• Animal Systematics, Evolution and Diversity
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• v.12 no.1
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• pp.1-15
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• 1996

Twenty six species of 8 genera of the Korean Cochylini belonging to Tortricidae, excluding a genus Phalonidia, are recognized during the course of this study. Among them 7 species, Aethes citreoflavus Kuznetsov, Cochylidia heydeniana (Herrich- Sch$\ddot{a}$ffer), C. moguntiana (R$\ddot{o}$sier), Eupoecilia angustana (H$\ddot{u}$bner), E. kobeana Razowski, Pseudargyrotoza calvicaput (Walsingham), and Stenodes cuspidatus Ge, are reported for the first time from Korea. A key to the genera is given. Male and female genitalic structures of 7 unrecorded species are briefly redescribed and illustrated.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.2
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• pp.308-315
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• 2011

Ammonium- and potassium-loaded zeolite (NK-Z) and other four kinds of environmental friendly fertilizers/agents were applied to characterize their effectiveness on garlic (Allium sativum L.) growth and soil amelioration. Selenium dioxide ($SeO_2$) and germanium dioxide ($GeO_2$) liquid treatments significantly increased selenium (Se) and germanium (Ge) contents in garlic stems, garlic cloves and clove peels. In soil treated with ZBFC, Se contents in garlic stems, cloves, and clove peels was 13.89-, 12.79-, and 10.96-fold higher, respectively, than in the controls. The inorganic contents of plants grown in soil treated with functional strengthened fertilizers were also higher than in plants grown in control soil. Soil treated with arbuscular mycorrhizal fungi (AMF) agents exhibited significantly greater spore density and root colonization rate than in untreated soil. The density of chitinolytic microorganisms in soil treated with colloidal chitin was also significantly higher than in untreated soil. The cation exchange capacities (CEC) in ZAFC-, ZBFC-, and ZBF-treated soils was 16.05%, 8.95%, and 8.80% higher than in control soil 28 weeks after sowing.

• Journal of Radiation Protection and Research
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• v.34 no.2
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• pp.83-86
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• 2009

The single crystal scintillator of bismuth germinate ($Bi_4Ge_3O_{12}$:BGO) was successfully grown by the conventional Czochraski technique. The characteristics of the grown BGO were evaluated and presented on the excitation, emission responses and energy spectra of the $\gamma$-rays from $^{241}Am$, $^{133}Ba$, $^{57}Co$, $^{22}Na$, $^{137}Cs$ and $^{54}Mn$ radio-isotopes. The energy resolution of grown BGO, $\Delta$E/E, was estimated to be 12.1% at 662 keV of $\gamma$-ray for $^{137}Cs$ nuclide. Compared to the commercial BGO crystal, we confirmed that the grown BGO has a good performance and is comparable to reference one.

• Journal of the Korean Ceramic Society
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• v.38 no.12
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• pp.1167-1173
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• 2001

The tetragonal tungsten bronze type of Sr$_{x}Ba_{1-x}Nb_{2}O_{6}$(SBN) (0.3$\le$x$\ge$0.7) ceramics was synthesized by the solid state reaction method, and the dielectric properties of SBN ceramics as a function of Sr/Ba ratio were examined. With increasing Sr/Ba ratio in SBN ceramics, the Curie temperature decreased and the maximum dielectric constant at the Curie temperature increased. The relaxor behavior of the SBN ceramics as a function of Sr/Ba ratio was quantitatively evaluated. More relaxor behavior of dielectric characteristics was observed as the ratio of Sr/Ba increased. The experimental results are explained with a viewpoint of crystallography of tungsten bronze structured SBN ceramics.

• Journal of the Korean Ceramic Society
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• v.34 no.4
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• pp.436-442
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• 1997

The bimodal distribution of CuCl nano-crystals precipitated in alumino-borosilicate glass matrix (30SiO2-45B2O3-7.5Al2O3-7.5Na2O-7.5CaO-2.5GeO2(mole %)) was investigated by TEM and the temperature dependent optical spectroscopy. Two types of CuCl particles with different size were observed by TEM and it was confirmed by the splitting of Z3 absorption peak at low temperature and the occurrence of deflection point in the optical spectra with temperature.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.436-437
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• 2006

The $Ag/TiO_{2-x}N_x$ nanoparticles were synthesized by photochemical deposition in a $TiO_{2-X}N_X$ suspension system. The prepared products were characterized by means of XRD, Uv-vis and photoluminescence spectra (PL). Its photocatalytic activity was investigated by the decomposition of methylene blue (MB) solution under illumination of visible and ultraviolet light, respectively. Compared to $TiO_{2-x}N_x$, the photocatalytic activity of the as-prepared $Ag/TiO_{2-x}N_x$ is obviously enhanced due to the decreasing recombination of a photoexcitated electron-hole pairs. The Mechanism in which photocatalytic activity is enhanced has been discussed in detail.

• Journal of the Korean Ceramic Society
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• v.40 no.1
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• pp.98-103
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• 2003

The effect of glass addition on the low-temperature sintering and microwave dielectric properties in $BaO-Nd_2O_3-TiO_2$ dielectric ceramics were studied. When 10~30 wt% of alkali lithium borosilicate glass was added, the sintering temperature decreases from $1300^{\circ}C$;to;1000^{\circ}C$ and the relative density more than 95% was obtained. When the added amount of glass increased above 10 wt%, the density as well as dielectric properties changed, which was attributed to the second phase formation. When the sample was sintered at 100$0^{\circ}C$ with l0wt% of glass, the dielectric properties of $Qxf_o{ge}2800,;{varepsilon}_r{ge}65;and;{ au_f=+55 ppm/^{\circ}C$ were obtained.

• Journal of the Korean Ceramic Society
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• v.23 no.3
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• pp.87-93
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• 1986

Yttria-bismuth-stabilized zirconia was investigated with respect to the amount of $Bi_2O_3$ addition in the ran-ge of 0.5~5mol% to the base composition of $(ZrO_2)_{0.92}(Y_2O_3)_{0.08}.Bismuth was introduced into the ma-terial with $Bi_2O_3-SiO_2$ glasses in order to reduce the evaporation of components. The sinterbility evaporation of components phase formation and microstructure were evaluated depending on the amount of $Bi_2O_3-SiO_2$ glass addition. Two probe A. C conductivity measurement was subjected to all the specimens and the result was discussed on the possible substitution of $Bi^{3+}$ for $Zr^{4+}$ and interistial $Si^{4+}$ in the fluorite structure of zirconia crystal there-upon the possible change in the capability of oxygen transference within the material. It was found that the addition of $Bi_2O_3$ could improve the sinterbility of material very much while not so much.oxygen sensing material suitable for relative low temperature firing.

• JSTS:Journal of Semiconductor Technology and Science
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• v.16 no.2
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• pp.172-178
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• 2016

In this paper, we propose a sub-10 nm Ge/GaAs heterojunction-based tunneling field-effect transistor (TFET) with vertical band-to-band tunneling (BBT) operation for ultra-low-power (LP) applications. We design a stack structure that is based on the Ge/GaAs heterojunction to realize the vertical BBT operation. The use of vertical BBT operations in devices results in excellent subthreshold characteristics with a reduction in the drain-induced barrier thinning (DIBT) phenomenon. The proposed device with a channel length ($L_{ch}$) of 5 nm exhibits outstanding LP performance with a subthreshold swing (S) of 29.1 mV/dec and an off-state current ($I_{off}$) of $1.12{\times}10^{-11}A/{\mu}m$. In addition, the use of the highk spacer dielectric $HfO_2$ improves the on-state current ($I_{on}$) with an intrinsic delay time (${\tau}$) because of a higher fringing field. We demonstrate a sub-10 nm LP switching device that realizes a good S and lower $I_{off}$ at a lower supply voltage ($V_{DD}$) of 0.2 V.

• Journal of the Korean Vacuum Society
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• v.6 no.1
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• pp.36-43
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• 1997

FECAPS(ferroelectric capacitors) have been fabricated by RF magnetron sputtering deposition of 3000$\AA$ PZT thin films on the Pt/Ti/$SiO_2$/Si substrates and post-annealing with the temperature of $550^{\circ}C$~$650^{\circ}C$ for 10 sec~50 sec in a RTA system. The electrical characteristics of the fabricated capacitors showed the highest dielectric constant and remanent polarization[${\varepsilon_r(1kHz)$=690, $2P_r$(-5V~5V sweep)=22$\mu$C/$ \textrm{cm}^2$] in the samples annealed at $650^{\circ}C$ for 30 sec, while the lowest tangent loss and leakage current [$tan\delta(\ge10kHz)\le0.02, \; J_i(5V)=3\mu\textrm{A}/\textrm{cm}^2$]in the samples annealed at $600^{\circ}C$ for 30 sec.