• Journal of the Korean Chemical Society
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• v.31 no.2
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• pp.178-183
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• 1987

The kinetics of the reaction of $[Mo_3O_4(H_2O)_9]^{4+}$ with $VO_2^+$have been studied at $25^{\circ}C$ by spectrophotometric method. With$VO_2^+$ in excess, the $[Mo_3O_4(H_2O)_9]^{4+}$ reaction can be expressed as $Mo^{IV}_3+6V^V{\rightleftarrows}3Mo^{IV}+6V^IV}$. Observed rate constants for the reaction are dependent on [$H^+$] and [$VO_2^+$]. Mechanism for the redox of $[Mo_3O_4(H_2O)_9]^{4+}$and $VO_2^+$ is proposed and discussed.

• Communications of the Korean Mathematical Society
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• v.30 no.3
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• pp.313-325
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• 2015

An H-magic labeling in a H-decomposable graph G is a bijection $f:V(G){\cup}E(G){\rightarrow}\{1,2,{\cdots},p+q\}$ such that for every copy H in the decomposition, $\sum{_{{\upsilon}{\in}V(H)}}\;f(v)+\sum{_{e{\in}E(H)}}\;f(e)$ is constant. f is said to be H-V -super magic if f(V(G))={1,2,...,p}. In this paper, we prove that complete bipartite graphs $K_{n,n}$ are H-V -super magic decomposable where $$H{\sim_=}K_{1,n}$$ with $n{\geq}1$.

• Journal of the Korean Ceramic Society
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• v.35 no.12
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• pp.1329-1336
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• 1998

A twt -step carbothermal reduction scheme has been employed for the synthesis of SiC whiskers in an Ar or a H2 atmosphere via vapor-solid two-stage and vapor-liquid-solid growth mechanism respectively. It has been shown that the whisker growth proceed through the following reaction mechanism in an Ar at-mosphere : SiO2(S)+C(s)-SiO(v)+CO(v) SiO(v)3CO(v)=SiC(s)whisker+2CO2(v) 2C(s)+2CO2(v)=4CO(v) the third reaction appears to be the rate-controlling reaction since the overall reaction rates are dominated by the carbon which is participated in this reaction. The whisker growth proceeded through the following reaction mechaism in a H2 atmosphere : SiO2(s)+C(s)=SiO(v)+CO(v) 2C(s)+4H2(v)=2CH4(v) SiO(v)+2CH4(v)=SiC(s)whisker+CO(v)+4H2(v) The first reaction appears to be the rate-controlling reaction since the overall reaction rates are enhanced byincreasing the SiO vapor generation rate.

• Proceedings of the KIPE Conference
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• 2016.07a
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• pp.279-280
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• 2016

전기자동차를 위한 양방향 탑재형 충전기의 장내구성을 달성하기 위해 전해캐패시터를 사용하지 않는 전력변환장치가 요구된다. 본 논문에서는 V2G-V2H 기능을 갖는 무 전해캐패시터 양방향 탑재형 충전기의 제어알고리즘을 제안한다. 제안하는 양방향 충전기는 정현파 충전방식이 적용되었고 인버터만 제어하여 V2G-G2V-V2H 모드전환이 끊김없는 장점을 갖는다 제안하는 알고리즘을 검증하기 위한 3.3kW급 시작품의 시험결과로 타당성을 검증하였다.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1238_1239
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• 2009

본 논문에서는 ELA poly-Si TFT보다 뛰어난 균일도를 갖고, a-Si:H TFT보다 전기적 안정도가 우수한 PMOS SPC-Si TFT의 특성을 연구하였다. SPC-Si의 계면 특성을 향상 시키기 위해 $SiO_2$ 게이트 절연막을 증착하기 전에 Solid Phase Crystalline 실리콘(SPC-Si) 채널 영역에 다양한 H2 플라즈마 처리를 해주었다. PECVD를 이용하여 100W에서 H2 플라즈마 처리를 5분 해주었을 때 SPC-Si TFT의 전기적 특성이 향상되는 것을 볼 수 있는데, $V_{TH}$가 약 -3.91V, field effect mobility가 $22.68cm^2$/Vs, 그리고 Subthreshold swing이 0.64 정도를 보였다. 또한 소자에 Hot carrier stress($V_{GS}$=14.91V, $V_{DS}$=-15V, for 2,000sec)를 주었을 때도 전기적 특성이 변하지 않았으며, 일정한 bias stress($V_{GS}$=-15V, $V_{DS}$=-10V, for 2,000sec)를 가하였을 때도 $V_{TH}$가 증가하지 않았다. 이러한 결과를 통해 SPC-Si가 poly-Si TFT보다 더욱 안정함을 알 수 있었다.

• Journal of the Korean Applied Science and Technology
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• v.16 no.3
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• pp.205-210
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• 1999

The Mo(V) $di-{\mu}-oxo$ type $[Mo_2O_4(H_2O)_2L]Cl_2$ complexes(L: 4,4'-Diphenyl-2,2'-dipyridyl, 4,4'-Dimethyl-2,2'-dipyridyl, 4,7-Diphenyl-1,10-phenanthroline) have been prepared by the reaction of $[Mo_2O_4(H_2O)_6]^{2+}$ with a series of chelate ligands. These complexes are completed by two terminal oxygens arranged trans to one another and each ligand forms a chelate types. In $Mo_2O_4(H_2O)_2L$ two $H_2O$ coordinated at trans site of terminal oxgens. The prepared complexes have been characterized by elemental analysis, infrared spectra, electronic spectra, $^1H$ nuclear magnetic resonance spectra, and thermal analysis(TG-DTA). In the potential range -0.00V to -1.00V at scan rate of $50mVs^{-1}$, a cathodic peak at -0.83V ${\sim}$ -0.88V (vs SCE) and an anodic peak at -0.54V ${\sim}$ -0.88V (vs SCE) have been observed in aquous solution. The ratio of the cathodic to anodic current(Ipc/Ipa) is almost 2, we infer that redox is irreversible as dimer forms broken.

• Journal of Life Science
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• v.13 no.4
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• pp.498-504
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• 2003

This Study was carried out to investigate the optimal mycelial growth of Pholiota nameko. The optimal medium for the mycelial growth was ME medium. The optimal temperature and pH were $25^{\circ}C$$\pm$1 and 5.5, respectively. The modified optimal medium compositions were glucose 3% (w/v), malt extract 0.25% (w/v), yeast extract 0.25% (w/v), $KH_2PO_4$ 0.046% (w/v), $K_2HPO_4$ 0.1% (w/v), $MgSO_4$ㆍ$7H_2O$ 0.05% (w/v). From the result of experiments on the optimal temperature, pH and nutritional requirements, the mycelial growth of modified optimal medium was higher than that of ME medium.

• Bulletin of the Korean Chemical Society
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• v.26 no.8
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• pp.1185-1189
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• 2005

Two new copper vanadium borophosphate compounds, $(NH_4)(C_2H_{10}N_2)_{5.5}[Cu(C_2H_8N_2)_2]_3[V_2P_2BO_{12}]_6{\cdot}17H_2O,\;Cu-VBPO1\;and\;(NH_4)(C_2H_{10}N_2)_{3.5}[Cu(C_2H_8N_2)_2]_5[V_2P_2BO_{12}]_6{\cdot}18H_2O$, Cu-VBPO2 have been hydrothermally synthesized and characterized by single crystal X-ray diffraction, thermogravimetric analysis, IR spectroscopy, and elemental analysis. The structure of Cu-VBPO1 contains a layer anion, {$[Cu(C_2H_8N_2)_2]_3[V_2P_2BO_{12}]_6$}$^{12-}$, whereas Cu-VBPO2 has an open framework anion, {$[Cu(C_2H_8N_2)_2]_5[V_2P_2BO_{12}]_6$}$^{8-}$. Crystal Data: $(NH_4)(C_2H_{10}N_2)_{5.5}[Cu(C_2H_8N_2)_2]_3[V_2P_2BO_{12}]_6{\cdot}17H_2O$, monoclinic, space group I2/m (no. 12), $\alpha$ = 15.809(1) $\AA$, b = 31.107(2) $\AA$, c = 12.9343(8) $\AA$, $\beta$ = 104.325(1)$^{\circ}$, Z = 2; $(NH_4)(C_2H_{10}N_2)_{3.5}[Cu(C_2H_8N_2)_2]_5[V_2P_2BO_{12}]_6{\cdot}18H_2O$, tetragonal, space group $P4_2$/mnm (no.136), $\alpha$ = 26.832(1) $\AA$, c = 18.021(1) $\AA$, Z = 4.

• Microbiology and Biotechnology Letters
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• v.14 no.2
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• pp.193-198
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• 1986

Improvement of productivity in ethanol fermentation was attempted using a hollow fiber bioreactor (HFR) where Saccharomyces cerevisiac var. ellipsoideus cells were recycled to achieve a high yeast concentration. Industrial wort was used as the fermentation media without supplying any additional nutrients. The performances in hollow fiber recycle reactor (HFR) were compared with those of batch and continuous cultures. In a continuous culture with 11$^{\circ}$P and 15$^{\circ}$P wort media final ethanol concentrations were 4.71% and 5.82% (v/v) and yields 86.2% and 78.6% respectively when the dilution rate (D) was 0.1 h$^{-1}$, in contrast, the ethanol concentration and productivity in HFR were 7.64%(v/v) and 6.1g/l/h at D=0.1h$^{-1}$ with 15$^{\circ}$P media. When the dilution rate was increased to 0.2 h$^{-1}$, the concentration and the Productivity were 7.62% (v/v) and 12.2g/l/h. At D=0.3h$^{-1}$ the sugar was completely consumed and the productivity was 18.1g/l/h. This correponds to 4 times that in continuous system and 16.3 times that in the batch system performed in comparable conditions.

• Bulletin of the Korean Chemical Society
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• v.26 no.1
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• pp.146-150
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• 2005

Two new barium vanadium borophosphate compounds, $(NH_4)_2(C_2H_{10}N_2)_6[Ba(H_2O)_5]_2[V_2P_2BO_{12}]_6{\cdot}8H_2O$, Ba- VBPO1 and $(NH_4)_8(C_3H_{12}N_2)_4[Ba(H_2O)_7][V_2P_2BO_{12}]_6{\cdot}17H_2O$, Ba-VBPO2 have been synthesized by interdiffusion methods in the presence of diprotonated ethylenediamine and 1,3-diaminopropane. Compound Ba-VBPO1 has an infinite chain anion (${[BaH_2O)_5]_2[V_2P_2BO_{12}]_6}$$^{14-}$, whereas Ba-VBPO2 has a discrete cluster anion {[$Ba(H_2O)_7][V_2P_2BO_{12}]_6$}$^{16-}$. Crystal Data: $(NH_4)_2(C_2H_{10}N_2)_6[Ba(H_2O)_5]_2[V_2P_2BO_{12}]_6{\cdot}8H_2O$, triclinic, space group P$\overline{1}$ (no. 2), a = 13.7252(7) $\AA$, b = 15.7548(8) $\AA$, c = 15.8609(8) $\AA$, α = 63.278(1)$^{\circ}$, $\beta$ = 75.707(1)$^{\circ}$, $\gamma$ = 65.881(1)$^{\circ}$, Z = 1; $(NH_4)_8(C_3H_{12}N_2)_4[Ba(H_2O)_7][V_2P_2BO_{12}]_6{\cdot}17H_2O$, monoclinic, space group C2/c (no. 15), a = 31.347(2) $\AA$, b = 17.1221(9) $\AA$, c = 22.3058(1) $\AA$, $\beta$ = 99.303(1)$^{\circ}$, Z = 4.