• Applied Chemistry for Engineering
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• v.16 no.4
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• pp.527-532
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• 2005

Ionic polymer metal composites (IPMC) are soft polymeric smart materials having large displacement at low voltage in air and water. The polymeric electrolyte actuator consists of a thin and porous membrane and metal electrodes plated on both faces, in impregnation electro-plating method. The response and actuation of actuator are governed. Among many factors governing the activation and response of IPMC actuator, the surface electrode plays an important role. In this study, the well-designed modification of electrode surface was carried out in order to improve the chemical stability well as electromechanical characteristics of the IPMC actuator. We employed Ion Beam Assisted Deposition (IBAD) method to prepare the topologically homogeneous thin surface electrode. After roughing the surface of Nafion membrane in order to get a larger surface area, the IPMC was prepared by impregnation for electro-plating and re- coating on the surface through traditional chemical deposition, followed by an additional surface treatment with high conductive metals with IBAD. It was observed that our IPMC specimen shows the enhanced surface electrical properties as well as the improved actuation and response characteristics under applied electric field.

• Journal of Life Science
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• v.22 no.11
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• pp.1463-1469
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• 2012

To add functional specialty in a traditional fermentation product, Gochujang, and improve the taste and preference, an optimum fermentation condition of Gochujang supplemented with tomato puree was established in the conditions of GCJ 14, -16, -18, and -20. Varying the salinity concentration and the manufactured fermentation products, Gochujang was analyzed by the chemical nature, change in bacterial characteristics and contents of a functional chemical, lycopene, and sensory taste. As a result, the pH change of Gochujang containing tomato puree with grain syrup was diminished during the fermentation process. Its sugar contents were repeated by the increase and decrease. In addition, the water contents, salinity, and chromaticity of the Gochujang showed no significant change. Regarding the change in bacterial characteristics, total bacterial number and lactic acid bacteria number increased, with the rate of increase depending on the fermentation process. The ratio of lactic acid bacteria number against total bacterial number was confirmed to be significantly high at the conditions of GCJ 18 and -20. No significant change in the contents of lycopene was observed during the fermentation process. Notably, the change in crude proteins, crude fat, crude ash, and carbohydrates in addition to a sensory examination including taste and preference of the manufactured Gochujang suggest that the optimal fermentation product is produced in the condition of GCJ 20. Therefore, functional Gochujang satisfying a modern preference can be produced by using tomato puree with grain syrup.

• Journal of Life Science
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• v.19 no.11
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• pp.1553-1561
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• 2009

This study investigated the biological activities and chemical characteristics of Monascus-fermented Korean red ginseng (MFRG). The comparative activities of water, ethanol, and methanol extracts from MFRGE and Korean red ginseng (RG) were tested in vitro of anti-oxidative models of linoleic acid peroxidation by thiocyanate and thiobarbituric acid (TBA) methods and DPPH ($\alpha,\alpha'$-diphenyl-$\beta$-picrylhydrazyl)radical scavenging activities. In addition, measurements of their bioactive total phenolic compounds and minerals, and extract yield, were obtained. The extract yield of each solvent extracted from MFRG and RG was aqueous by 6.58% and 5.83%, ethanol by 0.62% and 0.98%, and methanol by 1.27% and 3.04%, respectively. Total phenolic compounds were higher in all solvents extracted from MFRG than those from RG. Major mineral contents (ppm) of MFRG and RG were K by 16,936 and 22,386, Ca by 2,310 and 3,693, Mg by 2,703 and 2,647, respectively. The DPPH radical scavenging activities were higher in all solvents extracted from MFRG than those from RG, however, all these extracts exhibited a relatively low level of radical-scavenging activity compared to the butylated hydroxytoluene (BHT). In antioxidative activities determined by TBA method using linoleic acid peroxidation, 70% methanol extract from MFRG and RG showed the highest antioxidative activity at a concentration of 0.1%. These results may provide the basic data to understand the biological activities of bio-active materials derived from MFRG.

• Food Science of Animal Resources
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• v.24 no.3
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• pp.246-252
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• 2004

The objective of this study was to determine the changes of physico-chemical characteristics in crossbred pigs (Korean native breed ${\times}$ Landrace breed) by carcass grade. Research was conducted on 250 pigs divided into 5 carcass grade groups. Cooking loss have significantly (p<0.05) higher in higher carcass grade. However, water content, crude fat, pH and shear force have no difference. In meat color, a＊ was significantly (p<0.05) higher in C and D grade, whereas A grade was lower than those of others. L＊ and b＊ did not different among the carcass grades. In fat color, A and E grade were significantly (p<0.05) higher in b＊ and, C was lower than those of others. Adhesiveness and Gumminess of cooked meat were significantly (p<0.05) higher when carcass grade was higher. However hardness, cohesiveness, springiness and brittleness were not different among the carcass grades. Palmitic acid was significantly (p<0.05) higher in higher carcass grades and, saturated fatty acid/unsaturated fatty acid ratio was lower, whereas other fatty acids compositions had no difference among the carcass grades.

• Applied Biological Chemistry
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• v.29 no.1
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• pp.90-95
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• 1986

A comparative study of chemical characteristics, efficacy and relative merits of extruded and coated granules, containing fungicide and insecticide, was conducted under laboratory and field conditions. Probenzole (3-allyloxy-1,2-benzisothiazole 1,1-dioxide) and carbofuran (2,3-dihydro-2,2-dimethyl-7-benzofuranyl methyl carbamate) were chosen as toxicants for rice blast(Pyricularia oryzae) and brown planthopper (Nilaparvata lugens) control, respectively. Stability of active ingredients in coated granule was superior to the extruded one under accelerated temperature. Active ingredient dissolution of coated one into distilled water showed slow release pattern. Pesticide residues in rice (Oryzae sativa, Chucheongbyeo) shoot applied with extruded one at the dosage of 3kg/10a retained higher levels than those with coated one on two days after application, while the residue levels were a reversed tendency on eight days after application. Efficacy on rice blast exhibited minute differences between the granules, on the other hand efficacy on brown planthopper by coated one was of higher rank than that by extruded one. Production cost of the combined pesticide granule by coating method could be cut down by 6% as compared to extrusion method.

• Journal of the Korean Society of Marine Environment & Safety
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• v.17 no.3
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• pp.203-218
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• 2011

Long-term trends and distribution patterns of water quality were investigated in the Yeoja Bay of South Sea, Korea from 1976 to 2010. Water samples were collected at 3 stations and physicochemical parameters were analyzed including water temperature, salinity, hydrogen ion concentration (pH), dissolved oxygen (DO), chemical oxygen demand (COD), suspended solids (SS) and nutrients. Spatial distribution patterns of temperature, pH and DO were not clear among stations but the seasonal variations were distinct except ammonium. The trend analysis by principal component analysis (PCA) during 31 years revealed the significant variations in water quality in the study area. Spatial water qualities were discriminated into 2 clusters by PCA; station cluster 1 and 2~3. Annual water qualities were clearly discriminated into 4 clusters by PCA. By this multi-variate analysis, the annual trends were summarized as the followings; water temperature, COD and SS tended to increase from late 1970's, decreased salinity, and increased phosphate from 1991 to 2001 and increased dissolved inorganic nitrogen. Water quality was showed by the input of fresh water same as those of Kyoungin coastal area, Asan coastal area, Choensoo bay, Gunsan coastal and Mokpo coastal area in the Yeoja Bay.

• Journal of Soil and Groundwater Environment
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• v.13 no.1
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• pp.1-12
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• 2008

The purpose of this study is to characterize the hydrogeochemical characteristics of hot spring waters and to interpret the source of noble gases and the geochemical environment of the hot spring waters distributed along the eastern area of the Korean peninsula. For this purpose, We carried out the chemical, stable isotopic and noble gas isotopic analyses for eleven hot spring water and fourteen hot spring gas samples collected from six hot spring sites. The hot spring waters except the Osaek hot spring water show the pH range of 7.0 to 9.1. However, the Osaek $CO_2$-rich hot spring water shows a weak acid of pH 5.7. The temperature of hot spring waters in the study area ranges from $25.7^{\circ}C$ to $68.3^{\circ}C$. Electrical conductivity of hot spring waters varies widely from 202 to $7,130{\mu}S/cm$. High electrical conductivity (av., $3,890{\mu}S/sm$) by high Na and Cl contents of the Haeundae and the Dongrae hot spring waters indicates that the hot spring waters were mixed with seawater in the subsurface thermal system. The type of hot springs in the viewpoint of dissolved components can be grouped into three types: (1) alkaline Na-$HCO_3$ type including sulfur gas of the Osaek, Baekam, Dukgu and Chuksan hot springs, and (2) saline Na-Cl type of the Haeundae and Dongrae hot springs, and (3) weak acid $CO_2$-rich Na-$HCO_3$ type of Osaek hot spring. Tritium ratios of the Haeundae and the Dongrae hot springs indicate different residence time in their aquifers of older water of $0.0{\sim}0.3$ TU and younger water of $5.9{\sim}8.8$ TU. The ${\delta}^{18}O$ and ${\delta}D$ values of hot spring waters indicate that they originate from the meteoric water, and that the values also reflect a latitude effect according to their locations. $^3He/^4He$ ratios of the hot spring waters except Osaek $CO_2$-rich hot spring water range from $0.1{\times}10^{-6}$ to $1.1{\times}10^{-6}$ which are plotted above the mixing line between air and crustal components. It means that the He gas in hot spring waters was originated mainly from atmosphere and crust sources, and partly from mantle sources. The Osaek $CO_2$-rich hot spring water shows $3.3{\times}10^{-6}$ in $^3He/^4He$ ratio that is 2.4 times higher than those of atmosphere. It provides clearly a helium source from the deep mantle. $^{40}Ar/^{36}Ar$ ratios of hot spring water are in the range of an atmosphere source.

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.10 no.6
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• pp.62-72
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• 1996

In this paper, ozonizer using U-type lamp(Olamp) has been designed and manufactured, which can perform a role of lighting source and ozonizer by using photo and chemical methods. The discharge, spectrum, illuminance, ozone concentration, ozone generation, ozone yield and sterilization characteristics of Olamp have been studied. The important conclusions obtained from this paper can be summa'||'&'||'not;rized as follows. As a result of spectrum characteristics for Olamp, ultraviolet ray of a short wave'||'&'||'not;lengths and a visible ray are radiated. The illuminance of Olamp was found to be useful for "color distinctive and intermittent works in the dark working spaces" in accordance with KS A 3011. The ozone concentration of gaseous phase is inversely proportional to quality of supplied gas. Also, ozone conce tration and generation of gaseous phase are rised more commercial oxygen gas than those trial air gas for constant quality of supplied gas. Ozone generation and ozone yield of gaseous phase are proportion'||'&'||'not;al to ozone concentration of gaseous phase. The characteristics of liquid ozone concentration at distilled water are proportional to circulating velocity of fermentation chamber and ozone concentration of gas'||'&'||'not;eous phase. As a result, the sterilization characteristics of Escherichia coli have been obtained more than 97[ % J.

• Korean journal of food and cookery science
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• v.28 no.6
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• pp.789-796
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• 2012

This study attempted to investigate the characteristics of Superjami, which had a high C3G (cyandin-3-glucoside) content by comparing it with common rice (Ilpum) and black rice (Heougjinju, Suwon 415) for their components and physio-chemical characteristics. There were no significant differences in the water content, however there were significant differences in crude protein and crude fat in the order of Ilpum < Superjami < Heougjinju. As for the morphological characteristics of grains, it had been learned that Superjami was heavier and longer than the common rice, moreover Superjami had bigger seeds. As for the hardness of grains, the longer the time of steeping, the more decreased their hardness was at large. In the case of color, they showed significant differences in all the L, a, and b values of grains and flours. As a result of the experiment of pigment elution after steeping of the rice flours at $20^{\circ}C$ and $40^{\circ}C$, the longer the time steeping, the more increased the pigment elution became. The values are bigger with Heougjinju and Superjami than with Ilpum. As for the elution pH after rice steeping, the longer the time of steeping, the lower pH all the assays tended to have. As a result of the analysis of the total polyphenol contents of Ilpum, Heougjinju, and Superjami, it had turned out that the total polyphenol contents of Heougjinju and Superjami are 1.2 times as high as Ilpum, a common rice, and that Superjami is significantly higher than Heougjinju. As a result of the experiment of DPPH radical scavenging ability, there are significant differences among the assays in the order of Superjami > Heougjinju > Ilpum. Futher, it has turned out that Superjami has a higher DPPH radical scavenging ability than Heougjinju. Consequently, it can be stated that Superjami has a strong anti-oxidative ability. Thus, we should more precisely grasp the cooking characteristics of Superjami, which is in the state of brown rice, via comparing it with a common brown rice, and also provide opportunities to apply Superjamii to more foods by studying its starch characteristics in addition to its grain and flour properties.

• Applied Chemistry for Engineering
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• v.27 no.6
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• pp.646-652
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• 2016

Biomass is regarded as one of the promising energy sources to deal with the depletion of fossil fuels and the global warming issue. Biocrude-oil can be produced through the fast pyrolysis of biomass feedstocks such as wood, crops, agricultural and forestry residues. It has significantly higher viscosity than that of conventional petroleum fuel and contains solid residues, which can lower the spray and atomization characteristics when applied to the burner. In addition, biocrude-oil consists of hundreds of chemical species derived from cellulose, hemicellulose and lignin, and evaporation characteristics of the biocrude-oil droplet are distinct from the conventional fuels. In the present study, a numerical study was performed to investigate the evaporation characteristics of biocrude-oil droplet using a simplified composition of the model biocrude-oil which consists of acetic acid, levoglucosan, phenol, and water. The evaporation characteristics of droplets were compared at various surrounding air temperatures, initial droplet diameters, and ethanol mixing ratios. The evaporation time becomes shorter with increasing air temperature, and it is much sensitive to the air temperature particularly in low temperature ranges. It was also found that the biocrude-oil droplet evaporates faster in cases of the smaller initial droplet diameter and larger ethanol mixing ratio.