• Journal of Power System Engineering
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• v.20 no.1
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• pp.30-35
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• 2016

The objective of this study is to investigate the physicochemical properties of the catalysts and the feasibility of remanufacturing them after removing ash in CDPF using a cleaning agent KOH. Compared with the carbon oxidation ability of fresh CDPF, that of de-ashed CDPF had an insignificant difference due to the low activation energy of CO and $CO_2$. As ash deposited in CDPF was de-ashed with KOH, it had a practical feasibility on remanufacturing point of view, but washcoat was melted about 26%. Further studies were required for the prevention of washcoat loss.

• Journal of the Korean Magnetic Resonance Society
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• v.14 no.1
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• pp.9-17
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• 2010

The water proton relaxation rates increase linearly with concentrations of contrast agents, and could be expressed as a function of the concentrations. In this paper, we have investigated MR properties of two different contrast agents, $GdCl_3$ and $CoCl_2$. Relaxivity coefficients were calculated from individual contrast agent solutions, and used for predicting relaxation rates at mixtures of two contrast agents. From the experimental results, we have discussed the feasibility of constructing water solutions with the desired relaxation times using specific mixtures of contrast agents.

• Journal of Powder Materials
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• v.17 no.5
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• pp.409-414
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• 2010

Titanium dioxide ($TiO_2$), which is one of the most basic materials in our daily life, plays a key role for environment purification. We synthesized $TiO_2$ nanoparticles by the hydrolysis reactions of titanium tetraisopropoxide using $HNO_3$ as a peptizing agent or $CH_3COOH$ as a chelating agent in the sol-gel method. The powder consisted of a rod shape or a spherical shape according to the concentration and kind of acid. The physical properties of $TiO_2$ nanoparticles were investigated with X-ray diffraction, SEM, BET analysis, and UV-Vis spectrophotometer.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.11a
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• pp.9-14
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• 2006

Deinking is a series of unit operations designed to detach ink from cellulose fibers and separate the dispersed ink from the pulp slurry. Deinking chemicals are process aids that enable expensive mill equipment used in these unit operations to operate more efficiently. This paper presents an overview of ONP deinking efficiency with cellulolytic enzymes and synthetic collector in low alkalinity process. The deinking efficiency of old news print even in low alkalinity condition was enhanced with enzyme contained complex agent. The brightness of deinked pulp was increased with less residual ink particles and yield of deinked pulp was improved compared to the deinked pulp of conventional alkaline method.

• International Journal of Railway
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• v.6 no.3
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• pp.90-94
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• 2013

Cement or lime is generally used to improve the strength of soil. However, bacteria were utilized to produce cementation of loose soils in this study. The microo rganism called Bacillus, and $CaCl_2$ was introduced into loose sand and soft silt and $CaCO_3$ in the voids of soil particles were produced, leading to cementation of soil particles. In this study, loose sand and soft silt typically encountered in Korea were bio-treated with 3 types of bacteria concentration. The cementation (or calcite precipitation) in the soil particles induced by the high concentration bacteria treatment was investigated at 7 days after curing. Based on the results of Scanning Electron Microscope (SEM) tests and EDX analyses, high concentration bacteria treatment for loose sand was observed to produce noticeable amount of $CaCO_3$, implying a significant cementation of soil particles. It was observed that higher calcium carbonate depositions were observed in poorly graded distribution as compared to well graded distribution. In addition, effectiveness of biogrouting has also been found to be feasible by bio-treatment without any cementing agent.

• Journal of the Korean institute of surface engineering
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• v.55 no.5
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• pp.299-307
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• 2022

Gold plating is used as a coating of connector in printed circuit boards, ceramic integrated circuit packages, semiconductor devices and so on, because the film has excellent electric conductivity, solderability and chemical properties such as durability to acid and other chemicals. In most cases, internal connection between device and package and external terminals for connecting packaging and printed circuit board are electroless Ni-P plating followed by immersion Au plating (ENIG) to ensure connection reliability. The deposition behavior and film properties of electroless Au plating are affected by P content, grain size and mixed impurity components in the electroless Ni-P alloy film used as the underlayer plating. In this study, the correlation between electroless nickel plating used as a underlayer layer and cyanide-free electroless Au plating using thiomalic acid as a complexing agent and aminoethanethiol as a reducing agent was investigated.

• Journal of Microbiology and Biotechnology
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• v.1 no.3
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• pp.163-168
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• 1991

A new angiogenesis inhibitor, FR-118487 was obtained by chemical modification of FR-111142 which was isolated from the fermentation products of Scolecobasidium arenarium F-2015. The antiangiogenic activity of FR-118487 was compared with that of the parent compound, FR-111142. In the endothelial cell proliferation test in vitro and the angiogenesis in the chick embryo chorioal-lantoic membrane assay, FR-118487 had about 5∼10 times stronger antiangiogenic activities than FR-111142. In addition, FR-118487 inhibited the angiogenesis in the rabbit corneal assay and suppressed the solid tumor growth in mice. These findings showed that FR-118487 would be a unique antiangiogenic agent with promising antitumor activity.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 2000.04a
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• pp.13-20
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• 2000

• Proceedings of the Korean Nuclear Society Conference
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• 2002.05a
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• pp.321.1-321
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• 2002

• Proceedings of the PSK Conference
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• 2000.10a
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• pp.277.2-277.2
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• 2000