• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2004년도 학술대회지
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• pp.130-136
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• 2004

Presence of water in the lubricating oils could be one of the first indicators of potentially expensive and possibly catastrophic failure of the machine as it may cause displace the oil films to prevent the lubrication function of the oil or chemically react with many oil additives resulting in the oil degradation. In order to detect water content quantitatively in lubricating oils many methods and sensors has been developed. Among these, capacitive sensors including sensitive layer, whose dielectric factor changes according to the water content absorbed in the layer, are proposed mainly in the market. But these sensors are not sensitive to a high water content. Besides, the absorbing layer soils in time. In this work, an evaporation of water moisture from oil into air volume above lubricant surface and condensation of water vapor at a cooling surface was used to measure water content quantitatively in an lubricating oil. Laboratory test results of a prototype sensor were presented. Test results showed that the proposed method could be avaliable to measure a low levels of oil moisture.

• 미생물학회지
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• 제39권2호
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• pp.102-107
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• 2003

유류오염 토양으로부터 디젤에 대한 분해능이 있는 균주를 순수분리하였고, 이들 분리 균주의 액체 배양을통하여 균체 생육과 유화활성이 우수한 균주를 최종적으로 선별하였다. 생리,생화학적 특성 및 165 rDNA 염기서열 분석을 실시한 결과, Pseudomonas sp.로 분류 되었으며, Pseudomonas sp. GENECO 1으로 명명하였다. Bioscreen C를 이용하여 디젤 분해를 위한 배양 조건을 조사한 결과 최적 배양온도는 $30^{\circ}C$, 초기 pH는 7.0로 나타났다. Gas chromatography를 이용한 배양 시간별 잔류 디젤 성분분석 결과 96시간 이내에 1.0%의 디젤을 95%이상 분해하였다.

• 한국수소및신에너지학회논문집
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• 제16권2호
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• pp.159-169
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• 2005

Cellulose, consisted of 45 wt% in wood, is usable as fuels and heavy oil additives if depolymerized to monomer unit, because the chemical structures are similar to high octane materials found in gasoline. In this study, thermochemical degradation by solvolysis reaction of cellulose such as the effect of reaction temperature, reaction time and type of solvent on conversion yield and degradation products were investigated. It was found that the effectiveness of the solvent on the sovolysis reaction was as follows; acetone>n-butanol>tetralin. When acetone was used as a solvent, the highest cellulose conversion was observed to be 91.8% at 500$^{\circ}C$, 40min. Combustion heating value of liquid products from thermochemical conversion processes was in the range of 7,330${\sim}$7,410cal/g. The energy yield and mass yield in acetone-solvolysis of cellulose was as high as 66.8% and 37.0 g oil/100g raw material after 40min of reaction at 400$^{\circ}C$. Various aliphatic and aromatic compounds were detected in the cellulose solvolysis products. The major components of the solvolysis products, that could be used as fuel, were mesityl oxide, mesitylene, isophorone.

• Asian-Australasian Journal of Animal Sciences
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• 제9권6호
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• pp.637-642
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• 1996

This experiment was conducted to determine RDP values of locally available feedstuffs that are commonly used in ruminant rations in Bangladesh. Four cattle were fistulated in the rumen for the in situ nylon bag studies. Seventeen different feedstuff sample (9 roughages and 8 concentrates) were evaluated in $4{\times}14cm$ nylon bags and incubated in the rumen for different periods of time (2, 6, 12, 24, 48 and 72 h). The variation in crude protein (CP) contents reflected on the average CP disappearance value throughout the rumen incubation. Soluble fraction (a), insoluble but degradable fraction (b) along with the rate of degradation also varied widely among the various feedstuffs. Under 2% of rumen outflow rate, the percentages of the calculated protein degradabilities of roughages were rice straw, 16.7; maize grass, 70.6; oat grass, 70.8; dhal grass, 71.1; sunhemp, 78.4; napier grass, 62.4; matikalai grass, 72.1; khesarikalai grass, 76.9 and daincha browse, 78.4, respectively. The results in the protein degradabilities (%) in 8% ruminal outflow rate of concentrates were wheat bran, 61.6; rice polish (red), 61.3; rice polish (auto), 30.9; mustard oil cake, 71.8; sesame oil cake, 74.2; coconut oil cake, 57.9; soybean meal, 49.2 and fish meal, 37.9, respectively.

• 한국식품과학회지
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• 제47권5호
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• pp.561-566
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• 2015

350 ppm 농도로 물/카놀라 기름 에멀션에 첨가된 달걀 노른자 위 레시틴은 에멀션 기름의 철 이온에 의한 자동산화와 클로로필에 의한 감광산화에 유의한 영향을 나타내지 않았다. 에멀션의 산화 중 달걀 노른자위 레시틴으로부터 유래한 인지방질은 분해되었으며 감광산화에 비해 자동산화에서 분해 속도가 높았다. 그러나 PC와 PE 사이의 분해 속도는 두 종류의 산화에서 모두 유의한 차이를 보이지 않았다(p>0.05).

• Asian-Australasian Journal of Animal Sciences
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• 제13권3호
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• pp.317-322
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• 2000

In situ and in vivo digestion trials were conducted to determine the degradation of dry matter (DM), crude protein (CP) and effective protein degtadability (EPD), and digestibility of nutrients of Hazelnut kernel oil meal (HKOM), and effects of HKOM on nitrogen (N) balance. In the in situ study, nylon bag were suspended in the rumen of 3 Karayaka rams to estimate protected protein. Protein sources were analyzed for pepsin soluble protein (PSP) using a Pepsin Digestion Method. In the digestion trials, 4 Karayaka rams (36 mo.) were used in a $4{\times}4$ Latin square to evaluate the digestibility of nutrients and N retention to measure effects of diets containing HKOM, soybean meal (SBM) corn gluten meal (CGM) and urea (U). The degradability of DM and CP, and PSP content of HKOM were lower (p>0.05) than that of SBM, but higher (p<0.001) than that of CGM. EPD of HKOM was higher (p<0.01) than that of SBM or CGM. The apparent digestion coefficients of organic matter and CP for HKOM were lower than for SBM, but higher than for CGM. N retention of HKOM was higher than that of SBM and lower than that of CGM (p>0.05). In conclusion, these data may indicate that the HKOM is a high digestible feed source with a value between SBM and CGM.

• Korean Chemical Engineering Research
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• 제43권1호
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• pp.125-128
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• 2005

폴리스티렌의 열분해반응에서 분해반응속도 및 생성되는 오일 중에 함유된 스틸렌모노머와 부산물로 얻어지는 에틸벤젠, 알파메틸스티렌, 다이머, 트라이머 등은 반응온도 및 반응시간 등의 여러 가지 변수들에 의해 영향을 받았으며, 특히 반응시간에 따라 반응성 및 스티렌의 수율은 많은 차이를 보였다. 이 결과는 열분해 반응과정에서 생성되는 유기성 잔류물과 고화탄소의 영향 때문에 기인하였다. 연속열분해시간의 진행과 함께 생성되는 오일의 수율이 저하되었으며 오일에 함유되어 있는 스티렌의 선택도는 감소하였으며 부산물인 알파메틸스티렌, 에틸벤젠, 벤젠, 톨루엔 등의 부산물의 생성은 증가하였다. 본 연구결과로부터 새로운 연속반응을 위한 열분해반응기를 사용하였다.

• 조명전기설비학회논문지
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• 제12권2호
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• pp.15-20
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• 1998

본 연구에서는 주상변압기용 절연유를 대상으로 가속 열화 실험을 수행하면서 절연유의 전기적 특성값인 유전정접과 절연유내의 금속의 양과 절연지의 분해로 생성되는 푸루푸랄양을 조사 연구하였다. 유전정접은 절연유에 변압기 구성재료가 모두 포함된 경우에 많은 영향을 받는 것으로 나타났다. 절연유의 산화에 촉매 작용을 하는 금속의 양을 측정한 결과, 구리의 양은 열화 시간이 지남에 따라서 증가하는 것을 볼 수 있었다. 유전정접과 구리측정값을 비교하여 볼 때 구리측정값이 0.2[ppm] 이상 되면 요주의 범위에 속하는 것으로 볼 수 있다. 푸루푸랄의 양을 측정한 결과 열화시간이 지남에 따라서 푸루푸랄의 양이 증가하는 경향을 보여주었다. 본 연구 결과로 볼 때 주상변압기 예방진단기초자료로 충분히 활용할 수 있었다.

• 한국초지조사료학회지
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• 제34권3호
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• pp.193-201
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• 2014

This study was conducted to examine the effects of defaunation (removal of live protozoa) on fermentation characteristics, degradation of ryegrass hay and $CH_4$ (methane) production by rumen microbes when incubated with plant oils (SO, sunflower oil and LO, linseed oil) in vitro. Sodium lauryl sulfate (0.000375 g/ml) as a defaunation reagent was added into the culture solution and incubated anaerobically up to 24 h at $39^{\circ}C$. pH from defaunation was increased for all treatments from 6 h incubation times (p<0.01-0.001) compared with those from fauantion. Concentration of ammonia-N from defaunation is higher than that from faunation at 3 h (p<0.001), 12 h (p<0.05) and 24 h (p<0.001) incubation times. Defaunation decreased (p<0.01-0.001) total volatile fatty acid concentration at all incubation times. Molar proportions of $C_2$ (acetate, p<0.05-0.001) and butyrate (p<0.01-0.001) were also decreased by defaunation at all incubation times. Molar proportion of $C_3$ (propionate), however, was increased by defaunation at all incubation times (p<0.001). Thus the rate of $C_2$ to $C_3$ was decreased by defaunation at all incubation times (p<0.001). Defaunation decreased ED (effective degradability) of dry matter (p<0.001) and ED of neutral detergent fiber (p<0.001) of ryegrass hay. Defaunation decreased total gas, $CH_4$ production, $CH_4$ % in total gas and $CH_4/CO_2$ at all incubation times (p<0.001). Oil supplementation decreased total gas (p<0.05-0.001), $CH_4$ production (p<0.001) and $CH_4$ % in total gas (p<0.001) compared with control at all incubation times. The result of this study showed that defaunation combined with oil supplementation may cause an alteration of microbial communities and further medicate the fermentation pattern, resulting in both reduction of degradation of ryegrass hay and $CH_4$ production. No difference, however, was observed in all the examinations between SO and LO.

• Journal of Microbiology and Biotechnology
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• 제10권3호
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• pp.333-337
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• 2000

An oil-degrading yeast, Yarrowia lipolytica 180, exhibits interesting cell surface characteristics under the growth on hydrocarbons. An electron microscopic study revealed that the cells grown on crude oil showed protrusions on the cell surface, and thicker periplasmic space and cell wall than the cell surface, and thicker periplasmic space and cell wall than the cells grown on glucose. Y. lipolytica cells lost its cell hydrophobicity after pronase(0.1 mg/ml) treatment. The strain produced two types of emulsifying materials during the growth on hydrocarbons; one was water-soluble extracellular materials and the other was cell wall-associated materials. Both emulsifying materials at lower concentration (0.12%) enhanced the oil-degrading activity of Moraxella sp. K12-7, which had medium emulsifying activity and negative cell hydrophobicity; however, it inhibited the oil-degrading activity of Pseudomunas sp. K12-5, which had medium emulsifying activity and cell hydrophobicity. These results suggest that the oil-degrading activity of Y. lipolytica 180 is closely associated with cell surface structure, and that a finely controlled application of Y.lipolytica 180 in combination with other oil-degrading microorganisms showed a possible enhancing efficiency of oil degradation.