• 한국분무공학회지
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• 제17권1호
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• pp.20-26
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• 2012

Inkjet printing is one of the direct writing technologies and is able to form a pattern onto substrate by dispensing droplets in desired position. Also, by inkjet technology manufacturing time and production costs can be reduced, and procedures can be more efficient. To form a metal pattern, it must be harmonized with conductive nano ink, printing process, sintering, and surface treatment. In this study, micro patterning of conductive line has been investigated using the piezoelectric printhead driven by a bipolar voltage signal is used to dispense $20-40{\mu}m$ diameter droplets and silver nano ink which consists of 50 nm silver particles. In addition, hydrophobic treatment of surface, overlap printing techniques, and sintering conditions with changing temperature and times to achieve higher conductivity.

• 한국전문물리치료학회지
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• 제2권2호
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• pp.66-72
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• 1995

The purpose of this study was to determine a more effective method for shoulder pain reduction. Forty-five normal subjects were randomly assigned to one of 3 groups a control group, an acupuncture-like transcutaneous electrical nerve stimulation(ALTENS) group, and a silver spike point(SSP) group. Each person in the ALTENS and SSP groups was measured for pressure pain threshold before and after a 20 minute treatment. The control group was also checked for pressure pain threshold before and after a 20 minute period but no "treatment" was given. The major findings were as follows ; 1)The ALTENS and SSP groups showed significant differences before and after treatment but the control group showed no significant difference. 2)When the three groups were compared, the only significant difference was between the SSP group and the control group. As mentioned above, it may be concluded that both ALTENS and SSP therapy were effective in reducing shoulder pain when measured directly after treatment. However, SSP did not show any superior effect. Further study should be done to determine the effective the maintained pain reduction with post-treatment time lapse.

• 대한의생명과학회지
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• 제24권1호
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• pp.30-34
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• 2018

Silver (Ag) has been widely used in commercial products and medical fields since ancient times because of its antibacterial effect. It is harmless and non-toxic to the human body. For this reason, recent research has actively evaluated antimicrobial activity using silver (Ag). In this study, we investigated the inhibitory effect of a silver-based compound, silver phosphate ($Ag_3PO_4$) on the growth of Staphylococcus aureus and the activation of human immunity. First, the inhibitory effect of $Ag_3PO_4$ on the growth of Staphylococcus aureus was confirmed by a growth curve and a colonyounting method. As a result, the growth inhibitory effect increased as the concentration of $Ag_3PO_4$ increased. Specifically, treatment with $5{\mu}g/mL$ of $Ag_3PO_4$ resulted in no bacteria growth, and the colony-counting method showed a remarkable inhibition. In addition, the expression of cytokine IL-8 by $Ag_3PO_4$ was examined to investigate the cellular immune system activation by $Ag_3PO_4$. After pretreatment of Staphylococcus aureus for 1 hour with $50{\mu}g/mL$ $Ag_3PO_4$, an increased IL-8 mRNA expression resulted. In cells treated with $Ag_3PO_4$, we found that the expression of IL-8 was enhanced in a time-dependent fashion compared to non-treated cells. These results indicate that $Ag_3PO_4$ induces antimicrobial activity against Staphylococcus aureus and activates human immunity. These results are expected to contribute to the future study of the mechanism of silver (Ag) and silver-based compounds in relation to antibacterial activity.

• 한국의류산업학회지
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• 제6권6호
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• pp.810-814
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• 2004

This study is one of the fundamental researches for the development of future smart clothing and textile products using silver(Ag) nano powder. Our study was focused on the blocking or insulating effects of nano-processed textiles from electromagnetic waves. Also, for the surveying of the actual effect to human body, we measure the variation of electroencephalogram which is an indication of human physical symptoms. Among various textiles in this experiment, nano silver processed case has shown the best blocking performance from the electromagnetic waves, which decreases depending on the distance. As a reference model of working environment, we setup the visual stimuli object on the computer that is a source of electromagnetic wave. The power spectrum distribution and the incidence of electroencephalogram was measured. The analysed data has shown that, with nano-processed textiles, ${\beta}$ wave does not appear very often where ${\beta}$ wave appears only to illustrate the stable states of human's body. However, as for the materials without nano processing, the ratio of ${\gamma}$ waves in the total level of electroencephalogram becomes higher in spite of short exposure to visual stimuli in work environment, which shows that the worker becomes stressed. The ${\beta}$ wave electroencephalogram of all materials is drawn in calcarine fissure of occipital lobe to show the convergent distribution, and stronger with block-processed Nano Silver Silk(NSS). The study based on the potential risks of human diseases such as physical fatigue by electromagnetic waves, and has shown that the application of Nano Silver textile for human uses require a proper particle size of it which would not penetrate cellular tissues, and a proper binder and binding treatment for it. However, it is highly required for back-up researches to verify various aspects in applying nano silver to textile products.

• 한국임상수의학회지
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• 제30권3호
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• pp.172-177
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• 2013

본 연구는 개 외이염에 대한 enrofloxacin-silver sulfadiazine (Baytril$^{(R)}$ otic, Bayer, USA)의 치료효과를 평가하는 것이다. 24두의 외이염 이환견을 대상으로 처치군에는 바이트릴 오틱을, 대조군에는 증류수를 이도내 7일간 국소투약한 후 7일후에 임상증상, 미생물 및 효모균수를 통해 효과를 비교하였다. 또한 외이염에서 분리된 세균 및 효모균에 대한 바이트릴 오틱의 최소억제농도를 산출하였다. 주요 분리균으로는 Staphylococcus pseudintermedius, Pseudomonas aeruginosa, Proteus spp and Malassezia pachydermatis.이었다. 임상증상의 경감은 81%, 미생물수는 87% 감소하였다. 바이트릴 오틱은 분리된 균에 대한 살균효과가 충분하였고 국소투약에 대한 부작용은 관찰되지 않았다. 따라서 바이트릴 오틱은 개의 외이염 감염에 대한 효과적이며 안전한 제제로 판단된다.

• Carbon letters
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• 제3권1호
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• pp.13-16
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• 2002

The modification of coal-tar pitch has been carried out by heat treatment of pitch at different temperatures in the range ($300^{\circ}-400^{\circ}C$) for different times (2-5 hrs) in air and nitrogen. The pitch heat treated in air at lower temperature ($300^{\circ}C$) exhibit increase in softening point by $20^{\circ}C$ as compared to only $2^{\circ}C$ when treated in nitrogen. The changes are faster in air than in pure nitrogen. Pitch as such as well as after heat treatment were further treated with metal complexes by solution route. Silver intake has been found to increase from 0.5 to 0.8 % in nitrogen treated pitch while the uptake is found to decrease for pitches treated in air at $350^{\circ}C$ for 5 hrs. Experiments have also been made to incorporate silver into PAN and PAN-ox fibers through solution route. The metal intake has been found to be more in PAN-ox fibers than in PAN as such. Metal loaded carbon composites have been made by using metal loaded fibers as well as cokes. These composites as such exhibit higher surface oxygen complexes but decrease after activation.

• Restorative Dentistry and Endodontics
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• 제46권3호
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• pp.38.1-38.13
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• 2021

The elimination of endodontic biofilms and the maintenance of a leak-proof canal filling are key aspects of successful root canal treatment. Several materials have been introduced to treat endodontic disease, although treatment success is limited by the features of the biomaterials used. Silver nanoparticles (AgNPs) have been increasingly considered in dental applications, especially endodontics, due to their high antimicrobial activity. For the present study, an electronic search was conducted using MEDLINE (PubMed), the Cochrane Central Register of Controlled Trials (CENTRAL), Google Scholar, and EMBASE. This review provides insights into the unique characteristics of AgNPs, including their chemical, physical, and antimicrobial properties; limitations; and potential uses. Various studies involving different application methods of AgNPs were carefully examined. Based on previous clinical studies, the synthesis, means of obtaining, usage conditions, and potential cytotoxicity of AgNPs were evaluated. The findings indicate that AgNPs are effective antimicrobial agents for the elimination of endodontic biofilms.

• 한국표면공학회지
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• 제14권4호
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• pp.209-214
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• 1981

Electrolytic recovery of gold and silver from diluted solutions has at first been applied nearly 100 years ago. Compared with other recovery techniques electrolytic treatment offers several advantages. But to achieve high space-time yields special constructions of electrolytic cells for improved mass transfer are necessary. Ex-tended cathode surface areas and vigorous agitation are important features. Gold and silver recovery by use of newly developed electrolytic cell constructions - rotating tubular bed reactor and impact rod reactor - has been described. Calculations based on industrial application during several years are confirming that electrolytic recovery of precious metalss from diluted solutions has been operated in a very economic way.

• 한국식품영양학회지
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• 제27권5호
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• pp.805-816
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• 2014

We investigated the quality characteristics and resulting sensory evaluation of semi-dried silver pomfret treated with high hydrostatic pressure (HHP) processing and brining for 14 days at 4 and $10^{\circ}C$ to evaluate the effects of treatment with HHP processing. HHP treatment and brining could cause compaction of fibers and the space between muscle. The G' values of all samples were higher than the G" values and the tan ${\delta}$ values of the tissue ranged from 0.222 to 0.251 with no further changes observed during storage. HHP treatment and brining significantly increased the total color difference, and the HHP and brine-treated group scored significantly higher than the others in terms of sensory evaluation. HHP treatment combined with brining could have a significant effect on the quality characteristics of the semi-dried products and their storage stability, and it is suggested from the results that they may have the potential to satisfy the requirements to produce commercially marketable food grade products.

• 한국표면공학회지
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• 제41권1호
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• pp.33-37
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• 2008

Polycarbonate has a high transmittance to light, low specific gravity, flexibility and cost-effectiveness that extends the application field of the polymer to bio-engineering, optics, electronic parts, etc. Moreover, electro plating of metallic film on PC could endow the parts the electromagnetic interference shielding capability. However, poor adhesion of copper on PC limited the wide usage in the industry. In this work, a composite(PC/ABS) and MmSH(Momentary mold Surface Heating) injection process were used to improve the plating characteristics; plating thickness, gloss and adhesion. Also plasma treatment and chemical treatment were employed for improving adhesion. Plating characteristics on PC/ABS were better than those on PC due to the anchoring effect of butadiene. MmSH injection process could ameliorate the gloss and coating adhesion. Also plating thickness and adhesion of PC and PC/ABS were increased by plasma treatment.