• Korean Journal of Microbiology
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• v.28 no.4
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• pp.345-350
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• 1990

In order to ferment D-xylose directly to ethanol, Yeasts capable of utilizing D-xylose as a sole carbon source and energy source were isolated from soil, sawdust and rotten woods. Among them, the yeast strain, which showed the best ability to produce ethanol, was identified as Candida sp. L-16 isolated from rotten woods. The optimal conditions for production of ethanol were 60rpm of agitation speed, 28j.deg.C of temperature, 4.5 of initial pH and 5% of D-xylose concentration. Ethanol production was reached to maximum state for 4 days culture. Under these optimal conditions, the maximum ethanol concentration and theoretical ethanol yield were 2.4%(v/v) and 74.4% of theoretical value, respectively.

• Korean Journal of Materials Research
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• v.27 no.5
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• pp.242-247
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• 2017

ZnO film was prepared on a p-type Si wafer and then annealed at various temperatures in air and vacuum conditions to research the electrical properties and bonding structures during the annealing processes. ZnO film annealed in atmosphere formed a crystal structure owing to the suppression of oxygen vacancies: however, ZnO annealed in vacuum had an amorphous structure after annealing because of the increment of the content of oxygen vacancies. Schottky contact was observed for the ZnO annealed in an air. O 1s spectra with amorphous structure was found to have a value of 529 eV; that with a crystal structure was found to have a value of 531.5 eV. However, it was observed in these results that the correlation between the electronic characteristics and the bonding structures was weak.

• Textile Coloration and Finishing
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• v.22 no.1
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• pp.21-27
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• 2010

The purpose of this research was to investigate the color characteristic and the dyeing properties of Glycyrrhizae Radix extract on cotton fabrics. The highest absorbance of Glycyrrhizae Radix extract was obtained in 75 v/v% of ethyl alcohol in water. Pre-mordanted cotton fabrics dyed at $30^{\circ}C$ and pH 3 for 80 minutes showed the highest K/S value. According to the dyeing conditions, the colors of the fabrics varied from yellow(Y) and yellowish red(YR) to greenish yellow(GY). The color fastness of the fabrics in dry-cleaning and water was 4~5 rating. The deodorization capacity and UV-cut effect of the dyed fabrics were higher than those of undyed ones.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.1157-1166
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• 2008

Critical surcharge value of silt ground polluted with garbage leachate to the dyes $q_{cr}=3.73c_u$ and ultimate bearing capacity value $q_{ult}=8.60c_u$. Lateral flow pressure at polluted silt ground was about $P_{max}$/3 and depth of maximum lateral flow pressure was found at that of H/3 of soft layer thickness(H). Expression of polluted silt ground of fracture baseline at stability control charge by Matsuo Kawamura is $S_v=3.56\exp\{0.51(Y_m/S_v)\}$.

• Journal of the Semiconductor & Display Technology
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• v.4 no.2 s.11
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• pp.1-5
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• 2005

Electon spin resonance measurements have been performed on the Mg-doped wurtzite GaN thin films grown on sapphire substrates by low-pressure metal-organic chemical vapor deposition. The sample set included films as-grown with the regular Mg doped and Mg delta doped samples and the corresponding annealed ones. The resonance signal has been observed from the annealed Mg delta-doped sample with the Lande g value of 2.029. This indicates that the singlet resonance signal originates from the neutral Mg acceptor located at 0.24 eV above the valence band edge and 0.13 eV above the Fermi level because of the nuclear hyperfine spin 1=0 of Mg and the larger value than the free electron g=2.0023.

• Journal of the Korean Chemical Society
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• v.66 no.5
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• pp.341-348
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• 2022

In this work, radio frequency magnetron sputtering was used to deposit zinc selenide thin films on p-type silicon (100) wafers and glass substrates in a high vacuum chamber. Several surface characterization instruments were implemented to study the thin films. X-ray photoelectron spectroscopy results revealed that oxidized Zn bound to Se (Zn-Se) at 1022.7 ± 0.1 eV becomes the dominant oxidized species when Se concentration exceeds 70%. Scanning electron microscopy coupled with energy dispersive spectroscopy showed that incorporating Se in Zn thin films will lead to formation of ZnSe grains on the surface. Contact angle measurements indicated that ZnSe-60 exhibited the lowest total surface free energy value of 24.94 mN/m. Lastly, ultraviolet-visible spectrophotometry and ultraviolet photoelectron spectroscopy data evinced that the energy band gap gradually increases with increasing Se concentration with ZnSe-70 having the highest work function value of 4.91 eV.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.15 no.6
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• pp.239-243
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• 2005

The effect of pH and particle size on the dispersion stability of ultra-fine $BaTiO_3$ suspensions in aqueous medium have been investigated by means of zeta potential, sediment experiments, and powder properties (particle analysis, specific surface area) etc. Zeta potential as a function of pH for two particles of different size increases from -75 to +10 mV with decreasing pH from 8.5 to 1.4. The curve of zeta potential for small particle (150 nm) has slow slope than that of large particle (900nm), giving IEP (isoelectric point) value of pH=1.6 for small particle and pH=1.9 for large particle respectively, which means that it is more difficult to control zeta potential with pH fur small particle than large particle. The dispersion stability of $BaTiO_3$ particles in aqueous medium was found to be strongly related with the agglomeration of colloidal suspensions with time through the sedimentation behaviors of colloidal particles with time and pH value.

• Journal of the military operations research society of Korea
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• v.5 no.1
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• pp.123-135
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• 1979

Weapon System effectiveness indices are a key factor to the cost-effectiveness analysis in the process of allocating national resources in an optimal fashion. First part of this paper reviews the need of weapon -effectiveness indices, historical development of methodologies on military strength evaluation with various models of indices, and the interrelation-ship between weapon effectiveness indices and war-game. Second part of this paper analyzes the concepts and usage of the already developed methodologies, i .e., index of power, weapon lethality index (W.L.I.), index of fire power potential (I.F.P), fire power potential (F. P. P), and weapon effectiveness indices/weighted unit value (W. E. I/W. U. V.). Finally, weaknesses and limits of these methodologies are compared and evaluated. Result of this research shows that the W. L. I, I. F. P, and F. P. P seem to possess many non-scientific or ambiguous facets, but the W. E. I/W. U. V method produces more detailed, inclusive, and reasonable indices. The paper concludes with the emphasis on the importance of the provision of the theoretical bases to develop effectiveness indices which can be used to evaluate Korean weapon systems, and the early establishment of a specialized research group to manage and develop methodologies on the weapon effectiveness indices.

• Transactions on Electrical and Electronic Materials
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• v.9 no.2
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• pp.67-72
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• 2008

Al-doped p-type ZnO thin films were fabricated by RF magnetron sputtering on n-Si (100) and homo-buffer layers in pure oxygen ambient. ZnO ceramic mixed with 2 wt% $Al_2O_3$ was selected as a sputtering target. XRD spectra show that the Al-doped ZnO thin films have ZnO crystal structure. Hall Effect experiments with Van der Pauw configuration show that p-type carrier concentrations are arranged from $1.66{\times}10^{16}$ to $4.04{\times}10^{18}\;cm^{-2}$, mobilities from 0.194 to $198\;cm^2V{-1}s^{-1}$ and resistivities from 0.0963 to $18.4\;{\Omega}cm$. FESEM cross section images of different parts of a p-type ZnO:Al thin film annealed at $800^{\circ}C$ show a compact structure. Measurement for same sample shows that density is $5.40\;cm^{-3}$ which is smaller than theoretically calculated value of $5.67\;cm^{-3}$. Photoluminescence (PL) spectra at 10 K show a shoulder peak of p-type ZnO film at about 3.117 eV which is ascribed to electron transition from donor level to acceptor level (DAP).

• Journal of the Korean Applied Science and Technology
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• v.8 no.2
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• pp.153-159
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• 1991

The electrochemical oxidation of p-methoxyphenol and hydroquinone for wastewater treatment application was investigated on platinum anode. At the cyclic voltammetry, it was observed that nagative shift of peak potential of p-methoxyphenol and hydroqinone as the pH of electrolytes increases and the peak current showed higher at strong electrolytes than weak electrolytes. In the case of p-methoxyphenol, the optimum electrode potential of controlled potential electrolysis was observed at the potential region of 0.8-1.0 (V vs. SCE) and hydroquinone was showed at the potential of l.0(V vs. SCE). Specially the oxidation rate of p-methoxyphenol and hydroquinone was showed high value in the acid electrolytes.