• Korean Journal of Agricultural Science
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• v.18 no.1
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• pp.33-40
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• 1991

This study was performed to obtain the basic data applied to use of synthetic lightweight aggregate concrete affected by alkali silica reaction. The results obtained were summarized as follows; 1. The compressive strength of type A concrete was increased with increase of curing age. At the curing age 28 days, the highest compressive strength was showed at type Band C concrete, respectively. But, it was gradually decreased with increase of curing age at those concrete. 2. The flexural strength of type A concrete was increased with increase of curing age. At the curing age 14 days, the highest flexural strength was showed at type Band C concrete, respectively. But, it was gradually decreased with increase of curing age at those concrete. 3. The correlation between compressive and flexural strength of the sample was shown highly significant only at type A concrete. 4. It was shown that the water absorptions of the type Band C were 7.0-7.8 times higher than the type A concrete. It was significantly higher at the early stage of immersed time at all sample. 5. The correlation between compressive strength and water absorption of the sample was significant only at the type A concrete.

• Food Science of Animal Resources
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• v.23 no.1
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• pp.21-27
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• 2003

This study was carried out to investigate the effect of curing method(tumbling and immersion) and curing time (10 min to 48 hrs) on pH, color, product yield, cooking yield, water holding capacity, shear force, and sensory evaluation of cured pork meat with soy sauce. Curing method had an effective on color of cured meat(before cooking), Meats were tumbled for 30 min, followed by 24 hr and 48 hr delay period showed higher lightness than meat immersed for 24 and 48 hrs, respectively. Tumbling processing improved product yield and cooking yield as compared to immersion counterpart. Therefore, tumbled meat had significantly greater product yield(p <0.05) during working time for 30 min. Increasing curing time improved water holding capacity and tenderness. Although curing time had no influence on sensory evaluation, tumbling processing improved sensory evaluation of texture, juiciness, and overall acceptability fer cured pork meat with soy sauce, as compared to immersion counterpart.

• Journal of the Korea Institute of Building Construction
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• v.15 no.3
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• pp.281-289
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• 2015

Carbonation of concrete causes reduction of pH and subsequently causes steel corrosion for reinforced concrete structure. However, for plain concrete structure or PC product, it can lead to a decrease in porosity, high density, improvement of concrete, shrinkage-compensation. Recently, based on this theory, research of $CO_2$ curing effect has been performed, but it was mainly focused on its effects on compressive strength using only ordinary portland cement. Researches on $CO_2$ curing effect for concrete containing $CO_2$ reactive materials such as ${\gamma}-C_2S$, MgO haven't been investigated. Therefore, this study has performed experiments under water-binder ratio 40%, and the replacement ratios of ${\gamma}-C_2S$ and MgO were 90%. Micro-chemical analysis, measurement of compressive strength according to admixtures and $CO_2$ curing were investigated. Results from this study revealed that higher strength was measured in case of $CO_2$ curing compared with none $CO_2$ curing for plain specimen indicating difference between 1.08 and 1.26 times, in case of ${\gamma}-C_2S$ 90, MgO 90 specimen, incorporating high volume replaced as much as 90%, it was proven that when applying $CO_2$ curing, higher strength which has difference between 14.56 and 45.7 times, and between 6.5 and 10.37 times was measured for each specimen compared to none $CO_2$ curing. Through micro-chemical analysis, massive amount of $CaCO_3$, $MgCO_3$ and decrease of porosity were appeared.

• Journal of the Korean Recycled Construction Resources Institute
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• v.4 no.4
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• pp.91-98
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• 2009

Recently, production cost of ready mixed concrete has been increased due to the rising cost of raw materials such as cement and aggregate etc. cause by the upturn of oil price and increase of shipping charge. The delivery cost of ready mixed concrete companies, however, has been decreased owing to their excessive competition in sale. Consequently, ready mixed concrete companies began to manufacture the concrete by mixing ground granulated blast furnace slag(GGBF) and fly-ash in order to lower the production cost. Therefore, the objective of this study was to predict 28 days strength of GGBF slag concrete by early strength(warm and hot water curing method) for the sake of managing with ease the quality of ready mixed concrete. In experimental results, the prediction equation for 28 days compressive strength of GGBF slag concrete could be produced through the linear regression analysis of early strength and 28 days strength. In order to acquire the reliability, all mixture were repeated as 3 times and each mixture order was carried out by random sampling. The prediction equation for 28 days strength of GGBF slag concrete by 1 day compressive strength(accelerated testing) according to warm and hot water curing method won the good reliability.

• Proceedings of the Korean Geotechical Society Conference
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• 1999.11c
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• pp.143-155
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• 1999

An experimental study has been carried out to investigate the reinforcing effect of marine dredging clay(MDC) mixed with the Micro-Fiber(MF). A series of laboratory tests was performed using specimens of MDC alone and MDC with MF by means of uniaxial and triaxial compression test. In the test programme, three stages of water content of MDC were chosen according to the elapsed time after dredging, and content and length of MF were considered as important factors for reinforcing effect. And the developed strength due to curing was measured both in MDC and composite. The enhancement of strength of composite was found to be increased with the increasing content and length of MF, and curing time, and with decreasing water content of MDC. An additional study has been made for in-situ trafficability on the soft reclaimed ground by MDC due to high water content. It was found that the waste lime was to be applicable for this purpose to get a reinforcing effect of MDC. A further study would lead to the better understanding of the reinforcing mechanism of the composite.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.31 no.6 s.261
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• pp.499-506
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• 2007

This study aims to propose evaluation methods of chemical washing performance and estimate the washing capability by flowing detergent/water solution for application to home appliances such as dishwashers. Standard pollutant is stearic acid. A numerical study is also tried using a SIMPLER code. Preliminary experiments are performed by varying the concentration and temperature of the solution. From the pre-experiments, 10 minute pre-curing time is found to be necessary to remove the stearic acid. Stoichiometric ratio and detergent consumption coefficient of reaction between the detergent and stearic are estimated following a proposed method. Washing experiments of pollutant to compare with the numerical results are performed. The relative errors between the experimental and the numerical results with pre-curing time included are less than 7%. In conclusion, important mechanisms of chemical washing are revealed and methods of predicting washing performance are well established.

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.1038-1039
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• 2004

We developed a new photoresist which was composed of polyaniline, uv-curing agent, N-methyl-2- pyrrolidine (NMP) and N-Butyl alcohol (BuOH) as solution. The photoresist is characterized by the capability of being developed in water. We successfully patterned pentacene thin film, which was vulnerable to organic solvent and thus could not be patterned by the conventional photolithography process, with the water soluble photoresist and the minimum feature size was found to be 2um.

• The Korean Journal of Food And Nutrition
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• v.16 no.3
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• pp.171-179
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• 2003

In order to investigate the effects of pickle carrier on physico-chemical characteristics of seasoning chicken products, chicken were cured in seasoning containing 100 ppm germanium water, green tea, water soluble mineral and mixtures(100 ppm germanium water+green tea+water soluble mineral) after addition of 0.1% concentration to the weight of chicken. The determination of pH, salt and sugar contents were carried out, according to curing time. The salt content showed 1.11 %, 1.21 % in cured at 24 hours in control of breast and leg, irrespective of chicken parts, in which showed 19.94 brix, 18.89 brix in sugar content, respectively. These results mean that breast and leg meat added with natural extracts and functional water showed higher sugar content than that of control, in which revealed shortening of curing time by increasing penetrating velocity of salt and sugar content. Thus, salt and sugar content tended to be increased as the curing time of pickle carrier were extended in seasoning chicken after dipping in pickle containing water soluble mineral ions for 6 hours. The seasoning chicken treated with natural extracts and functional water showed a lower than that of control in hardness, irrespective of chicken parts. Overall, the seasoning chicken treated with natural extracts and functional water showed a low TBARS value and Log CFU/g, in which revealed antioxidative and antimicrobial activity. The sensory evaluations of seasoning chicken added with natural extracts and functional water containing water-soluble mineral ions were not significantly different(P<0.05). The glutamic acid among free amino acid contents showed a high in seasoning chicken treated with green tea, compared to control. This amino acid played a important role in taste of seasoning meat. The doneness appearance in seasoning chicken added with natural extracts and functional water containing water-soluble mineral ions tended to not be different, compared to those of control. These results revealed that seasoning chicken added with natural extracts and functional water containing water-soluble mineral ions would be attractive in fast food market on the basis of improvement of tenderness, shortening of curing time and uniformity of roasting appearance in seasoning chicken.

• Restorative Dentistry and Endodontics
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• v.14 no.1
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• pp.41-56
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• 1989

The purpose of this study was to examine the effect of temperature dependence of the behavior on the physical properties of posterior composite resins. Three light cure posterior composite resins (Heliomolar, Litefil-P, and P-50) and one chemical cure posterior composite resin (Bisfil-II) were used as experimental materials. Composite resin was placed in a cylindrical brass mold (2.5 mm high and 6.5 mm inside diameter) that was rested on a glass plate. Another flat glass was placed on top of the mold, and the plate was tightly clamped together. After the mold had been filled with the light cure composite material, the top surface was cured for 30 seconds with a light source. Chemical cure resin specimens were made in the same manner as above. Three hundreds and twenty composite resin specimens were constructed from the four composite materials. One hundred and sixty specimens of them were placed in a heater at $50^{\circ}C$, $75^{\circ}C$, $100^{\circ}C$, $125^{\circ}C$, $150^{\circ}C$, $175^{\circ}C$ and $200^{\circ}C$ for 5 minutes or 10 minutes respectively before compressive strengths were measured. Another one hundred and sixty specimens were tested for the diametral tensile strengths in the same way as above. They were randomly divided into eight groups according to the mode of heating methods as follows and stored in distilled water at $37^{\circ}C$ for 24 hours. Group $37^{\circ}C$ - specimens were stored at $37^{\circ}C$ in distilled water for 24 hours. Group $50^{\circ}C$ - specimens were heated at $50^{\circ}C$ after curing. Group $75^{\circ}C$ - specimens were heated at $75^{\circ}C$ after curing. Group $100^{\circ}C$ - specimens were heated at $100^{\circ}C$ after curing. Group $125^{\circ}C$ - specimens were heated at $125^{\circ}C$ after curing. Group $150^{\circ}C$ - specimens were heated at $150^{\circ}C$ after curing. Group $175^{\circ}C$ - specimens were heated at $175^{\circ}C$ after curing. Group $200^{\circ}C$ - specimens were heated at $200^{\circ}C$ after curing. Twenty specimens of each of four composite resins were respectively made by insertion of materials into same mold for examining the dimensional changes between before and after heating. The final eighty specimens were stored in distilled water at $37^{\circ}C$ for 24 hours before testing the dimensional changes. Compressive and diametral tensile strengths were measured crosshead speed 1mm/minute and 500Kg in full scale with a mechanical testing machine (DLC 500 Type, Shimadzu Co., Japan). Dimensional changes were determined by measuring the diametral changes of eighty specimens with micrometer (Mitutoyo Co., Japan). Results were as follows: 1. Diametral tensile strengths of specimens in all groups were increased with time heated compared with control group except for that in group $50^{\circ}C$ and the maximum diametral tensile strength was appeared in the specimen of Litefil-P heated for 10 minutes at $100^{\circ}C$. In heliomolar and P-50, it could be seen in the specimen heated for 10 minutes at $150^{\circ}C$, but in Bisfil-II, it could be found in the specimen heated for 5 minutes at $150^{\circ}C$. 2. Compressive strengths of specimens in all groups was tended to be also increased with time heated but that in group $50^{\circ}C$ and the maximum compressive strengths were showed in the same specimens conditioned as the diametral tensile strengths of four composite materials tested. 3. In Heliomolar, Litefil-P, and Bisfil-II, it was decreased in diameters of resin specimens between before heating and increased in diameters of resin specimens after storing in distilled water, but it was not in P-50. 4. There is little difference in diametral tensile strengths, compressive strengths, and dimensional changes followed by heating the resin specimens for 5 minutes and 10 minutes, but there is no statistical significances.

• Journal of the Korean Society of Food Science and Nutrition
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• v.19 no.2
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• pp.133-142
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• 1990

This study was attempted to compare the nutritive value of leaf with stem of the water cress Oenanthe stolonifera DC. in order to improve the eating habits and as a part of studying on the effective curing nutrients for the damaged liver. The contents of moisture crude proteinon the effective curing nutrients for the damaged liver. The contents of moisture crude protein crude fat and crude ash were 90.40% 2.85%, 0.42% and 0.74% in leaf while the contents of moisture crude protein crude fat and crude ash were 95.15% 0.77% 0.09%, and 0.64% of moisture crude protein crude fat and crude ash were 95.15% 0.77% 0.09% and 0.64% in stem respectively. The quantitative fractionation of proteini of both leaf and stem ranked albumin the highest content followed globulin prolamin and glutelin in order. It has been sh-own by SDS-polyacrylamide gel electrophoresis that water extractable protein of leaf 11 bands but those of stem were not detected. The scope of molecular weight for the main protein of water extractable protein of leaf was between 34.700 and 45,000. The amounts of extractive-nitrogen from leaf and stem of the water cress were 241.02mg% and 271.67mg% respec-tively. The amounts of free amino acid-nitrogen from the leaf and stem were 89.02mg% and 32.02mg% respectively. In free amino acid-nitrogen from the leaf and stem were 89.02mg% and 32.02mg% respectively. In free amino acid composition of both leaf and stem the major components were aspartic acid and glutamic acid. In total amino acid composition of water cress leaf aspartic and glutamic acid were the major components. Whereas alanine and thr-eonine were the major components in stem The assessment of water cress leaf and stem with chemical score. EAAl Rl showed that the values of stem were lower tendancy than those of leaf. Limiting amino acid of leaf was tryptophan while that of stem was lysine.