• Journal of Plant Biology
• /
• v.11 no.1
• /
• pp.1-6
• /
• 1968

The effects of the different temperatures on the amylase activity and growth rate of the rye seedling grown in the solutions containing radioactive sulfur- 35 were studied. The amylase activity of the coleoptiles obtained from the seedlings grown in the solutions of S-35, at 14$^{\circ}C$, appeared to be strongly stimulated in comparison to the control, but the culture temperatures of 22$^{\circ}C$ and 3$0^{\circ}C$ showed the decrease in the amylase activity. The amylase activity of the grains treated with the low intensity of the ratioactive material didn't show clear changes, at any culture temperatures, but the amylase activity of the grains treated with the high intensity of S-35, 50$\mu$c, showed definite decline at the elevated culture temperature, 3$0^{\circ}C$. Similar effects was also found in the growth of the seedlings. However, we would consider the effects of the radioactive materials on the acticity of the amylase and the growth of the seedlings are resulted from the accumulation of the much amount of the radioactive materials, and this accumulation rate depends upon actually the elevation of the culture temperature.

• Proceedings of the Korean Radioactive Waste Society Conference
• /
• 2003.11a
• /
• pp.162-167
• /
• 2003

The pool $(3m{\times}6m{\times}10m)$ in Irradiated Materials Examination Facility is usually used for the purpose of taking the specimen out of cask loaded into the pool, and carrying in/out the specimen to/from the hot cell. Always, it must be cared for the water into the pool to be fine condition because all operation are worked with the naked eye during taking an irradiated materials out of the cask and plunging them in the bucket-elevator. In the aspects of the radioactive contamination control, remained substances in the water must be controlled so that the amount of substances are to be lower than the standard amount prescribed by RCA Korea Activity in a part of radioactive contamination control. This paper describes a behavior of the quality of water and the radioactive contamination of pool water for working of pool water purging system and contamination diffusion distribution bahavior of each specimens carried in/out.

• Maritime Security
• /
• v.2 no.1
• /
• pp.125-149
• /
• 2021

Even 10 years after the Fukushima nuclear disaster, Japan has yet to solve the problems emerging from generating contaminated water every day. Japan has unilaterally decided to release nuclear wastewater in the sea despite Korea's concerns about safety as their radioactive water storage tanks reach the limits. Despite Korea's response, Japan is still preparing to discharge nuclear wastewater without fulfilling its obligations under the United Nations Convention on the Law of the Sea. There are concerns about marine pollution caused by the radioactive materials from nuclear wastewater and invading Korea's maritime sovereignty. In particular, it is impossible to reverse the effects of environmental pollution, so plans to discharge radioactive water must be prevented unless immediate safety is guaranteed. This study proposes Korea's response strategy to resolve the conflict between the two countries due to plans to release contaminated water. Korea should respond to Japan's release of nuclear wastewater in the sea in various ways through cooperation with Japan, provisional measures, and cooperation with neighboring countries.

• Transactions of the Korean Society of Pressure Vessels and Piping
• /
• v.16 no.1
• /
• pp.37-41
• /
• 2020

The Nuclear containment building is a main safety-related structure that performs shielding and conservation functions to prevent highly radioactive materials from leakage to the outside environment in the case of various environmental conditions and postulated accidents. The containment building contains a reactor, steam generator, pressurizer, tank, reactor coolant system, auxiliary system and engineering safety system, and is designed so that highly radioactive materials above the limits specified in 10 CFR 100 do not escape to the outside environment in the case of LOCA(Loss of Coolant Accident) for instance. The containment metal liner plate(CLP) is a carbon steel plate with a nominal plate thickness of 6 mm, which functions as a mold for the wall and dome of the containment building when concrete is filled, fulfills airtightness to prevent leakage of seriously radioactive materials. In recent years, backside corrosion was found on the liner plate in some domestic nuclear power plants. The main cause of backside corrosion was unfilled concrete. In this paper, an inspection technique of assessing filling suitability for CLP backside concrete is developed. Results show that the validity of inspection technique for CLP backside concrete using vibration sensor is successfully verified.

• Proceedings of the Korean Radioactive Waste Society Conference
• /
• 2005.11b
• /
• pp.290-299
• /
• 2005

Two decommissioning projects are carried out at the KAERI (Korean Atomic Energy Research Institute), one for the Korea research reactors, KRR-1 and KRR-2, and another for the uranium conversion plant (UCP). The concept of the management of the wastes from the decommissioning sites was reviewed with a relation of the decommissioning strategies, technologies for the treatment and the decontamination, and the characteristics of waste. All the liquid waste generated from KRR-1 and KRR-2 decommissioning site is evaporated by a solar evaporation facility and all the liquid waste from the UCP is treated together with lagoon sludge waste. The solid wastes from the decommissioning sites are categorized into three groups; not contaminated, restricted releasable and radioactive waste. The not-contaminated waste will be reused and/or disposed at an industrial disposal site, and the releasable waste is stored for the future disposal at the KAERI. The radioactive waste is packed in containers, and will be stored at the decommissioning sites till they are sent to a national repository site. The reduction of the radioactive solid waste is one of the strategies for the decommissioning projects and could be achieved by the repeated decontamination. By the achievement of the minimization strategy, the amount of radioactive waste was reduced and the disposal cost will be reduced, but the cost for manpower, for direct materials and for administration was increased.

• Nuclear Engineering and Technology
• /
• v.49 no.8
• /
• pp.1772-1777
• /
• 2017

Korean nuclear power plants (NPPs) periodically evaluate the radioactive gaseous and liquid effluents released from power reactors to protect the public from radiation exposure. This paper provides a comprehensive overview of the release of radioactive effluents from Korean NPPs and the effects on the annual radiation doses to the public. The amounts of radioactive effluents released to the environment and the resulting radiation doses to members of the public living around NPPs were analyzed for the years 2011-2015 using the Korea Hydro & Nuclear Power Co., Ltd's annual summary reports of the assessment of radiological impact on the environment. The results show that tritium was the primary contributor to the activity in both gaseous and liquid effluents. The averages of effective doses to the public were approximately on the order of $10^{-3}mSv$ or $10^{-2}mSv$. Therefore, even though Korean NPPs discharged some radioactive materials into the environment, all effluents were within the regulatory safety limits and the resulting doses were much less than the dose limits.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2022.11a
• /
• pp.167-168
• /
• 2022

Recently, starting with the permanent suspension of Gori 1 in Korea, the importance of the disposal of concrete structures in nuclear power plants has emerged, and environmental and safety are required to be proved accordingly. Safe radioactive waste disposal technology that immobilizes harmful radioactive elements, which are by-products of nuclear power, inside a solid matrix and recycling measures are needed to secure an efficient waste disposal space. This study was conducted to confirm whether recycled cement generated in the process of radioactive concrete treatment can be used as a solidifying material for radioactive waste treatment. In order to simulate the concrete exposed to radiation, aqueous solutions of Di-water, CsCl 1M, and CoCl₂ 1M were used as blending water at W/B 0.5. Tricalcium phosphate and Prussian blue were substituted with 5 wt.% based on the weight of recycled cement as a binder to improve solidification performance, and their hydration characteristic was analyzed.

• The Journal of Engineering Geology
• /
• v.24 no.4
• /
• pp.535-550
• /
• 2014

The origins and varieties of natural radioactive materials, including uranium and radon-222, were examined in a drilled borehole extending to a depth of 120 m below the surface in the Goesan area. In addition to core samples, eight groundwater samples were collected at different depths, using a double packer system and bailer, and their geochemical characteristics were determined. Most of the rock samples from the drilled core consisted of granite porphyry, with sedimentary rocks (slate, carbonate, or lime-silicates) and pegmatite occurring in certain sections. The pH of samples varied from 7.8 to 8.4, and the groundwater was of a Na-$HCO_3$type. Uranium and thorium concentrations in the core were < 0.2-14.8 ppm and 0.56-45.0 ppm, respectively. Observations by microscope and an electron probe microanalyzer (EPMA) showed that the mineral containing the natural radioactive materials was monazite contained in biotite crystals. The uranium, which substituted for major elements in the monazite, appeared to have dissolved and been released into the groundwater in a shear zone. Concentrations of Radon-222 in the borehole showed no close relationship with levels of uranium. The isotopes of noble gases, such as helium and neon, would be useful for analyzing the origins and characteristics of the natural radioactive materials.

• Proceedings of the Korea Technology Innovation Society Conference
• /
• 2003.11a
• /
• pp.369-386
• /
• 2003

Radiation technologies are being utilized in a wide range of daily modern life and provide the public with valuable benefits through applications in fields of medical, industrial, agricultural, and science & engineering research. On the other hand, there is a high possibility that radioactive materials can be used for malevolent purposes such as dirty bombs. The International community, therefore, has made efforts to improve the security of radioactive sources aimed at protecting the public from radiological terrorism. The paper investigated high-risk radioactive sources which could be used as dirty bombs. The paper reviewed the possibility of radiological weapon attacks and analyzed international trends to enhance security of radioactive sources. This study also proposed our countermeasures to reduce the threat of radiological terrorism and to properly respond to the radiological emergency caused by the radiological weapon attack.

• Nuclear Engineering and Technology
• /
• v.46 no.4
• /
• pp.461-466
• /
• 2014

Security of radioactive sources has been an issue since the earliest days of safety regulation of such materials. Since the events of September 11 2001, some governments and regulatory bodies have been much more focussed on these issues and have introduced extensive and enhanced security arrangements. International organisations like the IAEA and WINS have worked hard to help States in this regard. However, only a minority of States have implemented statutory security systems for radioactive source security. Why have so many States still to take action? What can be done to encourage and support these changes? This paper will offer some possible explanations for the lack of action in so many States and some potential answers to these questions.