• Journal of the Korean Crystal Growth and Crystal Technology
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• v.25 no.6
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• pp.272-279
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• 2015

$Y_2O_3:Eu^{3+}$ is an excellent red-emitting phosphor, which has been widely used for display devices due to highly luminescent property and chemical stability. In this study, $Y_2O_3:Eu^{3+}$ red phosphors were prepared using the solid state reaction and RF thermal plasma synthesis. The particle size of $Y_2O_3:Eu^{3+}$ phosphors obtained by the solid state reaction varied from 10 to $20{\mu}m$, and 30~100 nanometer sized $Y_2O_3:Eu^{3+}$ particles were obtained from a liquid form of raw material through RF thermal plasma synthesis without an additional heat treatment. Photoluminescence measurements of the obtained $Y_2O_3:Eu^{3+}$ particles showed a red emission peak at 611 nm ($^5D_0{\rightarrow}^7F_2$). PL intensity of red nano phosphors prepared by RF thermal plasma synthesis was comparable to that of red phosphors prepared by the solid state reaction, indicating that nano-sized $Y_2O_3:Eu^{3+}$ red phosphors could be successfully synthesized using one-step process of RF thermal plasma.

• Restorative Dentistry and Endodontics
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• v.22 no.2
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• pp.560-574
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• 1997

The present study was undertaken to investigate the crystal growth onto human enamel mineral and synthetic hydroxyapatite(HA) seeds in media resembling the enamel fluid composition. Effects of fluoride at high concentrations on the precipitation were also examined in a bench-top crystal growth model adopting a miniaturized reaction column. The Ca, P and F concentrations and pH values of the inlet and outlet solutions were determined. The recovered solid samples were weighed to assess the amount of minerals precipitated during the experimental period, and finally viewed under a scanning electron microscope. Remarkable findings were that 1) both biological and synthetic seeds with the same total surface areas yielded similar amounts of crystal growth, 2) the amount of crystal growth was accelerated in a manner depending on fluoride concentrations in the media, 3) SEM observations disclosed that without the addition of fluoride, precipitation of thin, plate-like OCP crystals became prominent, but by increasing the fluoride concentration(beyond 1ppm F), rod-like crystals having a pointed edge were most frequently observed, without any evidence for precipitation of the plate-like crystals. Furthermore, the dimension of rod-like crystals was increased in proportion to fluoride concentrations, 4) there was no difference in the morphological feature of precipitated mineral phase upon seeding between human enamel seed and synthetic HA seed. The overall results support the view that the seeded crystal growth model is of value to gain insight into the mechanism of enamel crystal growth under fluoride regimens.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.21 no.1
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• pp.15-20
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• 2011

[ $^7Li$ ]Magic Angle Spinning (MAS) NMR spectroscopy has been used to study the lithium local environments in $Li_4P_2O_7$ and$LiFePO_4$ materials. The purpose of this study was to know the structure of the solid electrolyte interphase (SEI) in lithium ion cells composed of $LiFePO_4$ as cathode material. $Li_4P_2O_7$ and $LiFePO_4$ were prepared by a solid-state reaction. The $^7Li$ MAS NMR experiments were carried out at variable temperatures in order to observe the local structure changes at the temperatures in $Li_4P_2O_7$ system. The $^7Li$ MAS NMR spectra of in $Li_4P_2O_7$ indicate that the lithium local environments in $Li_4P_2O_7$ were not changed in the temperature range between $27^{\circ}C$ and $97^{\circ}C$ Through this work, we confirmed that the small amount of $Li_4P_2O_7$ less than 5.0 wt% in $LiFePO_4$ could be clearly measured by the $^7Li$ MAS NMR spectroscopy at high spinning rate over than 11 kHz.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.13 no.1
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• pp.15-18
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• 2003

High purity single crystalline calcium fluoride ($CaF_2$) has excellent optical transmission characteristics down to deep UV and is therefore selected as the main optical material for the next generation of lithography apparatus operating at wavelength of 157 nm. The growth of large sized $CaF_2$ single crystals with the required properties for this optical application can be achieved only by optimizing the crystal growth process by the aid of numerical simulation. This needs especially a precise calculation of the heat transport and temperature distribution in the solid and liquid $CaF_2$ under crystal growth conditions. As $CaF_2$ is considered to be semitransparent, the internal radiative heat transfer in $CaF_2$ plays an decisive role in the simulation of the heat transport. On the other hand it is very difficult to obtain quantitative experimental data for evaluating numerical models as $CaF_2$ is extremely corrosive at high temperatures. In this work we present a newly developed experimental technique to perform temperature measurements in $CaF_2$-crystal as well as in the melt under conditions of crystal growth process. These experimental results are compared to calculated temperature data, which were obtained by using different numerical models concerning the internal heat transfer in semitransparent $CaF_2$. It will be shown, that an advanced model, which was developed by the authors, gives a much better agreement with experimental data as a standard model, which was taken from the literature.

• The Journal of the Korea Contents Association
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• v.16 no.6
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• pp.706-716
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• 2016

This study aims at finding impact of cultural and sports characteristics on urban growth. For the empirical analysis, this study uses unique urban resources associated with four categories (Social, Traffic, Cultural and Sports, and Spatial characteristics) among 228 cities and towns using a semi-log multiple regression analysis. The result shows that various local resources have significant impacts on urban growth in terms of population, industry, and fiscal self-reliance ratio. Impressively, cultural and sports resources are relatively beneficial for the urban growth. For the population and industrial growth, expanding public sports facilities and professional sports facilities can be more efficient. For solid local finance, typically focusing on professional sports facilities that have far-reaching ripple effects are useful. The conclusion for this study shows that urban growth policy should prioritize the cultural and sports resources because it can be more effective way to enhance not only for urban growth but also for quality of citizens' life.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.429.1-429.1
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• 2002

In the patients with hematologic and solid tumors. clinical application of peripheral blood stem cells (PBSCs) increases to reconstitute hematopoiesis after high-dose chemotherapy. To mobilize PBSCs. the hematopietic growth factors have been widely used as single treatment or after chemotherapy. The important issue in the collection of PBSCs is to predict their potential capability to reconstitute hematopoiesis. which depends on optimal time of leukapheresis and the quantity of collected PBSCs. (omitted)

• Archives of Pharmacal Research
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• v.14 no.1
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• pp.68-72
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• 1991

The polysaccharide fraction from Taraxii Herba showed potent immunopotentiating activities with antitumor activities. The fraction having small amount of protein inhibited the growth of solid tumor and increased peritoneal exudate cells and immunoorgan weights in normal mice, and also increased hypersensitivities in tumor bearing mice.

• Journal of Yeungnam Medical Science
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• v.32 no.1
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• pp.1-7
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• 2015

Over several decades, a hierarchical cancer stem cell (CSC) model has been established in development of solid cancers, including hepatocellular carcinoma(HCC). In terms of this concept, HCCs originate from liver CSCs. Clinically HCCs show a wide range of manifestations from slow growth to very aggressive metastasis. One of the reasons may be that liver CSCs originate from different cells. This review describes the basic concept of CSCs and the cellular origin of liver CSCs.

• Proceedings of the Korean Fiber Society Conference
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• 1998.04a
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• pp.63-66
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• 1998

The steady growth in the use of plastic materials in packaging applications has caused an increasing concern about the environment and the problem of solid waste disposal. Therefore, the recycling of plastics is the very important problem, which must be solved technically and environmentally [1]. It is technically feasible to recycle, recover and reuse all of the plastics discarded, but economics limit the degree of recycling at this time.(omitted)

• Proceedings of the Korean Society of Applied Pharmacology
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• 1998.11a
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• pp.167-168
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• 1998

Swainsonine is a toxic indolizidine alkaloid found in the plant, Swainsona species (Dorling, 1978; Colgate, 1979). It is a potent inhibitor of the glycoprotein processing pathway in the Golgi apparatus. Specifically, it inhibits mannosicase II resulting in abherrant high mannose glycans. Recent studies showed that swainsonine prevents metastasis of tumor cells and it inhibits solid growth tumor, at least partially (Goss et al., 1994; Baptista et al, 1994).