• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.317.2-317.2
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• 2013

Ultrathin oxide encapsulated metal-oxide hybrid nanocatalysts have been fabricated by a soft chemical and facile route. First, SiO2 nanoparticles of 25~30 nm size have been synthesized by modified Stobber's method followed by amine functionalization. Metal nanoparticles (Ru, Rh, Pt) capped with polymer/citrate have been deposited on functionalized SiO2 and finally an ultrathin layer of TiO2 coated on surface which prevents sintering and provides high thermal stability while maximizing the metal-oxide interface for higher catalytic activity. TEM studies confirmed that 2.5 nm sized metal nanoparticles are well dispersed and distributed throughout the surface of 25 nm SiO2 nanoparticles with a 3-4 nm TiO2 ultrathin layer. The metal nanoparticles are still well exposed to outer surface, being enabled for surface characterization and catalytic activity. Even after calcination at $600^{\circ}C$, the structure and morphology of hybrid nanocatalysts remain intact confirm the high thermal stability. XPS spectra of hybrid nanocatalyst suggest the metallic states as well as their corresponding oxide states. The catalytic activity has been evaluated for high temperature CO oxidation reaction as well as photocatalytic H2 generation under solar simulation. The design of hybrid structure, high thermal stability, and better exposure of metal active sites are the key parameters for the high catalytic activity. The maximization of metal-TiO2 interface interaction has the great role in photocatalytic H2 production.

• 공업화학
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• 제19권6호
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• pp.604-608
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• 2008

본 연구에서는 L-아스코르빈산(L-ascorbic acid: Vitamin C)을 점성이 낮은 비수계 오일상에서의 나노 캡슐화(nano-capsulation)에 대한 기초 연구가 수행되었다. 비수계에서 제조된 나노 캡슐체들은 500 nm 이하 크기를 나타냈으며 유화물형태에서의 평균 입자 크기는 410 nm로 나타났다. 온도와 저장 기간에 대한 안정도는 4, 20, $30^{\circ}C$ 온도에서 30일간 저장했을 때 최초 5일 후에는 5.1, 9.3, 12.5%의 L-아스코르빈산이 캡슐체로부터 유리되어 나왔으나 이후 기간 동안에는 약 1~2% 정도가 유리되어 나왔다. 또한, 남녀 각각 10명의 대상인원에 대한 피부 자극도는 1명만이 2일 후에 아주 미세한 피부 자극이 나타났으며 다른 인원에게서는 무자극성을 나타내었다.

• 대한화학회지
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• 제51권6호
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• pp.526-535
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• 2007

아다만탄 또는 β-cyclodextrin이 결합된 루테늄(II)-터피리딘 착화합물(8, 9, 11)을 합성하고 1H NMR, 13C NMR 및 질량분석스펙트럼으로 구조를 확인하였다. 아다만탄이 결합된 루테늄(II)-터피리딘 착화합물(8, 11) 은 물에 전혀 녹지 않으나, β-cyclodextrin 수용액에 혼합할 경우 β-cyclodextrin과의 초분자를 형성하여 물에 잘 녹아들어갔다. 비슷한 방법으로 수용액 중에서 루테늄(II)-터피리딘 착화합물(8, 11)을 각각 착화합물 9와 혼합 하였을 때, 착화합물(8, 11)의 아다만탄 부분이 루테늄 착화합물 9의 β-cyclodextrin 내부에 포접 됨으로써 안정 한 초분자를 형성하였다.

• 폴리머
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• 제39권1호
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• pp.6-12
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• 2015

난용성 약물인 아세클로페낙의 용해도를 개선하기 위해 약물과 고분자의 다른 비율을 사용하여 분무건조와 용매증발의 방법으로 Kollidon VA 64의 고체분산체를 제조하였다. 아세클로페낙을 포접하는 고체분산체의 형태학적, 물리화학적 분석을 하기 위해, 전자주사현미경(SEM), 푸리에변환 적외선분광법(FTIR), 시차주사 열량측정법(DSC) 등이 사용되었다. 포접률과 인공장액에서의 용출 거동은 HPLC를 사용하여 측정하였고, 비교를 위해 원약물과 시판제 Airtal$^{(R)}$이 사용되었다. 이것은 두 가지 방법에 따라 개선된 용출 거동을 나타내었다.

• 한국약용작물학회:학술대회논문집
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• 한국약용작물학회 2010년도 심포지엄 및 추계학술발표회
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• pp.296-297
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• 2010

• Journal of Dairy Science and Biotechnology
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• 제36권2호
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• pp.121-124
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• 2018

Ellagic acid (EA) is a naturally occurring polyphenolic compound in vegetables, nuts, and fruits such as berries. EA has antioxidant, anticancer, anti-allergy, and anti-inflammatory activities. The objectives of this research were to investigate the physicochemical properties of nanoparticles before and after nano-encapsulation of EA in dairy protein and to develop a functional (anti-inflammatory) dairy protein-based beverage containing EA. A particle size analyzer was used to determine the physicochemical and morphological properties. High performance liquid chromatography was used to evaluate the entrapment efficiency of EA. The nanoparticles containing EA were 100 to 200 nm in diameter. The determined poly dispersity index value of 0.3 to 0.4 indicated that the nanoparticles were uniformly distributed with similar size. Zeta-potential values were also similar between the control groups. The entrapment efficiency of EA was nearly 90%. The results indicate the potential for development of nanoparticles containing EA beverage products with anti-inflammatory activity.

• 한국유가공학회:학술대회논문집
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• 한국유가공기술과학회 2004년도 제59회 추계유가공심포지움 - 유가공 산업의 신기술 동향 및 발전 방향
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• pp.17-29
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• 2004

Nanofood can be simply defined as natural polymer particles containing functional food materials in nanoscale that are synthesized by polymerization or emulisification process. They have very uniform diameters in the range of 1 to 100 nm and extensive surface areas due to the small particle size in spite of their non-porosity. Although the technique to produce nanofood has not Bong developing history, many works have been achieved in various fields. Nanofood has a lot of special advantages, such as functionality, diversity, applicability, etc. In case of the domestic food industries, however, the accumulation of related technique is insufficient against developed countries except used food materials. Also, it is difficult to acquire technical know-how from the developed countries that possess those technologies. We have been studied on preparing functional nanofood and developing new production processes since 1999. Last 5 years we have laid the foundation on the preparation of nanofood and now are focusing on developing new processes of nanofood and expending the field of its applications.

• Journal of Applied Biological Chemistry
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• 제49권2호
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• pp.39-47
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• 2006

Incorporation of bioactive compounds such as vitamins, probiotics, bioactive peptides, and antioxidants into Nutrient Delivery System (NDS) for 'nanofood' provides simple way to develop novel functional foods that may have physiological benefits or reduce risks of diseases. As vital nutrient in nanofood, proteins possess unique functional properties including ability to form gels and emulsions, which allow them to be ideal nanofood materials for encapsulation of bioactive compounds. Based on protein physico-chemical properties, this review describes potential role of nanofood materials for development of NDS in hydrogel form, micro-or nano-particles. Applications of these nanofood materials to protect delivery-sensitive nutraceutical compounds are illustrated, and impacts of particle size on release properties are emphasized.

• 한국응용과학기술학회지
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• 제28권2호
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• pp.185-195
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• 2011

Carbon nanotube(CNT) plays an essential role in various fields of nano based science and technology. Recently, silica coated CNT composites are interested because they are useful for the optical, magnetical, and catalytic applications. In this report, carboxyl groups were introduced on the MWCNT using nitric acid. In order to maximize the silica encapsulation efficiency, carboxyl groups of MWCNT reacted with a silane coupling agent were used to prepare silica coated MWCNT. Due to their strong interaction between modified MWCNT and TEOS. Silica layer with a controllable thickness was achieved. Silica coated MWCNT were further utilized as the template for the synthesis of hollow silica nanotubes after $800^{\circ}C$ calcination.

• 한국약용작물학회:학술대회논문집
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• 한국약용작물학회 2009년도 심포지엄 및 춘계학술발표회
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• pp.103-104
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• 2009