• 한국응용과학기술학회지
• /
• 제31권4호
• /
• pp.694-702
• /
• 2014

마이크론 크기를 가지는 ITO(indium tin oxide) 입자들은 인듐과 틴의 수용성 전구체들과 유기 첨가제를 분무 열분해하여 얻었다. 유기 첨가제로서는 에틸렌글리콜과 시트르산을 이용하였다. 분무 열분해 시 에틸렌글리콜과 시트르산과 같은 유기첨가제를 첨가하지 않고 얻어진 ITO 입자들은 구형이며 속이 꽉찬 형태를 가지는데 비해 유기 첨가제를 첨가하여 분무 열분해를 하면 얻어지는 ITO 입자들은 유기 첨가제의 양이 증가 할수록 껍질이 얇고 다공성이 증대된 중공 입자가 얻어진다. 유기첨가제를 첨가하지 않고 분무 열분해를 통해 얻어지는 마이크론 크기를 가지는 ITO는 $700^{\circ}C$에서 두 시간 동안의 후소성과 24 시간동안의 습식 볼밀링에 의해 나노 크기의 ITO로 전환되지 않으나, 유기첨가제를 첨가하고 분무 열분해를 통해 얻어지는 마이크론 크기를 가지는 ITO는 $700^{\circ}C$에서 두 시간 동안의 후소성과 24 시간 동안의 습식 볼밀링에 의해 나노 크기의 ITO로 쉽게 전환되었다. 응집된 나노 크기의 ITO의 일차 입자의 크기를 Debye-Scherrer 식에 의해 계산하였고 ITO 입자를 압축하여 만든 펠렛의 표면저항을 측정하였다.

• 한국응용과학기술학회지
• /
• 제30권2호
• /
• pp.290-296
• /
• 2013

We analysed interfacial traps in organic thin-film transistors (TFTs) in which pentacene and 6,13-bis(triisopropylsilylethynyl)-pentacene (TIPS-pentacene) organic semiconductors were deposited by means of vacuum-thermal evaporation and drop-coating methods, respectively. The thermally-deposited pentacene film consists of dentritic grains with the average grain size of around 1 m, while plate-like crystals over a few hundred microns are observed in the solution-processed TIPS-pentacene film. From the transfer characteristics of both TFTs, lower subthreshold slope of 1.02 V/decade was obtained in the TIPS-pentacene TFT, compared to that (2.63 V/decade) of the pentacene transistor. The interfacial trap density values calculated from the subthreshold slope are about $3.4{\times}10^{12}/cm^2$ and $9.4{\times}10^{12}/cm^2$ for the TIPS-pentacene and pentacene TFTs, respectively. Herein, lower subthreshold slope and less interfacial traps in TIPS-pentacene TFTs are attributed to less domain boundaries in the solution-processed TIPS-pentacene film.

• 한국지하수토양환경학회:학술대회논문집
• /
• 한국지하수토양환경학회 2002년도 총회 및 춘계학술발표회
• /
• pp.246-249
• /
• 2002

Black shale that has relatively high organic carbon content was tested to determine its sorption phenomena and capacity for TCE. Conventional batch sorption tests were peformed at room temperature. The parameters that were thought to affect the TCE sorption were solution pH and dissolved organic matter. The effect of solution pH on TCE sorption was minimal, but the dissolved organic matter increased the amount of TCE sorbed on black shale. Thus, using black shale as sorbent for TCE in groundwater could save material costs by replacing high cost conventional activated organic carbon.

• KSBB Journal
• /
• 제9권1호
• /
• pp.63-71
• /
• 1994

During the last decade enzyme reaction in organic solvent has been studied to show that specificity in buffer is different from that in organic solvent. The specificity of restriction enzyme was effected by various factors such as ionic strength, salt organic solvent and temperature. In this study, restriction enzyme PvuII which is used most frequently in genetic engineering and the substrate was vector pGEM3 whose sequence was already known were used. As a result the recognition sequence site was changed in the presence of organic solvents whose Log P are -1.5∼0. Their specificities were contrast with activities were contrasted. Specificities were not changed in organic solvent easily in inactivating enzyme. We think that the enzyme recognition site was not changed randomly but by preferential order. A recombinant vector which does not contain typical cleavage site CAG↓CTG was cleaved in 20% ethanol solution. This result might show that restriction enzyme could be used to cleave at unusual sites by changing the reaction conditions.

• 한국전기전자재료학회논문지
• /
• 제15권11호
• /
• pp.963-968
• /
• 2002

In this work, porous silicon (PS) layer is investigated as a sensing material to detect organic vapors such as ethanol (called alcohol), methanol, and acetone in low concentrations. To do this, PS sensors were fabricated. They have a membrane structure and comb-type electrodes were used to detect the change of electrical resistance effectively. PS layer on Si substrates was formed by anodization in HF solution of 25%. From fabricated sensors, current-voltage (Ⅰ-Ⅴ) curves were measured for gases evaporated from 0.1 to 0.5% organic solution concentrations at 36$\^{C}$. As the result, all curves showed rectifying behavior due to a diode structure between Si and the PS layer. The conductance of most sensors increased largely at high voltage of 5V, but the built-in potential on the measured Ⅰ-Ⅴ curve was lowered inversely by the adsorption effect of the organic vapors with high dipole moment.

• 공업화학
• /
• 제10권6호
• /
• pp.907-912
• /
• 1999

본 연구는 유기산염 및 알칼리 원료를 사용해 야채 및 과일등에 잔류되어 있는 농약 및 유성오염의 제거효과를 GC와 세정력 측정장치를 사용해 조사했다. 일반적으로 잔류농약 등의 유성 오염원을 제거하기 위해서는 합성세제, 유기용제 등의 여러 방법이 있지만 본 연구에서는 특별히 식품첨가물 원료만 사용했다. 알칼리 수용액상에서 trisodium citrate를 사용했을때 가장 우수한 결과를 나타냈는데, 기존의 화학 합성세제와 비교했을 때 우수한 농약제거력이 나타났다.

• 한국재료학회:학술대회논문집
• /
• 한국재료학회 2012년도 춘계학술발표대회
• /
• pp.64.1-64.1
• /
• 2012

Next generation displays such as high performance LCD, AMOLED, flexible display and transparent display require specific TFT back-planes. For high performance TFT back-planes, low temperature poly silicon (LTPS), and metal-oxide semiconductors are studied. Flexible TFT backplanes require low temperature processible organic semiconductors. Not only development of active semiconducting materials but also design and synthesis of semiconductor corresponding gate dielectric materials are important issues in those display back-planes. In this study, we investigate the high heat resistant polymeric gate dielectric materials for organic TFT and inorganic TFT with good insulating properties and processing chemical resistance. We also controlled and optimized surface energy and morphology of gate dielectric layers for direct printing process with solution processible organic and inorganic semiconductors.

• 한국해양공학회지
• /
• 제29권6호
• /
• pp.475-480
• /
• 2015

In this study, we developed a Cr-free organic/inorganic hybrid solution and investigated its coating properties on degraded STS316L. Both the OIBD-1 solution and OIBD-2 solution had excellent corrosion resistance and adhesion ability. However, the solution had some problems in a boiling water environment. In addition, the flexibility was excellent, and the scratch resistance was relatively good.

• 보존과학연구
• /
• 통권16호
• /
• pp.112-122
• /
• 1995

TEN-STORIED STONE PAGODA ON THE SITE OFWON-GAKSA(Temple) which is one of three marble pagodas in South Korea, were dated from the thirteenth year of the reign of King Sejo(1467). On the roof and surface of each the stories, there were large amount of the contaminants such as pigeon′s excretions, dust and environmental elements for a long time. The pH of contaminants is not acid, but is 7.2, neutral. To find the species of organic acidscontained in the contaminants and the degree of damaging for a marble pagoda, we analyzed the contaminants using GC-MSD method by the following procedures. Organic acids were extracted by saponifying whole contaminants. After Saponification, the organic acids were mathylated to increase their volatility upon subsequent GC-MSD analysis. The mathyl esters of the organic acids are extracted from the acidified aqueous solution. And the organic extracts were washed with adilute base solution. The washed extract were analyzed by GC(Hewlett Packard 5890)with a nonpolar capillary column(Crosslinked 5% Ph Me Silicone, $50×0.2㎜×0.33\mum$film thickness, USA) and Mass Spectrometric Detector(Hewlett Packard 5970B).As the result, it was found that 12 organic acids were the main compound in pagoda′contaminants, and the amount of organic acid were negligible.

• 동력기계공학회지
• /
• 제21권2호
• /
• pp.5-13
• /
• 2017

This study has developed an organic/inorganic hybrid solution according to amount of $SiO_2$ polysilicate, and the amount of melamine is constant. The three types of cold rolled steel were evaluated a corrosion resistance properties by using these solutions. $US_3M_3$ and $US_{11}M_3$ solutions were generate a lot of corrosion. $US_7M_3$ solution was excellent in corrosion resistance, regardless of the steel type. The appearance of coating by $US_3M_3$ and $US_{11}M_3$ solutions were bumpy surface, and were a lot of fine defects. $US_7M_3$ solution was made a sophisticated molecular cross-linking structure inside the coating, it was a slick surface. Other characteristics are exhibited the excellent property for all solutions.