Application Of Neutron Activation Analysis Research Articles

The determination of wear elements in lubricating oils by neutron activation analysis

Used lubricating oil analysis programs are currently employed by both the military and industry in an attempt to minimize some of the costs associated with equipment failure. The periodic determination of water elements in the lubricant of an oil-wetted system can provide very useful information on the condition or health of the system and an early indication of impending failure. In the present study, the application of Neutron Activation Analysis (NAA) to used oil analysis was investigated. The method developed allowed for the determination of fifteen elements (Ag, Al, Cl, Cr, Cu, Fe, In, Mg, Mn, Mo, Na, Ni, Sn, Ti and Zn) associated with engine wear or deterioration. Results obtained for the analysis of used naval diesel oils exhibited good agreement with results obtained by Atomic Absorption Spectrophotometry (AAS) methods. A drawback of the NAA procedure is that the determination of Fe, a major wear element in most systems, involves an analysis time of approximately one week.

External and internal dosimetry of persons exposed to thorium and application of neutron activation analysis to study its biokinetic behaviour

This article summarizes external and internal dosimetry studies in different population groups exposed to varying amounts of thorium. A dosimetry survey of the general population of monazite areas has shown that the average external dose equivalent in some geographical areas is as high as 10 mSv per year. Internal exposures are investigated in the occupational persons using the method of direct body gamma spectrometry and the analysis of exhaled breath, urine, blood serum and blood cells. Body gamma spectrometry and breath analysis do not have sufficient sensitivity to detect minor exposures. The neutron activation method, developed to analyse biological samples, is used to make precise measurements of thorium in the body fluids. The urine and serum concentration results so obtained are used to derive important conclusions about the excretion kinetics of thorium. Approximately 15% of the thorium content of the blood serum appears to be excreted daily through urine.

Advances in Neutron Activation Analysis

Abstract A. Aims of the Review The 50th anniversary of the description of neutron activation analysis (NAA) by Hevesy and Levi1 was celebrated at the Seventh Modern Trends in Activation Analysis Conference (MTAA-7) held in Copenhagen, Denmark, in June 1986. NAA is now considered to be a mature field. The principles are well understood, and no dramatic improvements in either instrumentation or methodology that would revolutionize the method are expected. This is in contrast to other analytical techniques where significant advances and changes in instrumentation and scope of applications are seen within a relatively short time. However, the field of NAA remains vigorous as researchers continue to develop innovative applications of NAA using existing facilities, link NAA with the developing technologies in separation science to form a unique and powerful new group of “hyphenated techniques”, refine sample handling and data processing procedures, and continually strive to improve the quality of the data generated by activation analysis procedures. An excellent brief review of developments that were presented at MTAA-7 has been provided by Heydorn.2

Application of neutron activation analysis in chemical yield determination for89Sr and90Sr separation of environmental samples

For89Sr and90Sr determination in grass samples neutron activation analysis was employed as an advantageous method for yield measurements during the separation process. From the activity ratio found conclusions on the source of radioactivity are possible taking into consideration the dependence on reactor operating time.

Application of neutron activation analysis for investigating the genesis of tertiary magmatities from the South of the GDR

With the help of NAA a number of trace elements were determined in ultrabasic rocks, xenolithes of alkali basalts, basalts, phonolites and pyroxene inclusions in phonolites from the South of the GDR. The formation of the investigated magmatites were explained by metasomatism, partial melting and fractionated crystallization in the earth mantle.

New composite ion exchanger—hydrated antimony pentoxide in phenolsulphonic matrix—and its application in neutron activation analysis : A Bilewicz, B. Bartós, H. Polkowska-Motrenko and J. Narbutt, Department of Radiochemistry and Department of Analytical Chemistry Institute of Nuclear Chemistry and Technology, Warsaw, Poland

New composite ion exchanger—hydrated antimony pentoxide in phenolsulphonic matrix—and its application in neutron activation analysis : A Bilewicz, B. Bartós, H. Polkowska-Motrenko and J. Narbutt, Department of Radiochemistry and Department of Analytical Chemistry Institute of Nuclear Chemistry and Technology, Warsaw, Poland

Applications of neutron activation analysis to the study of age-related neurological diseases

Although the etiology and pathogenesis of Alzheimer's disease, Pick's disease, and amyotrophic lateral sclerosis are still unknown, it has been suggested that perturbations in element metabolism may play a role. Even if not causative factors, these imbalances may prove to be markers that could aid in diagnosis. We have employed a sequential neutron activation analysis (NAA) procedure to determine elemental concentrations in brain, hair, fingernails, blood, and cerebrospinal fluid (CSF) of these patients and age-matched controls. Samples are first irradiated with accelerator-produced 14-MeV neutrons for determination of nitrogen and phosphorus, then with reactor thermal neutrons for the instrumental determination of 16-18 minor and trace elements, and, finally, reactor-irradiated again, followed by a rapid radiochemical separation procedure (RNAA) to determine four additional elements. Major advantages of NAA are: (1) its simultaneous multielement capability; (2) the relative freedom from reagent and laboratory contamination; (3) the absence of major matrix effects; and (4) an adequate sensitivity for most elements of interest. Ranges of concentrations by INAA and RNAA in selected control tissues and interelement correlations in control brain are presented to illustrate results obtained by the procedure. Longitudinal studies of tissues from Alzheimer's disease (AD) and amyotrophic lateral sclerosis (ALS) patients are still in progress.

Application of neutron activation analysis in the field of silicon technology for the modern electronic industry

The specific application of neutron activation analysis in the research on the preparation of silicon integrated circuits is discussed. The high flux irradiation facility for large silicon wafers (up to 15 cm diameter) was used, the analytical procedure, and some typical results will be described.

Application of NAA in determining the inorganic contents of the fruit fly (Ceratitis capitata Wied.) and its artificial food

The neutron activation analysis (NAA) was applied to the multielement analysis of the mediterranean fruit fly, Ceratitis capitata Wied., taken from a stock produced at the Tropical Scientific Research Institut (IICT) in Lisbon, and to its artificial food. Dry samples were irradiated in the OSIRIS reactor, within a work performed at the Laboratoire d'Analyse par Activation Pierre Sue (CEA/CEN-Saclay). The contents of Ca, K, Mg, Cl, Na, Fe, Zn, Al, Mn, Ba, Rb, Br, Co and Cs for the cases of Ceratitis capitata Wied. eggs, larvae, pupae, males and females and of its artificial food are reported.

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).

Regression Code for Neutron Activation Analysis

A micro computer code is introduced. It has been developed essentially for neutron activation analysis application. The code is quite general and modular that it may be found useful in various routine analysis of data by regression analysis technique.

Application of neutron activation analysis in clinical chemistry.

Acta Pharmacologica et ToxicologicaVolume 59, Issue s7 p. 585-588 APPLICATION OF NEUTRON ACTIVATION ANALYSIS IN CLINICAL CHEMISTRY. R. Cornelis, R. Cornelis Laboratory for Analytical Chemistry, Rijksuniversiteit Gent, Proeftuinstraat 86, B-9000 Gent, Belgium. R. Cornelis is a senior research associate of the National Fund for Scientific Research.Search for more papers by this author R. Cornelis, R. Cornelis Laboratory for Analytical Chemistry, Rijksuniversiteit Gent, Proeftuinstraat 86, B-9000 Gent, Belgium. R. Cornelis is a senior research associate of the National Fund for Scientific Research.Search for more papers by this author First published: December 1986 https://doi.org/10.1111/j.1600-0773.1986.tb02831.x AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Volume59, Issues7December 1986Pages 585-588 RelatedInformation

Application of neutron activation analysis for determination of mercury, iron, europium, lanthanum and potassium in asbestos

Various chrysolite-asbestos from Canada and Russia, asbestos plate and, dry as well as wet manufactured asbestos, were analyzed for Hg, Fe, Eu, La and K by the neutron activation method. Following concentration values were found: Hg 0.01–0.46 ppm, Fe 4818–32738 ppm, Eu 0.02–0.125 ppm, La 0.061–0.874 ppm, K 14.829–358.5 ppm. Statistically significant differences /t=0.05/ in Hg, Fe, Eu, La and K contents were found in the different asbestos samples. The concentration of Hg, Fe, Eu in Italian asbestos were considerably higher than in Canadian chrysolite. High Concentration of La, K were found in Austrian asbestos plate.

Application of neutron activation analysis to forensic chemistry.

Neutron activation analysis is one of the best multielement analytical techniques and has been applied to the problem of forensic sciene. There are mainly two areas of application in forensic chemistry. The first is a multi-element analysis for the purpose of identifying a sample with its soure or origin by comparison of trace element patterns, for example, to determine the origin of opiums and cannabis. Trace characterization of a synthetic drug such as methamphetamine hydorchloride was achieved by this method and synthetic method of the drug was also assumed. Hair samples were analyzed for the purpose of monitering the environmental polution. In certain case, these data would be useful in the crime investigation. The second is its straightforward use as a method of trace element concentration determination, for example, in toxicology to detect arsenic or mercury in biological samples. It permitted interference-free analyses of trace amounts of halogens, germanium, and serenium. In the case work studies, detective analysis was another application of neutron activation analysis, because it could be determined both expected and unexpected elements in the physical evidence.

Radionuclides in Environmental Research and Protection

Radioisotopes of both natural and artificial origin are widely used in environmental research and protection to tackle problems in which high specificity and sensitivity are required. The paper exemplifies the capabilities guided by some recent investigations in various fields of application: dating of river and marine sediments, determination of dry deposition rates for airborne particulates, studies of the uptake of organic compounds by plants and of the internal distribution processes in plants, investigation of transport phenomena in soil, groundwater or surface waters, development of trace analytical procedures, application of neutron activation analysis, detection of trace gases by means of ionization detectors, and the exploration of mud fields in tidal rivers using a radiometric density gauge.

Application of neutron activation analysis for trace element determinations in biological materials

Over the past three decades, more and more interest has been focused on trace eleemnts in biological materials. This increasing interest has gone hand in hand with the continuous improvement of analytical techniques. Neutron activation analysis has proven to be a most suitable method for the quantitative determination of a wide variety of trace (0.01–100 μg g −1) and ultratrace (<0.01 μg g −1) elements in biological materials. This technique has even played a preponderant role in this field.

Application of neutron activation analysis and spectrophotometry for the determination of copper level in sera and cerebrospinal fluids of schizophrenic patients

Neutron activation analysis and spectrophotometry were used for the determination of copper content in sera and cerebrospinal fluids of schizophrenic patients against control persons. From the analytical data conclusions can be drawn for the psychotic state of the patients.

Compton suppression gamma-counting: The effect of count rate

Past research has shown that anti-coincidence shielded Ge(Li) spectrometers enhanced the signal-to-background ratios for gamma-photopeaks, which are situated on high Compton backgrounds. Ordinarily, an anti- or non-coincidence spectrum (A) and a coincidence spectrum (C) are collected simultaneously with these systems. To be useful in neutron activation analysis (NAA), the fractions of the photopeak counts routed to the two spectra must be constant from sample to sample to variations must be corrected quantitatively. Most Compton suppression counting has been done at low count rate, but in NAA applications, count rates may be much higher. To operate over the wider dynamic range, the effect of count rate on the ratio of the photopeak counts in the two spectra (A/C) was studied. It was found that as the count rate increases, A/C decreases for gammas not coincident with other gammas from the same decay. For gammas coincident with other gammas, A/C increases to a maximum and then decreases. These results suggest that calibration curves are required to correct photopeak areas so quantitative data can be obtained at higher count rates.

Chapter 7 Application of neutron activation analysis to silicon characterization

Chapter 7 Application of neutron activation analysis to silicon characterization

Quality assurance in biomedical neutron activation analysis: Report of an Advisory Group of the International Atomic Energy Agency, Vienna, Austria

Evidence from various sources leads to the conclusion that all current methods for the determination of trace elements in biological materials may, as currently practised, be subject to significant error, even as large as several orders of magnitude. This report, prepared by an Advisory Group convened by the International Atomic Energy Agency, examines possible sources of error arising in the application of neutron activation analysis to biomedical materials, and attempts, in the light of current knowledge, to recommend practical and effective means to avoid them. The topics discussed include sampling and sample preparation, standards, the activation of samples and standards, chemical separations, γ-ray spectrometry, and general methods of internal and external quality assurance.