• 펄프종이기술
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• 제47권6호
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• pp.139-146
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• 2015

We manufactured natural dyed Korean traditional paper (Hanji) for cultural properties conservation and storage with goldthread (Coptis chinensis) and silver nitrate ($AgNO_3$). Goldthread and silver nitrate are known to be an excellent antimicrobial activity. The effect of content of goldthread and silver nitrate on properties of dyed Hanji was investigated. Color strength of dyed Hanji decreased with increasing content of silver nitrate. After-mordanting with 3% silver nitrate improved lightfastness of dyed Hanji. Tannic acid treatment increased K/S value of dyed Hanji. As the amount of the increase in goldthread content was reduced silver nitrate content. Sim-mordanting method was used for simplifying manufacture process. Silver nitrate sim-mordanting method increased K/S value of goldthread than after-mordanting method.

• 반도체디스플레이기술학회지
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• 제11권2호
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• pp.23-26
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• 2012

The monodispersed polystyrene spheres were prepared by emulsion polymerization in aqueous alcohol system. They coated with silver by reduction of silver ion percolated on the surface of them. The spherical hollow type silver has been prepared by dissolving polystyrene with toluene. Epoxy resin compositions with spherical hollow type silver were manufactured, which were composed of a bisphenol F type epoxy resin (RE-304S), amine type hardener (Kayahard AA), and 1-benzyl 2-methyl imidazole (1B2MI) as catalyst. The electrical conductivity with silver content ratio were investigated after cure, the percolation threshold weight ratio for conductance in this epoxy resin system was obtained above the 70 wt% of silver.

• International Journal of Advanced Culture Technology
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• 제12권1호
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• pp.305-310
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• 2024

The purpose of this study is to implement game content within the generative artificial intelligence module Chat-GPTs, grounded in the humanistic discourse of self-reflection. This content aims to empower the dignity of the silver generation, which has been marginalized by digital technology. Simultaneously, we intend to prototype a digital psychotherapeutic tool. The development of a flexible device that adapts to the silver generation's living environment and temporal constraints is also part of our plan. However, there are still few commercially available products, and digital therapeutics developed in the form of content are virtually nonexistent. The goal is to implement game content that allows the elderly, who have been marginalized by digital technology, to find their true dignity. Simultaneously, we plan to commercialize a prototype of digital psychotherapy that can flexibly adapt to the range of living environments and time constraints of the elderly. This study has been extended based on the game content 'Daily Run' created by Hyein Kwon, an undergraduate student at Kyungil University.

• Restorative Dentistry and Endodontics
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• 제15권2호
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• pp.1-16
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• 1990

This study was to evaluate the cytotoxic effect in vitro and the tissue response within the rat peritoneal cavity to high copper amalgam and glass ionomer-silver cement, suggested for use as a retrograde endodontic filling material. In the cytotoxicity experiment, the radioactively ($^{51}Cr$) labeled L929 mouse fibroblasts were employed to determine the relative cytotoxicity of two experimental materials. Those materials were evaluated immediately after set and after one and seven days setting. In the tissue response experiment, two experimental materials were to evaluate mean peritoneal cellular count, differential cell count and the content of silver and copper in pooled packed cells and eluate samples taken by peritoneal lavage technique, and compared with surgical control after one day. two, four and six weeks of implantation. The results were as following: 1. High copper amalgam exhibited significant cytotoxicity immediately after set but showed no sign of toxicity after one day and seven days setting materials. 2. Glass ionomer-silver cement showed no sign of toxicity immediately after set and after one day and seven days setting. 3. High copper amalgam and glass ionomer-silver cement groups produce no significant difference in the mean peritoneal cell count when compared with the surgical control group after one day, two and four weeks of implantation. Surgical control group exhibited significantly a greater cell count when compared with the High copper amalgam group after six weeks. 4. High copper amalgam group increased significantly in the percentage macrophages after four and six weeks of implantation when compared with surgical control group. 5. The trace metal analysis involved an increased silver content in the elutes and an increased copper content in the packed cells of high copper amalgam group, and an increased silver content in the packed cells and elutes of glass ionomer-silver cement group.

• 한국세라믹학회:학술대회논문집
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• 한국세라믹학회 1986년도 Priceedings Of The Third Korea-Japan Seminar On New Ceramics
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• pp.259-267
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• 1986

The sintering behavior of silver-oxide glass composite thick-film has been studied with varing glass content. It is shown that during heat treatment glass became liquid phase to deeply affect the microstructure development of the silver particles and to control the physical properties of the thick-films. As glass content increased, the initial repacking of silver particles took place rapidly but the homogeneities of the microstructure showed different features. When the glass content was over some range, the silver particles exuded glass to decrease net energy and glass formed liquid pools separated from the solid skeletons. Finally the relations between the microstructures and electrical properties of the thick-film were discussed.

• 한국컴퓨터정보학회논문지
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• 제14권12호
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• pp.233-244
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• 2009

본 연구는 향후 40세 이상의 예비노인 및 노인들이 주도적으로 활용할 수 있는 전문 인터넷 포탈사이트를 실버포탈(silver portal)로 정의하고, 이러한 포탈이 향후 제공할 수 있는 콘텐츠 유형에 대하여 잠재 실버포탈 이용자들이 어떠한 선호도를 나타내는가를 파악하고자하였다. 특히, 본 연구에서는40세 이상의 예비노인의 개인의 특성(인구통계적 특성, 인터넷 이용 특성)에 따라 실버포탈이 제공할수 있는 콘텐츠 유형에 대한 선호도가 차이가 존재하는가를 탐색적 관점에서 파악함으로써, 향후 관련 실증연구들에서 적용하여 사용할수 있는 연구명제를 제시하고자 하였다. 이러한 연구목적을 달성하기 위해서, 본 연구에서는 서울과 경기지역에 거주하는 40세 이상의 인터넷 이용자들을 대상으로 설문지를 의뢰하여 실증적 통계분석을 수행하였다. 결과적으로, 본 연구는 개인의 여러 가지 특성에 따라 실버포탈의 콘텐츠 유형에 대한 선호도가 달라지는가를 파악할 수 있었으며, 이러한 분석결과를 토대로 향후 관련 연구들에서 적용할 수 있는 연구명제들을 제시할 수 있었다.

• Asian Pacific Journal of Cancer Prevention
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• 제15권16호
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• pp.6773-6779
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• 2014

Background: Nanotechnology opens new applications in many fields including medicine. Among all metallic nanoparticles, silver nanoparticles (silver NPS) have proved to be the most effective against a large variety of organisms including toxic cyanobacteria. Materials and Methods: Silver NPs were biosynthesized in vivo with different alga species namely, Spirulina piatensis, Chlorella vulgaris and Scenedesmus oh/iquus following two scenarios. First: by suspending a thoroughly washed algae biomass in 1 mM aqueous $AgN0_3$ solution. Second: by culturing them individually in culture media containing the same concentration of $AgN0_3$. Silver NPs were characterized using UV-Vis spectroscopy, transmission electron microscopy (TEM), energy dispersive analysis (EDX) and Fourier transform infra-red (FfIR) spectroscopy. The biosynthesized silver NPs were tested for cytotoxic activity against a cancer promoter cyanobacteruim Microcystis aeruginosa, considering effects on cell viability and chlorophyll content. Results: The surface plasmon band indicated the biosynthesis of silver NPs at ~400 nm. Transmission electron microscopy (TEM) revealed that the silver NPs had a mean average size below 100 nm. Energy-dispersive analysis X-ray (EDX) spectra confirmed the presence of silver element. FfIR spectral analyses suggested that proteins and or polysaccharides may be responsible for the biosynthesis of silver NPs and (-COO-) of carboxylate ions is responsible for stabilizing them. The toxic potentialities ofthe biosynthesized silver NPs against the cancer promoter cyanobacterium, Microcystis aeruginosa showed high reduction in viable cells count and the total chlorophyll content. Conclusions: The potential activity of the biosynthesized silver NPs from the studied algae species against Microcystis aernginosa cells is expected to be mainly mediated by the release of silver ions (Ag+) from the particle surface and bioactive compounds as indicated by FfIR analysis.

• Carbon letters
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• 제4권3호
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• pp.140-145
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• 2003

Antibacterial behaviors of PAN-based activated carbon fibers (ACFs) containing silver metal were investigated. The effects of surface and pore structures of the ACFs were studied by $N_2$/77 K adsorption and D-R plot as a function of silver loading content. The antibacterial activities were investigated by a dilution test against Staphylococcus aureus (S. aureus; gram positive) and Klebsiella pnemoniae (K. pnumoniae; gram negative). As experimental results, the ACFs showed some decreases in specific surface areas, micropore volumes, and total pore volume with an increase of silver content. However, the antibacterial activities of the ACFs were strongly increased against S. aureus as well as K. pnumoniae, which could be attributed to the presence of antibacterial metal in the ACFs system.

• 한국조리학회지
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• 제19권3호
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• pp.33-45
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• 2013

본 연구는 커피 실버스킨을 밀가루 중량에 대해서 0%, 3%, 5%, 7%로 대체 첨가하여 옐로우 레이어 케이크의 특성을 알아보았다. 반죽의 비중은 실버스킨 첨가량이 증가할수록 유의적으로 증가하였으며, 비용적은 실버스킨 함량이 많을수록 유의적으로 감소하였다. 부피지수는 실버스킨 첨가량이 증가함에 따라 유의적으로 감소하였으며, 대칭지수와 균일지수는 유의적인 차이가 없었다. 대조구의 부피지수, 대칭지수와 균일지수가 가장 높게 측정되었다. 조직감에서는 대조구가 가장 낮은 경도와 가장 높은 탄력성을 나타내었다. 시간이 경과함에 따라 실버스킨 첨가량이 많을수록 경도는 높아졌으나 탄력성은 낮아졌다. 관능검사 결과, 조직감을 제외한 모든 항목에서 대조구에 비해 실험군의 수치가 높았으며, 그 중에서 향과 맛은 SS5가 가장 높았고 외관과 전체적인 기호도는 SS3이 가장 높았다.

• 자원환경지질
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• 제21권3호
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• pp.223-234
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• 1988

A large number of gold and/or silver-bearing quartz veins occur in or near Mesozoic granite batholith elongated in a NE-SW direction within the Chungcheong Province. Precambrian schists and gneisses, and Jurassic and Cretaceous granitic rocks serve as hosts for gold and/or silver deposits. On the basis of Ag/Au total production and ore grade ratio, 15 mines may be divided into three major groups: gold-dominant deposits, gold-silver deposits, and silver-dominant deposits. The chemical composition of electrum from skarn deposit (Geodo mine), alaskite-type deposit (Geumjeong mine) and 15 vein deposits was summarized. It was found that the Au content of electrum for vein deposits ranging from 5.2 to 86.5 is lower than that for skarn and alaskite deposits. Among 15 vein deposits, the composition of electrum associated with pyrrhotite is relatively high and has a narrow range of 40.8 to 86.5 atomic % Au, but the Au content of electrum with pyrite is in range of 5.2 to 82.8 atomic %, and is clearly lower than that with pyrrhotite. The grouping of ages for these mines indicates that gold and/or silver mineralizations occurred during two periods in the Mesozoic. Daebo igneous activities are restricted to gold mineralization in the range of 158 to 133 Ma, whereas Bulgugsa igneous activities are related to gold and/or silver mineralization ranging from 108 to 71 Ma. Generally speaking, Jurassic gold-dominant veins have many common characteristics; notably prominent association with pegmatites, simply massive vein morphology, high fineness in the ore concentrates, rarity of silver minerals, and a distinctively simple mineralogy, including sphalerite, galena, chalcopyrite, pyrrhotite and/or pyrite. Although individual deposits exhibit widely differing diversity, Cretaceous gold-silver and silver-dominant veins are characterized by features such as complex vein, low to medium fineness in the ore concentrates and abundance of silver minerals including Ag sulfosalts, Ag sulfides, Ag tellurides and native silver.