• Korean Journal of Soil Science and Fertilizer
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• v.15 no.2
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• pp.141-146
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• 1982

Laboratory and greenhouse experments were conducted to find out the optimum dilution time of methane fermented effluent of hog waste which was high pH (7.85), $NH_4$-N (683ppm), electric conductivity (8.3mmhos/cm) and BOD (about 1,000ppm) and the interval of effluent change which will provide maximun yield of green algae (Scenedesmus accuminatus), duck weed (Lemner minor L.) and Azolla anabaena (Azolla pinnata). The results of this experiment are summerized as follows. 1. The maximum yield were obtained at 5 times diluted effluent ($NH_4$-N : 137ppm) and exchange of 4 day intertval, from 25 times to 50 times dilution ($NH_4$-N : 7-14ppm) and 4 day interval, and 50 times dilution ($NH_4$-N : 14 ppm) and exchange the effluent at 4-8 day interval for green algae, duck weed and azolla growth, respectively. 2. Purification of the effluent was enhenced by growth of the green algae, duck weed and azolla due to decrease of pH, $MH_4$-N and electric conductivity of effluent. The degree of purification was higher in case of azolla growth than duck week growth.

• Proceedings of the KIEE Conference
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• 1986.07a
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• pp.459-462
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• 1986

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2000.11a
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• pp.140-145
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• 2000

BTX는 석유화학곧업에서 생산되는 방향족탄화수소 화합물의 주요 생산품목인 Benzene, Toluene, Xylene을 일컫는 말로서 석유화학공정에서 간단히 줄여서 쓰는 용어이다. 벤젠, 톨루엔, 크실렌 등은 페인트 희석제로 쓰이는 유기용매의 주성분들이며, 인체에 중독성을 나타내는 유해물질이기도 하며 소방법상에서는 인화성액체인 4류 위험물로 취급하고 있다.(중략)

• 전기의세계
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• v.37 no.10
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• pp.25-30
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• 1988

전력케이블의 절연특성은 케이블에 인가되는 stress의 종류에 따라 교류.직류.충격전압등에 대한 내전압특성과 유전율.유전정접.누설저항등의 변화로 나타나는 손실 특성으로 대별할 수 있다. 이 가운데 전력케이블의 사용여부를 판정하는 기준은 주로 내전압특성이 되기 때문에 내전압특성의 변화 원인 및 사용조건에 따른 변화경향을 개략한다.

• The Korean Journal of Food And Nutrition
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• v.17 no.1
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• pp.18-24
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• 2004

Nutritional characteristics and antioxidation effects of Yakju brewed with natural plants(fine tree leaves, bamboo leaves, ginger, cinnamon and licorice root) were tested. With regard to the contents of phenolic compound, Yakju brewed with natural plants was about 1.7 times higher than Yakju which were not brewed with natural plants. In Yakju brewed with natural plants, lactose content was the highest but maltose was not detected. Minerals were detected in the order of P>K>Mg>Ca>Fe and the content of Fe and Na had a little changes during its 30 days storage. Amino acid contents were getting lower during storage. They were about 28% lower compared 3 days with 30 days storage. Electron donating ability of Yakju and its diluents were tested by DPPH. It was found that the electron donating ability of Yakju was lower as the dilution ratio got higher and as the storage terms got longer. Also, Yakju brewed with natural plants has 95.7∼96.7% of electron donating ability during 30 days storage without regard to its dilution ratio. Superoxide dismutase(SOD) like activity was in inverse proportion to dilution ratio and storage days. The highest SOD like activity was shown 51.5% and 53.9% in 3 days storage Yakju brewed with natural plants and in its 2 times diluents, respectively.

• Fire Science and Engineering
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• v.32 no.6
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• pp.22-27
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• 2018

The flame length in coaxial diffusion flame configurations was investigated when the kerosene fuel flow rate, temperature of the oxidizer stream, and inert gas concentrations in the oxidizer stream were varied. The diffusion flame was photographed using a Schlieren camera under each of the experimental conditions and the obtained images were then digitized to measure the flame length. The measured flame lengths were proportional to the kerosene fuel flow rate and increased with increasing temperature of the oxidizer stream. In addition, increases in the inert gas concentration in the oxidizer stream resulted in stretching of the flame. In particular, the flame was further elongated in the oxidizer steam diluted with helium gas. Inert substitutions in the oxidizer stream that can adjust the viscous drag are believed to be one of the important mechanisms that affect the length of the coaxial diffusion flames.

• KSBB Journal
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• v.4 no.3
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• pp.253-258
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• 1989

It was investigated that the influent sugar concentration and the dilution rate have an influence on the ethanol fermentation characteristics at steady state in a chemostat culture of K. fragilis using Jerusalem Artichoke juice as substrate. And also the optimum condition of high ethanol productivity and low residual sugar output in the ethanol production by K. fragilis, was clarified to be given at a dilution rate of 0.22/hr and at an influent sugar concentration of 85g/l.

• 한국연소학회:학술대회논문집
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• 2003.12a
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• pp.177-184
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• 2003

Stabilization mechanism of lifted flame in the near field of coflow jets has been investigated experimentally and numerically for methane fuel diluted with nitrogen. Lifted flames were observed only in the near field of coflow jets until blowout occurred in the normal gravity condition. To elucidate the stabilization mechanism for the stationary lifted flames in the near field of coflow jets for the diluted methane having the Schmidt number smaller than unity, the behaviors of the stationary lifted flame in microgravity and unsteady propagation phenomena were investigated numerically at various conditions of jet velocity. It has been founded that the buoyancy plays an important role for flame stabilization of lifted flame in normal gravity and the stabilization mechanism is due to the significant variation of the propagation speed of lifted flame edge compared to the local flow velocity at the edge.

• Journal of the Korea Organic Resources Recycling Association
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• v.10 no.2
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• pp.65-70
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• 2002

The previous studies showed that rumen microorganisms had an enhanced waste-degrading capability and controlling the dilution rate was very effective in improving acidification efficiency. Generally the composition of food waste has a small deviation value, but one of the waste components (grains, vegetables or meats) can be increased dramatically depending on a seasonal variation. Thus, it is important to evaluate the efficiency of acidogenic fermentation in this case. Each component was spiked to be 80% of the total waste in R1 (grains), R2(vegetables), and R3 (meats). In Rl, rapid degradation occurred during the initial two days. R2 showed similar performance to that of general food waste. In R3, degradation retarded in the initial stage and then increased after controlling the dilution rate. The acidification efficiencies of the reactors were 88.7 (R1), 73.5 (R2), and 62.1% (R3), respectively. Therefore, the fermentation efficiency was kept over 62% regardless of waste components, indicating that it was stable to acidify food waste by employing rumen microorganisms and controlling the dilution rate.

• Analytical Science and Technology
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• v.20 no.6
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• pp.488-495
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• 2007

A wallpaper having many surfaces in indoor is composed of various raw materials. In this study, TVOC contribution from raw materials of PVC wallpaper was evaluated by using headspace-solid phase microextraction (HS-SPME)-GC/MS. Samples were diluent, resin stabilizer, plasticizer, filler, blowing agent and PVC resin. 9 mL of each sample was put into 22 mL glass vial and they were equilibrated for 1 hour at $100^{\circ}C$. Headspace in vial was absorbed to $75{\mu}m$ Carboxen-PDMS fiber and analyzed by GC/MS. Aromatic compounds like a toluene, ethylbenzene and xylene, ketones compounds like a acetone, methoxyacetone and 2-butanone and alkane compounds like a nonane decane and undecane were identified from raw materials. And alcohol compounds like a ethanol and butanol and aldehydes were detected. TVOC emission of diluent, resin stabilizer, plasticizer, PVC resin, blowing agent and filler were $54.20{\mu}g/g$, $32.88{\mu}g/g$, $0.50{\mu}g/g$, $0.88{\mu}g/g$, $0.22{\mu}g/g$ and $0.11{\mu}g/g$, respectively. Contribution of TVOC emission of diluent, resin stabilizer and PVC resin that were concerned about add ratio were 0.708, 0.129, 0.115, respectively. In conclusion, it's necessary to reduce TVOC emission through improvement of diluent, resin stabilizer and PVC resin. Also, HS-SPME-GC/MS method which was developed in this study will be used for raw materials analysis effectively.