http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
김동학 ( Kim¸ Dong-hak ),김상준 ( Kim¸ Sang-jun ),유승봉 ( Yu¸ Seung-bong ),박기쁨 ( Bak¸ Gippeum ) 한국환경복원기술학회 2021 한국환경복원기술학회지 Vol.24 No.4
This study suggested suitable soil textures that is proper to propagate native plants to manage and restore barren land in DMZ. Germination tests were conducted for 16 native herbaceous plants growing in the DMZ border area in accordance with FAO-BI (Biodiversity International) standards, and the germination rate and T<sub>50</sub> in vitro were investigated. In order to examine the germination characteristics according to the soil textures, we used gravel, bed and mixed soil and investigated the germination characteristics under ordinary room temperature conditions in the greenhouse. As a result, it was observed that the germination rate in the greenhouse was significantly decreased compared to the germination rate in vitro of the species advertised due to soil textures. T<sub>50</sub> between the in vitro and each soil texture showed significant differences whereas T<sub>50</sub> between soil textures alone did not in all species advertised. The germination rate in vitro of Aster koraiensis, Dendranthema zawadskii var. latilobum, Hosta clausa , and Hosta minor there was no significant difference compared to ordinary room temperature conditions. In addition, as the germination rate is demonstrated more than 70%, which is relatively higher than other species advertised, it is considered to have strong environmentally adaptable. On the other hand, considering that the 6 species of Leontopodium coreanum, Plantago major , Potentilla chinensis, Sedum kamtschaticum, Sedum latiovalifolium, and Veronica kiusiana demonstrated less than 50% of germination rate in vitro, it is expected to be difficult to propagate without pre-treatment. In order to use these 6 species as restoration material plants, it needs to be considered to pre-treat to improve germination rate, or to enhance the vitality of seeds by improving the seed gathering period and storage method.
Donghak Kim,Young-Ran Lim,Hyoung-Goo Park,Beom Joon Kim,Young-Jin Chun 한국독성학회 2009 Toxicological Research Vol.25 No.1
TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin) and related halogenated aromatic hydrocarbons elicit a diverse spectrum of biochemical and toxic responses in laboratory animals and mammalian cells in culture. Toxicity and carcinogenicity of TCDD is well established but the molecular mechanism is still poorly understood. Here, we found the noble responsive genes to TCDD using the differential display analysis. Treatment of HepG2 cells with TCDD showed a significantly different mRNA expression pattern from the untreated cells in differential display analysis. The differentially displayed bands were isolated and used as probes in dot blot and Northern blot analyses. Of thirty-five isolated differentially displayed bands, only two bands were confirmed as positive in dot blot and Northern blot analyses. The nucleotides sequences of these clones were analyzed and the search of Genebank database revealed that one clone is highly homologous with RanBP2 (Ras-related nuclear protein binding protein2; 92%) and the other is an unknown gene. RanBP2 is a nucleoporin with SUMO E3 ligase activity that functions in both nucleocytoplasmic transport and mitosis and its role as a novel tumor suppressor has been recently proposed. Thus, these results may suggest the clue elucidating the toxic mechanism of TCDD through RanBP2.
Human Cytochrome P450 Metabolic Activation in Chemical Toxicity
Donghak Kim,Young-Jin Chun 한국독성학회 2007 Toxicological Research Vol.23 No.3
Cytochrome P450 (P450) enzymes are the major catalysts involved in the biotransformation of various drugs, pollutants, carcinogens, and many endogenous compounds. Most of chemical carcinogens are not active by themselves but they require metabolic activation. P450 isozymes play a pivotal role in the metabolic activation. The activation of arylamines and heterocyclic arylamines (HAAs) involves critical N-hydroxylation, usually by P450. CYP1A2 plays an important role in these reactions. Broad exposure to many of these compounds might cause carcinogenicity in animals and humans. On the other hand, P450s can be also involved in the bioactivation of other chemicals including alcohols, aflatoxin B1, acetaminophen, and trichloroethylene, both in humans and in experimental animals. Understanding the P450 metabolic activation of many chemicals is necessary to develop rational strategies for prevention of their toxicities in human health. An important part is the issues of extrapolation between species in predicting risks and variation of P450 enzyme activities in humans.
Collaborative R&D Work Between Korea and USA for Cooling Rate Effect of Hydride Reorientation
Donghak Kook,Hongryoul Oh,Daeho Kim,Yanghyun Koo 한국방사성폐기물학회 2022 한국방사성폐기물학회 학술논문요약집 Vol.20 No.1
Laboratory testing to simulate the drying of spent fuel is most often done using a cooling rate of approximately 5°C per hour because there are so many restricted test conditions like R&D project duration limit, budget and temporary electronic supply blackout at laboratory building. However, in a real dry cask storage system, the fuel cools much slower. Early data from KAERI on unirradiated, pre-hydrided cladding has shown that slower cooling may result in more brittle behavior than is currently observed based on these short-term tests. Given the potential safety and future handling implications of failed fuel, it is important to determine if the material properties of spent fuel cladding measured in these laboratory tests are the same as would be observed on fuel that has undergone a much longer, slower cooling, which may provide more time for hydrides to precipitate in the radial direction. KAERI and PNNL have started a collaborative I-NERI R&D project on this topic and each organization will perform tests on unirradiated & irradiated cladding under various hoop stress and cooling rate combinations. Scope of collaborative work is to evaluate long-term cooling (slow cooling rate) on hydride reorientation and subsequent material properties of cladding to determine if past and current research activities on spent nuclear fuel are bounding. The results will be used to direct future testing and help predict cladding performance over a wide range of burnups during extended storage and transportation.
PYROPROCESS WASTE DISPOSAL SYSTEM DESIGN AND DOSE CALCULATION
DONGHAK KOOK,DONG-KEUN CHO,Min-Soo Lee,JONGYOUL LEE,HEUI-JOO CHOI,김용수 한국원자력학회 2012 Nuclear Engineering and Technology Vol.44 No.5
PWR spent fuels produced in the Republic of Korea are expected to be recycled by pyroprocess in the long term future. Even though pyroprocess waste amounts can be smaller than that of PWR spent fuel assembly in case of direct disposal, this process essentially will produce various and unique radioactive wastes. The goals of this article are to characterize these wastes, calculate the amount of wastes, design disposal systems for each waste and evaluate the radiation safety of each system by dose assessment. The absorbed dose results of the metal and ceramic waste for the engineering barrier system (EBS) showed 2.21 x 10-2 Gy/h and 1.15 x 10-2 Gy/h, which are lower than the recommended value of 1 Gy/h. These results confirmed that the newly proposed disposal systems have a safety margin for the radiation produced from each waste.
김동학(Donghak Kim),윤영한(Younghan Youn),이재완(Jaewan Lee) 한국자동차공학회 2002 한국자동차공학회 Symposium Vol.2002 No.11
To impreve Child Occupant safety, US adopt a requirement for universal, uniform anchor systems for child restraints, an enormous effort of some child seat manufacturers tried to improve the protective properties of Child Restraint System(CRS). The new standard includes FMVSS 225, Child Restriant Anchorage Systems and Amendments to FMVSS 213 came into effect in 1999. The rules of universal anchor are to provide devices which are independent of safety belts to attach child restraints to the vehicle. It will allow child restraints are anchored more securely than those are often possible with current safety belts. Recently, US, Australia and Euripean community countris including Japan have started testing of evaluation of CRS performances during their NCAP test programs and results were published.<br/> Koran govemment realized the importacne of CRS roles in child safety and investigate benefits of enhancements of CRS regulations. In this study, four kinds of ISOFIX were simulated by commercial program as well as the current CRS and were evaluated in order to verity their safety for Child Occupant.