• Bulletin of the Korean Chemical Society
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• v.26 no.10
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• pp.1582-1584
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• 2005

• Polymer Science and Technology
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• v.8 no.3
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• pp.293-297
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• 1997

• Proceedings of the Materials Research Society of Korea Conference
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• 2008.05a
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• pp.17.2-17.2
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• 2008

• Proceedings of the Korean Magnestics Society Conference
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• 2008.12a
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• pp.234.1-234.1
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• 2008

• Korean Journal of Materials Research
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• v.14 no.8
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• pp.587-594
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• 2004

Three-dimensionally ordered macroporous (3DOM) structures of the $LiCoO_2$ electrode materials for Li secondary batteries were fabricated by using the close-packed arrays of PMMA spheres served as templates. In order to successfully fabricate the cathode materials with highly ordered array form, the metal citrates were applied to new precursors. The precursor/template composites were prepared by the infiltration with metal citrate precursors into the voids of template. By removing the PMMA templates, then, the inverse opal structures with the uniform pores of narrow size distribution were resulted. It was confirmed that the 3DOM $LiCoO_2$ material is to take a single phase of rocksalt (R3m) structure. In addition, 3DOM $LiNiO_2$ and $LiMn_{2}O_4$ cathode materials were fabricated using an identical preparation procedure. Also, the morphology of the 3DOM cathode materials calcined at $500^{\circ}C\;to\;700^{\circ}C$ was observed by scanning electron microscope.

• Journal of the Korean Ceramic Society
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• v.50 no.1
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• pp.31-36
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• 2013

${\beta}$-SiC powders were synthesized by a carbothermal reduction process using $SiO_2$-C precursors fabricated by a sol-gel process using phenol resin and TEOS as starting materials for carbon and Si sources, respectively. The C/Si molar ratio was selected as an important parameter for synthesizing SiC powders using a sol-gel process, and the effects of the C/Si molar ratio (1.4-3.0) on the particle size, particle size distribution, and yield of the synthesized ${\beta}$-SiC powders were investigated. It was found that (1) the particle size of the synthesized ${\beta}$-SiC powders decreased with an increase in the C/Si molar ratio in the $SiO_2$-C hybrid precursors, (2) the particle size distribution widened with an increase in the C/Si molar ratio, and (3) the yield of the ${\beta}$-SiC powder production increased with an increase in the C/Si molar ratio.

• Biomedical Science Letters
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• v.19 no.2
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• pp.164-167
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• 2013

Osteoclasts are originated from hemopoietic progenitors of the monocyte/macrophage lineage and resorb mineralized tissues. Elevated osteoclast numbers and activity result in bone disease such as osteoporosis, Paget's disease, and tumor osteolysis. In order to identify the genes that are involved in osteoclast differentiation, microarray was performed after treated with RANKL for 12 h and 24 h in osteoclast precursors. The genes that changed by RANKL treatment were grouped by biological process or molecular function. Among them, the number of genes involved in signal transduction and nucleic acid binding was 6065 and 3066, respectively. When analyzed the number of genes changed more than 1.5 fold in the cells treated with RANKL for 12 h or 24 h compared to when RANKL was not treated, 83 and 62 genes were up-regulated; 56 and 62 genes were downregulated, respectively. To verify the microarray results, real-time RT-PCR for Cxcl1 and Slfn1genes that have not been reported yet related to osteoclast differentiation, as well as Ccl2 gene associated with osteoclast differentiation were carried out. Both experiments showed a similar result of more than 1.5 fold induction of these genes by RANKL treatment. These results suggest the possibility that Cxcl1 and Slfn1 may associate with osteoclastogenesis and provide that microarray is a useful tool to analyze the profile of genes changed during osteoclast differentiation by RANKL. Moreover, this gene profile contributes to understand the regulatory mechanisms involved in osteoclast differentiation and the pathogenesis, thus developing therapeutics of bone diseases such as osteoporosis.

• Journal of the Korean Chemical Society
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• v.61 no.4
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• pp.185-190
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• 2017

One-dimensional CdTe nanorods (NRs) are obtained by the reaction of various Cd precursors with single crystalline Te nanorod templates, which are pre-synthesized from Te precursors by a simple and reproducible solvothermal method. Throughout the process, the diffraction intensity of different crystal facets of single crystalline Te NRs varied with reaction times. Finally, by alloying Cd ions along the axial direction of Te NRs, polycrystalline cubic phase CdTe NRs with diameters of 80-150 nm and length up to $1.2-2.4{\mu}m$ are obtained. The nucleation and growth processes of Te and CdTe NRs are discussed in details, and their properties are characterized by XRD, SEM, TEM, Raman scattering, and UV-vis absorption spectra. It was found that the key elements of synthesizing CdTe NRs such as reaction temperatures and Cd sources will strongly influence the final shape of CdTe NRs.

• Development and Reproduction
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• v.20 no.3
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• pp.227-235
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• 2016

Ultrastructural studies on oocyte development and vitellogenesis in oocytes, and the functions of follicle cells during oogenesis and oocyte degeneration were investigated to clarifyb the reproductive mechanism on vitellogenesis of Scapharca subcrenata using electron microscope observations. In this study, vitellogenesis during oogenesis in the oocytes occured by way of autosynthesis and heterosynthesis. Of two processes of vitellogenesis during oogenesis, the process of endogenous autosynthesis involved the combined activity of the Golgi complex, mitochondria and rough endoplasmic reticulum. However, the process of exogenous heterosynthesis involved endocytotic incorporation of extraovarian precursors at the basal region of the oolema of the early vitellogenic oocytes before the formation of the vitelline coat. In this study, follicle cells, which attached to the previtellogenic and vitellogenic oocytes, were easily found. In particular, the follicle cells were involved in the development of previtellogenic oocytes by the supply of nutrients, and vitellogenesis in the early and late vitellogenic oocytes by endocytosis of yolk precursors. Based on observations of follicle cells attached to degenerating oocytes after spawning, follicles of this species are involved in lysosomal induction of oocyte degeneration for the resorption phagosomes (phagolysosomes) in the cytoplasm for nutrient storage, as seen in other bivalves. In this study, the functions of follicle cells can accumulate reserves of lipid granules and glycogen particles for vitellogenesis from degenerating oocytes after spawning.

• Journal of Korean Society on Water Environment
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• v.20 no.2
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• pp.145-150
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• 2004

This study investigated the effect of chlorine dose and chlorine reaction time for the formation of haloacetic acids (HAAs). According to the results, HAA formation was highly affected by chlorine dose and chlorine reaction time. HAA formation reached a plateau value at 30 mg/L of chlorine dose and 24 hr of chlorine reaction time. For the speciation of formed HAAs in the test water, the concentration of brominated-HAAs was significantly lower than that of chlorinated-HAAs because of low level of bromide ion concentration in the test water. It also investigated the removal efficiency of HAA precursors by several unit processes, such as ozone alone, UV alone, and combined ozone/UV system. Of them, ozone/UV system was proved as the best process to control the HAAs formation. The increase of the brominated-HAAs was observed during ozonation with and without UV irradiation showing the slight increase of total HAA concentrations.