• The Journal of Engineering Geology
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• v.26 no.4
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• pp.515-529
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• 2016

In this study, geochemical composition, CFCs (Chlorofluorocarbons), ${\delta}^{18}O$, ${\delta}D$, ${\delta}^{13}C$ isotopes and noble gases isotopes (He, Ne) were analyzed to determine their recharge age, source of $CO_2$ gas and noble gases of carbonated hot spring water and carbonated-water samples collected in the Seoqwipo of the Jeju. The pH of the carbonated waters ranges from 6.21 to 6.84, and the high electrical conductivity range ($1,928{\sim}4,720{\mu}S/cm$). Their chemical composition is classified as $Mg(Ca,\;Na)-HCO_3$ and $Na(Ca,\;Mg)-HCO_3$ types. As a result of the calculation of groundwater age using CFCs concentrations as an environmental tracer, the carbonated water and groundwater were estimated to be about 47.5~57.2 years and about 30.3~49.5 years, respectively. The ${\delta}^{13}C$ values of carbonated water range from -1.77 to -7.27‰, and are plotted on thr deep-seated field or the mixing field of the deep-seated and inorganic origin. Noble gases isotopic ($^3He/^4He$, $^4He/^{20}Ne$) ratio shows that helium gas of carbonated hot waters comes from deep-seated magma origin.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05b
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• pp.185-188
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• 2006

During the carbonation process in concrete, the rate of carbonation depends on porosity and moisture content of the concrete. For underground reinforced concrete structures, the interior concrete surface may be exposed to carbonation and the exterior concrete surface exposed to moisture due to wet soil or underground water. In this study, the permeability coefficients in mortar partially carbonated is derived as a function of carbonation depth and porosity of mortar by applying the so-called micro pore structure formation model (MPSFM) which was developed for the modeling of early-aged concrete. The permeability coefficient obtained from the micro-level modeling of carbonated mortar is verified with the results of accelerated carbonation test and water penetration test in cement mortar.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2008.10a
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• pp.123-125
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• 2008

Enamel layer consists of carbonated hydroxyapatite of 85%, water of 12% and protein of 3% and lipid and tentin consists of carbonated hydroxyapatite of 47%, water of 20% and protein of 33% and lipid so if heat is increased in teeth and then teeth color is discolor. In case high temperature is applied in teeth, teeth color changed quality is measured about change of time for minimize teeth change of color. Spectroscopic light intensity special quality by change of time rise at specification temperature.

• The Korean Journal of Food And Nutrition
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• v.31 no.2
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• pp.293-300
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• 2018

The purpose of this study was to investigate dietary habits, health lifestyle, preference and intake of beverages of Chinese students in Gyeonggi area. Therefore, we try to identify the factors that affect beverage consumption. According to the analysis of the demographic characteristics of male and female Chinese students, there were 155 male students (49.7%) and 157 female students (50.3%). There were statistically significant differences between the residence period and the time of coming to Korea according to sex (p<0.05), but there was no statistically significant difference between the education level, residence type and Korean ability (p>0.05). Analysis of the differences in health-related lifestyle among Chinese students of both sexes showed statistically significant difference in alcohol drinking, smoking, and exercise according to sex (p<0.05), but no statistically significant difference in computer use time (p>0.05). According to the analysis of the dietary habits of the Chinese students, there was a statistically significant difference in the number of meals per day, breakfast, lunch, dinner, snack frequency and number of midnight snacks, but no statistically significant difference in eating out frequency. As a result of the preference test for general beverages, 4.11 points of water, 3.81 points of milk, 3.64 points of fruit and vegetable juice, 3.58 points of tea, 3.25 points of coffee, 3.22 points of carbonated drinks, 2.92 points of functional drinks, respectively. Male students were more likely to prefer water, tea, and health functional drinks while female students had higher preference for fruit, vegetable juice and vinegar drinks (p<0.05). In general, consumption of regular drinks was 4.95 in water, 3.58 in milk, 3.03 in coffee, 2.92 in carbonated drink, 2.91 in fruit and vegetable juice, 2.63 in tea, 2.07 in functional drink, and 1.44 in vinegar appear. Male students had higher intake of water, tea, carbonated drinks, and health functional drinks while female students had higher intake of fruit and vegetable juice (p<0.05). The results of correlation analysis of factors affecting the general drinking of Chinese students are as follows. The intake of tea was related to the period of residence and dietary habits, the intake of milk for breakfast, the number of snacks and midnight snacks for carbonated drinks, and the fruit vegetable juice were related to dietary habits (p<0.01, p<0.05).

• Computers and Concrete
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• v.15 no.6
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• pp.973-987
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• 2015

The electrical resistivity of air-dried, saturated, and carbonated concretes with different mixture proportions was monitored to evaluate and quantify the influence of the age of the specimen, carbonation, and curing condition. After 28 days of curing, four prepared specimens were stored in a vacuum chamber with 5% $CO_2$ for 330 days to make carbonated specimens. Four of the specimens were placed in water, and four specimens were cured in air until the end of the experiments. It was observed that the electrical resistivity of the carbonated specimens increased as carbonation progressed due to the decrease of porosity and the increase of hydrated products. Therefore, in order to estimate the durability of concrete, its carbonation depth was used as the measurement of electrical resistivity. Moreover, an increase of electrical resistivity for air-dried and saturated concretes was observed as a function of age of the specimen. From the relationship between chloride diffusivity provided by Yoon et al. (2007) and the measurements of electrical resistivity, it is expected that the results well be of significant use in calibrating chloride diffusivity based on regular measurements of electrical resistivity during concrete construction.

• Journal of the Korean Ceramic Society
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• v.55 no.2
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• pp.160-165
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• 2018

This paper investigates the reaction rate of $CO_2$ storing carbonation hybrid reaction by comparing the behavior of carbonation between $Ca(OH)_2$ and fly ash with that of CFBC (Circulating Fluidized Bed Combustion) containing plenty of Free-CaO. Because fly ash with CFBC contains a lot of unreacted CaO, it cannot be used as a raw material for concrete admixtures and its usages are limited. To reuse such material, we stabilized unreacted CaO by carbonation and investigated the carbonation rate. We used a pH meter and a thermometer to check the rate of the carbonization. Also, we set the contents of fly ash with CFBC, $Ca(OH)_2$, flow and fluid of $CO_2$, respectively, to 100 g, 50 g, 100 ~ 1000 cc/min and 400 g based on the content of Free-CaO. We used carbonated water instead of water, and added an alkaline activator to promote the carbonation rate. As a result, the addition of the alkaline activator and carbonated water promoted the rate of carbonation via a hybrid reaction.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.1053-1056
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• 2008

Permeability coefficient of concrete is a substantial key parameter for understanding the durability performance of concrete and its micro-structural densification. Many researches to deal with the issue have been accomplished, however, it is very rare to deal with the theoretical study on permeability coefficient in connection with carbonation of concrete and the effect of volumetric fraction of cement paste or aggregate on the permeability coefficient. The majority of these researches have not dealt with this issue combined with carbonation of concrete, although carbonation can significantly impact on the permeability coefficient of concrete. The purpose of this study is to establish a fundamental approach to compute the permeability coefficient of (non)carbonated concrete. When simulating micro-structural characteristics as a starting point for deriving a model for the permeability coefficient by the numerical simulation program for cementitious materials, HYMOSTRUC, a more realistic formulation can be achieved. For several compositions of cement pastes, the permeability coefficient is calculated with the analytical formulation, followed by a microstructure-based model. Emphasis is on the micro-structural changes and its effective change of the permeability coefficient of carbonated concrete. The results of micro-structural water permeability coefficient model will be compared with results achieved from permeability experiments.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.3
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• pp.420-428
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• 1994

The purpose of this study was to determine relationship among the observed frequencies of 12 beverages selected by college men and women according to sex, age, race and academic classification and to estimate consumption of milk according to sex, age, race and academic classification. The instrument consisted of a check list and four questions. The sample of 282 subjects, 149 college men and 133 college women, was made by the accidental choice method. Observations occurred in the university center cafeteria at the dinner meal. The significant relationship s were sex and race in association with beverage selections by all subjects. The proportion of men in the distribution who selected regular , carbonated soft drinks and the proportion of white students who selected any of the carobnated soft drinks were the influencies. The result of the study indicated that carbonated soft drinks were the most preferred items followed by milk, water, iced tea, fruit juices, coffee, cocoa, and tea.

• Journal of Korean Home Economics Education Association
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• v.30 no.4
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• pp.83-91
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• 2018

This study was performed to measure the liquid intake and the liquid intake difference by obesity, exercise frequency, and salty food intake score in female high school students. A total of 235 students in Daejeon area were participated, and the liquid intake was recorded for 3-days(2 weekdays and 1 weekend) by self-recording. The T-test, F-test, Pearson's correlation, and Scheffe test were exercised. The results of this study are as follows. The amount of total liquid intake was 838.5 ㎖/d. Among the 13 kinds of beverages, water was the highest 611.6 ㎖/d, 72.9% of liquid intake total, followed by carbonated drink(65.7 ㎖/d), milk(41.6 ㎖/d), fruit drink(32.8 ㎖/d), and fruit·vegetable juice(25.4 ㎖/d). The other beverages' intake were very small, ≤13.0 ㎖/d. Carbonated drink, milk, and coffee's intake were higher during weekend than weekday. There were sig. difference in water and total liquid intake by the obesity, student of BMI≥23.0 was higher than students of BMI<23.0. And only carbonated drink was sig. different by exercise frequency and salty food intake score. Exercise frequency of ≥3 d/week and salty food intake score of ≥7(very dangerous) consumed more carbonated drink than the lower counterparts. Total liquid intake of female high school students was not reach to 900 ㎖/d, the Adequate Intake in Dietary Reference Intake for Koreans 2015. The amount of milk intake was 41.6 ㎖/d, far less than the Recommended Intake of 2 serving, 400 ㎖/d. Education and promotion program may necessary to increase the liquid intake amount and to choose the nutritious beverage.

• Nutrition Research and Practice
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• v.10 no.5
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• pp.546-554
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• 2016

BACKGROUND/OBJECTIVES: The aim of this study was to investigate the perception of sugar reduction, nutrition education, and frequency of snacking in children according to the self-perceived dietary preferences for sweet taste by mothers in Busan. SUBJECTS/METHODS: A total of 277 mothers were surveyed, and their perceptions of sugar reduction and the frequency of snacking in children were assessed using a questionnaire. The subjects were classified into either a sweet (n = 91) or an unsweet (n = 186) group according to their self-perceived preferences for a sweet taste. RESULTS: In the sweet group, the results for sweet products were sweetened ice (86.8%), confectionery (74.7%), processed milk (73.6%), carbonated beverages (71.4%), and fermented milk (53.9%). In the unsweet group, the results were sweetened ice (88.7%), carbonated beverages (78.5%), processed milk (75.8%), confectionery (69.4%), and fermented milk (50.5%). The necessity of sugar intake reduction was high in both groups (sweet = 89.0%, unsweet = 82.8%). Beverage purchases after identifying the nutrition labeling was significantly lower in the sweet group than in the unsweet group (P < 0.05). The reasons for the beverage purchases instead of water were "habitually" (50.5%) and "like sweet taste" (25.3%) in the sweet group (P < 0.01). Snacking in children was significantly higher in the sweet group based on the increased frequencies of carbonated drinks (P < 0.01), fast food (P < 0.001), candy and chocolate (P < 0.05), crackers (P < 0.01), ramen (P < 0.01), and fish paste/hotdogs (P < 0.01). The frequency of purchase education after identifying the nutrition labeling was significantly lower in the sweet group than in the unsweet group (P < 0.01). CONCLUSIONS: These findings suggest that a perception of sugar reduction and practical nutrition education aimed at reducing the sugar intake are necessary to improve dietary habits.