• Proceedings of the Membrane Society of Korea Conference
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• 2004.05a
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• pp.191-194
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• 2004

A novel type of intelligent microcapsule reactor system was prepared. The reactor can recognize pH change in the medea and control reaction rate by itself. For the reactor system, acrylic acid (AA), N-isopropylacrylamide (NIPAM), and glucose oxidase (GOD) were selected as a pH-responsive device, a gating device according and a reaction device, respectively. Poly(NIPAM-co-AA) (P-NIPAM-co-AA) are known to change its hydrophilicity-hydrophobicity due to pH change. They were integrated in a core-shell microcapsule space. GOD was loaded inside the core space and the pores in the outside shell layer were filled with P-NIPAM-co-AA linear grafted chains as pH-responsive gates by plasma graft filling polymerization method. When P-NIPAM-co-AA gates are hydrophilic at high pH value, this microcapsule permits glucose penetration into the core space and GOD reaction proceeds. However, when P-NIPAM-co-AA gates are hydrophobic at low pH value, this microcapsule forbids glucose penetration and GOD reaction will not occur. The accuracy of this concept was examined.

• Journal of the Korean Applied Science and Technology
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• v.18 no.4
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• pp.273-284
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• 2001

A series of microcapsule were synthesized by using several PCM(Phase Change Material) as a core material and gelatin/arabic gum, melamine/formaldehyde as a shell material. Coacervation technique and in situ polymerization were adopted in synthesizing microcapsules. In the microencapsulation by coacervation, tetradecane and octadecane were used as core materials. In the microencapsulation by situ polymerization tetradecane, pentadecane, hexadecane, heptadecane, octadecane, and nonadecane were used as core material. The synthesized microcapsule was examined to observe the shape of the microcapsule. The particle size analysis was performed by particle size analyzer. The thermal properties(e.g. melting point, heat of melting, crystallization temperature, heat of crystallization, differences between melting point and crystallization temperature) were obtained by DSC(Differential Scanning Calorimeter). The stirring rate effect was investigated during the microencapsulation. It was found that with increasing the stirring rate much smaller microcapule was produced. However, this did not necessarily lead to formation of spherical microcapsule.

• Computers and Concrete
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• v.15 no.1
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• pp.37-54
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• 2015

In general, cracks significantly deteriorate the in-situ performance of concrete members and structures, especially in urban metro tunnels that have been embedded in saturated soft soils. The microcapsule self-healing method is a newly developed healing method for repairing cracked concrete. To investigate the optimal microcapsule parameters that will have the best healing effect in concrete, a 3D analytical probability healing model is proposed; it is based on the microcapsule self-healing method's healing mechanism, and its purpose is to predict the healing efficiency and healing probability of given cracks. The proposed model comprehensively considers the radius and the volume fraction of microcapsules, the expected healing efficiency, the parameters of cracks, the broken ratio and the healing probability. Furthermore, a simplified probability healing model is proposed to facilitate the calculation. Then, a Monte Carlo test is conducted to verify the proposed 3D analytical probability healing model. Finally, the influences of microcapsules' parameters on the healing efficiency and the healing probability of the microcapsule self-healing method are examined in light of the proposed probability model.

• Analytical Science and Technology
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• v.18 no.2
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• pp.97-103
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• 2005

The various size and morphology microcapsules were prepared to produce smell sweet by heating condensation reaction of melamine and formaldehyde using 5-types of surfactants such as the laurylbenzenesulfonic acid sodium salt (SDS), polyvinylpyrrolidon (PVP), polyvinyl alcohol (PVA), Span-80 and 2-acrylamido-2-methyl-1-1 propanesulfonic acid (AMP). As result it was found that the size and morphology of microcapsule is intimately associated with a kind of surfactants. In order to prepare microcapsule with antibacterial, the silver nanoparticle was prepared by gamma-irradiation. microcapsule with silver nanoparticle was prepared.

• Korean Journal of Food Science and Technology
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• v.32 no.1
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• pp.42-49
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• 2000

A new method for the quantitative determination of capsaicinoids in microcapsule has been developed. Among seventeen solvents tested for solubilizing wall material (gum arabic and modified starch) of microcapsule, dimethyl sulfoxide (DMSO) was selected as an optimal solvent. The most appropriate mixing ratio of microcapsule to DMSO for solubilizing wall material was 1 to 10(w/v). Appropriate carriersolubilizing temperature and time were $55^{\circ}C$ and 30 min, respectively. Also conditions for extracting oleoresin from the solubilized microcapsule were studied. The mixing ratio of ethanol to DMSO was optimal at 8 to 1(v/v). Optimized vortexing time was 5 min at 40㎐. Pecipitant was obtained by centrifugation at 21000 rpm for 15 min. The precipitant was reextracted with ethanol. The extracted supernatants were combined and adjusted to final volume of 25 ml. Extracted solutions were analyzed for quantitation of total capsaicinoids by employing HPLC and for quantitation of total carotenoids by spectrophotometric method. This method can be used to monitor changes of capsacinoid during manufacturing or storage of red pepper oleoresin microcapsule powder.

• Korean Journal of Food Science and Technology
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• v.39 no.1
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• pp.66-70
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• 2007

Lactobacillus fermentum YL-3 was encapsulated to increase acid tolerance and its total viability. After micro-encapsulation of L. fermentum YL-3 cells with sodium alginate and soybean oil, the morphology of the microcapsule was observed using confocal laser scanning microscopy (CLSM) after staining with pyronin Y and fluorescein isothiocyanate. The sizes of the microcapsules were 120-126 ${\mu}m$, 444-486 ${\mu}m$ and 401-463 ${\mu}m$ when manufactured at pH 2, 3 and 4, respectively. The microcapsule could hold live cells of L. fermentum YL-3 up to $1.2{\times}10^{7}$, $8.1{\times}10^{7}$ and $1.1{\times}10^{8}$ CFU/mL at pH 2, 3 and 4, respectively. The acid tolerance and preservative ability of L. fermentum YL-3 in microcapsule and macrocapsule at $4^{\circ}C$ and $25^{\circ}C$ were tested. L. fermentum YL-3 cells were evenly located in the alginate capsule matrix structure and the firmness of microcapsule was highest at pH 2. Micro-encapsulation showed the most effective acid tolerance at pH 2.0 and preservation of viability at $4^{\circ}C$. However, at $25^{\circ}C$, the macrocapsules showed more effective cell protection than the microcapsules. The application range for microcapsules could be wider than for macrocapsules in the food industry.

• Proceedings of the KSME Conference
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• 2001.11a
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• pp.716-722
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• 2001

In this paper, the modeling and control of electrostrictive polymer is introduced for endoscopic microcapsule. The endoscopic microcapsule works in the body, so the material of robot must be no harmful to the body. The electrostrictive polymer satisfies this condition. The modeling and control of endoscope microcapsule must be processed. So the modeling and control of electrostrictive was processed preferentially. The electrostrictive polymer is so flexible that we considered the electrostrictive polymer as flexible membrane. The dynamic equation of flexible membrane is time variant in electrostrictive polymer. It is the reason that the elastic modulus of electrostrictive polymer is very small and changes as deformation of electrostrictive polymer. The control algorithm must overcome these characteristics. So the algorithm of adaptive fuzzy control was used to control. In this paper, we introduced the dynamic modeling and control of electrostrictive polymer. And its deformation is introduced.

• Fashion & Textile Research Journal
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• v.23 no.6
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• pp.836-843
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• 2021

Recently, with an increase of interest in hygiene of textile products, research related to finishing technology to impart various functionalities, such as antibacterial and deodorizing properties, has also required. Therefore, in this study, the improvement of comfort was examined by analyzing the change of moisture characteristics and antibacterial and deodorizing properties of underwear fabric by chitosan microcapsule(CH-M) finishing. The results revealed that moisture absorption time of the fabric shortened, diffusion rate increased, while absorption rate slightly increased because of microcapsule finishing. In addition, the one-way transfer capacity of the microcapsule finished fabric was 17.69, which improved moisture transfer to one side, while OMMC showed the values of 0.32 and 0.37 for untreated and finished fabrics, respectively, which slightly increased after finishing. In the case of untreated fabric, antibacterial activity was 89.0% against Staphylococcus aureus and 70.3% against Klebsiella pneumoniae; however, both strains showed 99.9% antibacterial activity by CH-M finishing. An excellent bacterial reduction rate was also observed. In the case of the CH-M finished fabric, there was a deodorization effect exceeding 99% up to 120 minutes, and it showed an excellent deodorization effect of more than 99% even after 10 repeated washings.

• Proceedings of the Membrane Society of Korea Conference
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• 1995.04a
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• pp.48-49
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• 1995

금년에 고도화 사회의 진전을 배경으로 여러분야에서 섬유고분자재료에 대하여 보다 기능성이 요구되고 있다. 그 중에서도 가장 중요한 기증중의 하나인 감성과 정서, 쾌적 기능의 요구와 더불어 기능성 물질의 합성과 추출, 섬유에의 복합화 기능에 대하여 활발한 연구가 진행되고 있다. 기능성 물질의 섬유에의 복합화 가공은 섬유재료와 여러 공정 조건의 복합적 요소에 의하여 좌우되며 기능성 물질의 흡착, 포괄방법에서 일반적으로 흡진, 혼합방사, microcapsule에 의한 봉입처리를 후가공법으로 행해오고 있고 특히 기능성 물질의 안정적 측면에서 microcapsule에 의한 기능성 부여에 대한 연구가 특히 주목을 받고 있다.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.28 no.8
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• pp.518-523
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• 2015

We fabricate a single particle-microcapsule type electronic paper using electrophoresis, which is different with a reported dual particle-microcapsule type and of which electro-optical researches are not reported. So we analyzed a basic properties, such as reflectivity, response time, and driving voltage. Our display panels having various cell-gaps of $30{\mu}m$, $34{\mu}m$, $38{\mu}m$, $42{\mu}m$, and $46{\mu}m$ are inspected. As a results, a driving voltage is defined to 10 V and desirable cell-gap is $30{\mu}m$ or $34{\mu}m$. Considering a mechanical strength, the optimum cell-gap is $34{\mu}m$ for the single particle type electronic paper.