• Title/Summary/Keyword: 우주폐기물

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Synthesis of Various Biomass-derived Carbons and Their Applications as Anode Materials for Lithium Ion Batteries (다양한 바이오매스 기반의 탄소 제조 및 리튬이온전지 음극활물질로의 응용)

  • Chan-Gyo Kim;Suk Jekal;Ha-Yeong Kim;Jiwon Kim;Yeon-Ryong Chu;Hyung Sub Sim;Chang-Min Yoon
    • Journal of the Korea Organic Resources Recycling Association
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    • v.31 no.3
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    • pp.27-34
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    • 2023
  • In this study, various plant-based biomass are recycled into carbon materials to employ as anode materials for lithium-ion batteries. Firstly, various biomass of rice husk, chestnut, tea bag, and coffee ground are collected, washed, and ground. The carbonization process is followed under a nitrogen atmosphere at 850℃. The morphological and chemical properties of materials are investigated using FE-SEM, EDS, and FT-IR to compare the characteristic differences between various biomass. It is noticeable that biomass-derived carbon materials vary in shape and degree of carbonization depending on their precursor materials. These materials are applied as anode materials to measure the electrochemical performance. The specific capacities of rice husk-, chetnut-, tea bag-, and coffee ground-derived carbon materials are evaluated as 65.8, 80.2, 90.6, and 104.7 mAh g-1 at 0.2C. Notably, coffee ground-based carbon exhibited the highest specific capacity owing to the difference in elemental composition and the degree of carbonization. Conclusively, this study suggests the possibility of utilizing as energy storage devices by employing various plant-based biomass into active materials for anodes.

Determinations of the Exposure Rate Using a NaI(Tl) Detector of the Environmental Radiation Monitor (환경방사선감시기의 NaI(Tl) 검출기를 이용한 조사선량률 결정방법)

  • Ji, Young-Yong;Lee, Wanno;Choi, Sang-Do;Chung, Kun Ho;Kang, Mun Ja;Choi, Geun-Sik
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.11 no.3
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    • pp.245-251
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    • 2013
  • The energy band and the G-factor method were compared to determine the exposure rate from the measured spectrum using a NaI(Tl) scintillation detector. First, G-factors of a 3"${\Phi}X3$" NaI(Tl) detector mounted to a EFRD 3300, which means the environmental radiation monitor, in Korea Atomic Energy Research Institute (KAERI) were calculated for several directions of incident photons through the MCNP modeling, and the optimum G-factor applicable to that monitor was then determined by comparing the results both the energy band method and the G-factor method. The results for these spectrometric determinations were also compared with the dose rate from a HPIC radiation monitor around a EFRD 3300. The measured value at the EFRD 3300 based on a 3"${\Phi}X3$" NaI(Tl) detector was $7.7{\mu}R/h$ and its difference was shown about $3{\mu}R/h$, when compared with the results from a HPIC radiation moditor. Since a HPIC is known to be able to measure cosmic rays with the relatively high energy, the difference between them was caused by cosmic rays which were not detected in a 3"${\Phi}X3$" NaI(Tl) detector.

Analysis of Future Geoscience and Mineral Resources Technologies in Korea and Japan over the Next 30 Years (향후 30년의 장기적 관점으로 한국과 일본의 미래 지질자원기술 분석)

  • Ahn, Eun-Young
    • Economic and Environmental Geology
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    • v.50 no.5
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    • pp.415-422
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    • 2017
  • This study focuses on the sustainable development and intelligence information society, analyzing the results of science and technology forecasts from Korea and Japan for 2040-2050. Future geological environment and disaster technologies are presented, such as base geology, geophysical geological disaster, weather adjustment, $CO_2$ reduction, environmental disaster, and smart ecocity developments. For the future technologies in energy and resources technology, space resources development and nuclear fusion will be realized by 2040 and 2050. Moreover, new material and resource technologies will be applied to replace existing energy and mineral resources by 2040. Japan has introduced intelligent information viewpoints and presented new technologies.

Preparation of polymeric composites for surface contamination measurement in order to characterize nuclear facilities decommissioning (원자력시설 해체 시 특성평가를 위한 표면오염 탐지 이중구조 고분자 복합체의 제조)

  • 한명진;서범경;우주희;이근우
    • Proceedings of the Korean Radioactive Waste Society Conference
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    • 2004.06a
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    • pp.97-104
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    • 2004
  • Double-layered polysulfone composite films, containing cerium activated yttrium silicate (CAYS) as a flour, were prepared from double casting of two polymeric solutions, and their morphology and physical strength were superior to those of single-layered composites. The prepared polymeric films consist of a dense bottom layer and a CAYS-holding top layer. The former is made of coagulating the polysulfone and methylene chloride binary solution and works as a supporter to improve the composite's physical strength, while the latter holding the inorganic fluor plays a role as an active site to detect the radioactive contamination. The prepared films revealed two distinguished, but tightly attached, double layers, their attachment being identified by morphology of the interface between two layers. As prepared by water immersion coagulation, the films have highly developed macropores, compared with a dense structure in the film prepared by evaporation. In the radionuclide detection test of the CAYS-impregnated composites, the films have reliable detection capacity at a radionuclide spotting test. The double-layered composites with the dense support layer show a better stability in holding the radionuclides spotted on the surface as well as an improvement in physical strength, compared with the single-layer composites having shortcomings such as being too porous or being brittle.

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Feasibility about the Direct Measurement of 226Ra Using the Gamma-Ray Spectrometry (감마분광분석을 이용한 226Ra의 직접 측정방법에 대한 적용성 평가)

  • Ji, Young-Yong;Chung, Kun Ho;Lim, Jong-Myoung;Kim, Change-Jong;Jang, Mee;Kang, Mun Ja;Park, Sang Tae;Woo, Zuhee;Koo, Boncheol;Seo, Bokyun
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.12 no.2
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    • pp.97-105
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    • 2014
  • In the case of the direct measurement of $^{226}Ra$ using a HPGe gamma-ray spectrometer, the interference between gammarays with 186.21 keV of $^{226}Ra$ and 185.7 keV of $^{235}U$ should be corrected to calculate the net peak area in the energy spectrum. In general, it is very difficult to conduct peaks stripping with difference of about 0.5 keV, although a HPGe with the superior resolution is applied and the maximum channels is applied to the spectrometer. In this study, several interference correction techniques in the direct measurement were surveyed to evaluate the feasibility for the measurement of $^{226}Ra$ using the gamma-ray spectrometery. Applying the interference corrections to the analysis of raw materials and by-products, the method validation for the direct measurement of $^{226}Ra$ was conducted by evaluating the measurement uncertainty, linearity, and range. As a result, the optimum method of the interference correction was selected by comparing with the indirect measurement of which progenies of $^{226}Ra$, such as $^{214}Pb$ and $^{214}Bi$, were analyzed in the secular equilibrium state.

Characteristic of Precipitated Metal Carbonate for Carbon Dioxide Conversion Using Various Concentrations of Simulated Seawater Solution (해수 농축수 내 금속 이온 농도에 따른 이산화탄소 전환 생성물의 특성연구)

  • Choi, Eunji;Kang, Dongwoo;Yoo, Yunsung;Park, Jinwon;Huh, Il-sang
    • Korean Chemical Engineering Research
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    • v.57 no.4
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    • pp.539-546
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    • 2019
  • Global warming has mentioned as one of the international problems and these researches have conducted. Carbon Capture, Utilization and Storage (CCUS) technology has improved due to increasing importance of reducing emission of carbon dioxide. Among of various CCUS technologies, mineral carbonation can converted $CO_2$ into high-cost materials with low energy. Existing researches has been used ions extracted solid wastes for mineral carbonation but the procedure is complicated. However, the procedure using seawater is simple because it contained high concentration of metal cation. This research is a basic study using seawater-based wastewater for mineral carbonation. 3 M Monoethanolamine (MEA) was used as $CO_2$ absorbent. Making various concentrations of seawater solution, simulated seawater powder was used. Precipitated metal carbonate salts were produced by mixing seawater solutions and $rich-CO_2$ absorbent solution. They were analyzed by X-ray Diffraction (XRD), Scanning Electron Microscope (SEM), and Thermogravimetric Analysis (TGA) and studied characteristic of producing precipitated metal carbonate and possibility of reusing absorbent.

Multi-stage Compression Molding Technology of Fast Curing CF/Epoxy Prepreg (속경화용 탄소섬유/에폭시 프리프레그의 다단 압축 성형기술)

  • Kwak, Seong-Hun;Mun, Ji-Hun;Hong, Sang-Hwui;Kwon, Soon-Deok;Kim, Byung-Ha;Kim, Tae-Yong
    • Composites Research
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    • v.34 no.5
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    • pp.269-276
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    • 2021
  • PCM (Prepreg Compression Molding) process is a high-speed molding technology that can manufacture high-quality CFRP (Carbon Fiber Reinforced Plastic) parts. Compared to the autoclave process, it generates less waste and can significantly reduce cycle time, so various studies are being conducted in the aerospace and automobile industries. In this study, in order to improve the quality of the PCM process, a molding method was developed to increase the compression pressure of the press step by step according to the curing behavior of the prepreg. It was confirmed that this multi-stage compression molding technology is a good means to produce high-quality CFRP products and shorten cycle times. And, the laminated prepreg at room temperature was immediately put into the mold and preheated and molded at the same time, so that it could be molded without a separate preheating process. In addition, as a result of applying the same process conditions optimized for flat plate molding to three-dimensional shapes, a product similar to a flat plate in appearance could be made without the process of establishing process conditions.

감귤 부산물을 급여한 제주 재래돼지의 영양성분 및 기호성

  • Mun, Yun-Hui;Jeong, In-Cheol
    • Proceedings of the Korean Society for Food Science of Animal Resources Conference
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    • 2006.05a
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    • pp.71-76
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    • 2006
  • 본 연구는 제주도에서 폐기되고 있는 밀감 부산물을 돼지에게 급여하여 폐기물의 이용과 기능성 돈육의 생산을 위하여 실시하였다. 돼지는 밀감 부산물을 급여하지 않은 등심육($JPN-T_0$) 및 육성기에 8% 급여한 후 비육기에 15% 급여한 등심육($JPN-T_1$)을 대상으로 여러 가지 영양성분 분석과 관능검사를 실시한 결과 수분, 조단백질, 조지방, 조회분, 열량 및 콜레스테롤 함량은 시료들 사이 에 차이가 없었다. 무기질은 칼륨, 인, 나트륨, 마그네슘 및 칼슘의 순으로 함유되어 있으며, 칼슘의 경우 대조구가 유의하게 높았고, 다른 무기질들은 유의한 차이가 없었다. 그리고 비타민 $B_1$$B_2$의 함량도 감귤 부산물을 첨가한 것과 하지 않은 돈육 사이에 유의한 차이가 없었다. 구성아미노산의 총량은 $JPN-T_0$가 13.57%이고, $JPN-T_1$이 14.80%였다. 그리고 glutamic acid, aspartic acid, lysine 및 leucine가 많이 함유되어 있었다. 유리아미노산 총량은 대조구와 감귤 부산물 급여구 사이에 유의한 차이가 없었으나, L-valine과 L-lysine은 감귤 부산물 급여구가 유의하게 낮았다(p<0.05). 대조구와 감귤 부산물 급여구에서 포화지방산은 palmitic acid와 stearic acid가 많았으며, 불포화지방산은 oleic acid와 linoleic acid가 많이 함유되어 있었다. 생육의 색깔은 감귤 부산물을 급여하지 않은 등심육이 유의하게 높았다(p<0.05). 가열육의 기호성 중에서 향기는 $JPN-T_0$$JPN-T_1$보다 유의하게 높았으나(p<0.05), 맛, 연도, 다즙성 및 전체적인 기호성은 유의한 차이가 없었다.자체를 악하다고 볼 수 없고 더구나 구원을 이 세상에서의 이탈로 볼 수 없다. 진정한 구원이란 원래 하나님이 보시기에 아름다웠던 그 세상으로의 회복을 포함한다. 이런 면에서 하나님 주권 신앙 하에서 구원이란 전 인격적인 구원, 전 우주적인 구원이 된다. 그렇기 때문에 성도는 세상의 삶과 학문, 예술, 정치, 경제, 사회를 포함한 모든 분야를 하나님의 뜻 가운데서 그 원래의 목적에 부합할 수 있도록 회복시키는 일에 적극 참여해야 한다.자체가 이를 주도하기는 사실 어려움이 있다. 그리고 대형유통점이 영업행위를 영업시간제한에서부터 출점제한에 이르기까지 규제하는 건은 심사숙고하여야 한다. 대형유통점이 국가경제 및 지역사회에 미치는 영향이 부정적인가 긍정적인가에 대해 국내외 학계와 업계에서 여전히 많은 논란이 있기 때문이다. 정부와 지자체에 의한 시장개입은 반드시 필요한 경우에 한해 합당한 방법에 의해 이루어져야 한다. 대형유통점에 대한 규제는 지역사회에 미치는 영향을 다면적으로 평가한 결과에 근거하여 이루어져야 할 것이다. 대부분의 지자체는 체계적인 평가시스템과 객관적인 통계 자료를 갖고 있지 못한 실정이다. 향후 가장 시급한 과제는 시장개방 이후 지난 10년간 대형유통점이 지역사회에 미친 영향에 관한 광범위한 통계자료를 수집하고 이를 체계적으로 분석하여 정책방향을 올바르게 설정하는 것이라 할 수 있다.i와 K. pneumoniae가 존재하며 확산 중임을 시사한다. 앞으로 CTX-M형 ESBL의 만연과 변종 CTX-M형 ESBL의 출연을 감시하기 위한 정기적인 연구와 조사가 필요한 것으로 생각한다., A2-1, B1-1, B2-1의 경우, 강우 일수 감소 이전과 연 유출량 변화는 거의 없었으나, 유사량과 영양물질 부하량은 다소 증가하는 것으로 나타났고 연강우일수를 약20일 감소시킨 A1-2, A2-2, B1-2, B2-2의 경우는 강우일수를 감소시키기 이전에 비해 유출량이 <

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