Engineering, South Korea
Engineering, South Korea

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Hong I.K.,Dankook UniversityGyeonggi | Kim S.I.,Dankook UniversityGyeonggi | Park B.R.,Dankook UniversityGyeonggi | Choi J.,Dankook UniversityGyeonggi | Lee S.B.,Dankook UniversityGyeonggi
Applied Chemistry for Engineering | Year: 2016

Emulsification is a fundamental process of cosmetics manufacture which produces stabilized emulsion by dispersing the liquid from the one side to the other by adding an emulsifier in an immiscible liquid. Various types of emulsifiers can produce various cosmetics. In this study, we evaluated the stability of emulsifier by measuring variations in the viscosity, particle size and particle size distribution. HLB values of nonionic emulsifiers which are used in this paper are 12.9, 12.9, 12.6 and 12.5 for EMU-01, EMU-02, EMU-03 and EMU-04, respectively. All types of emulsions showed an increase in the particle size and a decrease in the viscosity with the time. Also they showed a decrease in the particle size and an increase in the viscosity with respect to increasing the stirring speed. However, the stability of emulsions up to 56 days was secured by observing the non-separation of emulsions. In addition, the viscosity of the emulsions was measured in the order of EMU-01 > EMU-02 > EMU-03 > EMU-04 while the size of particles was measured in the order of EMU-01 ≈ EMU-02 > EMU-03 ≈ EMU-04. This indicates that our emulsion can be potentially used for preparing a cosmetic facial cream. © 2016, Korean Society of Industrial Engineering Chemistry. All rights reserved.


Kim S.H.,Kongju National University | Kim W.K.,Dankook UniversityGyeonggi | Kang M.-H.,Hannam University
Nutrition Research and Practice | Year: 2016

BACKGROUND/OBJECTIVES: A healthy diet has been reported to be associated with physical development, cognition and academic performance, and personality during adolescence. This study was performed to investigate the relationships among milk consumption and academic performance, learning motivation and strategies, and personality among Korean adolescents. SUBJECTS/METHODS: The study was divided into two parts. The first part was a survey on the relationship between milk consumption and academic performance, in which intakes of milk and milk products and academic scores were examined in percentiles among 630 middle and high school students residing in small and medium-sized cities in 2009. The second part was a survey on the relationships between milk consumption and learning motivation and strategy as well as personality, in which milk consumption habits were collected and Learning Motivation and Strategy Test (L-MOST) for adolescents and Total Personality Inventory for Adolescents (TPI-A) were conducted in 262 high school students in 2011. RESULTS: In the 2009 survey, milk and milk product intakes of subjects were divided into a low intake group (LM: ≤ 60.2 g/day), medium intake group (MM: 60.3-150.9 g/day), and high intake group (HM: ≥ 151.0 g/day). Academic performance of each group was expressed as a percentile, and performance in Korean, social science, and mathematics was significantly higher in the HM group (P < 0.05). In the 2011 survey, the group with a higher frequency of everyday milk consumption showed significantly higher “learning strategy total,” “testing technique,” and “resources management technique” scores (P < 0.05) in all subjects. However, when subjects were divided by gender, milk intake frequency, learning strategy total, class participation technique, and testing technique showed significantly positive correlations (P < 0.05) in boys, whereas no correlation was observed in girls. Correlations between milk intake frequency and each item of the personality test were only detected in boys, and milk intake frequency showed positive correlations with “total agreeability”, “organization”, “responsibility”, “conscientiousness”, and “intellectual curiosity” (P < 0.05). CONCLUSION: Intakes of milk and milk products were correlated with academic performance (Korean, social science, and mathematics) in Korean adolescents. In male high school students, particularly, higher milk intake frequency was positively correlated with learning motivation and strategy as well as some items of the personality inventory. © 2016 The Korean Nutrition Society and the Korean Society of Community Nutrition.


Kim H.,Kimpo UniversityGyeonggi | Lee S.B.,Dankook UniversityGyeonggi
Applied Chemistry for Engineering | Year: 2015

A pretreatment process of cellulose decomposition to a monosaccharide plays an important role in the cellulosic ethanol production using the lignocellulosic biomass. In this study, a cellulosic ethanol was produced by using acidic hydrolysis and enzymatic saccharification process from the lignocellulosic biomass such as rice straw, sawdust, copying paper and newspaper. Three different pretreatment processes were compared; the acidic hydrolysis (100 ℃, 1 h) using 10~30 wt% of sulfuric acid, the enzymatic saccharification (30 min) using celluclast (55 ℃, pH = 5.0), AMG (60 ℃, pH = 4.5), and spirizyme (60 ℃, pH = 4.2) and also the hybrid process (enzymatic saccharification after acidic hydrolysis). The yield of cellulosic ethanol conversion with those pretreatment processes were obtained as the following order: hybrid process > acidic hydrolysis > enzymatic saccharification. The optimum fermentation time was proven to be two days in this work. The yield of cellulosic ethanol conversion using celluclast after the acidic hydrolysis with 20 wt% sulfuric acid were obtained as the following order: sawdust > rice straw > copying paper > newspaper when conducting enzymatic saccharification. © 2015, Korean Society of Industrial Engineering Chemistry. All rights reserved.


Hong I.K.,Dankook UniversityGyeonggi | Jeon G.S.,Dankook UniversityGyeonggi | Lee S.B.,Dankook UniversityGyeonggi
Applied Chemistry for Engineering | Year: 2015

The physical properties, such as the heat resistance and thermal durability of the temperature difference fatigue resistance should be excellent when preparing an epoxy type resin for a neon transformer housing. In this study, 50 wt% of SiO2 and silica were selected as a reinforcement and diluent filler for epoxy type resins, respectively. Thermal conductivity and thermal stability were measured as the mixing ratio varied upon the particle sizes. The optimal amount of the mixed silica was 50 wt%. Thermal stability was improved with increasing the amount of larger silica particles. The optimal mixing ratio of differently sized silica particles was 28/3: 14/18: 8/10 mesh = 1: 1: 1. From these results, it is thought that neon transformer is producible which has excellent thermal durability. © 2015, Korean Society of Industrial Engineering Chemistry. All rights reserved.


Kim B.Y.,Dankook UniversityGyeonggi | Lee C.-T.,Dankook UniversityGyeonggi
Applied Chemistry for Engineering | Year: 2015

Extraction of phytoncide oil from korea pine cone waste without damaging the pine cone tree itself was investigated using a steam distillation method. Also various components in the extracted phytoncide oil were separated using a column chromatography method. The extraction of phytoncide oil was effectively proceeded, and the maximum production yield of phytoncide oil could be obtained under 100 °C of distillation temperature and within 30 minute of distillation time. According to chemical analysis, it was found that the phytoncide oil from korea pine cone waste was consisted of more than 12 components such as α-pinene, β-pinene, D-limonene, as main components. In addition, the aqueous hydrogel containing other components such as verbenone, α-terpinieol, fenchol, different from components of phytoncide oil itself could be obtained through the steam distillation. © 2014 The Korean Society of Industrial and Engineering Chemistry. All rights reserved.


Lee S.B.,Kimpo CollegeGyeonggi | Kim H.,Dankook UniversityGyeonggi
Applied Chemistry for Engineering | Year: 2014

The acid hydrolysis and enzymatic saccharification were carried out for the production of cellulosic ethanol. The possibility of bio-energy production from tangerine peel and apple and watermelon rind was evaluated by determining the optimum production condition. The optimum conditions for the production of cellulosic ethanol from fruit peel were as follows: the sulfuric acid concentration and reaction time of acid hydrolysis for the ethanol production from an apple rind were 20 wt% and 90 min, respectively. The concentration of sulfuric acid for tangerine peel and a watermelon rind at the hydrolysis time of 60 min were 15 wt% and 10 wt%, respectively. A viscozyme was proven as the best conversion for the ethanol production when using enzymatic saccharification from fruit peels. The optimum enzymatic saccharification time for tangerine peel and apple and watermelon rind were 60, 180, and 120 min, respectively. © 2014 The Korean Society of Industrial and Engineering Chemistry. All rights reserved.


Lee C.-T.,Dankook UniversityGyeonggi
Applied Chemistry for Engineering | Year: 2015

A new concept of an inorganic foaming process at low temperature was demonstrated for the production of inorganic thermal insulating materials with the properties of flexible light-weight, the advantages of organic-based thermal insulation material. The foaming process was proceeded by establishing a skeleton of the foam body by using inorganic fibrous sepiolite and aluminum silicate. A cavity was formed by the expansion of fibrous skeleton body, by the gas which was generated from foaming agent at low temperature. Then the multi-vesicular expanded perlite with low thermal conductivity was filled into the cavity in a skeleton of the foam body. Finally through these overall process, a new inorganic foamed body could be obtained at low temperature without the hot melting of inorganic materials. In order to achieve this object, various preparations such as fibrous sepiolite fibrillation process, heat treatment process of the fibrous slurry were needed, and the optimal compositional condition of slurry was required. The foam body produced showed the properties of flexible light-weight thermal insulation materials such as bulk density, yield strength, flexural strength, and high heat resistance. © 2015, Korean Society of Industrial Engineering Chemistry. All rights reserved.


Hong I.K.,Dankook UniversityGyeonggi | Lee C.G.,Dankook UniversityGyeonggi | Lee S.B.,Dankook UniversityGyeonggi
Applied Chemistry for Engineering | Year: 2015

Thermoplastic road markings are one of the most widely used road markings in the world. However, the durability of domestic road markings is relatively shorter than that of the global average of, approximately, three years. To overcome it, the conventional thermoplastic road markings were prepared by adding polyolefin and oxidized PE wax to conventional petroleum resin. In addition, the melting viscosity was designed below 500 cP at 220 ℃ as well as the optimum viscosity for spray painting, and embedding ratio of glass beads were controlled about 50∼60% by spraying in an interval of 1 second. Also the glass bead adhesive ratio was improved by reducing the amount of CaCO3 below 40 wt%. The retroreflectivity was tested under four different conditions to evaluate the abrasion resistance of thermoplastic road markings. The retroreflectivity coefficient satisfied the international standard (150 mcd⋅m-2⋅lux-1) in this study, and TPRM-7 was determined as an optimal ratio. © Korean Society of Industrial Engineering Chemistry. All rights reserved.


Lee S.B.,Dankook UniversityGyeonggi | Jeon G.S.,Dankook UniversityGyeonggi | Jung R.Y.,SeoAn ChemTech Co. | Hong I.K.,Dankook UniversityGyeonggi
Applied Chemistry for Engineering | Year: 2016

When copper alloy is used in etching process for the production of lead frame, the high concentration of heavy metals, such as iron, nickel and zinc may be included in the etching waste. Those etching waste is classified as a specified one. Therefore a customized design was designed for the purification process of the lead frame etching waste liquid containing high concentrations of heavy metals for the production of an electroplating copper(II) oxide. Since the lead frame etching waste solution contains highly concentrated heavy metal species, an ion exchange method is difficult to remove all heavy metals. In this study, a copper(I) chloride was manufactured by using water solubility difference related to the reduction-oxidation method followed by the reunion of copper(II) chloride using sodium sulfate as an oxidant. The hydrazine was chosen as a reducing agent. The optimum added amount was 1.4 mol per 1.0 mol of copper. In the case of removal of heavy metals by using the combination of reduction-oxidation and ion exchange resin methods, 4.3 ppm of Fe3+, 2.4 ppm of Ni2+ and 0.78 ppm of Zn2+ can be reused as raw materials for electroplating copper(II) oxide when repeated three times. © 2016, The Korean Society of Industrial and Engineering Chemistry. All Rights Reserved.


Lee C.-T.,Dankook UniversityGyeonggi
Applied Chemistry for Engineering | Year: 2016

The purpose of this research was to develop a flat panel display device’s glass etchant which can replace hydrofluoric acid. The glass etchant was composed of 18~19% wt% of ammonium hydrogen fluoride, 24~25 wt% of sulfuric acid, 45~46 wt% of water, 4~5 wt% of sulfate and 7~8 wt% of fluoro-silicate. By replenishing the etchant which has the amount of 5% of initial solution’s mass, it was possible to reuse the etchant continuously. The developed etchant showed 5µm/min of etching rate at 30 °C. The reusable etchant, with replenishing 5% of initial etchant mass showed the stable etching rate, which has the deviation of less than 0.1 µm/min etching rate. The glass surface of flat panel display device created from our etching process was in good condition with any defects such as pin hole and dimple. © 2016, The Korean Society of Industrial and Engineering Chemistry. All Rights Reserved.

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