• Journal of the Korean Applied Science and Technology
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• v.28 no.1
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• pp.35-47
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• 2011

For the synthesis of water soluble acrylic modified epoxyester resin, fatty acid/epoxy ratio of 50/50 was used, and introduced maleic anhydride. Ratio of styrene/acrylic acid of acrylic monomers was fixed 85/15 and ratio of epoxyester/acrylic monomer was controlled 80/20, 75/25, 70/30, 65/35, and degree of neutralization were changed 65%, 80%, to 100%. As a result, 40% solids acrylic modified epoxyester resins were synthesized. Resins were evaluated water soluble stability, drying time, water resistant, storage stability and physical properties. And the white paints were prepared, and were evaluated viscosity, drying time, water resistance, adhesion, sagging, spray workability, gloss, salt spray resistance, skinning, whiteness and flash rust. As a result, the degree of neutralization of 100% and the ratio of epoxyester/acrylic monomer of 75/25 showed the best properties.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.7 no.3
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• pp.453-457
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• 2006

A long-term leaching column experiment was performed to evaluate the teachability of the stabilized lead-contaminated soil using soluble phosphate. The study shows that Pb in the leachate was little detected and the remaining $PO_4-P$ concentration kept below 0.1 mg/L due to the formation of geochemically stable lead phosphate minerals from the reactions of labile soil Pb forms with the added soluble phosphate salt. After the experiment, there was no Pb migration from the top to the bottom of the stabilized soil column. But the Pb concentrations of the 12 soil samples from the control column decreased with the increase of the soil depth.

• Nuclear Engineering and Technology
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• v.43 no.3
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• pp.195-204
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• 2011

The effects on pool boiling heat transfer of aqueous solutions of boric acid ($H_3BO_3$) and sodium chloride (NaCl) as working fluids have been studied. Borated and NaCl water were prepared by dissolving 0.5~5% volume concentration of boric acid and NaCl in distilled-deionized water. The pool boiling tests were conducted using $1{\times}1\;cm^2$ flat heaters at 1 atm. The critical heat flux (CHF) dramatically increased compared to boiling pure water. At the end of boiling tests it was observed that particles of boric acid and NaCl had deposited and formed a coating on the heater surface. The CHF enhancement and surface modification during boiling tests were very similar to those obtained from boiling with nanofluids. Additional experiments were carried out to investigate the reliability of the additives deposition in pure water. The boric acid and NaCl coatings disappeared after repeated boiling tests on the same surface due to the soluble nature of the coatings, thus CHF enhancement no longer existed. These results demonstrate that not only insoluble nanoparticles but also soluble salts can be deposited during boiling process and the deposited layer is solely responsible for significant CHF enhancement.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.1
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• pp.133-140
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• 1995

This investigation was undertaken for the purpose of studying the changes of pectic substances in alcohol insoluble solids(AIS) extracted from cucumbers pickled in salt. The preparation methods were brining the cucumbers in 10% NaCl solution (bolied, method A), 20% NaCl solution(bolied, method B) and 20% NaCl solution(cool to $25^{\circ}C$ after boiling, method C). The composition ratio of hot water soluble pectin(HWSP) in AIS decreased during brining, while that of 0.4% sodium hexametaphosphate soluble pectin(NaSP) increased remarkably. The contents of Ca and Mg in AIS increased regardless of preparation methods used. By DEAE-cellulose chromatography, HWSP from fresh and brined cucumbers were divided into six fracitons. 0.2M peak was the main fraction in fresh cucumber, whereas 0.05M and 0.2M peak were the main fraction in pickled cucumbers. On the other hands, NaSP from fresh and brined cucumbers were divided into five fractions and 0.4M peak was the main fraction. However, the composition ratios of galacturonic acid and neutral sugar of 0.4M fraction in brined cucumbers were higher than those of fresh cucumber.

• Korean Journal of Human Ecology
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• v.13 no.1
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• pp.91-96
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• 2004

Effects of irradiation on physical and chemical properties of chicken were investigated. Chicken was irradiated at dose levels of 0, 0.5, 1, 3 and 5 kGy using Co60 source. Irradiation increased drip loss and TBA value. Irradiation decreased L value, and increased a value and b value, indicating that irradiation made chicken darker, more reddish and more yellowish. Irradiation induced the degradation in salt-soluble protein, not water-soluble protein. Any differences in color, odor and tenderness between irradiated and non-irradiated chicken were not perceived by sensory panels.

• Journal of the Korean Society of Food Culture
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• v.6 no.1
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• pp.61-69
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• 1991

Brewing method and quality of 10 sample of traditional Dungge-Jang in Kyungsang-Do area were investigated. In order to improve the taste of Dungge-Jang, some amount of boiled bean was added in the Dungge-Jang at early stage of fermentation. The level of amino nitrogen turned out to be low while that of water soluble protein and salt soluble protein was high. Glutamic acid, aspartic acid and proline were the major amino acid in water and salt soluble protein in traditional Dungge-Jang in Kyungsang-Do area. The content of total sugar and free reducing sugar were found to be considerably high, and among the free sugar, glucose was the highest$(2.16{\sim}4.02\;mg/ml)$, followed by maltose and maltotriose. Activities of acid protease and liquefying amylase were $0.13{\sim}1.36$ unit per milliliter and $10.18{\sim}15.19D^{40o}_{30}$ respectively. Result of sensory evaluation showed that the good Dungge-Jang turned out to have well harmonized taste of flavor, sweetness and sourness while the color looked slightly dark and yellow.

• Journal of Environmental Science International
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• v.28 no.1
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• pp.107-123
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• 2019

The aerosol chemical components in $PM_{2.5}$ in several regions (Seoul, Busan, Daejeon, and Jeju Island) were investigated with regard to their concentration characteristics and optical properties. The optical properties of the various aerosol components (e.g., water-soluble, insoluble, Black Carbon (BC), and sea-salt) were estimated using hourly and daily aerosol sampling data from the study area via a modeling approach. Overall, the water-soluble component was predominant over all other components in terms of concentration and impact on optical properties (except for the absorption coefficient of BC). The annual mean concentration and Aerosol Optical Ddepth (AOD) of the water-soluble component were highest in Seoul (at the Gwangjin site) ($26{\mu}g/m^3$ and 0.29 in 2013, respectively). Further, despite relatively moderate BC concentrations, the annual mean absorption coefficient of BC ($21.7Mm^{-1}$) was highest in Busan (at the Yeonsan site) in 2013, due to the strong light absorbing ability of BC. In addition, high AODs for the water-soluble component were observed most frequently in spring and/or winter at most of the study sites, while low values were noted in summer and/or early fall. The diurnal variation in the AOD of each component in Seoul (at the Gwangjin site) was slightly high in the morning and low in the afternoon during the study period; however, such distinctions were not apparent in Jeju Island (at the Aweol site), except for a slightly high AOD of the water-soluble component in the morning (08:00 LST). The monthly and diurnal differences in the AOD values for each component could be attributed to the differences in their mass concentrations and Relative Humidities (RH). In a sensitivity test, the AODs estimated under RH conditions of 80 and 90% were factors of 1.2 and 1.7 higher, respectively, than the values estimated using the observed RH.

• Korean Journal of Food Science and Technology
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• v.20 no.3
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• pp.447-452
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• 1988

In order to study effect of freezing rates on the quality changes such as pH, TBA value, free fatty acids and protein extractability, cylindrical chopped beef logs with 10cm of diameter and 10cm of height were frozen at three freezing rates(0.97cm/hr, 2.05cm/hr, 3.71cm/hr)using air blast freezer. Physicochemical changes of frozen meat were investigated during forzen storage at $-20^{\circ}C$ for 16weeks. Results on pH change showed $0.1{\sim}0.2unit$ increase at the 16th week of the frozen storage and the change was smaller with the increasing freezing rates. Free fatty acids content and TBA value also were increased during forzen storage, but they were minimal at 3.71cm/hr freezing rate. Correlation coefficient between TBA value and free fatty acids content were highly significant(r=0.804). After 16weeks of storage, extractibilities of salt soluble protein were decreased by 17.7%, 6.1% and 1.6% at freezing rates of 0.97, 2.05 and 3.71cm/hr, respectively. On the other hand, extractabilities of water soluble protein were decreased by 26.0%, 21.2% and 18.5%, respectively. The effect of freezing rates on the protein extractability appeared to be greater in salt soluble protein than in water soluble protein, but freezing denaturation was more rapid in water soluble protein.

• Journal of the Korean Geotechnical Society
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• v.27 no.12
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• pp.17-25
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• 2011

A fabric of soil media may change due to certain factors such as dissolution of soluble particles, desiccation, and cementation. The fabric changes affect the mechanical behavior of soils. The purpose of this study is to investigate the effects of geo-material dissolution on shear strength. Experiments and numerical simulations are carried out by using a conventional direct shear and the discrete element method. The dissolution specimens are prepared with different volumetric salt fraction in sand soils. The dissolution of the specimens is implemented by saturating the salt-sand mixtures at different confining stresses in the experimental study or reducing the sizes of soluble particles in the numerical simulations. Experimental results show that the angle of shearing resistance decreases with the increase in the soluble particle content and the shearing behavior changes from dilative to contractive behavior. The numerical simulations exhibit that macro-behavior matches well with the experimental results. From the microscopic point of view, the particle dissolution produces a new fabric with the increase of local void, the reduction of contact number, the increase of shear contact forces, and the anisotropy of contact force chains compared with the initial fabric. The shearing behavior of the mixture after the particle dissolution is attributed to the above micro-behavior changes. This study demonstrates that the reduction of shearing resistance of geo-material dissolution should be considered during the design and construction of the foundation and earth-structures.

• Korean Journal of Agricultural Science
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• v.8 no.2
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• pp.231-237
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• 1981

In order to obtain the basical data for utilization of protein in hazel nut, protein was extracted from defatted hazel nut meal with salt solutions and alkaline solutions, and precipitated by adjusting pH of extract to 5.5 or addition of organic solvents. Amino acid composition of the isolated protein and defatted hazel nut meal were analyzed, protein isolates were identified by polyacrylamide gel electrophoresis. The results summarized were as follows. 1. Defatted hazel nut showed highly nutritional value as the content of 'protein was 53.6%. 2. Extractabilities of salt-soluble protein treated with 2.5M $MgCl_2$, and 1M NaCl(pH 11.0) were 53.0%, 31.5%, respectively 3. Protein in hazel nut were contained 53% of salt-soluble globulin, 14% of water-soluble albumin, 29.5% of glutelin based on solubility. 4. At pH 5.5, 85% of the extracted protein was precipitated, and about 90% of the extracted protein was separated by addition of organic solvents such as acetone and ethanol at 60-70% concentration. 5. Proteins extracted from defatted hazel nut with water and 0.027N NaOH showed 3 and 6 hands by polyacrylamide gel electrophoresis, respectively. 6. Amino acids of defatted hazel nut and protein isolate were chiefly composed of glutamic acid, arginine and aspartic acid.