• 한국막학회:학술대회논문집
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• 한국막학회 2004년도 Proceedings of the second conference of aseanian membrane society
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• pp.98-101
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• 2004

Utilization of biomass resources has considerable contribution to the reduction of carbon dioxide emission. Ethanol is one of the biomass products and is used as an additive to gasoline in several countries. Conventional process to produce ethanol involves energy-intensive azeotropic distillation. Pervaporation (PV) or vapor permeation (VP) is considered to be an alternative separation process to the conventional process.(omitted)

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.418-419
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• 2006

In the present, the focus is on the synthesis of nanostructured TiC/Co composite powder by the spray thermal conversion process using titanium dioxide powder has an average particle size of 50 nm and cobalt nitrate as raw materials. The titanium-cobalt-oxygen based oxide powder prepared by the combination of the spray drying and desalting methods. The titanium-cobalt-oxygen based oxide powder carbothermally reduced by the solid carbon. The synthesized TiC-15wt.%Co composite powder at 1473K for 2 hours had an average particle size of 150 nm.

• 한국연소학회지
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• 제22권1호
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• pp.23-31
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• 2017

Large-scale fuel tanks emit massive amount of hardly-combustible VOC mixtures which are light hydrocarbon species in dilution with nitrogen and carbon dioxide. We have developed a lab-scale burner to combust those VOC mixtures by use of a turbulent partially-premixed flame as a pilot flame. For a higher HC treatment ratio, the mixture gases were reformed by a rotating arc plasma device. The results showed that the nitrogen mole fraction and the injecting speed of the VOC mixture influence on the performance of the burner. It was also found that the size of the pilot flame and the power supplied to the plasma device determine the overall HC treatment ratio and the concentrations of CO and NOx in the exhaust gas.

• Preventive Nutrition and Food Science
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• 제6권4호
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• pp.240-243
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• 2001

Fresh pasta was packaged in a modified atmosphere of 22% $CO_2$/78% $N_2$ and compared with a control air package for its quality changes during storage at 8$^{\circ}C$. The modified atmosphere packaging suppressed the microbial growth of total aerobic bacteria and yeasts/molds with a concomitant reduction in the rates of physical and chemical quality changes, and thus successfully extended the shelf life of fresh packs from 20 days of air packs to 40 days based on microbial criterion of 10$^{6}$ cfu/g. The shelf life extension was greater when the initial microbial quality of the product was better.

• Journal of Industrial and Engineering Chemistry
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• 제68권
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• pp.301-310
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• 2018

Various catalysts such as formic acid, acetic acid, sodium hydroxide, sodium bicarbonate, carbon dioxide and nitrogen gas were used for hydrolyzates production from deoiled mackerel muscle by subcritical water hydrolysis. Above 99% hydrolysis yield was obtained using sodium bicarbonate catalyst at $260^{\circ}C/70bar$. Histamine and heavy metals concentration were reduced in hydrolyzates. Highest amount of amino acid (400.36 mg/g) and reducing sugar (24.75 mg/g) were found in hydrolyzate obtained at $260^{\circ}C/70bar$ and $220^{\circ}C/30bar$, respectively with sodium bicarbonate catalyst. Antioxidant and ACE-inhibitory activities were significantly higher in hydrolyzates obtained using sodium bicarbonate than that of others.

• Advances in concrete construction
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• 제7권3호
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• pp.167-174
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• 2019

Metakaolin (MK), which is increasingly being used to produce high performance concrete, is produced by calcining purified kaolinite between 650 and $700^{\circ}C$ in a rotary kiln. The carbonation resistance of metakaolin blended concrete is lower than that of control concrete. Hence, it is critical to consider carbonation durability for rationally using metakaolin in the concrete industry. This study presents microstructure modeling during the carbonation of metakaolin blended concrete. First, based on a blended hydration mo del, the amount of carbonatable substances and porosity are determined. Second, based on the chemical reactions between carbon dioxide and carbonatable substances, the reduction of concrete porosity due to carbonation is calculated. Furthermore, $CO_2$ diffusivity is evaluated considering the concrete composition and exposed environment. The carbonation depth of concrete is analyzed using a diffusion-based model. The proposed microstructure model takes into account the influences of concrete composition, concrete curing, and exposure condition on carbonation. The proposed model is useful as a predetermination tool for the evaluation of the carbonation service life of metakaolin blended concrete.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2019년도 추계 학술논문 발표대회
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• pp.178-179
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• 2019

The cement industry is a large amount of carbon dioxide emission industry, and research and development on non-cement composition is underway at the time when the absolute reduction of cement use is urgently needed. In addition, limestone fine powder is a by-product and is required to be recycled in terms of resource circulation. The compressive strength of the lime cement powder added noncement composition showed that the compressive strength increased as the limestone powder was added. It is believed that limestone fine powder played a role of stimulant such as alkali activator in non-cement composition.

• 한국기계가공학회지
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• 제21권7호
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• pp.53-63
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• 2022

Recently, the use of aluminum components in the reduction of the vehicle weight to improve fuel efficiency and reduce carbon dioxide emissions has increased. In the aluminum machining cutting process, hole-making is an important process that accounts for 30% of the machining process. Although many studies have been conducted using the continuously advancing hole processing technology, studies on the machinability of the tool depending on the type of chuck on the workpiece are still lacking. In this study, the machining performance of cemented carbide burnishing drills was compared and analyzed according to chuck type. The burnishing drill was used to create a hole in the AL6061 workpiece, and the surface roughness and dimensional accuracy of the hole were examined according to the type of chuck while monitoring the spindle load.

• 국제학술발표논문집
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• The 4th International Conference on Construction Engineering and Project Management Organized by the University of New South Wales
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• pp.286-291
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• 2011

Onsite usage of construction equipment accounts for a 6.8% of air pollution in Korea. The high concentration of carbon dioxide in such emissions impact not only climate change, but also people's health. However, greenhouse gas emissions from onsite equipment usage have not yet been fully investigated. This study presents a comparative analysis on how much greenhouse gas is generated by various equipment types used in different construction activities. Two ongoing cases which involve a typical road construction project in Korea were selected for the comparison purpose. Greenhouse gas emissions from each onsite equipment usage of the different activities were estimated on the ground of design documents. The estimates were compared and analyzed to derive the main sources of greenhouse gas emissions. The result showed that earthwork constituted the largest part-more than 90%-among work types. Dump truck, bulldozer, and loader were major sources for such emissions. The study results are expected to be used as a basis for reduction of greenhouse gas emission from onsite equipment usage.

• 유기물자원화
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• 제26권2호
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• pp.11-18
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• 2018

다양한 농업 부산물을 열분해하여 바이오차를 생산하고 이를 밭 농경지에 투입함에 따라 토양 화학적 변화와 온실가스 발생량에 대해 비교하여 평가하였다. 실내 인큐베이터 실험으로 항온조건은 미생물 활성이 가장 활발한 조건인 수분보수력 70%, 온도는 $25^{\circ}C$ 조건에서 8주간 실험을 수행하였다. 그 기간 동안 주기적으로 가스시료를 채취하여 온실가스를 각각 분석하였다. 누적 이산화탄소 발생량은 바이오차를 투입하지 않은 대조구에서 $258.6g\;CO_2/m^2$ 그리고 바이오차를 투입한 처리구에서는 207.1에서 $255.2g\;CO_2/m^2$의 범위로 발생하였다. 즉 바이오차가 투입됨에 따라 이산화탄소 발생량이 증가하지 않고 비슷하거나 조금 감소하는 경향을 나타냈다. 아산화질소의 누적 발생량은 대조구에서 $2,890.6mg\;N_2O/m^2$ 그리고 바이오차를 투입한 처리구에서는 379.7에서 $525.2mg\;N_2O/m^2$ 의 범위로 발생하였다. 바이오차가 투입됨에 따라 아산화질소 발생량은 80% 이상 감축할 수 있었다. 따라서 바이오차를 밭 농경지에 적용한다면 아산화질소 발생량을 감축할 수 있는 소재로 활용할 수 가 있을 것이다.