• 한국안전학회지
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• 제9권2호
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• pp.12-17
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• 1994

Smoke evolved from burning cellulose insulation treated with boric acid-borax-alum as combustion retardants has been studied using a light absorption method. It has been shown that the quantity of smoke are decreased with the increase of oxygen concentration. Applied fire retardants did not increase smoke generation from investigated cellulose insulation in range of themal degradation without flaming. These same fire retardants increased from in the range of flaming combustion. The results of this work have been analysed using imperical equation, which correlated the smoke density at oxygen content of combustion transition. This equation may be. $\sigma$=$\sigma$$_{T}$ exp｛-7.24$\times$10$^{-7}$ ( $O_2$ $O_{2.T}$)｝Where $O_2$is the concentration of oxygen in the oxidizing gas, and $O_{2.T}$ refers to oxygen concentration of combustion transition.n.n.n.

• 한국임상수의학회지
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• 제20권1호
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• pp.110-114
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• 2003

The Korean Chinese Chives(Allium tuberosum Rottler) are a perennial herb and have been used from ancient as food and medical purpose in Korea. They are known to posses diuresis, sthemia activities and used for the treatment or anemia, haematemesis, and eczema. Recently the Korean Chinese Chives have been studied on the morphologic property, the classification of origin and chemical constituent. However there has not been studied on kg) (or 6 days and observed the hematological effects in dogs. The results are as follows, 1. The red blood cell count was significantly (P < 0.05) decreased on day 2. 2. The reduced glutathion(GSH) concentration was significantly (P< 0.05) increased on day 4 and Met-hemoglobin concentration was significantly (P< 0.05) increased on 3 hrs after administration. 3. Packed cell volume(PCV) and hemoglobin concentration were not showed significant difference during experimental periods. 4. The mean corpuscular volume(MCV) was significantly(P < 0.05) increased on 3 hours after administration.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2000년도 학술발표회 발표논문집
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• pp.617-622
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• 2000

Concentration of pollutants and discharge were monitored regularly at paddy field area during irrigation periods. The amounts of irrigation water during irrigation water during irrigation periods in 1999 were 3690mm. The concentration of pollutants in ponded water are high during fertilizer application period. The ratio of discharge of direct runoff Q$\_$D/ to the total runoff is 9%. The ratios of the load of direct runoff L$\_$D/ to the total load L$\_$T/ are 6% for T-N, 16% for T-P and 16% for COD. It was found that the ratios of the concentration are 0.7 for T-N, 1.8 for T-P and 1.9 for COD. The unit load of T-N, T-P and COD during irrigation periods were 12.1kg/㏊, 0.42kg/㏊ and 85.7kg/㏊, respectively

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1998년도 춘계학술대회 논문집
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• pp.87-91
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• 1998

In this paper, We analyzed the current-voltage characteristics with n-type silicon substrates concentration and temperature variations (Room temperature, 50$^{\circ}C$, 75$^{\circ}C$) in platinum silicide and silicon junction. The electrical parameters of measurement are turn-on voltage, saturation current, ideality factor, barrier height, dynamic resistance in forward bias and reverse breakdown voltage according to variations of junction concentration of substrates and measurement temperature variations. As a result, the forward turn-on voltage, reverse breakdown voltage, barrier height and dynamic resistance were decreased but saturation currents and ideality factor were increased by substrates increased concentration variations in platinum silicide and n-silicon junction. In increased measurement temperature (RT, 50$^{\circ}C$, 75$^{\circ}C$), the extracted electrical parameter values of characteristics were rises by increased temperature variations according to the forward and reverse bias.

• Journal of the Optical Society of Korea
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• 제19권2호
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• pp.199-205
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• 2015

We investigated the effects of the thickness and doping concentration in p- and n-type poly-Si layers on the performance of a solar cell based on a carbon fiber in order to improve the energy conversion efficiency of the cell. The short-circuit current density and open-circuit voltage of the carbon fiber-based solar cell were significantly influenced by the thickness and doping concentration in the p- and n-type poly-Si layers. The solar cell efficiency was successfully enhanced to ~10.5%.

• Bulletin of the Korean Chemical Society
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• 제30권4호
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• pp.902-906
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• 2009

It is found that that the coating N-acetyl cysteine (NAC) on gold surfaces may be used to design the distribution of either gold particle adsorbed to the $TiO_2$ surface or vice versa by adjusting the electrostatic interactions. In this study, we investigated electrostatic properties of the NAC-coated-gold surface and the $TiO_2$ surface. The surface forces between the surfaces were measured as a function of the salt concentration and pH value using the AFM. By applying the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory to the surface forces, the surface potential and charge density of the surfaces were quantitatively acquired for each salt concentration and each pH value. The surface potential and charge density dependence on the salt concentration was explained with the law of mass action, and the pH dependence was with the ionizable groups on the surface.

• 대한환경공학회지
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• 제32권3호
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• pp.256-263
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• 2010

본 논문은 염분농도가 호기성 생분해도에 미치는 영향을 파악하고, 그 결과를 수산물 가중 폐수 처리 위한 기초자료로 사용하기 위하여 수행되었다. $Cl^-$농도(1,400~18,000 mg/L)에 따른 유기물 제거효율 검토결과, $Cl^-$ 6,000 mg/L 이하에서 미생물들은 염분에 적응하였으나 $Cl^-$ 12,000 mg/L 이상에서는 반응시간이 길어져도 처리효율이 개선되지 않는 것으로 조사되었다. 생물학적 분해불가능한 용존성 유기물 함유계수 $Y_I$와 미생물 신진대사에 의한 inert 물질 생성계수 Yp는 염분농도가 증가할수록 증가하였으며, $Cl^-$ 농도(0~18,000 mg/L)에 따른 용존성 유기물 비율은 10.8~13.1%로, 미생물 신진대사에 의한 inert 물질 생성비율은 7.0~24.6%로 조사되었다. $NH_3$-N 제거효율은, 원폐수는 HRT 18 hr에서 96.2%의 제거효율을 보였으나, $Cl^-$ 6,000 mg/L, HRT 22 hr에서 96.5%, $Cl^-$ 12,000 mg/L, HRT 30 hr에서 90.2%, $Cl^-$ 18,000 mg/L, HRT 45 hr에서 90.3%의 제거효율을 나타내, 질산화 과정이 유기물 제거 보다 염분농도에 더 민감한 것으로 조사되었으며, 폐수내 $Cl^-$ 6,000 mg/L 이상부터는 $NO_2$-N에서 $NO_3$-N로의 전환율도 낮게 조사되었다.

• 한국대기환경학회지
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• 제34권1호
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• pp.166-176
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• 2018

The n-alkanes which are stable compounds in the atmosphere are emitted by anthropogenic sources and biological sources. The goal of this study is to understand characteristics of n-alkane distributions in $PM_{2.5}$ of the Anmyeon Island which is one of background site in Korea. The concentration of n-alkanes in $PM_{2.5}$ was measured at Anmyeon Island for one year from June 2015 to May 2016. The average concentration of total n-alkanes (${\sum}$ n-alkanes) from C20 to C34 was $14.02{\pm}10.26ng\;m^{-3}$ and ranged from 1.77 to $47.65ng\;m^{-3}$. Various diagnostic parameters were used to identify the source. As a result, it is considered that Anmyeon Island had a large influence of biological sources during non-heating period, while the influence of anthropogenic emission during the heating period was significant. Principle Component Analysis (PCA) was performed and yielded three components that accounted for 93.6% of the total variance in n-alkanes. Factor 1, which accounted for 42.3% of the total variance, indicated anthropogenic source including fossil fuel and biomass combustion, while, Factor 3 was interpreted as the biological sources such as plant wax.

• 한국재료학회지
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• 제5권8호
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• pp.960-965
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• 1995

반응 가스 분압의 조절에 의한 HCD식 이온 도금 법으로 다양한 조성의 Ti(C, N) 경질 피막을 ASP30 공구강에 도금하였고 이 피막의 내마모성에 대한 조성의 영향을 경도, 밀착력 및 마모기구의 변화 등의 관점에서 고찰하였다. 경도는 질소나 탄소와 같은 비금속 성분량의 증가에 비례하지만 탄소함유량의 중가는 밀착력을 오히려 감소시켰다. 이 경향은 피막 밀도가 비교적 작은 정략적비 이하인 구간([C+N]/Ti<1)에서 보다 그 이상인 조성에서 영향이 뚜렷하였다. 따라서 피막의 내마모 특성은 높은 경도를 유지할 수 있는 ([C+N]/Ti>1)인 구역 내에서 밀착력 저하에 의한 adhesive 형태로의 마모 기구 변이를 억제할 수 있는 저 탄소 조성을 가질 때 최대로 된다.

• 대한화학회지
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• 제55권2호
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• pp.163-168
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• 2011

다양한 농도의 N-methyl acetamide 수용액에서 계면 활성제의 농도에 따른 계면활성제들 (sodium caprylate, sodium laurate, sodium palmitate, sodium stearate, sodium oleate, sodium dodecyl sulphate, lithium dodecyl sulphate)의 몰 전도도 변화를 $30{\pm}0.2^{\circ}C$의 일정온도에서 연구하였다. 각각의 계면활성제에 대한 임계 미셀 농도 (CMC)를 측정하였다. 수용액에 N-methyl acetamide이 공존할 때에는 여러 계면 활성제의 CMC 값이 수용액에서의 CMC 값보다 더 낮고, 미셀 형성에 대한 추진력은 소용매성과 관련되었다. N-methyl acetamide 수용액에서 양쪽성 자기-조직화를 추진하는 계면활성제-용매의 상호작용에 대해 논의하였다. 이 결과들을 설명하기 위하여 미셀 시스템에 대한 열역학적 매개변수들을 추정하였다.