rss_2.0Nukleonika FeedSciendo RSS Feed for Nukleonika Feed W. Alexander Van Hook (1936-2023) radiation shielding properties of (x)BiO–(0.5 – x)ZnO–0.2BO–0.3SiO glass system<abstract> <title style='display:none'>Abstract</title> <p>Lead (Pb)-based materials are very effective in radiation shielding due to their high density of Pb. However, they pose health risks to humans because of the toxicity of lead. As a result, the investigation of radiation shielding properties of various lead-free glass materials has drawn a lot of attention from researchers. In this work, the γ radiation competence of the Bi<sub>2</sub>O<sub>3</sub>–ZnO–B<sub>2</sub>O<sub>3</sub>–SiO<sub>2</sub> glass network was investigated, for the first time in the 0.015–15 MeV energy range, using Phy-X/PSD and XCOM software systems. The results showed that 45Bi<sub>2</sub>O<sub>3</sub>–5ZnO–20B<sub>2</sub>O<sub>3</sub>–30SiO<sub>2</sub> glass sample has the highest linear attenuation coefficient, mass attenuation coefficient, and effective atomic number, and it has the lowest half-value layer, tenth-value layer, and mean-free path. Therefore, 45Bi<sub>2</sub>O<sub>3</sub>–5ZnO–20B<sub>2</sub>O<sub>3</sub>–30SiO sample is more effective on γ ray shielding than 10Bi<sub>2</sub>O<sub>3</sub>–40ZnO–20B<sub>2</sub>O<sub>3</sub>–30SiO, 20Bi<sub>2</sub>O<sub>3</sub>–30ZnO–20B<sub>2</sub>O<sub>3</sub>–30SiO, 30Bi<sub>2</sub>O<sub>3</sub>–20ZnO–20B<sub>2</sub>O<sub>3</sub>–30SiO, and 40Bi<sub>2</sub>O<sub>3</sub>–10ZnO–20B<sub>2</sub>O<sub>3</sub>–30SiO samples. The comparison of the results with the literature also revealed that the 45Bi<sub>2</sub>O<sub>3</sub>–5ZnO–20B<sub>2</sub>O<sub>3</sub>–30SiO glass sample is even more effective than some of Bi<sub>2</sub>O<sub>3</sub>-based glass systems, which were recently developed in the literature, by at least a factor of 2.</p> </abstract>ARTICLEtrue evidence of the long-term toxicity of Aeroxide P25 TiO nanoparticles in three mammalian cell lines despite the initial reduction of cellular mitochondrial activity<abstract> <title style='display:none'>Abstract</title> <p>We studied the effects of Aeroxide P25 titanium dioxide nanoparticles (TiO<sub>2</sub> NPs) with a diameter of 21 nm on induction of DNA damage and long-term survival of three human cell lines: hepatocellular liver carcinoma HepG2, colorectal adenocarcinoma HT29 and lung carcinoma A549. The endpoints examined were DNA breakage estimated by the comet assay and oxidative base damage recognized by formamide-pyrimidine glycosylase (FPG) estimated with the FPG<sup>+</sup> comet assay, frequencies of histone γH2AX foci and micronuclei, apoptosis, cell metabolic activity measured by mitochondrial activity (MTT) assay and long-term survival measured by colony-forming ability. Each cell line had a different pattern of DNA breakage and base damage vs. nanoparticle (NP) concentration and treatment time. There was no increase in the frequencies of histone γH2AX foci and micronuclei as compared to those in the untreated cells. In parallel with these results, no induction of apoptosis has been found in none of the cell lines tested. The reported experiments provided no evidence of the long-term <italic>in vitro</italic> toxicity of Aeroxide P25 TiO<sub>2</sub> NPs, despite a slight decrease in mitochondrial activity and cell survival during the first 72 h.</p> </abstract>ARTICLEtrue of the neutronic properties of the (Th-U)O, (Th-U)C, and (Th-U)N fuels in small long-life PWR cores with 300, 400, and 500 MW of power<abstract> <title style='display:none'>Abstract</title> <p>The neutronic characteristics of (Th-<sup>233</sup>U)O<sub>2</sub>, (Th-<sup>233</sup>U)C, and (Th-<sup>233</sup>U)N have been compared in small long-life pressurized water reactors (PWRs). Neutronic calculations were carried out at 300 MW<sub>th</sub>, 400 MW<sub>th</sub>, and 500 MW<sub>th</sub> with two cladding types: zircaloy-4 and ZIRLO (Zr low oxygen). They were performed using the Standard Reactor Analysis Code (SRAC) and JENDL-4.0 nuclide data, dividing the reactor core into three fuel zones with varying <sup>233</sup>U enrichment levels, ranging from 3% to 9% and fluctuating by 1%, employing the PIJ module at the fuel cell level and the CITATION module at the reactor core level. In addition, <sup>231</sup>Pa was added as burnable poison (BP). The (Th-<sup>233</sup>U)N fuel demonstrated superior criticality compared to the other fuel types, as it consistently achieves critical conditions throughout the reactor’s operating cycle with excess reactivity &lt;1.00% dk/k for several fuel configurations at the 300 MW<sub>th</sub> and 400 MW<sub>th</sub> power levels. Moreover, the (Th-<sup>233</sup>U)N and (Th-<sup>233</sup>U)C fuels exhibited similar and flatter power density distribution patterns compared to the (Th-<sup>233</sup>U)O<sub>2</sub> fuel. The power peaking factor (PPF) value was relatively higher for (Th-<sup>233</sup>U)O<sub>2</sub> fuel than the other two fuels. The (Th-<sup>233</sup>U)N fuel exhibited the most negative Doppler coefficient, followed by (Th-<sup>233</sup>U)C and (Th-<sup>233</sup>U)O<sub>2</sub> fuels. Analysis of burnup levels revealed that the (Th-<sup>233</sup>U)O<sub>2</sub> fuel achieved significantly higher burnup than the other two fuels.</p> </abstract>ARTICLEtrue tube signal conditioning for high-temperature applications<abstract> <title style='display:none'>Abstract</title> <p>Ionizing radiation detection in harsh environment conditions often requires additional signal processing to match the requirements of the commercial data readout systems. The subject of this paper is the design of the high-temperature (HT) signal conditioning module that ensures the applicability of scintillation detectors that utilize photomultiplier tubes (PMT) with moderate sampling rate instrumentation. The design was developed for the operation in HT environments (up to 120°C). In order to achieve the optimal signal shape, the module combines a charge amplifier and a low-pass filtering circuitry. An embedded power supply section makes it a complete, standalone unit requiring a single 12 V supplying line. A comprehensive analysis of the developed device, named “PreAmp Shape”, was conducted in order to prove the intended functionality over the different working conditions.</p> </abstract>ARTICLEtrue studies of plasma edge in W7-X with 3D FINDIF code<abstract> <title style='display:none'>Abstract</title> <p>Modelling of the plasma transport for inherently three-dimensional (3D) problems as in stellarators requires dedicated complex codes. FINDIF is a 3D multifluid plasma edge transport code that has been previously successfully used for the analysis of energy transport in the TEXTOR-DED tokamak [<xref ref-type="bibr" rid="j_nuka-2023-0011_ref_001">1</xref>], where 3D perturbations led to an ergodic structure of field lines in the plasma edge. The ongoing efforts to apply it meaningfully to Wendelstein 7-X (W7-X) plasma problems resulted in advancements in the main model and accompanying tools for mesh generation and post-processing. In order to verify the applicability of the code and to compare with the reported simulation (EMC3-EIRENE) and experimental (OP1.1) results, a series of simulations for varying plasma density, temperature and anomalous transport coefficients as well as for fixed input power were performed. The connection length pattern of FINDIF traced magnetic field lines on the limiter was reproduced and its impact on heat loads was confirmed. An increase in the peak heat load on the limiter with a rise in plasma density, temperature and anomalous plasma transport coefficients was observed. The decay lengths of density, electron temperature and heat flux did not change with density, and were decreasing with temperature and increasing with anomalous plasma transport coefficient, which was compared to the simple scrape-off layer (SOL) model.</p> </abstract>ARTICLEtrue degradation of CFCl, CFCl, and CFCl under electron beam irradiation<abstract> <title style='display:none'>Abstract</title> <p>Electron beam treatment technologies should be versatile in the removal of chlorofluorocarbons (CFCs) owing to their exceptional cross sections for the thermal electrons generated in the radiolysis of air. Humidity, dose rates, O<sub>2</sub> concentration, and CFC concentration influence the efficiency of the destruction process under electron beam treatment. Computer simulations have been used to theoretically demonstrate the destruction of chlorotrifluoromethane (CF<sub>3</sub>Cl), dichlorodifluoromethane (CF<sub>2</sub>Cl<sub>2</sub>), and trichlorofluoromethane (CFCl<sub>3</sub>) in the air (N<sub>2</sub> + O<sub>2</sub>: 80% + 20%) in room temperature up to a dose of 13 kGy. Under these conditions, it is predicted that the removal efficiency is in the order CF<sub>3</sub>Cl (0.1%) &lt; CF<sub>2</sub>Cl<sub>2</sub> (7%) &lt; CFCl<sub>3</sub> (34%), which shows the dependence of the process on the number of substituted Cl atoms. Dissociative electron attachment with the release of Cl<sup>–</sup> is the primary process initiating the destruction of CFCs from the air stream. Reactions with the first excited state of oxygen, namely, O(<sup>1</sup>D), and charge-transfer reactions further promote the degradation process. The degradation products can be further degraded to CO<sub>2</sub>, Cl<sub>2</sub>, and F<sub>2</sub> by prolonged radiation treatment. Other predicted products can also be removed through chemical processes.</p> </abstract>ARTICLEtrue design of the gamma blockers for the high-energy beam transport region of the European Spallation Source<abstract> <title style='display:none'>Abstract</title> <p>The European Spallation Source (ESS) is a collaboration of 13 European countries to build the world’s most powerful neutron source for research. The project, situated in the south of Sweden, is approaching the end of the construction phase, and the first scientific results are planned for 2023. This paper gives an overview of mechanical design of the gamma blockers (GBs) in the accelerator to target (A2T) and dump line (DmpL) sections. The presence of GBs in the beam line should limit the gamma radiation emitted from the activated tungsten target and beam dump to allow the safe access of the staff to the machine. The presented design allows for efficient operation and the same shutting time independently of the vacuum status.</p> </abstract>ARTICLEtrue exposure in kindergartens in one Bulgarian district<abstract> <title style='display:none'>Abstract</title> <p>The major part of the radiation dose that humans receive from natural radioactive sources is due to inhalation of radon and its decay products. The study focuses on radon concentration (CRn) investigation in kindergartens and nurseries in the district of Montana. The influence of building characteristics on CRn was evaluated. The measurement of the CRn was performed using passive detectors. The survey was carried out between December 2019 and May 2020 with a total number of 602 detectors. The average value of CRn in the premises of the studied kindergartens and nurseries in this district is 125 Bq·m<sup>−3</sup>, and the geometric mean (GM) value is 88 Bq·m<sup>−3</sup>. The buildings that have built ventilation and sewerage systems have lower CRn. The effective doses of the children and workers were evaluated in order to assess the radon exposure.</p> </abstract>ARTICLEtrue of a Compton backscattering wall defects detection device using the Monte Carlo method<abstract> <title style='display:none'>Abstract</title> <p>In view of the shortcomings of traditional wall defect detection methods, such as small detection range, poor accuracy, non-portable device, and so on, a wall defects detection device based on Compton backscattering technology is designed by Monte Carlo method, which is mainly used to detect the size and location information of defects in concrete walls. It mainly consists of two parts, the source container and the detection system: first, through the simulation and analysis of the parameters such as the receiving angle of the backscattered particles and the rear collimating material of the detector, the influence of the fluorescent X-ray peak of the detector collimating material on the backscattered particle counts is eliminated and the detected error is reduced; second, the ring array detector design, compared with single array detector and surface array detector, can facilitate real-time detection of defect orientation, expanding the single scan range and improving the detection efficiency. After simulation and comparative analysis, the relevant optimal parameters are obtained: the object is detected using a Cs-137 <italic>γ</italic>-ray source with an activity of 6 mCi, and a ring detector consisting of four 0.5-inch cube-shaped CsI scintillator detectors is placed at 150° to receive the backscattered photons. The simulation analysis using the Monte Carlo FLUKA program showed that the maximum depth of wall defect detection is 8 cm, the maximum error fluctuation range of defect depth and thickness is ±1 cm, the overall device weight is &lt;20 kg, and the measurement time is &lt;5 min.</p> </abstract>ARTICLEtrue of low-temperature plasmas formed in low-density gases surrounding laser-produced plasmas<abstract> <title style='display:none'>Abstract</title> <p>Low-temperature plasma production is possible as a result of photoionization using high-intensity extreme ultraviolet (EUV) and soft X-ray (SXR) pulses. Plasma of this type is also present in outer space, e.g., aurora borealis. It also occurs when high-velocity objects enter the atmosphere, during which period high temperatures can be produced locally by friction. Low-temperature plasma is also formed in an ambient gas surrounding the hot laser-produced plasma (LPP). In this work, a special system has been prepared for investigation of this type of plasma. The LPP was created inside a chamber filled with a gas under a low pressure, of the order of 1–50 mbar, by a laser pulse (3–9 J, 1–8 ns) focused onto a gas puff target. In such a case, the SXR/EUV radiation emitted from the LPP was partially absorbed in the low-density gas. In this case, high- and low-temperature plasmas (<italic>T</italic><sub>e</sub> ~100 eV and ~1 eV, respectively) were created locally in the chamber. Investigation of the EUV-induced plasmas was performed mainly using spectral methods in ultraviolet/visible (UV/VIS) light. The measurements were performed using an echelle spectrometer, and additionally, spatial–temporal measurements were performed using an optical streak camera. Spectral analysis was supported by the PGOPHER numerical code.</p> </abstract>ARTICLEtrue and FREE access to plasma physics experiments<abstract> <title style='display:none'>Abstract</title> <p>Remote controlled laboratories had a great push during the COVID-19 pandemic. In fact, they were already out there but lacking in visibility. This external trigger pushed the academy to face a global challenge to start offering remote experiments more consistently and maturely. Instituto Superior Técnico (IST) has been offering several remote experiments since 2000 but with the need for an update due to technological aging. As such, the framework for remote experiments in education (FREE) was created based on new web technologies. In addition to the most diverse experiments that had already been developed, FREE includes two experiments that aimed at advanced-level physics students: the Langmuir probe and the electromagnetic (EM) cavity. Both allow users to configure the various parameters and to access the results in real time or check back later. All this access is done using a browser (on a PC or mobile phone) without the need to install additional software. The results of an experimental execution are stored in a database and are downloadable, allowing users to do various analyses and to determine the corresponding plasma density and temperature. In this paper, we will introduce how FREE was used in the implementation of both experiments and give an insight into their didactic approach, such as: (i) how to perform an experimental execution, (ii) the typical data set obtained with, and (iii) the corresponding analysis necessary for the user to retrieve information from it.</p> </abstract>ARTICLEtrue of Thomson parabola spectrometer in various laser-plasma- and laser-fusion-related experiments<abstract> <title style='display:none'>Abstract</title> <p>The Thomson parabola spectrometer (TPS) [<xref ref-type="bibr" rid="j_nuka-2023-0005_ref_001">1</xref>] is a well-known, universal diagnostic tool that is widely used in laser plasma experiments to measure the parameters of accelerated ions. In contrast to other popular ion diagnostics, such as semiconductor detectors or ion collectors, the TPS is not greatly affected by electromagnetic pulses generated during high-power laser interaction with matter and can be tuned to acquire data in various energy ranges of accelerated ions, depending on the goal of the experiment. Despite the many advantages of this diagnostic device, processing the collected data is a difficult task and requires a lot of caution during interpretation of gathered results. In this work, we introduce the basic principles of operation and data analysis based on the numerical tool created specifically for the TPS designed at the Institute of Plasma Physics and Laser Microfusion, present a range of data obtained during various recent experiments in which our TPS was used, and highlight the difficulties in data analysis depending on the purpose of the experiment and the experimental setup.</p> </abstract>ARTICLEtrue and local parameters of self-compressed plasma streams in external magnetic field<abstract> <title style='display:none'>Abstract</title> <p>The influence of the external axial magnetic field on pinching plasma flows generated by a magnetoplasma compressor (MPC) has been studied using magnetic and electric probes. In the presence of an external magnetic field, temperature measurements show two groups of electrons with different temperatures near the plasma stream core. The external magnetic field leads to a noticeable increase in the electric current in the plasma stream, electron temperature, and the formation of the current-sheet-like structure observed in the MPC for the first time.</p> </abstract>ARTICLEtrue microwave refraction to determine local inhomogeneities of a rotating plasma<abstract> <title style='display:none'>Abstract</title> <p>To determine the local inhomogeneities of a rotating plasma, the method based on microwave refraction was used. The method is based on spectral and correlation analysis of the reflected signals from the rotating plasma layer at normal and inclined microwave incidence. This method allowed us to determine local inhomogeneities of plasma electron density, angles of azimuthal displacement of grooves, and its angular frequency of rotation. Using an additional 4th horn antenna, in contrast to previous works, it was possible to find and analyze two regions with azimuthal inhomogeneities in the rotating plasma. Analysis of the reflected signals shows the presence of four grooves, and the angular frequency of rotation <italic>ω</italic> = 1.16 × 10<sup>4</sup> rad/s was also determined.</p> </abstract>ARTICLEtrue energy partitions in electron–ion PIC simulations of ABC fields<abstract> <title style='display:none'>Abstract</title> <p>We explore the kinetic energy partitions between electrons and ions in the 2-D magnetostatic equilibria called Arnold–Beltrami–Childress (ABC) fields, using particle-in-cell (PIC) numerical simulations. We cover a wider range of ion–electron temperature combinations and get different results compared to previous studies of the Harris-layer-type magnetic reconnection simulations. We find that the initial ion–electron enthalpy ratio is an important indicator. The particle species that dominates the total enthalpy will also dominate the kinetic energy gains and the momentum distribution peaks, but the other species have higher nonthermal energy fractions because both species show similar maximum energies.</p> </abstract>ARTICLEtrue derived from -terphenyl in the methyltributylammonium bis[(trifluoromethyl)sulfonyl]imide ionic liquid saturated with carbon dioxide: Pulse radiolysis study<abstract> <title style='display:none'>Abstract</title> <p>Radiation-induced processes in ionic liquid (IL) methyltributylammonium bis[(trifluoromethyl)sulfonyl] imide ([MeBu<sub>3</sub>N][NTf<sub>2</sub>]) solutions containing <italic>p</italic>-terphenyl (TP) and saturated with carbon dioxide (CO<sub>2</sub>) were studied using nanosecond pulse radiolysis technique with UV-vis detection. The transient absorption spectra generated in these solutions were assigned to TP radical anions (TP<sup>•−</sup>) and triplet excited states (<sup>3</sup>TP*). Saturation of [MeBu<sub>3</sub>N][NTf<sub>2</sub>] solutions with carbon dioxide efficiently takes out presolvated electrons <inline-formula> <alternatives> <inline-graphic xmlns:xlink="" xlink:href="graphic/j_nuka-2022-0007_ieq_001.png"/> <mml:math xmlns:mml="" display="inline"><mml:mrow><mml:mrow><mml:mo stretchy="false">(</mml:mo><mml:mrow><mml:msubsup><mml:mtext>e</mml:mtext><mml:mrow><mml:mtext>presolv</mml:mtext></mml:mrow><mml:mo>−</mml:mo></mml:msubsup></mml:mrow><mml:mo stretchy="false">)</mml:mo></mml:mrow></mml:mrow></mml:math> <tex-math>( {{\rm{e}}_{{\rm{presolv}}}^ - } )</tex-math> </alternatives> </inline-formula> and solvated electrons <inline-formula> <alternatives> <inline-graphic xmlns:xlink="" xlink:href="graphic/j_nuka-2022-0007_ieq_002.png"/> <mml:math xmlns:mml="" display="inline"><mml:mrow><mml:mrow><mml:mo stretchy="false">(</mml:mo><mml:mrow><mml:msubsup><mml:mtext>e</mml:mtext><mml:mrow><mml:mtext>solv</mml:mtext></mml:mrow><mml:mo>−</mml:mo></mml:msubsup></mml:mrow><mml:mo stretchy="false">)</mml:mo></mml:mrow></mml:mrow></mml:math> <tex-math>( {{\rm{e}}_{{\rm{solv}}}^ - } )</tex-math> </alternatives> </inline-formula> . On the other hand CO<sub>2</sub> is not a scavenger of excited states of TP (<sup>1</sup>TP*, <sup>3</sup>TP*), which in the reaction with triethylamine (TEA) leads to the formation of TP<sup>•−</sup>.</p> </abstract>ARTICLEtrue Sr quantification method based on the Bateman equation for routine laboratory work<abstract> <title style='display:none'>Abstract</title> <p>Artificially introduced into the environment <sup>90</sup>Sr is highly radiotoxic, so its content levels in foodstuff and biota require constant monitoring for radiological protection. Most analytical procedures used for <sup>90</sup>Sr determination are time-consuming, and therefore, a faster approach is needed. Employing the Bateman equation enables more efficient exploitation of the secular equilibrium between <sup>90</sup>Sr and its daughter radionuclide <sup>90</sup>Y in the calculations. This article describes a method for computing the <sup>90</sup>Sr activity concentration, while accounting for <sup>90</sup>Y activity. The developed approach was tested and validated in terms of its applicability in everyday analysis.</p> </abstract>ARTICLEtrue upgrading of the nanosecond pulse radiolysis setup and construction of laser flash photolysis setup at the Institute of Nuclear Chemistry and Technology in Warsaw, Poland<abstract> <title style='display:none'>Abstract</title> <p>Modification of pulse radiolysis (PR) setup and construction of a new laser flash photolysis (LFP) setup at the Institute of Nuclear Chemistry and Technology (INCT) is described. Both techniques are dedicated to studying fast reactions in real time by direct observation of transients. Time resolution of the PR setup at INCT was ~11 ns, limited by the duration of the electron pulse. Implementation of a new spectrophotometric detection system resulted in a significant broadening of experimental spectral range with respect to the previous setup. Noticeable reduction of the noise-to-signal ratio was also achieved. The LFP system was built from scratch. Its time resolution was ~6 ns, limited by the duration of a laser pulse. LFP and PR were purposely designed to share the same hardware and software solutions. Therefore, components of the detection systems can be transferred between both setups, significantly lowering the costs and shortening the construction/upgrading time. Opened architecture and improved experimental flexibility of both techniques were accomplished by implementation of Ethernet transmission control protocol/Internet protocol (TCP/IP) communication core and newly designed software. This is one of the most important enhancements. As a result, new experimental modes are available for both techniques, improving the quality and reducing the time of data collections. In addition, both systems are characterized by relatively high redundancy. Currently, implementation of new equipment into the systems hardly ever requires programming. In contrast to the previous setup, daily adaptations of hardware to experimental requirements are possible and relatively easy to perform.</p> </abstract>ARTICLEtrue of intrapulse energy switching in standing-wave electron linac<abstract> <title style='display:none'>Abstract</title> <p>For the development of an effective cargo-scanning system, an intrapulse energy switching has been tested at the National Centre for Nuclear Research (NCBJ) with the possibility to change the beam energy within a 4 μs pulse of the linear electron accelerator (linac). Modification of the electron energy is achieved through the beam-loading effect in a standing-wave accelerating structure equipped with a triode gun. Construction of the machine and the achieved results are presented in this article.</p> </abstract>ARTICLEtrue