• Journal of Korea Foundry Society
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• v.40 no.2
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• pp.34-42
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• 2020

The effects of the initial balancing pressure, filling pressure and maximum build-up pressure on the casting characteristics of the thick-wall thickness casting during the counter-pressure casting process were investigated. Water model experiment and a computer simulation were carried out to evaluate the characteristics during the filling and solidification stages in counter-pressure casting (CPC); as a reference, the low-pressure casting (LPC) process was used. The average dendrite cell size decreased with an increase in the solidification rate and maximum build-up pressure. A turbulent flow occurred during the filling stage of the LPC process, resulting in the formation of inner gas, while a lamellar flow pattern dominated during the CPC process and was more evident with an increase in the initial balancing pressure, improving the mechanical properties of the castings.

• Journal of Periodontal and Implant Science
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• v.47 no.3
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• pp.134-142
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• 2017

Purpose: This study aimed to evaluate the effects of a cetylpyridinium chloride (CPC) and tranexamic acid (TXA) mouth rinse on patients with gingivitis. Methods: This randomized, placebo-controlled, double-blind, parallel-group, clinical trial included 45 healthy adults with gingivitis, who were randomized into 2 groups. The experimental group used a 0.05% CPC and 0.05% TXA mouth rinse, and the control group used a placebo mouth rinse. The following clinical indices were assessed at baseline, at 3 weeks, and at 6 weeks: the Turesky-Quigley-Hein plaque index (QHI), the $L{\ddot{o}}e-Silness$ gingival index (GI), and bleeding on marginal probing (BOMP). The subjects used the mouth rinse during the experimental period for 20 seconds, 4-5 times daily (10 mL each time). Results: There were no significant differences in the clinical indices between the groups at baseline. In the experimental group (CPC+TXA), a statistically significant improvement was evident in the QHI, GI, and BOMP at 3 and 6 weeks. These results were similar to those observed in the control group at 3 and 6 weeks, although the change in BOMP was not statistically significant in that group. At 6 weeks, the experimental group had a significantly lower mean score for the QHI than the control group. Conclusions: This study demonstrated that a CPC and TXA mouth rinse exhibited significant antiplaque and anti-gingivitis efficacy, and had a positive effect on bleeding control when used daily for 6 weeks.

• Journal of Periodontal and Implant Science
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• v.29 no.2
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• pp.325-333
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• 1999

The antibacterial efficacy of a mouthrinse(Denta Gargle) containing CPC(cetylpyridinium chloride), NaF and UDCA(ursodeoxycholic acid), on major periodontopathogens, was in vitro examined and compared with that of Listerine by a broth dilution method. The bacteria tested were Actinobacillus actinomycetemcomitans, Bacteroides forsythus, Fusobacterium nucleatum subsp. vincentii, Prevotella intermedia, Porphyromonas gingivalis and Treponema denticola. The growth of all the bacteria were completely inhibited by a 1-min exposure to the both mouthrinses. When diluted at 1:5 or more, all bacteria analyzed but P. intermedia were not inhibited by Listerine. In contrast, Denta Gargle showed highly increased maximum inhibitory dilutions(MID) against all periodontopathogens included in this study, with MIDs ranging from 5-fold(F. nucleatum) to 160-fold dilutions(P. intermedia). The MIDs against A. actinomycetemcomitans, B. forsythus, P. gingivalis and T. denticola. were 1:40, 1:80, 1:80 and 1:80, respectively.

• Applied Chemistry for Engineering
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• v.9 no.7
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• pp.968-973
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• 1998

The critical micelle concentrations($CMC^*$) of the mixed surfactant systems of cationic surfactant cetylpyridinium chloride(CPC) and nonionic surfactant Triton X-100(TX-100) in aqueous solutions of salts(KCl and $Na_2CO_3$) and isomeric butanols(tert-butanol, iso-butanol and n-butanol) were determined by UV spectroscopy method. The various thermodynamic values in aqueous solutions of salts and isomeric butanols were compared with the values in pure water, calculated by means of the equation derived from the pseudo-phase separation model. Thermodynamic parameters($X_1$, $\beta$, ${\gamma}i$, $ai^M$, $C_i$ and ${\Delta}H_{mix}$) were found to have great effects of salts and isomeric butanols on the mixed micellization of CPC/TX-100 mixtures, and also in good agreements with the nonideal mixed micelle model. They showed all negative deviations from the ideal mixed micellar behavior.

• Journal of Periodontal and Implant Science
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• v.42 no.2
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• pp.33-38
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• 2012

Purpose: The goal of this study was to evaluate the clinical anitplaque and antigingivitis effects of a mouthrinse containing cetylpyridinium chloride (CPC), triclosan and dipotassium glycyrrhizinate (DPZ) in patients with gingivitis and mild periodontitis. Methods: Thirty-two subjects were randomized into 2 groups. The test group used a mouthrinse containing 0.05% CPC, 0.02% triclosan and 0.02% DPZ, while the control group used a placebo mouthrinse. At baseline, 2 weeks and 4 weeks, the papillary bleeding index (PBI), Turesky-Quigley-Hein plaque index (PI) and L$\ddot{o}$e-Silness gingival index (GI) were assessed. During the experimental period, the patients used the mouthrinse for 30 seconds, 4 to 5 times/day (10 mL/time) within 30 minutes after toothbrushing. Results: No adverse effects appeared in either the experimental or the control group. Regarding PBI, PI and GI values, statistical significance was detected between values at baseline and 2 weeks for both groups (P<0.05). In the experimental group, statistically significantly lower values were detected at 4 weeks compared to at 2 weeks. However, in the control group, no statistically significant difference was detected between the values at 2 weeks and 4 weeks. Additionally, the mean value after 4 weeks for the control group was slightly higher than the mean value after 2 weeks for the control group. Conclusions: This study for 4 weeks demonstrated that mouthrinses containing CPC, triclosan and DPZ may contribute to the reduction of supragingival plaque and gingivitis.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.5
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• pp.524-528
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• 2002

Green layer, Enteromorpha prolifera, is regarded as one of important materials for food processing in Korea. The acidic water-soluble polysaccharide (CPC-PS) isolated from the alga with hot water and cetylpyridium chloride was mainly constituted of rhamnose, xylose, uronic acid and sulfate. To determine the glycosyl-linkages and positions of sulfate by methylation, the CPC-PS was reduced and/or sulfates. A marked increase of glucose content in the reduced polysaccharide indicated that glucuronic acid was a major sugar in the polymer and sulfation was deduced to occur on O-3 of rhamnose and O-2 of xylose. According to the methylation analysis of the native, reduced, desulfated and reduced-desulfated polymers, CPC-PS mainly composed of 1,4- and 1,2,3-linked rhamnose 3-sulfate, 1,4-linked xylose 2-sulfate, 1,4-linked xylose and 1,4-linked glucuronic acid. Minor 1,4-linked rhamnose and 1,4,6-linked galactose residues were also detected.

• Journal of The Korean Society of Emergency Medicine
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• v.29 no.5
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• pp.519-528
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• 2018

Objective: Delayed neuropsychiatric sequelae (DNS) following carbon monoxide (CO) poisoning, which may result from a demyelinating leukoencephalopathy, is a disease with a poor prognosis. This study examined the factors affecting the long-term prognosis of DNS and the efficacy of hyperbaric oxygen therapy (HBOT) in patients with DNS. Methods: This retrospective study included 84 patients with DNS following CO poisoning from January 2013 to June 2016. HBOT was given to 24 patients. The patients were divided into an improvement group and non-improvement group based on their clinical condition on a telephone interview at intervals between 3 months and 3 years after the onset of DNS. The improvement group was defined as having Cerebral Performance Category (CPC) scores in their daily life that improve to 1 or 2 grade. Results: Of the 594 patients, DNS were found in 18.2%, and 70.2% (59 of 84) of the patients with DNS improved. The prognostic factors for the improvement of DNS were an age of 45 years or less (odds ratio [OR], 12.068; 95% confidence interval [CI], 2.393-60.858; P<0.005), CPC score of 1 or 2 group at the time of DNS onset (OR, 12.361; 95% CI, 3.161-48.330; P<0.005), and a lucid interval longer than 20 days (OR, 5.164; 95% CI, 1.393-19.141; P<0.01). HBOT was not associated with the improvement of DNS in CO poisoning (OR, 0.467; 95% CI, 0.172-1.269; P>0.1). Conclusion: Patients aged less than 45 years, low grade CPC score of 1 and 2, and lucid interval longer than 20 days are more likely to have a good prognosis. On the other hand, HBOT failed to produce a benefit for DNS patients.

• Particle and aerosol research
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• v.11 no.2
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• pp.57-61
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• 2015

Atmospheric nano-particles along the altitude is one of the main factors causing severe weather phenomena. It is a challenge to find the precise particle size distribution. One useful instrument includes a scanning mobility particle sizer (SMPS). This measures the size distribution of submicron aerosols. The SMPS consists of a condensation particle counter (CPC), differential mobility analyzer (DMA), high voltage power supplier (HVPS), and neutralizer. Due to the many components, it is difficult to install a commercial SMPS into a tethered balloon package system (Eun, 2011). In this study, we customized a SMPS for the tethered balloon package system called Hy-SMPS. It is portable, compact in structure, and evaluated by TSI SMPS using mono and poly-dispersed particles.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.04a
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• pp.201-204
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• 2003

Solubilization isotherms of 1-chlorobenzene (MCB) and 1, 2-dichlorobenzene (DCB) were investigated in ionic surfactant solutions such as sodium dodecyl sulfate (SDS), cetylpyridinium chloride (CPC), and dedecyltrimethylammonium chloride (DMAC). The solubilization extent of DCB was much higher than that of MCB because of the main driving force of solubilization Is hydrophobic interactions between chlorobenzenes and hydrophobic interior of ionic micelles and DCB is more hydrophobic than MCB. CPC showed highest solubilization capacity because of longest hydrophobic tails. Simultaneous solubilization of MCB and DCB decreased slightly the extent solubilization of both MCB and DCB because the solubilization locus in the micelles is same.

• Particle and aerosol research
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• v.14 no.2
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• pp.35-40
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• 2018

Vertical particle size distribution, total particle concentration, wind velocity, temperature and humidity measurement was performed with a drone. The drone was equipped with a wind sensor, house-made optical particle count(Hy-OPC), condensation particle counter(Hy-CPC), GPS, Temperature, Relative Humidity, Pressure and communication system. Base on the wind velocity and the particle size vertical distribution measurement with drone, the particle mass flux was calculated. The vertical particle distribution showed that the particle number concentration was very strongly correlated with the relative humidity.