• Proceedings of the KIEE Conference
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• 1992.07b
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• pp.958-960
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• 1992

The fluorescence characteristics of near UV dye, BBQ pumped by Ar flashlamp have been studied for various electrical input energies applied to the flashlamp and argon fill pressures in the flash tube. The peak wavelength of fluorescence is about 380nm when the fluorescence intensity is at the peak value. The rise time of the fluorescence pulse is about 7 $\mu$sec and its FWHM is about 55$\mu$sec.

• Journal of Korean Society for Atmospheric Environment
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• v.16 no.5
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• pp.521-528
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• 2000

Photocatalyzed degradation of trace level trichloroethylene(TCE) and toluene in air was carried out over near UV illuminated titanium doxide(anatase) pellet in a flow reactor. The authors investigaed the effects of humidity and trace contaminant levels on the oxidation rates of toluene. Inlet concentrations of TCE and toluene were 10∼100ppm. TCE photooxidation was very rapid under what conditions, and almost 100% conversion was achieved for TCE(up to 70 ppm) as a single air contaminant. An important finding was that competitive adsorption between humidity and trace contaminants has a significant effect on the oxidation rate of what.

• Microbiology and Biotechnology Letters
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• v.22 no.2
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• pp.115-119
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• 1994

White mutant of Ganoderma lucidum(G4142) induced the non-basediocarpous basidiospores(NBB) from the aerial mycelia on agar media by the light illumination. Light was found to be necessary for NBB formation, but it also inhibited the growth of mycelium. The best sporulation was obtained at the periodic exposure of 16 hour light and 8 hour dark. Blue and yellow light were the most effective on sporulation, however, near UV and red light did not induce any spores. Effective light intensity for NBB bearing was about 1,000 lux as white light. Even after 16 days of culture, this strain did not form the pinhead nor chlamydospore. Optimum temperature for the mycelial growth and NBB formation were 30$\circ $C. Ganoderma lucidum G4142 exhibited the formation of stroma after five days of incubation at 30$\circ $C.

• Journal of Integrative Natural Science
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• v.4 no.3
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• pp.222-226
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• 2011

Cyclic AMP receptor protein(CRP) is involved in the activation of many genes corresponding to catabolite enzymes in Escherichia coli. In this study, mutant CRP(S128A) was used to elucidate the effect of Ser 128 on the cAMP-induced structural change. Based on the protease digestion and thermal analysis, serine 128 in CRP affects the cAMP binding capability and then structural change of CRP protein. In addition, CD spectra in near UV region revealed that S128A CRP retained the sensitive conformation to thermal effect relative to that of wild-type CRP, in spite of identical Tm values in the absence of cAMP.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.230-230
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• 2006

Density functional theory (DFT) calculations using the B3LYP hybrid functional and the 6-311++G(d,p) basis set have been performed to predict the wavelength dispersion of optical absorbance and refractive indices for organic compounds and polymers in the range between the vacuum UV (${\sim}157\;nm$) and near-IR (${\sim}850\;nm$). The DFT calculations can reproduce the experimental dispersions of absorbance and refractive indices with high accuracy and low costs. The calculated dispersions demonstrate that the judicious introductions of $-F\;and\;-CF_{3}$ into alicyclic and heterocyclic compounds are effective in reducing the absorption at shorter wavelengths. In addition, the calculated Abbe numbers that represent the refractive index dispersion in the visble region are linearly proportional to the calculated refractive indices at 589 nm.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.1
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• pp.37.1-37.1
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• 2012

We present mid-IR (MIR) and near-UV (NUV) properties of red sequence galaxies defined by optical color-magnitude relation. We use the Wide-field Infrared Survey Explorer (WISE) preliminary released data matched with the SDSS DR7/GALEX GR6. The red sequence galaxies with little emission lines show a wide spread of MIR (3.4um-12um) colors, implying a variety of MIR excess emission. We focus on the properties of the red sequence galaxies with MIR excess, comparing the properties of post-starburst galaxies to trace how galaxies migrate to the red sequence.

• Proceedings of the Optical Society of Korea Conference
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• 2000.02a
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• pp.238-239
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• 2000

The optical fibers are an interesting medium for effective tunable optical frequency conversion in the spectral range of UV, Visible, and near-IR through the nonlinear processes. A number of papers for developing the wideband and flat-gain amplifier for the WDM system applications through the combination of EDFA or thulium-doped fluoride fiber amplifier and Raman amplifier, are reported$^{(1)}$ . Even though a variety of papers related to Raman amplifications are published, the amplification with the feedback of the residual pump is not investigated yet. Accordingly, in this paper, we report the characteristics of forward Raman amplification by the simple and double-pass fiber Raman configuration through the feedback of residual pump beam. (omitted)

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.1733-1736
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• 2008

ZnO thin films with preferred orientation along the (0 0 2) plane were fabricated by a sol-gel method. The effects of the annealing temperature, time, and thickness were studied by investigating UV-visible spectra, FT-IR spectra, and XRD of ZnO films. The films were dried and annealed ed at $100^{\circ}C,\;200^{\circ}C$, and $300^{\circ}C$ for 1hr, 2hrs, and 3hrs, respectively. The film showed the preferred (0 0 2) orientation and high transmittance near 90% in the visible range. Also, SEM images of the films exhibited very smooth surfaces without holes and cracks. Schottky diodes were fabricated by using ZnO sol-gel material. Au and Al were used as electrodes to make Ohmic and Schottky contacts, respectively. The annealing temperature, time and the thickness dependent I-V characteristics were presented in this article.

• Journal of Information Display
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• v.10 no.4
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• pp.171-174
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• 2009

The optical and electrical properties of the amorphous indium gallium zinc oxide thin-film transistor ($\alpha$-IGZO TFT) were studied. When the $\alpha$-IGZO TFT was illuminated at a wavelength of 660 nm, the off-state drain current slightly increased, while below 550 nm it increased significantly. The $\alpha$-IGZO TFT was found to be extremely sensitive, with deep-level defects at approximately 2.25 eV near the midgap. After UV light illumination, a slight change occurred on the surface of the $\alpha$-IGZO films, such as in terms of the oxygen 1s spectra, resistivity, and carrier concentrations. It is believed that these results will provide information regarding the photo-induced behaviors in the $\alpha$-IGZO films.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.14 no.3
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• pp.246-250
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• 2001

ZnO thin films for light emission device have been deposited on sapphire and silicon substrates by pulsed laser deposition technique(PLD). A Nd:YAG laser was used with the wavelength of355 nm. In order to investigate the emission properties of ZnO thin films, Pl measurements with an Ar ion laser a light source using an excitation wavelength of 351 nm and a power of 100 mW are used. All spectra were taken at room temperature by using a grating spectrometer and a photomultiplier detector. ZnO exhibited Pl bands centers around 390, 510 and 640 nm, labeled near ultra-violet(UV), green and orange bands. Structural properties of ZnO thin films are analyzed with X-ray diffraction(XRD).