• 한국염색가공학회지
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• 제21권2호
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• pp.14-21
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• 2009

In this article, silk fabric was treated with silver nitrate ($AgNO_3$) as oxidizing agent, with conditions such as concentration, and treating time, and subsequently treated with reducing agents such as sodium boron hydride ($NaBH_4$) and sodium sulfide ($Na_2S$) to obtain cathodic coloration. After coloration of silk fabric, dyeing properties (K/S value), colorfastnesses such as wash, rubbing and light, and antibacterial activity property were examined. $AgNO_3$ treating time and reducing time did not influence K/S value, whereas the pH value at alkaline region showed a high K/S value of silk fabric. The cathodic colorations of silk fabric with both of reducing agents at $30^{\circ}C$ have excellent color fastnesses. Also the high antibacterial activities were obtained by the treatment with silver nitrate even at 1% of lower concentration.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회A
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• pp.1553-1555
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• 2008

Super-hydrophobic treated Polyimide film was used as a flexible substrate for developing a new method of metallization. Hydrophilic patterns were fabricated by IN irradiation through shadow mask. Patterned super-hydrophobic substrate was dipped into a bath containing silver nano ink Silver ink was only coated on hydrophilic patterned area. Metal lines of $600{\mu}m$ pitch were fabricated successfully. However, their thickness was too thin to serve as interconnection. To overcome this problem, iterative dipping was conducted. After repeating five times, the thickness of silver metal lines were increased to over than $2{\mu}$. After heat treatment of silver lines, their resistivities were reduced to order of $30{\mu}{\Omega}$-cm the similar level of values reported in other literatures. So, a new method of metallization has high potential for application of RFID antenna and flexible electronics substrates.

• 한국재료학회지
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• 제22권10호
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• pp.562-568
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• 2012

Metal nanowires can be coated on various substrates to create transparent conducting films that can potentially replace the dominant transparent conductor, indium tin oxide, in displays, solar cells, organic light-emitting diodes, and electrochromic windows. One issue with these metal nanowire based transparent conductive films is that the resistance between the nanowires is still high because of their low aspect ratio. Here, we demonstrate high-performance transparent conductive films with silver nanofiber networks synthesized by a low-cost and scalable electrospinning process followed by two-step sequential thermal treatments. First, the PVP/$AgNO_3$ precursor nanofibers, which have an average diameter of 208 nm and are several thousands of micrometers in length, were synthesized by the electrospinning process. The thermal behavior and the phase and morphology evolution in the thermal treatment processes were systematically investigated to determine the thermal treatment atmosphere and temperature. PVP/$AgNO_3$ nanofibers were transformed stepwise into PVP/Ag and Ag nanofibers by two-step sequential thermal treatments (i.e., $150^{\circ}C$ in $H_2$ for 0.5 h and $300^{\circ}C$ in Ar for 3 h); however, the fibrous shape was perfectly maintained. The silver nanofibers have ultrahigh aspect ratios of up to 10000 and a small average diameter of 142 nm; they also have fused crossing points with ultra-low junction resistances, which result in high transmittance at low sheet resistance.

• 미생물학회지
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• 제37권4호
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• pp.273-276
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• 2001

본 연구에서는 중금속, 특히 은(銀)을 축적하는 세균을 지하수로부터 분리, 동정하고, 분리 균주의 특성 및 중금속 축적조건을 규명하여 최대축적이 일어날 수 있는 조건을 검토하였다. 서울시 지하수 10개 정점으로부터 분리된 은(銀) 축적 세균 중 가장 축적능이 뛰어난 두 균주를 선별하였으며 이들은 Pseudomonas fluorescens와 Bacillus cereus로 동정되었다. 본 분리 균주는 은(銀)의 농도가 5 ppm, 10 ppm, 20 ppm으로 높아질수록 생장 저해를 심하게 받았다. pH가 낮을수록 세포의 성장이 저하되기는 하였지만 세포 당 은(銀) 축적율은 오히려 증가하였으며 24시간 이내에 최대축적이 이루어졌다. 이때 은(銀) 축적량은 Pseudomonas fluorescens의 경우 약 1.9 $mg/g{\cdot}cell$ 이었으며 Bacillus cereus는 약 1.65 $mg/g{\cdot}cell$ 이었다. 은(銀) 처리시, Bacillus cereus에서 126 KDa, 89 KDa, 25 KDa 등 3개의 단백질이 특이적으로 증가하였으며, Pseudomonas fluorescens에서는 101 KDa, 68 KDa, 27 KDa 크기의 단백질이 감소하였으나 34 KDa 크기의 새로운 단백질이 유도됨을 확인하였다.

• 보존과학회지
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• 제30권2호
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• pp.157-168
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• 2014

본 연구는 행정박물 보존 처리에서 자주 사용되고 있는 금속 광택제 중 3 종 (Polish T, H, C)을 선정하여 은표면의 황색 변색층을 효과적으로 제거함과 동시에 표면의 손상을 최소화하며, 광택제에 함유된 변색 억제 성분 (tarnish inhibitor)의 성능을 비교하여 보존성이 가장 우수한 광택제를 알아보고자 하였다. 실험 결과, 광택제 C를 사용하여 면봉 및 린트-프리 와이프로 세정한 시편들이 균일한 표면의 표출과 최소의 손상을 가져온다는 결과를 얻었으며 부식층 제거에도 뛰어난 결과를 보임을 확인할 수 있었다. 또한 광택제 처리 후 변색 억제 필름이 형성 되어도 변색 현상을 완벽히 방지할 수 없지만 그 중에서도 광택제 C가 자외선과 황변에 가장 안정한 것으로 나타났다. 접촉각 측정 결과에서도 소수성 및 분산 성질이 광택제 T와 광택제 H보다 상대적으로 우수한 특성을 보였다. 본 실험을 통해 현재 은제 행정박물 보존 처리에 사용되는 광택제 중에서 광택제 C가 황변 및 표면 특성이 가장 우수한 성능을 보임을 확인할 수 있었다.

• 한국결정성장학회지
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• 제25권3호
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• pp.93-97
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• 2015

본 연구에서는 고순도 균질 마이크로 Ag 입자를 얻기 위하여 용매추출법과 RF-LPP법을 이용하여 Air 분위기에서 $500^{\circ}C$에서 3시간 동안 열처리하여 Ag 입자를 합성하였다. 합성된 마이크로 Ag 입자를 XRD에 의해 비교 분석한 결과 주요 peak들이 JCPDS card(No. 87-0719)와 일치하는 것을 확인하였다. RF-LPP법을 이용함으로써, 핵 생성 싸이트 제어를 통해 균질 마이크로 Ag 입자를 합성하였으며, 환원처리 후 산소의 함유가 줄어드는 것을 확인하였다. 본 연구를 통하여 재활용 기술에 큰 기여를 할 것이라 기대한다.

• 한국광학회지
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• 제34권6호
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• pp.283-288
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• 2023

본 연구에서는 quartz, sapphire, slide glass와 같이 투명한 기판 위에 (3-mercaptopropyl) trimethoxysilane (MPTMS)를 처리하고 나노미터 두께로 은을 증착하여 형성된 은 나노 박막의 광학적, 전기적 특성을 탐구한다. 기판의 MPTMS 증착에 따라 각각 5, 7, 9, 13 nm 두께를 갖는 은 나노 박막의 표면 형태 변화를 전자현미경을 통해 확인하고, UV-visible 전자기파 영역의 투과 측정 실험을 통해 금속 나노 박막에서 나타나는 국소 표면 플라즈몬에 의한 흡수 효과가 줄어드는 것을 확인하였다. 이는 MPTMS에 의해 나노미터 두께의 금속 박막이 균일하게 형성된 것을 의미한다. 또한 MPTMS 증착 시간을 30분부터 77시간까지 조절함으로써 UV-visible 투과율과 전기전도도 변화를 측정하여 균일한 금속 나노 박막 형성을 위한 MPTMS의 증착 조건에 대해 탐구한다. 본 연구 결과는 투명 기판 위 균일한 금속 나노 박막 형성에 대한 연구 및 고성능 나노 박막 전극 개발 등과 같은 응용 분야에 도움이 될 것이다.

• 한국약용작물학회지
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• 제16권6호
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• pp.416-420
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• 2008

This study was conducted to investigate the influence of shading material on the chlorophyll fluorescence, photosynthesis, transpiration, stomatal conductance and its any correlations in Panax ginseng C.A.Meyer. Fo was higher in polyethylene shade net than in silver-coated shading plate, but this treatment caused a lower Fm in comparison with silver-coated shading plate. Also, Fv/Fm and PhiPS2 showed higher in silver-coated shading plate than in polyethylene shade net. The relationship between net photosynthetic rate and transpiration, stomatal conductance were increased as the PAR (Photosynthetic active radiation) was increased and reached maximum at the $200-400\;{\mu}mol/m^{2}/s$ of PAR in all of leaves, and the higher in silver-coated shading plate than in polyethylene shade net. A linear equation was obtained between net photosynthetic rate and transpiration, net photosynthetic rate and stomatal conductance. SPAD was higher in silver-coated shading plate than in polyethylene shade net.

• 한국표면공학회지
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• 제49권1호
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• pp.87-91
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• 2016

The development of high performance transparent electrode with flexibility have been required for flexible electronics. Here, we demonstrate the silver nanowire and reduced graphene oxide hybrid transparent electrode for replacing brittle indium-tin-oxide electrode by spray coating technique and plasma reduction. The spray coating system is applied to deposit silver nanowire and over coated graphene oxide films and it has a great potential to scale-up. The resistance of silver nanowire transparent electrode is reduced by 10% and the surface roughness is decreased after graphene oxide coating. The over-coated graphene oxide is successfully reduced by $H_2$ plasma treatment and it is effective in increasing the environmental stability of electrode. The lifetime of silver nanowire and reduced graphene oxide hybrid electrode at $85^{\circ}C$ of Celsius degree of temperature and 85% of relative humidity has much increased.

• 한국환경농학회지
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• 제38권3호
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• pp.124-132
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• 2019

BACKGROUND: Silver grass (Miscanthus sinensis) No. 1 was developed for production of bio-ethanol, and for the purpose the silver grass growing sector was established in Geumgang basin, Iksan, Jeonbuk, in 2011. However, the other application potentials except for using as the bio-energy resources should be considered because of the drop in international oil prices. Therefore, there is the necessity of a scientific basis to use the silver grass instead of rice straw as the organic matter source that is used for improvement of soil quality in the plastic film house. METHODS AND RESULTS: The silver grass was applied at 5, 10, 15 and 20 Mg/ha and tilled before the watermelon was planted in the plastic film-house. The control plot was treated with 10 Mg/ha with rice straw, and watermelons have been cultivated for 3 years(2017~2019). Soil aggregation, soil chemistry, and the growth characteristics were investigated, when the watermelon was harvested every year. Soil aggregation levels at the 2nd and 3rd year of watermelon harvest were similar from the plot applied with the silver grass at 5 Mg/ha and the control plot, and increased in the silver grass treated plots with more than 10 Mg/ha. However, there was no statistically significant difference between the plots. The nitrogen mineralization of silver grass in the control plot tended to be similar to the 5 Mg/ha plot, but the silver grass treated plots with over 10 Mg/ha showed low nitrogen mineralization. Soil EC on harvest stage was proportional to the applied mass of the silver grass, but pH was in inverse with the applied mass. Soil organic matter content, available phosphate, and exchangeable cations increased with the continued use of silver grass. Watermelon weight found to be the best on more than 15 Mg/ha of silver grass, and the sugar content was highest when 10 Mg/ha was treated. CONCLUSION: The use of the silver grass at 10 Mg/ha annually as the organic source was effective in replacing rice straw while growing fruits and vegetables on the plastic film house.