• Journal of Korea Foundry Society
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• v.7 no.4
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• pp.366-379
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• 1987

The influences of some factors on the variation of compression strength of $CO_2$ process were investigated with an attention given to use of high $SiO_2\;/Na_2O$ silicate, addition of organics and gassing operation. 1) Higher ratio binder offers faster rates of hardening with lower $CO_2$ consumption requiring more concentration for a good strength development. A mixture containing 4 percent of 2.7:1 ratio silicate produces the strength above $8kg\;/\;cm^2$ after 80 seconds gassing, but 5% and 6% respectively of 3.0:1 and3.3:1 ratio silicate are necessary to achieve equivalent levels of strength. 2) The correct water content in sand mixtures containing higher ratio silicates is necessary for the better strength properties to be obtained. The addition of 1% water to the sand mixtures bonded with 5%,3:1 ratio and 6%,3.3:1 ratio silicates maintains near-maximum strength on extended gassing. 3) When higher ratio silicates with 3:1 and 3.3:1 ratios are used,the addition of organic additives such as oil, sucrose and polyol results in considerable changes in strength. The presence of 1.0 to 1.5 percent of polyol produces a noticiable improvement 4) Gas diluted with air raises the efficiency of gas utilization. When gas contains 50 percent $CO_2$, the efficience is significantly increased with the best strength in the silicates having high ratios of 3:1 and 3.3:1. 5) The strength of molds is liable to change on storage with the reduction in water content. The magnitude of the strength change is determinded with the mole ratio. The presence of polyol in the mixture with 3.3:1 ratio silicate has a pronounced effect on maintaining the gassed strength.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.39 no.9
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• pp.917-922
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• 2015

The goal of this study is to consider the application of alternative blended fuel to diesel engine. In this study, as the test fuels, we use a blended fuel mix of diesel and hydrogen peroxide. As the primary variable, we vary the mixing ratio of diesel and hydrogen peroxide in the experimental and numerical analysis. We perform an evaporative behavior characteristics analysis of the emulsified fuel using the Schlieren method. The numerical analysis was carried out based on results obtained from the experimental analysis using the commercial code(ANSYS CFX). Consequently, we found that the micro-explosion depends on the fraction of hydrogen peroxide, and we propose a numerical method for the quantitative evaporation analysis of emulsified fuel droplets using the calculation of the volume fraction in the oil domain.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.10 no.4
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• pp.15-24
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• 2014

This study conducted a computational fluid dynamics(CFD) analysis to find an appropriate diameter or sectional area of air ducts and fluid pipes which have an electromagnetic pulse(EMP) shied to protect indoor electronic devices in special buildings like military fortifications. The result shows that the optimized outdoor air intake size can be defined with either the ratio of the maximum air velocity in the supply duct to the air intake size, or the shape ratio of indoor supply diffuser to the outdoor air intake. In the case of water channel, the fluid velocity at EMP shield with the identical size of the pipe, decreases by 25% in average due to the resistance of the shield. The enlargement of diameter at the shield, 2 step, improves the fluid flow. It illustrated that the diameter of downstream pipe size is 1step larger than the upstream for providing the design flow rate. The shield increases friction and resistance, in the case of oil pipe, so the average flow velocity at the middle of the shield increase by 50% in average. In consideration of the fluid viscosity, the oil pipe should be enlarged 4 or 5 step from the typical design configuration. Therefore, the fluid channel size for air, water, and oil, should be reconsidered by the engineering approach when EMP shield is placed in the middle of channel.

• Analytical Science and Technology
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• v.11 no.2
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• pp.79-87
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• 1998

Consumers have recently preferred to purchase extensive UV intercepting products, which are waterproof and free from side effects on skin. During the testing of cytotoxicity (in-vitro) in neutral red (NR) method, cell survival ratio of UV-B interceptors decreased to just above 0.08 w/v%, and it was observed that the UV-A interceptors the ratio also decreased to just above 0.06 w/v%. In addition patch-tests of inorganic UV interceptors resulted in no skin irritation even below 10.0 and 11.25. In absorption curves, UV-B was most suitable for octyl methoxycinnamate (OMC) and UV-A for butyl methoxy dibenzoylmethane (BMDM). For this reason, $Nylonpoly^{TM}$ UVA/UVB the material of OMC and BMDM coated with Nylon & polyethylene, was used as the organic UV interceptor. Zinc oxide (ZnO) and titanium dioxide ($TiO_2$) was used as inorganic UV interceptors. The appropriate mixture ratio of ZnO and $TiO_2$ was 6 to 4:6% of ZnO, 4% of $TiO_2$ and 5% of $Nylonpoly^{TM}$ UVA/UVB were all combined and added to our sunscreen cream. The SPF value of in-vitro was 38.9. In practical application, each sun protection factor (SPF) duration of oil-in-water (O/W) emulsion and water-in-silicone (W/S) emulsion containing sunscreen cream of the same content showed that W/S type of sunscreen cream was 5 times as durable as the other. Therefore, this product is fit for use in swimming, climbing or skiing. This research is to minimize skin trouble caused by UV interceptors and to make one with proper softness, skin safety and UV intercepting efficiency.

• Applied Biological Chemistry
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• v.40 no.4
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• pp.318-322
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• 1997

As an investigation for utilization of squid viscera oil as a food source, we attempted to improve a quality of fish burger by addition of emulsion curd formed from gelatin, water and refined squid viscera oil. Judging from the results of peroxide value, brown pigment formation, color value of Hunter, jelly strength and sensory evaluation, the reasonable amount of emulsion curd for the improvement of a fish burger functionality was determined as 6% on the weight basis of the chopped mackerel meat. Total plate counts, volatile basic nitrogen and histamine contents in fish burger prepared by addition of 6% of emulsion curd were $6.2{\times}10^4\;CFU/g$, 19.0 mg/100 g, and 50.7 mg/100 g, respectively. It may be concluded, from the above results that the emulsion curd-added fish burger is a safe as a food commodity. The ratio of polyenes to saturates of emulsion curd-added mackerel burger was 1.13. By adding emulsion curd formed from gelatin, water and refined squid viscera oil, color in cross section, texture and lipid functionality of mackerel burger could be improved in part.

• Korean Journal of Veterinary Service
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• v.16 no.2
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• pp.127-137
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• 1993

Carbon tetrachloride ($CCl_4$) has been used to treat a variety of parasitic infection in both large and small animals, including Fasciola hepatica. Recently, we can easily contest with carbon tetrachloride in air, food, water, rain and Industry area etc. and it is using in order to induce liver injury in laboratory. In this study. we investigated activitis of LDH, ALP, AST and ALT and amount of cholesterol, triacylglycerol, glucose and BUN in mice serum exposed to $CCl_4.$ The mice divided Into a Naive control(A), corn oil control(B) and experimental group(C, D). Naive control group(A) was given feed and water only. Corn oil control group(B) was given corn oil 1ml /100g of body weight(B.W). Experimental group(C) was given carbon tetrachloride 1ml /100g B.W. ($CCl_4$： corn oil=1：20(V /V) ), Experimental group(D) was given carbon teterachloride 1ml /100g B.W. ($CCl_4$: corn oil=1：10(V /V) ). The results obtained were summarized as follows : 1) The body weight was declined after the l0th day In mice exposed to carbon tetra-chloride. 2) The total protein level in serum was significantly in mice exposed to carbon tetra-chloride($P{\leq}0.05$). The albumin and A /G ratio was decresed significantly in mice exposed to carbon tetrachloride($P{\leq}0.01$) 3) All of the activity of LDH, AST, ALT and ALP in mice serum exposed to carbon tetra chloride inclosed significantly activity of LDH ($P{\leq}0.05$), inclosed significantly activity of AST($P{\leq}0.05, \;p {\leq}0.01$), inclosed significantly activityof ALT 3nd ALP($P {\leq}0.05,\;p {\leq}0.01$). 4) The amount of cholesterol and triacylglycerol, lipid metabolite products in serum was inclosed in case of cholesterol but did not change in case of triacylglycerol.

• Korean Journal of Food Science and Technology
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• v.51 no.6
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• pp.531-536
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• 2019

In this study, the optimization of the manufacturing process for the oil-in-water emulsification of rice bran oil was performed by response surface methodology (RSM) using varying amounts of the emulsifier (0.05-0.25%), varying rotation speeds of the homomixer (4,000-8,000 rpm), and varying water to oil ratios (0.8-1.6%) as independent variables, and the emulsion stability index (ESI) as the dependent variable. The optimization conditions predicted by the RSM model were 0.2%g of the total amount of the rice bran oil emulsion, emulsified at the homomixer rotation speed of 6,700 rpm using a water to oil ratio of 1:3. The ESI of the rice bran oil emulsion prepared under the optimized conditions was 95.7%, which was similar to the predicted value of 94.4% obtained by the RSM model. The transmission stability and the backscattering values were found to agree with each other over time and the turbiscan stability index was less than 0.7, indicating that the aggregation and upper floatation were less while the dispersion stability was maintained.

• Korean Journal of Food Science and Technology
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• v.23 no.2
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• pp.248-250
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• 1991

This study was carried out to find out the color, rooking quality and storability of the oil-added milled rice. Soybean oil was added at the level of $0.07{\sim}0.15%$ in the last cycle of milling process. Fat content of the oil unadded milled rice was 0.65% and that of the oil-added one were 0.70% to 0.73%. Water uptake ratio, expanded volume, total soluble solids and iodine blue value of milled rice during cooking were lower in the oil-unadded one. The oil-addition to milled rice lowered the value of Hunter L, a, b and whiteness. Changes in fat acidity of the oil-added milled rice was similar to that of the untreated rice.

• Journal of ILASS-Korea
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• v.10 no.3
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• pp.9-16
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• 2005

To investigate spray and combustion of emulsified fuel of W/O type, we mixed water with light oil by using ultrasonic energy adding system. We measured the SMD of sprayed droplet to find atomization characteristics of emulsified fuel with using the Malvern 2600D system. Major parameters are the weight ratio of water($0{\sim}30%$ by 10%) in emulsified fuel injection pressure(lobar), and the measurement distance($10{\sim}100mm$ by 10mm). Combustion visualizing system is made up commonly used boiler system and digital camera 1/500s to investigate combustion phenomena. As a result, the more water contents increased, the more SMD increased. The water particle of emulsified fuel made short flame in continuos spray combustion phenomena because of micro explosion.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.24 no.3
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• pp.116-122
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• 1998

It is well known that all-trans-retinol is not only very unstable in heat, light, air, and water, but also skin-irritant despite a good anti-wrinkle effect. Therefore, it is very difficult to stabilize retinol and make the safe retinol containing cosmetics by using a certain concentration of retinol with real effect. In order to dissolve these problems and apply retinol for skin care cream, firstly retinol is to be encapsulated in the vesicle called Liposphere (pseudo-liposome) which is made by homogenizing under high pressure the mixtures of lecithin, retinol, caprylic/capric triglyceride, and hydroalcoholic solution ; and then this retinol containing Liposphere is to be intercalated in lamellar liquid crystal layer which is prepared by emulsifying in an optimal ratio the mixtures composed of non-ionic emulsifier (cetearyl glucoside, sorbitan stearate & sucrose cocoate etc), cetearyl alcohol, stearic acid, cholesterol, and ceramide. In addition, the stability of the retinol containing oil in water cream by adding the polymeric emulsifier such as acrylate /C10-30 alkyl alkylate crosspolymer is to be ensured even at 55 C. Retinol containing oil in water cream prepared through above procedure could be very stable at 45 C for at least 50 days. The structure identification of lamellar liquid crystal was determined using polarized light microscope and electron microscope Conclusively, we could make the very stable retinol containing oil in water cream by triple procedure, that is, encapsulation of retinol in Liposphere, intercalation of retinol in lamellar liquid crystal layer, and assurance of the high temperature stability of cream even at 55 C.