• 제목/요약/키워드: Concentration Ability

검색결과 1,843건 처리시간 0.032초

Water Mist Fire Suppression for Raised Subfloor Spaces

  • Kim, Woon-Hyung;Kim, James A. Milke
    • 한국화재소방학회:학술대회논문집
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    • 한국화재소방학회 1997년도 International Symposium on Fire Science and Technology
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    • pp.617-624
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    • 1997
  • Over 100 experiments have been conducted at the University of Maryland to evaluate the performance of a water mist fire suppression system for protection of an interstitial space below a raised subfloor. Experiments are conducted as part of an ongoing research effort to compare the fire suppression capabilities of various water mist system designs in a raised subfloor space. Water mist system design parameters considered in the investigation include means of actuation, concentration of water mist required for extinguishment of fires, and delivery mechanisms of water mist within close proximity to the fire. Delivery of the required concentration of water mist within close proximity to the fire is a principal factor governing the adequacy of water mist systems. Two sets of experiments have been conducted to document the performance of water mist system designs. One set is involved in documenting the concentration of water mist as a function of position within the space. The second set of experiments is concerned with the ability of water mist system designs to control fires in the space. One result of the research is the assessment of the ability of a water mist system to control fires at particular locations as a function of water mist density at that location.

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판람근(Isatis tinctoria L., 板藍根)추출물의 항산화활성 및 화장품약리활성에 관한 연구 (Study on anti-oxidant and cosmeceutical activities of Isatis tinctoria L.)

  • 김영훈;조우아;천순주;장민정;성지연;정수현;최향자;김대익;김정옥;이창언;안봉전;이진태
    • 대한본초학회지
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    • 제22권3호
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    • pp.85-91
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    • 2007
  • Objective : In this study, anti-oxidant and cosmeceutical activities of Isatis tinctoria L. extracted from water, ethanol and supercritical fluid condition were confirmed to investigate cosmeceutical activities for utilization as cosmetic ingredient. Methods: Anti-oxidant and cosmeceutical activities were investigated by using electron donating ability, xanthine oxidase, tyrosinase, astringent effect. Result : Isatis tinctoria L. extracts by supercritical fluid, water and ethanol showed good electron donating ability which were 82.7%, 62.6% and 44.8% at the concentration at 1,000ppm, respectively. Xanthine oxidase activity related with purine metabolism was inhibited by ethanol extract about 52.3% at the concentration at 1,000ppm. Tyrosinase inhibition effects, by supercritical fluid extract, ethanol extract and water extract, were 83.3%, 52.9% and 41.2% respectively at 1,000ppm. In the measurement of astringent effect, supercritical fluid extract at the concentration to 5,000ppm showed 85.7% in related activity. The water extract showed 95.9% nitrite scavenging activity at 5,000ppm. Conclusion : According to these results, it is possible that the extract of Isatis tinctoria L. can be used as a new natural material of cosmetic industry.

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Efficient aerobic denitrification in the treatment of leather industry wastewater containing high nitrogen concentration

  • Kang, Kyeong Hwan;Lee, Geon;Kim, Joong Kyun
    • Environmental Engineering Research
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    • 제20권1호
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    • pp.79-87
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    • 2015
  • To treat leather industry wastewater (LIW) containing high nitrogen concentration, eight aerobic denitrifiers were isolated from sludge existing in an LIW-treatment aeration tank. Among them, one strain named as KH8 had showed the great ability in denitrification under an aerobic condition, and it was identified as Pseudomonas aeruginosa R12. The aerobic denitrification ability of the strain KH8 was almost comparable to its anaerobic denitrification ability. In lab-scale aerobic denitrifications performed in 1-L five-neck flasks for 48 hr, denitrification efficiency was found to be much improved as the strain KH8 held a great majority in the seeded cells. From the nitrogen balance at the cell-combination ratio of 10:1 (the strain KH8 to the other seven isolates) within the seeded cells, the percentage of nitrogen loss during the aerobic denitrification process was estimated to be 58.4, which was presumed to be converted to $N_2$ gas. When these seeded cells with lactose were applied to plant-scale aeration tank for 56 day to treat high-strength nitrogen in LIW, the removal efficiencies of $COD_{Cr}$ and TN were achieved to be 97.0% and 89.8%, respectively. Under this treatment, the final water quality of the effluent leaving the treatment plant was good enough to meet the water-quality standards. Consequently, the isolated aerobic denitrifiers could be suitable for the additional requirement of nitrogen removal in a limited aeration-tank capacity. To the best of our knowledge, this is the first report of aerobic denitrifiers applied to plant-scale LIW treatment.

용매별 머루 과피 추출물의 항산화 효과 (Antioxidant activity of solvent extracts from Vitis coignetiea skins)

  • 박현실
    • 한국조리학회지
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    • 제17권1호
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    • pp.208-217
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    • 2011
  • 총 페놀 화합물과 플라보노이드 함량은 $53.4{\pm}1.2\;mg$/100 g, $644.7{\pm}3.7\;mg$/100 g으로 ethyl acetate 추출물에서 가장 높은 함량을 보였으며, 전자공여능도 $50\;{\mu}{\ell}$/mL에서 $80.93{\pm}0.58%$로 대조구인 BHT($63.21{\pm}0.72$) 보다 활성이 높았으며, 농도가 증가함에 따라 전자공여능 역시 증가하는 경향을 보였다. 환원력 역시 농도가 $1,000\;{\mu}{\ell}$/mL일 때 ethyl acetate 추출물에서 1.769로 가장 뛰어난 활성을 보였다. $H_2O_2$, $FeCl_2$$CuSO_4$에 대한 항산화 활성도 머루 과피 용매별 추출물의 농도가 높아짐에 따라 유의적으로 활성이 증가하는 경향을 보였으며, ethyl acetate 추출물에서 가장 활성이 높았다. 아질산염 소거능은 pH 1.2의 반응조건에서 R$1,000\;{\mu}{\ell}$/mL의 농도 첨가 시 ethyl acetate 추출물이 $92.5{\pm}2.4%$의 소거능을 나타내었다.

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오미자의 이화학적 특성 및 항산화 활성 (Physicochemical Properties and Antioxidative Activities of Omija(Schizandra chinensis Bailon))

  • 김좌숙;최선영
    • 한국식품영양학회지
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    • 제21권1호
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    • pp.35-42
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    • 2008
  • To develop physiological functionality of Omija extracted with water was evaluated on antioxidative activity. Omija, high acid material with pH 3.6, contain $57.5{\pm}1.03%$ of moisture, and $18.8{\pm}0.12%$ of crude fat. This material have $12.6{\pm}0.04%$ of carbohydrate and $11.1{\pm}0.07%$ of crude protein as well, but ash and crude protein contents were found less than 10%. 10 mineral contents were also found, too; K and Ca showed the highest level, then Al, Mg, Na and Mn were followed. In composition amino acid contents, glutamic acid took the largest portion, $131.7{\pm}1.3$ mg/100 g, aspartic acid $51.5{\pm}0.6%$, and other composition amino acid under 50%. In case of free sugar contents, 7 types were found. Most of them were glucose and fructose. Total phenolic compounds showed the highest level, $2,862.6{\pm}31.7$ mg/100 g. $197.8{\pm}14.6$ mg/100 g of flavonoid and $225.6{\pm}18.2$ mg/100 g were included. In terms of electron donating ability, radical scavenging ability activated as the amount of Omija extract increased. In particular, Omija extract in 1,000 ${\mu}g/m{\ell}$ demonstrated almost similar electron donating ability, $72.4{\pm}0.21%$, to BHT. It was also found that antioxidant activities of electron donating ability, SOD-like ability, hydroxyl radical scavenging ability and nitrite scavenging ability were highly promoted as Omija extract concentration increased. The nitrite scavenging ability was significant when the extract belonged to strong acid region and doping concentrations increased.

포도씨의 총페놀 성분, 항산화능 및 아질산염소거능에 대한 마이크로웨이브 추출조건 예측 (Prediction of the Optimum Conditions for Microwave-Assisted Extraction of the Total Phenolic Content and Antioxidative and Nitrite-scavenging Abilities of Grape Seed)

  • 이은진;김정숙;김현구;권중호
    • 한국식품저장유통학회지
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    • 제18권4호
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    • pp.546-551
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    • 2011
  • 포도씨에 함유된 항산화 및 아질산염소거성분에 대한 마이크로웨이브 최적 추출조건을 예측하고자, 추출조건(microwave power 0~120 W, 에탄올 농도 0~100%, 추출시간 1~5 min)을 독립변수로 하고 조건별 추출물의 총페놀 함량, 항산화능 및 아질산염소거능을 종속변수로 하여 회귀 분석함으로써 최적 추출조건을 예측하였다. 도출된 회귀식의 $R^2$는 0.8024-0.9498 범위로 나타났다. 추출물 기능성분들의 최대 예측값과 최적 추출조건은 총페놀 함량의 경우 3.19%(microwave power 142.32W, 에탄올농도 44.30%, 추출시간 4.23 min)와 항산화능의 경우 1.22(84.44W, 56.60%, 3.28 min)로 나타났다. 그리고 pH 1.2~3.0에서 99.5% 이상의 높은 아질산염 소거능을 보인 추출물의 최적 추출조건 범위는 microwave power 30.80~106.58W, 에탄올 농도 49.32~55.18%, 추출시간 3.72-4.58 min으로 예측되었다. 이상의 결과에서 총페놀 함량과 항산화능은 높은 상관성을 보이면서 microwave power에, 아질산염소거능은 에탄올 농도에 영향을 많이 받는 것으로 나타났다.

농도제어장치를 이용하여 면직물 전처리 공정에서 발생하는 가성소다 폐액의 재활용에 관한 연구 - 재활용 가성소다에 의한 면직물의 정련성 - (A Study on Recycling NaOH from Pre-treatment Process with Concentration Control System - Scouring Ability of Cotton Fabric Treated with Recycled NaOH -)

  • 이언필
    • 한국의류산업학회지
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    • 제6권3호
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    • pp.393-398
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    • 2004
  • This research offers recycling method of NaOH from mercerizing process of cotton fabric. The measuring system of NaOH concentration was designed for the mercerizing process and tested for various conditions which can be occurred in factory. The accuracy of the system was varied as the testing condition was changed. As the concentration of sulfuric acid used for titrating NaOH decreased, the accuracy of measuring system increased. The concentration of NaOH for waste water collected from mercerizing process was measured by 5.2%. As the ratio of newly mixed NaOH increased, moisture regain. water absorbency and whiteness of the specimen increased. The bending rigidity(B) and shear rigidity(G) decreased, as the ratio of newly mixed NaOH increased.

상수원수 수질변화에 따른 전오존 처리효과 및 경제성 평가 (Evaluation of Pre-ozone Treatment and Economic Efficiency as Changing Raw Water Quality)

  • 최동훈;박진식;문추연;이재용;류동춘;장성호;권기원;이수애
    • 한국환경과학회지
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    • 제22권4호
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    • pp.453-461
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    • 2013
  • This study, changes in raw water quality is to indicate on the efficiency of ozone treatment of each pollutant as compared to derive the appropriate operating measures. The appropriate selection for injection rate of pre-ozone and did not inject pre-ozone assess changes in the water. When good water quality, you not injected of pre-ozone to evaluate the economic efficiency of electricity and put the most cost-effective ozone concentration were evaluated. Evaluation remove organic matter and chlorophyll-a concentration level in experiments with each factor of the water DOC> 2.5 mg/L, THMFP> 70 ${\mu}g/L$, Chl-a> 30 $mg/m^3$or less constant process, if you do not need to put pre-ozone showed little impact. It also does not put you in pre-ozone appropriate produce enough power rate savings was calculated as approximately 90 million won. Ability to remove organic materials and the ability to produce disinfection byproducts, and cost-effective decisions by considering the concentration of injection if pre-ozone 1 mg/L was investigated by the appropriate concentration of ozone injection.

반응표면분석에 의한 만가닥 버섯의 추출조건 최적화 (Optimization of Extraction Conditions for Lyophyllum ulmarium by Response Surface Methodology)

  • 김현구;최맑음;김미옥;김공환
    • 한국식품영양과학회지
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    • 제32권4호
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    • pp.574-580
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    • 2003
  • 만가닥 버섯 추출물의 수율 및 전자공여작용, 총폴리페놀 함량, tyrosinase 저해작용, 갈색도, 아질산염 소거작용에 대하여 반응표면분석에 의해 추출조건을 최적화하였다. 만가닥 버섯의 경우 수율은 에탄올 농도에 가장 큰 영향을 받았으며, 전자공여작용의 경우 에탄올 농도가 높고 microwave power가 높은 조건에서 높은 추출률을 나타내었다. 갈변도 및 tyrosinase 저해작용의 경우 에탄을 농도가 증가할수록 microwave power가 증가할수록 더욱 크게 나타났다. 아질산염 소거 작용의 경우 에탄을 농도와 추출시간의 조건에 크게 영향을 받지 않는 것으로 판단되었으며 총 폴리페놀 함량은 에탄을 농도가 증가할수록 증가폭이 크고, microwave power가 증가할수록 추출물의 생리활성이 우수한 것으로 나타났다. 따라서 만가닥버섯의 최적 추출조건 범위는 microwave power 60.15~102.75 watt, ethanol 농도 53.20~64.01%, 추출시간 7.77분으로 예측되었다.

반응표면분석에 의한 산수유 추출물의 추출조건 최적화 (Optimization of Corni fructus Extracts by Response Surface Methodology)

  • 이혜진;도정룡;권중호;김현구
    • 한국식품영양과학회지
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    • 제41권3호
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    • pp.390-395
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    • 2012
  • 산수유의 추출조건별 추출물의 최적 추출조건을 설정하기 위해 중심합성법에 따라 마이크로웨이브에너지(30, 60, 90, 120 및 150 watt), 에탄올 농도(0, 25, 50, 75 및 100%), 추출시간별(1, 3, 5, 7 및 9분)로 추출조건에 따라 생리활성을 측정하였다. 이때 반응표면의 회귀식 $R^2$값이 전자공여작용, tyrosinase 저해효과, SOD 유사활성, 총 폴리페놀 함량에서 각각 0.8937, 0.9254, 0.9552와 0.9708로 분석되었다. 4차원 반응표면분석에 의해 superimposing 하여 최적 추출조건을 얻은 범위는 산수유의 경우 마이크로웨이브 에너지 78~98 watt, 에탄올 농도 3~33%, 추출시간 3.6~9분으로 예측되었다.