Es-Salam Research Reactor Research Articles

Performance evaluation of the laboratory applying k0-NAA at Es-Salam research reactor during 2021–2022

Performance evaluation of the laboratory applying k0-NAA at Es-Salam research reactor during 2021–2022

Production of 192Ir sealed sources in Es Salam research reactor for non-destructive testing

Abstract An iridium-192 miniature sealed source was produced by irradiation of 12 metal disks of natural iridium (470.5 mg) under a thermal neutron flux of 9.4 × 1013 n cm−2 s−1 during 200 h in Es Salam research reactor (Algeria). The preliminary activity was measured after 10 days decay time by a CAPINTEC type CRC-712 M dose calibrator, the given activity was 1.9 × 1011 Bq (5.2 Ci). To estimate source activity, a modeling of reactor core and irradiation container with the targets was made by MCNP5 code with and without iridium targets to evaluate the effect of the disturbance and reaction; the calculated activity using disturbed flux was comparable with that measured. A non-destructive test using 192Ir sealed sources with GammaMat TSI type B(U) projectors was carried out to evaluate the integrity of the weld joint at the bend of a carbon steel pipe. The weld quality of two plates; carbon steel and stainless steel was also evaluated. In terms of sensitivity, the resulting gamma images matched well and reported a real finding on the state of tested samples.

FPGA-based real-time implementation of a digital reactivity-meter

The aim of this paper is to present a Hardware/Software design approach for the real-time implementation of a digital reactivity meter on a Zynq SoC platform (FPGA: Field-Programmable Gate Array). As a primary design tool, the Xilinx System Generator (XSG) programming tool has been used. The elementary hardware digital processing units, used to solve the inverse kinetics equations, have been implemented inside the Programming Logic (PL) part of the Zynq platform. Other secondary tasks, such as communication with the host PC, data storage and display have been devoted to the software application running on the Processing System (PS) part. A dedicated Graphical User Interface (GUI) has been also developed on a remote host computer. This application will be essentially used to handle the communication with the embedded reactivity measurement system and to display the reactivity evolution curves through the time. The design has been validated by comparing the obtained results with those proposed in the literature. Real plant data, acquired from Es-salam research reactor, has been also used to confirm the online efficiency of the design. Experimental results demonstrate that the system works well for both negative and positive reactivity insertions.

Experimental determination and simulation of neutron and gamma flux parameters in horizontal channel for Prompt Gamma Neutron activation analysis implementation at Es-Salam research reactor

Since 2004, the k0-standardization method has been applied and evaluated in three experimental channels at Es-Salam research reactor of the Algerian Centre de Recherche Nucléaire de Birine (CRNB). The NAA laboratory at CRNB is well involved in the implementation of the Prompt Gamma Neutron Activation Analysis to extend the field of analyses to some additional elements to the NAA method. In the frame work of the PGNAA research project, several works have been carried out in the present study including the experimental and simulation characterization of neutron and gamma flux parameters of the horizontal channel. The absolute and relative neutron fluxes of the studied channel have been determined by using a set of monitors including Al, Au, Cu, Fe and Zr. Furthermore, measurements of gamma and thermal neutron doses have been achieved using LiF: Mg, Ti (TLD 600 and TLD 700) detectors. The gamma dose rate at the experimental channel center position was found to be 0.6 Gy/min·MW. The experimental results obtained in this study have been used as input information for simulations and design of neutron facilities and radiation shielding, which are successfully established by SCALE code. The results were compared in terms of spectral detail and precision and a good agreement has been revealed. The value of the thermal neutron flux was found to be (6.29 ± 0.25) E+08 n/cm2.s which allows the implementation of PGNAA at the Es-Salam research reactor.

Pellet-cladding mechanical interaction analysis of heavy water fuel rods under power ramps

A numerical simulation is used to analyze the pellet-cladding mechanical interaction (PCMI) of a heavy water research reactor (RR) fuel rods under power ramps. A mechanical simulation that best reproduces the thermomechanical behavior of the pellet-cladding system is a major industrial challenge for engineers because it involves defining operating rules that are not too restrictive but that guarantee safety requirements. The majority of currently existing codes for processing thermomechanical behavior, under irradiation, of the PCMI evolution are designed for light water reactors. This is justified by the fact that most of the world nuclear power reactor park is composed of light water reactors. However, many nuclear reactors use heavy water as coolant, e.g. type CANDU reactors. In addition to the coolant thermodynamics table which is different for the two types of codes, the conditions of use in terms of pressure and temperature in the case of RRs are less severe than those in the case of nuclear power reactors (NPRs). In this study, we used several computer codes namely MCNP5, RODBURN, FEMAXI-6, and an analytical application, developed locally, to simulate the thermomechanical behavior of the Es-Salam RR fuel rods. The fission product cross-section library that was used with the RODBURN code was produced by using the ORIGEN code fed with the neutron flux spectrum of the Es-Salam research reactor. A new approach has been developed for the PCMI analysis of a heavy water reactor by using a code originally developed for light water reactors. Operating limits have been determined when the two tables of thermodynamics of coolants are different.

Vibration analysis of an irradiation device prototype for NTD-Si for the Es-Salam research reactor

Vibration analysis of an irradiation device prototype for NTD-Si for the Es-Salam research reactor

Vibration analysis of an irradiation device prototype for NTD-Si for the Es-Salam research reactor

Vibration analysis of an irradiation device prototype for NTD-Si for the Es-Salam research reactor

Conceptual design of irradiation device for silicon neutron transmutation doping around Es-Salam research reactor

Silicon neutron transmutation doping remains one of the most viable nuclear applications for research reactors. Providing this kind of product involves an irradiation method capable of fulfilling the quality requirements of doping and alleviating the challenges related to the design and safety of the irradiation device. In this paper, we propose an irradiation device prototype for neutron transmutation doping of silicon ingots with diameters of 2 to 3 in. based on the Es-Salam research reactor. The thermal hydraulic analysis of the proposed irradiation device was performed to determine the optimum conditions for cooling. The effect of the mechanical vibrations induced by the circulation of coolant in the device was quantified via experimental measurements under different flow rates. The results show that the maximum temperature reached by the silicon ingots is below the temperature limit, effectively validating the design of the irradiation device. Other investigations are prospected to further optimize the design and the irradiation conditions. The irradiation of silicon ingots with a large diameter will be considered.

Calculation of SIFs for semi-elliptical surface cracks in U-shaped bellows expansion joints of Es-Salam research reactor vessel

Expansion joint (EJ) of Es-Salam research reactor (RR) vessel as an element for deformation compensating is subjected to the axial load due to thermal expansion and often work under hostile environment (corrosion, radioactivity, etc.). As some local regions with high elastoplastic strain of bellows type EJ undergo cyclic loadings caused by startup and shutdown and changeable operating conditions of RR, they can be ruptured by crack growth. Therefore, it is necessary to evaluate the influence of cracks to structural integrity of EJ of Es-Salam RR vessel. The fracture criterions as stress intensity factor (SIF) or J-integral (JI) are used to evaluate the resistance to fracture of the constructions with cracks. The SIF is a parameter, which is used to estimate a material resistance to brittle fracture.In the present study the problem of calculation of the SIF of semi-elliptical crack (SEC) located in the stress concentration areas of EJ installed between the lower barrel and the upper barrel of a RR pressure vessel is numerically solved by advanced global-local finite element (FE) analysis. The crack locations are considered at the intersection of the various parts that construct the EJ. The modeling details and methodology, employed in the analysis, are extensively discussed and the numerical approach is proven to be efficient for the SIFs calculation of EJ semi-elliptical cracks. The proposed methodology using software ANSYS was validated by applying the analytical methods (according ASME requirement and R6 method) and also a finite element method but using software ABAQUS. It was received that SIF data are in close agreement. It was demonstrated that applied methodology for modeling of the SIF can be used.

Numerical simulation of SIF in Es-Salam research reactor vessel

Abstract During NPP operation the reactor vessel will be affected by degradation mechanizms, such as thermal aging, irradiation embrittlement, corrosion and fatigue. These degradation mechanisms may significantly impact component integrity. When the metal is aging under certain conditions, the crack can appear and this finally could lead to the failure of components. The stress intensity factor (SIF) as fracture criterion are used to evaluate the resistance to fracture of the components with cracks. In the case of complex structures the estimation of stress intensity factor it is complicated by applying only the analytical formulas. The Es-Salam research reactor vessel is a complex 3D structure with high level safety requirements. As a result, sophisticated methods are necessary for the fracture analysis of critical components. In this manuscript the proposed methodology for the numerical simulation of the stress intensity factor in Es-Salam research reactor vessel by finite element method using software ANSYS is presented. The validation of the proposed methodology was performed by analytical analysis (according ASME requirement and R6 method (SACC software)). Additionally this methodology was validated by applying a finite element method using software ABAQUS. The comparison of these results shows a good coincidence, and the deviation does not exceed 9%. According to this, the proposed methodology can be used for numerical simulation of the stress intensity factor in Es-Salam research reactor vessel.

Measurement of selenium in two Algerian chenopods (Atriplex canescens (Pursh.) Nutt. and Suaeda fruticosa (Linn.) Forssk)

Neutron activation analysis laboratory (NAA measurement) was applied for the determination of selenium (Se) contents in two perennial forage species (Atriplex canescens (Pursh.) Nutt. and Suaeda fruticosa (Linn.) Forssk) used in extensive livestock production systems, in arid rangelands of Algeria. Se content was estimated in leaves and in the soil in which the plants were grown. The vegetal and soil samples were irradiated for 6 h duration with a thermal neutron flux of 4.5 × 1013 cm−2 s−1 of Es-Salam research reactor (Berine, Algeria). The daily intake of Se was determined and compared with the values recommended by National Research Council (NRC) guidelines. Result showed that the highest contents of Se were found in the rainy period (January–15 winter) for both species. By way of contrast, for the surrounding soil this metalloid was higher during dry season (July–15 summer). The maximum uptake of Se was predominantly recorded in A. canescens (0.16 ± 0.07 μg g−1) compared to S. fruticosa (0.07 ± 0.03 μg g−1). The bioaccumulation factor (BFSe) from soil to plant showed a high enrichment of Se especially for A. canescens. In conclusion, this study envisages that A. canescens can be gazed by livestock in winter season as a source of Se; however the problem of Se deficiency was expected during the other seasons for animals grazing A. canescens and S. fruticosa.

Application of INAA technique for analysis of essential trace and toxic elements in medicinal seeds of Carum carvi L. &Foeniculum vul-gare Mill. used in Algeria

Traditional medicinal seeds such as caraway “Carum carvi L.” and Foeniculum vulgare Mill. commonly called fennel have been largely used since several centuries for a wide range of ailments related to digestive, endocrine, reproductive, and respiratory systems. Additionally, it is also used as a galactagogue agent for lactating mothers. The Algerian neutron activation analysis laboratory is highly involved in nutrition applications in the framework of research activities using the Es-Salam research reactor. The objective of this work is to contribute by using nuclear analytical techniques, for studying a large number of natural food samples consumed in Algeria related to nutrition and human health. The present study focuses on the analysis of the seeds of caraway and fennel used in our country by using instrumental neutron activation analysis (INAA) technique. Twenty-seven elements were assessed (As, Ce, Co, Cr, Cs, Eu, Hf, La, Mo, Lu, Nd, Sb, Sc, Se, Sm, Tb, Yb, Th, Ba, Br, Rb, Sr, Zn, Ca, K, Na and Fe) and the accuracy of the method was evaluated by analyzing the Certified Reference Materials (CRMs). The daily intake of essential and toxic elements was determined and compared with the recommended values and was found to be well below the tolerance limits.

Neutron activation analysis of major and trace elements in Arabica and Robusta coffee beans samples consumed in Algeria

Abstract The Algerian neutron activation analysis laboratory is highly involved in nutrition applications in the framework of research activities using the Es-Salam research reactor. The main objective of this work is to contribute, by using nuclear analytical techniques, for studying a large number of natural food samples consumed in Algeria related to nutrition and human health. The present study focuses on the analysis of the most popular beans consumed worldwide, namely, the coffee species of Arabica and Robusta, based on the international markets. Chemical content of samples was assessed by instrumental neutron activation analysis (INAA) and k 0-INAA techniques, through the irradiation of samples during 6 h at a thermal neutron flux of 4.5×1013cm−2s−1 of Es-Salam research reactor. A total of 17 elements were assessed such as, (Br, Ca, Ce, Co, Cr, Cs, Fe, K, La, Na, Rb, Sc, Sm, Sr, Zn, Lu and Th) obtained by using INAA and k 0-INAA methods, While we used the radiochemical neutron activation analysis (RNAA and k 0-RNAA) to determine Selenium at low level concentrations, the accuracy of the method was evaluated by analyzing CRM and SRM. QC/QA was evaluated by using the statistical parameter U-score. Results were compared with those obtained for samples from Brazilian, Caribbean, Indian and Kenyan coffee beans reported in the literature. The daily intake of essentials and toxic elements was determined and compared with the recommended values. The probable cumulative intake of toxic elements was found to be well below the tolerance limits.

Displacement damage cross section and mechanical properties calculation of an Es-Salam research reactor aluminum vessel

Nuclear facility aging is one of the biggest problems encountered in nuclear engineering. Radiation damage is among one of the aging causes. This kind of damage is an important factor of mechanical properties deterioration. The interest of this study is on the Es-Salam research reactor aluminum vessel aging due to neutron radiation. Monte Carlo (MC) simulations were performed by MCNP6 and SRIM codes to estimate the defects created by neutrons in the vessel. MC simulations by MCNP6 have been performed to determine the distribution of neutron fluence and primary knock-on atom (PKA) creation. Considering our boundary conditions of the calculations, the helium and hydrogen gas production in the model at a normalized total neutron flux of 6.62 × 1012 n/cm2 s were determined to be 2.86 × 108 and 1.33 × 109 atoms/cm3 s, respectively. The SRIM code was used for the simulation of defects creation (vacancies, voids) in the aluminum alloy of the Es-Salam vessel (EsAl) by helium and hydrogen with an approximate energy of 11 MeV each. The coupling between the two codes is based upon post-processing of the particle track (PTRAC) output file generated by the MCNP6. A small program based on the MatLab language is performed to condition the output file MCNP6 in the format of a SRIM input file. The concentration of silicon was determined for the vessel by the calculation of the total rate of 27Al(n,γ)28Si reaction. The DPA (displacement per atom) was calculated in SRIM according to R.E. Stoller recommendations; the calculated value is 0.02 at a fast neutron fluence 1.89 × 1019 n/cm2. RCC-MRx standard for 6061-T6 aluminum was used for the simulation of the evolution of mechanical properties for high fluence. The calculated values of nuclear parameters and DPA obtained were in agreement with the experimental results from the Oak Ridge High Flux Isotope Reactor (HFIR) reported by Farrell and coworkers.

Determination of Na, K, Fe, and Zn whole blood elements concentration of Algerian Alzheimer patients by k 0-NAA method

k0-Standardization method was applied in clinical investigation to evaluate the whole blood correlation factor of Na and K, Fe and Zn of 21 patients suffering from Alzheimer pathology and 5 normal controls. Samples were irradiated at Es-Salam research reactor. However, the concept (QC/QA) is considered to evaluate the accuracy of the method. NIST 1566b (Oyster tissue) and IAEA A13 (animal blood) were analyzed simultaneously with the samples. Three statistical parameters Z-score, U-score and bias were determined and discussed.

Sequential extraction of Cs and Sr from Ain Oussera soils around Es-Salam research reactor facility

Four types of undisturbed soil in Ain Oussera region around the Es-Salam reactor facility, located in the south of Algiers, Algeria, at about 200km, were artificially contaminated for one year with stable CsCl and SrCl2 in order to simulate an accidental release of these elements. This study was performed using sequential extraction procedure based on Shultz method and containing six fractions. The selectivity of the extraction protocol was confirmed by analyzing some elements (Ca, C, Fe, Mn, Si and Al) designed as indicators of the targeted phases. The obtained results showed an acceptable reproducibility, in view of the coefficients of variation that were in most cases less than 15%. The results revealed a clear proportional correlation between the extracted Cs and Sr in fractions for each soil and some of soils physicochemical properties. Organic matter appears to play an important role in the soil retention, particularly for Cs where the extracted percentage exceeds to 30% in whole soils. In contrast, strontium expresses a remarkable affinity for the fraction bound to carbonates. The obtained data also indicate that the availability of Cs in the four soils is less important compared to Sr availability. This is illustrated by the higher value of extracted Sr in the easily extractible phase, including the water-soluble and the exchangeable fraction.

Major, minor and trace elements in four kinds of cement powder using INAA and k 0-standardization methods

In this work, we aim to get the concentration of major, minor and trace elements in four kinds of cements powder using INAA and k0-NAA methods. All samples were irradiated at Es-Salam research reactor with a thermal neutron flux of 3.76 1013 n/cm2 s. In this study, the concentration values of 32 elements were determined using both techniques. The comparison was carried out by the mean of ratios between experimental results obtained by k0-NAA and INAA of four cement samples. Certified reference materials NIST1646a and GSD12, respectively, were used to check reliability of the methods.

Application of CR-39™ SSNTD with a boron converter for the characterization of the external neutron beam of a powder diffractometer

In this work, the solid state nuclear track detector (SSNTD) CR-39™ has been used in combination with a boron converter screen for the characterization of the neutron distribution in the neutron powder diffractometer of the Es-Salam research reactor. A relationship between the track density in the CR-39™ and the neutron flux distribution has been established by a mathematical development. Good agreement was found between the distribution of the thermal neutron flux determined by CR-39™ detector and the distribution measured by the activation of Dysprosium foils. On the other hand, the degree of homogeneity of the neutron beam has been determined by the SSNTD and direct neutron radiography techniques. The results obtained by both techniques showed a depression of the flux at the left bottom region of the beam.

Trace and essential elements determination in baby formulas milk by INAA and k 0-INAA techniques

As a part of the food analysis program executed at Es-Salam research reactor by neutron activation analysis laboratory, the concentration of As, Ba, Br, Ca, Fe, K, La, Rb and Zn in baby formulas milk have been determined by using INAA and k0-NAA techniques. It was found that the concentration of all elements obtained by both techniques was relatively identical for the three brands of the 0–6 and 6–12 months of analyzed samples. In addition, the analytical results have been compared with those given by producers.

NAA Algerian Laboratory Evaluation Processed by WEPAL and IAEA during 2011-2012

Participation in inter-comparison programs is an important process to enhance the accuracy and precision of the analytical techniques used in the laboratories. At Es-Salam Research Reactor, our laboratory uses two functional analytical techniques such as INAA and k0-INAA in the research projects and for the completion of the service works. Recently, our laboratory has participated in two inter-comparison tests organized by IAEA within the framework of the AFRA project to assess the analytical performance of eighteen (18) African analytical laboratories participating in the RAF/4/ 022 project, Enhancement of Research Reactor Utilization and Safety by taking part in analytical proficiency testing IAEA in conjunction with WEPAL, the Wageningen Evaluating Programs for Analytical Laboratories. The Proficiency Testing tests related to the determination of major, minor and trace elements in materials of the International Soil and Plant Analytical Exchange (Wepal codes ISE, IPE), were held in the fourth quarter of 2011 and the first quarter of 2012, respectively. Concentrations of thirty (30) elements such as Al, As, Ba, Br, Ca, Cd, Ce, Co, Cr, Cs, Fe, Ga, K, La, Mg, Mo, Mn, Na, Nd, Rb, Sb, Sc, Sr, Th, Ti, U, V, W, Zn, Zr were determined in ISE and IPE samples. All results were evaluated and reported in this paper.