• Journal of the Korean Crystal Growth and Crystal Technology
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• v.10 no.3
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• pp.271-277
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• 2000

Transparent $TiO_2$ thin films were prepared by the sol-gel method from titanium alkoxide aqueous solution containing large quantities of water. To prepare the aqueous system sol, the chelate compound solution were prepared from each 1 mole of titanium(IV)iso-propoxide, acetylacetone and 8 moles of isopropyl-alcohol. And then the 50 moles aqueous solution with the 0.02~0.50 moles of HCI for sol stability and the 0.3 mole of polyethylene glycol for coating adhesion were precisely dropped on the chelate compound solution. $TiO_2$thin films were fabricated by dip coating, drying and heat treatment at $400^{\circ}C$ and their characteristics were investigated by XRD, SEM and UV-visible spectrometer, The neutral sol of composition with TTIP : AcAc : IPA : $H_2O$ : PEG : HCl = 1 : 1 : 8 : 50 : 0.3 : 0.15 (molar ratio) was maintained stable sol condition and without problem for coating more than 30 days. The anatase phase $TiO_2$thin film prepared from 30 times dipping, drying and heat treating showed the flat surface and the fine microstructure of fracture surface with about 2 $\mu\textrm{m}$ thickness. Transparency of these $TiO_2$thin film was 80 % in the visible region.

• Korean Journal of Materials Research
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• v.9 no.8
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• pp.768-774
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• 1999

Yttia-doped ceria-stabilized ziconia polycrystals(Ce-TZP) was prepared by dipping method and its microstructure was investigated. By controlling doped-yttria content and annealing condition, yttria-doped Ce-TZP showed the microstructure with irregular grain shape and undulated grain boundary. Irregularity of grain shape increased with the amount of yttria doped, and severe undulated grain boundary was observed mainly at the surface region. In the case of yttria-doped Ce-TZP annealed at 1$650^{\circ}C$ for 2h after two dipping times into yttrium nitrate solution of 0.2M, it showed irregular grain shape both at the surface and at the interior region as well as the most severe irregularity. Hot pressed specimen had mean grain size of 0.3$\mu\textrm{m}$ and undulated grain boundary. All specimens with irregular grain shape were retained the tetragonal phase. The fracture toughness of yttria-doped Ce-TZP with irregular grain shape was over the value of 17.6MPa.m(sup)1/2.

• Korean Journal of Environmental Agriculture
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• v.37 no.3
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• pp.229-234
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• 2018

BACKGROUND: in vitro micronucleus test (vitMNT) is one of the promising alternative testing methods in genotoxicity test and was adopted as OECD test guideline for chemical registration. This study was conducted to optimize the cytoplasm conditions in vitMNT using Chinese hamster lung (CHL) cell. METHODS AND RESULTS: In this study cytokinesis-block micronucleus test was conducted. Mitomycin C and colchicine were used as positive control chemicals and were treated for three hours (short time) or twenty-four hours (long time). Giemsa solution was used for cell staining. For optimization of vitMNT, the final fixative was prepared as five concentrations (0%, 1%, 3%, 5%, and 25%) of acetic acid in methanol, and treatment times of the final fixative were varied under four conditions (immediately, one hour, four hours, and one day). CONCLUSION: Acetic acid at 1% in methanol as the final fixative was most adequate to preserve the cytoplasm around the nucleus in the interphase cells. Also, fixative treatment time of cell suspension for one to four hours may minimize the cell rupture. These results can be helpful for getting an accurate result promptly due to clear visual distinction to score micronucleus in vitMNT using giemsa solution.

• Tuberculosis and Respiratory Diseases
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• v.56 no.3
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• pp.261-268
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• 2004

Background : The resurgence of tuberculosis and outbreaks of multidrug resistant (MDR) tuberculosis have increased the emphasis for the development of new susceptibility testing of the Mycobacterium tuberculosis for the effective treatment and control of the disease. Conventional drug susceptibility testings, such as those using egg-based or agar-based media have some limits, such as the time required and difficulties in determining critical inhibitory concentrations, but these are still being used in many diagnostic laboratories because of no better lternatives, considering cost and accuracy. To overcome these limits, a rapid and simple method for new susceptibility testing, using live and dead assays, was applied for a bacterial cell viability assay to distinguish dead from live bacterial cells based on two-color fluorescence. Materials and Methods Strains : Forty strains were used in this study, 20 susceptible to all antituberculosis drugs and the other 20 resistant to the four first line antituberculosis drugs isoniazid, rifampicin, streptomycin and ethambutol. Antibiotics : The four antibiotics were dissolved in 7H9 broth to make the following solutions: $0.1{\mu}g\;isoniazid(INH)/m{\ell}$, $0.4{\mu}g\;rifampicin(RMP)/m{\ell}$, $4.0{\mu}g\;streptomycin(SM)/m{\ell}$ and $4.0{\mu}g\;ethambutol(EMB)/m{\ell}$. Results : Live and dead Mycobacterium tuberculosis cells fluoresced green and red with the acridin (Syto 9) and propidium treatments, respectively. These results are very well accorded with conventional drug susceptibility testing by proportional method on Lowensen-Jensen media (L-J) containing 4 drugs (INH, RMP, EMB and SM), showing a 93.7 % accordance rate in susceptible strains and 95% in resistant strains. Conclusion : The results of the drug susceptibility testing using the live and dead bacterial cell assay showed high accordance rates compared with the conventional proportion method on L-J. This finding suggests that the live and dead bacterial cell assay can be used as an alternative to conventional drug susceptibility testing for M. tuberculosis strains.

• The Journal of the Convergence on Culture Technology
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• v.5 no.3
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• pp.61-70
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• 2019

The painting group of Late Ming and Early Qing Dynasty is an era of confusion between the orthodox who faithfully cooperated with the Qing Dynasty and the individualist who had a hostile attitude. The country was ruined by these dynasties, and the family left the real world with the suffering of the breakdown and stayed in the mountains.Paldaesanin and Seokdo, the representative Yumin painters, did not form any a sect as a unique expression style for finding a true self.And, through his work, he expressed on madness and oddity through new ideas and composition that he feels misery and anger in his heart. The paintings of these paintings had semi-normative and impromptuous views of nature, which even the self burdened with grief was forgotten.And I expressed my own individuality and originality by forming a simple and free, on madness and oddity art aesthetic. The paintings of these paintings had semi-normative and impromptuous views of nature, which even the self burdened with grief was forgotten.And I expressed my own individuality and originality by forming a simple and free, on madness and oddity art aesthetic. Paldaesanin portrayed a strange figure with a spirit of resistance and a sad and angered emotion, through a unique technique of painting.The content is cynical, satirical, ironic, and on madness and oddity. On the other hand, Seokdo explained "ilhoeg" that the method of writing and the method of writing in "Hwaeolog" agree with each other.This has allowed us to achieve autonomy as a "rule without rules" that goes beyond the existing rules. And he delicately portrayed beauty, desire, and emotion with the use of sensuous brushes and the beauty of the colors.Their unique paintings were later conveyed to yangjupalgoe and led to the flow of paintings in the 18th century.