• Geophysics and Geophysical Exploration
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• v.13 no.4
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• pp.388-396
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• 2010

As a part of basic studies on monitoring and saturation estimation of carbon dioxide ($CO_2$) storage using resistivity survey, laboratory experiment has been conducted to measure the change of the electrical resistivity through repeated experiments of supercritical $CO_2$ and brine water injection into homogeneous and heterogeneous sandstones. The $CO_2$ saturation is estimated by using resistivity index based on the resistivity measurements. The experimental results of two types of sandstones show that the effect of pore structure in the rock and the effect of contained clay minerals in the rock can be affected to calculate the $CO_2$ saturation. The result can be useful to evaluate the $CO_2$ saturation based on resistivity survey at the site where $CO_2 sequestrates.

• Transactions of the Korean hydrogen and new energy society
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• v.4 no.2
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• pp.17-22
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• 1993

$ErCo_2$화합물에서 Co를 천이원소로 10%만큼 치환한 $Er(Co_{0.9}M_{0.1})_2$화합물(M=Cr, Mn, Fe, Ni, Cu)의 비정질화 온도를 측정해서 수소유기 비정질화에 영향을 미치는 인자에 대해 살펴보았다. 비정질화 온도는 치환원소의 원자반경과 비례함을 알 수 있었다 그러므로 $ErCo_2$ Laves 화합물에서 수소유기 비정질화에 영향을 미치는 인자는 확산과 밀접한 연관이 있는 원자의 크기임을 알 수 있다.

• Korean Chemical Engineering Research
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• v.49 no.3
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• pp.372-380
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• 2011

Char gasification is affected by operating conditions such as reaction temperature, reactants gas partial pressure, total system pressure and particle size in addition to chemical composition and physical structure of char. The aim of the present work was to characterize the effect of coal particle size on $CO_{2}$ gasification of chars prepared from two different types of bituminous coals at different reaction temperatures(1,000-$1,400{^{\circ}C}$). Lab scale experiments were carried out at atmospheric pressure in a fixed reactor where heat was supplied into a sample of char particles. When a flow of $CO_{2}$(40 vol%) was delivered into the reactor, the char reacted with $CO_{2}$ and was transformed into CO. Carbon conversion of the char was measured using a real time gas analyzer having NDIR CO/$CO_{2}$ sensor. The results showed that the gasification reactivity increased as the particle size decreased for a given temperature. The sensitivity of the reactivity to particle size became higher as the temperature increases. The size effects became remarkably prominent at higher temperatures and became a little prominent for lower reactivity coal. The particle size and coal type also affected reaction models. The shrinking core model described better for lower reactivity coal, whereas the volume reaction model described better for higher reactivity coal.

• Journal of the Korean Society for Marine Environment & Energy
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• v.9 no.4
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• pp.243-252
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• 2006

Influence of the increasing carbon dioxide concentration in seawater on various marine organisms is assessed in this article with regard to the impacts of anthropogenic $CO_2$ introduced into surface or deep oceans. Recent proposals to sequester $CO_2$ in deep oceans arouse the concerns of adverse effects of increased $CO_2$ concentration on deep-sea organisms. Atmospheric introduction of $CO_2$ into the ocean can also acidify the surface water, thereby the population of some sensitive organisms including coral reefs, cocolithophorids and sea urchins will be reduced considerably in near future (e.g. in 2100 unless the increasing trend of $CO_2$ emission is actively regulated). We exposed bioluminescent bacteria and benthic amphipods to varying concentrations of $CO_2$ and also pH for a short period. The ${\sim}l.5$ unit decrease of pH adversely affected test organisms. However, amphipods were not influenced by decreasing pH when HCl was used for the seawater acidification. In this article, we reviewed the biological adverse effects of $CO_2$ on various marine organisms studied so for. Theses results will be useful to predict the potential risks of the increase of $CO_2$ concentrations in seawater due to the increase of atmospheric $CO_2$ emission and/or sequestration of $CO_2$ in deep oceans.

• Plant Journal
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• v.13 no.2
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• pp.34-38
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• 2017

To reduce global warming, there are so many studies, investments and efforts. The Post Combustion $CO_2$ Capture technology is one of these efforts. But the technologies are having trouble with reducing operating prices. And CCS technology which is using amine solvent uses high price amine solvent. There is solvent losses naturally when operating plant. The solvent loss makes operating and maintenance price higher. In this study, how the washing column of treated flue gas affects the losses of amine solvent and operating was studied.

• Fire Science and Engineering
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• v.16 no.4
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• pp.33-43
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• 2002

To analyze the effect of fire plume on the characteristics of air flow and $CO_2$, extinguishant transfer when extinguishant is injected into a closed space similar to a marine engine room with fire plume, a numerical simulation on a space was performed. Flow fields and $CO_2$, concentration fields are calculated according with the variation of the location of nozzles. In all cases excepting the case of all nozzles located in the right side of ceiling, an counterclockwise & clockwise recirculation flow was found in the region of the right and left side of the nozzle on the second floor and such a recirculation flow greatly affected mass transfer and the diffusion process of $CO_2$, extinguishant. In the region of the first floor with fire plume, the diffusion process of $CO_2$, extinguishant was in agreement with the extension process of recirculation flow. It is considered that the result of this study can be useful to designing the arrangement of nozzles for the $CO_2$ fire fighting equipments in a marine engine room.

• Journal of Applied Biological Chemistry
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• v.64 no.4
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• pp.351-356
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• 2021

Changing environmental conditions can affect plant growth by influencing water and nutrient transport and photosynthesis. Plant physiological responses under changing environmental conditions can be non-destructively monitored using electrodes as plant induced electrical signal (PIES). Objective of the study was to monitor PIES in response to increased CO₂ and decreased photosynthetic photon flux density (PPFD). The PIES increased during day time when transpiration and photosynthesis occurs and monitored CO₂ concentration was negatively correlated to the PIES. Enhanced CO₂ concentration slightly reduced PIES, but the effect of increased CO₂ was limited by light intensity. The effect of reduced PPFD was not appeared immediately because water and nutrient transport was not promptly affected by the light. The study was conducted to evaluate short-term effect of increasing CO₂ and decreasing PPFD, hence proline content and chlorophyll fluorescence was not significantly affected by the conditions.

• Korean Journal of Environment and Ecology
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• v.30 no.1
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• pp.130-134
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• 2016

How does $CO_2$ affect on the stomatal mechanism? The mechanism of stomatal opening by $CO_2$ is not clear as it is difficult to see $CO_2$ effect on light-induced stomatal opening. Furthermore, stomata may react differently according to the concentration of $CO_2$. The significance of the possible endogenous rhythms must consider to understand on $CO_2$-related response. It is clear that $CO_2$ has an effect on the accumulation of osmotic materials which determines the degree of stomatal apertures because it is known that stomata open in the condition of the reduced $CO_2$ concentration. However, it is not fully understood how $CO_2$ leads to the stomatal opening. It has been thought that $CO_2$ can not affect on the ion fluxes which determines the increase of osmotic potential in guard cells. However, in this study, the changes of guard cell membrane permeability by $CO_2$ have been focused on. There are many reports that $CO_2$ related reactions are dominant when the leaf is exposed to certain a mount of $CO_2$. The hypothesis of the stomatal opening by light is based on the increase of osmotic materials in guard cells including $K^+$, $Cl^-$, sucrose and $malate^{2-}$. It was reported that $CO_2$ induced a big hyperpolarization indicating that $H^+$ was extruded to the cell outside. It was also found that $CO_2$ caused guard cell membrane hyperpolarization in the intact leaf up to 3 or 4 times higher than that of light induced membrane hyperpolarization. These results represent that $CO_2$ can affect on the change of physical characteristics which affects on the change of the membrane permeability.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.6
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• pp.1185-1194
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• 2011

This study was carried out to estimate carbon emission using LCA (Life Cycle Assessment) and to establish LCI (Life Cycle inventory) DB for lettuce production system in protected cultivation. The results of data collection for establishing LCI DB showed that the amount of fertilizer input for 1 kg lettuce production was the highest. The amounts of organic and chemical fertilizer input for 1 kg lettuce production were 7.85E-01 kg and 4.42E-02 kg, respectively. Both inputs of fertilizer and energy accounted for the largest share. The amount of field emission for $CO_2$, $CH_4$ and $N_2O$ for 1 kg lettuce production was 3.23E-02 kg. The result of LCI analysis focused on GHG (Greenhouse gas) showed that the emission value to produce 1 kg of lettuce was 8.65E-01 kg $CO_2$. The emission values of $CH_4$ and $N_2O$ to produce 1 kg of lettuce were 8.59E-03 kg $CH_4$ and 2.90E-04 kg $N_2O$, respectively. Fertilizer production process contributed most to GHG emission. Whereas, the amount of emitted nitrous oxide was the most during lettuce cropping stage due to nitrogen fertilization. When GHG was calculated in $CO_2$-equivalents, the carbon footprint from GHG was 1.14E-+00 kg $CO_2$-eq. $kg^{-1}$. Here, $CO_2$ accounted for 76% of the total GHG emissions from lettuce production system. Methane and nitrous oxide held 16%, 8% of it, respectively. The results of LCIA (Life Cycle Impact assessment) showed that GWP (Global Warming Potential) and POCP (Photochemical Ozon Creation Potential) were 1.14E+00 kg $CO_2$-eq. $kg^{-1}$ and 9.45E-05 kg $C_2H_4$-eq. $kg^{-1}$, respectively. Fertilizer production is the greatest contributor to the environmental impact, followed by energy production and agricultural material production.

• Korean Journal of Food Science and Technology
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• v.32 no.3
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• pp.668-673
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• 2000

The influence of storage atmosphere on ethylene production, quality attributes and storage injury of 'Tsugaru' apples was investigated. Apples were stored in 1% $O_2+1%\;CO_2,\;1%\;O_2+3%\;CO_2,\;3%\;O_2+1%\;CO_2,\;3%\;O_2+3%\;CO_2$ and air at $0^{\circ}C$ for 5 months. Ethylene production was more suppressed by 1% $O_2$ than 3% $O_2$ atmospheres regardless $CO_2$ levels. The loss of flesh firmness and the decrease of titratable acidity were not significantly different among the storage atmospheres until 3 months of storage but more retarded by 1% $O_2$ than 3% $O_2$ atmospheres thereafter. Soluble solid content was unaffected by the storage atmosphere, but the content tended to be increased until 2 months of storage and then not varied. Ethanol content increased up to a peak level followed by a gradual loss during storage in CA but increased continuously in air. In the sensory evaluation after storage for 5 months, hardness, tartness and overall acceptability of apples stored in 1% $O_2$ atmospheres were significantly higher than those stored in the others. There was no fruit injury or off-flavor production resulting from the 1% $O_2$ atmospheres. The incidence of bitter pit was reduced as storage $O_2$ level decreased. The results show that the optimum conditions of CA storage for 'Tsugaru' apples are $0^{\circ}C$ and 1% $O_2+1{\sim}3%\;CO_2$.