• Journal of Environmental Science International
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• v.32 no.4
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• pp.267-276
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• 2023

In this study, we analyzed seasonal variations in carbon dioxide fluxes, concentrations, and soil temperatures over three years in unvegetated tidal flats in the Beolgyo area. We also investigated the correlations between carbon dioxide fluxes and influencing factors. The average carbon dioxide flux was positive in summer and autumn but negative in winter and spring. A positive correlation was observed between carbon dioxide flux and soil temperature in spring whereas a negative correlation was noted in summer. In summer and autumn, as the soil temperature increased, the carbon dioxide flux decreased. In contrast, in spring and winter, as the soil temperature decreased, the carbon dioxide flux increased. Overall, this study reveals the significant influence of soil temperatures on carbon dioxide fluxes between the surface layer of the tidal flat and atmosphere.

• Journal of the Korean Society of Safety
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• v.27 no.3
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• pp.182-188
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• 2012

In this study we analyzed carbon emissions of leaves of a Pinus densiflora which is vulnerable to a forest fire using the cone calorimeter in order to analyze greenhouse gas emissions from forest fires depending on region and altitude. Fuels were collected from 9 regions[Hongcheon(Gangwon-do), Chungsong(Gyeongbuk-do), Yanhpyeong (Gyeonggi-do), Jecheon(Chungchongbuk-do), Gongju(Chungcheongnam-do), Wuju(Jeollabuk-do), Youngam(Jeollanam-do), Busan and Jeju-do)] and 9 altitudes(80 m, 450 m, 900 m, 1000 m, 1100 m, 1200 m, 1300 m, 1400 m and 1500 m) and then, carbon dioxide and carbon monoxide emissions contained in a weight of 50 g of fuel were analyzed. According to the results, there were differences in carbon emissions by regional groups, as the average carbon dioxide and carbon monoxide emissions in 9 regions were nearly 43.5929 g to 52.8868 g, and 0.8842 g to 3.6422 g, respectively. Busan and Jecheon had relatively higher carbon dioxide emissions and especially, Busan had 1.23 times higher carbon dioxide emissions than Jeju-do. Also, Gongju, Chungcheongnamo Province and Busan had relatively higher carbon monoxide emissions and especially, Gongju and Pusan had relatively higher carbon monoxide emissions and especially, Gongju had 4.12 higher carbon monoxide emissions than Hongcheon. In addition, there were differences in carbon emissions too depending on altitude, since carbon dioxide and carbon monoxide emissions in 9 altitudes were respectively, 40.7015 g to 68.9297 g and 1.3923 g to 12.2918 g. At the altitude of 80m, carbon dioxide and carbon monoxide emissions were respectively, 68.9297 g and 12.2918 g, and at the altitude of 450m, carbon dioxide and carbon monoxide emissions were respectively, 65.5115 g and 11.2497 g. These results show that pine trees at the lower altitude discharge relatively more carbon. It is considered that this analysis on carbon emissions depending on region and altitude can be effectively used for predicting greenhouse gas emissions and establishing statistical data from forest fires in each region and altitude.

• Journal of Bio-Environment Control
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• v.18 no.3
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• pp.285-290
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• 2009

The solid carbon dioxide used for prolongation shelf life of radish sprout that was just 7days. The developed equipment for treated carbon dioxide consisted of solid carbon dioxide evaporated part and high carbon dioxide and low temperature treated part that can hold products. The inner temperature of equipment decreased temperature to below $5^{\circ}C$ from room temperature for 10minutes and carbon dioxide concentration increased to 80%. The radish sprouts treated 4 different conditions that was nontreated condition (control), solid carbon dioxide put into package (CO2-1), solid carbon dioxide treated before storage using the developed equipment (CO2-2), solid carbon dioxide treated before storage and during storage, and sprout packaged with solid carbon dioxide (CO2-3). These radish sprout packaged with $25{\mu}m$ ceramic film stored at $8^{\circ}C$. The high carbon dioxide treatment did not affect the fresh weight loss. The carbon dioxide and oxygen content in package changed 40% and 10%, respectively in CO2-1 and CO2-2 at 1day after treatments. But carbon dioxide content of all treatments was decreased to 5% and stabilized. The high carbon dioxide showed the effect of reduction ethylene production, but did not affect to visual quality and offodor.

• Journal of Korean Society for Atmospheric Environment
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• v.27 no.1
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• pp.117-125
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• 2011

There are many studies reporting the average carbon dioxide levels in various indoor spaces. However, there have been a few studies showing how carbon dioxide concentration varied at many measurement points in one indoor space. In this study, the changes of indoor carbon dioxide concentration at classroom, library, and kindergarten were reported to find its carbon dioxide distribution change at various locations and altitudes. The maximum carbon dioxide concentration of the 3 sites were measured as 2,684, 2,295, and 1,526 ppm, respectively. These values exceeded the guideline concentration of 1,000 ppm for public places. The concentration of carbon dioxide was higher at upper area than lower area, and this is probably due to the rise of warm breathing air generated from students. In the upper area, the carbon dioxide concentration was higher at center area than four corners. However, in the lower area, the carbon dioxide concentration was higher at four corners than center area. Therefore, it could be concluded that the center of upper area is the best place for the installation of ventilation or carbon dioxide removal system.

• Journal of Environmental Science International
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• v.31 no.11
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• pp.951-958
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• 2022

The aim of this study was to determine the optimum level of carbon dioxide to maximize the quality and yields of strawberries cultivated in a greenhouse. Specifically, two strawberry cultivars, namely, 'Seolhyang' and 'Maehyang', were subjected to varying concentrations of carbon dioxide and patterns linked to their productivity were noted. Both cultivars showed improvements across various physical variables (i.e., leaf area, crown diameter, plant height, fresh weight, and dry weight) when carbon dioxide concentrations were at 1,500 ppm. The optimum carbon dioxide concentration for increased fruit yields and quality was 1,000 ppm. When carbon dioxide was at 1,000 ppm the yields of 'Seolhyang' and 'Maehyang' increased by 1.99 and 1.78 times, respectively, compared to control plants. The influence of carbon dioxide on fruit color was negligible. However, the carbon dioxide increased the sugar content and sugar-acid ratio of the experimental fruits compared to control plants. Specifically, the sugar-acid ratio, which is directly related to taste, was at its highest when the concentration of carbon dioxide was at 1,000 ppm (i.e., for both 'Seolhyang' and 'Maehyang'). Overall, the application of carbon dioxide culminated in improved yields and fruit quality for both cultivars of interest.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.181-184
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• 2001

The biological fixation of carbon dioxide using microalgae have many advantages over chemicals and remove carbon dioxide simultaneously. A ketocarotenoid astaxanthin is hyper-accumulated in the green freshwater microalga, Haematococcus pluvialis. In the present study, the combine effects of carbon dioxide concentration and light intensity on the growth of H. pluvilais were investigated. The carbon dioxide concentration above 10% caused a severe inhibition and around 5% is optimal for growth. Adaptation to high concentration of carbon dioxide enhanced the $CO_2$ tolerance. Specific growth rate calculated differently based upon cell number or dry weight because of the distinctive life cycle patterns of H. pluvialis : small-sized motile green cell and thick cell walled red cyst cell. Based on the light dependence of H. pluvialis, internally illuminated air-lift photobioreactor was designed and operated. Gradual increase of light supply gave more active growth and more effective productivity of astaxanthin than constant light supply.

• Journal of The Korean Society of Clinical Toxicology
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• v.5 no.1
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• pp.43-45
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• 2007

Carbon dioxide is the fourth most abundant gas in the earth's atmosphere, and it is widely used in the chemical industry. Solid carbon dioxide is commonly known as dry ice. At low concentration, carbon dioxide appears to have little toxicological effect. At higher concentrations, however, it can produce an increased respiratory rate, tachycardia, cardiac arrhythmia, loss of consciousness, convulsion, and even death. Management of carbon dioxide poisoning requires the immediate removal of an individual from the toxic environment and administration of oxygen. It is important to know the concentration of carbon dioxide to which a patient has been exposed. We report a case of acute poisoning from solid carbon dioxide in a patient presenting with drowsiness and diminished mental capacity when she arrived in the emergency department. She recovered completely after administration of oxygen with conservative treatment.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.2195-2201
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• 2010

High concentration of carbon dioxide in subway cabin may cause various adverse effects on the passengers. Because carbon dioxide is produced by breathing of passengers, carbon dioxide concentration at rush-hours is extremely high. In most cases, the ventilation is not that easy for subway cars due to the high concentration of dust in tunnels. In this study, more practical way to control carbon dioxide in subway car was suggested. The decrease of carbon dioxide concentration was observed when the system was applied to a real subway car. The regenerative method for maintenance-free carbon dioxide control system was also suggested.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.11a
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• pp.205-206
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• 2023

In this study, the characteristics of cement were analyzed using carbon dioxide microbubble water as a mixed water for mineral carbonation of cement materials. Carbon dioxide reacts with the calcium compound of cement to produce calcium carbonate and affects the initial strength improvement. Therefore, in this study, temperature, air content, thermal analysis, and compressive strength tests were conducted to confirm the reaction between cement materials and carbon dioxide. As a result of the measurement, the reaction between cement and carbon dioxide was confirmed in a specimen using carbon dioxide microbubble water as a mixed water, which affected the initial strength improvement.

• Bulletin of the Korean Chemical Society
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• v.32 no.9
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• pp.3377-3381
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• 2011

In this work, the amine grafting treated activated carbons were studied for carbon dioxide adsorbent. The surfaces of activated carbon were functionalized by 3-chloropropyltrimethoxysilane, which was subsequently grafted with amine compounds tris-(2-aminoethyl)amine and tri-ethylenetetramine and subjected to comparison. The surface functional groups of the amine grafted activated carbons were characterized using XPS. The textural properties of the amine grafted activated carbons were analyzed by $N_2$/77 K isotherms. Carbon dioxide adsorption behaviors of the amine grafted activated carbons were examined via the amounts of carbon dioxide adsorption at 298 K and 1.0 atm. From the results, tris-(2-aminoethyl)amine grafted activated carbons showed 43.8 $cm^3$/g of carbon dioxide adsorption while non-treated activated carbons and triethylenetetramine grafted activated carbons showed less carbon dioxide adsorption. These results were thought to be due to the presence of isolated amine groups in the amine compounds. Tris-(2-aminoethyl)amine grafted activated carbons have basic features that result in the enhancement of adsorption capacity of the carbon dioxide molecules, which have an acidic feature.