• 제목/요약/키워드: Nuclear membrane

검색결과 511건 처리시간 0.028초

미시적 재료모델을 사용한 원전 격납건물 벽체 요소의 구조거동 분석 (On the investigation of structural behaviour of nuclear containment building wall element using microscopic material model)

  • 이상진;이홍표;서정문
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2000년도 가을 학술발표회논문집
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    • pp.217-221
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    • 2000
  • Nonlinear stress analysis of nuclear containment building wall element is carried out using microscopic material model. The present study mainly focuses on the finite element analysis of the nuclear containment building wall element under biaxial tensile stresses and it evaluates the perfomance of adopted microscopic material model in the membrane energy dominant situation. From the numerical analysis, the adopted material model peforms well and has a good agreement with experiment result. Finally, the result of present study can be severed as a benchmark test when concrete material model is in need of evaluation.

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원자력 발전소의 해수전해설비 폐수소를 활용한 PEM 연료전지 발전 시스템에 관한 연구 (A study on the power plant system combined with PEM fuel cell and the wasted hydrogen from the sea water electrolyzer of nuclear power plants)

  • 최종원;이주형;차석원;김민수
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2010년도 춘계학술대회 초록집
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    • pp.124.2-124.2
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    • 2010
  • Generally, a coolant of the nuclear power plant is manufactured by electrolyzing the sea water near the plant for making the sodium hypochlorite(NaOCl), which is used for sterilizing the bacteria and the shellfishes sticking to the drains or the pumps at the outlet of the cooling system due to $8-10^{\circ}C$ warmer temperature than the inlet sea water. During manufacturing the sodium hypochlorite, the hydrogen with the high purity is also produced at the anode side of the electrolyzer. This paper describes a novel power plant system combined with the polymer electrolyte membrane(PEM) fuel cell, the wasted hydrogen from the sea water electrolyzer and the wasted heat of the nuclear power plant. The present status over the exhausted hydrogen at twenty nuclear power plants in Korea was investigated in this study, from which an available power generation is estimated. Furthermore, the economic feasibility of the PEM fuel cell power plant is also evaluated by a current regulations over the power production and exchange using a renewable energy shown in Korea Power Exchange(KRX).

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아프리카 왕달팽이 (Achatina fulica) 난모세포 성숙에 관한 미세구조 (Ultrastructural Study on the Maturation of Oocyte in the African Giant Snail, Achatina fulica)

  • 장남섭;한종민
    • Applied Microscopy
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    • 제30권4호
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    • pp.367-376
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    • 2000
  • 아프리카 왕달팽이 (Achatina fulica)의 난모세포 성숙과정을 전자현미경을 통해 관찰한 결과 3단계 과정으로 나눌 수 있었다. 제1기 난모세포는 그 크기가 $220\times400{\mu}m$정도의 작은 타원형의 세포로서 밝은 핵질속에 2개의 인이 존재하였다. 세포질에는 많은 수의 사립체와 조면소포체 그리고 리보솜이 있었으며 난황과립들은 관찰되지 많았다. 제2기 난모세포의 핵은 세포질의 용적에 비해 비교적크고 한 개의 인을 소지하고 있었다. 내, 외 이중막으로 구성된 핵막에는 많은 핵공이 관찰되고 이를 통해 물질 이동 현상이 관찰되었다. 세포질에는 많은 수의 사립체, 골지체 그리고 지방성 난황과립들이 출현하였으며, 대, 소형의 공포(직경, $0.8\sim3.0{\mu}m$)들 속에는 단백질성난황 과립들이 형성, 성숙되고 있었다. 제3기 난모세포는 핵에 비해 핵소체의 크기가 증대되었고 핵공을 통한 물질이동현상은 관찰되지 않았다. 세포질 속에는 성숙된 단백질성난황과립과 지방성난황과 립들로 가득 차 있었으며, 난막의 주위에는 미세융모가 발달해 있었다.

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중.저준위 방사성폐기물 유리화설비에서 금속필터 적용성평가 (Performance Evaluation of Sintered Metal Filter in LILW Vitrification Facility)

  • 박승철;김병렬;황태원
    • 에너지공학
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    • 제15권3호
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    • pp.146-153
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    • 2006
  • 중 저준위 방사성폐기물 유리화 공정에서 발생되는 분진을 제거하기 위하여 저온용융로 후단에 금속필터를 장착하여 성능시험 및 필터 적용 평가를 실시하였다. 실험결과 기존의 고온세라믹필터와 유사한 차압특성을 보였으며, 유량 $110Nm^{3}/hr$ 기준으로, 필터 자체에 의한 압력손실은 $25mmH_{2}O$, 분진 잔류층에 의한 압력손실은 $67mmH_{2}O$ 정도였다. 따라서 기저차압은 $92mmH_{2}O$ 정도임을 확인할 수 있었다. 또한 SEM-EDS 분석결과 대부분의 차압은 멤브레인층의 표면에서 발생된 것으로 판단되며, 열화현상에 의한 부식문제등도 발견되지 않았다. 따라서 금속필터의 경우 유리화설비에 적용 가능한지를 분석하고, 장기시험을 통한 충분한 검증이 필요할 것으로 판단된다.

객담과 기관지세척액에서 폐 샘암종과 유사한 병변의 세포소견 분석 (Cytologic Evaluation of Adenocarcinoma and its Mimics in Sputum and Bronchial Washings)

  • 박인서;최석진;김루시아;한지영;김준미;박정애;주영채
    • 대한세포병리학회지
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    • 제18권1호
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    • pp.36-45
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    • 2007
  • Objective : To identify key cytologic features for diagnosis of adenocarcinoma and morphologic differentiation from reactive/reparative respiratory epithelium. Study Design : The cytomorphologic features of 145 pulmonary cytology specimens (sputum and bronchial washing), which included 117 histologically proven adenocarcinomas and 28 non-neoplastic lesions, cytologically diagnosed as atypia and suspicious for malignancy (adenocarcinoma) were reviewed retrospectively. We analyzed 11 morphologic criteria in pulmonary cytologic specimens. Results: Over 110 of 117 cases of adenocarcinomas revealed nuclear membrane irregularities, non-cohesive cells, single atypical cells, moderate to markedly enlarged nuclei and an increased nuclear/cytoplasmic (N/C) ratio. Chromatin clearing, chromatin heterogeneity and hyperchromasia were seen in 102, 99 and 97 cases, respectively. All 28 cases involving non-neoplastic lesions revealed hyperplastic reactive pneumocytes, hyperplastic reactive bronchial epithelium, or degenerating macrophages. The non-neoplastic lesions revealed a small number of atypical cell clusters and paucity or absence of atypical single cells. Conclusion : The most important morphologic features for diagnosis of adenocarcinoma are nuclear membrane irregularities, non-cohesive cells, single atypical cell, moderate to markedly enlarged nuclei and increased N/C ratio. Chromatin clearing, chromatin heterogeneity and hyperchromasia were also helpful features, while pleomorphism and prominent nucleoli were less valuable.

공기부유진내(空氣浮游塵內)의 Radon 붕괴생성물(崩壞生成物)의 농도측정(濃度測定) (Measurement of Radon Daughters in Airborne Dust)

  • 김필수;민덕기;노성기
    • Journal of Radiation Protection and Research
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    • 제2권1호
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    • pp.9-16
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    • 1977
  • 공기부유진내(空氣浮游塵內)에 존재(存在)하는 라돈 붕괴생성물(崩壞生成物) 즉(卽) RaA, RaB및 RaC의 간단(簡單)한 농도측정법(濃度測定法)을 확립(確立)하였다. 이것은 단일집진장치(單一集塵裝置)로 membrane 여과지(濾過紙)(평균(平均) pore size=$0.8{\mu}m$)에 채취(採取)한 시료(試料)의 전(全)알파 방사능(放射能)을 시차별(時差別)로 측정(測定)하므로서 농도(濃度)를 결정(決定)하는 방법(方法)이다. 일연(一聯)의 예비실험(豫備實驗)으로써 이 방법(方法)을 이용(利用)하여 한국원자력연구소(韓國原子力硏究所) 구내(構內)에서 라돈 붕괴생성물(崩壞生成物)의 시간적(時間的) 농도변화(濃度變化)를 측정(測定)하였다. 이들 농도(濃度)의 시간적(時間的) 변화(變化)는 심(甚)하였는데 대개(大槪)의 경우(境遇) 최고치(最高値)는 대기(大氣)의 밀도(密度)가 비교적(比較的) 높은 아침에 나타났고 최고치(最高値)는 기(其) 반대(反對)인 오후(午後)에 나타났다.

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New Family of Monoglucosylglyceride Diacyl Glycerol Lipids Containing Very Long Chain bifunctional Acyl Chains in Sarcina ventriculi

  • Jung, Seun-Ho;Chi, Yong-Hoon;Chang, Yoon-Seok;Yi, Dong-Heui;Kwon, Tae-Jong;Hollingsworth, Rawle I.
    • Journal of Microbiology and Biotechnology
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    • 제10권3호
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    • pp.386-393
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    • 2000
  • Recent research on the fatty acyl chains in the membrane lipids in Sarcina ventriculi has shown that unusually long chain bifunctional fatty acyl components are the major components of the total lipid. However, these studies did not yield any information on the complete structures of the lipid species containing these fatty acids. In this study, the structures of a new family of glucolipids containing bifunctional acyl chains are described. These structures were determined using NMR(Nuclear Magnetic Resonance) Spectroscopy, GC (Gas Chromatography)/MS (Mass Spectrometry), FTIR (Fourier Transform Infrared) spectroscopy, and FAB (Fast Atom Bombardment) mass spectrometric studies. One of the major bifunctional acyl components of the $\alpha$-glucolipids was an $\omega$-formylmethyl ester indicating the presence of plasmalogen. The general structure of the lipid components was one in which the two head groups were separated by a membrane-spanning acyl species. One head group component is a glycerol moiety of each head group, and the other is a glyceryl clucoside. Two regular chain fatty acids, one on the glycerol moiety of each head group, are also present and meet in the middle of the membrane, roughly equidistant from each head group.

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An NMR Study on the Phase Change of Lipid Membranes by an Antimicrobial Peptide, Protegrin-1

  • Kim, Chul
    • Bulletin of the Korean Chemical Society
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    • 제31권2호
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    • pp.372-378
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    • 2010
  • Membrane disruption by an antimicrobial peptide, protegrin-1 (PG-1), was investigated by measuring the $^2H$ solid-state nuclear magnetic resonance (SSNMR) spectra of 1-palmitoyl-$d_{31}$-2-oleoyl-sn-glycero-3-phosphatidylcholine (POPC_$d_{31}$) in the mixture of PG-1 and POPC_$d_{31}$ lipids deposited on thin cover-glass plates. The experimental line shapes of anisotropic $^2H$ SSNMR spectra measured at various peptide-to-lipid (P/L) ratios were simulated reasonably by assuming the mosaic spread of bilayers containing pore structures or the coexistence of the mosaic spread of bilayers and a fast-tumbling isotropic phase. Within a few days of incubation in the hydration chamber, the pores were formed by the peptide in the POPC_$d_{31}$ and POPC_$d_{31}$/cholesterol membranes. However, the formation of the pores was not clear in the POPC_$d_{31}$/1-palmitoyl-2-oleoyl-sn-glycero-3-phosphatidylglycerol (POPG) membrane. Over a hundred days after hydration, a rapidly rotating isotropic phase increased in the POPC_$d_{31}$ and the POPC_$d_{31}$/cholesterol membranes with the higher P/L ratios, but no isotropic phase appeared in the POPC_$d_{31}$/POPG membrane. Cholesterol added in the POPC bilayer acted as a stabilizer of the pore structure and suppressed the formation of a fast-tumbling isotropic phase.

인삼(人蔘) Callus세포(細胞)의 미세구조적(微細構造的) 비교(比較) 연구(硏究) (A Comparative Study of Fine Structure of Callus Cells in Panax ginseng)

  • 이재두;이규배
    • Applied Microscopy
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    • 제8권1호
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    • pp.67-76
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    • 1978
  • A comparative investigation of fine structure of callus cells derived from tissue culture of Panax ginseng was made by electron microscope. Callus was consisted of large superficial cells and small inner zone cells derived from shoot apex tissue cultured for 16 weeks. Large superficial cells were contained the clusters of starch grains surrounded by a double plastid membrane. Especially, electron dense particles were deposited just inside and outside of plastid membrane and also deposited on mitochondria-like and endoplasmic reticulum-like structures. Crystalline body was also found in superficial cells. Small inner zone cells were characterized by presence of proplastids sheathed by short endoplasmic reticulum profiles. presence of spiral configuration of ribosomes and absence of crystalline body. Organ primordia was consisted of a dense cytoplasm and notable nucleate cells derived from nodal tissue cultured for 67 weeks. Proplastids containing starch grains and crystalline bodies were frequently observed; starch grains are of small quantity and does not form the clusters as in inner zone cells; hexagonal crystalline body itself does not have always limiting membrane. Remarkably. in a few cells of primordia, particles resembling the presumptive virus were observed mainly in condensed nuclear chromatin and also in cytoplasm, in mitochondrion-like organelle.

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Reference Electrode at Molten Salt: A Comparative Analysis of Electroceramic Membranes

  • Yoon, Seokjoo;Kang, Dokyu;Sohn, Sungjune;Park, Jaeyeong;Lee, Minho;Choi, Sungyeol
    • 방사성폐기물학회지
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    • 제18권2호
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    • pp.143-155
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    • 2020
  • A reference electrode is important for controlling electrochemical reactions. Evaluating properties such as the reduction potential of the elements is necessary to optimize the electrochemical processes in pyroprocessing, especially in a multicomponent environment. In molten chloride systems, which are widely used in pyroprocessing, a reference electrode is made by enclosing the silver wire and molten salt solution containing silver chloride into the membranes. However, owing to the high temperature of the molten salt, the choice of the membrane for the reference electrode is limited. In this study, three types of electroceramic, mullite, Pyrex, and quartz, were compared as reference electrode membranes. They are widely used in molten salt electrochemical processes. The potential measurements between the two reference electrode systems showed that the mullite membrane has potential deviations of approximately 50 mV or less at temperatures higher than 650℃, Pyrex at temperatures lower than 500℃, and quartz at temperatures higher than 800℃. Cyclic voltammograms with different membranes showed a significant potential shift when different membranes were utilized. This research demonstrated the uncertainties of potential measurement by a single membrane and the potential shift that occurs because of the use of different membranes.