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Our lab has been developing a deuterium-deuterium (DD) neutron generator-based neutron activation analysis (NAA) system to quantify metals and elements in the human body in vivo. The system has been used to quantify metals such as manganese, aluminum, sodium in bones of a living human. The technology provides a useful way to assess metal exposure and to estimate elemental deposition, storage and biokinetics. It has great potential to be applied in the occupational and environmental health fields to study the association of metal exposure and various health outcomes, as well as in the nutrition field to study the intake of essential elements and human health. However, the relatively low sensitivity of the system has greatly limited its applications. Neutron moderation plays an important role in designing an IVNAA facility, as it affects thermal neutron flux in irradiation cave and radiation exposure to the human subject. This study aims to develop a novel thermal neutron enhancement method to improve the sensitivity of the in vivo neutron activation analysis (IVNAA) system for elemental measurement but still maintain radiation dose. Utilizing a compact DD neutron source, we propose a new and practical moderator design that combines high density polyethylene with heavy water to enhance thermal neutrons by reducing thermal neutron absorption. All material dimensions are calculated by PHITS, a general-purpose Monte Carlo simulation program. The improvement of the new design predicted by the Monte Carlo simulation for the quantification of one of the elements, manganese was verified by experimental irradiation of manganese-doped bone equivalent phantoms. For the same radiation dose, a 67.9% thermal neutron flux enhancement is reached. With only 4.2% increase of radiation dose, the simulated thermal neutron flux and activation can be further increased by 84.2%. A 100% thermal neutron enhancement ratio is also achievable with a 20% dose increase. The experimental results clearly show higher manganese activation gamma ray counts for each specific phantom, with a significantly reduced minimum detection limit. Additionally, the photon dose was suppressed. The thermal neutron enhancement method can increase the number of useful neutrons significantly but maintain the radiation dose. This greatly decreased the detection limit of the system for elemental quantification at an acceptable dose, which will broadly expand the application of the technology in research and clinical use. The method can also be applied to other neutron medical applications, including neutron imaging and radiotherapy.

Instrumental neutron activation analysis (INAA) relies on constant neutron flux densities throughout the activated samples. Although this concept is true for most typical samples, occasionally, the presence of highly neutron absorbing nuclides in the sample may cause a neutron flux density suppression which would ultimately lead to distorted results in the INAA. Here, we have investigated artificial samples with a high manganese (Mn) content. By adding aqueous gold solution, we introduced a liquid in-situ neutron flux monitor into the sample. An Mn content ≤ 50% shows little effect to the internal neutron flux density, however, the flux can be suppressed by ca. 20% when the Mn content reaches 63.2%.

The possibility of determining the 238 U content in solid samples of various compositions by instrumental neutron activation analysis (INAA) with a radionuclide neutron source based on 252 Cf was shown. The method is verified for aluminosilicate uranium-containing samples in the range from 10 to 300 ppm. The effect of the samples density and macrocomposition on the results of the uranium content determination by the INAA method was shown. Linear gamma radiation attenuation factor and the thermal neutrons interaction macroscopic cross section were calculated for studied samples. The applied approach makes it possible to take into account the influence of the sample’s density and macrocomposition and apply INAA for the uranium determination to a wide range of samples with various compositions.

•Chemical characterization of automobile windshield glasses for forensic studies.•External (in-air) PIGE using Ta as an external current normalizer for the quantification major (low Z) elements.•INAA using high reactor neutron flux for quantification of trace elements: transition and rare earth elements.•Quality assessment by analyzing the glass standard reference material (SRM).•Utilization of trace elemental concentrations for grouping studies by statistical analyses for forensic applications. Glass forensics is an important area in forensic crime investigations, wherein glass origin or source finding is necessary mainly through chemical composition. In the present work, Nuclear Analytical Techniques namely external (in air) Particle Induced Gamma-ray Emission (PIGE) and Instrumental Neutron Activation Analysis (INAA) were utilized for complete chemical characterization of twenty-five “as received” windshield glass samples of six car manufactures. Concentrations of four major elements (Si, Na, Mg and Al) by PIGE using proton beam and nineteen elements including sixteen trace elements by INAA using research reactor neutrons were determined. Both the methods were validated by analysing matrix matched glass certified (standard) reference materials. Trace elemental concentrations including rare earth elements (REEs) and ternary plot using concentrations of major, transition elements and REEs were utilized to obtain preliminary grouping of the analyzed glass samples. Statistical tools namely K-mean, Cluster Analysis and Principal Component Analysis (PCA) using trace elemental concentrations were utilized for grouping studies, important for forensic applications. Among these statistical analysis techniques, PCA results confirmed that windshield glasses from six manufactures clearly belong to six different groups.

In this study, two kinds of Artemisia plant, Artemisia campestris L. and Artemisia herba-alba Asso., collected from different locations in Djelfa province, Algeria, were subjected to an instrumental neutron activation analysis (INAA) in order to determine their essential and toxic elements for the first time. The obtained results for both types revealed the existence of twenty-one elements, namely, As, Ba, Br, Ca, Ce, Co, Cr, Cs, Eu, Fe, Hf, K, La, Na, Rb, Sb, Sc, Sm, Sr, Yb, and Zn, where, the elements K, Ca, Fe, and Na respectively showed a significant concentration. On the other hand, the tolerable daily intake (TDI) of the studied plants for an adult person per day was within the tolerance limits imposed by the World Health Organization (WHO). Hence, these findings might therefore be used to offer scientific basis for an optimum usage of the studied plants and so enriches the database of medicinal herbs.

An obsolete control unit of a fast transport (rabbit) system for short-time neutron activation analysis at the LVR-15 experimental reactor at Řež has been replaced. In the new system a PC is used to fully control the rabbit system and the subsequent gamma-ray spectrometry measurement. The modernization resulted in significant simplification of the operator work and improved documentation of the irradiation and spectra acquisition procedures. New nuclear safety features of the rabbit system are also described.

The elemental composition of twenty hot pepper ( Capsicum spp. L.) collections obtained from eight distinct agroecological locations across Ghana, were assessed by Instrumental Neutron Activation Analysis. The hot peppers fruits that were analysed contained five macroelements, Ca, Cl, K, Mg, Na, two microelements, Al, and Mn, and one trace element, Br. One collection from Volta region and three collections from the Northern region revealed elevated sodium contents in their fruits. In addition, the levels of Aluminium, Bromine, Calcium, Potassium and Sodium in fruits were found to be strongly positively correlated.

Instrumental neutron activation analysis (INAA) was employed to assay 32 minor and trace elements in bone of Bohemian Duke John of Görlitz (1370–1396) who suddenly died at the age 25 years for unknown reasons. Recently, histological examination of his illium bone was carried out, accompanied by histochemical staining reactions to learn about his health status. The INAA results disproved an elevated Al content indicated by the staining reaction with aluminon, but revealed elevated levels of Mn, As, Sb, and especially of Ag compared with literature values. The results are discussed in terms of toxicity of the above elements, especially whether their elevated levels could be the reason for Duke´s sudden death.

A feasibility study of gamma-gamma coincidence measurements in prompt gamma neutron activation analysis is carried out experimentally with a pulsed DT neutron generator, a polyethylene graphite cell and eight large NaI(Tl) scintillators. Detection limits are measured with multidimensional energy spectra created in gamma-gamma coincidence and compared to HPGe detector spectra. With a neutron emisison of 2.5 × 10 8 n.s −1 , the detection limit for sulfur is about 15 g in 20 min, while the detection limit is larger than 200 g when using the HPGe detector spectra. Processing the summ of up to three coincident gamma-ray energies highlights useful signal for a dysprosium sample, and allows for detecting permanent magnets containing 4% mass dysprosium within a rotor mock-up composed of stainless steel.

Recycling electronic waste (WEEE) is a fundamental aspect of the circular economy. To develop technology and assess its economic aspects, the composition characterization of the waste items is crucial. Neutron-based analytical techniques, such as the INAA, in-beam NAA, and PGAA, are applicable to measure the elemental composition of WEEE. These techniques are bulk representative and offer simultaneous determination of the relevant elements without sample dissolution. This study explores the suitability of neutron-based elemental analysis methods for measuring common WEEE items, e.g., printed circuit boards and integrated circuits. Matrix effects mostly related to the thermal neutron self-shielding, were identified and successfully corrected, ensuring accurate mass fraction measurements.