• 한국신재생에너지학회:학술대회논문집
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• 2006.11a
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• pp.348-351
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• 2006

Bipolar plate, which forms about 50% of the stack cost, is an important core part with polymer electrolyte membrane in PEMFC. Bipolar plates have been commonly fabricated from graphite meterial having high electrical conductivity and corrosion resistance. Lately, many researchers have concentrated their efforts on the development of metallic bipolar plate and stainless steel has been considered as a potential material for metallic bipolar plate because of its high strength, chemical stability, low gas permeability and applicability to mass production. However, it has been reported that its inadequate corrosion behavior under PEMFC environment lead to a deterioration of membrane by dissolved metal ions and an increase in contact resistance by the growth of passive film therefore, its corrosion resistance as well as contact resistance must be improved for bipolar plate application. In this work, several types of coating were applied to 316L and their electrical conductivity and corrosion resistance were evaluated In the simulated PEMFC environment. Application of coating gave rise to low interfacial contact resistances below $19m{\Omega}cm^2$ under the compress force of $150N/cm^2$. It also made the corrosion potential to shift in the posit ive direct ion by 0.3V or above and decreased the corrosion current from ca. $9{\mu}A/cm^2$ to ca. $0.5{\mu}A/cm^2$ in the mixed solution of $0.1N\;N_2SO_4$ and 2ppm HF A coat ing layer under potentiostatic control of 0.6V and $0.75V_{SCE}$ for 500 hours or longer showed some instabilities, however, no significant change in coat Ing layer were observed from Impedance data. In addition, the corrosion current maintained less than $1{\mu}A/cm^2$ for most of time for potentiostatic tests. It indicates that high electrical conductivity and corrosion resistance can be obtained by application of coatings in the present work.

• Journal of the Korean Wood Science and Technology
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• v.45 no.5
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• pp.588-598
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• 2017

Currently, bioethanol, a fuel additive for transportation, is produced mainly by using biomass (first generation) such as corn and sugar canes. First generation biomass can cause various problems in terms of increase in agricultural prices and ethical reasons. To address these problems, a nonedible lignocellulosic biomass can be utilized. Agricultural byproducts such as straw, bagasse, and forest byproducts from the wood processing industry. Therefore, production of wood based bioethanol can be an effective utilization route of second generation biomass, and its raw materials are more abundant than first generation resources. Furthermore, it is possible to secure cheap raw materials. One of the biggest advantages of using biofuels is that it contributes to the reduction of greenhouse gases by minimizing the environmental impact, unlike fossil fuels. In this study, we investigated the greenhouse gas reduction effects that can be achieved through the use of Lignocellulosic bioethanol and government policies on renewable energy currently being implemented in ASEAN countries (Indonesia, Malaysia, Thailand and the Philippines). In these four countries, policies and incentives related to biofuels have been developed. It is expected that the reduction ratio of carbon dioxide emission and the mixed biofuel will be gradually increased in the future.

• Journal of the Korean Vacuum Society
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• v.18 no.6
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• pp.440-446
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• 2009

Indium tin oxide(ITO) substrate is one of the key components of the touch panel and its sputtering process is dependent on the characteristics of various touch panel, such as driving type, size of panel, and the intended use. In this study, we optimized the sputtering condition of ITO film on polycarbonate(PC) by using in-line sputtering method for the application to resistive type touch panel. We varied the $O_2$/Ar gas ratio, sputtering power, pressure and moving speed of substrate to deposit ITO films at room temperature with the base vacuum of $1{\times}10^{-6}\;torr$. The sheet resistance and its uniformity, the transmittance, the thickness of the ITO film on PC substrate are investigated and analyzed. The optimized process parameters are as follows : the sheet resistance is $500{\pm}50\;{\Omega}$/□, the uniformity of sheet resistance is lower than 10%, the transmittance is higher than 87 % at 550nm, and the thickness is about 120~250. The optimized deposition conditions by in-line sputtering method can be applied to the actual mass production for the ITO film manufacturing technology.

• Development and Reproduction
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• v.12 no.1
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• pp.107-112
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• 2008

To investigate the $C_{21}$-steroids produced from maturating oocytes in the longchin goby, Chasmichthys dolichognathus, the oocytes ($0.74{\sim}0.97\;mm$) were incubated with radiolabeled $17{\alpha}$-hydroxyprogesterone ($^3H-17{\alpha}OHP$) for 24 hours. The resulting metabolites were analyzed by thin layer chromatography and identified by gas chromatography-mass spectrometry. Two $C_{21}$-steroids, $17{\alpha}$-hydroxy, $20{\alpha}$-dihydroprogesterone ($17{\alpha}20{\alpha}P$) and $17{\alpha}$-hydroxy, $20{\beta}$-dihydroprogesterone ($17{\alpha}20{\beta}P$), were converted from $^3H-17{\alpha}OHP$ in the maturing oocytes. These two main metabolites were detected at 0.80 mm diameter oocytes or greater. In addition, the effects of these metabolites on in vitro germinal vesicle breakdown (GVBD) were tested. The sensitivity of oocytes to the induction of GVBD was greater at $17{\alpha}20{\beta}P$ than $17{\alpha}20{\alpha}P$. This result showed that $17{\alpha}20{\beta}P$ is a major maturation inducing steroid (MIS) in longchin goby, suggesting $17{\alpha}20{\alpha}P$ may play a role in regulating the oocyte maturation process.

• Asian Journal of Atmospheric Environment
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• v.12 no.3
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• pp.255-273
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• 2018

To develop effective emission abatement strategies for eighteen coal-fired power plants located throughout Korea, power plant emission data and TAPM (The Air Pollution Model) were used to quantify the impact of emission reductions on primary $PM_{10}$ concentrations. TAPM was validated for two separate time periods: a high $PM_{10}$ concentration period from April 7 to 12, 2016, and a low $PM_{10}$ concentration period from June 1 to June 6 2016. The validated model was then used to analyze the impacts of five applicable power plant shut-down scenarios. The results showed that shut-down of four power plants located within the Seoul metropolitan area (SMA) would result in up to 18.9% reduction in maximum $PM_{10}$ concentrations, depending on synoptic conditions. A scenario for the shutdown of a single low stack height with highest-emission power plant located nearest to Seoul showed a small impact on averaged $PM_{10}$ concentrations (~1%) and 4.4% ($0.54{\mu}g/m^3$) decrease in maximum concentration. The scenario for four shutdowns for power plants aged more than 30 years within SMA also showed a highest improvement of 6.4% ($0.26{\mu}g/m^3$ in April) in averaged $PM_{10}$ concentrations, and of 18.9% ($2.33{\mu}g/m^3$ in June) in maximum concentration, showing almost linear relationship in and around SMA. Reducing gaseous air pollutant emissions was also found to be significant in controlling high $PM_{10}$ concentrations, indicating the effectiveness of coreduction of power plant emissions together with diesel vehicle emissions in the SMA. In addition, this study is implying that secondary production process generating $PM_{10}$ pollution may be a significant process throughout most regions in Korea, and therefore concurrent abatement of both gas and particle emissions will result in more pronounced improvements in air quality over the urban cities in South Korea.

• Journal of Animal Science and Technology
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• v.58 no.1
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• pp.4.1-4.7
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• 2016

Background: This study was conducted to evaluate the effects of adding Korean rice wine residue (RWR) in total mixed ration (TMR) on in vitro ruminal fermentation and growth performance of growing Hanwoo steers. Methods: For in vitro fermentation, the experimental treatments were Control (Con: 0 % RWR + TMR), Treatment 1 (T1: 10 % RWR + TMR), and Treatment 2 (T2: 15 % RWR + TMR). The rumen fluid was collected from three Hanwoo steers and mixed with buffer solution, after which buffered rumen fluid was transferred into serum bottles containing 2 g dry matter (DM) of TMR added with or without RWR. The samples were then incubated for 0 h, 12 h, 24 h, or 48 h at $39^{\circ}C$ and 100 rpm. For the in vivo experiment, 27 Hanwoo steers (6 months old) with an average weight of $196{\pm}8.66kg$ were subjected to a 24-week feeding trial. The animals were randomly selected and equally distributed into three groups. After which the body weight, feed intake and blood characteristics of each group were investigated. Results: The pH of the treatments decreased significantly relative to the control during the 12 h of incubation. Total gas production and ammonia nitrogen ($NH_3-N$) was not affected by RWR addition. The total volatile fatty acid (VFA) was lower after 24 h of incubation but at other incubation times, the concentration was not affected by treatments. Feed cost was 8 % and 15 % lower in T1 and T2 compared to control. Blood alcohol was not detected and a significant increase in total weight gain and average daily gain were observed in Hanwoo steers fed with RWR. Conclusion: Overall, the results of this study suggest that TMR amended with 15 % RWR can be used as an alternative feed resource for ruminants to reduce feed cost.

• Applied Chemistry for Engineering
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• v.9 no.2
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• pp.286-293
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• 1998

Two methods were used to enhance the adsorption capacity of activated carbons. One is to impregnate activated carbons with chemical compounds which have a good affinity for $CO_2$. The other is to activate by heat-treating after impregnation with KOH on activated carbons(AC). The chemical compounds impregnated on AC were alkali metal, alkaline earth metal, and transition metal chlorides. The adsorption capacity of $CO_2$ on AC impregnated with these metals was less than that of pure AC. These compounds have not the chemical affinity for $CO_2$ and obstruct the micropore of AC. The experiment of breakthrough for $CO_2$ on AC impregnated with KOH showed the increase of the adsorbed amount of $CO_2$ in influent gases containing water vapor. This means that KOH adsorbes $CO_2$ gas. However, the adsorbents impregnated with KOH had not the reproducibility because of the production of $K_2CO_3$ by the reaction of KOH with $CO_2$. The amount of $CO_2$ adsorbed on the heat-treated AC at $800^{\circ}C$ increased with the amount of impregnation. The adsorption capacity of $CO_2$ was the largest when the ratio of weight of KOH to AC equal to 4. The isosteric heat of adsorption was calculated by the equation of Clausius-Clapeyron form adsorption capacity data of $CO_2$ for the temperature change. In addition, the characteristics of $CO_2$ breakthrough curve were surveyed for the change of flow rate and concentration.

• 한국무역상무학회:학술대회논문집
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• 2006.06a
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• pp.45-72
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• 2006

The Equator Principles are a set of voluntary environmental and social guidelines for ethical project finance. These principles commit banks and other signatories to not finance projects that fail to meet these guidelines. The principles were conceived in 2002 on an initiative of the International Finance Corporation and launched in 2003. Since then, dozens of major banks have adopted the Principles, and with these banks among them accounting for more than three quarters of all project loan market volume the Principles have become the de facto standard for all banks and investors on how to deal with potential social and environmental effects of projects to be financed. While regarding the Principles an important initiative, NGOs have criticised the Principles for not producing real changes in financing activities and for allowing projects to go through that should have been screened out by the Principles, such as the Sakhalin-II oil and gas project in Russia. In early 2006, a process of revision of the principles was begun. The Equator Principles state that endorsing banks will only provide loans directly to projects under the following circumstances: - The risk of the project is categorized in accordance with internal guidelines based upon the environmental and social screening criteria of the International Finance Corporation (IFC). - For all medium or high risk projects (Category A and B projects), sponsors complete an Environmental Assessment, the preparation of which must meet certain requirements and satisfactorily address key environmental and social issues. - The Environmental Assessment report addresses baseline environmental and social conditions, requirements under host country laws and regulations, applicable international treaties and agreements, sustainable development and use of renewable natural resources, protection of human health, cultural properties, and biodiversity, including endangered species and sensitive ecosystems, use of dangerous substances, major hazards, occupational health and safety, fire prevention and life safety, socio-economic impacts, land acquisition and land use, involuntary resettlement, impacts on indigenous peoples and communities, cumulative impacts of existing projects, the proposed project, and anticipated future projects, participation of affected parties in the design, review and implementation of the project, consideration of feasible environmentally and socially preferable alternatives, efficient production, delivery and use of energy, pollution prevention and waste minimization, pollution controls (liquid effluents and air emissions) and solid and chemical waste management. - Based on the Environmental Assessment, Equator banks then make agreements with their clients on how they mitigate, monitor and manage those risks through an 'Environmental Management Plan'. Compliance with the plan is required in the covenant. If the borrower doesn't comply with the agreed terms, the bank will take corrective action, which if unsuccessful, could ultimately result in the bank canceling the loan and demanding immediate repayment. - For risky projects, the borrower consults with stakeholders (NGO's and project affected groups) and provides them with information on the risks of the project. - If necessary, an expert is consulted. The Principles only apply to projects over 50 million US dollars, which, according to the Equator Principles website, represent 97% of the total market. In early 2006, the financial institutions behind the Principles launched stakeholder consultations and negotiations aimed at revising the principles. The draft revised principles were met with criticism from NGO stakeholders, who in a joint position paper argued that the draft fails by ignoring the most serious critiques of the principles: a lack of consistent and rigorous implementation.

• Journal of the Korea Organic Resources Recycling Association
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• v.9 no.4
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• pp.111-116
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• 2001

As part of the recycling methods, residual food through the anaerobic fermentation process was decomposed into methane gas and fermentation liquid. The research was conducted to measure the effect of application of fermentation liquid on chemical properties of soil and plant growth according to application rate and separate manure at the base of nitrogen in fermentation liquid. The fermentation liquid contained 0.52% nitrogen was applied in treatments by standard fertilizer. The treatments were composed of the control only with chemical fertilizer and N-50, N-100-4, N-100-8 were each of applied with 50, 100(6 times), 100(3 times)% of fermentation liquid contrast to standard fertilizer. Properties of fermentation liquid was high EC because of waster soluble organic compounds as well as much of salts and also contained a lot of suspended solid. The changes of soil chemical properties little occurred in before and after of experiment but EC and content of ex. Ca in soil were increased. Fresh weigh in treatments applied with fermentation is high than that of control but the difference between treatments little showed. The above result means if fermentation liquid be used instead of chemical fertilizer the volume of used fermentation liquid will be reduced by 50% of present standard fertilizer.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.10
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• pp.1456-1463
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• 2011

A total of 629 Duroc${\times}$Landrace${\times}$Large White crossbred pigs were utilized in three experiments (Exp. 1, 222 pigs weighing $25.6{\pm}2.0\;kg$ BW; Exp. 2, 216 pigs weighing 5$6.2{\pm}4.3\;kg$ BW; Exp. 3, 191 pigs weighing $86.4{\pm}4.6\;kg$ BW) conducted to determine the effects of fermented potato pulp on performance, nutrient digestibility, carcass traits and plasma parameters in growingfinishing pigs. Each experiment lasted 28 d. The pigs were assigned to one of two corn-soybean meal-based diets containing 0 or 5% fermented potato pulp. The inclusion of fermented potato pulp increased weight gain (p<0.05) in experiments 1 and 2 and increased feed intake (p<0.05) in experiment 2. Feed conversion was improved (p<0.05) in experiment 2 and showed a tendency to improve (p<0.10) in experiments 1 and 3 when pigs were fed fermented potato pulp. Fermented potato pulp increased (p<0.05) dry matter digestibility in experiments 1 and 3 and energy digestibility in experiment 2. Feeding fermented potato pulp decreased plasma urea nitrogen (p<0.05) and alanine aminotransferase (p<0.05) in experiments 1 and 2, while plasma aspartate aminotransferase was decreased (p<0.05) in experiment 3. Dietary fermented potato pulp did not affect the carcass characteristics of finishing pigs. Feeding fermented potato pulp reduced (p<0.05) fecal ammonia concentration in all three experiments. In conclusion, feeding growing-finishing pigs diets containing 5% fermented potato pulp improved weight gain and feed conversion without any detrimental effects on carcass traits. The improvements in pig performance appeared to be mediated by improvements in nutrient digestibility.