• Korean Journal of Microbiology
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• v.37 no.4
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• pp.273-276
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• 2001

The strain which accumulate the silver in cell were isolated and characterized. And condition of accumulation of heavy metal was examined closely to investigate optimal condition of accumulation. Pseudomonas fluorescens and Bacillus cereus were Isolated from groundwater as the strain of silver accumulating bacteria. These strains did not grow in the medium at silver over the concentration 20 ppm. The largest accumulations of silver in the culture of Pseudomonas fluorescens and Bacillus cereus occurred within 24 hours. The amount of silver accumulation in Pseudomonas fluorescens and Bacillus cereus were 1.9 mg/g cell and 1.65 mg/g cell, repletively. In protein patterns of cell after the treatment of silver, three reducible proteins (126 KDa, 89 KDa, 25 KDa) in Bacillus cereus and one new protein (34 KDa) in Pseudomonas fluorescens were detected by SDS-PAGE.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2015.11a
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• pp.249-249
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• 2015

Silver films have been of considerable interest for years due to their better performance relative to other metal films for engineering applications. A series of multi-layer silver coatings with different thickness (i.e. 0.3 um to 1.5 um) were prepared on Aluminium substrate containing copper undercoat by direct current (DC) magnetron sputtering method. For the comparative purpose, similar thickness silver coatings were prepared by electrolytic deposition method. Microstructural, morphological, and mechanical characteristics of the silver coatings were evaluated by means of scanning electron microscope (SEM), X-ray diffraction (XRD), Surface roughness test, microhardness test and nano-scratch test. From the results, it has been elucidated that the silver films prepared by DC magnetron sputtering method has superior properties in comparison to the wet coating method. On the other hand, DC magnetron sputtering method is relatively easier, faster, eco-friendly and more productive than the electrolytic deposition method that uses several kinds of hazardous chemicals for bath formulation. Therefore, a New Work Item Proposal (NWIP) for the test methods standardization of DC magnetron sputtered silver coatings has recently been proposed via KATS, Korea and a NP ballot is being progressed within a technical committee "ISO/TC107-metallic and other inorganic coating".

• Environmental Analysis Health and Toxicology
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• v.25 no.3
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• pp.215-222
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• 2010

The market size of engineered nanoparticles is rapidly increasing due to the fast application of nanotechnologies into different industries and consumer products. The development of new technology and materials has improved human's quality of life, but it also entails the possibility of exposure to new materials. In this study, we compared the distribution in the body by the inflow of silver nanoparticles having another diameter and shape at 1 h or 24 h after injection via the tail vein. And, we compared the cell composition and cytokine concentration in BAL fluid, and histopathological changes. As results, discharge of silver nanoparticles having small diameter and sphere shape was more rapid than that of big diameter or plate shape. It is estimated that the toxicity in liver and lung was proportional to accumulation level. The persistence of inflammation was also longer in mice treated with plate shape. Consequently, we suggest that the first choice of silver nanoparticles having small diameter and sphere shape in applying is desirable.

• Bulletin of the Korean Chemical Society
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• v.33 no.10
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• pp.3191-3195
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• 2012

New silver nanoparticle (AgNP)-loaded amino acid based hydrogels were synthesized successfully from poly (vinyl alcohol) (PVA) and poly(acryl amide-co-acryloyl phenyl alanine) (PAA) by redox polymerization. The formation of AgNP in hydrogels was confirmed by using a UV-Vis spectrophotometer and XRD. The structure and morphology of silver nanocomposite hydrogels were studied by using a scanning electron microscopy (SEM), which demonstrated scattered nanoparticles, ca. 10-20 nm. Thermogravimetric analysis revealed large differences of weight loss (i.e., 48%) between the prestine hydrogel and silver nanocomposite. The antibacterial studies of AgNP-loaded PAA (Ag-PAA) hydrogels was evaluated against Escherichia coli (Gram-negative) and Staphylococcus aureus (Gram-positive) bacteria. These Ag-PAA hydrogels showed significant activities against all the test bacteria. Newly developed hydrogels could be used for medical applications, such as artificial burn dressings.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.11
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• pp.2419-2426
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• 2009

This paper is a study on the implementation of internet phone for silver generation based on RFID system. Together with the development of internet, the commercial internet phone is being used widely. However the usage of internet phone is still not convenient with silver generation. In this paper, we use one of the internet phone type called application method and 13.56MHz RFID technology to improve the usage of internet phone. The new silver internet phone can make a phone call only by using RFID tag that has a picture or some information of callee.

• Macromolecular Research
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• v.12 no.4
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• pp.391-398
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• 2004

Thick-film photolithography is a new technology that combines lithography processes, such as exposure and development, with the conventional thick-film process applied to screen-printing. In this study, we developed a low-temperature cofireable silver paste applicable for thick-film processing to form fine lines using photolitho-graphic technologies. The optimum paste composition for forming fine lines was investigated. The effect of processing parameters, such as the exposing dose, had on the fine-line resolution was also investigated. As the result, we found that the type of polymer and monomer, the silver powder loading, and the amount of photoinitiator were the main factors affecting the resolution of the fine lines. The developed photoimageable silver paste was printed on a low-temperature cofireable green sheet, dried, exposed, developed in an aqueous process, laminated, and then fired. Our results demonstrate that thick-film fine lines having widths < 20 $\mu\textrm{m}$ can be obtained after cofiring.

• Proceedings of the Korea Contents Association Conference
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• 2008.05a
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• pp.630-634
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• 2008

The purpose of this research is to suggest improvement of web environment to supplement dependency of silver generation as we have aged super aged society ahead. In order to improve web environment for silver generation which has more various obstacles than common people, I examined methods to increase accessibility and usability through expansion of web interface by reinforcing contents structure and function. As a result, the try to increase web usability of web sites related to silver generation was positive, but interface designs are not unified which requires users to learn new skills, and developer produce designs that are not standardized. Therefore, I suggest web environment improvement methods to guide silver generation to be adapted to information society by suggesting solutions such as support for module of operation system and establishment of standardized design.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1325-1326
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• 2007

We have demonstrated new functionalities of Ag doped chalcogenide glasses based on their capabilities as solid electrolytes. Formation of such amorphous systems by the introduction of silver via photo-induced diffusion in thin chalcogenide films is considered. The influence of silver on the properties of the newly formed materials is regarded in terms of diffusion kinetics and Ag saturation is related to the composition of the hosting material. Silver saturated is related to the composition of the hosting material. Silver saturated Ge-Ch glasses have been used in the formation of solid electrolyte which is the active medium in programmable metallization cell (PMC) devices. This paper concerns our more recent work on silver-doped germanium selenide electrolytes and describes the electrical characteristics of PMC devices made from these materials following annealing at $300^{\circ}C$.

• The Korean Journal of Food And Nutrition
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• v.21 no.4
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• pp.583-591
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• 2008

The principal objective of this study was to assess the demands of the development program of silver health care professionals for elderly individuals residing in the Northern Gyeonggi-do area. To this end, a survey was conducted to investigate college students and employees related with elderly individuals in the area regarding their recognition, interest, and involvement in the labor training program. In the case of college students, the health education they had received was only 1 to 2 hours, from a school lecture(35%). The content of health education they desired was exercise(34%) and stress management skills(28%). The sources of health information they received included mass media(77%) and the internet(12%), and they trusted the information they received from health professionals(45%), and the mass media(34%). In the case of health professionals who were working at silver care facilities, the sources of health information to which they had access were mass media(51%), internet(14%), reliable health professionals(56%), mass media(22%), and books related to health (18%). The principal issues they reported as being relevant to the elderly were dementia(39%), hypertension(14%), arthritis (11%), and they reported that the most important personnel for elderly in the future would be care managers(44%), and care helpers(21%). 88% of subjects believed that there was a need for a silver welfare integrated information system. 43% of subjects used the internet, 77% of them required in-service training programs for the welfare of the elderly. Via this developmental program of silver health care professionals, a variety of new job opportunities can be provided in the future, and a program related to the silver service industry must be established as soon as possible.

• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.53.2-53.2
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• 2010

In this study, we focused on our specialized electrode process for Si back-contact crystalline solar cell. It is different from other well-known back-contact cell process for thermal aspect and specialized process. In general, aluminum makes ohmic contact to the Si wafer and acts as a back surface reflector. And, silver is used for low series resistance metal grid lines. Aluminum was sputtered onto back side of wafer. Next, silver is directly patterned on the wafer by screen printing. The sputtered aluminum was removed by wet etching process after rear silver electrode was formed. In this process, the silver paste must have good printability, electrical property and adhesion strength, before and after the aluminum etching process. Silver paste also needs low temperature firing characteristics to reduce the thermal budget. So it was seriously collected by the products of several company of regarding low temperature firing (below $250^{\circ}C$) and aluminum etching endurance. First of all, silver pastes for etching selectivity were selected to evaluate as low temperature firing condition, electrical properties and adhesive strength. Using the nano- and micron-sized silver paste, so called hybrid type, made low temperature firing. So we could minimize the thermal budget in metallization process. Also the adhesion property greatly depended on the composition of paste, especially added resin and inorganic additives. In this paper, we will show that the metallization process of back-contact solar cell was realized as optimized nano-paste characteristics.