• The Journal of the Korean Society for Microbiology
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• v.22 no.3
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• pp.301-307
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• 1987

A total of 42 strains of Candida albicans were examined for susceptibility to three antifungal agents, amphotericin B(AMB), 5-fluorocytosine(5-FC), and ketoconazole(KTZ), using defined medium, synthetic amino acid medium-fungal(SAAM-F), supplemented yeast nitrogen base(SYNB) and undefined medium Sabouraud's dextrose broth(SDB) and Kimmig broth media. A tube dilution method was used with minimum inhibitory concentrations(MICs) determined after incubation for 24 hour and 48 hours. All testes were performed in duplicate. In general, MICs were more reproducible after 48 hour of incubation. Forthermore, MICs determined after incubation for 48 hours were significantly higher than those determined after 24 hours. The actural MICs obtained with the different antifungal agents were clearly influenced by the test medium used. The rank order of AMB MICs according to the test medium was as follows: SAAM-F>SYNB>SDB>Kimmig broth. With 5-FC, the following pattern was observed: SYNB>SAAM-F>SDB>Kimmig borth. For ketoconazole, the MICs according to the test medium was SAAM-F>SDB>SYNB> Kimmig broth. In amphotericin B, the MICs mean value with the test medium was as follows: SDB, 0.24 mcg/ml; Kimmig broth, 0.29 mcg/ml; SYNB, 0.21 mcg/ml and SAAM-F, 0.15mcg/ml. The actural value of 5-FC was; SDB, 37.20 mcg/ml; Kimmig broth, 67.41mcg/ml; SYNB, 21.29 mcg/ml and SAAM-F, 24.61 mcg/ml and in ketoconazole, the MICs value was; SDB, 1.83 mcg/ml; Kimmig broth, 4.08 mcg/ml; SYNB, 1.95 mcg/ml and SAAM-F, 1.41 mcg/ml. The results of this investigation suggested that broth dilution susceptibility testing of yeast and yeast-like fungi are best performed with an incubation period of 48 hours. Furthermore, medium composition can significantly influence the results of such testing.

• The Journal of Advanced Prosthodontics
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• v.13 no.2
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• pp.100-106
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• 2021

PURPOSE. The purpose of this study is to compare the antibacterial activity of currently purchasable denture cleansers against Candida albicans. Materials and methods: This study used tablet-type denture cleansers, PolidentⓇ, CoolingdentⓇ and FittydentⓇ, along with liquid denture cleansers, HexamedineⓇ, ListerineⓇ and Apple vinegarⓇ. The antibacterial activities of denture cleansers were evaluated based on the number of C. albicans and concentrations of the denture cleansers. Results. In the 0.5 × 106 cfu/㎖ culture medium, the C. albicans' death rate of PolidentⓇ was significantly lower than those of FittydentⓇ, HexamedineⓇ, ListerineⓇ, and Apple vinegarⓇ(P<.05). In the 0.5 × 107 cfu/, the C. albicans' death rates of PolidentⓇ and CoolingdentⓇ were significantly lower than those of FittydentⓇ, HexamedineⓇ, ListerineⓇ and Apple vinegarⓇ(P<.05). The C. albicans' death rates of PolidentⓇ and CoolingdentⓇ were significantly decreased at 0.02 g and 0.01 g. The C. albicans' death rate of FittydentⓇ was significantly decreased at 0.005 g (P<.05). The C. albicans' death rate of HexamedineⓇ was significantly decreased at 1/16 dilution. The C. albicans' death rate of ListerineⓇ was decreased at 1/8 dilution, and the antibacterial activity of Apple vinegarⓇ was decreased at 1/4 dilution (P<.05). Conclusion. As the number of C. albicans increased, the antibacterial activities of the denture cleansers decrease. In the tablet-type denture cleanser, all denture cleansers showed 100% C. albicans' death rate when used at a dose of 1 tablet. One denture cleanser showed the same antibacterial effect with only 1/3 of a tablet. In the liquid type denture cleanser, the level of dilution required was different for each denture cleanser.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.34 no.4
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• pp.246-250
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• 2021

TFTs technologies with as high mobility as possible is essential for high-performance large displays. TFTs using nanocrystalline silicon thin films can achieve higher mobility. In this work, the change of the crystalline volume fraction at different hydrogen dilution ratios was investigated by depositing nc-Si:H thin films using PECVD. It was observed that increasing hydrogen dilution ratio increased not only the crystalline volume fraction but also the crystallite size. The thin films with a high crystalline volume fraction (55%) and a low defect density (10¹⁷ cm^-3·eV^-1) were used as top gate TFTs channel layer, leading to a high mobility (55 cm²/V·s). We suggest that TFTs of high mobility to meet the need of display industries can be benefited by the formation of thin film with high crystalline volume fraction as well as low defect density as a channel layer.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.44 no.7
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• pp.603-610
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• 2016

This paper describes experimental results about emission and NOx reduction of dilution effect (Nitrogen and carbon dioxide) about various fuel compositions of synthetic natural gas (SNG). Combustion experiment was performed to investigate the combustion characteristics for SNG with various hydrogen ratio in SNG, heat input and equivalence ratio in a partially premixed model gas turbine combustor. NOx emission was similar to each hydrogen ratio and flame characteristics was investigated from OH chemiluminescence images. There was a singularity of CO emission in stoichiometric condition and it can be identified using OH chemiluminescence intensity. In addition, dilution effect was studied in using nitrogen and carbon dioxide as diluent to reduce the NOx emission. Carbon dioxide diluent was more effective to NOx reduction than nitrogen diluent because of its high diluent specific heat and its heat capacity.

• Proceedings of the KWS Conference
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• 2005.06a
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• pp.147-149
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• 2005

Effect of nitrogen content on SAW weld metal properties were investigated. Weld metal nitrogen content increased with an increase of base metal nitrogen content due to dilution. High nitrogen content in weld metal resulted in high free nitrogen content, and consequently reduced impact toughness due to, mainly, strain aging effect.

• 한국연소학회:학술대회논문집
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• 2014.11a
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• pp.73-74
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• 2014

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.03a
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• pp.98-98
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• 2003

비정질 실리콘 박막을 태양전지, 박막 트랜지스터, 이미지 센서, 컬러 디텍터 등에 적용하기 위한 많은 연구가 진행되고 있다. 이중 태양전지에 적용하기 위한 비정질 실리콘 박막은 p/i/n 다이오드 구조를 형성하게 되는데, 태양전지의 효율을 증가시키기 위해 결정질을 형성하거나 실리콘 화합물 박막을 적용한다. 본 연구에서는 비정질 태양전지의 흡수층(absorption layer)으로 사용되는 수소화된 비정질 박막의 결정화에 수소의 희석비가 미치는 영향을 파악하고자 하였다. PECVD 장비로 실란(SiH$_4$)과 수소(H$_2$) 가스를 이용하여 실리콘 박막을 증착하였고, 수소의 희석비(dilution ratio)를 변화시켜 비정질 실리콘 박막 내에 결정질 실리콘이 형성되는 정도를 관찰하였다. SEM과 Raman Spectroscopy를 이용해 박막의 두께 및 결정화도를 측정하였다. 실란에 대한 수소의 희석비가 증가할수록 증착률은 낮아지지만, 결정화도가 높아지는 것을 관찰할 수 있었다. 본 연구에서 형성한 결정질 실리콘 박막을 태양전지의 흡수층에 적용하면 효율 증가에 크게 기여할 것으로 판단된다.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.775-778
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• 2007

The present study numerically investigate the detailed structure of the syngas diffusion flames. In order to realistically represent the turbulence-chemistry interaction, the transient flamelet model has been applied to simulate the combustion processes and $NO_X$ formation in the syngas turbulent nonpremixed flames. The single mixture fraction formulation is extended to account for the effects of the secondary inlet mixture. Computations are the wide range of syngas compositions and oxidizer dilutions. Based on numerical results, the detailed discussion has been made for the effects of syngas composition and oxidizer dilution on the structure of the syngas-air and syngas-oxygen turbulent nonpremixed flames.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.8
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• pp.1104-1110
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• 2014

This paper investigates geometric effect of landmarks on three-dimensional navigation error in landmark-based vision navigation systems. Dilution of precision is derived for landmark measurement error on the focal plane of the camera and separately expressed in position DOP and attitude DOP. Values of DOP are observed for various configurations of landmarks.

• 한국연소학회:학술대회논문집
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• 2012.11a
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• pp.59-60
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• 2012

This paper describes gas turbine combustion characteristics of synthetic gas which is mainly composed of hydrogen and carbon monoxide. The combustion characteristics such as combustion instability, NOx and CO emission, temperatures at turbine inlet, liner and dump plane, and flame structure were investigated when changing when changing $H_2:CO$ ratio, dilution ratio, and $CH_4:syngas$ ratio. From the results, quantitative relationships are derived between key aspects of combustion performance, notably NOx emission. It is concluded that NOx emission of syngas is strongly influenced by the diluent heat capacity and combustion instability. Moreover, NOx control method using diluents such as $N_2$, $CO_2$, steam is verified.