• 전기화학회지
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• 제7권4호
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• pp.167-172
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• 2004

3,4-dihydroxybenzaldehyde(3,4-DHB) was oxidatively el electropolymerized on glassy carbon (GC) electrodes to prepare CC/p-3,4-DHB type electrodes, which were subsequently modified with 3,4-dihydroxybenzoic acid(3,4-DHBA) using 0.05M HCI as a catalyst. The esterification reactions were performed between -OH sites on the polymeric film surface of the p-3,4-DHB and the -COOH sites within the 3,4-DHBA molecules in solution. These reactions had a rate constant value of $1.1\times10^{-1}\;s^{-1}$ for the esterification step as obtained from the first-order rate constant in the solution. The electrochemical responses of the GC/p-3,4-DHB-3,4-DHBA electrodes exert an influence upon the buffer solution, its pH and applied potential ranges. The redox process of the electrode was more easily controlled by charge transfer kinetics than that of the CC/p-3,4-DHB. The modified electrodes had redox active sites that were 10 times more active than those present before modification. The electrical admittance of the modified electrodes was also three times higher than that of the unmodified electrodes. After being annealed in ethanol for 20 hrs the electrodes brought about a 3.3 times greater change of water molecules in the redox reaction. The modified electrodes are stable in the potential range of 0.4 to 0.55V.

• 대한방사선기술학회지:방사선기술과학
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• 제31권3호
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• pp.293-298
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• 2008

본 연구는 방사선 조사에 의해 생쥐의 혈청성분이 어떠한 변화를 일으키는가를 구명하는데 있고, 이를 위해 10MeV급 Linac 방사선치료장치를 사용하여 3Gy 방사선을 1회 전신 조사한 생쥐의 혈청(serum)을 채취하여 14가지 생화학적 분석을 실시한 후 paired t-test를 실시하였다. 그 결과 다음의 3가지 혈청성분에서 유의한 변화가 있다는 사실을 확인하였다. 첫째, glucose 측정에서 정상대조군(normal control group)의 $185.43{\pm}14.93$보다 방사선조사군(irradiation group)이 $220.00{\pm}17.58$로 높게 나타나 평균값에 매우 유의한 차이를 보였다(p<0.001). 둘째, BUN(blood urea nitrogen) 측정에서 정상대조군의 $19.61{\pm}1.65$보다 방사선조사군이 $15.70{\pm}1.48$로 낮게 나타나 평균값에 유의한 차이를 보였다(p<0.01). 셋째, albumin 측정에서 정상대조군의 $3.19{\pm}0.34$보다 방사선조사군이 $2.89{\pm}0.25$로 낮게 나타나 평균값에 유의한 차이를 보였다(p<0.05). 결론적으로, 3Gy 방사선이 조사된 생쥐의 혈청은 glucose, BUN(blood urea nitrogen), albumin 등 3가지 성분에서 유의할만한 변화를 일으켰다.

• 한국환경보건학회지
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• 제23권2호
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• pp.83-88
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• 1997

To evaluate the effect of bromobenzene pretreatment on the bromobenzene metabolism, the animal group was induced the stage of slight liver damage with 7 times bromobenzene injection every two days (400 mg/kg body wt. i.p.). In the present experimental animal model, the single dose of bromobenzene(400 mg/kg body wt. i.p.) was injected to the bromobenzene-pretreated rats and the hepatic aniline hydroxylase(AH) activity, glutathione(GSH) content and glutathione S-transferase (GST) activity were determined at the intervals of 2, 4, 8, 24 hours throughout 24 hr. The activities of hepatic AH and GST were generally higher in bromobenzene-pretreated rats than those in normal group throughout the whole course of experiment. Furthermore, the decreasing rate of hepatic GSH content was also higher in bromobenzene pretreated rats than in normal rats. Moreover, the value of V$_{max}$ in hepatic GST was higher in bromobenzene pretreated rats than that in the normal rats. In conclusion, these results indicate that the pretreatment of bromobenzene may rather enhance the bromobenzene metabolism.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 춘계학술대회 논문집 전자세라믹스 센서 및 박막재료 반도체재료 일렉트렛트 및 응용기술
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• pp.80-83
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• 2000

The post-annealing treatments on rf magnetron sputtered PZT($Pb_{1.05}(Zr_{0.52},\;Ti_{0.48})O_3$) thin films($4000{\AA}$) have been investigated for a structure of PZT/Pt/Ti/Coming glass(1737). Crystallization properties of PZT films were strongly dependent on RTA(Rapid Thermal Annealing) annealing temperature and time. We were able to obtain a perovskite structure of PZT at $650^{\circ}C$ and 10min. P-E curves of Pd/PZT/Pt capacitor demonstrate typical hysteresis loops. The measured values of $P_r$, $E_c$ were $8.1[{\mu}C/cm^2]$, 95[kV/cm] respectively. Polarization value decrease about 25% after $10^9$ cycles.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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• pp.844-846
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• 2008

A new p-type conjugated copolymer, poly(9,10-diethynylanthracene-alt-9,9-didodecylfluorene (PDADF) was synthesized through a Sonogashira coupling reaction. A solution-processed thin film transistor device showed a carrier mobility value of $6.0\;{\times}\;10^{-4}\;cm^2/Vs$ with a threshold voltage of -17 V and a capacitance ($C_i$) of $10\;nF/cm^2$.

• Journal of Magnetics
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• 제2권4호
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• pp.116-122
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• 1997

To determine whether there is an ionic substitution of Ni, Co, Mn, and Al for Fe in synthetic goethites these materials have been studied by M$\ddot{o}$ssbauer spectroscopy at various temperatures ranging from 77 to 400 K. It is found that the presence of substituting elements in magnetically ordered structure of crystals may change the shape of M$\ddot{o}$ssbauer spectra of these caterials. The approximate distribution function of the effective magnetic field in the Fe nucleus p(Hn) is obtained from the M$\ddot{o}$ssbauer spectra. It is noted that the mean value of p(Hn) and its integral width can be taken as a measure of substitution in goethites.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 C
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• pp.1477-1479
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• 2000

The annealing treatments on rf magnetron sputtered PZT($Pb_{1.05}(Zr_{0.52},Ti_{0.48})O_3$) thin films(4000${\AA}$) have been investigated for a structure of PZT/Pt/Ti/ITO coated glass. Crystallization properties of PZT films were strongly dependent on RTA(Rapid Thermal Annealing) annealing temperature and time. We were able to obtain a perovskite structure of PZT at 650$^{\circ}C$ and 10min. P-E curves of Pd/PZT/Pt capacitor demonstrate typical hysteresis loops. The measured values of $P_r$, $E_c$ were 15.8[${\mu}C/cm^2$], 95[kV/cm] respectively. Polarization value decrease about 10% after $10^9$ cycles.

• 한국전기전자재료학회논문지
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• 제29권3호
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• pp.164-167
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• 2016

In this study, in order to develop relaxor ferroelectric ceramics for refrigeration device application with large electrocaloric effect, PLZT(8/65/35) composition was fabricated using conventional solid-state method. The Curi temperature of this composition PLZT ceramics was $230^{\circ}C$, and the P-E hysteresis loops of the PLZT ceramics as a fuction of temperature became slim by degrees with higher temperatures. The maximum value of ${\Delta}T$ of $0.243^{\circ}C$ in ambient temperature of $215^{\circ}C$ with 30 kV/cm was appeared. It is considered that PLZT ceramics possess the possibility of refrigeration device application.

• Journal of Magnetics
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• 제15권4호
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• pp.185-189
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• 2010

Spin polarized tunneling through a hybrid tunnel barrier of a Spin filter (SF) based on a EuO ferro-magnetic semiconductor and an organic semiconductor (OSC) (rubrene in this case) was investigated. For quasi-magnetic tunnel junction (MTJ) structures, such as Co/rubrene/EuO/Al, we observed a strong spin filtering effect of the EuO layer exhibiting I-V curves with high spin polarization (P) of up to 99% measured at 4 K. However, a magnetoresistance (MR) value of 9% was obtained at 4.2 K. The low MR compared to the high P could be attributed to spin scattering caused by structural defects at the interface between the EuO and rubrene, due to nonstoichiometry in the EuO.

• Food Science and Biotechnology
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• 제16권1호
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• pp.159-162
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• 2007

Optimization of the fermentation medium for phenylethyl alcohol (PEA) production by Pichia anomala SKM-T was performed. The carbon source (glucose), nitrogen source (L-phenylalanine), and initial pH value were independent variables of the optimized medium. The central composite rotatable design was used for the experimental design and the analysis of the results. The optimum medium composition for the maximal production (621.27 mg/L) of PEA was found to be an initial pH of 5.03, and concentrations of L-phenylalanine at 6.53 and glucose at 6.11 g/L (w/v). This experimental finding is in close agreement with the model prediction (702.79 mg/L; desirability 0.884) with an 11.6% difference.