• 대한화학회지
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• 제54권6호
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• pp.723-726
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• 2010

마이크로 반응을 이용하여 $NaHSO_4/SiO_2$을 촉매로 하는 solvent-free 합성을 통하여 $\beta$-enaminone 과 2-methylquinolin-4(1H)-one 및 그 유도체를 합성하는 효율적인 방법을 개발하였다. 반응 시간이 짧고, 수율이 좋았으며, 마이크로웨이브를 사용하지 않는 반응보다는 높은 선택성, 간단성, 무용매 반응 및 친환경적인 반응이다.

• Journal of electromagnetic engineering and science
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• 제16권1호
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• pp.7-12
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• 2016

This paper presents the design of a negative group delay circuit (NGDC) using the filter synthesis approach. The proposed design method is based on a frequency transformation from a low-pass filter (LPF) to a bandstop filter (BSF). The predefined negative group delay (NGD) can be obtained by inserting resistors into resonators. To implement a circuit with a distributed transmission line, a circuit conversion technique is employed. Both theoretical and experimental results are provided for validating of the proposed approach. For NGD bandwidth and magnitude flatness enhancements, two second-order NGDCs with slightly different center frequencies are cascaded. In the experiment, group delay of $5.9{\pm}0.5ns$ and insertion loss of $39.95{\pm}0.5dB$ are obtained in the frequency range of 1.935-2.001 GHz.

• 대한화학회지
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• 제51권6호
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• pp.520-525
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• 2007

Thiourea/urea, 다양한 aromatic aldehydes, ammonium acetate의 세가지 요소를 가지고 마이크로파의 조 사하에서 무수조건의 활성화된 비산화재를 촉매로 사용하여 높은 수율의 6-aryl-1,2,4,5-tetrazinan-3-thiones/ones를 얻었 다. 6-aryl-1,2,4,5-tetrazinan-3-thiones/ones의 구조는 녹는점, MS, IR, 1H NMR, D2O 교환, 13C NMR, 이차원의 NMR 스펙트럼(HOMOCOR, HSQC)을 바탕으로 증명되었다.

• 멤브레인
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• 제22권2호
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• pp.120-127
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• 2012

본 연구에서는 혼합 자일렌에서 에틸벤젠을 분리하기 위하여 제올라이트 분리막을 이용하였다. 마이크로웨이브 합성 온도에 변화를 주어 제조한 TS-1 제올라이트 결정을 알루미나 튜브에 성장시키기 위해 3-chloropropyltrimethoxysilane를 코팅 후 TS-1 nano seed를 안착시키고 마이크로웨이브 합성법을 이용한 2차 성장을 통해 3~4 ${\mu}m$의 두께를 가지는 얇은 TS-1 제올라이트 분리막을 제조하였다. 제조한 분리막을 이용하여 에틸벤젠/메타자일렌/파라자일렌이 혼합된 혼합 자일렌으로부터 에틸벤젠을 분리하였다. 마이크로웨이브 합성 온도가 증가할수록 제올라이트 결정의 크기가 비례하여 증가하였다. 또한 반응기의 온도가 $200^{\circ}C$에서 가장 높은 투과 플럭스와 선택도를 가졌다. 가장 좋은 에틸벤젠 분리 성능을 보인 분리막은 마이크로웨이브 합성 온도가 $170^{\circ}C$인 분리막이고 선택도 값은 2.64였다(에틸벤젠 투과 플럭스 : 1703.0 mol/$m^2{\cdot}s{\cdot}Pa$).

• 농약과학회지
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• 제13권2호
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• pp.117-125
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• 2009

Phenylformamidine계 유도체들은 곤충의 신경전달 물질인 octopamine과 경쟁적으로 octopamine receptor에 작용하여 살충 활성을 나타낸다. 불소를 함유한 4-fluoro-2-methylaniline과 2-fluoro-4-methylaniline을 트리에틸오르토포메이트와 반응시켜 얻은 중간체 formimidate(1)을 마이크로웨이브 조건하에서 반응시켜 짧은 반응시간 내에서 높은 수율로 새로운 화합물인 다양한 N', N'-fluorophenylformamidine 유도체들을 합성하였으며 이들 화합물의 복숭아 흑진딧물, 배추좀나방, 점박이응애, 그리고 벼멸구 등에 대한 살충활성을 시험하였다. 2-I-a, 2-I-c, 2-I-d, 2-II-d 화합물들이 응에류와 멸구유에 좋은 살충활성을 보여주었다.

• Bulletin of the Korean Chemical Society
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• 제31권2호
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• pp.351-354
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• 2010

Nickel nanoparticles (Ni NPs) appeared to exhibit the catalytic activity in one-pot cyclocondensation reaction for the preparation of 3,4-dihydropyrimidine-2(1H)-ones via Biginelli reaction from aromatic/heteroaromatic/aliphatic aldehydes, urea/thiourea and ethyl acetoacetate under microwave irradiation has been described. The UV absorbance spectra showed metallic Ni characteristics and appreciate with the particle size determined by Transmission electron microscopy (TEM). After reaction course the Ni NPs can be re-covered and reused without any apparent loss of activity.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 하계학술대회 논문집
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• pp.167-168
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• 2009

Phase pure barium magnesium tantalate $Ba(Mg_{1/3}Ta_{2/3})O_3$(BMT) nanopowders were synthesized at temperature as low as $220^{\circ}C$ through glycothermal reaction by using $Ba(OH)_2{\cdot}8H_2O$, $Mg(NO_3){\cdot}6H_2O$, and $TaCl_5$ as precursors and 1,4-butandiol as solvent. XRD, SEM, and TGA data support that glycothermal processing method provides a simple low temperature route for producing fine grained BMT nanopowders without alkaline mineralizers. BMT nanopowders synthesized at $220^{\circ}C$ showed more homogenous with rounded morphologies.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1990년도 추계학술대회 논문집 학회본부
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• pp.97-100
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• 1990

Diamond thin films were synthesized by the MPECVD (Microwave Enhanced Chemical Deposition) using the mixture of the hydrogen and organic compounds($CH_3COCH_3$, $CH_3OH$). In X-ray Diffraction, the d values of all the deposits on the Si substrates with the experimental conditions coincide with those of natural diamond in POD (Powder Diffraction Data). The changes of the morphology of all the deposits were examined by SEM. The amount of amorphous carbon or graphite in the diamond films were increased as the acetone concentration was increased. The morphology of the diamond particles can be changed from ball-like to euhedral by adding the small amount of the methanol in the reaction gases of the high acetone concentration.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1995년도 추계학술대회 논문집
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• pp.269-272
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• 1995

As methane concentration was varietal, the textures of diamond films deposited on Si(100)substrate could be observed by XRD, SEM and Raman spectroscope. As a result, O$_2$plasma etching has been useful to observe microscopic structure of diamond films by SEM. The cross section of diamond films deposited on Si(100) substrate with 4% concentration of methane to hydrogen was a polycrystal like a pillar. The diamond crystal like a pillar has been oriented to (110) surface and the high quality diamond with FWHM of Raman spectra being 3.8cm$\^$-1/ has been grown. As time goes by deposition time, the preferred orientation increases.

• E2M - 전기 전자와 첨단 소재
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• 제9권3호
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• pp.270-276
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• 1996

As methane concentration was varied, the textures of diamond films deposited on Si(100)substrate were observed by XRD,SEM and Raman spectroscope. As a result, $O_{2}$ plasma etching has been useful to observe microscopic structure of diamond films by SEM. The cross section of diamond films deposited on Si(100)substrate with 4% concentration of methane to hydrogen was a polycrystal like a pillar. The diamond crystal like a pillar has been oriented to (110)surface and the high quality diamond film with FWHM of Raman spectra being 3.8 $cm^{-1}$ / has been grown. As time goes by deposition time, the preferred orientation increases