Showing papers in "World Journal of Nuclear Science and Technology in 2013"
TL;DR: Using gamma-ray spectrometry, the activity concentration of naturally occurring radionuclides was determined in sand beaches samples from different areas in Guarapari, Espirito Santo state, from Brazil as mentioned in this paper.
Abstract: Using gamma-ray spectrometry, the activity concentration of naturally occurring radionuclides 226Ra, 212Pb, 214Pb, 232Th, and 40K was determined in sand beaches samples from different areas in Guarapari, Espirito Santo state, from Brazil. The absorbed dose rates and annual effective dose were calculated and the results were compared with the internationally accepted values as well as others high background radiation areas (HBRAs). The activity concentration of the 232Th in Areia Preta as well as the absorbed dose rates and annual effective dose were higher than the others regions compared. The results show that Areia Preta in Guarapari has higher background found in beaches in world. This work is part of a research project for the natural background determination of the Brazilian coast.
16 citations
TL;DR: The proposed equipment makes it possible to verify the complicated multichannel detection systems without having the radioactive experimental tests, and is a low cost instrumentation due to the FPGA-based construction.
Abstract: The present paper describes a multichannel digital random pulse generator implemented in a 65-nm FPGA device. The random time interval generation is based on inverse transformation method. The output pulse generation rate, pulse width and the probability distribution function (PDF) of each channel might be individually selected by the computer through a USB cable connection. Statistical properties of the output channels can be adjusted and recorded in a fully dynamic flexible manner. The Poisson and uniform PDFs were tested and implemented for up to eight different channels in experiment, however, the implementation of any arbitrary PDF is possible by programming capability of the device as well. Detailed experimental results are expressed in the manuscript. The proposed equipment makes it possible to verify the complicated multichannel detection systems without having the radioactive experimental tests. This is a low cost instrumentation due to the FPGA-based construction.
15 citations
TL;DR: In this paper, a diagram of nuclear facility hazard has been proposed to analyze the effect of potential energy on reactor facility safety/hazard, and a certain interest on the electricity cost for making payments in a special insurance fund assigned to compensate the expenses for elimination of consequences of a possible accident.
Abstract: Potential (non-nuclear) energy stored in reactor facility coolant is a crucial factor determining the NPP safety/hazard characteristics as it is inherent property of the material and cannot be changed. Enhancing safety of the NPP with traditional type reactor facilities, in which potential energy is stored in large quantities, requires buildup of the number of safety systems and in-depth defense barriers, which reduce the probability of severe accidents (but do not exclude the opportunity of their realization) and seriousness of their consequences. Keeping the risk of radioactivity release for different type reactor facilities at a same level of social acceptability, the number of safety systems and in-depth defense barriers, which determine essentially the NPP economical parameters, can be reduced with diminishing the potential energy stored in the reactor facility. To analyze the effect of potential energy on reactor facility safety/hazard, a diagram of reactor facility hazard has been proposed. It presents a probability of radioactivity release as a function of radioactivity release values for reactor facilities with identical radiation potential, which differ by values of potential energy stored in coolant. It is proposed to account NPP safety/hazard effect on economics by adding a certain interest on the electricity cost for making payments in a special insurance fund assigned to compensate the expenses for elimination of consequences of a possible accident.
15 citations
TL;DR: In this paper, a study of the room temperature Mossbauer spectrum, powder X-ray diffraction, energy dispersive Xray spectroscopy, and magnetic measurements of a sample of black magnetic sand collected on the seashore of the town of Ladispoli is performed.
Abstract: The study of natural magnetic sands is instrumental to investigate the geological aspects of their formation and of the origin of their territory. In particular, Mossbauer spectroscopy provides unique information on their iron content and on the oxidation state of iron in their mineral composition. The Italian coast on the Mediterranean Sea near Rome is known for the presence of highly magnetic black sands of volcanic origin. A study of the room temperature Mossbauer spectrum, powder X-ray diffraction, energy dispersive X-ray spectroscopy, and magnetic measurements of a sample of black magnetic sand collected on the seashore of the town of Ladispoli is performed. This study reveals magnetite as main constituent with iron in both tetrahedral and octahedral sites. Minor constituents are the iron minerals hematite and ilmenite, the iron containing minerals diopsite, gossular, and allanite, as well as ubiquitous sanidine, quartz, and calcite.
12 citations
TL;DR: In this paper, the activity concentrations of natural radionuclides 226Ra, 232Th and 40K in bauxite ore, alumina, dross tailing, aluminium scraps and soil samples collected from an aluminium industry in Nigeria were determined by gamma ray spectroscopy method.
Abstract: The activity concentrations of natural radionuclides 226Ra, 232Th and 40K in bauxite ore, alumina, dross tailing, aluminium scraps and soil samples collected from an aluminium industry in Nigeria were determined by gamma ray spectroscopy method. The mean values of 226Ra, 232Th and 40K content of the samples ranged from 16 ± 6 (alumina) to 31 ± 10 (scrap), 41 ± 0.12 (scrap) to 134 ± 21(bauxite) and 47 ± 14 (bauxite) to 354 ± 8 (scrap) Bq·kg-1, respectively. The mean activity concentrations of 226Ra and 40K in all the samples are lower than the world average for soil while 232Th is higher with the exception of alumina and scrap. As a measure of radiation hazard to the occupational workers and the members of the public, the radium equivalent activities and external gamma dose rates due to the radionuclides at 1 m above ground surface were calculated. The radium equivalent activities which varied between 88 ± 10 (alumina) and 222 ± 34 (bauxite) Bq·kg-1 are within the safety recommended limit of 370 Bq·kg-1. The mean annual effective doses calculated from the absorbed dose rates in air were between 54 ± 6 (alumina) and 134 ± 20 (bauxite) μSv·y-1, which is lower than the 1 mSv·y-1 recommended for the general public. The annual gonadal dose equivalent of all the samples with the exception of alumina was higher than the world average for soil.
12 citations
TL;DR: The present situation in Poland and Europe, regarding electric power generation by source, is discussed in this article, where the results of the implementation of EU competitive-low-carbon economy policy in some most developed countries in the continent, have given already good experimental data for evaluation of this strategy.
Abstract: The present situation in Poland and Europe, regarding electric power generation by source, is discussed in the paper. The results of the implementation of EU competitive-low-carbon economy policy in some most developed countries in the continent, have given already good experimental data for evaluation of this strategy. Analysis of the reports provided by official sources for Germany, Denmark and Finland is a base for EU energy policy evaluation. The combustion technologies will be a main energy sources for many years from now. Therefore effects of fossil fuels and biomass combustion on the environment are presented briefly. Finally, the developments regarding Polish Nuclear Energy Programme are overviewed.
11 citations
TL;DR: A new production method of no-carrier-added 64Cu was tested using a new target prepared by electroplating of Ni on a silver layer (thickness 35 μm) previously electroplated on a pure copper target support, which meets cost effective production and quality of the produced 64Cu criteria.
Abstract: A new production method of no-carrier-added 64Cu was tested using a new target prepared by electroplating of Ni on a silver layer (thickness 35 μm) previously electroplated on a pure copper target support. This method meets cost effective production and quality of the produced 64Cu criteria. The quality of the electroplated layers has been tested under the bombardment by more than 200 μA of proton beam using water cooled target system. A separation and purification setup was elaborated to produce high quantity and high specific activity of 64CuCl2 suitable for labeling different ligands in order to be used in therapy and diagnosis. A semi-automated target dissolution and separation system has been developed and achieved for 64Cu production. The separation chemistry is based on a chromatographic column system.
9 citations
TL;DR: In this paper, the use of variance reduction techniques (VRTs) for the simulation of a clinical linear electron accelerator (LINAC) was investigated, and a combination between VRTs and PS was also analyzed.
Abstract: Variance reduction techniques (VRTs) have been tremendously successful when applied to Monte Carlo radiation transport codes for which the computation time constitutes an important and a problematic parameter. In fact, many Monte Carlo calculations absolutely require variance reduction methods to achieve practical computation times. The MCNPX code has a fairly rich set of variance reduction techniques; the most known are transport cutoffs, interaction forcing, Bremsstrahlung splitting and Russian roulette. Also, the use of a phase space seems to be appropriate to reduce enormously the computing time. This work deals with the use of VRTs provided by MCNPX code for the simulation of a clinical linear electron accelerator (LINAC). Differences between various sets of VRTs are investigated. Combination between VRTs and PS is also analyzed during this study. Analysis showed that the use of VRTs and PS improve the simulation efficiency by a factor greater than 700. Finally, experimental curves of depth-dose and dose profile performed in a homogeneous water phantom are compared to dose distributions computed by use of MCNPX Monte Carlo code.
8 citations
TL;DR: In this article, the diffusion of 99Tc in Beishan granite at temperatures from 25 to 55 was studied with laboratory small scale diffusion devices, and the experimental data were fitted with a finite difference scheme to get the effective diffusion coefficient (De) of
Abstract: In the safety assessment of a potential site for high-level radioactive wastes (HLW) disposal, the investigation on the geochemical behaviors of key radionuclides with the possibility for releasing from the potential repository is an important aspect Due to the high mobility of technetium under most repository conditions, lots of research works were performed to investigate the diffusion of technetium in different potential rocks In spite of these studies, there remains a lack of data addressing temperature effects In this paper, the diffusion of 99Tc in Beishan granite at temperatures from 25℃ to 55℃ was studied with laboratory small scale diffusion devices The experimental data were fitted with a finite difference scheme to get the effective diffusion coefficient (De) of The results indicated that the relationship of De with temperatures could be described as the modified Stokes-Einstein equation, and the formation factor of Beishan granite was constant in the temperature range of 25℃ - 55℃ with the value of (391 ± 177) × 10-4
8 citations
TL;DR: In this article, the authors used a photon-counting X-ray computed tomography (CT) using an energy-discrimination 64-channel cadmium-telluride (CdTe) line detector.
Abstract: One of the issues in the aluminum-alloy die casting industry is the space occurring inside the casting, and the improvement of the verification technology is expected. The purpose of this research is to seal holes inside the aluminum metal by resin and verify them by photon-counting X-ray computed tomography (CT) using an energy-discrimination 64-channel cadmium-telluride (CdTe) line detector. Moreover, it is important to estimate the image of the effective atomic number and the electronic density by the energy mapping of the attenuation coefficient utilizing photon-counting X-ray CTto distinguish both the aluminum metal and the resin filler in the aluminum hole. As a result, the energy discrimination of the resin filler in the space of aluminum casting has been attained. We could observe the atomic number image utilizing dual-energyX-ray CTmethod with the 64-channel CdTe photon-counting detector.
8 citations
TL;DR: The specific radioactivity of several building materials used in France, which is considered a direct exposure to radiation, has been assessed by γ-ray spectrometry as mentioned in this paper, and the results showed that the materials examined would not contribute a significant radiation exposure for an occupant and thus are acceptable for construction.
Abstract: The specific radioactivity of several building materials used in France, which is considered a direct exposure to radiation, has been assessed by γ-ray spectrometry. Corrected for coincidence summing and self-absorption effects, the values for 226Ra, 232Th and 40K were in the ranges 4 - 56, 3 - 72 and 9 - 1136 Bq·kg-1, respectively. The samples were found to have radium-equivalent activities between 5 and 245 Bq·kg-1. Values of 0.02 - 0.67 for the external and 0.03 - 0.82 for the internal hazard indexes were estimated. The calculated absorbed dose in air agrees closely with MCNPX simulations. The conversion of absorbed dose to annual effective dose gave values between 0.03 - 1.09 mSv·y-1. All these values are below action limits recommended by the International Commission on Radiological Protection. The materials examined would not contribute a significant radiation exposure for an occupant and thus are acceptable for construction.
TL;DR: In this article, the authors considered the time dependent neutron diffusion equation for one energy group in cylinder coordinates, assuming translational symmetry along the cylinder axis, and solved analytically applying the Hankel transform in the radial coordinate r.
Abstract: We consider the time dependent neutron diffusion equation for one energy group in cylinder coordinates, assuming translational symmetry along the cylinder axis. This problem for a specific energy group is solved analytically applying the Hankel transform in the radial coordinate r. Our special interest rests in the build-up factor for a time dependent linear neutron source aligned with the cylinder axis, which in the limit of zero decay constant reproduces also the static case. The new approach to solve the diffusion equation by integral transform technique is presented and results for several parameter sets and truncation in the solution for the flux and build-up factor are shown and found to be compatible to those of literature [1,2].
TL;DR: In this paper, it was shown that the capture and fission cross-sections of 238U and 239Pu increase with temperature within 1000 K - 3000 K range, in contrast to those of 235U, that under certain conditions may lead to the so-called blow-up modes, stimulating the anomalous neutron flux and nuclear fuel temperature growth.
Abstract: It is shown that the capture and fission cross-sections of 238U and 239Pu increase with temperature within 1000 K - 3000 K range, in contrast to those of 235U, that under certain conditions may lead to the so-called blow-up modes, stimulating the anomalous neutron flux and nuclear fuel temperature growth. Some features of the blow-up regimes in neutronmultiplying media are discussed.
TL;DR: Dose rates calculations, in PMMA dosimeters, placed in the vicinity of the Tunisian 60Co gamma ray irradiator, have been achieved using a pencil like model, in good agreement with recent experimental data.
Abstract: Dose rates calculations, in PMMA dosimeters, placed in the vicinity of the Tunisian 60Co gamma ray irradiator, have been achieved using a pencil like model. The obtained results are in good agreement with recent experimental data. Moreover, in this work we determine also the conversion factor between the dose rate deposited in a PMMA dosimeter and the one deposited in a reel medium. This factor is used to determine the dose deposited in a real irradiated medium such as foodstuff products.
TL;DR: In this paper, the binding energy of α-particles was found to be larger than any other combination of four nucleons, and the bounding energy of an α particle is larger than that of any other particle.
Abstract: The saw-tooth phenomenon on the binding energy curve of N = Z nuclei is due to the low binding energy between the α-particles. It was suspected by Gamow to be of van der Waals type, found here to be deuteron bonds. The binding energy per nucleon, in absolute value, of an α-particle is larger than any other combination of 4 nucleons. Therefore, the binding energy per nucleon is low for odd-odd N = Z nuclei and maximum for even-even N = Z nuclei. The assumption of N = Z nuclei to be an assembly of α-particles and deuteron bonds predicts the binding energy of the 32 first N = Z nuclei with a rms deviation of 0.25 MeV.
TL;DR: In this article, the feasibility of development of an alternative accident monitoring via well-known noise diagnostics methods is proposed and demonstrated, and the possibility of identification of reactor accident conditions using temperature and pressure fluctuations, noise of the neutron and gamma field is considered on the basis of research achievements in reactor noise.
Abstract: Knowledge and control of the thermo-hydraulic conditions in the reactor is required for the effective accident management. Dedicated and qualified for harsh environment instrumentation has to be in place for this purpose. Experience of the Fukushima Dai-ichi plant and the lessons learned from the European stress tests demonstrated that alternative and divers tools and methods are needed for the identification of reactor condition in extreme situations. In the paper the feasibility of development of an alternative accident monitoring via well-known noise diagnostics methods is proposed and demonstrated. The possibility of identification of reactor accident conditions using temperature and pressure fluctuations, noise of the neutron and gamma field is considered on the basis of research achievements in reactor noise. As an example the use of pressure fluctuations for accident monitoring is presented.
TL;DR: In this paper, the structure function, the EMC ratio, and the lepton scattering cross section in the convolution nuclear theory framework for 4He and 12C nuclei were extracted.
Abstract: This paper is an effort to extract the structure function, the EMC ratio, and the lepton scattering cross section in the convolution nuclear theory framework for 4He and 12C nuclei. We suppose that, in conventional approach, based on harmonic oscillator model, one could consider for a nucleus shell different hw parameters which are associated with the square root of the mean radius of the nucleus shells. We use GRV free nucleon structure function, which has good agreement with the proton and neutron structure function, extracted from experimental results. In addition, the lepton scattering cross sections of 4He and 12C nuclei are calculated in energy higher than 1 GeV. The extracted results show good agreement with experimental data.
TL;DR: In this paper, the authors used nuclear emulsions for very high-energy nuclear reactions and showed that two distinctly different classes of relativistic projectile-like fragments are emitted in primary interactions: a "cool" channel with a temperature of (T(p)cool ≈ 10 MeV) and a "hot" Channel with (Tp)hot ≈ 40 MeV).
Abstract: An enhanced neutron production and an enhanced nuclear destruction due to secondary fragments have been observed in very thick targets irradiated with high energy ions. This enhancement is beyond theoretical calculations and it is an unresolved problem. It is observed only when primary ion interactions exceed an energy threshold (ECM/u ≈ 150 MeV). Investigations using nuclear emulsions for very high-energy nuclear reactions suggest that two distinctly different classes of relativistic projectile-like fragments are emitted in primary interactions: a “cool” channel with a temperature of (T(p)cool ≈ 10 MeV), and a “hot” channel with (T(p)hot ≈ 40 MeV. This second reaction class may induce the above mentioned enhanced reactions of secondary fragments, thus being responsible for unresolved problems. This assumption should be studied in further experiments. Nuclear interactions of secondary particles in thick targets are of interest, in particular in view of radiation protection needs for high energy and high intensity heavy ion accelerators. Many basic ideas of this paper go back to the late Professor E. Schopper (Frankfurt).
TL;DR: In this paper, a trace amount of uranium in drinking water samples collected from different locations of Faisalabadcity has been carried out using Neutron Induced Fission Track Technique.
Abstract: Drinking water plays a major role regarding quality of human life because polluted water is the main cause of many types of diseases. Besides other pollutants, high concentration of uranium above a certain level in drinking water is also hazardous. As water and food are the main sources of uranium intake, it is absolutely imperative that their level of concentrations is monitored regularly for safety of the general public. In this regard, trace amount of uranium in drinking water samples collected from different locations of Faisalabadcity has been carried out using Neutron Induced Fission Track Technique. The water samples along with the standard of known uranium concentration were poured and dried over Lexan track detectors and then irradiated with thermal neutrons in Reactor. After etching, the tracks produced in the detectors as a result of 235U (n, f) reaction were counted under an optical microscope. The uranium concentration was determined by counting and comparing the observed fission track density in the samples and the standard. The observed uranium concentration in the studied water samples varied from (1.04 ± 0.30) μg·L-1 to (21.08 ± 2. 95) μg·L-1 with an average value of (7.39 ± 1.30) μg·L-1 and is found to be within safe limits as far as uranium related health hazards are concerned.
TL;DR: In this article, a thermal conductivity of Zr + 30 vol% ZrO2 simulated inert matrix nuclear fuel pellet was evaluated using a hot-pressing method at 800°C in a vacuum and at a 20 MPa load.
Abstract: For an evaluation of a thermal conductivity of Zr + 30 vol% ZrO2 simulated inert matrix nuclear fuel pellet, a simulated fuel pellet was fabricated using a hot-pressing method at 800°C in a vacuum and at a 20 MPa load. And several thermophysical properties of the simulated inert matrix fuel pellet were measured and calculated. The thermal diffusivity and linear thermal expansion as a function of temperature of the simulated fuel pellet were measured using a laser flash method and a dilatometry, respectively. Finally, based on the experimental data, the thermal conductivity of the simulated inert matrix fuel pellet was calculated and evaluated.
TL;DR: In this article, the authors presented an application of calculation methods in neutron activation analysis (NAA) of a large crude oil sample and developed Monte-Carlo computer code to calculate neutron cross sections and neutron flux density distribution in the interior large sample.
Abstract: This manuscript presents an application of calculation methods in neutron activation analysis (NAA) of a large crude oil sample. Monte-Carlo computer code was developed. The computer code calculates neutron cross sections and neutron flux density distribution in the interior large sample. ENDF/B-VII.0 data files and ENSDF BNL-NCS-51655-01/02-Rev data files were used as nuclear databases in our computer code. HPGe planar detector efficiency registration technique and the software were developed for the absolute NAA technique of the large sample. The concentrations of Na, K, Ca, Sc, Cr, Fe, Co, Ni, Cu, Zn, Ga, As, Br, Sr, Zr, Mo, Ag, Sb, Cs, Ba, Ce, Nd, Sm, Eu, Tb, Dy, Ho, Tm, Yb, Lu, Hf, Ta, W, Pt, Au, Hg, Th and U in the crude oil samples of Eastern Siberia oilfield were determined using calculation and relative techniques in the concentration range from 10-9 to 0.5%.
TL;DR: Data analysis found that Br, Sc, Sm and Ti concentrations show a normal distribution, and there is no significant difference between street children and control group, but in the street children’s hair, the levels of Au, U, V are decreased and the Levels of Co, La, Sb, Th are increased compared to the control group.
Abstract: This study aimed to assess trace element concentrations in the hair of street children. Nutritional status was assessed by 24 hours’ dietary recall and anthropometric measurements. Data analysis found that Br, Sc, Sm and Ti concentrations show a normal distribution, and there is no significant difference between street children and control group. However, in the street children’s hair, the levels of Au, U, V are decreased and the levels of Co, La, Sb, Th are increased compared to the control group.
TL;DR: The radioisotopes are those continuously produced by nuclear reactions among light elements present in earthly atmosphere and radiations coming from the outside space as mentioned in this paper, and they were created at the same time that the nonradioactive isotopes composing the 92 natural elements in the periodic table.
Abstract: When Periodic Chart of elements is consulted to find natural radioisotopes, one firstly finds tritium, followed by 10Be, 14C, 50V and many others. Before Bi, 12 cosmogenic radioisotopes are listed. They are those continuously produced by nuclear reactions among light elements present in earthly atmosphere and radiations coming from the outside space. Eighteen additional primordial radioisotopes are listed. They were created at the same time that the non-radioactive isotopes composing the 92 natural elements in the periodic table. From Bi on, every isotope is radioactive, up to U. Then follow the artificial elements produced by laboratory nuclear reactions from Np to element with atomic number 118. In this way, from 118 known elements, 64 are radioactive, which amount 55% of all those units forming the chemical compounds. Therefore, the complete understanding of radioactivity should be a suitable tool to advance our knowledge of Universe, and consequent applications to get better living conditions. So, this paper deals with radioisotopes as suitable instruments for chemical analysis.
TL;DR: In this paper, data analysis and modeling of gamma ray tomography taken into account spatial resolution and source of errors and the attenuation coefficient measurement in row data from tomography process are presented.
Abstract: In this paper, data analysis and modeling of gamma ray tomography taken into account spatial resolution and source of errors and the attenuation coefficient measurement in row data from tomography process are presented. The results showed that this method is simple, effective and should be prior to any data treatment for opaque vessel reactor and by reconstruction algorithm in process imaging.
TL;DR: In this article, the binding energies of hydrogen and helium isotopes were analyzed with analytical formulas and the precision varies between 1 and 30 percent without fitting, adjustment, correction or estimation, proving the electromagnetic nature of nuclear energy.
Abstract: The one million times ratio between nuclear and chemical energies is generally attributed to a mysterious strong force, still unknown after one century of nuclear physics. It is now time to reconsider from the beginning the assumptions used, mainly the uncharged neutron and the orbital motion of the nucleons. Except for the long range Coulomb repulsion, the electric and magnetic Coulomb’s forces between adjoining nucleons are generally assumed to be negligible in the atomic nucleus by the nuclear specialists. The Schrodinger equation with a centrifugal force as in the Bohr model of the atom is unable to predict the binding energy of a nucleus. In contrast, the attractive electric and repulsive magnetic Coulomb forces alone explain quantitatively the binding energies of hydrogen and helium isotopes. For the first time, with analytical formulas, the precision varies between 1 and 30 percent without fitting, adjustment, correction or estimation, proving the electromagnetic nature of the nuclear energy.
TL;DR: In this paper, the operating principles of the two duoplasmatron ion sources and the PIG source available for the Van de Graaff accelerator have been determined qualitatively, mainly by studying the extensive literature on ion sources.
Abstract: The operating principles of the two duoplasmatron ion sources and the PIG source available for the Van de Graaff accelerator have been determined qualitatively, mainly by studying the extensive literature on ion sources. The main characteristics of the three sources have therefore been determined experimentally on an ion source test bench. Important parameters of the sources such as the pressure and temperature in different regions of the sources not measured, because of space limitations. However, in spite of these limitations in quantitative understanding of the sources, sufficient information to continue with the study of the beam transport through the Van de Graaff accelerator and its beamlines could be obtained from these measurements. With regard to beam intensity, lifetime and gas consumption the measurements showed that the hotcathode duoplasmatron is at present by far the most suitable source for the van de Graaff accelerator. The emittance of the ion source was measured with two slits, 90 mm apart, and a Faraday cup in the ion source test bench at an arc voltage of 83 V, an arc current of 1 Amp, a filament voltage of 24 V and an extraction voltage of 5 kV. The measured emittance for 90% of the beam intensity is 48π mm mrad. This figure will be used to calculate the beam transmission through the Van de Graaf accelerator. Different computer programs have been used for these calculations from the ion source through the terminal section, the accelerator and beam line up to the Nuclear Microprobe (NMP) for beam quality.
TL;DR: It is explored that SAM (Square Average Method), which was suggested as a method for reliability analysis in the previous study, is found to be suitable for the determination whether the measured thickness is acceptable or not and safety factors are proposed herein through the statistical analysis taking into account the components’ type.
Abstract: There are several thousand piping components in a nuclear power plant. These components are affected by degradation mechanisms such as FAC (Flow-Accelerated Corrosion), cavitation, flashing, and LDI (Liquid Droplet Impingement). Therefore, nuclear power plants implement inspection programs to detect and control damages caused by such mechanisms. UT (Ultrasonic Test), one of the non-destructive tests, is the most commonly used method for inspecting the integrity of piping components. According to the management plan, several hundred components, being composed of as many as 100 to 300 inspection data points, are inspected during every RFO (Re-Fueling Outage). To acquire UT data of components, a large amount of expense is incurred. It is, however, difficult to find a proper method capable of verifying the reliability of UT data prior to the wear rate evaluation. This study describes the review of UT evaluation process and the influence of UT measurement error. It is explored that SAM (Square Average Method), which was suggested as a method for reliability analysis in the previous study, is found to be suitable for the determination whether the measured thickness is acceptable or not. And, safety factors are proposed herein through the statistical analysis taking into account the components’ type.
TL;DR: In this article, an overview of biomedical projects performed at iThemba LABS, particularly in relation to the spatial distribution of trace metals in hard human tissues from disadvantaged Sudanese communities, such as kidney stone concretions, teeth and hair, undertaken at the NMP facility.
Abstract: This study deals with an overview of the biomedical projects performed at iThemba LABS, particularly in relation to the spatial distribution of trace metals in hard human tissues from disadvantaged Sudanese communities, such as kidney stone concretions, teeth and hair, undertaken at the iThemba LABS Nuclear Microprobe (NMP) facility. Relevant information about the ion beam techniques used for material characterization was discussed. The Particle Induced X-ray Emission (PIXE) technique was used to investigate the elemental composition of human hard tissues on a microscopic scale with the elemental mapping; complementary ion beam techniques are used to provide information on the major and minor components. Analysis of teeth sections by μ-PIXE showed that the levels of trace elements were enriched and/or depleted, this may associated with leaching and/or erosive processes. On the other hand the characterization of kidney stone concretions by μ-PIXE showed a marked difference of individuals from different region within Sudan.