• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2015.11a
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• pp.196-197
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• 2015

ZnSe의 전기화학적 거동은 각각 다른 pH를 갖는 전해질에서의 linear sweep voltammogram 분석에 의해 체계적으로 고찰되었다. 제어된 조성을 갖는 칼코지나이드 ZnSe 박막이 complexing agent의 역할을 하는 citrate를 포함한 알카리 용액에서 전해 증착되었다. 다른 pH의 전해질에서 증착된 ZnSe 박막의 형상을 분석하고, 추가적으로 다른 pH의 전해질 및 어닐링 온도 변화에 따른 ZnSe 박막의 XRD분석이 이루어졌다.

• Journal of Sericultural and Entomological Science
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• v.41 no.3
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• pp.201-204
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• 1999

The silk/paper mulberry paper was prepared by recycling of the hard twisted silk waste and its mechanical properties was investigated. The silk waste was pretreated with sodium hydroxide(0.5%) and sodium carbonate(4%) to make it easy for beating and fibrillation. The silk/paper mulberry hand sheet paper has better mechanical properties of tearing strength and air permeability compared with the traditional and modified traditional paper. Treating with alkaline solution, the hard twisted silk waste could be used for an novel composite material.

• YAKHAK HOEJI
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• v.16 no.4
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• pp.155-161
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• 1972

The hydrolysis of phenobarbital is decelerated in alkaline solution by betacyclodextrin. The betacyclodextrin inhibits the degradation of phenobarbital up to 1.5 fold in the system containing 1% betacyclodextrin. The degradation mechanism in systems containing betacyclodextrin is the same that in system without complexing agent, although the rate constants are different. The pH dependence of the hydrolysis rate deceleration is compared with the ionization percent of betacyclodextrin. The results indicate that a direct relationship does not exist between the ionization of betacyclodextrin. It seems reasonable therefore that the phenobarbital undergoes a stable complex with betacyclodextrin and complex formation would provide a better shield for the phenobarbital from hydroxyl ion attack.

• Textile Coloration and Finishing
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• v.22 no.3
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• pp.207-213
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• 2010

Natural dyeing of Sangju silk for graveclothes with mulberry extract solution was studied. The anthocyanidin dye in the extracted mulberry solution was markedly influenced by pH condition, which resulted in the changed maximum light absorption from a $\lambda$max of 525nm in acidic condition to 380nm in alkaline condition possibly due to the irreversible transformation of anthocyanidin to cyanidin form of the dye. The color fastness properties to both light and washing were good when the fabrics were dyed at $80^{\circ}C$ with the mulberry-extracted solution upto twice extraction.

• Journal of the Korean Ceramic Society
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• v.12 no.1
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• pp.16-22
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• 1975

The network structure of a glass is known to be cracked by a chemical reaction, diffusion, and ion exchange of alkali ion, formed at the crack tip of the glass surface, when water is present on the glass surface. Since the durability of glass is reduced, due to the fatigue phenomenon mentioned above, pollution problem of glass goods, especially bottle glass, is becoming acute gradually. A static fatigue phenomenon was studied thermodynamically in this paper, and a mechanism of static fatigue, a quality control, and a method of preventing pollution for the main local glass goods were also investigated. The PH of reacted solution and the quantity of extracted alkali were measured at different conditions such as temperature, reacting time, particle size of a crushed glass sample, and the nature of reacting solution. The enthalpy change was calculated from the Arrhenius equation. The results are given below; 1) The absolute value of enthalpy change for the bottle glass was found to be higher than the for the flat glass. 2) The fatigue phenomenon of a glass was more sensitive to the temperature than to the reacting time. 3) The durability of glass in acid solution is stronger than in alkaline solution. 4) The substance which cracks the network structure of glas is considered the hydroxyl ion.

• Journal of Microbiology and Biotechnology
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• v.8 no.2
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• pp.178-181
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• 1998

An exopolysaccharide, designated as A49-Pol, was produced from Bacillus polymyxa KCTC 8648P in nitrogen sufficient conditions. The viscosity of the culture broth increased up to $2\times10^4$cP in 38 hours of culture and then decreased to $1.5\times10^4$CP at 48 hours. The $1.0\%$ (w/v) solution of purified A49-Pol represented pseudoplasticity with a viscosity of $2.7\times10^4$cP which was two times higher than xanthan at the same concentration. The viscosity of the A49-Pol solution was also greatly affected by its concentration in comparison with the xanthan solution. The viscosity of $1.0\%$ A49-Pol solution was 930-fold higher than its $0.2\%$ solution, whereas the corresponding viscosities of xanthan solution experienced only l7-fold difference. The viscosity was observed to be maximum at pH 7.0 in both A49-Pol and xanthan solutions, and gradually decreased as the pHs of the polysaccharide solutions went to acidic or alkaline regions. The viscosity of A49-Pol solution was very sensitive to temperature compared to xanthan and decreased with increasing temperature. The viscosity of $0.6\%$ solution of A49-Pol was 8,100 cP at $10^{\circ}C$ and 55 cP at $50^{\circ}C$. The viscosity was also affected by the presence of surfactants such as Span 20 and Triton X-l00 ; with $0.5\%$ Triton X-l00 (v/v), the viscosity of A49-Pol solution increased by $50\%$.

• Journal of agricultural medicine and community health
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• v.21 no.2
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• pp.159-171
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• 1996

It is investigated to determine the removal efficiency of organic - phosphorus insecticide residues in lettuce by washing processes, the 5 washing solution (stagnant tap water, flowing tap water, alkaline solution, acidic solution) were used with the washing time(10, 30, 50sec) and frequencies(1, 2, 3 washing, 2 rinsing). The removal efficiency of residual pesticides by 5 washing methods was increased on the more washing time and frequency, and also was the highest on the 3 times washing for each 50 sec. The removal rate with stagnant tap water was 33.7% of Diazinon, 45.7% of Dimethoate and 24.6% of Fenitrothion, but 29.4% of Diazinon, 37.7% of Dimethoate and 24.5% of Fenitrothion with flowing tap water. Therefore, the former was significantly higher effective than the latter one. The removal rate of residual pesticides with alkaline solution showed 32.1% of Diazinon, 49.5% of Dimethoate and 29.9% of Fenitrothion, and 30.4% of Diazinon, 36.4% of Dimethoate and 21.0% of Fenitrothion with acidic solution. The washing efficiency of neutral detergent showed the most effective result than others with 47.1% of Diazinon, 58.0% of Dimethoate and 39.5% of Fenitrothion. Consequently, it's appeared that the neural detergent washing was the most effective method on the 3 times washing for each 50 sec.

• Current Research on Agriculture and Life Sciences
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• v.5
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• pp.33-39
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• 1987

In order to study the degradation pattern of propanil in solution, the environmental factors such as temperature, pH and UV irradiation effect on propanil degradation were investigated. The degradation of propanil in solution was more rapid in high temperature than in low. The production amount of DCA was increased in high temperature, and then was decreased in a certain period of time because of conversion to TCAB, but the concentration of TCAB was maintained without more degradation. Propanil was rapidly hydrolyzed in alkaline solution as well as in strong acidic solution. Degradation product, DCA was rapidly produced and condensed to TCAB in strong acidic and alkaline condition. On exposur to ultraviolet light, 90% of original propanil was degraded within 20minutes, 0.3 ppm of DCA was produced in 10 minutes, and maintained the concentration throughout irradiation times.

• Journal of Information Display
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• v.6 no.2
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• pp.19-24
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• 2005

The density controlled carbon nanotubes (CNTs) are grown on the iron acetate nanoparticles by using the freeze-dry method. The iron-acetate [Fe(II)$(CH_3COO)_2$] solution is used to prepare the catalytic iron nanoparticles. The density of CNTs is controlled in order to enhance the field emission process. Furthermore, the patterning of the iron nanoparticle catalyst-layer for the fabrication of electronic devices is simply achieved by using alkaline solution, TMAH (tetramethylammonium hydroxide). We applied this patterning process of catalyst layer to form the electron emitter with under-gate type triode structure.

• Journal of Advanced Marine Engineering and Technology
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• v.29 no.1
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• pp.107-115
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• 2005

The effects on the formation of anodic oxide films on Mg-Al alloy (AZ91) in 1M-NaOH solution was investigated using parameters of current density and time during anodizing The general tendency has been confirmed that the increase of anodizing time improves the corrosion resistance. It is considered that the formation of anodic oxide film was increased by increasing the applied current and the anodizing time to generate active dissolution reaction In anodizing at constant current density. passivity potentials shifted to noble direction with increasing current densities. It was confirmed that oxygen quantify in anodic oxide films increased with anodizing time. The compact films above 4 $mA/cm^2$ were formed with the shape of an island in grooves at early stage and then grew with combination of the islands