• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.124.1-124.1
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• 2015

$TiO_2$는 화학적으로 안정하며, 인체에 무해하고, 살균특성 및 각종 유기물에 효과적인 분해력, 안정성 및 내구성들의 장점으로 인해 널리 사용되는 광촉매제로 알려져 있다. 최근 $TiO_2$는 유리에 접촉되는 물방울의 표면장력을 크게 하여 접촉각을 10도 이하로 유지시켜줌으로써 비가 오거나 청소를 위해 살수를 할 때 유리면에 얇은 수막을 형성시켜 광촉매 기능으로 분해된 유기질의 오염물질 및 유리표면과의 결합력이 낮아진 무기질의 오염원을 쉽게 제거해 주는 특성들로 인해 오염방지 코팅제로 많이 활용되고 있다. 그러나, $TiO_2$는 빛이 조사될 경우에만 친수특성을 나타낸다는 단점들이 있어 본 연구에서는 $TiO_2$에 $SnO_2$를 혼합한 박막을 증착하여 신뢰성을 향상시키고자 하였다. 또한 기존 $TiO_2$ 코팅막들이 주로 spray 또는 blade 방식으로 코팅되어 코팅된 막이 낮은 균일성과 내구성을 가지므로 본 연구에서는 RF-Magnetron Sputtering 방법을 이용하여 유리 기판위에 $(TiO_2)50(SnO_2)50$ 박막을 증착하였다. 제작된 박막은 유리에 적용될 경우를 감안해 광학적 특성을 분석하기 위해 Uv-vis Spectrometer 장비를 이용하여 투과율을 분석하였으며, $SnO_2$ 혼합에 따른 구조적 특성으로 주사전자현미경(Scanning Electric Microscope, SEM)을 통하여 박막의 결정상을 분석하였으며, 주사탐침현미경(Atomic Force Microscope, AFM)을 사용하여 표면 거칠기를 관찰하였다. 또한 광촉매 특성을 통한 친수성을 알아보기 위해 UV 램프를 사용한 후 접촉각을 측정하였다.

• Korean Chemical Engineering Research
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• v.48 no.3
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• pp.350-354
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• 2010

In natural world various inorganic crystals are grown with controlled shape and size in hybrid forms with organics. Such natural processes have been attempted much to mimick artificially. One of the example is calcium carbonate which has been examined a lot in the field of biomineralization. In this study, we utilize well-organized surface of polydiacetylene(PDA) films as the crystal-growing template. We devised a novel mini-arrayer device that transfers PDA films at air/water interfaces of each array well and deposit them to hydrophobized glass substrates. This technical improvement will contribute to facilitate better understandings of biomineralization mechanism.

• Journal of Adhesion and Interface
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• v.20 no.4
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• pp.146-154
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• 2019

In this study, alkoxysilane-functionalized amphiphilic polymer (AFAP), which have hydrophilic segment and hydrophobic segment functionalized by alkoxysilane group at the same backbone, was synthesized and used as a dispersant and control agent for reaction rate in the preparation of colloidally stable organic-inorganic (O-I) hybrid sols. After reaction with fluorosilane compounds, fluorinated O-I hybrid sols were prepared and coated onto glass substrate to form hydrophobic O-I hybrid coating films through low-temperature curing process. Surface hardness and hydrophobicity of cured coating films were varied with type of solvent and composition of AFAP and fluorinated alkoxysilane compounds. At appropriate solvent and composition of fluorinated alkoxysilane compounds, O-I hybrid coating film having high transparency and surface hardness could be prepared, which could be applicable to cover window of solar cell and displays.

• Food Science and Preservation
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• v.12 no.2
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• pp.156-160
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• 2005

To obtain basic data utilizing chestnuts as a raw food material, proximate analysis was conducted. Chemical component of chestnut flesh were $63.60\%$ moisture, $118\%$ ash, $3.02\%$ crude protein, $0.615\%$ crude fat, $1.21\%$ crude fiber, and $30.37\%$ nitrogen free extract, respectively. The weight ratio of tegmen, seed coat and flesh of chestnut sample were 17.05, 14.9, and $68.05\%$, respectively. The total amino acid contents of flesh and seed coat were $2,994\;mg\%$ and $1,450\;mg\%$, respectively. The total amount of free amino acids was less than that of total amino acids. As results of mineral analysis, the content of K was higher than that of any other minerals. The contents of maltose and sucrose were higher than those of fructose and glucose. The total polyphenol contents of tegmen, seed coat, fresh, leaf and bark were $9.56\;mg\%$, $0.047\;mg\%$, $0.23\;mg\%$, $15.44\;mg\%$ and $17.85\;mg\%$, respectively.

• Korean Journal of Food Science and Technology
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• v.17 no.4
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• pp.283-288
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• 1985

Fermented big eyed herring. Harengula zunasi, and slimy, Leiognathus nuchalis, were widely used and contributed in diet of people in southern coast of Korea. In this paper, in order to elucidate the taste compounds of fermented big eyed herring and slimy, the nucleotides and their related compounds, free amino acids, TMAO, betaine, total creatinine, and minerals were analyzed. In fermented big eyed herring, lysine, alanine, leucine, isoleucine and valine were dominant holding 88.6% of the total free amino acids while alanine, leucine, isoleucine and lysine in fermented slimy were dominant holding 84.4% of total free amino acids. In the nulceotide and their related compounds, hypoxanthine was the major component in both samples. The contents of betaine, TMA and total creatinine were 99.7mg%, 24.2mg% and 432.8mg% in fermented big eyed herring, 107.6mg%, 19.5mg% and 258.8mg% in fermented slimy, while the contents of TMAO appeared trace in both samples. In the minerals of both samples Na and Ca were dominant holding 37,471-45,100.8ppm, 14,117.1-19,948.1ppm, respectively. From the omission test and chemical analysis, it is concluded that the major taste compounds of fermented big eyed herring and slimy were amino acids such as alanine, lysine, leucine and isoleucine. Minerals, nucleotides and their related compounds, betaine and total creatinine acted as an auxiliary role in taste of both fermented samples.

• Korean Journal of Plant Resources
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• v.34 no.2
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• pp.177-185
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• 2021

The purpose of this study was to compare the chemical properties of the bokbunja distributed in Korea with the content of the bioactive substance ellagic acid. The bokbunja was Rubus coreanus group and Rubus occidentalis group were compared, domestic bokbunja and import bokbunja were compared. In bokbunja, free sugar was 30.89 ± 0.7 mg/g of Rubus coreanus and 29.05 ± 0.87 mg/g of Rubus occidentalis. and 27.28 ± 7.4 mg/g of domestic bokbunja and 21.58 ± 6.73 mg/g of import bokbunja. The free amino acids was 4.50 ± 0.08 mg/g of Rubus coreanus and 5.05 ± 0.08 mg/g of Rubus occidentalis. and 4.13 ± 1.09 mg/g of domestic bokbunja and 3.75 ± 0.31 mg/g of import bokbunja. Validation of the ellagic acid method was confirmed by comparing the retention time and spectrum of the standard and extract using HPLC. The calibration curve (R²) showed linearity of 0.9999. As a result of analyzing the ellagic acid content of each extraction solvent, DMSO and methanol mixture extracts were high, and Rubus coreanus was 2.56 mg/g and Rubus occidentalis was 3.16 mg/g, which was not significantly different (p < 0.05) In addition, the ellagic acid content of domestic bokbunja and import bokbunja was 2.83 mg/g and 2.99 mg/g, which was not significantly different (p < 0.05).

• The Korean Journal of Ecology
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• v.27 no.5
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• pp.263-267
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• 2004

The collecting amount of sap by DBH class and contents of mineral and free sugar in the sap of Acer mono in Mt. Jiri were investigated. The total amount of sap throughout the study period was 315 L. Sap of A. mono were increased with increasing DBH, 67 L(21%), 104 L(33%) and 144 L(46%) from small (below 18㎝), middle (20-28㎝) and large (above 30㎝) diameter tree, respectively. This may be due to increase in crown width and extension of root system. Amounts of sap was required by big temperature fluctuation in day and night. The contents of solid, ash and sugar were 1.90%, 0.02% and 1.64% in the sap of A. mono. Free sugar determined in the sap was sucrose with 16.4 g/L, but glucose, fructose and maltose were not detected. The sap of A. mono was composed of seven kinds of mineral. The prominent minerals in the sap were Ca and K and the concentrations were 548㎎/L and 303㎎/L, respectively.

• Membrane Journal
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• v.12 no.4
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• pp.240-246
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• 2002

New polysulfone scintillation proximity membranes were prepared by impregnating Cerium Activated Yttrium Silicate (CAYS), an inorganic fluor, in a membrane structure. The membranes were applied to detect the radionuclide contamination directly without the aid of a scintillation cocktail. The preparation of membranes was divided into two processes. A supporting polymer film was made of casting solutions consisting of polysulfone and solvent, their cast film being solidified by vacuum evaporation. CAYS-dispersed polymer solutions were cast over the first, solidified polymer films and coagulated either by evaporating solvent or by exchanging solvent in the solution with nonsolvent in a coagulation bath. The prepared membranes had two distinguished, but tight1y attached, double layers: one is the supporting layer of dense polymer film and the other the detecting layer consisting of CAYS and polymer. The radionuclide counting results revealed that the prepared membranes were efficient to monitor radioactivity contamination with reliable counting ability.

• The Korean Journal of Food And Nutrition
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• v.13 no.5
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• pp.440-445
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• 2000

To develop a new processed foods with prepersimmon, the contents of approximate composition, free sugar, organic acid, mineral and vitamins in prepersimmon(Diospyros kaki Thumb. cv. Fuyu) were investigated. The approximate composition was 89.08% of moisture, 0.26% of crude ash, 0.56% of crude fat and 0.75% of crude protein respectively. Free sugars were composed of glucose, fructose and sucrose. Glucose(3.34%) and fructose(3.01%) were major free sugars, and sucrose was detected a small quantities. The organic acids were composed of citric acid. maleic acid, fumalic acid and lactic acid. Lactic acid(68.65mg%) was major a organic acid and took 79% of total organic acid amount. Minerals were K, P, Na. Ca, Fe and Zn, and K was a major mineral and detected 126.l2mg%, and Fe and Zn were a small quantities. The content of vitamin A was 33.95 R.E., and less than that in hard persimmon, and the content of vitamin C was 171.01 mg%, 10 times higher in comparison with that in hard persimmon, and vitamin B$_1$ and B$_2$ were detected a small quantities.

• Food Science and Preservation
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• v.14 no.1
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• pp.100-104
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• 2007

This study was designed to investigate quality characteristics and conditions of acetic acid fermentation of kiwi vinegar following addition of oligosaccharide. During the acid fermentation alcohol concentration and total acidity were shown to be 6% and 1.0%, respectively, with the highest acetic acid yield. Acetic acid fermentation of kiwi following addition of oligosaccharide showed the highest acetic acid yield with 15% oligosaccharide. Free forms of sugars in kiwi vinegar were detected to be fructose, glucose and maltose. Organic acid of kiwi vinegar were malic, lactic, acetic, citric and succinic acid. Total content of organic acid was shown to be the highest with 15% oligosaccharide. Mineral content was shown to be lower when oligosaccharide amount was increased. In conclusion, oligosaccharide addition has an insignificant effect on acetic acid fermentation of kiwi, and was evaluated to be suitable at 15%.