• Bulletin of the Korean Chemical Society
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• 제35권6호
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• pp.1832-1836
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• 2014

A deep understanding of the metallic silver catalysts formation process on oxide support and the formation mechanism is of great scientific and practical meaning for exploring better catalyst preparing procedures. Herein the thermal decomposition process of supported silver catalyst with silver oxalate as the silver precursor in the presence of ethylenediamine and ethanolamine is carefully investigated by employing a variety of characterization techniques including thermal analysis, in situ diffuse reflectance infrared Fourier transform spectroscopy, scanning electron microscopy, and X-ray diffraction. The formation mechanism of supported silver particles was revealed. Results showed that formation of metallic silver begins at about $100^{\circ}C$ and activation process is essentially complete below $145^{\circ}C$. Formation of silver was accompanied by decomposition of oxalate group and removal of organic amines. Catalytic performance tests using the epoxidation of ethylene as a probe reaction showed that rapid activation (for 5 minutes) at a relatively low temperature ($170^{\circ}C$) afforded materials with optimum catalytic performance, since higher activation temperatures and/or longer activation times resulted in sintering of the silver particles.

• 대한본초학회지
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• 제36권5호
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• pp.29-36
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• 2021

Objectives : The purpose of this study was to fix the synonyms, origin, formation mechanism, description, and efficacy of Hwangnapchim in Elucidation of Materia Medica. Methods : Through searching histories and herbal classics, We categorized the contents, and compared with Aquilariae Lignum Resinatum. Results : The synonyms of Hwangnapchim were classified by 3 categories : Napchimhyang-type, Ganamhyang-type and Ginamhyang-type. In early period, it was called by Napchimhyang-type, named after its description that was similar to beeswax. Afterward it was called by Ganamhyang-type or Ginamhyang-type, because of the name "Kynam" that was called by in its producing region. And there were records of producing region of Vietnam, Cambodia, and being from abroad, while those of Vietnam were most frequent. According to custom duties of Ming Dynasty, Hwangnapchim was 17.5 times as expensive as Agarwood. Hwangnapchim shared main producing region, original plant, and process of formation with Agarwood. Therefore, its original plant was Aquilaria crassna, but added honey during formation process. Hwangnapchim was classified 5 types according to its description, the highest quality was Yu-gyeol, resembled beeswax, and easily recovered if get a scar. Hwangnapchim had a fragrance at room temperature, a spicy flavor, and the efficacy of blocking urine and feces. Conclusions : These results showed that Vietnam was major producing area of Hwangnapchim, and that it shared same origin with Agarwood, but it had different description, efficacy, and higher prices because of being added honey during formation.

• Journal of Veterinary Science
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• 제25권2호
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• pp.30.1-30.16
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• 2024

Background: Biofilms, such as those from Staphylococcus epidermidis, are generally insensitive to traditional antimicrobial agents, making it difficult to inhibit their formation. Although quercetin has excellent antibiofilm effects, its clinical applications are limited by the lack of sustained and targeted release at the site of S. epidermidis infection. Objectives: Polyethylene glycol-quercetin nanoparticles (PQ-NPs)-loaded gelatin-N,O-carboxymethyl chitosan (N,O-CMCS) composite nanogels were prepared and assessed for the on-demand release potential for reducing S. epidermidis biofilm formation. Methods: The formation mechanism, physicochemical characterization, and antibiofilm activity of PQ-nanogels against S. epidermidis were studied. Results: Physicochemical characterization confirmed that PQ-nanogels had been prepared by the electrostatic interactions between gelatin and N,O-CMCS with sodium tripolyphosphate. The PQ-nanogels exhibited obvious pH and gelatinase-responsive to achieve on-demand release in the micro-environment (pH 5.5 and gelatinase) of S. epidermidis. In addition, PQ-nanogels had excellent antibiofilm activity, and the potential antibiofilm mechanism may enhance its antibiofilm activity by reducing its relative biofilm formation, surface hydrophobicity, exopolysaccharides production, and eDNA production. Conclusions: This study will guide the development of the dual responsiveness (pH and gelatinase) of nanogels to achieve on-demand release for reducing S. epidermidis biofilm formation.

• 천문학회보
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• 제26권1호
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• pp.25-25
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• 2001

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 1998년도 특별강연 및 추계학술발표 개요집
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• pp.303-304
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• 1998

• 한국막학회:학술대회논문집
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• 한국막학회 1999년도 추계 총회 및 학술발표회
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• pp.27-30
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• 1999

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2001년도 춘계학술발표회 초록집
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• pp.44-45
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• 2001

• 한국세라믹학회:학술대회논문집
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• 한국세라믹학회 2003년도 춘계총회 및 연구발표회 초록집
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• pp.213.2-213
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• 2003

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2012년도 전기공동학술대회 논문집
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• pp.267-267
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• 2012

• 대한자기공명의과학회:학술대회논문집
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• 대한자기공명의과학회 2006년도 제11차 학술대회
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• pp.52-52
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• 2006