• 대한화학회지
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• 제44권6호
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• pp.501-506
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• 2000

탄화수소의 생성엔탈피를 예측하는 이전의 선형방정식들을 일반화하였다. QSPR 분석에서 사용된 분자를 표현하는 기본적인 인자는 원자와 화학결합이다. 이러한 선택은 이 방법을 매우 간단하게 하며 비용을 줄일 수 있게 한다. 19개의 알켄에 대한 예측치는 실험오차 정도의 편차를 준다. 이 방법의 몇몇 가능한 확장에 대해 지적하였다.

• 한국안전학회지
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• 제14권1호
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• pp.93-100
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• 1999

By using literature data, the empirical equations have been derived which describe the interrelationships of explosion and other related properties of n-alcohols. The properties which have been correlated data are : lower and upper explosive limits, heats of combustion, carbon numbers. Also, the new equation for predicting the temperature dependence of lower explosive limits(LEL) of n-alcohols on the basis of explosive limits, heats of combustion, flame propagation theory and mathematical method is proposed. The values calculated by the proposed equations were a good agreement with literature data within a few percent. From a given explosive properties. by using the proposed equations, it is possible to predict the other properties. It is hoped eventually that this method will permit the estimation of the explosive properties of alcohol with improved accuracy and the broader application for other compounds.

• 한국안전학회지
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• 제11권4호
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• pp.97-106
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• 1996

Some of accidents are based on unstable chemical substances. These chemicals are easily decomposed or Ignited by heats or mechanical shocks like sodium azide. Sodium azide is commonly used as propellant for inflating automotive safety bags and the other chemical manufacturing purposes. The investigation of thermal hazard potential of sodium azide is very important because unexpected traffic accident can be occureed. The experiments were carried out by DSC, TG an ARC in air, oxygen, argon and nitrogen atmosphere. The decomposition temperatures were about $410^{\circ}C$~$420^{\circ}C$ by DSC and $330^{\circ}C$~$370^{\circ}C$ by ARC, this is very significant result for treatment of chemical. The heats of decomposition were about 81 kcal/mol in ai. and 10 kcal/mol in other atmosphere.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 2002년도 춘계학술대회 논문집
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• pp.67-72
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• 2002

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 2001년도 추계학술대회 논문집
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• pp.16-21
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• 2001

• Ocean and Polar Research
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• 제27권3호
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• pp.237-250
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• 2005

To investigate the air mass modification related with Yeongdong Heavy snowfall events, we examined sensible and latent heat fluxes on the East Sea, the energy exchange between atmosphere and ocean in this study. Sensible and latent heats were calculated by a bulk aerodynamic method, in which NCEP/NCAR reanalysis data and NOAA/AVHRR weekly SST data with high resolution were used. Among winter precipitation events in the Yeongdong region, 19 heavy precipitation events $(1995{\sim}2001)$ were selected and classified into three types (mountain, cold-coastal, and warm types). Mountain-type precipitation shows highly positive anomalies of sensible and latent heats over the southwestern part of the East Set When separating them into the two components due to variability of wind and temperature/ specific Humidity, it is shown that the wind components are dominant. Cold-coastal-type precipitation also shows strong positive anomalies of sensible and latent heats over the northern part and over the central-northern part of the East Sea, respectively. It is shown that the sensible heat anomalies are caused mostly by the decrease of surface air temperature. So it can be explained that cold-coastal-type precipitation is closely related with the air mass modification due to cold air advection over warm ocean surface. But in warm-type precipitation, negative anomalies are found in the sensible and latent heat distributions. From this result, it may be postulated that warm-type precipitation is affected by the internal process of the atmosphere rather than the atmosphere-ocean interaction.

• Korean Chemical Engineering Research
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• 제50권1호
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• pp.135-140
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• 2012

반응열량계를 사용하여 1, 2, 3차 아민 수용액과 이산화탄소의 반응열을 각각 측정하였다. 이를 통해 MEA(monoethanolamine, 1차 아민), EAE(2-(ethylamino) ethanol, 2차 아민), MDEA (N-methyldiethanolamine, 3차 아민) 30 wt% 수용액이 $40^{\circ}C$에서 이산화탄소와 반응시 발생하는 반응열을 측정하고 이를 $CO_2$의 loading ratio에 따라 어떻게 변화하는지 평가하였다. 또한, 입체장애 구조를 가지는 AMP(2-amino-2-methyl-1-propanol, 1차 아민), DEA(diethanolamine, 2차 아민), TEA(triethanolamine, 3차 아민) 30 wt% 수용액의 반응열을 각각 측정하여 입체장애 구조가 반응열에 미치는 영향을 살펴보았다. 그 결과, 흡수제의 입체장애 유무와 관계없이 1차 > 2차 > 3차 아민 순으로 반응열이 증가함을 확인하였다. 그리고 입체장애 아민이 동일 차수의 비 입체장애 아민보다 상대적으로 반응열이 낮지만 그 차이는 크지 않음을 확인하였다.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2005년도 제24회 춘계학술대회논문집
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• pp.381-385
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• 2005

최근 우주 개발 기술은 "더 빠르고, 저렴하고, 효율적인"으로 표현할 수 있다. 이런 장치들 사이에서 마이크로 추진 장치는 필수적인 요소이다. 또한 마이크로 노즐은 마이크로 추진 장치에서 가장 중요한 부분이다. 냉가스 추력기의 경우, 마이크로 노즐은 팽창비의 변화를 통해 압축 가스내의 저장된 에너지를 운동에너지로 변환시킨다. 본 논문에서는 노즐 팽창비와 비열비에 따른 마이크로 노즐의 특성을 실험하였다. 추력은 추력 측정 장치에 부착한 스트레인게이지를 사용하여 측정하였다. 또한 실험을 통해 마이크로 노즐의 성능을 평가해보았다.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2003년도 추계학술대회 논문집
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• pp.127-132
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• 2003

In a today industry, the welding is doing a many portion in structure manufacture. This study is simulated heat of heat-effected zone and researched a mechanical properties and ultrasonic characteristic in used the SS400 and the STS304. As the result mechanical properties of steel that become drawing decreased because of remaining stress by strain gardening according as simulated heat temperature rises, but according as temperature rises in material that do simulated heat after have done annealing, mechanical propensity was improved. The velocity and attenuation become different by effect of remaining stress than effect of material internal microstructure in ultrasonic wave test. In the case of STS304, there was change in mechanical properties by effect that is by strain hardening, but there was no change in material that simulated heat after annealing. When become drawing in ultrasonic waves test, according as simulated heat temperatures rise, change of attenuation coefficient is looked, but material that simulated heat after annealing was no change almost both the volocity and attenuation.

• 한국안전학회지
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• 제17권2호
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• pp.39-44
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• 2002

This study was investigated the thermal decomposition characteristics of azo type sponge blowing agent azodicarbonamide(ADCA) using differential scanning calorimeter(DSC). The experimental results showed that the exothermic onset $temperatures(T_{o})$ for ADCA were about $201{\sim}206^{\circ}C$ and evolution heats(Q) were about $144{\sim}150cal/g$. The exothermic onset $temperatures(T_{o})$, exothermic maximum $temperature(T_{m})$ and exothermic final $temperature(T_{f})$ were decreased by decreasing particle size of ADCA and evolution heats(Q) were increased with it. $T_{o}$ and Q for $6.1{\sim}7.2{\mu}m$ ADCA were increased by increasing heating rate at constant sample weight and activation energy was about 37.29kcal/mol. A positive gas pressure was employed in the elucidation of the decomposition behavior of ADCA because it sublimes during linear heating at atmospheric pressure. $T_{o}$ and Q of ADCA tended to increase with a pressure in air or nitrogen. In the case of azo dye, experimental results showed that $T_{o}$ were about $280{\sim}420^{\circ}C$ and Q were about $2{\sim}30cal/g$.