• Solar Energy
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• v.9 no.1
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• pp.14-21
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• 1989

Preparation of $TiO_2$ Film by the Dip-coating Method and its Application to photo-electrochemical Electrodes. $TiO_2$ film of n-type semiconductor has been of great interest as a material for solar energy conversion. For its practical application, the dip-coating method has been applied to prepare $TiO_2$ (anatase) film on the nesa glass substrate. Films up to about $1.8{\mu}m$ in thickness can be obtained by repeating the operation, dipping $\to$ pulling up $\to$ drying $\to$ heating at $500^{\circ}C$ for 10 minute. Heating temperature at $500^{\circ}C$ was adopted to convert $TiO_2$ gels into $TiO_2$ crystalline films. The $TiO_2$ films showed the maximum photocurrent ($14mA/cm^2$) at the film thickness of about $1.8{\mu}m$. It was also found that the additional heating at $500^{\circ}C$ for about 20 minutes improved remarkably the photo current of the $TiO_2$ films.

• The Plant Pathology Journal
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• v.19 no.3
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• pp.184-187
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• 2003

Verticillium wilt was first observed in 2001 on potatoes (Solanum tuberosum) cv. Superior at Daegwallyong area, one of the major seed potato producing areas in Korea. The wilted potato plants showed typical symptoms including gradual yellowing and interveinal necrosis. There was discoloration in the vascular tissues of the infected stems which turned light brown. Fungal isolates from discolored vascular tissues were whitish to creamy with folding on potato dextrose agar medium, where they used to produce resting dark mycelia but no micro-sclerotia. Conidiophores were septate with side branches, swelled at the base, and arranged in a whorl. Conidia were 2.5-11.2$\times$2.0-4.5 $\mu\textrm{m}$ um in size and were borne in small clusters at the tips of phialides. Optimal temperature range for mycelial growth was $25-30^{\circ}C$. Based on these cultural and morphological characteristics, the fungus was identified as Verticillium albo-atrum Reink & Berth. Pathogenicity tests by root dipping method revealed that the fungus caused the same symptoms as observed in naturally infected potato plants. This is the first report of Verticillium wilt on potato caused by Verticillium albo-atrum in Korea.

• Korean Journal of Materials Research
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• v.9 no.2
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• pp.181-187
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• 1999

In this study, the effect of residual stress on mechanical strength was investigated with 1 kind of whiteware body and 4 kinds of glazes which are produced in succeeding ceramic art place. Using dipping method, the body was coated for different times in order to manipulate the coating thickness and sintered in the different temperatures ($1200^{\circ}C$, $1250^{\circ}C$, $1300^{\circ}C$, $1350^{\circ}C$) for two thus hours. The sintered bodies were characterized by XRD, EPMA, FEM and UTM in order to study the forming of reaction layer between body and glazes, residual stresses and the effects of residual stresses on mechanical strength of pottery. At $1300{\circ}C$, we obtained maximum density and mechanical strength. By the finite element method, the residual stresses in surface of body were minimum in specific thickness of glazes and the mechanical strength of body in that thickness of glazes showed maximum when the firing temperature was settled.

• Textile Coloration and Finishing
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• v.20 no.4
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• pp.15-20
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• 2008

The cotton yarn was subjected to bio-polishing treatment with three commercial enzymes(Cellusoft L, Denimax-991L and Denimax-acid) to remove the fuzz on the cotton yarn. Also, enzyme treated cotton yarns were compared with singeing cotton yarns. Experimental variables of enzyme treated cotton yarn were as follow: concentration of enzyme solution and NaOH, dipping time, and processing temperature. The enzymatic treatments were evaluated by analyzing the effect on yarn count, twist contraction, evenness and tenacity. As the results, enzymatic treatment on cotton yarn induced same effects as the traditional singeing treatment. Also, silket treatment of cotton yarn after bio-polishing enhanced the tensile properties of the cotton yarn.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.8 no.4
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• pp.213-216
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• 1975

Yellow sea bream contains comparatively larger amount of fat among white muscle fishes, so that rancidity might easily occur during drying and storage. For the purpose of the protection of rancidity, the effect of some antioxidants was studied when yellow sea bream was sun-dried after dipping in the solutions and packed in PVC film$0.3mm\times12cm\times30cm $ for storage at room temperature. The inhibitory effect of additives was in order of Tenox-II, BHA, Sustane and NDGA, while EDTA, potassium sorbate, CTC and $\alpha-naphthylamine$ were ineffective. The results suggest that the treatment of $0.1\%$ Tenox-II solution and packing in PVC film is better condition to improve the quality of product and during drying and storage.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.3 no.2
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• pp.117-124
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• 1993

It was found that the basic principle of continuous crystal growth method was following as; the powder supplied from the feeding system is molten in the graphite crucible under the ambient gas. After forming the molten zone in the lower part of the crucible, the seed crystal is deeped into the melt and pulled down with the rotation so that the melt crystallized from the seed. When the lowering rate, rotation rate, feeding rate and temperature are correct, the single crystal can grow. The critical melt level, the feeding rate, the growth rate, the change of the shape of molten zone by the graphite susceptor and crucible, the position of work coil, the balance between the gravitational force of melt and the centrifugal force originated from the rotation of seed which are the variables of the crystal growth and the sintering phenomenon of melt surface were researched.

• Journal of Environmental Health Sciences
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• v.28 no.1
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• pp.41-49
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• 2002

Recently, pilot studies showed an evidence of reduction of airborne hexavalent chromium, Cr(VI), on PVC filter during air sampling and storage. However, the information on this in the field was limited. Thus, we studied the reduction behaviors of airborne Cr(VI) on PVC filters during sampling and storage at three field electroplating operations. Regression between sampling time and the reduction (ratio of Cr(VI) to total Cr concentrations) was not statistically significant (p>0.05). However, the reductions in samples collected for 240 ～ 340 minutes were significantly higher than those for 30 - 60 minutes. On the other hand, another experiment showed a good correlation (r=0.96) between sampling time and the reduction without an exceptional value. Storage temperature was not a factor affecting the reduction of Cr(VI) collected on PVC filter. The loss of Cr(VI) samples stored in alkali solution (2% NaOH/3% Na$_2$CO$_3$) was significantly lower than that stored in vial according to NIOSH method (p<0.05). Thus, dipping Cr(VI) samples into alkali solution was a storage method to minimize tile reduction.

• Textile Coloration and Finishing
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• v.15 no.3
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• pp.161-167
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• 2003

The preparations of deodorizing fibers using $TiO_2$ have been investigated. The fibers were coated with $TiO_2$ for the purpose of deodorizing by dipping fibers into the $TiO_2$ sol solutions and calcined at $450^\circ{C}$, $500^\circ{C}$ and $750^\circ{C}$ for 1 h after coating. The surface structure of the coated fibers was studied with XRD on the different preparation conditions of calcination temperatures. The deodorizing function of the prepared fibers was studied by the determination of the decomposing capability for $NH_3,\;CH_3SH\;and\;CH_3CHO$. The deodorant activity(D.A.) of these deodoriBing fibers was measured by chromogenic gas detector tubes. The deodorizing effect of the prepared fibers were shown to be similar for the three model compounds; 5wt% $TiO_2$ sol solution calcined at $450^\circ{C}$ < 5 wt% $TiO_2$ sol solution calcined at $500^\circ{C}$< 5 wt% TiO$_2$ sol solution calcined at $750^\circ{C}$.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.450-450
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• 2007

Indium tin oxide (ITO), which is used as an electrode in organic thin film transistors (OTFT), was modified with a self-assembled monolayer (SAM) by wet chemical surface modification. The surface of the ITO was treated by dipping method in a solution of 2-chloroethane phosphonic acid (2-CEPA) at room temperature. The work function in the ITO which was modified with the SAM in the 2-CEPA had 5.43eV. A surface energy and a transmittance were unchanged in an error range. On this study, therefore, possibility of ohmic contact is showed in the interface between the ITO and the organic semiconductors. These results suggest that the treatment of the ITO with the SAM can greatly enhance the performance of the OTFT.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.262-263
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• 2005

For mechanical and electrical stability and environment protection, Cu and stainless steel stabilizer is laminated to Ag layer to produce a composite neutral-axis(N-A) architecture in which the YBCO layer is centered between the oxide buffered metallic substrate and stabilizer strip lamination. this architecture allows the wire to meet operational requirements including stresses at cryogenic temperature, winding tensions, mechanical bending requirements thermal and electrical stability under fault conditions. we have experimentally studied mechanical properties of laminated stainless steel stabilizer on YBCO coated conductors. we have laminated YBCO coated conductors by continuous dipping soldering process. we have investigated lamination interface between solder and stabilizer, YBCO coated conductor. we evaluated bonding properties tensile / shear bonding strength, peeling strength laminated YBCO coated conductors.