• Carbon letters
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• v.1 no.3_4
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• pp.170-177
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• 2001

Lithium intercalated carbon (LIC) are basically employed as an anode for currently commercialized lithium secondary batteries. However, there are still strong interests in modifying carbon surface of active materials of the anode because the amount of irreversible capacity, charge-discharge capacity and high rate capability are largely determined by the surface conditions of the carbon. In this study, the carbonaceous materials were coated with tin oxide and copper by fluidized-bed chemical vapor deposition (CVD) method and their coating effects on electrochemical characteristics were investigated. The electrode which coated with tin oxides gave the higher capacity than that of raw material. Their capacity decreased with the progress of cycling possibly due to severe volume changes. However, the cyclability was improved by coating with copper on the surface of the tin oxides coated carbonaceous materials, which plays an important role as an inactive matrix buffering volume changes. An impedance on passivation film was decreased as tin oxides contents and it resulted in the higher capacity.

• Journal of Korean society of Dental Hygiene
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• v.20 no.3
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• pp.387-397
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• 2020

Objectives: This study aimed to evaluate the inhibitory effects of probiotics containing Lactobacillus reuteri on Streptococcus mutans and Aggregatibacter actinomycetemcomitans. In addition, the degree of biofilm formation, initial acidity, buffering ability, and acid production performance were measured to confirm the dental caries-inducing ability. Methods: S. mutans (KCTC3065) and A. actinomycetemcomitans (KCTC2581) were used as experimental strains. The number of viable cells, degree of biofilm formation, initial pH, buffering capacity, and production performance were measured for comparing L. reuteri-containing probiotics and Bulgaris. Results: The viability of S. mutans in the groups was reduced in the following order: Bulgaris, probiotics, control. The degree of biofilm formation was significantly higher at 0% and gradually reduced at different concentrations (p<0.01). At 2.5%, the absorbance of the probiotics and Bulgaris groups differed significantly (p<0.01). The acid formation ability differed significantly based on the performance of S. mutans in each product (p<0.05). The absorbance of the probiotics group was significantly lower than that of the Bulgaris group (p<0.01). Conclusions: This study suggests that the use of L. reuteri-containing probiotics as an adjuvant for the prevention and decreasing of oral diseases may reduce their incidence, which can be considered one of the benefits of using probiotics.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.29 no.11
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• pp.53-58
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• 2015

Systemic heating and cooling air conditioning systems are popular in various industrial fields and even home. Recently, the rate of supply of this kind of multi-heat pump has been increased under ESCO financing supporting system. Generally the heat pumping system has a structural simplicity and easy installation benefits. and has good running efficiency under normal designed condition. But under extreme climate condition (over $+30^{\circ}C$, under $-10^{\circ}C$), this system exposes abnormal power consumption. It causes high progressive electric power rates and resultant peak power capacity of power plant. In this paper, a novel system concept of buffering refrigerant accumulator and constant pressure control system to relieve peak power load is proposed and this system's utility is verified with an prototype experimental system.

• Journal of Korean society of Dental Hygiene
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• v.3 no.2
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• pp.197-208
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• 2003

This study was implemented for 84 students of dental hygiene to show the correlation between dental caries experience and improved caries activity test. Dental caries experience for the sample groups was examined and stimulative saliva secreted for 5 minutes was collected into the tube to check saliva secretion rate. Dentocult LB test was executed to observe Lactobacilli colonies after 96 hour cultivation of culture slides moistened with stimulative saliva. Dentocult SM test(screening strip, site strip) was done to measure SM colonies distribution after 48 hour cultivation of culture strips applied with collected saliva and dental plaque respectively, and salivary buffering capacity was checked by means of Dentobuff strip kit. Following conclusions are obtained after examining the relation between Dentocult LB, Dentocult SM, Dentobuff strip test results and DMFT index, salivary secretion rate. 1. Showed no significant difference between Dentocult LB test results and DMFT index, salivary secretion rate. 2. Showed no significant difference between Dentocult SM(screening strip) test results and DMFT index, salivary secretion rate. 3. Showed significant difference between Dentocult SM(site strip) test results and DMFT index(pE0.05), but showed no significant difference between Dentocult SM(site strip) test results and salivary secretion rate. 4. Showed no significant difference between Dentobuff strip test results and DMFT index, but showed a very wide difference between Dentobuff strip test results and salivary secretion rate(pE0.01).

• Journal of Korean society of Dental Hygiene
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• v.20 no.5
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• pp.753-762
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• 2020

Objectives: This study was aimed at evaluating the effects of changes in the oral environment of the elderly in long-term care facilities after the intake of Weissella cibaria. Methods: The test group ingested the W. cibaria strain Chonnam Medical University (CMU), and the control group ingested the control food. Of all randomized trial subjects, 62 were analyzed (32 in the experimental group and 30 in the control group). In this 8-week demographic study, we evaluated self-perceived halitosis, changes in halitosis, sensory test results, tongue plaque index scores, saliva buffering capacity, and the salivary flow rate. Results: The W. cibaria CMU intake in the elderly in long-term care facilities during the experimental period did not demonstrate statistically significant changes in the salivary flow rate. However, self-perceived halitosis, organoleptic test results, tongue plaque index scores, and salivary buffering capacity demonstrated statistically significant differences between the experimental and control groups. These findings partially confirmed the beneficial effects of the W. cibaria CMU on the oral environment in the elderly. Conclusions: Research results on the role of probiotics in the oral cavity should be summarized, and utilization plans should be sought to obtain a clearer understanding of the clinical efficacy and related factors. The value of probiotic use may be high in improving the oral health of people by enabling treatment and prevention.

• Korean Journal of Microbiology
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• v.38 no.3
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• pp.168-172
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• 2002

Budding yeasts maintain an effective system to regulate intracellular pH in response to environmental pH fluctuation. In a previous study we reported that SHC1 plays a role in cell growth at alkaline condition, not at acid pH. We constructed a null mutant deleted an entire open reading frame for SHC1. To test whether the retardation in cell growth was caused by the absence of intracellular pH buffering capacity, we measured intracellular pH with a pH-sensitive fluorescent dye, C.SNARE. The intracellular pH of the mutant cell was much higher than that of wild-type cells, indicating that the mutant cells lack some types of buffering capacity. We also investigated the level of $Na^＋ and K^＋$ content with atomic mass spectroscopy after alkali shock. Wild-type cell showed a higher level of intracellular K^＋$ content, whereas there was no difference in $Na^＋$ level. The result suggested that K^＋$ is more important in the regulation of intracellular pH in yeasts.

• Journal of the Korean Recycled Construction Resources Institute
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• v.12 no.2
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• pp.214-221
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• 2024

The present study concerns the resistance of calcium aluminate cement (CAC) to steel corrosion. The corrosion behavior of steel, chloride binding/buffering and chloride transport were evaluated in order to predict the risk of steel corrosion. The CAC mortar exhibited no corrosion on steel, irrespective of the curing temperature and CAC types, whereas ordinary Portland cement (OPC) showed a severe corrosion on the steel surface. The chloride binding capacity of CAC found to be was lower than that of OPC, yet buffering capacity against pH decrease was found to be significantly higher in the CAC paste. Furthermore, chloride ingress at all depths was found to be reduced in CAC, thereby reducing the risk of corrosion.

• Journal of Technologic Dentistry
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• v.10 no.1
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• pp.151-157
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• 1988

For the detection of the active cariogenic factors contributing to caries development, some practical methods such as the Snyder test, estimation of salivary flow rate and salivary buffering capacity test were evaluated statistically by comparing DMFT and DMFS indexes. Total 122 children (62 male and 60 female ; 64 rural and 58 urban) were selected ramdomly from the 6th grade of the primary school and their salivary cariogenic factors were analysed and evaluated. Among the total 122 children, 78.7% was positive in the snyder test in which the marked, moderate and slight caries activities were 29.5%, 30.3% and 18.9%, respectively. In the Snyder test, 74.45% was positive in urban children while 84.48% was positive in rural children. DMFT and DMFS indexes were markedly lower in negative group than positive group of the Snyder test (p<0.01). The mean and standard deviation of stimulated salivary flow rate was 6.97$\pm$2.57 in male and 6.34$\pm$2.54 in female but no significant difference was observed in sexuality. The stimulated salivary flow rate of urban children was slightly higher that of rural but there was no significant difference between them. However, the group that showed below average in the stimulated salivary flow rate was markedly higher in DMFI and DMFT indexes than the group of above average. The mean and standard deviation of stimulated salivary buffering capacity was 7.65$\pm$2.19 in male and 6.80$\pm$1.67 in female. This difference was significant statistically(p<0.05). Stimulated salivary buffering capacity of urban children was higher than that of rural. Increases in stimulated salivary flow rate and buffering capacity had reduced the onset of dental caries of 14-year-old permanent tooth.

• Journal of the korean academy of Pediatric Dentistry
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• v.34 no.3
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• pp.370-382
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• 2007

The aims of this study were to compare the status of dental caries between mental retarded persons(MR) and normal persons and investigated the association among dental caries and oral factors(plaque index, S. mutans, Lactobacillus, buffering capacity, salivary total IgA and anti-S. mutans IgA titers). DMFS index and plaque index were significantly greater in the MR person group than in the normal person group. The concentration of S. mutans-specific IgA was significantly greater in the normal person group than in the MR person group, but that of salivary total IgA was not show the significant difference. Salivary buffering capacity was significantly greater in the normal person group than in the MR person group, but the counts of salivary S. mutans and Lactobacillus were not significantly different. By age group(I: 9-11Y, II: 12-14Y, III: 15-18Y), DMFS index and plaque index were significantly greater in the MR person group than in the normal person group at III. The S. mutans counts and Lactobacillus counts were significantly greater in the normal person group than in the MR person group at I, but those were contrary at II, III. There was a high correlation among caries index and buffering capacity, level of S. mutans and Lactobacillus, plaque index at III.

• Journal of the korean academy of Pediatric Dentistry
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• v.27 no.1
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• pp.32-39
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• 2000

The purpose of this study was to assess the cariogenic potential of five infant formulas in vitro. as compared with 10% sucrose solution and whole bovine milk. Buffering capacities were determined by the amount of 0.1 N lactic acid consumed to titrate the 50ml specimen solutions to pH 4.0. The pH of the specimen solution inoculated by Streptococcus mutans was measured by pH meter and the surface microhardness of primary tooth enamel immersed in the specimen solution was measured by the microhardness tester, before and after 48 hours incubation. Also, the solubility of calcium from synthetic hydroxyapatite was evaluated by atomic absorption spectrophotometer The buffering capacity of infant formulas was higher than that of sucrose solution and lower than that of milk, and there were significant differences among infant formulas(P<0.01). The average pH of infant formulas after 48 hours incubation was lower than that of sucrose solution and milk, and there was significant difference between infant formulas and milk(P<0.05). There were no signifiant differences among oops in the microhardness change of primary tooth enamel and in the amount of dissolved calcium ion from synthetic hydroxyapatite after incubation with Streptococcus mutans. In conclusion, infant formulas seemed to fulfill the basic requirments to cause dental caries in primary teeth, and there were significant differences of cariogenic potential among infant formulas. Cooperative efforts of dentistry and manufacturers to reduce the cariogenic potential of infant formulas would be necessary to prevent the early childhood caries in children.