• Analytical Science and Technology
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• v.8 no.4
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• pp.869-876
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• 1995

The active sites of the nickel and iron-containing enzyme, carbon monoxide dehydrogenase (CODH) from clostridium thermoaceticum were investigated using Electron Paramagnetic Resonance (EPR) technique. CODH exhibits several spectral features called NiFeC, $g_{ave}=1.82$, $g_{ave}=1.86$. FCII signals which are originated from different clusters in this enzyme. CODH is know to catalyze two different kinds of reactions - acetyl-CoA synthesis and CO oxidation. The acetyl-CoA synthesis activity can be followed by monitoring CO/acetyl-CoA exchange. The addition of 1,10-phenanthroline (phen) to CODH selectively destroyed the CO/acetyl-CoA exchange activity and eliminated the NiFeC signal completely. CO oxidation activity and other EPR signals were unaffected. Such behavior demonstrates that CODH has two distinct active sites and that the NiFe complex is only responsible for the CO/acctyl-CoA exchange activity. Phen caused the removal of only 30% of Ni in the NiFe complex ($0.3Ni/{\alpha}{\beta}$) as shown by the quantitative metal analysis. The phen-treated CODH could be reactivated fully by incubation In $Ni^{2+}$ solution. Radioactive $^{63}Ni^{2+}$ was used to quantitate the amount of the $Ni^{2+}$ incorporated into phen-treated enzyme and showed that the amount was the same as the removed by the phen treatment. i.e. $0.3Ni/{\alpha}{\beta}$. This indicates that only 30% of NiFe complexes are labile and responsible for the CO/acctyl-CoA exchange activity, the other 70% are non-labile and have no exchange activity. This is the first clear evidence that the NiFe complex is heterogencous and labile and non-labile Ni sites arc interacting differently with substrates and chelating agents like phen.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.05a
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• pp.261-266
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• 2003

This study is to investigate the heating value and noxious gases generation such as CO, NO and $SO_2$ known as dangerous gas for human from specimen made of cement and lightweight aggregate. The most quanity of CO gas is generated in EPS(Expanded Poly Styrene), core of commercial sandwich panel. Although specimens mainly composed of cement discharged the relatively less CO gas than organic core such as EPS, specimens which SBR was added discharged the very much amount of CO gas similar to EPS and especially, specimens including foaming agent, gas foaming agent or redipersible powder of VA/VeoVa showed the good properties in the generation of CO gas. From the standpoint of the generation of NO and $SO_2$ gas, both the core of commercial sandwich panel such as EPS, Glass wool and specimens made with polymer dispersion such as St/BA and SBR discharge the very much amount of NO and $SO_2$ gas in comparison of the other specimens. From this study, it was confirmed that organic materials such as core of commercial sandwich panel dischared much more noxious gas than specimens composed of cement and inorganic lightweight aggregate.

• Journal of Korean Society of Water and Wastewater
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• v.11 no.2
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• pp.50-64
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• 1997

Life cycle assessment (LCA) on total sewage sludge treatment system from thickening to incineration and melting was performed for estimating global environmental impact as $CO_2$. In general, the life cycles of actual treatment facilities consist of construction, operation and dismantlement. In this study, the amount of $CO_2$ produced from both whole and each life cycle step of currently used unit sludge treatment processes were calculated by inventory analysis. In addition, in the all processes investigated in this study, individual $CO_2$ production unit (CPU), i.e. total produced $CO_2$ by treating a unit weight of sludge was also calculated. By using the CPU matrix of the unit processes, it was possible to simulate the $CO_2$ production for any type of complex-system as well as to trace a dominant cause of $CO_2$ production in each process. Four selected alternatives examined here, each involve the same disposal way but differ substantially in the $CO_2$ exhaust.

• Journal of Climate Change Research
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• v.7 no.2
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• pp.157-167
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• 2016

This study aims to evaluate the effect of shortened final cutting age by estimating future $CO_2$ absorption in each different scenarios based on each final cutting ages before and after shortening. We used $5^{th}$ Forest Type Map and Forest Yield Table to obtain information to estimate $CO_2$ absorption of forest. We also designed a simulated future scenarios from 2010 to 2100 which repeats cutting and reforestation according to respected each final cutting ages. As the result, number of cuttings and total amount of $CO_2$ absorption of forest were increased with shortened final ages. Total cutting times increased up to 2 in both minimum and maximum amount for Quescus spp. and Larix kaempferi. Maximum number of cutting of Pinus densiflora and minimum number of Pinus koraiensis increased by 1. Total $CO_2$ absorption increased 12％ for Quercus spp. which had the largest number of increase in cutting times, while total $CO_2$ absorption of Pinus koraiensis only increased by 1％. The result could be used to evaluate the changes in forest management plans and policies and then develop optimal final age for efficient sustainable forest management plans.

• Health Policy and Management
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• v.17 no.1
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• pp.1-27
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• 2007

This study is designed to estimate an appropriate level of patient's cost-sharing for oriental medical services in the Korean National Health Insurance. The findings of this study can be summarized as follows: 1) The current co-payment system for oriental medical services does not reflect its cost structure in clinical practice due to inconsistency of cost-sharing plan in the NHI. 2) Both oriental medical institutions and their patients, as a result, are at a relative disadvantage in financial burden, compared with other services. 3) The substantial proportion of patients' cost-sharing depends on the amount of co-payment and the range of medical cost that a flat rate is applied to. 4) The extension of the range doesn't make any substantial decrease in patient's cost-sharing. 5) The fixed amount of co-payment is more sensitive than a range to total variations of patient's cost-sharing. Based on the above, the budget impacts of a new co-payment system were estimated for each co-insurance rate, according to given scenarios. The results range from -59 billion Won (-8.5%) to 16 billion Won(2.3%).

• Bulletin of the Korean Chemical Society
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• v.13 no.1
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• pp.20-22
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• 1992

Treatment of benzal chloride, alcohol, $K_2CO_3$, and a catalytic amount of $Co_2(CO)_8$ at $80^{\circ}C$ for 24 hours under 30 atm of CO gave the corresponding alkyl phenylacetate in good yield.

• Journal of Climate Change Research
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• v.4 no.1
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• pp.27-39
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• 2013

In this study, the anthracite coal being used as fuel in Korea were classified into different types. These types include the domestically produced anthracite, imported anthracite used as raw material, and imported anthracite used as fuel. Each of the calorific values and greenhouse gas emission factors were calculated. The calculation of greenhouse gas emission factors resulted in the domestically produced anthracite as $111,477{\pm}4,508kg\;CO_2/TJ$, the imported anthracite used as raw material as $108,358{\pm}4,033kg\;CO_2/TJ$, and anthracite used as fuel was displayed as $103,927{\pm}8,367kg\;CO_2/TJ$. Additionally, the amount of greenhouse gas emission based on these calculated emission factors was displayed as $6,216,942ton\;CO_2$, which resulted as 12.7% lower than the green house gas emission amount which was calculated without distinguishing anthracite coal in details. Therefore, collecting activity data through a detailed classification of anthracites facilitate a more accurate calculation of greenhouse gas emission amount compared to collecting activity data through combination. Furthermore, since the anthracite coal used domestically possesses characteristics differing from the anthracite coal proposed by the IPCC, anthracite coal should be classified for each purpose and calculated for the improvement of the national greenhouse gas inventory.

• Journal of Korean Society on Water Environment
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• v.23 no.5
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• pp.665-675
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• 2007

In-situ Air Sparging (IAS, AS) is a remediation technique in which organic contaminants are volatilized from saturated zone to unsaturated layer. This study focuses on the removal and interaction of Volatile Organic Compounds (VOCs) and $CO_2$, and Total Petroleum Hydrocarbon (TPH) in saturated and unsaturated, and air space zone on the unsaturated soil surface. Soil sparging temperature of hot air has risen to $34.9{\pm}2.7^{\circ}C$ from $23.0{\pm}1.9^{\circ}C$ for 36 days. At the diffusing point, fluid TPH concentrations were reduced to 78.7% of the initial concentration in saturated zone when hot air was sparged. The TPH concentrations were decreased to 66.1% for room temperature air sparging. The amount of VOCs for hot air sparging system, in air space, was approximately 26% larger than constant air sparging system. The amount of $CO_2$ was 4,555 mg (in unsaturated zone) and 4,419 mg (in air space) when hot air was sparged was 3,015 mg (in unsaturated zone) and 3,634 mg (in air space) for room air temperature in the $CO_2$ amount. The removals of VOCs and biodegradable $CO_2$ through the hot air sparging system (modified SVE) were more effective than the room temperature air sparging. The regression equation were $Y=976.4e^{-0.015{\cdot}X}$, $R^2=0.98$ (hot air sparging) and $Y=1055e^{-0.028{\cdot}X}$, $R^2=0.90$ (room temperaure air sparging). Estimated remediation time was approximately 500 days, if final saturated soil TPH concentration was set to 1.2 mg/L application of tail effect.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.11a
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• pp.63-64
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• 2011

Recently, due to global warming, CO₂ emissions is one of the global issues over all areas including construction industry. In Korea, apartment housing has large ratio of building construction and its CO₂ emissions during the operation and maintenance has the most large amount of tatal life cycle of apartment housing. However, there are rare research related to this subject. So, this study investigates the CO₂ emissions of domestic apartment housing during the operation and maintenance. In the future, the results of this study can be utilized in further study to decrease CO₂ emissions strategy.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.05a
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• pp.35-36
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• 2018

According to the nation's greenhouse gas emission statistics, greenhouse gas emissions have been stiffly increasing. Accordingly, the importance of CO₂ reduction is more getting focused over the world. This trend makes the construction equipment be considered as a major target of reduction due to the large volume of emission. This study suggests the feasible methodology for estimating CO₂ emission from construction equipment and for being easily applied on the job sites. The methodology is based on the collection from the segmented CO₂ emission information of construction equipment. This study allows site personnels to estimate the total amount of CO₂ and to take appropriate actions for reasching the environmental regulations.