• Korean Journal of Organic Agriculture
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• v.23 no.4
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• pp.923-938
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• 2015

This study was conducted to serve as the basis for establishing a standard cultivation, which enhances the alternative utilization of pig manure, a major cause of environmental pollution, by finding a means for reducing greenhouse gas emissions for eco-friendly cultivation. In a laboratory, $CH_4$ and $CO_2$ emission patterns were investigated corresponding to incremental pig manure treatments in paddy soil. The emissions peaked 12 to 27 days after manure application in the 100~400% applications. It was found that increasing applications of pig manure resulted an increase in $CH_4$ and $CO_2$ emissions. Additionally, application of more than 150% emitted a larger amount of these gasses than applying chemical fertilizer. However, the test application of 100% pig manure emitted a smaller amount of $CH_4$ and hence Global Warming Potential (GWP) than those emitted by chemical fertilizer. If appropriate amount of fertilization is applied in compliance with the standard application rate, the pig manure may be effective in reducing greenhouse gas emissions and the soil environment made more favorable than with the use of chemical fertilizer.

• Journal of the Korean Ceramic Society
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• v.45 no.8
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• pp.493-496
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• 2008

Composite electrodes consisting of $CoMnO_2$ and carbon nanofibers(vapor grown carbon nanofiber, VGCF) with high electrical conducivity($CoMnO_2$/VGCF) were prepared on a porous nickel foam substrate as a current collector and their supercapacitive properties were investigated using cyclic voltammetry in 1 M KOH aqueous solution. The $CoMnO_2$/VGCF electrode exhibited high specific capacitance value of 630 F/g at 5 mV/s and excellent capacitance retention of 95% after $10^4$ cycles, indicating that the used VGCF played the important roles in reducing the interfacial resistance in the composite electrode to improve supercapacitive performance.

• Food Science and Preservation
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• v.1 no.1
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• pp.29-36
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• 1994

This study was carried out for the establishment of optic harvest date and storage condition of 'Fuji' apple for CA storage. Apples were picked at 10 day intervals from 17 Sept to 27 Oct.. Apples were analyzed for respiration rata, weight flesh firmness, titratable acidity, soluble solid, total sugar, reducing sugar, surface color and thiault value. In 1990, the optimal harvest season could be judged between 17 Oct. and 27 Oct. from the results of respiration rate rise and change of quality properties. Apples harvested on 27 Oct. wert stored at 2$^{\circ}C$ and 90~95% RH in 1%O2 + 3%CO2, 3%O2 + 3%CO2 and air for 9 months. After 9 months of storage, apples kept in CA storages had beater quality than apples kept in refrigeration storage. Especially, apples kept in 1%O2, + 3%CO2 were fumer and more acid than those kept in 3%O2 + 3%CO2 At the sensory evaluations, apples stored in CA were rated higher quality than apples stared refrigeration.

• Journal of Radiation Protection and Research
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• v.42 no.3
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• pp.141-145
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• 2017

Background: The concrete walls inside the vaults of cyclotron facilities are activated by neutrons emitted by the targets during radioisotope production. Reducing the amount of radioactive waste created in such facilities is very important in case they are decommissioned. Thus, we proposed a strategy of reducing the neutron activation of the concrete walls in cyclotrons during operation. Materials and Methods: A polyethylene plate and B-doped Al sheet (30 wt% of B and 2.5 mm in thickness) were placed in front of the wall in the cyclotron room of a radioisotope production facility for pharmaceutical use. The target was Xe gas, and a Cu block was utilized for proton dumping. The irradiation time, proton energy, and beam current were 8 hours, 30 MeV, and $125{\mu}A$, respectively. To determine a suitable thickness for the polyethylene plate set in front of the B-doped Al sheet, the neutron-reducing effects achieved by inserting such sheets at several depths within polyethylene plate stacks were evaluated. The neutron fluence was monitored using an activation detector and 20-g on de Au foil samples with and without 0.5-mm-thick Cd foil. Each Au foil sample was pasted onto the center of a polyethylene plate and B-doped Al sheet, and the absolute activity of one Au foil sample was measured as a standard using a Ge detector. The resulting relative activities were obtained by calculating the ratio of the photostimulated luminescence of each foil sample to that of the standard Au foil. Results and Discussion: When the combination of a 4-cm-thick polyethylene plate and B-doped Al sheet was employed, the thermal neutron rate was reduced by 78%. Conclusion: The combination of a 4-cm-thick polyethylene plate and B-doped Al sheet effectively reduced the neutron activation of the investigated concrete wall.

• 한국연소학회:학술대회논문집
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• 2007.05a
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• pp.54-59
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• 2007

In a view of capturing $CO_2$ as a greenhouse gas, an experimental study was conducted on the combustion characteristics of pulverized coal in $O_2$/$CO_2$ environment using TGA/DSC and DTF facilities. The effects of gas composition and concentration on the processes of devolatilization and char burning experienced by coal particles in combustion furnace and on the concentration of products such as $CO_2$, CO and $NO_x$ were observed using TGA/DSC and DTF respectively. As results, it were found that the rate of devolitilation is nearly independent on the $O_2$ concentration if it is over 20% but the char burning rate is a sensitive function of $O_2$ percent, and the two rates can be controlled by $O_2$ concentration in order to be similar with those of air combustion case. It was also found that high concentration $CO_2$ can be captured by oxy-coal combustion and high concentration of CO and low value of $NO_x$ are exhausted in that case. Additionally, NO reducing reaction by CO with char as catalyst was observed and a meaningful results were obtained.

• Clean Technology
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• v.14 no.4
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• pp.281-286
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• 2008

Absorption rate of carbon dioxide was measured in the aqueous polyacrylamide (PAA) solution containing triethanolamine (TEA) of $0{\sim}2.0\;kg\;mol/m^3$ in a flat-stirred vessel with an impeller of 0.05 m and agitation speed of 50 rpm at $25^{\circ}C$ and 101.3 kPa. The chemical absorption rate of $CO_2$ was estimated by mass transfer mechanism based on the film theory using the physicochemical properties containing the liquid-side mass transfer coefficient of $CO_2$ and the kinetics of reaction between $CO_2$ and TEA to compare with the measured rate. The aqueous PAA solution acted as a reducing agent by viscoelastic property of non-Newtonian liquid based on the same viscosity of the solution.

• Applied Chemistry for Engineering
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• v.23 no.6
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• pp.572-576
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• 2012

This study presents the $CO_2$ methanation reaction on Pt catalysts for reducing the amount of $CO_2$, one of greenhouse gases. The AlO(OH) of $Al_2O_3$precusor was used as a support via a thermal treatment and the Pt was used as an active metal. In XRD results, it was confirmed that the Pt was well dispersed and the support existed as the gamma $Al_2O_3$phase. The $Pt/Al_2O_3$ catalyst calcined at $600^{\circ}C$ showed the highest conversion efficiency and selectivity.

• Journal of the Korean Society of Combustion
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• v.22 no.1
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• pp.14-22
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• 2017

Co-firing of renewable fuel in coal fired boilers is an attractive option to mitigate $CO_2$ emissions, since it is a relatively low cost option for efficiently converting renewable fuel to electricity by adding biomass as partial substitute of coal. However, it would cause reducing plant efficiency and operational flexibility, and increasing operation and capital cost associated with handling and firing equipment of renewable fuels. The aim of this study is to investigate the effects of biomass co-firing on $CO_2$ emission and capital/operating cost. Wood pellet, PKS (palm kernel shell), EFB (empty fruit bunch) and sludge are considered as renewable fuels for co-firing with coal. Several approaches by the co-firing ratio are chosen from previous plant demonstrations and commercial co-firing operation, and they are evaluated and discussed for $CO_2$ reduction and cost estimation.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.1312-1316
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• 2009

Growing interest in $CO_2$ capturing from industrial processes and storage in underground formations is emerging from commitments in reducing $CO_2$ emissions manifested in the Kyoto Protocol. In this paper, $CO_2$ liquefaction system is treated in focus of liquefaction efficiency & production rate. Presently $CO_2$ is transported in ships or trucks at a pressure of 14-20 bar. Considering this, the liquefaction pressures of 20, 15, 6.5 bar are selected. Compressor work and cooling capacity are calculated and compared. In order to investigate the effect of intercooling, the compressed gas after compressor work is cooled by ambient air or seawater. In case of applying the intercooling to the system, consuming energy can be saved larger than 20%. In the lower liquefaction pressure, the more $CO_2$ can be obtained due to higher density. In the liquefaction pressure of 6.5 bar, its $CO_2$ production is about 35% higher than that of the system with the liquefaction pressure, 20 bar.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.60-60
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• 2010

CO2 reforming of methane (CRM) based on Ni catalysts was studied using temperature programmed reaction (TPR). The onset temperature of the CRM reaction was increased in a repeated TPR experiments. X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy showed formation of graphite structures on Ni during CRM reaction, which deactivate Ni-surfaces. Attempts were made for inhibiting deactivation of Ni surfaces and reducing onset-temperature of the CRM reaction by various surface modification techniques, which will be presented in this poster.