• Title/Summary/Keyword: 저장 조건

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사용후연료 저장용기 캐니스터의 낙하평가

  • 서기석;신동필;박성원;정성환;이흥영
    • Proceedings of the Korean Radioactive Waste Society Conference
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    • 2004.06a
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    • pp.350-350
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    • 2004
  • 국내 사용후연료는 중간저장시설 확보가 지연됨에 따라 점차 각 발전소의 사용후연료 저장조가 포화상태에 이르고 있다. 국가정책에 따른 사용후연료 중간저장시설의 운영이 시작되는 시점까지 발전소에서 사용후연료 저장용기가 하나의 대안으로 고려될 수 있다. 경수로 사용후연료의 저장용기의 구조설계는 취급사고의 한 형태로서 낙하조건에 대한 안전성을 요구하고 있다. 경수로 사용후연료 24 다발을 적재하는 캐니스터는 콘크리트 외부용기(overpack)의 상부로부터 하향 방향으로 삽입된다.(중략)

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Storage characteristics of watermelon before and after removing the T-shaped stalk (수박의 꼭지 제거여부에 따른 저장성)

  • Kim, Nak-Ku;Chang, Young-Ho;Yu, Su-Pil;Ha, Ki-Jeong;Je, Hee-Jeong;Hong, Kwang-Pyo;Lee, Sang-Dae
    • Food Science and Preservation
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    • v.22 no.2
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    • pp.159-166
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    • 2015
  • This study was carried out to compare the storage characteristics of watermelon (Citrullus lanatus) before and after removing the T-shaped stalk. For the investigation of the physiochemical properties of the watermelo, the watermelaon was stored at room temperature and $7^{\circ}C$, respectively. The average weight of the watermelon (7.8 kg) decreased by 0.6~0.7% at $7^{\circ}C$ and by 1.9~2% at room temperature during the storage period of 30 days. The hardness of watermelon reduced from 755 g to 542~549 g at room temperature for 30 days. However, the existence of T-shape stalk did not significantly affect on their weight and hardness. In addition, the pH, total acid content, and inner moisture of the watermelon were not significantly changed during the storage periods while the soluble solid at room temperature was significantly decreased from $11.3^{\circ}Brix$ to $9.3^{\circ}Brix$ after 30 days of storage. The internal redness of the watermelon decreased from 36.7 to 31.7~33.6. The total amount of its free sugar was increased from the original amount (8,133 mg/100 g) and then decreased. However, the stalk did not significantly affect on the amount of total free sugar under the same storage condition, too. Thus, there was no significant difference between the results of leaving the T-shaped stalk and removing it after harvesting the watermelon.

Changes in Functional Constituents and Stability of Green Tea Beverage during Different Storing Conditions (저장조건에 따른 녹차음료의 기능성성분 변화 및 안정성)

  • Ko Won-Jun;Ko Kyung-Soo;Kim Yong-Deog;Jeong Kwan-Woo;Lee Sang-Hyup;Koh Jeong-Sam
    • Food Science and Preservation
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    • v.13 no.4
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    • pp.421-426
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    • 2006
  • Preservation stability of the extract from dried green tea produced in Jeju, extracted at $55^{\circ}C$ for 15 min and bottled in PET container after filtration and then settled at $4^{\circ}C$, indoor at room temperature and outdoor, respectively, was estimated. Color L-value was almost constant but color of the extract became darkened during storage, especially in indoor storage. Main catechins of green tea extract were (-)-epigallocatechin, (-)-epigallocatechin gallate, epicatechin, (+)-catechin, epicatechin gallate in order, and the content of epigallocatechin was 53.8%. Nevertheless total catechin content was not changed in cold storage, and $4.7\sim10%$ of total catechins were reduced in outdoor or indoor storage after 14 weeks. Caffeine content were increased but total polyphenols were not changed largely during storage. Election donating abilities (EDA) showed more than 60% without influence of storage conditions and periods. Nitrite scavenging abilities (NSA) showed more than 90% at pH 1.2, but those were decreased gradually as pH increased, and then disappeared at pH 6.0. Color, polyphenols, antioxidant activities of extract were not so changed for more than 3 months. Microbial growth was not shown during same periods, due to heat treatment of the extracts at $95^{\circ}C$ for 10 min.

Changes in Physicochemical Properties of Rice Starch from Rice Stored at Different Conditions (저장조건에 따른 쌀전분의 이화학적 성질 변화)

  • Ko, Yong-Duck;Choi, Ok-Ja;Park, Seok-Kyu;Ha, Hee-Suk;Sung, Nack-Kie
    • Korean Journal of Food Science and Technology
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    • v.27 no.3
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    • pp.306-312
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    • 1995
  • In order to know properties in rice starch during storage of rice, rice starch from stored rice(stored at $5^{\circ}C$, R.H. 65% and $30^{\circ}C$, R.H. 85%, for 16 weeks) used in this experiment. Water binding capacity of rice starch increased for 8 weeks, and then it decreased. As the storage period took longer, swelling power and solubility, optical transmittance, blue value, total amylose content and soluble amylose content decreased. For the same periods, changes in rice starch from stored rice$(30^{\circ}C$, R.H. 85%) were made more than those in rice starch at $5^{\circ}C$, R.H. 65%. The granule shape of rice starch, irrespective of storage periods and conditions, didn't make a significant difference. The relative crystallinity of the rice starch by X-ray diffraction didn't distinctly changed till the second week. But, at the fourth week, that by X-ray diffraction significantly decreased, and then slightly decreased. As the storage period took longer, gelatinization temperature, melting temperature and melting enthalpy measured by DSC got higher, but gelatinization enthalpy got lower. For the same storage period, gelatinization temperature, melting temperature, gelatinization enthalpy and melting enthalpy of rice starch stored at $30^{\circ}C$, R.H. 85% made changes more than those of rice starch stored at $5^{\circ}C$, R.H. 65% did.

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사용후핵연료 중간저장 시설의 사고시 피복관의 산화 거동 연구

  • 유길성;김건식;민덕기;노성기;김은가
    • Proceedings of the Korean Nuclear Society Conference
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    • 1995.05b
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    • pp.721-726
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    • 1995
  • 사용후핵연료 중간저장 시설의 누수사고시 예상되는 SFLFL 컴퓨터 코드 분석 결과에 따른 실제 피복관의 산화시험 결과 저장용기 밑바닥 세가지 구멍은 크긴 조건들에 대히 환기회수가 시간당 0회인 경우는 사고후 48시간 경과시 매우 심각한 산화가 예상되며, 나머지 조건의 경우에는 48시간 산화 후 최대 산화량이 90mg/dm$^2$으로 시설의 누수사고시 산화막에 의한 영향은 거의 무시 할 수 있는 것으로 나타난다. 9가지의 시험조건중 안전성은 구멍의 크기가 7.62cm, 환기수가 시간당 2회인 경우가 가장 놓으며. 두번째는 구멍의 크기가 5.08cm, 시간당 환기수 2회의 경우였다. 같은 환기회수의 경우 구멍의 크기가 5.08과 7.62cm인 경우는 비슷하게 나타나지만 2.54와 5.08cm의 경우는 큰 차이를 보인다. 여기에서 수행된 시험은 미조사, 미전처리 시편을 사용한 것이므로 실제로 조사 및 로내 산화막이 입혀진 시편에 대한 추후 시험이 요구된다.

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Sensitivity Analysis of Depletion Parameters for Heat Load Evaluation of PWR Spent Fuel Storage Pool (경수로 사용후핵연료 저장조 열부하 평가를 위한 연소조건 인자 민감도 분석)

  • Kim, In-Young;Lee, Un-Chul
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.9 no.4
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    • pp.237-245
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    • 2011
  • As necessity of safety re-evaluation for spent fuel storage facility has emphasized after the Fukushima accident, accuracy improvement of heat load evaluation has become more important to acquire reliable thermal-hydraulic evaluation results. As groundwork, parametric and sensitivity analyses of various storage conditions for Kori Unit 4 spent fuel storage pool and spent fuel depletion parameters such as axial burnup effect, operation history, and specific heat are conducted using ORIGEN2 code. According to heat load evaluation and parametric sensitivity analyses, decay heat of last discharged fuel comprises maximum 80.42% of total heat load of storage facility and there is a negative correlation between effect of depletion parameters and cooling period. It is determined that specific heat is most influential parameter and operation history is secondly influential parameter. And decay heat of just discharged fuel is varied from 0.34 to 1.66 times of average value and decay heat of 1 year cooled fuel is varied from 0.55 to 1.37 times of average value in accordance with change of specific power. Namely depletion parameters can cause large variation in decay heat calculation of short-term cooled fuel. Therefore application of real operation data instead of user selection value is needed to improve evaluation accuracy. It is expected that these results could be used to improve accuracy of heat load assessment and evaluate uncertainty of calculated heat load.

Change in the Physicochemical Properties of Dolsan Leaf Mustard under Salting Conditions (절임조건에 따른 돌산갓의 이화학적 특성 변화)

  • Bae, Sang-Ok;Wi, Sung-Dol;Lim, Hyun-Soo;Choi, Myeong-Rak
    • Food Science and Preservation
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    • v.18 no.4
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    • pp.502-507
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    • 2011
  • To investigate the optimal salting conditions, the physicochemical properties of Dolsan leaf mustard were compared under various salting times and using various washing methods and storage temperatures at 10% saline. On the other hand, the cell number of lactic-acid bacteria in Dolsan leaf mustard salted under the optimal conditions was also examined during the 50-day storage. The results of the sensory evaluation of the crispness value of the Dolsan leaf mustard treated with stepwise washing after 8h salting showed the optimal conditions for long-term preservation. The pH of the salted Dolsan leaf mustard decreased with the increase in the lactic-acid bacteria during the storage at $4^{\circ}C$. The cutting energy slowly increased during the storage, but the cutting energy of the salted Dolsan leaf mustard treated with stepwise washing remained at the initial values. The color of the salted Dolsan leaf mustard did not change during 40-day storage, but the mustard turned brown after 50-day storage, for which reason it could not be made into Dolsan leaf mustard kimchi. These results could be recommended as the optimal salting conditions and storage time of salted Dolsan leaf mustard for making kimchi.

Effect of storage temperature, period, and sawdust addition on the biochemical methane potential of cattle manure (우분의 저장온도, 저장기간, 톱밥의 혼합에 따른 메탄잠재량 변화)

  • Im, Seongwon;Kim, Sangmi;Kim, Hyu hyoung;Kim, Dong-Hoon
    • Journal of the Korea Organic Resources Recycling Association
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    • v.29 no.1
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    • pp.29-36
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    • 2021
  • In spite of the highest energy potential among all domestic organic solid wastes. the research on biogas production from cattle manure is limited. In particular, effects of organic content degradation and sawdust addition during storage on biomethane potential have never been investigated. In the present work, we investigated the change of organic content during storage of cattle manure under different temperatures (20℃ and 30℃), and its impact on biomethane potential and odor emissions. 90 days of investigation results showed that 10% of organics in terms of VS and COD were degraded at 20℃ during storage, while 30% were degraded at 30℃. This result impacted on biomethane potential, while 10-13% and 24% reduction were observed from beef and dairy cattle manure, respectively. The temperature also affected on CH4 and odor emissions during storage by 3.3-3.8 times and 29 times. The effect of sawdust on lowering down biomethane potential was found to be substantial, reducing 61-75% compared to the control.

A Quantitative Analysis of Groundwater Flow into Underground Storage Caverns (지하저장공동의 지하수 유입량에 관한 정량적 분석)

  • Chung, Il-Moon;Lee, Jeongwoo;Cho, Woncheol
    • Proceedings of the Korea Water Resources Association Conference
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    • 2004.05b
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    • pp.1062-1066
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    • 2004
  • 암반 내에 공동을 굴착하여 LPG 혹은 원유를 저장하는 경우 공동에서의 지하수 유입량은 공동상부의 수압과 공동내의 가스압과의 관계를 파악할 수 있는 정량적인 지표가 된다. 공동내의 유입량은 되도록 일정하게 유지되는 것이 굴착등의 시공단계와 공동 운영 및 유지관리면에서 유리하며, 유입량의 급증 혹은 급감이 일어나는 경우는 그 원인을 조기에 규명하여야 한다. 이를 위해서는 지하수위, 가스저장압, 수막공 주입압 등에 따른 공동주변의 유동장 해석, 공동내로의 지하수 유입량 해석을 실시해야 한다. 지하저장공동의 유입량 해석에 있어서는 공동의 정확한 형상을 반영하기 위해서 유한요소법이 보편적으로 사유되어 왔으나 한번 설정한 유한요소망으로부터 공동의 설계요소를 변경하는 작업은 수원하지 않아 설계전단계에서 공동 및 수막 시설의 다양한 배치에 따른 모의를 수행하는데는 다소 무리가 있다. 이러한 불편함은 경계부의 형상과 조건만으로 내부점에서의 미지변수 계산을 효과적으로 수행할 수 있는 경계요소법을 도입함으로써 극복할 수 있다. 따라서 본 연구에서는 지하공동으로 배수되는 유입량 산정을 위해 경계요소법을 근간으로 한 2차원 지하수 흐름모형을 구성하였고, 이를 지하저장공동이 위치한 A기지에 적용하여 상부경계조건인 지하수위의 변화, 수막공 주입압 등에 따른 공동내의 유입량과 공동저장압과의 관계를 정량적으로 분석하였다. 분석 결과를 지하저장공동의 운영 및 유지관리에 활용될 수 있도록 수식화하여 제시하였다.

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Changes of Storability and Quality Characteristics of 'Autumn Sense' Hardy Kiwifruit According to Ethylene Treatment and Storage Condition (에틸렌 처리와 저장조건에 따른 '오텀센스' 다래의 저장성 및 품질특성 변화)

  • Oh, Sung-Il;Kim, Chul Woo;Kim, Mahn-Jo
    • Journal of Korean Society of Forest Science
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    • v.103 no.3
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    • pp.368-374
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    • 2014
  • This study was investigated the changes of storability and quality characteristics of 'Autumn Sense' hardy kiwifruit according to ethylene treatment and storage condition. In the results of investigation of changes in hardy kiwifruit quality during storage period, hardness of ethylene treated hardy kiwifruit during 48 and 96 hours was rapidly decreased, but soluble solid content was rapidly increased with the passing of storage period in all treatment groups. The total acid was estimated from 0.7 to 1.4% with storage period in all treatment groups. In the results of investigation of the weight loss rate, ethylene treated hardy kiwifruit during 48 hours was the highest 30.9% in storage at $20^{\circ}C$ and lowest 5.9% in storage at $2^{\circ}C$ with a relative air humidity of about 90% during storage at 24 days. Ethylene treated hardy kiwifruit during 96 hours was decrease 29.4% in storage at $20^{\circ}C$, 20.7% in storage at $4^{\circ}C$, 12.1% in storage at $2^{\circ}C$, and 6.0% in storage at $2^{\circ}C$ with a relative air humidity of about 90% during storage at 22 days. The taste of hardy kiwifruit during storage was reduced to increase in all treatment groups. Particularly, storage at $20^{\circ}C$ was rapidly reduced to increase in the early storage and storage at $2^{\circ}C$ with a relative air humidity of about 90% was decrease after storage at 18 days. The rotten rate during storage was increased in all treatment groups, storage at $20^{\circ}C$ was after storage at 2 days and storage at $2^{\circ}C$ with a relative air humidity of about 90% was rapidly increased after storage at 16 days. Thus, it can be recommended that storage at $2^{\circ}C$ with a relative air humidity of about 90% is good to maintain quality. Also, we will decide optimal storage condition and after-ripening time of 'Autumn Sense' hardy kiwifruit.