• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.47 no.6
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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.

• Journal of the Semiconductor & Display Technology
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• v.11 no.2
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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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• v.12 no.1
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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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• v.15 no.2
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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.

• Proceedings of the Korean Ceranic Society Conference
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• 1986.12a
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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.

• Journal of the Korea Society of Computer and Information
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• v.14 no.12
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• pp.233-244
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• 2009

This study defines the silver portal as a specialized internet portal that will be probably popular with the pre-senior/senior internet users who are over 40, sooner or later. The purpose of the study is to analyze what types of online contents on the silver portal are mostly preferred by the pre-senior/senior, and does the preference of those content types vary according to the demographic and the internet usage characteristics of the pre-senior. The study also is to suggest some research propositions, based on the analysis results, that could be applied to empirical studies in the future which deal with various research questions on the silver portal. To accomplish these research purposes, the study performed a survey for the prospective silver portal users who are living in the areas of Seoul and Kyeonggi, South Korea, and did various statistical analyses. This study found that the preference of content types of the silver portal vary according to some personal characteristics of the prospective silver portal users, and moreover proposed a few of research propositions on the relationships between personal characteristics and preferred content types.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.16
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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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• v.4 no.3
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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.

• Culinary science and hospitality research
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• v.19 no.3
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• pp.33-45
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• 2013

This study was conducted to evaluate the effect of substitution of the flour with coffee silver skin (at the levels of 0%, 3%, 5%, and 7%) on the characteristics of yellow layer cake. The specific gravity of batter increased significantly as the content of silver skin increased. The specific volume of cake decreased significantly as the content of silver skin increased. The volume index decreased significantly as the silver skin content increased, while the symmetry index and uniformity index were not influenced. It was found that control had the highest cake indexes. Texture analysis showed that control had the lowest hardness and highest springiness. Hardness value of cakes was increased by adding silver skin; however, the springiness value of cakes with silver skin decreased during storage. According to sensory evaluation, experiment groups scored the higher points in texture acceptance than control. Above all, SS5 scored the highest points in aroma, taste and SS3 scored the highest points in appearance and overall acceptance.

• Economic and Environmental Geology
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• v.21 no.3
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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.