• Proceedings of the KSME Conference
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• 2001.06d
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• pp.802-806
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• 2001

Diesel particulate trap is the most reliable system to reduce the particulate matters from diesel engine. Filter is the core component of DPF and ceramic monolith type is dominantly used, which is expensive and fragile relatively at thermal shock. Porous metal filter, which has superior thermal characteristics and low cost, was tested in order to analyze the regeneration performance by using with ferrocene additive. This filter showed the 72% filtration efficiency, additives itself diminished 48% of PM from engine out emission, and final PM reduction ratio of 89% was achieved by DPF system with D-13 test mode.

• Journal of the East Asian Society of Dietary Life
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• v.11 no.4
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• pp.295-304
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• 2001

This study was conducted to investigate the cooking properties of noodles made from composite flour blended with green tea powder. As the ratio of green tea powder increased, development time was longer than that of the control. The stability of dough showed higher value than the control except 2% addition group. The highest viscosity was at the 4% addition group. but 2% addition group showed the lowest viscosity. As the additional ratio of green tea powder was increased. the volume expansion ratio was increased, but water soluble solid matters contents in all addition groups had a lower level than that of the control. Also, the yellowness level of noodle was increased, but the brightness, redness and color and flavor acceptability was decreased, as the additional ratio was increased. However. 2~4% addition group of green tea powder had a similar acceptability profile to that of the control group.

• Journal of Mechanical Science and Technology
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• v.19 no.3
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• pp.870-876
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• 2005

It seems very difficult to comply with upcoming stringent emission standards in vehicles. To develop low emission engines, better quality of automotive fuels must be achieved. Since sulfur contents in diesel fuels are transformed to sulfate-laden particulate matters as a catalyst is applied, it is necessary to provide low sulfur fuels before any Pt-based oxidation catalysts are applied. In general, flash point, distillation $90\%$ and cetane index are improved but viscosity can be worse in the process of desulfurization of diesel fuel. Excessive reduction of sulfur may cause to degrade viscosity of fuels and engine performance in fuel injection systems. This research focused on the performance of an 11,000 cc diesel engine and emission characteristics by the introduction of ULSD, bio-diesel and a diesel oxidation catalyst, where the bio-diesel was used to improve viscosity of fuels in fuel injection systems as fuel additives or alternative fuels.

• Journal of the Korean Chemical Society
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• v.19 no.4
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• pp.252-257
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• 1975

This experimental study was carried out to examine the utilization of the anthracite ash as a fertizer. It was found that the ash had very small amount of the soluble matters in 2% citric acid solution therefore it is proved ineffective as a fertilizer. When the small amount of calcinated dolomite was added to the anthracite, it was observed that the resulting ash showed much increased solubility of magnesium, calcium, sulfur and silica etc in the citric acid solution. So it is concluded that the ash of the mixture of anthracite and calcinated dolomite would be one of the useful soil-conditioner and supplyer of nutrients.

• Proceedings of the Membrane Society of Korea Conference
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• 1997.04a
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• pp.111-130
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• 1997

The lack of water resources is becoming worse due to water pollution with accelerated industrialzation and regional unbalanced distribution of water resources. In recent, the production water quality is decreasing because of the increased organic matters and soluble solids in the water sources for power plants. The purpose of this paper discribes the ststus and prospect of membrane application in electric power industry. So this study lies in developing a process which can produce high purity water by appluing RO(Reserve Osmosis) ahead of the IX(Ion Exchange) tower and evaluating the product water quality and the cost effectiveness. The capital and operating cost for the treatment of brackish water, sea water by RO were presented as a reference for the review on securing water source for the new plant site.

• Journal of Environmental Health Sciences
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• v.39 no.1
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• pp.56-70
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• 2013

Objectives: This paper aims to investigate the seasonal deposition characteristics of water-soluble ion species by comparing the deposition amount of two samples taken according to different sampling methods of deposition for ambient aerosol such as gases and particulate matters. Methods: Deposition samples were collected using two deposition gauges in the downtown area of Iksan City over approximately two weeks of each season in 2004. The type of deposition gauges consisted of two different sampling methods known as dry gauge and a wet gauge. The dry gauge was empty and used a dry PE bottle with an inlet diameter of 9.6 cm. Before the beginning of each deposition sampling, a volume of 30-50 ml distilled ionized water was added to the wet gauge to wet the bottom during the sampling period. Deposition samples were measured twice per day and analyzed for inorganic water-soluble ion species using ion chromatography. Results: The daily deposition amounts of all measured ions in the dry gauge and the wet gauge showed a significant increase when precipitation occurred, having no difference of deposition amount between in the wet gauge and in the dry gauge. By excluding two samples from rainy days during the sampling period, the mean daily deposition of all ions in dry gauge and wet gauge were $6.58mg/m^2/day$ and $18.16mg/m^2/day$, respectively. The mean deposition amounts of each ion species were higher in the wet gauge than in the dry gauge because of the surface difference of the sampling gauge, especially for $NH_4{^+}$ and ${SO_4}^{2-}$. The mean deposition amounts of $NH_4{^+}$ and ${SO_4}^{2-}$ in the wet gauge were found to be about 15.4 times and 5.2 times higher than that in dry gauge, with a pronounced difference between spring and summer, while the remaining ion species were 1.1-2.0 times higher in the wet gauge than in the dry gauge. Dominant species in the dry gauge were $Ca^{2+}$ and $NO_3{^-}$, accounting for 36.4% and 18.1% of the total ion deposition, whereas those in the wet gauge were $NH_4{^+}$ and ${SO_4}^{2-}$, accounting for 32.5% and 25.0% of the total ion deposition, respectively. Conclusion: The seasonal differences in deposition amounts of water-soluble ion species in ambient aerosol depending on the two types of different sampling methods were identified. This suggests that the removal of ambient aerosol is strongly influenced by the weather conditions of each season as well as the condition of earth's surface, such as dry ground and water.

• Korean Journal of Environmental Agriculture
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• v.35 no.2
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• pp.121-127
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• 2016

BACKGROUND: Anaerobic digestion is the most feasible technology because not only the energy embedded in organic matters can be recovered, but also they are stabilized while being degraded. This study carried out to improve methane yield of slaughterhouse wastewater treatment sludge cake by the thermal pre-treatment prior to anaerobic digestion.METHODS AND RESULTS: Slaughterhouse wastewater treatment sludge cake was pre-treated by the closed hydrothermal reactor at reaction temperature of 190℃. BMPs (Biochemical methane potential) of the thermal hydrolysate was tested in the different S(Substrate)/I(Inoculum) ratio conditions. COD(Chemical oxygen demand) and SCOD(Soluble chemical oxygen demand) contents of thermal hydrolysate were 10.99% and 10.55%, respectively, then, the 96.00% of COD was remained as a soluble form. The theoretical methane potential of thermal hydrolysate was 0.51 Nm³ kg^-1-VS_added. And BMPs were decreased from 0.56 to 0.22 Nm³ kg^-1-VS_added when S/I ratio were increased from 0.1 to 2.0 in the VS content basis. Those were decreased from 0.32 to 0.13 Nm³ kg^-1-COD_added when S/I ratio were increased from 0.1 to 2.0 based on COD content. The anaerobic degradability of VS basis have showed 196.9%, 102.2%, 80.7%, 67.4%, and 39.4% in S/I ratios of 0.1, 0.3, 0.5, 1.0, and 2.0, respectively. Also the COD of 119.6%, 76.3%, 70.1%, 69.0%, and 43.1% were degraded anaerobically in S/I ratios of 0.1, 0.3, 0.5, 1.0, and 2.0, respectively.CONCLUSION: BMPs obtained in the S/I ratios of 0.1 and 0.3 was overestimated by the residual organic matters remaining at the inoculum. And inhibitory effect was observed in the highest S/I ratio of 2.0. The optimum S/I ratios giving reasonable BMPs might be in the range of 0.5 and 1.0 in S/I ratio. Therefore VS biodegradability of thermal hydrolysate was in 67.4-80.7% and COD biodegradability showed 69.0-70.1%.

• Korean Journal of Food Science and Technology
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• v.24 no.4
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• pp.306-310
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• 1992

The effects of membrane type, temperature and pH on the permeate flux and removal of soluble solids from soybean curd whey by reverse osmosis were studied at recommended pressures for optimum performance of the membranes. The fluxes obtained with HR 95 and HR 98 membranes at 60 bar were not lower than that with CA 930 membrane at 20 bar. Soluble solid content in the permeate increased to 1.5 Brix after 90 min by CA 930 membrane, as opposed to 0 Brix with the HR 95 and HR 98 membranes. Permeate flux was increased by 28.4% as operation temperature increased from $30^{\circ}C$ to $50^{\circ}C$. COD of the whey was rejected up to 80.5%, 99.7% and 99.5% by using the membranes of CA 930, HR 95 and HR 98, respectively. pH adjustment of the whey resulted in decreasing membrane performance. But the rejection rate of COD in permeate with HR 98 membrane was slightly increased to 99.9% when the pH was adjusted to 7.0.

• Journal of Environmental Health Sciences
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• v.33 no.5
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• pp.408-421
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• 2007

The concentration characteristics of atmospheric particle matters (PM) including $PM_{2.5},\;PM_{10}$, and TSP were evaluated through the measurement data of PM_{2.5}$ (fine particulate), PM_{10-2.5}$ (coarse particulate), and PM_{over-10}$ collected using a MCI (multi-nozzle cascade impactor) sampler of a three-stage filter pack in spring of 2006 in Iksan area. During the sampling period of 10-15 March and 24 days from 8 April to 2 May, 32 samples for PM of each size fractions were collected, and then measured for PM mass concentrations and water-soluble inorganic ion species. Average concentrations of $PM_{2.5},\;PM_{10}$, TSP were $57.9{\pm}44.1mg/m^3$, $96.6{\pm}89.1mg/m^3$, and $114.8{\pm}99.7mg/m^3$, respectively. Water-soluble inorganic ion fractions to PM mass were found to be 36.5%, 18.0%, and 11.1% for $PM_{2.5}$, $PM_{10-2.5}$ and $PM_{over-10}$, respectively. By showing the high concentrations of PM samples during Asian dust events, those three fractions of PM were distinguished between the samples of Asian dust event and the samples of no event. However, the increase of PM concentrations observed during Asian dust events showed a different pattern for some Asian dust events. The differences of those three fractions in the size distribution may depend on differences on place of occurrence of Asian dust storm and course of transport from China continent to Iksan area in Korea. However, the extent of PM mass contribution during Asian dust events was generally dominated by the coarse particles rather than the fine fraction of PM. The variations of water-soluble inorganic ion species concentration in those three PM fractions between the samples of Asian dust event and the samples of no event were also discussed in this study.

• Journal of Korean Society for Atmospheric Environment
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• v.31 no.1
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• pp.15-27
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• 2015

The collection of fine particulate matter samples was made at Gosan site of Jeju Island, one of the background sites of Korea, during a year of 2013, and their water-soluble ionic species were analyzed in order to examine the chemical compositions and pollution characteristics. The concentrations of $nss-SO_4{^{2-}}$, $NH_4{^{+}}$, $NO_3{^{-}}$, and $K^+$ had occupied 66.0% of water-soluble ionic species in $PM_{10}$, especially 94.3% in $PM_{2.5}$ fine mode, however the $nss-Ca^{2+}$ and $Na^+$ showed high concentrations in $PM_{10-2.5}$ coarse mode. $NO_3{^-}/nss-SO_4{^{2-}}$ concentration ratios in $PM_{10}$ and $PM_{10-2.5}$ were 0.30 and 0.13, showing less significant effect from automobile and local pollution sources. The sulfate and nitrate compounds were presumed to be long-range transported to Gosan area by the relatively high SOR and NOR values. The trajectory cluster analysis showed the higher concentrations of the major secondary pollutants ($nss-SO_4{^{2-}}$, $NO_3{^{-}}$, $NH_4{^{+}}$) and $nss-Ca^{2+}$ when the air masses had moved from China continent and Korean peninsula into Gosan area.