• Polymer(Korea)
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• v.25 no.5
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• pp.609-616
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• 2001

The application of microwave technology to synthesis of polymer in solvent media has been shown by the synthesis of copper phthalocyanine (CUPc). The increase of synthetic yield-was demonstrated successfully in this study. A power variable microwave synthetic system has been developed with modifying cavity of domestic microwave oven and attaching microwave power controller. The properties of the specimen synthesized at various condition under the conventional thermal processing and microwave processing has been characterized by the means of chemical analysis, X-ray diffractometry (XRD), scanning electron microscopy (SEM), and particle size analysis (PSA).

• Journal of Pharmaceutical Investigation
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• v.10 no.3
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• pp.14-19
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• 1980

The dissociation constant of erythrosine in the mixed solvent systems of water-alcohols and water-acetone at various pH and in concentration media were determined by spectrophotometric method. Methanol, ethanol, and acetone were employed as solvents and studied the changes of pK values of erythrosine according to the kind and change of concentration of organic solvent which is mixed into water solution. The effect of organic solvent on pK is negligible at 40% while in the case of above 40% mixing, it is not negligible.

• Journal of Photoscience
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• v.10 no.1
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• pp.1-7
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• 2003

The results of recent work on the dye-sensitized photooxygenation of sulfides is discussed. In the case of dialkyl sulfides, the weakly bonded adduct initially formed with singlet oxygen (the persulfoxide) decays unproductively unless protonation by an acid (an alcohol or a carboxylic acid) facilitates its conversion to the sulfoxide. The effect is proportional to the strength of the acid (eg., less than 0.1 % chloroacetic acid in benzene is sufficient for maximal efficiency) and corresponds to general acid catalysis, suggesting that protonation of the persulfoxide occurs. On the other hand, with sulfides possessing an activated hydrogen in ${\alpha}$ position (eg., benzyl and allyl sulfides), hydrogen transfer becomes an efficient process in aprotic media and yields a S-hydroperoxysulfoniumm ylide, possibly arising from a conformation of the persulfoxide that is different from the one protonated in the presence of acids. Calculations on some substituted sulfides support this hypothesis. This process, which leads to C-S bond fragmentation with formation of an aldehyde, may be viewed as a general method for the preparation of aryl and heteroaryl aldehydes. In this effort, mechanistic studies offered new hints on the structure of the intermediate persulfoxide.

• Journal of Microbiology and Biotechnology
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• v.10 no.4
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• pp.532-534
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• 2000

The inhibitory effects of different Bifidobacterium spp. on the growth of Helicobacter pylori (HP) were investigated. A significant suppression of HP growth occurred only when HP was inoculated onto a petri dish containing 0.1 mg/ml of Bifidobacterium spp. When HP was separately cultured with B. breve K-110, B. catenulatum K-309, B magnum K-311, B. magnum K-321, and B. cuniculi K-513, the urease activity was also inhibited by these Bifidobacterium spp. Therefore, it appears that these Bifidobacterium spp. excrete a heat-labile inhibitory component for HP growth into the culture medium. Although most organic acids produced by the Bifidobacterium spp. inhibited the growth of HP, the HP growth was not inhibited by the physiological concentrations of organic acids produced in bifidobacteria-cultured media. Accordingly, these results suggest that some Bifidobacterium spp. may produce antibiotic-like compounds (bacteriocins).

• Proceedings of the KAIS Fall Conference
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• 2007.05a
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• pp.299-302
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• 2007

본 연구는 하 ${\cdot}$ 폐수 중의 유기물뿐만 아니라 질소, 인을 생물학적으로 제거하는 실험을 수행하였다. 공정 내 미생물의 유실을 방지하고 미생물이 고농도 상태로 유지 가능한 부착성장의 한 공법인 RBC에 끈상 나선형 미생물 접촉재를 설치한 반웅기를 이용하였다. 원수는 Glucose 1,800 mg/L, $NH_{4}Cl$ 500 mg/L, $KH_{2}PO_{4}$ 5mg/L를 혼합한 인공폐수를 제조하여 공정에 주입하였고, 그 결과 각각 미생물이 폐수에 적응하는 단계인 Period 1에서는 각 수질 분석 항목의 농도가 점차적으로 감소하는 경향을 보였으며, 정상상태라고 판단한 Period 2에서는 최종적으로 유입수에 대한 유출수의 제거율은 각각 $TCOD_{Cr}$ 94%, BOD 87%, T-N 85%, T-P 89%의 결과를 나타내었다.

• Journal of the Korean Applied Science and Technology
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• v.10 no.1
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• pp.83-91
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• 1993

The syntheses of urocanic acid esters was optimized, starting from p-toluenesulfonic acid salt of this acid and long chain fatty alcohols in the organic solvent and extracting water from it by means of azeotropic Compound. The salts of these urocanic acid esters showed amphoteric properties, but their micellization enhances their rate of hydrolysis leading to the free amine. Nevertheless the long chain gives to the esters themselves an amphoteric character allowing their solubilization in micellar media and in microemulsions the result, yield could enhanced.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.91-92
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• 2006

The fine-tuned dendrons provide unique supramolecular self-assemblies in various environments such as in water, organic media, and solid-liquid interfaces. They form nanotubes, vesicles, thin films, columns, lamellar nanoribbons depending on the condition of self-assembly process. Unique characteristics of self-assembly of the amide dendrons are described. In addition, elucidation of the structural correlation between the building blocks and the assemblies, stabilization of assembled structure, and transformation of supramolecular assemblies by using external stimuli. Particular emphasis is placed on the formation of cyclodextrin-covered organic nanotubes derived from self-assembly of amide dendrons and their supramolecular transformation. Finally, unique biosensory characteristics of the self-assembled nanotubes will be discussed.

• Bulletin of the Korean Chemical Society
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• v.26 no.9
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• pp.1321-1330
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• 2005

The use of ionic liquids as reaction media can confer many advantages upon catalytic reactions over reactions in organic solvents. In ionic liquids, catalysts having polar or ionic character can easily be immobilized without additional structural modification and thus the ionic solutions containing the catalyst can easily be separated from the reagents and reaction products, and then, be reused. More interestingly, switching from an organic solvent to an ionic liquid often results in a significant improvement in catalytic performance (e.g., rate acceleration, (enantio)selectivity improvement and an increase in catalyst stability). In this review, some recent interesting results which can nicely demonstrate these positive “ionic liquid effect” on catalysis are discussed.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.26 no.2
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• pp.92-97
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• 2013

In this paper the author proposes a method of implementing a numerical model for threshold voltage ($V_{th}$) shift in organic thin-film transistors (OTFTs) into SPICE tools. $V_{th}$ shift is first numerically modeled by dividing the shift into sequentially ordered groups. The model is then used to derive a simulations model which takes into simulation parameters and calculation complexity. Finally, the numerical and simulation models are implemented in AIM-SPICE. The SPICE simulation results agree well with the $V_{th}$ shift obtained from an OTFT fabricated without any optimization. The proposed method is also used to implement the stretched-exponential time dependent $V_{th}$ shift in AIM-SPICE and the results show the proposed method is applicable to various types of $V_{th}$ shifts.

• Journal of the Korea Furniture Society
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• v.25 no.2
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• pp.87-95
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• 2014

Since 1990s the concern on essence and inside has transferred onto the surface and its style. The longing for plastic surgery and skin beauty might prove this fervent tendency. Furthermore the development of digital media and technology as well as high-tech material enabled this hope to be real in the realm of design. All these progresses and transitions toward the surface introduced more creative and novel phenomena of furniture design arena around its surface. The rising of surface has evolved through architecture, interior design and furniture. The surface of furniture can be easily transposed into the human skin. And it acquires the aspects of skin's metaphoric and symbolic meaning. The characteristics of skin effect in furniture design can be summarized as material aspects, relational aspects, and formal aspects. Material aspects shows skin's elasticity and smooth plane. Relational aspects express the reactive functions of skin. Formal aspects represent organic power through surface.