• Journal of the Korean Institute of Telematics and Electronics
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• v.27 no.9
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• pp.1419-1426
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• 1990

The microstructure and electrical conductivity characteristics were examined for the Yttria Stablized Zirconia that were added Titania with the concentration of 0.02wt%, 0.05wt% and 0.1wt%. The stabilized cubic phase had not been changed. The obtained density of the sintered body was higher than 97% of the theoretical density as the grain growth and proe removal. And the highest density of 5.91g/cm**3 was obtained for 0.02wt% addition of TiO2. When 0.02 wt% TiO2 was added to YSZ, the electrical conductivity was 0.293.(\ulcorner.cm)**-1 and the limit of electrolyte regime Pn was 4x10**-28 atm. at 1, 100\ulcorner, respectively. Those were improved value compared with the electrical conductivity 0.107 (\ulcorner.cm)**-1 and Pn 1.5x10**-27atm. without adding TiO2.

• Journal of the Korean Chemical Society
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• v.52 no.4
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• pp.387-393
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• 2008

• Journal of Welding and Joining
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• v.17 no.1
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• pp.116-123
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• 1999

The $CO_2$ welding with 100% $CO_2$ shielding gas is commonly used because of its cost and efficiency. Arc phenomena of the $CO_2$ welding is influenced by various factors such as chemical compositions of welding wire, shielding gas, welding condition and welding power source etc. In this study, arc phenomena is investigated by using two type of FCW(titania type, semi-metal type). Then, the welding quality and optimum welding condition can be selected. From this study, the following results were obtained; 1) In low current range(140A), FCW up to welding voltage(22V) resulted in a typical short circuit transfer. 2) In high current range(320A), the arc stability in titania FCW of a typical globular transfer is better than that of semi-metal FCW.

• Bulletin of the Society of Naval Architects of Korea
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• v.7 no.1
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• pp.45-56
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• 1970

The penetration of domestic high-titania potassium type arc welding rod has been investigated experimentally. The penetration of this type arc welding rod is influenced much more by changing welding current than welding speed and thickness of base metal in range of $6{\sim}9mm$. Values of penetrations were $1.00{\sim}1.75mm$ for $3.2mm{\phi}$ rod, and $1.10{\sim}1.86mm$ for $4mm{\phi}$ rod in adequate welding current range. The domestic rod's penetration is deeper than same type rod of the United State's product.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.10 no.1
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• pp.23-29
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• 2000

The agglomeration of titania particles with 30 nm in radii was simulated based on the colloidal stability. For surface potential increase from 4.5 to 16.8 mV the height of energy barrier increased. This tendency may explain the experimentally observed aggregation behavior where particles with smaller size and higher potential exhibited higher stability but form bigger and harder agglomerates with irregular shapes after drying.

• Environmental Engineering Research
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• v.10 no.1
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• pp.31-37
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• 2005

The selective catalytic experiments using both sulfated/sulfur-free titania and V2O5/TiO2 catalysts have been conducted for NO reduction by NH3 in a packed-bed, down-flow reactor. The sulfated and vanadia loaded titania exhibited higher activity for NO removal than the sulfur-free catalysts, where > 90% NO removal was achieved over the sulfated V2O5/TiO2 catalyst between 280∼500 C. The surface structure of vanadia species on the catalyst surface played a critical role in the high performance of catalysts in which the existence of monomeric/polymeric vanadate is revealed by Raman spectra studies. Water vapor and SO2 were added to the reacting system for the catalyst deactivation tests. At higher temperatures (T ≥ 350 C), little deactivation was observed over the sulfated V2O5/TiO2 catalysts, showing good durability against SO2 and water vapor, which is compared with deactivation at lower temperatures.

• Bulletin of the Korean Chemical Society
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• v.12 no.1
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• pp.17-22
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• 1991

Fourier transform infrared spectroscopy has been applied to the characterization of titania supported molybdena. The equilibrium adsorption method seemed to produce molybdena species homogeneously dispersed on the support. Even under an oxidizing environment, molybdena species appeared to be able to possess coordinatively unsaturated $Mo^{5+}$ ions owing to the natures of TiO$_2$, i.e. oxygen deficiency and permeability toward oxygen diffusion. At the initial stage of reduction, the terminal double bond oxygen ( Mo=O ) seemed to be removed, generating presumably $Mo^{4+}$. The carbonyl bands at 2198 and 2190 $cm^{-1}$ observed after CO exposure were attributed to the $Mo^{5+}{\cdots}CO\;and\;Mo^{4+}\;{\cdots}CO$ complexes, respectively, while the band pair at 2136 and 2076 $cm^{-1}$ to $Mo^{4+}(CO)_2$.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.05a
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• pp.193-194
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• 2021

Ti-salt agglomerated titanium dioxide photocatalyst from sludge, which has various and excellent functions such as nitrogen oxide removal performance, antifouling performance, and bacteria removal performance, is intended to be applied to UHPC. The UHPC used in this study is supposed to have a high compressive strength of 100~200MPa and a high flowability of 600mm or more with a slump flow. Titanium dioxide is fixed to the UHPC surface by sieving through a test sieve and compaction and painting using a vibration compactor, and this is tested according to ISO 22197-1. The NO removal amount is evaluated by classification the result range.

• Proceedings of the Korean Ceranic Society Conference
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• 2000.04a
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• pp.84.1-84.1
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• 2000

• Proceedings of the Korean Ceranic Society Conference
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• 2000.10a
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• pp.75.2-75
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• 2000