• Title/Summary/Keyword: co-cycle

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Spatial Distributions of $^3H$ and $^{14}C$ in the Shielding Concrete of KRR-2 (연구로 2호기 수조 콘크리트의 $^3H$$^{14}C$ 공간분포)

  • Hong, Sang-Bum;Kim, Hee-Reyoung;Chung, Kun-Ho;Kang, Mun-Ja;Jeong, Gyeong-Hwan;Chung, Un-Soo;Park, Jin-Ho
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.4 no.4
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    • pp.329-334
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    • 2006
  • The depth distributions of total $^3H$ and $^{14}C$ activities were characterized for the activated shielding concrete from a decommissioning of KRR-2 using the commercially available tube furnace and a liquid scintillation counter. The correlation of measurement results between $^3H,\;^{14}C$ and gammer emitter was evaluated to apply for estimating radionuclide inventory of the concrete waste generated from decommissioning KRR-2. The detection limits for $^3H$ and $^{14}C$ are 0.048 and 0.028 Bq/g respectively. The specific activities of the $^3H$ and $^{14}C$ tend to decrease exponentially as the depth of the concrete becomes deeper from the surface. In addition, the $^3H$ and $^{14}C$ activities were in good correlation with the $^{60}CO$ activities analysed for the shielding concrete of KRR-2.

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Radwaste characteristics and Disposal Facility Waste Acceptance Criteria (국내 방사성폐기물 특성과 방사성폐기물 처분시설 폐기물인수기준)

  • Sung, Suk-Hyun;Jeong, Yi-Yeong;Kim, Ki-Hong
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.6 no.4
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    • pp.347-356
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    • 2008
  • The purpose of Radioactive Waste Acceptance Criteria(WAC) is to verify a radioactive waste compliance with radioactive disposal facility requirements in order to maintain a disposal facility's performance objectives and to ensure its safety. To develop WAC which is conformable with domestic disposal site conditions, we furthermore analysed the WAC of foreign disposal sites similar to the Kyung-Ju disposal site and the characteristics of various wastes which are being generated from Korea nuclear facilities. Radioactive WAC was developed in the technical cooperation with the Korea Atomic Energy Research Institute in consideration of characteristics of the wastes which are being generated from various facilities, waste generators' opinions and other conditions. The established criteria was also discussed and verified at an advisory committee which was comprised of some experts from universities, institutes and the industry. So radioactive WAC was developed to accept all wastes which are being generated from various nuclear facilities as much as possible, ensuring the safety of a disposal facility. But this developed waste acceptance criteria is not a criteria to accept all the present wastes generated from various nuclear facilities, so waste generators must seek an alternative treatment method for wastes which were not worth disposing of, and then they must treat the wastes more to be acceptable at a disposal site. The radioactive disposal facility WAC will continuously complement certain criteria related to a disposal concentration limit for individual radionuclide in order to ensure a long-term safety.

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Characteristics in Organic Carbon Distribution in the Seamangeum Area During the Construction of Artificial Sea Dike, Korea (방조제 건설에 따른 새만금 표층 유기탄소 분포 특성)

  • Park, Jun-Kun;Kim, Eun-Soo;Kim, Kyung-Tae;Cho, Sung-Rok;Song, Tae-Yoon;Yoo, Jeong-Kyu;Kim, Seong-Soo;Park, Yong-Chul
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.12 no.2
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    • pp.75-83
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    • 2009
  • In order to understand the impacts of the construction of artificial sea dikes on carbon cycle in Samangeum area being a closed environment after April, 2006, we had measured suspended particulate matters, particulate and dissolved organic carbon in the surface water of inner Saemangeum dike from 2003 to 2006. The significant inputs of suspended particulate matter and organic carbon were mainly occurred during the wet season which suggests that most organic matter loading is concentrated within a short period of time inside the dike. The concentrations of particulate matter and organic carbon have gradually increasing every year inside of dike from the Mangyeong river estuary to Saemangeum dike, which has been closed since 2003 after the construction of the 4th dike. The particulate organic carbon increased due to the phytoplankton blooms by eutrophication. If the large portion of particulate organic matter produced in the surface water sink to the bottom sediment, this will cause the anoxic condition in this closed environment.

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Effect of Fast Charging Mode on the Degradation of Lithium-Ion Battery: Constant Current vs. Constant Power (정전류/정출력 고속충전 방식에 따른 리튬이온전지의 열화 비교 연구)

  • Park, Sun Ho;Oh, Euntaek;Park, Siyoung;Lim, Jihun;Choi, Jin Hyeok;Lee, Yong Min
    • KEPCO Journal on Electric Power and Energy
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    • v.6 no.2
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    • pp.173-179
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    • 2020
  • Electric vehicles (EVs) using lithium secondary batteries (LIBs) with excellent power and long-term cycle performance are gaining interest as the successors of internal combustion engine (ICE) vehicles. However, there are few systematic researches for fast charging to satisfy customers' needs. In this study, we compare the degradation of LIB where its composition is LiNi0.5Co0.2Mn0.3/Graphite with the constant current and constant power-charging method. The charging speed was set to 1C, 2C, 3C and 4C in the constant current mode and the value of constant power was calculated based on the energy at each charging speed. Therefore, by analyzing the battery degradation based on the same charging energy but different charging method; CP charging method can slow down the battery degradation at a high rate of 3C through the voltage curve, capacity retention and DC-IR. However, when the charging rate was increased by 4C or more, the deviation between the LIBs dominated the degradation than the charging method.

Sequencing of cDNA Clones Expressed in Adipose Tissues of Korean Cattle

  • Bong, J.J.;Tong, K.;Cho, K.K.;Baik, M.G.
    • Asian-Australasian Journal of Animal Sciences
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    • v.18 no.4
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    • pp.483-489
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    • 2005
  • To understand the molecular mechanisms that regulate intramuscular fat deposition and its release, cDNA clones expressed in adipose tissues of Korean cattle were identified by differential screening from adipose tissue cDNA library. By partial nucleotide sequencing of 486 clones and a search for sequence similarity in NCBI nucleotide databases, 245 clones revealed unique clones. By a functional grouping of the clones, 14% of the clones were categorized to metabolism and enzyme-related group (stearoyl CoA desaturase, lactate dehydrogenase, fatty acid synthase, ATP citrate lyase, lipoprotein lipase, acetyl CoA synthetase, etc), and 6% to signal transduction/cell cycle-related group (C/EBP, cAMP-regulated phosphoprotein, calmodulin, cyclin G1, cyclin H, etc), and 4% to cytoskeleton and extracellular matrix components (vimentin, ankyrin 2, gelosin, syntenin, talin, prefoldin 5). The obtained 245 clones will be useful to study lipid metabolism and signal transduction pathway in adipose tissues and to study obesity in human. Some clones were subjected to full-sequencing containing open reading frame. The cDNA clone of bovine homolog of human prefoldin 5 gene had a total length of 959 nucleotides coding for 139 amino acids. Comparison of the deduced amino acid sequences of bovine prefoldin 5 with those of human and mouse showed over 95% identity. The cDNA clone of bovine homolog of human ubiquitin-like/S30 ribosomal fusion protein gene had a total length of 484 nucleotides coding for 133 amino acids. Comparison of the deduced amino acid sequences of bovine ubiquitin-like/S30 ribosomal fusion protein gene with those of human, rat and mouse showed over 97% identity. The cDNA clone of bovine homolog of human proteolipid protein 2 mRNA had a total length of 928 nucleotides coding for 152 amino acids. Comparison of the deduced amino acid sequences of bovine proteolipid protein 2 with those of human and mouse showed 87.5% similarity. The cDNA clone of bovine homolog of rat thymosin beta 4 had a total length of 602 nucleotides coding for 44 amino acids. Comparison of the deduced amino acid sequences of bovine thymosin beta 4 gene with those of human, mouse and rat showed 93.1% similarity. The cDNA clone of bovine homolog of human myotrophin mRNA had a total length of 790 nucleotides coding for 118 amino acids. Comparison of the deduced amino acid sequences of bovine myotrophin gene with those of human, mouse and rat showed 83.9% similarity. The functional role of these clones in adipose tissues needs to be established.

Acceleration of DNCB-induced Early-apoptosis via Activation of Corticotropin Releasing Factor in the Hair Root of NC/Nga Mice (DNCB로 유도된 NC/Nga 아토피피부염마우스에서 부신피질자극호르몬방출인자 활성에 따른 모발세포의 초기세포사멸 연구)

  • Park, Gunhyuk;Jang, Eunyoung;Kim, Seongbae;Han, Eunyoung;Kim, Yong-ung
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.43 no.4
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    • pp.281-287
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    • 2017
  • Stress in skin plays a significant role in both the direct/indirect regulation of cellular processes occurring in hair, which in turn affect the hair cycle. However, experimental data regarding the effects of stress-related corticotropin releasing factor (CRF) released by stress on the apoptotic process involved in hair is limited. Therefore, we investigated the acceleration of early-stage apoptosis induced by atopy-related stress using a 2,4-dinitrochlorobenzene NC/Nga mice model. Expression of CRF, its related proteins, annexin V, and mitochondrial dysfunction were measured by immunohistochemical analyses. Atopic stress strongly stimulated stress hormones response, such as CRF and adrenocorticotropic hormone, in outer epithelial sheath of the hair. Moreover, its stress induced mitochondrial damage and early-stage apoptosis of cells in hair root. These findings suggest that hair damage due to apoptosis in atopy model is accelerated in a high CRF environment. Importantly, the effect of stress-related CRF on apoptosis processes involved in atopy dermatitis-related hair loss, suggests that the CRF-regulating development or maintenance materials may provide effective therapeutic strategies for hair health.

The Electrochemical Characteristics of Hybrid Capacitor Prepared by Chemical Activation of NaOH (NaOH 화학적 활성화로 제조된 하이브리드 커패시터의 전기화학적 특성)

  • Choi, Jeong Eun;Bae, Ga Yeong;Yang, Jeong Min;Lee, Jong Dae
    • Korean Chemical Engineering Research
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    • v.51 no.3
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    • pp.308-312
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    • 2013
  • Active carbons with high specific surface area and micro pore structure were prepared from the coconut shell char using the chemical activation method of NaOH. The preparation process has been optimized through the analysis of experimental variables such as activating chemical agents to char ratio and the flow rate of gas during carbonization. The active carbons with the surface area (2,481 $m^2/g$) and mean pore size (2.32 nm) were obtained by chemical activation with NaOH. The electrochemical performances of hybrid capacitor were investigated using $LiMn_2O_4$, $LiCoO_2$ as the positive electrode and prepared active carbon as the negative electrode. The electrochemical behaviors of hybrid capacitor using organic electrolytes ($LiPF_6$, $TEABF_4$) were characterized by constant current charge/discharge, cyclic voltammetry, cycle and leakage tests. The hybrid capacitor using $LiMn_2O_4$/AC electrodes had better capacitance than other hybrid systems and was able to deliver a specific energy as high as 131 Wh/kg at a specific power of 1,448 W/kg.

A Study on the Emissions Characteristics of a LPG Vehicle According to Various Test Modes and Ambient Conditions (다양한 시험모드와 환경조건에 따른 LPG 차량의 배출특성 연구)

  • Lee, Min-Ho;Ha, Jong-Han
    • Journal of the Korean Institute of Gas
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    • v.19 no.4
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    • pp.1-7
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    • 2015
  • As the interest on the air pollution is gradually rising up at home and abroad, automotive and fuel researchers have been working on the exhaust emission reduction from vehicles through a lot of approaches, which consist of new engine design, innovative after-treatment systems, using clean (eco-friendly alternative) fuels and fuel quality improvement. This research has brought forward various main issues : whether PM emissions should be regulated for diesel and gasoline vehicles and whether gasoline and LPG powered vehicles can be further neglected from PM emission inventories. Finally, the greenhouse gas regulation has been discussed including automotive emission regulation. The greenhouse gas and emissions of automotive had many problem that cause of ambient pollution, health effects. Based on various test modes and ambient conditions, this paper discusses the characteristics of LPG on exhaust emissions and greenhouse gases. Also, this paper assessed emission characteristics due to the test temperature. These test temperature were performed by dividing the temperature of the test mode and the lowest local temperature in winter. Through this study, the correlation of vehicle test mode and ambient condition, exhaust emission, greenhouse gas emission was analyzed.

The Establishment of Service Cloud Based Expansion and Developing Plan for National Spatial Data Infrastructure (서비스 클라우드 기반 국가공간정보통합체계 확대발전방안 수립)

  • Youn, Junhee
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.1
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    • pp.367-373
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    • 2016
  • The construction of National Spatial Data Infrastructure (NSDI) started from 2008 and was completed at 2012, with the aim of co-utilizing public agencies' national spatial information by integrating and linking. Despite the existence of the NSDI, an update of spatial data is not fully reflected because the spatial information has not been updated simultaneously by NSDI and public agencies. By examining the public agencies' services using the spatial information, a national budget is wasted because the re-usable similar services are duplicated. These issues could be solved by adopting a cloud system, whose concept is co-utilizing IT resources, to the NSDI. This study examined the service cloud based expansion and development plan for NSDI. The plan included an implementation strategy for a spatial information service cloud system and an establishment plan for a governance system. The service scenarios, concept diagram, and service functions for the system were derived in a system implementation plan. For the service functions, the unit functions of two modules were proposed and specific functions were derived. In the establishment of a governance system, the business roles and business processes were defined for organizations managing service cloud based NSDI. The business role and process were defined and derived by each service life-cycle step. With the proposed system implementation plan, a detail system design and composition of the organization could be possible, and a service cloud-based NSDI system could be implemented.

A study on the electrodeposition of uranium using a liquid cadmium cathode at 440℃ and 500℃ (440℃와 500℃에서 액체카드뮴음극을 이용한 우라늄 전착에 관한 연구)

  • Yoon, Jong-Ho;Kim, Si-Hyung;Kim, Gha-Young;Kim, Tack-Jin;Ahn, Do-Hee;Paek, Seungwoo
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.11 no.3
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    • pp.199-206
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    • 2013
  • Electrowinning process in pyroprocessing recovers U (uranium) and TRU (Trans Uranium) elements simultaneously from spent fuels using a liquid cadmium cathode (LCC). When the solubility limit of U deposits over 2.35wt% in Cd, U dendrites were formed on the LCC surface during the electrodeposition at $500^{\circ}C$. Due to the high surface area of dendritic U, the deposits were not submerged into the liquid cadmium pool but grow out of the LCC crucible. Since the U dendrites act as a solid cathode, it prevents the co-deposition of U and TRUs. In this study, the electrodeposition of U onto a LCC was carried out at 440 and $500^{\circ}C$ to compare the morphology and component of U deposits. The U deposits at $440^{\circ}C$ have a specific shape and were stacked regularly at the center of the LCC pool, while the U dendrites (i.e., ${\alpha}$-phase) at $500^{\circ}C$ were grow out of the LCC crucible. Through the microscopic observation and XRD analysis, the electrodeposits at $440^{\circ}C$, which have a round shape, were identified as an intermetallic compound such as $UCd_{11}$. It can be concluded that the LCC electrowinning operation at $440^{\circ}C$ achieves the co-recovery of U and TRU without the formation of U dendrites.