• Journal of Microbiology and Biotechnology
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• v.22 no.4
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• pp.494-500
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• 2012

Silk fibroin (SF) peptide has been traditionally used as a treatment for flatulence, spasms, and phlegm. In this study, we examined whether SF peptide enhanced the anti-inflammatory effect of PEP-1-FK506 binding protein (PEP-1-FK506BP) through comparing the anti-inflammatory activities of SF peptide and/or PEP-1-FK506BP. In the presence or absence of SF peptide, transduction levels of PEP-1-FK506BP into HaCaT cells and mice skin and anti-inflammatory activities of PEP-1-FK506BP were identified by Western blot and histological analyses. SF peptide alone effectively reduced both mice ear edema and the elevated levels of cyclooxygenase-2, interleukin-6 and $-1{\beta}$, and tumor necrosis factor-${\alpha}$, showing similar anti-inflammatory effect to that of PEP-1-FK506BP. Furthermore, co-treatment with SF peptide and PEP-1-FK506BP exhibited more enhanced anti-inflammatory effects than the samples treated with SF peptides or PEP-1-FK506BP alone, suggesting the possibility that SF peptide and PEP-1-FK506BP might interact with each other. Moreover, the transduction data demonstrated that SF peptide did not affect the transduction of PEP-1-FK506BP into HaCaT cells and mice skin, indicating that the improvement of anti-inflammatory effect of PEP-1-FK506BP was not caused by enhanced transduction of PEP-1-FK506BP. Thus, these results suggest the possibility that co-treatment with SF peptide and PEP-1-FK506BP may be exploited as a useful therapy for various inflammation-related diseases.

• Journal of Korean Society for Atmospheric Environment
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• v.33 no.4
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• pp.370-376
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• 2017

This study was performed to investigate whether the decomposition process of $SF_6$ using an electron beam is economically reasonable when applied to the actual field. To do this, electron beam experiment and economic analysis were conducted. The experiment conditions are initial concentration of 1% of $SF_6$, 1 mA of input energy and 15 mA of flow rate with $H_2$ as an additive which were obtained from our previous research. As a result, removal efficiency of $SF_6$ was 90% for 8 hours continuously. In addition, economic analysis shows positive results in terms of using $SF_6$ decomposition process using electron beam. According to the analysis, the revenue is approximately 1.66 billion won in the first year and 3 billion won in the second year.

• Proceedings of the KIEE Conference
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• 2006.10a
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• pp.198-199
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• 2006

AC spark discharge voltage of SF6/C02and SF6/N2 containing various mixed rate in volume percent (1, 5 and 10%) of SF6 in non-uniform fields are investigated. The needle to plane electrode gap spacing was 5 and 10 mm, and the gas pressure was varied within the range of 0.1${\sim}$0.7 MPa. We have observed a N-characteristic typical for the electronegative gases even in gas mixtures of 1% SF6 with CO2 and N2 as buffer gases. Especially, the materials of the needle electrode affect the insulation properties of the gas mixtures drastically. On the contrary to the case of needle electrodes made by mild steel or high carbon steel, the N-characteristics are hardly perceived in the case of stainless steel needle in this experiment.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.58 no.4
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• pp.516-520
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• 2009

Atmosphere Plasmas of Gas Discharge (APGD) have been used in plasma sources for material processing such as etching, deposition, surface modification, etc. This study is to investigate and understand the fundamental plasma discharge properties. Especially, $SF_6/N_2$ mixed gas would be used in power transformer, GIS (Gas insulated switchgear) and so on. In this paper, we developed a one dimensional fluid simulation model with capacitively coupled plasma chamber at the atmosphere pressure (760 [Torr]). 38 kinds of $SF_6/N_2$ plasma particles which are an electron, two positive ions (${SF_5}^+$, ${N_2}^+$), five negative ions (${SF_6}^-$, ${SF_5}^-$, ${SF_4}^-$, ${F_2}^-$, ${F_1}^-$), thirty excitation and vibrational particles for $N_2$ were considered in this computation. The $N_2$ gases of 20%, 50%, 80% were mixed in $SF_6$ gas. As the amount of $N_2$ gas was increased, the properties of electro-negative plasma moved toward the electro-positive plasma.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.4
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• pp.635-640
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• 2008

New gas mixtures are now finding applications such as interrupting media for high-voltage circuit breakers. These mixtures consist of a high content of carbon tetrafluoride($CF_4$) added to sulfur hexafluoride($SF_6$). Nowdays $SF_6$ has been established for the use in gas insulated substations due to its high insulation withstand level and good arc quenching capability. At this paper Breakdown characteristics were investigated for $SF_6/CF_4$ mixtures when AC voltage and standard lightning impulse voltage(LI) was applied in a needle-plane electrodes. And partial discharge(PD) experiments were carried out in the test chamber which was made in needle-plane electrode. And ${\Phi}$-Q-N distribution of partial discharge signals was analyzed. The total pressure of the $SF_6/CF_4$ mixtures was varied within the range of 0.1-0.5 Mpa in the test chamber. The breakdown voltage in needle-plane electrode displayed N shape characteristics for increasing the content of $SF_6$ at positive impulse voltage and the PD inception voltage was increased slightly when pressure of $SF_6/CF_4$ Mixtures was increased. Maximum PD inception voltage is showed in 80% SF6/20%$CF_4$.

• Analytical Science and Technology
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• v.27 no.1
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• pp.27-33
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• 2014

This study described about preparation of the cross-linked silk fibroin (SF) film by ${\gamma}$-irradiation of the casted SF film, which is fabricated from aqueous solution regenerated via fibers of cocoons and their application as supports for human cell culture. The properties of cross-linked SF film were evaluated by FT-IR spectroscopy, contact angle, solubility to water, thermal analysis, surface area analyzer, and morphology via scanning electron microscopy (SEM). The cross-linked SF films were not dissolved in water and exhibited the rough surface morphology, large surface area, and good thermal properties. The human fibroblast cell (CCD-986sk) and embryo kidney-ft cell were well growed on the surface of cross-linked SF film supports prepared by ${\gamma}$-irradiation. The cross-linked SF film prepared by ${\gamma}$-irradiation can be used as biomaterials for human cell culture.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.58 no.1
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• pp.44-47
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• 2009

This paper describes the information for quantitative simulation of weakly ionized plasma. We must grasp the meaning of the plasma state condition to utilize engineering application and to understand materials of plasma state. $SF_6$ gas is widely used in industrial of insulation field. In this paper, $N_2$ is mixed to improve pure $SF_6$ gas characteristics. Electron transport coefficients in $SF_6-N_2$ mixture gases are simulated in range of E/N values from 70 to 400 [Td] at 300K and 1 Torr by using Boltzmann equation method. The results of this method. which are ionization coefficient, attachment coefficient, effective ionization coefficient, and critical E/N, can be important data to present characteristic of gas for insulation. Specially critical E/N is a data to evaluate insulation strength of a gas and is presented in this paper for various mixture ratios of $SF_6-N_2$ mixture gases.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.11 no.3
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• pp.203-207
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• 1998

After etching Al-Cu alloy films using $SiCl_4/Cl_2/He/CHF_3$ plasma, a corrosion phenomenon on the metal surface has been studied with XPS (X-ray photoelectron spectroscopy) and SEM (Scanning electron microscopy). In Al-Cu alloy system, the corrosion occurs rapidly on the etched surface by residual chlorine atoms. To prevent the corrosion, the $SF_6$ plasma treatment subsequent to the etch has been carried out. A passivation layer is formed by fluorine-related compounds on etched Al-Cu alloy surface after $SF_6$ treatment, and the layer suppresses effectively the corrosion on the surface as the RF power of $SF_6$ treatment increases. The corrosion could be suppressed successfully with $SF_6$ treatment in the RF power of 150watts.

• International Journal of Industrial Entomology and Biomaterials
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• v.5 no.2
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• pp.171-174
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• 2002

Two systemic fungicides, SF1 (Bavistin, a carbandazim fungicide 50% WP, Rallis India ltd., India) and SF2 (Bayleton 25% WP-Triadiamefon, a Triazole compound, Rallis India Ltd., India) were screened for control of muscardine disease in silkworm, Bombyx mori. One and two percent of SF1 and 0.05 and 0.1 % of SF2 in aqueous solution were found to be effective in in vivo condition for the control of the disease. These fungicides, on feeding through mulberry leaves continuously for two days to 4$^{th}$ and 5$^{th}$ instar silkworm larvae inoculated topically with conidia of Beauveria bassiana (4$\times$10$^{6}$ conidia/ml) resulted in reduction in mortality due to muscardine by over 90% as against 100% mortality in inoculated control. SF1 at 1% reduced the mortality by 90% in 4$^{th}$ instar and 91% in final instar silkworm while at 2%, the reduction was 92% and 96%, respectively. SF2 at 0.05 and 0.1 % concentration reduced the mortality by 82 and 88% during 4$^{th}$ instar and by 88 and 92% during 5$^{th}$ instar, respectively.

• The Bulletin of The Korean Astronomical Society
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• v.46 no.1
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• pp.55.1-55.1
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• 2021

Ram-pressure stripping (RPS) is known as a typical mechanism of quenching star formation (SF) of galaxies orbiting in clusters, but it can also boost the SF activity within a short period of time. Jellyfish galaxies, with eye-catching blue tails and knots, are such starburst galaxies undergoing strong RPS in galaxy clusters. Thus, they are very useful targets to understand their SF activity in relation to RPS. We study the SF activity of three jellyfish galaxies in massive clusters at z=0.3-0.4 (MACSJ1752-JFG2, MACSJ0916-JFG1, and A2744-F0083) with Gemini GMOS/IFU and compare our results to those of jellyfish galaxies in low-mass clusters. We obtain total star formation rates (SFRs) of up to 60 Mo/yr and SFRs in the tails of up to 15 Mo/yr, which are much higher than those of jellyfish galaxies in low-mass clusters with the median SFRs of 1.1 Mo/yr in total and 0.03 Mo/yr in tails. In addition, these SFRs are also significantly higher than the SF main sequence of galaxies at the redshifts of the three jellyfish galaxies. This implies that their SF activity is much more enhanced compared to jellyfish galaxies in low-mass clusters due to extreme RPS in massive clusters.