• Bulletin of the Korean Chemical Society
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• 제26권10호
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• pp.1575-1578
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• 2005

• Bulletin of the Korean Chemical Society
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• 제27권1호
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• pp.150-152
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• 2006

• 한국표면공학회지
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• 제19권3호
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• pp.92-108
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• 1986

An electroplating on the lead frame fabricated from domestic copper plate was studied experimentally. In this study, nickel was plated on the thin copper lead frame and silver layer was coated on the nickel film in the cyanide electrolyte. The effect of process variables such as current density, plating time, coating thickness and flow rate of electrolytic solution on the properties of coating was investigated. Some samples on each step were fabricated during electroplating. The results obtained from polarization measurement, observation of SEM photograph, adhesion test of coating and microhardness test are as follows. On silver plating, polarization resistance of potentiostatic cathodic polarization curve is reduced as the flow rate of Ag electrolytic solution increases. And above resistance is also reduced when the minor chemicals of sodium cyanide and sodium carbonate are added in potassium silver cyanide bath. The reduced polarization resistance makes silver deposition on the cathode easy. An increase in the current density and the coating thickness causes the particle size of deposit to coarsen, and consequently the Knoop microhardness of the coating decreases. On selective plating an increase in the flow rate of plating solution lead to do high speed plating with high current density. In this case, the surface morphology of deposit is of fine microstructure with high Knoop hardness. An increasing trend of the adhesion of coating was shown with increasing the current density and flow rate of electrolytic solution.

• 대한의용생체공학회:의공학회지
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• 제43권4호
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• pp.219-229
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• 2022

In this study, we propose a miniaturized micro-ceramic heater device. After screen-printing a silver paste between pre-sintered two aluminum oxide plates to integrate a heating circuit, the device was fabricated through a low-temperature sintering process. In order to configure the optimal heating circuit integration condition, the output current evaluation and heating test were performed according to the number of screen prints of the silver paste at various voltages. A silver paste-based heating circuit printed with a line width of 200 ㎛ and a thickness of 60 ㎛ was successfully integrated on a pre-sintered alumina substrate through a low-temperature sintering process. In the case of the 5 times printed device, the thermal response showed a response rate of 18.19 ℃/sec. To demonstrate feasibility of the proposed device in the medical field, such as bio-tissue suturing and hemostasis, a voltage was applied to pig tissue in the device to test tissue change due to heat generated from the device. These results show the possibility that the proposed small ceramic heater could be used in the medical field based on its excellent temperature response.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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• pp.547-547
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• 2012

As displays become larger and solar cells become cheaper, there is an increasing need for low-cost transparent electrodes. Intensive effort has been made to replace ITO (Indium Tin Oxide) based transparent electrode with cheap and flexible ones. Among those, silver nanowires have got limelight because of its great conductivity and flexibility. Even though the electric property of the Ag nanowire based transparent electrode surpassed ITO, the optical property needs to be improved (lower transmittance, higher haze). Here, we reported transparent electrode based on Ag nanowires and conducting polymer to improve optical properties. The Ag nanowires are coated onto PET films and the resulting transparent electrode film shows $200ohm/{\Box}$ resistance and > 90% optical transmittance.

• Environmental Engineering Research
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• 제15권1호
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• pp.23-27
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• 2010

Genotoxic- and ecotoxic assessments of silver nanoparticles (AgNPs) were conducted on the freshwater crustacean Daphnia magna. AgNPs may have genotoxic effects on D. magna, given that the DNA strand breaks increased when exposed to this nanoparticle. Increased mortality was concomitantly observed with DNA damage in the AgNPs-exposed D. magna, which suggests AgNPs-induced DNA damage might provoke higher-level consequences. The results of the comparative toxicities of AgNPs and Ag ions suggest that AgNPs are slightly more toxic than Ag ions. Overall, these results suggest that AgNPs may be genotoxic toward D. magna, which may contribute to the knowledge relating to the aquatic toxicity of AgNPs on aquatic ecosystems, for which little data are available.

• 한국임상수의학회지
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• 제27권3호
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• pp.252-256
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• 2010

소 유방염은 주로 세균 감염에 의한 유선조직에 염증이 생기는 질병으로 유방염의 치료와 억제를 위해서는 1차적으로 세균을 사멸시키는데 있다. 본 연구에서는 소 유방염의 원인이 되는 다양한 세균들에 대한 은 이온의 항균효과와 적용 농도를 측정하였다. 유방염 원인균에 대한 은 이온의 최소 억제 농도 (minimal inhibitory concentrations, MICs)와 최소 살균 농도 (minimum bactericidal concentrations, MBCs)를 측정하였으며, 주사전자현미경 (scanning electron microscopy, SEM)을 이용하여 은 이온에 의한 세균의 형태 변화를 확인하였다. 다양한 유방염 원인균에 대한은 이온의 최소 억제 농도와 최소 살균 농도는 1.9에서 15.6 ${\mu}g$/ml로 세균에 따라 차이가 보였으며, 은이온 처리 후 주사전자현미경 촬영 결과 Staphylococcus aureus와 Escherichia coli의 세포벽이 함몰되거나 파괴되는 것을 볼 수 있었다. 이러한 결과는 유방염 원인이 되는 다양한 원인균에 대해 은이온의 살균 효과와 그 적용 농도를 보여주는 것으로, 소 유방염의 치료와 방어를 위한 임상적인 적용 가능성을 보여주는 것이다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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• pp.260-261
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• 2005

$YBa_2Cu_3O_{7-\delta}$ superconductor films have been prepared on silver substrates by electrophoretic deposition. As silver does not react with $YBa_2Cu_3O_{7-\delta}$ compound and has little influence on its superconductivity, it is usually doped in $YBa_2Cu_3O_7$ to improve the strength of the material and eliminate micro-cracks. It has been proved that Ag additive can lower the melting temperature of $YBa_2Cu_3O_{7-\delta}$ and act as linking bridge among $YBa_2Cu_3O_{7-\delta}$ particles, thus in this paper Ag doped $YBa_2Cu_3O_{7-\delta}$ thick films are prepared by electrophoretic co-deposition. As there are only some referenced experience formula and models for co-electrophoretic deposition and does not exist unified explanation, the behavior of Ag particles during co-electrophoretic deposition is also studied.

• Journal of Genetic Medicine
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• 제17권2호
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• pp.83-88
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• 2020

Silver-Russell syndrome (SRS) is a rare genetic disorder characterized by intrauterine growth restriction, poor postnatal growth, relative macrocephaly, a triangular face, body asymmetry, and feeding difficulties. It is primarily diagnosed according to a clinical scoring system; however, the clinical diagnosis is confirmed with molecular testing, and the disease is stratified into the specific molecular subtypes. SRS is a genetically heterogeneous condition. The major molecular changes are hypomethylation of imprinting control region 1 in 11p15.5 and maternal uniparental disomy of chromosome 7 (UPD(7)mat). Therefore, first-line molecular testing should include methylation-specific approaches for these regions. Here, we report an extremely low birth weight (ELBW) infant with intrauterine growth retardation, postnatal growth retardation, and dysmorphic facial appearance-characteristics consistent with the clinical diagnostic criteria of SRS. Methylation-specific molecular genetic analysis revealed UPD(7)mat, while the loss of heterozygosity was not detected on chromosomal microarray analysis. We present a case of SRS with suspected uniparental heterodisomy of chromosome 7 in an ELBW infant.

• 대한치과보철학회지
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• 제37권3호
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• pp.293-300
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• 1999

The purpose of this study was to evaluate the in vitro antifungal effect of several kinds of denture lining materials containing nystatin and silver-zeolite on Candida albicans. Three commercially available tissue conditioners (Soft-Liner, Coe-Comfort, Coe-Soft) and two direct denture relining materials (Tokuso Rebase, Durabase) were selected. In terms of the zone of inhibition and some basic physical properties, I could find the following results ; 1. Nystatin or silver-zeolite included in those relining materials had definite antifungal activities against the Candida albicans. 2. As times went on, both of the antifungal agents's activities decreased gradually. 3. Antifungal agents did not affect the relining materials' basic physical properties. 4 Direct chairside relining materials showed unfavorable dark discoloration with response to silver-zeolite.