• Bulletin of the Korean Chemical Society
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• 제31권10호
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• pp.2961-2966
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• 2010

Reduction of carbonyl compounds such as aldehydes, ketones, $\alpha,\beta$-unsaturated enals and enones, $\alpha$-diketones and acyloins was carried out readily with $NaBH_3CN$ in the presence of wet $SiO_2$ as a neutral media. The reactions were performed at solvent-free conditions in oil bath (70 - $80^{\circ}C$) or under microwave irradiation (240 W) to give the product alcohols in high to excellent yields. Regioselective 1,2-reduction of conjugated carbonyl compounds took place in a perfect selectivity without any side product formation.

• Elastomers and Composites
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• 제50권4호
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• pp.274-278
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• 2015

Nanosized gold particles were synthesized by microwave irradiation in a mixture composed of potassium tetrachloroaurate(III) n-hydrate, sodium citrate dihydrate and Tween 20. The synthesized gold particles were characterized by UV-vis spectrophotometer, scanning electron microscopy, and X-ray diffraction techniques. Using UV-vis spectroscopy, it was confirmed that gold nanoparticles act as a catalyst in the reduction of 4-nitroaniline with sodium borohydride to form 1,4-diaminobenzene. Additionally, we studied the kinetics of this reductive reaction in the presence of these gold nanoparticles under various conditions.

• 대한화학회지
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• 제48권2호
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• pp.177-181
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• 2004

1,2,4-트라이아졸, 피라졸론, 그리고 1,3,4-옥사다이아졸을 마이크로파 쬐임(MWI) 하에서 여러 가지 고체지지체를 이용하여 치환기가 있는 하이드라자이드로부터 합성하였다. 그 얻어진 실험 결과들은 고체지지체의 다양성을 보여준다. 합성한 모든 유도체들을 A. niger와 A. flavus 균주에서 항진균성활성도를 조사한 하였으며 좋은 활성을 보여 주었다.

• 신재생에너지
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• 제9권2호
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• pp.5-14
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• 2013

The efficiency of microwave-assisted acid hydrolysis of seaweeds for the production of ethanol was investigated and its effect on hydrolysis into reducing sugar and fermentation into ethanol evaluated as compared with those by conventional heating. A brown seaweed, Laminaria japonica (10-100g/L) was hydrolysed under dilute acidic condition (0.5N $H_2SO_4$, $100^{\circ}C$) with two sorts of heating: microwave irradiation for ${\leq}10min$ and conventional heating for 10-60min. Microwave-assisted hydrolysis was shown to be more efficient. A similar range of reducing sugar and ethanol yields as with the conventional autoclave heating procedure(${\geq}30min$) was observed, but it was obvious that production of ethanol from microwave-assisted hydrolysis had a 3 times faster reaction rate leading to very short production times, lower energy consumption/loss than from the conventional heating mode, and higher biomass loading without significant reducing ethanol yield, thus microwave-assisted acid hydrolysis is a potential alternative method for more effective hydrolysis of Laminaria japonica.

• 한국작물학회지
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• 제64권4호
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• pp.366-372
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• 2019

본 연구에서는 알러지 반응 저감의 특성을 가지고 있는 오프리 밀가루를 이용하여 적절한 물리적 방법을 통해 제과적성을 개선시키고자 하였다. 오프리 밀가루는 높은 단백질 및 글루텐 함량을 가지고 있어 쿠키를 제조하였을 때 가공적성이 낮은 특징을 가지고 있다. 밀가루에 대한 마이크로웨이브 조사는 글루텐의 형성에 영향을 미친다는 보고에 따라, 본 연구에서는 오프리 밀가루에 마이크로웨이브 조사를 통해 제과 가공적성을 개선하고자 하였다. 그 결과, 마이크로웨이브조사는 오프리 밀가루의 단백질의 함량 및 글루텐 함량에는 영향을 미치지 않았지만 이를 이용하여 쿠키를 만들었을 때 퍼짐성과 균열정도가 개선되는 것을 확인 할 수 있었다. 이는 마이크로웨이브조사가 글루텐 형성에 영향을 미쳐 반죽점도를 감소시켜 쿠키의 가공적성이 개선되는 것을 확인 할 수 있었다. 하지만 과도한 열처리는 단백질의 변성을 유도하여 오히려 가공적성을 감소시켰고, 이에 따라 사용목적에 따른 적절한 처리조건을 규명하는 것이 필요하다. 따라서 이러한 연구결과를 통해 높은 단백질 및 글루텐함량을 가지고 있는 밀가루를 대상으로 적절한 마이크로웨이브와 같은 물리적 처리를 통해 가공적성을 개선하여 활용도를 높일 수 있을 것으로 예상된다.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.199-199
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• 2006

Microwave-irradiation has become a common heat source in organic chemistry in the last decade. In recent years, polymer chemists also discovered the advances of microwave heating that include fast and efficient heating as well as the homogeneous heat profile and the easy access to pressurized reaction conditions. In this contribution, we report our investigations on the cationic ring-opening polymerization of 2-oxazolines that lead to a tremendous acceleration from several days to several minutes polymerization time. In addition, the optimized microwave-assisted polymerization procedure was applied for the preparation of libraries of diblock and triblock copolymers that were used for the determination of structure-property relationships in poly(2-oxazoline)s.

• Carbon letters
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• 제1권3_4호
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• pp.143-147
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• 2001

Under the irradiation of radiofrequency wave, the dipole materials vibrate as microwave phase changes. This causes friction between adjacent molecules and enables an unique characteristics of interior heating of the materials. Using this principle, when harmful material pass through anthracite- bed which play a role as a absorber of radiofrequency wave, the material can be easily decomposed by the microwave energy. To remove benzene vapour and other solvents in the process of industry, we examined decomposition of benzene in this manner. It was found that benzene was decomposed to the methane, ethane, propane and butane, etc. during passing through the carbon-bed under the microwave impingement and distribution of methane in the products reached about 85 vol.%. The decomposition rate of benzene was high within 5 minutes from start of reaction. For a lower concentration of benzene gas, general cases in the field of industry, almost complete decomposition of benzene is believed possible and this method is surely expected to be useful for the prevention of air pollution and improvement of ambient condition.

• 대한화학회지
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• 제45권6호
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• pp.546-548
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• 2001

클로로술폰산을 실리카겔과 반응시키면 실리카겔 표면에 황산이 공유결합으로 고정된 실리카황산을 얻게 된다. 무용매 조건하에서 마이크로웨이브를 쪼여주면서 실리카 황산과 젖은 $SiO_2$를 함께 사용하게 되면 아세탈을 화합물로 변화시키는 효과적인 탈아세탈 시약으로 사용할 수 있다.

• Bulletin of the Korean Chemical Society
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• 제30권7호
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• pp.1628-1630
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• 2009

• 대한화학회지
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• 제49권4호
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• pp.370-376
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• 2005