• Korean Chemical Engineering Research
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• v.43 no.1
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• pp.170-175
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• 2005

In this study, mercury was removed by $TiO_2$ using fluorescent light and sunlight, instead of UV lamps. A reactor was specially designed to increase the $TiO_2's$ exposure to the light source and to make the rotational speed constant. The contacting surface area between mercury and adsorbents was increased by packing the adsorption bed with mixture of $TiO_2$ and glass beads. The mercury removal efficiency was more than 99% under all light sources tested in this study. The mercury removal efficiency was more than 99% under the fluorescent light or sunlight which is harmless and cheap or free.

• Journal of the East Asian Society of Dietary Life
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• v.12 no.3
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• pp.210-217
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• 2002

This study was carried out to investigate the possibility of improving the texture and the flavor of Dasik made of the Omija extract, various sugars and rice powder. Sensory quality and mechanical characteristics of Dasik were compared. The moisture content of the Croup of tile Dasik added with Omija extract was higher than that with non-Omija extract The Omija Dasik containing molasses showed the highest value (23.5%) in moisture content. In sensory quality, Omija Dasik containing honey and symp showed the highest score in overall acceptability (6.2 and 6.0, respectively). The Rice Dasik containing syrup showed the highest values in lightness (L) and yellowness (b) in color. The Omija Dasik containing syrup showed the highest values in redness (a) in color. The Dasik added with honey and syrup were lower in hardness, but higher in cohesiveness, springiness, gumminess and brittleness of textural characteristics. When sensory quality and mechanical characteristics of the Dasik were compared with, the gumminess and brittleness in mechanical characteristics were positively correlated with the appearance and the taste acceptability in sensory quality (p<.01, p<.05). The springiness was negatively correlated with the tooth packing in sensory quality (p<.001). The Omija Dasik was more desirable in flavor, taste and overall acceptability, especially those added with honey and syrup. From the above results, the honey might be replaced by the less expensive syrup, when making the Omija Dasik.

• Bulletin of the Korean Chemical Society
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• v.30 no.5
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• pp.1021-1025
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• 2009

A novel supramolecular network containing binuclear copper unit $[Cu(phen)_{2}({\mu}-ID\;A)Cu(phen){\cdot}(NO_{3})](NO_{3}){\cdot}4(H_{2}O)$ (1) was synthesized through the self-assembly of iminodiacetic acid ($H_2IDA$) and 1,10-phenanthroline (phen) in the condition of pH = 6. It has been characterized by the infrared (IR) spectroscopy, elemental analysis, single crystal X-ray diffraction, and thermogravimetric analysis (TGA). 1 shows a 2-D supramolecular structure assembled through strong and unique $\pi-\pi$ packing interactions. Density functional theory (DFT) calculations show that theoretical optimized structures can well reproduce the experimental structure. The TGA and powder X-ray diffraction (PXRD) curves indicate that the complex 1 can maintain the structural integrity even at the loss of free water molecules. The magnetic property is also reported in this paper.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.17 no.2
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• pp.110-113
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• 2008

Embedded capacitor technology is one of the effective packing technologies for further miniaturization and higher performance of electric packaging system. In this paper, the embedded capacitors were simulated and fabricated in 8-layered printed circuit board employing standard PCB processes. The composites of barium titanante($BaTiO_3$) powder and epoxy resin were employed for the dielectric materials in embedded capacitors. Theoretical considerations regarding the embedded capacitors have been paid to understand the frequency dependent impedance behavior. Frequency dependent impedance of simulated and fabricated embedded capacitors was investigated. Fabricated embedded capacitors have lower self resonance frequency values than that of the simulated embedded capacitors due to the increased parasitic inductance values. Frequency dependent capacitances of fabricated embedded capacitors were well matched with those of simulated embedded capacitors from the 100MHz to 10GHz range. Quality factor of 20 was observed and simulated at 2GHz range in the 10 pF embedded capacitors. Temperature dependent capacitance of fabricated embedded capacitors was presented.

• Bulletin of the Korean Chemical Society
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• v.34 no.2
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• pp.374-378
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• 2013

Two novel binuclear metal-organic coordination complexes [$Cd_2(Hdpa)_4(bpy)_2$] (1), [$Dy_2(dpa)_2(bpy)_2(NO_3)_2-(H_2O)_2$](bpy) (2) (where $H_2dpa$ = biphenyl-2,2'-dicarboxylic acid, bpy = 2,2'-bipyridine) have been synthesized under hydrothermal conditions and characterized by single crystal X-ray diffraction, spectral method (IR), elemental analysis (EA), powder X-ray diffraction (XRD), electronic spectra (UV-vis), fluorescent in the solid state and thermogravimetric analysis (TGA). Complexes 1-2 crystallizes isomorphously in the Triclinic space group P-1. The ${\pi}-{\pi}$ stacking interactions and hydrogen-bonds play a vital role in determining the crystal packing and construction of the extended 3-D supramolecular network.

• Korean journal of food and cookery science
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• v.19 no.3
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• pp.280-285
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• 2003

This study was carried out to investigate the effects of the addition of sweeteners to Sesame Dasiks. Sesame Dasiks were prepared by adding various sweeteners to sesame seeds powder, at 40, 50, 60 and 70%, and their quality characteristics were measured. In the chewiness and hardness analyses of Sesame Dasiks, the 50% group (the same ratio and mixture of honey and rice jelly) eave the highest results. For the sweetness, taste and overall acceptability of the Sesame Dasiks, the 50% group was also the better The texture profile analyses found the optimal chewiness and hardness of the Sesame Dasik to be 0.28∼0.30 and 27.22∼27.44, respectively.

• Korean Journal of Materials Research
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• v.29 no.7
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• pp.425-431
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• 2019

Generally, ceramic tiles for building construction are manufactured by dry forming process using granular powders prepared by spray drying process after mixing and grinding of mineral raw materials. In recent years, as the demand for large ceramic tiles with natural texture has increased, the development of granule powders with high packing ratio and excellent flowability has become more important. In this study, ceramic tile granule powders are coated with hydrophobically treated silica nanoparticles. The effects of hydrophobic silica coating on the flowability of granule powders and the strength of the green body are investigated in detail. Silica nanoparticles are hydrophobically treated with GPTMS(3-glycidoxypropyl trimethoxy silane), which is an epoxy-based silane coupling agent. As the coating concentration increases, the angle of repose and the compressibility decrease. The tap density and flowability index increase after silica coating treatment. These results indicate that hydrophobic treatment can improve the flowability of the granular powder, and prevent cracking of green body at high pressure molding.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.26 no.2
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• pp.225-236
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• 2016

Objectives: Nanomaterials have been used in various fields. As use of nanoproducts is increasing, workers dealing with nanomaterials are also gradually increasing. Exposure assessments for nanomaterials have been carried out for protection of worker's health in workplace. Exposure studies were mainly focused on manufacturing processes, but these studies on after-treatment processes such as refinement, weighing, and packing were insufficient. So, we investigated exposure characteristics of particles during after-treatment processes of $Al_2O_3$ fibers and Ni powders. Methods: Mass-production of Ni powder process was carried out in enclosed capture-type canopy hood. In a developing stage, $Al_2O_3$ was handled with a local ventilation unit. Exposure characteristics of particles were investigated for $Al_2O_3$ fiber and Ni powder processes during the periods of 10:00 to 16:00, 20 May 2014 and 13:00 to 16:00, 21 May 2014, respectively. Three real-time aerosol instruments were utilized in exposure assessment. A scanning mobility particle sizer(SMPS, nanoscan, model 3910, TSI) and an optical particle counter(OPC, portable aerosol spectrometer, model 1.109, Grimm) were used to determine the particle size distribution in the size range of 10-420 nm and $0.25-32{\mu}m$, respectively. In addition, a nanoparticle aerosol monitor(NAM, model 9000, TSI) was used to measure lung-deposited nanoparticle surface area. Membrane filters(isopore membrane filter, pore size of 100 nm) were also used for air sampling for the FE-SEM(model S-5000H, Hitachi) analysis using a personal sampling pump(model GilAir Plus by 2.5 L/min, Gilian). Conclusions: For Ni powder after-treatment process, only 27% increase in particle concentration was found during the process. However, for $Al_2O_3$ fiber after-treatment process, significant exposure(1.56-3.34 times) was observed during the process.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.2
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• pp.222-227
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• 2007

This study was carried out to investigate the influence of feeding eosungcho (Houttuynia cordata Thunb) powder on the meat quality of porks at chilled storage. Experimental groups were divided into control group (0%, C), 5% (T1) and 10% (T2) eosungcho powder feeding group, and then administered for 12 weeks. The results of sensory evaluation for softening value and scorched smell showed the highest preference in T1 group. Overall acceptability was also the highest in T1 group than the others. Physicochemical components were analyzed for pork loins that were stored at $4^{\circ}C$ for 23 days after vacuum packing. The moisture contents of pork loins were higher in T1 group than the others. Crude lipid contents were lower in T1 and T2 groups than the control group. The pH values were not significantly different in experimental groups during storage days. The Hunt L and a values increased significantly according to storage days. The Hunt b value was increased for the initial storage days but it did not change after 9 storage days. The Warmer-Bratzler share force of all experimental groups were greatly decreased between 2 and 9 storage days and then little exchanged afterwards.

• Proceedings of the KAIS Fall Conference
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• 2010.11b
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• pp.1017-1020
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• 2010

최근 국산 농산물의 수요급증과 더불어 소비자들은 안전한 제품의 요구가 높아지고 있다. 이러한 요구에 맞는 제품 개발의 일환으로 미생물 제어가 된 고춧가루 포장제품의 품질향상을 위한 천연항균 물질 소재를 탐색하여 제품개발에 응용하였다. 천연물과 한방재료 중 고춧가루 제품에 적합한 소재를 스크리닝하여 항균물질을 탐색하였으며 고춧가루 제품 패킹에 응용하였다. 천연물 항균제의 개발 원칙은 산취 등 이취가 없어야 하며, 제품에 응용할 수 있는 용해성이나 믹싱의 효과를 높이도록 공정을 최적화 하였다. 또한 최종 천연물 항균제의 형태는 분말 형태로 개발하였다. 천연물에 대한 항균활성은 paper disk test를 통하여 비교하였으며, 항균력이 가장 우수한 소재는 황금추출물이었다. 또한 이들 추출물과 비타민 $B_1$ 인산염의 영향을 함께 비교하였다. 이 천연물 소재 추출물로 개발한 항균물질에 대한 효과는 일반세균, 대장균 검사를 실시하였다. 제품의 안정성 확보 및 유통기한 연장 가능성을 실험한 결과, 일반세균은 $1.0{\times}10^5$cfu/g, 대장균군은 $1.0{\times}10^2$cfu/g, 대장균은 불검출 되었다. 이들 추출물의 항균제 개발과 더불어 다양한 식품에 천연물 항균제로서의 적용 가능성을 모색하고자 하며, 안전한 천연 항균제 개발에 대한 기초 자료를 제공하는 기초 연구를 하고자 하였다.