• Journal of Energy Engineering
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• v.23 no.3
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• pp.72-81
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• 2014

Intergovernmental Panel on Climate Change(IPCC) suggested the three methodology, Tier 1/2/3, considering with the accuracy and difficulty of greenhouse gas emission statistics according to the report determined as the international criterion. In Korea, the existing inventory building was made by the Top-down approach applying with the emission factors for transportation in the entire energy consumption, the emission factors were investigated under the domestic traffic situation which did not reflect by the continuing increase of vehicle and the change of road section. From the suggestion of IPCC, which it is estimated that the emission estimation of $CO_2$ in greenhouse gas emission could be calculated more accurate by the carbon content according to the fuel, the establishment of measures to respond to climate change from the latest greenhouse gas emissions statistics will be able to improve the accuracy of national statistics using monthly or seasonally the analysis of carbon content about the transportation fuels.

• The Korean Journal of Food And Nutrition
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• v.28 no.5
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• pp.829-834
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• 2015

To decrease excessive sugar intake, and increase vegetable and calcium intake, we manufactured sugar free fruit-vegetable jam containing calcium and fructo-oligosaccharide to substitute for sucrose. We evaluated jam for physico-chemical and sensory properties. When the amount of apple was replaced with the amount of kale, $^{\circ}brix$ decreased, whereas there were no significant changes in pH. As the amount of kale increased, lightness and yellowness increased. However redness did not show trend to increase or decrease. In the texture profile analysis, hardness, springiness, cohesiveness, gumminess and chewiness significantly decreased with increased amount of kale, but adhesiveness gradually increased. The sensory parameters including taste, flavor, color, spreadability and overall acceptance of jam added 10.0~12.0% amount of kale were the highest acceptance. As the amount of kale added in the jam, sensory properties decreased. In general, when sugar free fruit-vegetable jam was manufactured, apple and kale ratio of 3:1 or 4:1 was considered appropriate.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.4
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• pp.429-437
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• 2006

To establish the efficient treatment technology of chemical cleaning wastewater from power plant, several AOPs($UV/H_2O_2,\;UV/TiO_2/H_2O_2$, Photo-Fenton oxidation) were investigated. Treatment efficiencies and the electrical energy requirements based on the EE/O parameter(the electrical energy, required per order of pollutant removal in $1m^3$ wastewater) were evaluated. TOC removal efficiencies of $UV/H_2O_2,\;UV/TiO_2/H_2O_2$, Photo-Fenton oxidation at the optimum conditions were 95.5%, 92.3%, 91.5%, respectively. The electrical energy requirements of $UV/H_2O_2,\;UV/TiO_2/H_2O_2$, Photo-Fenton oxidation were $11.26kWh/m^3,\;3.85kWh/m^3,\;0.799kWh/m^3$, respectively. From these results, it could be concluded that all of the three oxidation processes were effective for the degradation of citric acid. Considering the treatment efficiency and economical aspect, photo-Fenton oxidation was the most efficient treatment process among the three processes tested.

• The Korean Journal of Food And Nutrition
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• v.30 no.1
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• pp.96-104
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• 2017

To obtain the immunomodulating polysaccharide from chaga mushroom (Inonotus obliquus sclerotia, IO), crude polysac- charide fractions (IO-M-CP and IO-CP, respectively) prepared from hot-water extract (IO-W) of I. obliquus by EtOH precipitation after MeOH reflux or not. After IO-W was re-dissolved in water followed by EtOH addition in the case without MeOH reflux, EtOH mixture was fractionated into EtOH-soluble (IO-E) and crude polysaccharide (IO-CP). In the meanwhile, MeOH-soluble fraction (IO-M) was separated from IO-W after MeOH reflux. The residue was dissolved in water and was added by EtOH, and then EtOH mixture was also fractionation into EtOH-soluble (IO-M-E) and crude polysaccharide (IO-M-CP). As a result of the macrophage stimulating activity of these fractions, IO-CP and IO-M-CP showed significantly increased cell proliferation and cytokines production than IO-W. Particularly, IO-M-CP promotes the production of IL-12 more than IO-CP. In the splenocytes proliferating activity and intestinal immune system modulating activity through Peyer's patch, both of 2 crude polysaccharide fractions were significantly promoted in cell proliferation and cytokines production than IO-W, and IO-M-CP was more potent than IO-CP in IL-2 production from splenocytes and GM-CSF production ($10{\mu}g/mL$) in Peyer's patch cells. In addition, immunomodulating polysaccharide fractions (IO-M-CP and IO-CP) prepared from IO-W by EtOH precipitation with or without EtOH reflux showed no significant difference in the chemical composition and component sugar. These results suggested that MeOH reflux might exclude low-molecular weight materials from IO-W and consequently increase the immunomodulating activity of IO-M-CP. Therefore, it was confirmed that immunomodulation of polysaccharide prepared from hot-water extract of chaga mushroom was enhanced by fractionation including MeOH reflux and EtOH precipitation.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.32 no.2
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• pp.77-82
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• 2022

Recently, research on the development of low-cost/high-efficiency water electrolysis catalysts to replace noble metal catalysts is being actively conducted. Since overvoltage reduces the overall efficiency of the water splitting device, lowering the overvoltage of the oxygen evolution reaction (OER) is the most important task in order to generate hydrogen more efficiently. Currently, noble metal catalysts show excellent characteristics in OER performance, but they are experiencing great difficulties in commercialization due to their high price and efficiency limitations due to low reactivity. In this study, a water electrolysis catalyst Ni-MWCNT was prepared by successfully doping Ni into the MWCNTs structure through the pulsed laser ablation in liquid (PLAL) process. High resolution-transmission electron microscopy (HR-TEM) and X-ray photoelectron spectroscopy (XPS) were performed for the structure and chemical composition of the synthesized Ni-MWCNT. Catalytic oxygen evolution reaction evaluation was performed by linear sweep voltammetry (LSV) overvoltage characteristics, Tafel slope, electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV) and Chronoamperometry (CA) was used for measurement.

• International Journal of Highway Engineering
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• v.17 no.4
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• pp.53-61
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• 2015

PURPOSES : The objective of this study is to evaluate the SDAR (solvent deasphaltene residue), which is obtained from the solvent deasphalting (SDA) process, as a pavement material. METHODS : The physical properties of the SDAR were evaluated based on its chemical composition, and asphalt mixtures with the SDAR were fabricated and used for the evaluation of mechanical properties. Firstly, the chemical composition of SARA (saturate, aromatic, resin and asphaltene) was analyzed using the TLC-FID (thin-layer chromatography-flame ionization detector). Moreover, the basic material properties of the asphalt binder with the SDAR were evaluated by the penetration test, softening point test, ductility test, and PG (performance grade) grade test. The rheological properties of the asphalt binder with the SDAR were evaluated by the dynamic shear modulus ($G^*$) obtained using the time-temperature superposition (TTS) principle. Secondly, the mechanical properties of the asphalt mixtures with the SDAR were evaluated. The compactibility was evaluated using the gyratory compacter. Moreover, the tensile strength ratio (TSR) was used for evaluating the moisture susceptibility of the asphalt mixtures (i.e., susceptibility to pothole damage). The dynamic modulus $E^*$, which is a fundamental property of the asphalt mixture, obtained at different temperatures and loading cycles, was used to evaluate the mechanical properties of the asphalt mixtures. RESULTS AND CONCLUSION : The SDAR shows stiffer and more brittle behavior than the conventional asphalt binder. As the application of the SDAR directly in the field may cause early failures, such as cracks on pavements, it should be applied with modifiers that can favorably modify the brittleness property of the SDAR. Therefore, if appropriate additives are applied on the SDAR, it can be used as a pavement material because of its low cost and strong resistance to rutting.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.58-58
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• 2009

Uniformity related issues in chemical mechanical polishing (CMP) are within wafer non-uniformity (WIWNU), wafer to wafer non-uniformity (WTWNU), planarity and dishing/erosion. Here, the WIWNU that originates from spatial distribution of independent variables such as temperature, sliding distance, down force and material removal rate (MRR) during CMP, relies to spatial dependency. Among various sources of spatial irregularity, hardness and modulus of pad and surface roughness in sources for pad uniformity are great, especially. So, we investigated the spatial variation of pad surface characteristics using pad measuring system (PMS) and roughness measuring system. Reduced peak height ($R_{pk}$) of roughness parameter shows a strong correlation with the removal rate, and the distribution of relative sliding distance onwafer during polishing has an effect on the variation of $R_{pk}$ and WIWNU. Also, the results of pad wear profile thorough developed pad profiler well coincides with the kinematical simulation of conditioning, and it can contribute for the enhancement of WIWNU in CMP process.

• Proceedings of the Korea Water Resources Association Conference
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• 2005.05b
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• pp.393-398
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• 2005

Suspended fine mineral particles are deposited at the areas with low flow velocity and low transportation capacity in rivers, reservoirs and lakes. It can be contaminated by heavy metals. Examples of problem fields art dredging of sediment, water pollutants, and maintenance of navigation channels and construction works. To deal with the settling problems it is necessary to understand tile physico-chemical characteristics of cohesive sediment under varying density of particle and ion addition(NaOH, HCl, NaCl), which is dissolved in river, because fine-grained cohesive sediment can lead to flocculation with the physico-chemical influences and takes different characteristics. Experiments with fresh and saline water are followed with fine-grained sediments(alumina and quartz) in settling columns. Settling velocity of suspended fine particles in still water was measured with a pressure sensor(maximum 10 mbar). Until the initial concentration of 20,000 mg/1 of alumina and quartz the settling velocity was on the increase. Above this initial concentration was it on the decrease. In an acid condition, which causes strong flocculation, average settling velocity of quartz powder was high. In an alkaline water low average settling velocity of it was observed. However, alumina behaved exactly contrarily.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.9 no.2
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• pp.16-22
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• 2006

This study was carried out to estimate the physical and chemical soil characteristics in highway cutting slope areas. The soil was sampled in cutting area and natural vegetation area that was located in the upper areas of the highway cutting slope. The average total soil depth, bulk density, and soil hardness were bad in the highway cutting slope sites. The sandy loam was the most soil texture in the study area. The concentration of soil organic matter and nitrogen were very low in all highway cutting areas. The concentration of exchangeable cations was similar between the highway cutting slope and the natural vegetation sites in each highway. The soil pH was higher in highway cutting slope areas than in natural vegetation sites. In conclusion, chemical and physical properties of soil were bad in the cutting slope than in the natural vegetation area because of the loss of soil by cutting of slope area and less organic matter input by less vegetation in the highway cutting slope area. We should employ possible method to reduce the loss of soil, and compost and fertilization treatment could help to increase soil nutrient content in the cutting slope area.

• Asian Journal of Atmospheric Environment
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• v.9 no.1
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• pp.78-85
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• 2015

In the past several decades, biofuels have emerged as candidates to help mitigate the issues of global warming, fossil fuel depletion and, in some cases, atmospheric pollution. To date, the only biofuels that have achieved any significant penetration in the global transportation sector are ethanol and biodiesel. The global consumption of biodiesel was rapidly increased from 2005. The goal of this study was to examine the chemical composition on particulate pollutant emissions from a diesel engine operating on several different biodiesels. Tests were performed on non-road diesel engine. Experiments were performed on 5 different fuel blends at 2 different engine loading conditions (50% and 75%). 5 different fuel blends were ultra-low sulfur diesel (ULSD, 100%), soy biodiesel (Blend 20% and Blend 100%) and canola biodiesel (Blend 20% and Blend 100%). The chemical properties of particulate pollutants were characterized using an Aerodyne High Resolution Time of Flight Aerosol Mass Spectrometer (HR-ToF-AMS). Organic matter and nitrate were generally the most abundant aerosol components and exhibited maximum concentration of $1207{\mu}g/m^3$ and $30{\mu}g/m^3$, respectively. On average, the oxidized fragment families ($C_xH_yO_1{^+}$, and $C_xH_yO_z{^+}$) account for ~13% of the three family sum, while ~87% comes from the $C_xH_y{^+}$ family. The two peaks of $C_2H_3O_2$ (m/z 59.01) and $C_3H_7O$ (m/z 59.04) located at approximately m/z 59 could be used to identify atmospheric particulate matter directly to biodiesel exhaust, as distinguished from that created by petroleum diesel in the AMS data.