• Defense and Technology
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• no.2 s.276
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• pp.58-65
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• 2002

이 글은 최근에 개발되어 큰 관심을 모으고 있는 흡착성능이 대단히 우수하고 가벼운 활성탄소섬유(ACF 혹은 섬유상 활성탄소)에 유기인 화합물 신경작용제의 모델가스인 DMMP를 통과시켜 흡착 파과곡선을 측정하고 방독면과 보호와의 핵심소재인 첨착활성탄소(ASC-AC)와 제거능력을 비교하면서, ACF가 현재 사용되고 있는 독성가스 제거용 첨착활성탄소를 대체할 수 있는 가능성을 보고자 하였다.

• Korean Journal of Environmental Agriculture
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• v.7 no.2
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• pp.136-145
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• 1988

To investigate the seasonal changes of various organic and inorganic compounds in compost, carbon compounds in compost were analyzed at various composting periods. Contents of organic matter, cellulose, total carbon, organic carbon and biodegradable carbon in compost were decreased with the progress of composting. In contrast, contents of lignin and nonbiodegradable carbon were increased a little with the progress of composting, but effective contents of lignin were decreased with the lapse of composting time, while effective contents of nonbiodegradable carbon were not changed. Total carbon contents in organic matter in compost were decreased within 9 weeks after composting, and then increased thereafter. Difference between average values of total and biodegradable carbon contents was 6.2%. Actual decay rates of all the carbon compounds were higher than decay rates of the compounds at all the experimental periods. Both of actual decay rate and decay rate of all the carbon compounds were increased rapidly within 2 weeks after composting, and thereafter the rates were increased slightly with the lapse of composting time. Especially the decay rates of cellulose were increased from 9 to 21 weeks after composting. Actual degradation capacity showed the same tendency to degradation capacity of all the carbon compounds in compost. Decay rate and degradation capacity of lignin in compost had minus values, while actual decay rate and actual degradation capacity had plus values. Highly positive correlations were observed among organic matter, cellulose, total carbon and biodegradable carbon one another. Nonbiodegradable carbon showed highly negative correlation with organic matter, cellulose, total carbon, organic carbon and biodegradable carbon, respectively. The same tendencies were observed between lignin and organic matter, cellulose, total carbon, organic carbon and biodegradable carbon. Highly positive correlation was observed between lignin and nonbiodegradable carbon in compost.

• Journal of the Korean Electrochemical Society
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• v.24 no.3
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• pp.42-51
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• 2021

Dissociation into Lithium-polysulfide electrolyte due to repeated cycles during the Lithium/Sulfur battery reaction is a major problem of reduced battery lifespan. We searched for a porous carbon with a large specific surface area that infiltrated S to prevent liquid Lithium-polysulfide from being dissolved in electrolyte, induce adsorption of Lithium-polysulfide, and further increase conductivity. In order to obtain porous carbon spheres with a large specific surface area, the carbon spheres of 1939 m²/g were raised to 2200 m²/g through additional KOH treatment. In addition, through heat treatment with S, a carbon sulfur compound containing 75 wt% of S was fabricate and material analysis was conducted on the possibility of using the cathode material. The electrochemical characteristics of the Reference (622; sulfur: 60%, conductive material: 20%, binder: 20%) pouch cell and the pouch cell made using 75wt% of carbon sulfur compound were analyzed. 75wt% of carbon sulfur pouch cell showed a 20% increase in lifespan and 10% improvement in C-rate compared to the Reference pouch cell after 50 cycles.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2001.11a
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• pp.360-361
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• 2001

VOCs 배출원은 크게 인위적인 배출원과 자연적인 배출원으로 나눌 수 있다. 식물은 자연 발생적 VOCs(NVOCs)의 가장 주요한 배출원이며, 대기 중으로 유입되는 반응성이 강한 탄소의 주요한 배출원이다. 이소프린, terpene, 알콜, 카르보닐화합물, 에스테르 등은 식물에서 발생되는 대표적인 탄화수소화합물들이다. 이러한 물질들은 에어로졸의 형성 등 전지구적 대기화학반응, 광역적 광화학산화제 (특히 오존)의 형성, 탄소순환의 수지균형 비도시지역의 산성침적에 기여하는 유기산의 생성 등에 주요한 영향을 끼친다. (중략)

• Applied Chemistry for Engineering
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• v.29 no.4
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• pp.413-418
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• 2018

Cypress woods treated individually with boric acid (BA4), ammonium pentaborate (APB4), or BA4/APB4 additives were examined for combustion gases. Each of the specimens was painted with a 4 wt% solution of boron compounds three times. Dried at room temperature, the combustion gas was analyzed using a cone calorimeter (ISO 5660-1). Consequently, the second maximum oxygen consumption rate of the specimen treated with boron compounds was 0.1067 to 0.1246 g/s, which was 5.3 to 18.9%, respectively lower than that of the blank specimen. The specific extinction area of specimens treated with BA4 and APB4 was also 2.0 to 19.0% lower, respectively. However, treated with BA4/APB4 showed 21.2% higher than that of the blank specimen. The maximum carbon monoxide concentration of the specimens with boron compounds was reduced by 0 to 25%. It was estimated to be 1.6 to 2.2 times higher than the permissible exposure limits by Occupational Safety and Health Administration (OSHA), indicating a fatal toxicity. The boron compounds were effective in reducing carbon monoxide, but didn't meet the OSHA limit. The boron compound inhibited the burning behavior of the cypress wood, which suppressed the second maximum oxygen consumption rate by 5.3 to 18.9% and the maximum carbon monoxide generation by 0 to 25%.

• Fire Science and Engineering
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• v.33 no.4
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• pp.16-27
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• 2019

A burning test was conducted on the smoke and combustion gases generated from cypress wood treated with sodium silicate, 3-aminopropyltrimethoxysilane sol, 3-(2-aminoethylamino)propylmethyldimethoxysilane sol, and 3-(2-aminoethylamino) propyltrimethoxysilane sol. The silicone compound sol was applied to each of the cypress wood specimens three times with a brush. The smoke and combustion generation gas were analyzed using a cone calorimeter (ISO 5660-1) and the smoke was also evaluated by applying new smoke risk assessment method. The smoke performance index (SPI) of the cypress treated with silicone compound increased 1.66 to 8.42 times and the smoke growth index (SGI) was 11.8 to 88.2%, respectively. The smoke intensity (SI) is expected to be 1.0~50.5% lower than that of the base specimens, resulting in lower smoke and fire hazards. The third maximum carbon monoxide (CO_peak) concentration of the specimens treated with silicone compounds was 22.5~33.3% lower than that of the base specimens. On the other hand, it produced potentially fatal toxicity that was 1.48~1.72 times higher than the US Occupational Safety and Health Administration (OSHA) acceptance standard (PEL). Cypress wood itself produced a high carbon monoxide concentration, but the silicon compound played a role in reducing this level.

• Applied Chemistry for Engineering
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• v.29 no.6
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• pp.670-676
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• 2018

Experiments on combustion gases generation of untreated cypress specimens or treated with boric acid, ammonium pentaborate, and boric acid/ammonium pentaborate additive were carried out. Test specimens were painted three times with 15 wt% boron compound aqueous solutions. After drying, the generation of combustion gas was analyzed using a cone calorimeter (ISO 5660-1). As a result, comparing to untreated specimen, the smoke performance index (SPI) of the specimens treated with the boron compound increased by 1.37 to 2.68 times and the smoke growth index (SGI) decreased by 29.4 to 52.9%. The smoke intensity (SI) of the specimens treated with boron compounds is expected to be 1.16 to 3.92 times lower than that of untreated specimens, resulting in lower smoke and fire hazards. Also, the maximum carbon monoxide ($CO_{peak}$) concentration of specimens treated with boron compounds was 12.7 to 30.9% lower than that of untreated specimens. However, it was measured to produce fatal toxicities from 1.52 to 1.92 times higher than that of permissible exposure limits (PEL) by Occupational Safety and Health Administration (OSHA). The boron compounds played a role in reducing carbon monoxide, but it did not meet the expectation of reduction effect because of the high concentration of carbon monoxide in cypress itself.

• 한국신재생에너지학회:학술대회논문집
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• 2007.11a
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• pp.75-78
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• 2007

천연가스의 수증기 및 이산화탄소 복합 개질은 탄화수소화합물과 이산화탄소를 원료로 사용하여 수소를 생산하는 공정으로, 온실가스로 지목되고 있는 주요 화합물을 수소와 일산화탄소 혼합 가스로 전환시켜 합성 반응 또는 연료전지에 사용할 수 있도록 해준다. 본 연구에서는 $MgAl_2O_4$를 지지체로 하는 니켈계 촉매를 제조하여 수증기 및 이산화탄소 복합 개질 반응에 사용하였으며, 기존의 수증기 개질촉매 적용 시 문제가 되었던 탄소 침적에 의한 촉매 비활성화를 피할 수 있었다. 개발된 촉매 레시피를 바탕으로 펠릿 촉매를 제조하여 0.1 bpd규모의 Fischer-Tropsch 합성 반응에 적용 가능한 튜브형 반응기에 적용하여 수증기 및 이산화탄소 복합 개질 반응을 실시하였으며, 반응기의 온도 구배, 가스 조성 변화를 관찰하였다. 반응 조건에 따른 촉매 및 반응기의 성능 최적화를 실시하여 최적 촉매 및 반응기 성능을 모색하고자 하였다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.10
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• pp.69-74
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• 2017

In this study, cholesteryl 4-n-alkoxybenzoates (Chol-n), with alkyl groups used for controlling the temperature of transition to the liquid crystal phase, were synthesized, and the effects of the length of the alkyl groups on the physical properties of the liquid crystal compounds were investigated. The chemical structures and thermal and liquid crystalline properties of the synthesized compounds were investigated by Fourier transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance spectroscopy ($^1H$-NMR), differential scanning calorimetry (DSC), and polarizing optical microscopy (POM). The synthesized compounds showed melting transition temperatures ($T_m$) in the range of $103^{\circ}C$ to $143^{\circ}C$ and all of the compounds except Chol-6 exhibited a wide liquid crystal phase temperature range of about $60^{\circ}C$ to $100^{\circ}C$. No correlation between the number of carbon atoms in the molecule and the thermal properties of the compounds was found. All of the synthesized compounds showed an enantiotropic cholesteric phase, which was accompanied by a chiral smectic phase in the compounds Chol-6, Chol-8, Chol-9, and Chol-10. All of the compounds exhibited thermochromism in the liquid crystal state, and their color changed from red to blue as the temperature was increased.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2000.05a
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• pp.91-93
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• 2000