Atomic Energy Research Institute Research Articles

Establishment of Hp(3) calibration system for eye dose monitoring in Taiwan.

In response to the ICRP's amending the occupational exposure limit for the eye lens, the Institute of Nuclear Energy Research (INER) established the Hp(3) calibration system for eye dose monitoring in Taiwan to accurately assess the dose received in the eye lens. INER employed the narrow-spectrum series radiation according to the ISO 4037 as the X-ray radiation qualities, and the measured half-value layer consistent with a 5% difference. The air kerma rate standard was determined by the self-made free air chamber, and through dose conversion coefficient referring to ISO 4037 to obtain the Hp(3) on an ISO cylinder phantom. Furthermore, the calibration system was provided as the characteristics tests for DOSIRIS headset dosemeters. Finally, the Hp(3) calibration system has been established in Taiwan, and it can be used to provide calibration services for eye lens dosemeters and be applied to the proficiency testing that will be held in 2023.

Coleopteran Diversity at the three selected areas in Dhaka City, Bangladesh

The diversity of coleopteran species was studied at three different selected areas in Dhaka city from December 2016 to November 2017. A total of 11,397 individuals of 56 coleopteran species belonging to 50 genera, including 15 families, were recorded in the study areas during the study period. Of them, 47 species (4916 individuals) of 13 families were found at the Ramna Park, 48 species (2441 individuals) of 15 families at the National Botanical Garden, and 42 species (4040 individuals) of 11 families at the Atomic Energy Research Establishment (AERE) campus. A total of 30 species, 25 genera, and 11 families were common in these three study areas. At the Ramna Park, the highest species richness included the family Chrysomelidae (34.04%), and the lowest was under the six families including Staphylinidae, Bostrichidae, Nitidulidae, Geotrupidae, Erotylidae, and Scarabaeidae (2.13%). At the National Botanical Garden, the maximum number of species was recorded under the family Chrysomelidae (6.24%), and the lowest was under seven families including Staphylinidae, Bostrichidae, Nitidulidae, Geotrupidae, Erotylidae, Elateridae, and Dermestidae (2.08%). The maximum number of coleopteran species was identified under the family Chrysomelidae (35.71%), and the lowest was under six families including Staphylinidae, Cerambycidae, Nitidulidae, Geotrupidae, Elateridae, and Dermestidae (2.38%) at the AERE campus. The Shanon’s Diversity Index (H′) and Simpson’s Index (λ) indicate high coleopteran diversity at the Ramna Park (H′=3.41, λ=0.05), the AERE Campus (H′=3.07, λ=0.06), and the National Botanical Garden (H′=2.93, λ=0.08). The high species evenness in the Ramna Park (J’= 0.89) and the AERE campus (J’= 0.82) indicates that the species were evenly distributed, whereas at the National Botanical Garden (J’= 0.76) they were comparatively less evenly distributed. The calculated Sorenson’s Coefficient (CC) is 0.66, indicating that these three communities were fairly similar or overlapped. The Community Dominances were 21.03%, 32.16% and 18.66% for the Ramna Park, National Botanical Garden, and AERE campus, respectively. Bangladesh J. Zool. 50 (2): 185-200, 2022

Radiation protection evaluation and spontaneous discharge performance of betavoltaic tritium batteries using well-aligned titanium dioxide nanotube arrays

Nuclear power plants produce the largest amount of tritium. Tritium is a by-product of nuclear reactors. Currently, it can only be placed in sealed storage tanks. Radioactive waste can be used as a source of energy for radioisotope battery. Since isotope energy is continuously converted into electrical energy for a long period of time, it is considered an ideal choice for remote applications. The mechanism of current generation of nuclear batteries is similar to that of solar cells. The only difference is that the electron holes are generated from radiation, not from light. The novel technologies of betavoltaic batteries would make use of the synthetic strategy for TiO2 semiconductors and the radioactive wastes radiation sources (H-3) stored in INER (Institute of Nuclear Energy Research, Taiwan). The radioactive waste can become a source of energy for radioisotope generators. At first, this study evaluates the radiation shielding safety distance required for radioactivity used in a betavoltaic tritium battery. The technological innovation includes the experimental synthesis of TiO2 nanotube in a complete array and the use of TiO2 nanotube arrays (TNTAs) as the semiconductor inside radioisotope batteries. In this work, combining the technology of TiO2 synthesizing TiO2 nanotube arrays with liquid waste radiation sources (tritium, H-3), the betavoltaic tritium battery (Ni/H-3/TNTAs/Ti) have successfully created and analyzing the characteristics of betavoltaic battery. Durability was assessed using analytical parameters of betavoltaic batteries compared to lithium-ion batteries. Such betavoltaic batteries have practical advantages in tritium handling applications and long-term battery performance.

The interface design of storage and examination system for BWR spent nuclear fuel dry storage demonstration project in Taiwan

Due to the lack of Boiling Water Reactor (BWR) fuel examination data after dry storage, Taiwan Power Company and Institute of Nuclear Energy Research jointly launched the “Taiwan Nuclear Fuel Storage Demonstration Project” to collect fuel characteristics data under simulated dry storage. To meet the project requirements, BWR fuel rods in different fuel designs will be selected and then store in simulated storage containers in different environments for 10 years. The interface considerations and design results of the auxiliary equipment for spent nuclear fuel storage, transfer, and non-destructive testing in the simulation stage of spent fuel dry storage were summarized. In addition, the possibility of operating at high heating power and avoiding deformation of the components due to thermal extension of the storage containers after heating was included in the design consideration. A simplification concept was introduced, with frequent NDT (Non-destructive Testing) inspections that will be performed through the spent fuel transfer process. The test results showed that the interface design can meet the requirements of long-term experiment, maintenance and radiation protection requirements, and is ready for further demonstration.

The preparation of segmenting the TRR reactor vessel internals with higher radiation

Based on the approved Taiwan Research Reactor (TRR) Decommissioning Plan, TRR decommissioning task must be finished before March 2029, and the reactor vessel should be fully dismantled before the end of 2028. However, Taiwan has no experience on dismantling a nuclear reactor vessel and lacks the associated containers and equipments, especially those used for handling the internals with higher radiation. To reach the goal of dismantling TRR reactor vessel in time, Institute of Nuclear Energy Research (INER) has made the dismantling strategy and developed the associated containers and equipments. Concerning the personnel safety, these internals with higher radiation will be segmented under the water. This makes the equipments and container used for segmenting these internals and storing the segmented parts are hard to be accessed from the commercial market directly and need to be developed in advance. To cope with these challenges, INER has designed the underwater disc saw and band saw equipments to segment these internals and developed INER-LRW-C2 low level radioactive waste container to store and transport those segmented parts. Currently, these equipments used for segmenting these internals are under mockup tests, and INER-LRW-C2 low level radioactive waste container has been granted the usage permit.The content of this article briefly introduces how INER prepares to face these challenges and what it has done. This includes the TRR reactor vessel dismantling strategy and segmentation plan of these internals with higher radiation, the development of INER-LRW-C2 low level radioactive waste container, and the designs of these major associated segmentation equipments.

Physicochemical and microbiological evaluation of surface water quality of aquaculture ponds Located in Savar, Dhaka, Bangladesh

Aquaculture is one of the most vital sectors in Bangladesh as it exhibits a major role in nutrition, livelihoods and foreign exchange incomes/earnings every year. However, due to chemical impurities, infectious diseases caused by microorganisms, heavy metal accumulation, and aquaculture in Bangladesh is gradually declining and posing serious health risks. In Savar, which is one of the major industrial zones in Bangladesh, all industrial sewage and wastes severely deteriorate the water quality of the ponds, rivers, lakes and various waterways that are involved in aquaculture/fish culture. Hence, to determine the water quality by assessing different physicochemical and microbiological parameters, water samples were collected from five selected ponds located in Atomic Energy Research Establishment premises, Savar, Dhaka and analyzed according to the standard procedures. The obtained values of temperature, pH, Salinity, TDS, TA, EC, TH, Chloride content, Free CO2, DO, Nitrate and Sulfate were compared with the recommended values of Bangladesh and WHO standard for suitable water quality. Most of the physicochemical parameters exceeded the Standard value. Total Viable Count, Total Coliform and Fecal Coliform Count were also found to be higher than the standard value of WHO indicating fecal contamination of the pond water. Some fish pathogens were also isolated from the ponds. Water quality index (WQI) was calculated for five sampling sites to determine the level of pollution. It was observed that the water quality of the all the ponds reached to critical point of pollution. It is therefore, a high time to take initiatives to save the ponds that are involved in aquaculture from further pollution. The results revealed that the pond waters of five different sites were excessively polluted and unsuitable for fish culture.

The storage container for demonstrate BWR spent nuclear fuel dry storage in Taiwan

Considering the unique operation of each nuclear power plant and lack of BWR fuel examination data after dry storage, the Taiwan Power Company and Institute of Nuclear Energy Research conduct the “The Nuclear Fuel Storage Demonstration Project in Taiwan” to collect the data of the fuel characteristics under dry storage. In this project, BWR fuel rods among different fuel designs and fuel venders will be loaded into a simulated storage cask for 10 years. Different temperatures and environments will be adopted, for simulated normal storage condition and acceleration experiments be performed. Non-destructed examinations will be executed prior to loading the fuel rods and periodically during storage. After 10 years, the fuel rods will be extracted and examined non-destructively and destructively. This paper summarized the methodology to demonstrate the adequacy of spent fuel dry storage, the design and fabrication of the simulated storage containers, the results of performance test and the project progress. Two containers will be used in the prospective experiments; one is for the normal storage condition. The other is for accelerated experiments and various storage conditions. After completion of this project, the collected data and research results will be compared with other international projects to provide the technical basis in Taiwan.

Joint Strength of a Braze Sealant with Metallic Interconnect in Solid Oxide Fuel Cell

To meet the quick start-up characteristics of metal-supported solid oxide fuel cell (MS-SOFC), brazing seals have been used in many MS-SOFC systems. During the cyclic operation of SOFC, thermal stresses are unavoidably generated due to temperature gradient and mismatch of coefficient of thermal expansion (CTE) between components. Excessive thermal stresses may damage the structural integrity of an SOFC stack, which in turn reduces the efficiency and lifetime of the SOFC. Therefore, it is essential to study the mechanical properties of the joint between braze sealants and metallic interconnects at room temperature (RT) and operating temperatures for developing a reliable MS-SOFC stack. The aim of this study is to investigate the mechanical strength of a braze sealant/metallic interconnect joint in SOFC. The braze sealant used is a silver-based alloy which is developed at the Institute of Nuclear Energy Research (INER) for MS-SOFC. The metallic interconnect used is a commercial ferrite stainless steel (Crofer 22 H). Two types of sandwich-like joint specimens are made to determine the shear and tensile joint strength at RT and 750 °C. Experimental results indicate that a bonding time of 30 min produces better joint strength at RT than 20 and 40 min, and it is thus selected as the bonding time for the specimens used in the subsequent tests. For tensile loading mode, the joint strength at RT and 750 °C is of 30.63 ± 3.2 MPa and 13.43 ± 0.99 MPa, respectively. For shear loading mode, the joint strength at RT and 750 °C is of 40.02 ± 2.88 MPa and 10.06 ± 0.36 MPa, respectively. Fractography analysis reveals that regardless of testing temperature, fracture of the tensile specimens occurs at the interface between the braze sealant and the Cr2O3 oxide layer and occasionally within the Cr2O3 oxide layer. When the testing temperature of the shear specimens is increased from RT to 750 °C, the location of rupture changes from the interface between the braze sealant and Crofer 22 H to the interface between the braze sealant and the Cr2O3 oxide layer.

Implementation of Local Area Network (LAN) and Build a Secure LAN System for Atomic Energy Research Establishment (AERE)

Implementation of Local Area Network (LAN) and Build a Secure LAN System for Atomic Energy Research Establishment (AERE)

Intercomparison of Conventional and QuickScan Dicentric Scoring for the Validation of Individual Biodosimetry Analysis in Taiwan

Purpose The dicentric chromosome assay (DCA), the gold standard for radiation biodosimetry, evaluates an individual absorbed radiation dose by the analysis of DNA damage in human lymphocytes. The conventional (C-DCA) and QuickScan (QS-DCA) scoring methods are sensitive for estimating radiation dose. The Biodosimetry Laboratory at Institute of Nuclear Energy Research (INER), Taiwan, participated in intercomparison exercises conducted by Health Canada (HC) in 2014, 2015 and 2018 to validate the laboratory’s accuracy and performance. Material and Methods Blood samples for the conventional dose response curve for Taiwan were irradiated with 0, 0.25, 0.5, 1, 2, 3, 4 and 5 Gy. Ten blind blood samples were provided by HC. Either or both of two methods of conventional (C) or QuickScan (QS) scoring could be chosen for the HC’s intercomparison. For C-DCA triage scoring, only cells with 46 centromeres were counted and each scorer recorded the number of dicentrics in the first 50 metaphases or stopped scoring when 30 dicentrics were reached. Scorers also recorded how much time it took to analyze 10, 20, and 50 cells. Subsequently, the data were entered into the Dose Estimate software (DoseEstimate_v5.1) and dose estimates were calculated. With QS-DCA scoring, a minimum of 50 metaphase cells (or 30 dicentrics) were scored in apparently complete metaphases without verification of exactly 46 centromeres. Results For the blinded blood samples irradiated at HC and shipped to INER, the mean absolute deviation (MAD) derived after scoring 50 cells for C-DCA and QS-DCA was <0.5 Gy for all three intercomparisons, meeting the criteria for acceptance. Conclusion The results indicated that the Biodosimetry Laboratory at INER can provide reliable dose estimates in the case of a large-scale radiation accident.

Anaerobic digestion of kitchen waste generated from Atomic Energy Research Establishment (AERE) cafeteria for lactic acid production

Due to accelerated economic growth and increased food production, per capita rate of waste generation is also increasing in Bangladesh. Being the ninth most populous and twelfth most densely populated country in the world, Bangladesh will face serious crisis in both food scarcity as well as food loss if food wastage problem is not addressed. At household level, 5.5 percent food is wasted on daily basis. Due to its large volume, the disposal of food waste will be a major problem. Production of Organic acid from kitchen waste via anaerobic digestion can eliminate both waste pollution problem and high cost production of organic acid. Such organic acid can be used in food and beverages, cosmetics, and detergent industries. The present study was undertaken to convert kitchen waste generated from cafeteria of Atomic Energy Research Establishment (AERE), Savar, Dhaka into lactic acid using natural microflora. The number of indigenous microflora in kitchen waste were found to be 1.25×107 cfu/mL and pH range of 5.0-6.0. The ratio of rice, meat and vegetables in the kitchen waste was found to be 3:1:1. Kitchen waste was found to contain approximately 19.03% protein, 3.2% fat and 1.5% ash. Anaerobic digestion was carried out in shake flasks at various initial pH (5.0, 6.0 and 7.0) and different temperature (30℃, 37℃ and 45℃) for 96 hours. Highest lactic acid from Kitchen waste was produced (24.00 g/L) at 24 h at initially adjusted pH-7.0. An attempt to recover Lactic acid from fermented broth was conducted using rotary evaporation at 100℃ and at (60-65) cm. Hg vac. The results indicated that, the volume of food waste can be greatly reduced and can be converted into value-added products such as lactic acid via anaerobic fermentation.&#x0D; Asian Australas. J. Biosci. Biotechnol. 2020, 5 (3), 88-99

Wind Resources Assessment and Development of Grid Connected Wind Farm—A Case Study

In the present study, the case study of micro-siting for the campus of the Institute of Nuclear Energy Research (INER) is conducted. Results from the effect of weather data suggest that for the wind turbine system higher than 20 m, the effect of nearby building and wake on electricity production would be less important. The effect of different weather data on the generated annual electricity production (AEP) is consistent for the wind turbine higher than 20 m. The difference between the calculated and real AEP of INER-150 kW wind turbine is only 1.1%, which is much better than some previous studies. The good agreement is mainly due to the higher height of the INER-150 kW (50 m), more stable coming wind and smaller impact of building on the performance of power production. Considering the proactivity on the installation for the site in INER campus, the finalized decision on the selection of wind turbine is 1 kW system. The power generation-related data are collected and processed for the fine tuning of model parameters in the future.

Inspection and radiation dose evaluation results for NORM-containing products in Taiwan

In 2018, “negative ion powder” mattress produced by a South Korean manufacturer producing a dose rate of > 1 mSv/year, was found to have monazite powder in it. In order to verify if other products advertised as containing “negative ion powder” were also hazardous, an investigation had been carried out by the Atomic Energy Council and Institute of Nuclear Energy Research in Taiwan. By the end of April 2019, 11 kinds and a total of 59 samples were inspected for radon content. The radiation doses for the samples were evaluated using Atomic Energy Council approval evaluation setup which was established according to the characteristics of the products. The highest concentration of 220Rn among the inspected mattresses was over 10 kBq/m3 and the evaluated annual dose was about 78.5 mSv. The linearity of the surface dose rate and the measured thoron gas concentration for the mattress samples was also discussed in this study.

Proficiency testing and dose comparison for external personnel dosimeters evaluation in Taiwan

This study investigated the series of proficiency testing held by the Institute of Nuclear Energy Research (INER) from 2010 to 2017 and the benchmark of one type of dose evaluation system for personnel dosimeters in Taiwan. Based on the latest American National Standard Institute/Health Physics Society (ANSI/HPS) N13.11–2009 (R2015) performance testing standard, the personnel dose equivalent, Hp(d) data of the proficiency testing programs were reanalyzed to research the dose assessment ability and the criteria update feasibility. The results showed that the tolerance level (L), absolute of bias (|B|) and standard deviation (S) for all categories of all the 8 laboratories and 4 types of dosimeter well met the latest ANSI/HPS N13.11 criteria. In addition, the measurements of the Hp(d) with LiF: Mg, Ti-based TLD personnel dosimeters were also demonstrated by comparing with the MCNP6 Monte Carlo code. The dose responses were satisfactory in M100, M150 X-ray and 137Cs (including the angle tests) beams produced by INER for radiation protection level application.

Editorial: Biographical Memoirs , Volume 68

Editorial: <i>Biographical Memoirs</i> , Volume 68

Anthony Milner Lane. 27 July 1928—9 February 2011

Tony Lane came from humble beginnings to become one of the world's leading theoretical nuclear physicists. His career in the Theoretical Physics Division at the Atomic Energy Research Establishment (AERE) at Harwell was characterized by his outstanding successes in explaining experimental nuclear data. He pioneered the understanding of the important nucleon capture reactions by introducing new mechanisms of direct and semi-direct capture and, together with colleagues, he greatly advanced knowledge of nuclear analogue states, and the role of isospin in nuclear physics. With R. G. Thomas, he wrote a comprehensive review of R-matrix theory, applied to analyse resonances in nuclear reactions, which became one of the most cited papers in physics. His book Nuclear theory gave a good account of the use of pairing force theory in nuclear physics, and its application to nuclear collective motion.

Establishment of diagnostic X-ray air kerma standard in Taiwan

Diagnostic X-ray air kerma standards were established at the Institute of Nuclear Energy Research (INER, Taiwan) in accordance with the recommendations of IEC 61267. The radiation qualities established by INER include IEC 61267 RQR (RQR 3-10), RQA (RQA 3-10) and RQT. Among them, RQR is used to simulate the energy spectrum generated from the X-ray machine, RQA is used to simulate the energy spectrum after passing through the human body, and RQT is used to simulate the energy spectrum in computed tomography (CT).A tungsten target X-ray machine, 99.9% pure aluminum and copper filters were used to build the IEC 61267 radiation qualities. A cylindrical free-air chamber (FAC) is used as the X-ray air kerma primary standard. The FAC correction factors, including air attenuation, window attenuation, ion recombination, photon-scattering, electron-loss and shadow-effect, were evaluated by experiments or Monte Carlo methods.The half value layers (HVL) of these radiation qualities were measured by FAC, and the HVL differences between INER and IEC 61267 are less than 3%. The uncertainty of measurement was evaluated according to ISO GUM, and the relative standard uncertainty of primary standard is 0.53% (k = 1). An ionization chamber (Exradin A5) was sent to PTB and calibrated with IEC 61267 RQR and RQA qualities. When comparing the calibration factors between PTB and INER, the differences are less than 1.25%.The air kerma standard of diagnostic X-ray has been established at INER, and it will provide dose calibration services in Taiwan to improve medical quality.

Validation of a Commercial ELISA Kit for Screening 3-amino-2-oxazolidinone, A Furazolidone Antibiotic Residue in Shrimp

Furazolidone, a banned nitrofuran antibiotic, is still illegally used in aquaculture and livestock husbandry. A commercial Enzyme-linked Immunosorbent Assay (ELISA) from Europroxima, The Netherlands is described, and validated for the screening of 3-amino-2-oxazolidinone (AOZ), metabolite of furazolidone antibiotic in the muscle of shrimp. Research works was conducted at Veterinary Drug Residue Analysis Laboratory, Institute of Food and Radiation Biology, Atomic Energy Research Establishment, Savar, Dhaka-1349, between July 2018 and December 2019. Validation was done in accordance with the European Commission (EC) decision 2002/657/EC in terms of specificity, detection capability CCβ, selectivity, ruggedness, and stability. Homogenized sample was subjected to acid hydrolysis for releasing of tissue bound metabolite AOZ, and derivatized with o-nitrobenzaldehyde followed by ethyl acetate/n-hexane extraction and detection by ELISA reader. The detection capability CCβ of the method was lower or at 0.3 µg/kg accepting 0% false compliant result. Cut-off factor Fm and the positivity threshold value T was 0.716 and 0.982, respectively. Mean OD of blank sample B was1.225. The assay was valid because T was greater than Fm and smaller than B. The kit was stable even after ten months of storage at recommended temperature and showed good sensitivity. From the practical point of view, the kit studied has good reliability, and could be used in the routine application for the control of illegal use of the drug.

Clinical application of ionization density dependence of the glow curve for measuring linear energy transfer in therapeutic proton beams

Linear energy transfer (LET) is related to the relative biological effect caused by particle therapy. LET is a candidate parameter for optimizing proton therapy treatment plans by considering the biological effects. Therefore, being able to measure LET in clinical sites has become crucial. The purpose of this study was to develop a feasible LET measurement system for clinical therapeutic proton therapy by using the ionization density dependence of the heating-induced fluorescence (LiF):Mg,Ti glow curve in the high-temperature region. The integrated thermoluminescent (TL) intensity over the specified high-temperature region after exposure to a proton beam was divided by that after exposure to a photon beam to obtain the high-temperature ratio (HTR). The relationship between the HTR and LET was determined. TL dosimeters (TLDs) were irradiated with the same dose at several depths of a water phantom using three types of radiation: a60Co gamma source at the National Measurement Laboratory of the Institute of Nuclear Energy Research, a 6-MV photon beam, and a 190-MeV proton beam at Chang Gung Memorial Hospital. The LET dependence on depth was simulated using a Monte Carlo code called TOPAS (version 3.0.1). The LET values ranged from 1 to 10 keV/μm in estimations using LiF:Mg,Ti for a proton beam. The LET measurement system was developed by comparing TL signals caused by proton beams with those caused by 60Co gamma rays or 6-MV X-rays. A system incorporating Linac X-rays would be most convenient for the majority of hospitals. Therefore, TLDs can not only be dosimeters but also LET detectors in proton therapeutic sites.

Fabrication and Characterization of Metal-Supported Solid Oxide Fuel Cell Fabricated by Atmospheric Plasma Spraying

Institute of Nuclear Energy Research (INER) has been developing fabrication method for metal-supported solid oxide fuel cells (MS-SOFCs) operating in the range of 600-750oC. The planar MS-SOFC cell with 10×10 cm2 in size were fabricated by atmospheric plasma spraying. The measured powers of the MS-SOFC in cell test achieve 55, 44.6 and 28 W at 0.8 V and 750, 700 and 650oC, respectively. The power outputs of MS-SOFC single-cell stack are 54.7 and 44.3 W at 0.7 V and 750 and 700oC, respectively. The durability tests of the MS-SOFC cell had performed for 3,500 hours at the test condition of 400 mA/cm2 and 700oC. The measured degradation rate is less than 1 %/1000hr, which indicates that the plasma-sprayed MS-SOFC cell made by INER reveals an inspired performance.