For biomonitoring, nuclear analytical techniques are discussed as key techniques, especially because of the necessary multi-element assessments in both source recognition and single-element interpretation. To live up to the demands in an epidemiological context, larger-scaled in-situ biomonitoring asks for large numbers of samples, and consequently, for large total sample masses, this all to ensure representation of both local situations and survey area characteristics. Possibly, this point should direct studies into new “easy-to-sample” biomonitor organisms, of which high masses and numbers may be obtained in field work, rather than continue with biomonitors such as lichens. This also means that both sample handling and processing are of key importance in these studies. To avoid problems in comparability of analytical general procedures in milling, homogenization and digestion of samples of large masses, the paper proposes to involve only few but high-quality laboratories in the total element assessment routines. In this respect, facilities that can handle large sample masses in the assessment of element concentrations are to be preferred. This all highlights the involvement of large-sample-volume nuclear facilities, which, however, should be upgraded and automated in their operation to ensure the necessary sample throughput in larger-scaled biomonitoring.

INAA laboratory results evaluation of inter-laboratory analysis test

Participation in inter-comparison programs is an important process to enhance the accuracy and precision of the analytical techniques. The Instrumental Neutron Activation Analysis laboratory (INAA) at Egypt Second Research Reactor (ETRR-2), ETRR-2 INAA Laboratory, was participated in three inter-comparison tests organized by AFRA Research Reactor Project for Socio-economic development. AFRAIV-12 Inter-laboratory Analysis Test 2007 is the third inter-laboratory analysis test within that project. The laboratories were asked to analyze for 43 essential and toxic elements using nuclear and related analytical techniques, with neutron activation analysis as the common technique. Five materials were distributed to the participants representing foodstuff, medicinal plants and aquatic biomonitors according to the focus of the AFRA IV-12 2006-2010 project. In this paper the ETRR-2 INAA Laboratory results is evaluated.

Determination of Element Levels in Selected Wild Mushroom Species in Turkey Using Non-Destructive Analytical Techniques

The elemental concentration of K, Fe, Cu, Mn, Zn, Pb, Cd, Ni, Sn, Br, Sr, Ti, Rb, As, Th, an U in eleven wild growing mushroom species collected from various regions of Turkey were determined by using non-destructive nuclear analytical techniques like tube-excited energy dispersive X-ray fluorescence and gamma ray spectroscopic measurements. The highest element concentrations for K, Fe, Cu, Mn, Zn, Pb, Cd, Ni, Sn, Br, Sr, Ti, Rb, As, Th, and U were 50977 ± 3982, 2971 ± 749, 99.1 ± 5.5, 71.3 ± 49.1, 266 ± 109, 5.6 ± 0.1, 3.08 ± 0.91, 3.6 ± 0.7, 1.6 ± 0.1, 27.2 ± 19.7, 19.9 ± 2.1, 602. ± 166, 72.4 ± 24.5, 3.7 ± 0.7, 1.8 ± 0.9 and 0.42 ± 0.13 mg/kg dry mass, respectively.

Ultra-trace Measurements of 210Pb in natural occurring radioactive materials by ICP-MS

Collision cell inductively coupled plasma mass spectrometry (CC-ICP-MS) was investigated as a possible alternative to nuclear analytical techniques for the determination of 210Pb. The formation of isobaric and polyatomic interferences was studied. Following the acid digestion, extraction chromatography was tested to assess their usefulness in reducing its interferences. A 210Pb pre-concentration of >300-fold and recoveries of 63–73% were obtained using a combined extraction chromatography and pre-concentration by evaporation protocol. Improvement in sensitivity of 210Pb was found by optimization of the collision cell parameters using krypton as a collision gas. The detection limit was improved by a factor of 300 for 210Pb. A detection limit of 0.214 ppt (0.698 Bq/mL) was obtained. The method was applied to determine 210Pb in samples of naturally occurring radioactive materials (NORM).

A comparison of two nuclear analytical techniques for determination of 210Pb-specific activity in solid environmental samples

Two nuclear analytical techniques for determination of 210Pb-specific activity in solid environmental samples have been validated and compared. The first technique depends on determination of 210Pb via its alpha emitting daughter 210Po using alpha-particle spectrometry, while the second technique is based on direct determination of 210Pb by measuring its activity at the 46-keV gamma line by low-energy gamma-ray spectrometry. Detection limits, repeatability, reproducibility, and surrogate recovery were the main validation parameters. Measurement uncertainties were estimated and compared for both techniques. Results of this study have shown that the expected activity of 210Pb in the environmental samples and the required measurement uncertainty are the main factors influencing a selection of the appropriate method for the application.

Comments on “Quality assurance of nuclear analytical techniques based on Bayesian characteristic limits”

A paper by R. Michel in this journal (J. Radioanal. Nucl. Chem., 245 (2000) 137) describes, among other things, a numerical example: the calculation of characteristic limits in an analysis of 129I via radiochemical NAA. A key problem in Bayesian characteristic limits is a proper formulation of the expression for the uncertainty associated with the measurand if its true value is equal to zero, ũ(0). We show that MICHEL’s expression for ũ 2(0) is not correct and propose a new one. Some numerical errors found in the paper are also indicated.

Neutron activation analysis and natural radioactivity measurements of lignite and ashes from Megalopolis basin, Greece

Elemental concentrations and specific activity values of natural radionuclides were measured in lignite, bottom ash and fly ash samples collected from the Megalopolis power plant A in southern Greece, using nuclear analytical techniques. The results show that the elements As, Br, Mo, Sb, Se, and U were enriched in the lignite samples, the elements Mo, Se and U in bottom ash, while fly ash samples were enriched in As, Mo, Sb, Se and U. Specific activity measurements also show that 238U (226Ra) activity values in lignite and both ash samples were high relative to the corresponding data for coal and earth crust given in the literature. As a high quantity of fly ash is produced during the operation of the lignite power plant A, this power plant should be considered as a major source of air particulate pollution and radiation to the population living in the vicinity of lignite burning power plant.

환경 시료 중 신뢰도 검증을 위한 방사능 분석

1998년부터 2006년까지 국내 방사능 교차분석에 참여하여 제주지역의 환경방사능 감시를 위한 방사능 분석 기술의 능력 검증과 신뢰도를 확보하기 위하여 수행되었다. 전베타 방사능 분석 시료는 공기부유진 필터와 물이었고, 감마 분석은 토양과 물 시료 중 자연 및 인공 방사성 핵종들이었다. 전베타 방사능 분석 값은 1998년과 1999년 물 시료를 제외하고는 모두 신뢰도 범위내의 값을 가졌고, 감마 핵종은 토양 시료 중의 <TEX>$^{40}K$</TEX>와 <TEX>$137^{CS}$</TEX> 그리고 물 시료 중 몇 개의 핵종을 제외하고는 대부분 매우 우수한 평가를 받았다. 따라서 방사선 이상 사고시 원자력 안전을 위한 제주지역의 환경방사능 감시를 위한 신뢰도를 확보하여 자체적으로 환경방사능을 분석할 수 있는 능력을 함양하였다. The objective of this research was to assess the reliability of data and to improve nuclear analytical techniques concerning the Domestic Radioactivity Intercomparison program for environmental radioactivity monitoring of Jeju from 1998 to 2006. Gross beta for filter papers and water samples was determined, and gamma nuclides for natural and artificial nuclides in soil and water samples were analyzed. The gross beta activity of all samples except for the water samples of 1998 and 1999 showed a good agreement within the confidence intervals. In gamma nuclides, <TEX>$^{40}K$</TEX> and <TEX>$^{137}Cs$</TEX> of soil samples and most nuclides in the water samples, with the exception of several nuclides, were evaluated to be reliable. Based on these results, it is considered that a reliable method for the analysis and monitoring of environmental radioactivity were established, which may play an important role in case of emergency radiation accident.

ARCHAEOMETRY AT THE ARGENTINE NATIONAL ATOMIC ENERGY COMMISSION: CHARACTERIZATION OF ARGENTINE NORTHWESTERN POTTERY

This paper provides a description of the Nuclear Analytical Techniques Group of the Argentine National Atomic Energy Commission, at the Ezeiza Atomic Center. In 1963, this laboratory performed the first application of neutron activation analysis in Argentina and currently employs the technique to analyse a variety of matrices, including archaeological ceramics. The group has collaborated on different research projects since the 1980s, when the first characterization of archaeological ceramics was performed. A brief history of the laboratory and the results from the analysis of potsherds and raw materials from northwestern Argentina are presented below.

Study of loss and recuperation of inorganic elements of osteoporotic rat bone with nuclear analytical techniques

Neutron activation analysis (NAA) and synchrotron radiation X-ray fluorescence analysis (SRXRF) were used to study the loss and recuperation of inorganic elements of osteoporotic rat bone and the effects of Zhugu Capsule. The results of the animal experiments showed that there was greater loss of multiple elements in cancellous bone than in cortical bone that was difficult to be improved. Yet in the mid-shaft femur, which is mainly consisted of cortical bone, the contents of multiple elements were notably recuperated. Zhugu Capsule could increase the content of not only of Ca, but also Zn and Sr. Further, it could also improve the distribution of these elements in femur.

Advanced nuclear analytical techniques for metalloproteomics

Metalloproteomics is an emerging scientific field. It is focused to investigate the distributions and compositions of all metalloproteins in a proteome, their structural and functional characterization and their structural metal-binding moieties. Various nuclear analytical techniques, such as neutron activation analysis, X-ray fluorescence, isotope tracer, Mossbauer spectrometry, X-ray absorption spectrometry and neutron scattering and diffraction, are powerful tools to study a number of the basic issues in metalloproteomics. In this paper, the applications of the advanced nuclear techniques in this field are selectively outlined, along with their advantages and limitations.

Metallomics—an interdisciplinary and evolving field

In an editorial earlier this year (JAAS, 22, 111, 2007), we opined that metallomics, the study of metals in biological systems, would be an increasingly important topic in elemental analysis in general and for this journal in particular . This issue of the journal, co-edited by the two of us, is a second special issue covering the subject of Metallomics (the first issue was JAAS, 19/1, 2004). The present issue is comprised of technique, application, and perspective papers that address this emerging field of study and show how atomic spectrometry is contributing to the understanding of biological systems. The subjects covered range from metal binding in plants through investigations of metal and metalloids in samples of biological fluids to the study of food supplements and drug interactions in cells. The issue includes two Critical Reviews. Yuxi Gao and colleagues discuss advanced nuclear analytical techniques for the emerging field of metalloproteomics. While Laura Liermann and her colleagues consider how micro-organisms extract metals from minerals in the environment for utilization in metabolic processes. The content of some of these papers stretches the traditional boundaries and scope of this journal, as echoed by the reviewers of some of the papers. This discussion aboutmore » scope requires perhaps further debate. However, it is our view that while the Journal must remain true to its core aims, it must also strive to accommodate and motivate a wider authorship and readership. Metallomics is a field that transcends biology and microbiology, biochemistry, clinical chemistry, environmental chemistry, geochemistry, and yes, atomic spectroscopy. If JAAS aspires to be a leading force in metallomics, the Journal must expand its horizons beyond traditional analytical spectroscopy per se. Accordingly, in this special issue you will find papers that have a heavy clinical emphasis, which speak to complementary (non-atomic) spectroscopic techniques, and that provide perspectives that only touch on the use of atomic spectroscopy. The field of metallomics is still in the process of being defined and we hope to inform that definition by including the widest body of technical literature on the subject. We hope that you will find these contributions to be informative, inspiring, and enlightening and consider submitting your own research in this area to JAAS.« less

Investigation of trace element atmospheric pollution by nuclear analytical techniques at a global scale: Harmonised approaches supported by the IAEA

In the framework of the IAEA programmes, Member States involved in air pollution studies using nuclear analytical techniques have harmonised their methodologies. Participants characterising chemical composition of size fractionated airborne particulate matter based their methodology on a common type of air sampler, centralised data collection and evaluation, and the same kind of data processing. Institutions involved in biomonitoring air pollution identified appropriate organisms to be applied at a regional scale, and harmonised procedures for sample preparation and analysis, as well as data processing and presentation. Both metrology approaches have been validated and disseminated in many Member States.