• Journal of Radiation Industry
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• v.7 no.1
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• pp.37-43
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• 2013

We examined the forage quality to provide the basic information for the utilization of blackberry by-products (leaf and stem) among thirty-five mutant lines derived from gamma-ray. The leaves had higher crude protein (CP) contents than stems. In addition, the leaves showed broad ranges of variation in crude fat, crude fiber and crude ash. The overall forage quality of the stems were similar to those of the original variety. The mean of neutral detergent fiber (NDF) content of leaves and stems in mutant lines were 25.88% and 58.98%, respectively. Also, the mean of acid detergent fiber (ADF) content of leaves and stems in mutant lines were 15.43% and 49.27%, respectively. Forage quality grades of all blackberry leaf were special quality class. However, the blackberry stem ranked $1^{st}$ to $5^{th}$ in quality class. The stem diameter was negatively ($P{\leq}0.05$) correlated with the moisture and crude protein. Also, the fruit length was highly negatively ($P{\leq}0.01$) correlated with the RFV (relative feed value) in blackberry leaf. The one hundred fruit weight was highly negatively ($P{\leq}0.01$) correlated with the crude ash. Based on these results, the by-products of blackberry could provide high quality forage for feeding of live stock.

• Journal of Radiation Industry
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• v.6 no.4
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• pp.305-310
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• 2012

This study examined radiation detection properties of imported perilla seeds, almonds, and soybeans. Food samples were irradiated at doses of 0.5, 1, 2, and 4 kGy and analyzed by photo-stimulated luminescence (PSL), thermoluminescence (TL), and electron spin resonance (ESR). The results of PSL showed that photon counts of irradiated perilla seeds and soybeans were $32,959counts{\cdot}60sec^{-1}$ and $7,234counts{\cdot}60sec^{-1}$, respectively, at an irradiation dose of 0.5 kGy, and the photon count of irradiated almonds was $5,581counts{\cdot}60sec^{-1}$ at an irradiation dose of 1 kGy. The results of TL showed that this technique is useful for detecting irradiated samples; the TL ratios ($TL_1/TL_2$) measured for the food samples at an irradiation dose of 0.5 kGy were 0.2301 for perilla seeds, 0.4595 for almonds, and 0.4827 for soy beans. Lastly, results of ESR spectroscopy for only soybeans revealed specific signals derived from free radicals captured in the cellulose. In conclusion, PSL, TL, and ESR methods can be used for the detection of gamma-irradiated soybean samples, whereas gamma-irradiated perilla seeds and almonds can be confirmed by a serial detection with a TL method after PSL.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.17 no.1
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• pp.1-13
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• 2019

The accident at the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) resulted in the deposition of large quantities of radionuclides over parts of eastern Japan. Radioactive contaminants have been observed over a large area including forests, cities, rivers and lakes. Due to the strong adsorption of radioactive cesium by soil particles, radioactive cesium migrates with the eroded soil, follows the surface flow paths, and is delivered downstream of population-rich regions and eventually to coastal areas. In this study, we developed a model to simulate the transport of contaminated sediment in a watershed hydrological system and this model was compared with observation data from eroded soil observation instruments located at the Korea Atomic Energy Research Institute. Two methods were applied to analyze the soil particle size distribution of the collected soil samples, including standardized sieve analysis and image analysis methods. Numerical models were developed to simulate the movement of soil along with actual rainfall considering initial saturation, rainfall infiltration, multilayer and rain splash. In the 2019 study, a numerical model will be used to add rainfall shield effect by trees, evaporation effect and shield effects of surface water. An eroded soil observation instrument has been installed near the Wolsong nuclear power plant since 2018 and observation data are being continuously collected. Based on these observations data, we will develop the numerical model to analyze long-term behavior of radionuclides on land as they move from land to rivers, lakes and coastal areas.

• Korean Journal of Metals and Materials
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• v.49 no.8
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• pp.628-634
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• 2011

SA508 Gr.4N Ni-Cr-Mo low alloy steel, in which Ni and Cr contents are higher than in commercial SA508 Gr.3 Mn-Mo-Ni low alloy steels, may be a candidate reactor pressure vessel (RPV) material with higher strength and toughness from its tempered martensitic microstructure. The inner surface of the RPV is weld-cladded with stainless steels to prevent corrosion. The goal of this study is to evaluate the microstructural properties of the clad interface between Ni-Cr-Mo low alloy steel and stainless weldment, and the effects of post weld heat treatment (PWHT) on the properties. The properties of the clad interface were compared with those of commercial Mn-Mo-Ni low alloy steel. Multi-layer welding of model alloys with ER308L and ER309L stainless steel by the SAW method was performed, and then PWHT was conducted at $610^{\circ}C$ for 30 h. The microstructural changes of the clad interface were analyzed using OM, SEM and TEM, and micro-Vickers hardness tests were performed. Before PWHT, the heat affected zone (HAZ) showed higher hardness than base and weld metals due to formation of martensite after welding in both steels. In addition, the hardness of the HAZ in Ni-Cr-Mo low alloy steel was higher than that in Mn-Mo-Ni low alloy steel due to a comparatively high martensite fraction. The hardness of the HAZ decreased after PWHT in both steels, but the dark region was formed near the fusion line in which the hardness was locally high. In the case of Mn-Mo-Ni low alloy steel, formation of fine Cr-carbides in the weld region near the fusion line by diffusion of C from the base metal resulted in locally high hardness in the dark region. However, the precipitates of the region in the Ni-Cr-Mo low alloy steel were similar to that in the base metal, and the hardness in the region was not greatly different from that in the base metal.

• Journal of Radiation Industry
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• v.17 no.2
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• pp.127-134
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• 2023

Pharmacokinetic (PK) data provide pivotal information in drug development, and they are usually first studied in the preclinical stage using various animals. However, quite often, animal PK data may not match with human PK, especially in metabolites. Thus, most regulatory agencies in the world make it mandatory to obtain metabolite information using ¹⁴C radiolabeled drug in human for small molecule drug candidates. However, such studies are expensive and time consuming and they are usually done at the end of Phase II trials using ~3.7 MBq of ¹⁴C labeled drug in a limited number of human subjects. Introduction of accelerator mass spectrometry (AMS) in this kind of study has revolutionized it. Since AMS can measure ¹⁴C level as close as natural abundance, it can quantify the amounts of ¹⁴C labeled drugs and their metabolites produced in human body that consumes less than the amount of 0.0037 MBq of ¹⁴C labeled drug, a very safe level of radioactive dose in human. Therefore, it is now possible to conduct human ¹⁴C studies safely in early clinical trials without spending hefty amount of money and time. Korea Radioisotope Center for Pharmaceuticals(KRICP) at Korea Institute of Biological and Medical Sciences(KIRAMS) has established an AMS facility in 2018, housing a 0.5MV AMS manufactured at the US National Electrostatics Corps (NEC). The AMS instrument has been validated using various standard samples that have been prepared at Lawrence Livermore National Laboratory in the US, a worldly reputable provider of AMS standards. In this paper, we present a mass balance study for acetaminophen in rats using AMS and prove that the study results are equivalent with those of literature, which shows the AMS facilities at KRICP has successfully installed and be ready to be used in the various PK studies using ¹⁴C labelled compounds for new drug development.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.4 no.4
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• pp.353-363
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• 2006

In order to evaluate the potential radiological risks for the reuse of the site after decommissioning of nuclear facilities, a mathematical model was developed and materialized into the Microsoft $Excel{\circledR}$ spreadsheets frame. A set of input parameter values was proposed, which is useful in the preliminary risk screening step before the detailed evaluation with the site-specific data. It appeared that the screening levels calculated by the present model was agreed with the derived concentration guideline limits resulted from RESRAD Ver.6.2 and the German dose criteria for releasing a nuclear site from regulatory control.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.1 no.1
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• pp.1-10
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• 2003

As a follow up to the Agenda 21's policy statement for safe management of radioactive waste adopted at Rio Conference held in 1992, the UN invited the LAEA to develop and implement indicators of sustainable development for the management of radioactive waste. The IAEA finalized the indicators in 2002, and is planning to calculate the member states' values of indicators in connection with operation of its Net-Enabled Waste Management Database system. In this paper, the basis for introducing the indicators into the radioactive waste management was analyzed, and calculation methodology and standard assessment procedure were simply depicted. In addition, a series of innate limitations in calculation and comparison of the indicators was analyzed. According to the proposed standard procedure, the indicators for a few major countries including Korea were calculated and compared, by use of each country's radioactive waste management framework and its practices. In addition, a series of measures increasing the values of the indicators was derived so as to enhance the sustainability of domestic radioactive waste management program.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.12 no.1
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• pp.43-49
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• 2007

The methods of physical oceanographic surveys to examine the effect of thermal discharge from nuclear power plants in Korea have been reviewed and a standard guide to the survey is proposed. It is desirable that in situ observation and numerical thermal diffusion modeling are conducted simultaneously to describe the variation in temperature distribution affected by thermal discharge from a power plant because any observation or numerical modeling alone has limits to do so quantitatively. It is suggested that the field observation must be based on the concept of heat budget modeling considering all artificial and natural heat sources/sinks around the power plant. Any results from numerical modeling must reach to a certain statistical significance level to use for a standard temperature distribution. In addition, the development of standard numerical codes is proposed to improve the problems shown in the past numerical circulation and diffusion modelling.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.4 no.2
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• pp.171-178
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• 2006

Decommissioning cost estimation is a very important technique in designing and planning of nuclear facilities' decommissioning. Decommissioning cost estimation should be made according to the phases of decommissioning activities and installed components of nuclear facilities. In this paper, the basic framework necessary for decommissioning cost estimation is completed so that it could be used as a technique for decommissioning costs estimation by specifying cost items and group components and unit cost factors on which work time is calculated. Also, factors to be considered for decommissioning cost estimation of major activities and tasks are reviewed. Afterwards, these techniques will be utilized as a basic technology to establish methodology of decommissioning cost estimation and evaluation.

• Journal of Radiation Industry
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• v.5 no.1
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• pp.15-20
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• 2011

Protein kinases are the most important drug targets for the treatment of numerous diseases. The involvement of protein kinase C (PKC) in many biological processes such as development, memory, cell differentiation, and proliferation has been demonstrated. PKC is recognized as an important player in carcinogenesis. Thus, a variety of PKC inhibitors have been investigated. Among them, flavonoids have been demonstrated to affect the activity of many mammalian in vitro enzyme systems. The recent investigation was performed to evaluate the inhibitory effects of hesperidin, which is a flavonoid, on the proliferation and carcinogenesis of many cancers. In this study, an efficient kinase assay based on a biochip using radio-phosphorylation was established and performed for an examination of the inhibitory effects of hesperidin on PKC activity at different concentrations of 50, 200, 500 nM. It was found that hesperidin shows inhibitory potency on PKC, and that the biochip can be used to rapidly screen kinase inhibitors resulting in the therapeutic agents.