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a method of instrumental neutron activation analysis (INAA) of pure rhodium has been developed, which does not require transferring the sample into a solution to determine the elemental composition. The method allows determining about 40 impurity elements with detection limits of n×10 -5 - n×10 -9 % of mass at S r = 0.1-0.12. The method can be used to determine the microimpurity composition of ultra-pure rhodium..

Neutron Activation Analysis (NAA) is the most common technique used in research reactors worldwide. The IAEA aims to enhance quality assurance in NAA laboratories by supporting annual proficiency testing, by developing and offering relevant e-learning as well as specialized publications. This publication, which is based on the most up to date relevant ISO guides and international practices, provides practical guidance on quality assurance (QA) and quality control (QC) in NAA laboratories. It is intended to be used in the day-to-day work of NAA at research reactors. Potential sources of errors and associated QA/QC actions are detailed for all main areas of NAA practice. Easy to use tables are provided, intended for direct reference in the laboratory.

Seed priming uses treatments to improve seed germination and thus potentially increase growth and yield. Low-cost, environmentally friendly, effective seed treatment remain to be optimized and tested for high-value specialty crop like watermelon ( Citrullus lanatus ) in multi-locations. This remains a particularly acute problem for triploids, which produce desirable seedless watermelons, but show low germination rates. In the present study, turmeric oil nanoemulsions (TNE) and silver nanoparticles (AgNPs) synthesized from agro-industrial byproducts were used as nanopriming agents for diploid (Riverside) and triploid (Maxima) watermelon seeds. Internalization of nanomaterials was confirmed by neutron activation analysis, transmission electron microscopy, and gas chromatography-mass spectrometry. The seedling emergence rate at 14 days after sowing was significantly higher in AgNP-treated triploid seeds compared to other treatments. Soluble sugar (glucose and fructose) contents were enhanced during germination in the AgNP-treated seeds at 96 h. Seedlings grown in the greenhouse were transplanted at four locations in Texas: Edinburg, Pecos, Grapeland, and Snook in 2017. At Snook, higher yield 31.6% and 35.6% compared to control were observed in AgNP-treated Riverside and Maxima watermelons, respectively. To validate the first-year results, treated and untreated seeds of both cultivars were sown in Weslaco, Texas in 2018. While seed emegence and stand establishments were enhanced by seed priming, total phenolics radical-scavenging activities, and macro- and microelements in the watermelon fruits were not significantly different from the control. The results of the present study demonstracted that seed priming with AgNPs can enhance seed germination, growth, and yield while maintaining fruit quality through an eco-friendly and sustainable nanotechnological approach.

Heavy metals are one of the most hazardous inorganic contaminants of both water and soil environment composition. Normally, heavy metals are non-biodegradable in nature because of their long persistence in the environment. Trace amounts of heavy metal contamination may pose severe health problems in human beings after prolonged consumption. Many instrumental techniques such as atomic absorption spectrophotometry, inductively coupled plasma-mass spectrometry, X-ray fluorescence, neutron activation analysis, etc. have been developed to determine their concentration in water as well as in the soil up to ppm, ppb, or ppt levels. Recent advances in these techniques along with their respective advantages and limitations are being discussed in the present paper. Moreover, some possible remedial phytoremediation approaches (phytostimulation, phytoextraction, phyotovolatilization, rhizofiltration, phytostabilization) have been presented for the removal of the heavy metal contamination from the water and soil environments.

•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.

[See PDF for image] Fig. 2 Opening The Young Scientists’ Award of the International Committee of Activation Analysis this year was presented to Iaroslav Meleshenkovskii from the Jülich Center for Neutron Sciences, whose paper is also included here. Instrumental neutron activation analysis Facilities k0-based neutron activation analysis Comparison to other methods Prompt gamma activation analysis Applications Activation analysis using fast neutrons and other particles Reference materials Neutron depth profiling 46 oral presentations together with eleven plenary talks were presented, while 45 posters were on display in the two afternoon poster sessions (Fig. 3). [See PDF for image] Fig. 3 Presentation of the Hevesy Medal Award, Balázs Réffy Director General of Akadémiai Kiadó, Amares Chatt Canada, also Chair of JRNC Board of the Hevesy Award, Elisabete A. De Nadai Fernandes the awardee, Zsolt Révay Editor-in-Chief of Journal of Radioanalytical and Nuclear Chemistry, the organizer of the conference The social programs included guided walks in the castle district and a dinner at the Feneketlen (Bottomless) lake.

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.

Kartini reactor in Yogyakarta is a nuclear reactor with a low thermal power of 100 kW that is mainly used for education, training, and research. For that purpose, measuring neutron flux and controlling the power are important operational parameters. The Fission Chamber (FC) type of detector is the main component in the reactor operation and safety system that measures the neutron flux in the outer reactor core. As the FC detector is placed in a fixed location, a numerical calculation model is needed to know the neutron flux in all outer core regions. In this study, the MCNPX code is used. The first step is to validate the model with experimental measurement. The objective of the present study is to obtain a validated model by comparing calculations using MCNPX with measurements using gold foil activation (Neutron Activation Analysis technique). The computational model tested showed promising results with an average difference compared to the gold foil activation method of about 23%. Further research can be done using more gold foil samples or foils from other materials to see the consistency of measurements or minimize the measurement difference.

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%.

In this work, we extend our previously published Monte Carlo simulation model of the Dingo thermal neutron beamline at the Australian Centre for Neutron Scattering model by (1) including a sapphire crystal filter in the model, and (2) utilising the NCrystal package to simulate thermal neutron interactions with the crystalline structure. In addition to previous experimental measurements performed in the beamline’s high-resolution mode, the beam was experimentally characterised in its high-intensity mode upstream from the sample stage (at the tertiary shutter wall exit) and these measurements were used as inputs for the model. The planar neutron distributions were optimised at both the sample stage and tertiary shutter wall exit, and model predictions were validated against experimental gold wire activation measurements. For both configurations—with and without the sapphire filter—we measured neutron fluxes, and performed neutron activation analysis using 11 materials to improve the accuracy of the neutron spectrum in the model relative to the original version. Using the optimised spectrum, we simulated out-of-beam neutron spectra that were further used as the initial input in unfolding code to explore the capability of the current solution to accurately reproduce the experimental results. The normalised neutron planar distribution from the simulation was on average within 2% at the centre, and 6% and 24% at the penumbra of the experimental results at the tertiary shutter wall exit and sample stage, respectively. The specific activities predicted by the refined model were within an average of 13% and 5% of the experimentally measured activities with and without the sapphire filter, respectively. We observed a decrease of around 45% in thermal neutron flux when the sapphire filter is used, which has been reproduced by the model. The maximum value of the logarithm of the ratio of simulated to experimental out-of-beam neutron spectra across 8 locations was 0.6 compared to 2.0 in the previous work, resulting in an average normalised root mean squared error between the unfolded spectrum and experimental measurements of 5% and 9% with and without the filter, respectively. Without the sapphire filter, the optimised predicted in-beam neutron spectrum consists of around 59% thermal, 21% epithermal and 20% fast neutrons, while the addition of the filter provides an almost pure (approximately 98%) thermal neutron beam.