• 제목/요약/키워드: C rate

검색결과 19,620건 처리시간 0.053초

토양생물반응기내 Toluene의 분해 특성 (Biodegradation Characteristics of Toluene in a Soil-Bioreactor)

  • 김철경
    • 청정기술
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    • 제8권4호
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    • pp.199-203
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    • 2002
  • 석유탄화수소의 분해능이 확인된 Pseudomonas fluorescens KCTC 1767을 이용하여 혐기 상태에서 톨루엔 분해의 최적조건을 찾기 위해서 회분식으로 pH, 회전속도, 온도를 변수로 하여 실험하였고, 토양 생물반응기에서는 연속식으로 톨루엔을 분해하는 최적의 순환유속을 찾고자 실험하였다. 온도 $15^{\circ}C$, 초기 pH 7의 회분식 실험에서 rpm에 따른 톨루엔 분해는 45시간이 경과한 후에 120rpm의 경우 잔여농도 37.4 ppm으로 62.6%의 분해율, 180 rpm의 경우 잔여농도 13.0 ppm으로 83% 분해율, 60 rpm의 경우는 불검출로 60 rpm에서 가장 좋은 결과를 보였으며, 회전속도 120rpm, 초기 pH 7에서 실시한 회분식 실험에서 톨루엔 분해는 45시간 경과후 $15^{\circ}C$에서는 잔여농도 37.4 ppm을 보였으나 $30^{\circ}C$에서는 검출이 되지 않아 대부분의 분해된 것으로 나타났다. 온도 $30^{\circ}C$, 초기 pH 7의 조건에서 탱크 내 균체량은 35 mL/min에서 0.19g/L 를 보여 최고의 성장을 보였으며, 톨루엔은 9시간이후 검출되지 않았다. 혐기상태에서 Pseudomonas fluorescens KCTC 1767를 이용하여 톨루엔을 분해하는데 회분식실험과 연속식 토양생물반응기에서의 최적조건은, 회분식의 경우 60 rpm과 온도 $30^{\circ}C$인 것으로 나타났으며, 연속식 토양 생물반응기의 경우 55mL/min, 80mL/min, 85 mL/min중 가장 낮은 유속인 55 mL/min 에서 결과가 좋았다.

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316L 스테인리스 강의 고온 저주기 피로 수명식 개발 (Development of a New LCF Life Prediction Model of 316L Stainless Steel at Elevated Temperature)

  • 홍성구;이순복
    • 대한기계학회논문집A
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    • 제26권3호
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    • pp.521-527
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    • 2002
  • In this paper, tensile behavior and low cycle fatigue behavior of 316L stainless steel which is currently favored structural material for several high temperature components such as the liquid metal cooled fast breeder reactor (LMFBR) were investigated. Research was performed at 55$0^{\circ}C$, $600^{\circ}C$ and $650^{\circ}C$ since working temperature of 316L stainless steel in a real field is from 40$0^{\circ}C$ to $650^{\circ}C$. From tensile tests performed by strain controls with $1{\times}10^{-3}/s,\; l{\times}10^{ -4}/s \;and\; 1{\times}10/^{ -5}/ s $ strain rates at each temperature, negative strain rate response (that is, strain hardening decreases as strain rate increases) and negative temperature response were observed. Strain rate effect was relatively small compared with temperature effect. LCF tests with a constant total strain amplitude were performed by strain control with a high temperature extensometer at R.T, 55$0^{\circ}C$, $600^{\circ}C$, $650^{\circ}C$ and total strain amplitudes of 0.3%~0.8% were used and test strain rates were $1{times}10^{-2} /s,\; 1{times}10^{-3} /s\; and\; 1{times}10^{-4} /s$. A new energy based LCF life prediction model which can explain the effects of temperature, strain amplitude and strain rate on fatigue life was proposed and its excellency was verified by comparing with currently used models.

견섬유에 대한 산성 Levelling 및 Milling 염료의 단일 및 혼합염색에 있어서의 염색속도에 관한 연구 (A study on the dyeing-rate in single and mixture dyeing of silk with levelling and milling acid dyes)

  • 배도규
    • 한국잠사곤충학회지
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    • 제33권1호
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    • pp.9-12
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    • 1991
  • 견섬유에 대한 산성 levelling 및 milling계 염료의 혼합염색에 있어서 그 염색특성에 관한 기초적인 자료를 얻기 위하여, C. I. Acid Orange 7과 C. I. Acid Blue 138을 사용하여, 염욕의 pH를 각각 pH 3, 4, 5, 염색온도 7$0^{\circ}C$의 조건으로 단일 및 혼합염색을 실시하여 흡착속도에 관하여 고찰했다. 1)C. I. Acid Orange 7 A)pH 3 : 염색초기에 있어서 단일염색에 비해 혼합염색을 했을 때 흡착속도가 빠르고 흡착량도 많았다. B)pH 4, 5 : 단일염색 및 혼합염색 양자간의 흡착속도 및 양에 거의 차이가 없었다. 2)C. I. Acid Blue 138 A)pH 3, 4, 5 전부 혼합염색일 때가 염색초기에 더 빠른 흡착속도와 더 많은 흡착량을 나타냈다. B)염색시간이 경과함에 따라 혼합염색과 단일염색간의 흡착속도와 흡착량의 차이가 인정되지 않았다.

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방사성옥도(放射性沃度)(I131)의 주입량(注入量)이 기니픽 갑상선(甲狀腺)에의 섭취(攝取) 및 방출률(放出率)에 미치는 영향(影響)에 관(關)한 연구(硏究) 제(第)1보(報) 방사성옥도(放射性沃度)(I131)의 주입량(注入量)이 웅(雄)기니픽 갑상선(甲狀腺)에서의 섭취(攝取) 및 방출률(放出率)에 미치는 영향(影響) (Studies on the Effects of Injected Amount of I131 in Uptake and Release Rate by Thyroid in Guinea Pigs 1. On the Influence of Injected Amount of Redioiodine-131 in Uptake and Release Rate by Thyroid in Male Guinea Pigs)

  • 정영채;심상칠;이흥식
    • 대한수의학회지
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    • 제6권1호
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    • pp.24-30
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    • 1966
  • In order to observe the effect of the injected radioactive iodine-$I^{131}$ on the uptake in thyroid of normal male guinea pigs and P.B.$I^{131}$ conversion ratio of $I^{131}$ in serum, 24 matured male guinea pigs were divided in 4 groups and $35{\mu}c$, $70{\mu}c$, $140{\mu}c$ and $280{\mu}c$ per kg of body weight respectively were injected subcutaneously. 1. The uptake rates of radioactveiodine-$I^{131}$ by external counts of thyroidal uptake reached the maximum level of uptake in 24 hours after injection. 2. As the injected amount increases, the uptake rates of maximum levels and release rate were increased. 3. Uptake rate in the removed thyroid have shown no statistical in the $35{\mu}c$ and $70{\mu}c$ groups of injected guinea pigs. 4. There was no statistical significance in $140{\mu}c$ and $280{\mu}c$ groups of injected guinea pigs. 5. P.B.$I^{131}$ conversion ratio of $I^{131}$ in serum was not in proportion to injected amounts: 61.0%(35), 70.2%(70), 75.3%(140) and 64.8%(280).

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연료 공급 및 S/C비에 따른 평판형 STR 반응기 성능 평가 (The Performance Evaluation of Plate Type STR Reactor with Variation of S/C Ratio and Fuel Supply)

  • 김헌주;허수빈;박재민;윤봉석;이도형
    • 한국수소및신에너지학회논문집
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    • 제22권2호
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    • pp.191-198
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    • 2011
  • According to the propagation of fuel cell system, the importance of that system efficiency is being magnified. Thus, the efficiency improvement of reformer which is the important factor of fuel cell system will be required. This study has been experimentally performed to evaluated the performance of plate type STR reactor. At first, we changed fuel flow rate (2, 3 and 4 l/min) in burner, and then we measured a proportion of hydrogen in produced gas through the STR reactor by G.C for evaluating the performance of plate type STR reactor in various fuel supply conditions. And we changed S/C ratio (2 and 4) and measured a proportion of hydrogen in produced gas through the STR reactor. As a results, condition at fuel flow rate 2 and 3 l/min could not be supplied amount of heat for STR sufficiently. Condition at fuel flow rate 4 l/min could supplied a heat excessively. And condition at S/C ratio 2, reaction occurred insufficiency. But condition at S/C ratio 4 was excess. From above, we found the optimum conditions that were fuel rate 3.5 l/min and S/C ratio 3.

서열과 한냉 자극에 대한 반복 국소 노출이 혈류량 및 심박수에 미치는 영향 (Effect of local heating and cooling on blood flow and heart rate.)

  • 박순자
    • 한국농촌생활과학회지
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    • 제5권1호
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    • pp.1-8
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    • 1994
  • 온랭 열 자극에 대하여 인체의 말초 혈류량과 심박수가 어떻게 반응하는가를 관찰하기 위하여 건강한 성인 여자 4명을 피험자로 실험군과 비교군으로 나누어 실험을 실시하였다. 실험군은 온랭열 자극의 단기 훈련을 12회 실시하고 비교군은 실험군의 초기와 말기 2회 실시하여 얻은 결과를 비교ㆍ검토하여 다음과 같은 결과를 얻었다. $\circled1$ 실험군에서의 손가락 혈류량의 초기 반응은 훈련 후에 민감해졌다. $\circled2$ 심박수는 냉수 노출시보다 온수 노출시 증가하였다. $\circled3$ 실험군과 비교군간에는 혈류량의 변화 형태와 심박수에 차이가 있었다. 이상에서 E-군과 C-군의 혈류량과 심박수에서 차이를 나타낸 것은 단기 훈련 효과에 의한 것으로 추정된다.

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Ni-Ti계 합금 선재의 변태온도 변화에 따른 인장변형 및 회복 특성 (Characteristics of Tensile Deformation and Shape Recovery with Transformation Temperature Change in a Ni-Ti Alloy Wire)

  • 최윤길;김미선;조우석;장우양
    • 열처리공학회지
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    • 제21권6호
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    • pp.307-313
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    • 2008
  • The tensile deformation and shape recovery behaviors were studied in Ni-Ti shape memory wires showing different transformation characteristics by annealing at $200{\sim}600^{\circ}C$. Both R phase ${\rightarrow}$ B19' martensitic transformation at lower temperature and B2 ${\rightarrow}$ R phase transformation at higher temperature occurred in the shape memory wires annealed at $200{\sim}500^{\circ}C$. Transformation temperature and heat flow of B19' martensite increase but those of R phase main almost constant even with increasing annealing temperature. In the case of wires annealed and then cooled to $20^{\circ}C$, plateau on stress-strain curves in tensile testing can be observed due to the collapse of R phase variants and the formation of deformation-induced B19' martensite. In the case of wires annealed and then cooled to $-196^{\circ}C$, however, plateau on stress-strain curves does not appear and stress increases steadily with increasing tensile deformation. Comparing shape recovery rate with cooling temperature after annealing, shape recovery rate of the wire cooled to $20^{\circ}C$ is higher than that of the wire cooled to $-196^{\circ}C$ after annealing, and maximum shape recovery rate of 95% appears in the wire annealed at $400^{\circ}C$ and then cooled to $20^{\circ}C$. $R_s$ and $R_f$ temperatures measured during shape recovery tests are higher than $A_s$ and $A_f$ temperatures measured by DSC tests even at the same annealing temperature.

겨울철 개구리 (Rana temporaria)의 $Na^{+}$이온 대사 ($Na^{+}$ Metabolism in the Frog in the Winter Time)

  • 이중우;강두희
    • The Korean Journal of Physiology
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    • 제7권1호
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    • pp.41-47
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    • 1973
  • $Na^{+}$ balance was studied in Rana temporaria, which hibenates in fresh water in the winter time. $Na^{+}$ uptake rate, skin $Na^{+}$ loss rate, urinary $Na^{+}$ loss rate and $Na^{+}-K^{+}$ adenosine triphosphatase(ATPase) were measured at two different temperatures $1{\sim}2^{\circ}C\;and\;20{\sim}24^{\circ}C$ respectively. The results obtained were as follows: 1. $Na^{+}$ uptake rates in the frog in an artificial Pond water (APW) were found to be $8.28{\pm}0.73\;and\;2.19{\pm}0.37\;{\mu}Eq/g/day\;at\;20{\sim}24^{\circ}C\;and\;1.0{\sim}2.5^{\circ}$ respectively. 2. $Na^{+}$ loss rate through the frog skin to APW were found to be $4.26{\pm}0.72\;and\;0.93{\pm}0.21\;{\mu}Eq/g/day$ at the same temperatures. 3. Mean rates of urinary $Na^{+}$ loss at $20{\sim}24^{\circ}C\;and\;3{\sim}4^{\circ}C$ were found to be $3.02{\pm}0.73\;and\;0.78{\pm}0.13\;{\mu}Eq/g/day$ respectively. 4. The activities of $Na^{+}-K^{+}$ activated ATPase of frog skin fragments were found to be $258{\pm}39.4\;and\;49.6{\pm}7.1\;{\mu}M\;Pi/g$ protein/hr at $24^{\circ}C\;and\;2^{\circ}C$ respectively. From the above results, it may be concluded that frogs can take up enough $Na^{+}$ through the skin from APW exceeding skin loss Plus urinary loss at $1{\sim}2^{\circ}C$. It is suggested that $Na^{+}$ transport across frog skin is closely related with $Na^+-K^+$ ATPase since $Q_{10}\;of\;Na^{+}$ uptake is much similar to that of the activities of $Na^{+}-K^{+}$ ATPase.

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저장조건이 딸기 “미녀봉”의 저장 중 품질 및 미생물학적 변화에 미치는 영향 (Effect of Storage Condition on the Quality and Microbiological Change of Strawberry “Minyubong” during Storage)

  • Lee, Se-Hee;Lee, Myung-Suk;Namkyu Sun;Song, Kyung-Bin
    • 한국식품저장유통학회지
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    • 제11권1호
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    • pp.7-11
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    • 2004
  • 저장조건이 딸기 “미녀봉”의 저장 중 품질 및 미생물학적 변화에 미치는 영향을 연구하기 위하여 저장 중 중량감소율, 부패율, pH 및 적정산도, 총균수 및 곰팡이와 효모 수의 변화가 측정되었다. 딸기 시료는 LDPE로 포장하여 4$^{\circ}C$와 2$0^{\circ}C$에서 각각 저장하였다. LDPE포장은 대조구에 비해 중량감소율 및 부패율을 감소시켰다. 또한 포장방법은 저장중 미생물학적 변화에 영향을 끼쳤는데 저장온도와 상관없이 대조구와 비교해서 효모와 곰팡이뿐만 아니라 총균수의 감소를 야기시켰다. 본 연구결과는 딸기 “미녀봉”의 유통기한을 고려할 때 4$^{\circ}C$에서 LDPE 포장으로 저장하는 것이 바람직하다는 것을 나타냈다.

Types of Home Meal Replacement and Determinants of Consumption in South Korea

  • Ahn, Kyeong Ah;Choe, Young Chan;Cho, Hye Bin
    • Agribusiness and Information Management
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    • 제6권2호
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    • pp.1-12
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    • 2014
  • HMR is a home-style food product designed for convenience and cooked outside the home leaving out cumbersome cooking process and consumed at home. The present paper aims to find out factors that influence the consumption of HMR by analyzing data on food consumption during the 3 years between December 2010 and November 2013. Following the classification of Costa et al. (2001), this study categorized HMR products as 3 types as follows: C1 (ready to eat), C2 (ready to heat) and C3 (ready to cook), and examined factors affecting purchase rate and per capita purchase price for each type of HMR product. The results of our analysis show that only the purchase rate of C3 products was influenced by whether the purchaser was housewife with job or not. For those who do not live together with parents, per capita purchase price for HMR was high; and the more they ate out, the higher the purchase rate of HMR was.