• KSBB Journal
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• 제11권4호
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• pp.476-480
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• 1996

Using Pseudomonas sp. B3, identified and isolated from nature, wastewater containing phenol was treated in a continuous stirred tank reactor and its reaction characteristics were studied. Average concentrations of phenol and COD in effluents were 1.5mg/L and 124mg/L at 0.059h-1 dilution rate, respectively. At the dilution rate higher than 0.063h-1, phenol and COD increased abruptly to 19mg/L and 318mg/L. At the dilution rate higher than 0.059h-1, biomass concentration suddenly decreased and was "washed out". Biomass concentration was 150mg/L at a dilution rate of 0.067h-1. Maximum biomass production rate was 15.98mg/L$.$h at a dilution rate of 0.067h-1. When dilution rate increased above 0.059h-1, effluent phenol concentration abruptly increased and biomass production rate decreased. Maximum cell growth rate(${\mu}$max) and Michaelis-Mentens kinetic constant(Ks) were 0.074h-1 and 0.424mg/L, respectively. From the above result low phenol concentration can be expected at a maximum dilution rate, but reactor becomes unstable due to phenol inhibition.

• Tribology and Lubricants
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• 제26권4호
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• pp.240-245
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• 2010

This paper describes the influence on engine main bearing behavior of the oil film when the fuel is diluted on a diesel engine equipped with DPF system. Oil film pressure and the thickness is calculated in accordance to the fuel dilution. The calculation is based on the numerical analysis of the engine main bearing. As a result, the engine oil viscosity decreased as the fuel dilution increased. This led the increment of the maximum oil thickness pressure. Verification of the minimum oil film thickness settlement by the engine gas pressure and the fuel dilution was confirmed. Destruction possibility of the engine main bearing was foreseen when the engine speed was 2000 rpm with the fuel dilution 15% and the 5W40 engine oil.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2007년도 제34회 KOSCO SYMPOSIUM 논문집
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• pp.13-18
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• 2007

When triple flames propagated in a diverging channel, the effects of fuel dilution on the lift-off characteristics of triple flames were investigated. A multi-slot burner was used to stabilize the lift-off flame especially at weak fuel concentration gradients. It was reported that there is a maximum propagation velocity at a critical concentration gradient in an open jet regardless of fuel dilution. The enhancement of a diffusion flame affected to increase the propagation velocity around critical concentration gradients. However, the influence of a confined channel on the structure of triple flames according to fuel dilution needs to be investigated compared with an open jet case. This study aimed to examine the effect of a confined channel on the structure and the propagation velocity of the triple flames according to fuel dilution. Lift-off height and propagation velocity of triple flames were investigated by employing three kinds of fuel compositions diluted by nitrogen (0%, 25%, 50% $N_2$), Fuel dilution reduced the propagation velocity of triple flame in a confined channel mainly due to the decrease of flame temperature in premixed branch. Despite the difference in fuel dilution, the propagation velocity has a maximum value at a specific fuel concentration gradient even though the critical concentration gradient increases with fuel dilution. And the critical concentration gradient in a confined channel is larger than that in an open jet due to enhancement of convective diffusion.

• 한국식품과학회지
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• 제27권1호
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• pp.129-133
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• 1995

배양환경이 효모 RNA 축적과 autolysis 효율에 미치는 영향을 알아보기 위하여 연속배양을 실시하였다. Dilution rate의 증가에 따라 균체내의 RNA 함량은 증가하여 dilution rate=0.35 $h^{-1}$에서 14.8%를 나타내었고, 더불어 RNA productivity와 specific RNA productivity도 증가하였다. 고정된 D=0.2 $h^{-1}$에서 최적 균체량은 배양온도 $30^{\circ}C$ 에서 얻어졌으나, RNA 함량은 배양온도가 낮아질수록 높은 값을 보여 $24^{\circ}C$에서 12.7%로 나타났다. 한편, autolysis 효율 측면에서 균체 생육속도가 증가할수록 효모 extract의 추출율은 감소하였고, 효모 extract의 분해율은 증가하는 경향을 보였으나, 배양온도는 효모 autolysis 효율에 큰 영향을 미치지 않았다.

• 한국환경보건학회지
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• 제22권3호
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• pp.98-102
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• 1996

This study investigated performance of the phenol degradation and reaction characteristics according to variation of phenol volumetric loading rates and dilution rates in suspension and PACT reactors using Pseudomonas sp. B3. 1. Removal efficiencies of the PAC unit indicated about 100 % with phenol volumetric loading rates from 0.4 phenol $kg/ma^3\cdot d$ to 1.2 phenol $kg/m^3\cdot d$, however, which of the suspension reactor showed about 100% with from 0.2 phenol $kg/m^3\cdot d$ to 0.75 phenol $kg/ma^3\cdot day$. 2. The cell density slightly was decreased from 298.2 mg/l to 272 mg/l, when dilution rate for suspension was reactor increased from 0.4 to 1.41 1/d, and also the cell density suddenly was decreased to 145.5 mg/l and was washed out at the dilution rate higher than 1.60 1/d. But the cell density for the PAC unit was linearly decreased with dilution rate of from 0.8 to 3.0 1/d, and showed 220.75 mg/l at maximum dilution rate. 3. The phenol utilization rate was increased from 0.008 to 0.031 phenol g/l$\cdot$h, when dilution rate for suspension reactor was increased from 0.4 to 1.5 1/d, however, the rate for the PAC unit was linearly increased from 0.017 to 0.061 phenol g/l$\cdot$h as variation changes from 0.017 to 0.061 phenol g/l$\cdot$h dilution rate.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2012년도 제44회 KOSCO SYMPOSIUM 초록집
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• pp.263-266
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• 2012

The characteristics of mild combustion and pollutant emission were investigated computationally with supplied air stream temperature and dilution rate in jet flame. The air was diluted with main combustion products. As dilution rate increased at fixed air temperature, the temperature distribution of burner inside was uniformed and the maximum mole fraction of CO and NO was decreased. In addition, emission indices for NO, CO, and $CO_2$ were compared with air temperature and dilution rate.

• 대한기계학회논문집B
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• 제37권11호
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• pp.1023-1029
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• 2013

IGCC 가스터빈과 공기분리기와의 결합이 중요한데 공기분리기로 공급되는 공기를 가스터빈에서 추출하는 정도와 공기분리기에 남는 질소를 연소기로 공급하는 정도가 중요한 운전 파라미터이다. 이러한 파라미터들이 가스터빈의 성능과 운전성에 미치는 영향은 설계조건인 ISO 조건뿐만 아니라 다양한 외기조건에 대해서도 고려되어야 한다. 본 연구에서는 여러 외기조건에서 터빈 블레이드 온도와 생산 가능한 출력의 한계를 만족하도록 하는 질소희석량과 터빈입구온도를 예측하였다. 공기 결합도는 0 으로 두었다. 해석결과 질소공급량이 많을수록 출력은 높아지고 블레이드 온도는 낮아졌다. 상온 근처의 특정 온도 이하의 외기 조건에서는 가스터빈이 낼 수 있는 최대 출력을 얻을 수 있으나 그 이상에서는 최대 출력을 생산하지 못함을 확인하였다.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2001년도 제23회 KOSCO SYMPOSIUM 논문집
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• pp.51-56
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• 2001

An experiment using preheated air in the coaxial diffusion flame burner was carried out in order to decrease NOx emission and improve the thermal efficiency. Preheated air combustion generally produces high NOx emissions but it was known very well to reduce NOx emission by diluting the combustion air with inert gas in preheated air combustion. In our study, $N_2$ gas was used for diluent and propane was utilized for fuel. We set the combustion air temperature on 300K, 500K, 700K, 900K and dilution level from 21% to 10% in terms of oxygen concentration. NOx emission increased along increment of combustion air temperature and decreased along increment of dilution level(lowering of oxygen concentration in combustion air). Flame-off limit with dilution level enhanced, flame length became longer and the location of maximum flame temperature became lower with increasing of combustion air temperature.

• 미생물학회지
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• 제21권3호
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• pp.163-169
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• 1983

Effects of temperature on the gorwth characteristics and the chemical composition of pseudomonas cells grown under glucose-or methanol-utilizing continuous culture were studied. In a glucose-utilizing continuous culture, optimum dilution rate, agitation, pH, and temperature, for the higher biomass yield were $0.45hr^-$, 7000rpm, pH 7.5, and $30^{\circ}C$, respectively. But in a methanol-utilizing continuous culture, they were $0.125hr^-$, 600rpm, pH 8, and $30^{\circ}C$, respectively. In methanol-utilizing continuous culture, the maximum production rate of the cells was 1.48g, dry wt./1/hr at a dilution rate of $0.45hr^-$, and the cell yield was 0.46g. dry wt./g. glucose. In the methanol-utilizaing continuous culture, the maximum production rate of the cells was 0.33 7g. dry wt./1/hr. at a dilution rate of $0.125hr^-$ and the cell yield was 0.44g dry cell/g. methanol. The contents of protein of the cells increase with the increase ingrowing temperature (from 15 to $30^{\circ}C$), more or less, while the contents of RNA nad carbohydrate of the cells decreased. However, DNA contents of cells growth under the various temperature ranges didn't change. As the temeprature of cultivation rises at a constant dilution rate, the efficiency of RNA in protein synthesis was increased, showing the decreases in the ratio of RNA to protein.

• 한국약용작물학회지
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• 제24권6호
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• pp.458-463
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• 2016

Background: The objective of the present study was to investigate the effect of storage conditions on the growth of Saururus chinensis (Lour.) Baill. rootstock. Methods and Results: Rootstocks of S. chinensis were stored in either soil or vermiculite that had been treated with a control treatment, diluted wood vinegar (50 or 100-fold), DF-100 (50-fold), or 1-naphthylacetamide and at $5^{\circ}C$ or $15^{\circ}C$. After 8 weeks, the stored roots were planted in the field, and both plant height and leaf number were observed after transplantation. The greatest number of leaves ($5.60{\pm}0.80$) was produced by roots that had been stored in soil treated with 100 fold dilution of wood vinegar and at $5^{\circ}C$. Meanwhile the maximum plant height ($6.92{\pm}0.78cm$) at 30 d after transplanting was observed for rootstocks that had been stored in soil treated with the 100 fold dilution of wood vinegar and at $15^{\circ}C$, whereas the maximum plant height at 60 d after transplanting ($26.46{\pm}0.71cm$) was observed for rootstocks that had been stored in soil treated with the 100-fold dilution of wood vinegar and at $5^{\circ}C$. Therefore, the storage of rootstocks in soil treated with the 100-fold dilution of wood vinegar and at temperatures at or below $5^{\circ}C$ was most effective, and it can be used to prevent the decay of roots during the postharvest management of S. chinensis rootstocks. Conclusions: The results of the present study indicate that, among the parameters examined, the storage of roots in soil that had been treated with the 100-foil dilution of wood vinegar is the most effective method for improving the growth of S. chinensis.