• 한국세라믹학회지
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• 제30권11호
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• pp.925-932
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• 1993

The perovskite phase in PZN-PMN-PT (Pb(Zn, Mg)1/3Nb2/3O3-PbTiO3) pseudoternary ceramics was stabilized by the addition of excess constituent divalent oxides (PbO, MgO and ZnO). The excess addition of 5mol% MgO or 7.5mol% PbO fully stabilized the perovskite phase. The enhanced diffuse phase transition (DPT) and the decrease in the electrical resistivity observed in the presence of excess ZnO or MgO were interpreted in terms of the additional formation of negatively charged, short-range ordered 1:1 domains with a concomitant generation of charge carriers, holes.

• Journal of Power Electronics
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• 제15권6호
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• pp.1446-1455
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• 2015

This paper illustrates resonant tank design considerations and the implementation of a LLC resonant converter with a wide battery voltage range based on the fundamental harmonic approximation (FHA) analysis. Unlike the conventional design at zero load, the parameter K (the ratio of the transformer magnetizing inductor L_m to the resonant inductor L_r) of the LLC converter in this paper is designed with two charging points, (V_{o_min}, I_{o_max1}) and (V_{o_max}, I_{o_max2}), according to the battery charging strategy. A 2.9kW prototype with an output voltage range of 36V to 72V dc is built to verify the design. It achieves a peak efficiency of 96%.

• 한국자기학회지
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• 제17권1호
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• pp.6-9
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• 2007

양자얽힘 상태를 만들어내는 것은 매우 중요하다. 근거리에 있는 두 계를 양자얽힘 상태로 만드는 것은 그리 어렵지 않으나 직접 상호작용이 불가능 할 정도로 멀리 떨어져서 고정되어 있는 계들을 양자적으로 얽히게 하는 것은 어려운 문제 중의 하나다. 본 논문에서는 먼 거리에 떨어져있는 스핀-1/2입자들 사이에 양자얽힘 상태를 직접적인 상호작용이 아니라 제 삼의 스핀-l/2를 이용하여 생성할 수 있다는 것을 보였다. 상호작용으로는 $F\"{o}rster$ 상호작용과 스핀-스핀 교환 상호작용을 사용하였다.

• Current Optics and Photonics
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• 제2권6호
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• pp.606-611
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• 2018

Measurement of the nonlinear optical coefficients is not an easy task since it requires complicated experimental setup and analysis. We suggest an easy way to estimate the relative nonlinear optical tensor components by direct measurement of the output powers of the second harmonic generation and spontaneous parametric down conversion experiments. The experiments were done in quasi-phase-matched type-0 as well as type-1 interactions at similar pump wavelengths in a 5% MgO-doped periodically poled $LiNbO_3$ crystal to obtain the ratio of the nonlinear optical tensor components $d_{33}/d_{31}$ in each experiment. The obtained ratios were then compared with the previously ascertained values [J. Opt. Soc. Am. B, 14, 2268-2294 (1997)].

• 한국응용곤충학회지
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• 제19권4호
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• pp.243-248
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• 1980

가, 숯검은밤나방은 1회 발생으로 9월하순이 최성기였고 짐거세미나방 및 거세미나방은 년 $2\~3$회 발생으로 1화 6월중순, 2화기 8월중순, 3화기 9월하순에 최성기를 보였다. 나, 거세미나방류의 각태별 기간은 숯검은나방은 난기간 6.3일 유충기간 327.1, 용기간 25.1, 성충기간 6.5로 유충기간이 길었고 검거세미나방은 난기간 4.2일, 유충기간 29.6일, 용기간 17.5일, 성충기간 5.2일 이었고 거세미나방은 난기간 5.6일, 유충기간 38.2일, 용기간 27.3일, 성충기간 5.7일이었다. 다, 거세미나방류는 배추의 잎이 축 늘어진 잎 뒷면에 산란하였다. 라. 거세미나방 유충의 토중 잠토 시기는 3령이후였다. 마, 거세미나방류의 천적으로는 고치별 1종과 맵시벌 2종이 발견되었다. 바, 거세미나방류의 방제약제로는 모캡 및 보라톤이 효과적이었으나 보라톤은 작물체에 직접 닿으면 약해가 유발되므로 세심한 주의를 요한다.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 2003년도 Annual Meeting of KSAP : International Symposium on Pharmaceutical and Biomedical Sciences on Obesity
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• pp.83-83
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• 2003

In our previous study, glucose deprivation was reported to induce the potentiated death and ATP loss in immunostimulated astroglia. And this vulnerability to glucose deprivation was due to overproduction of nitric oxide (NO) and hydrogen peroxide (H$_2$O$_2$). In the present study, the role of extracellular signal-regulated kinase 1/2 (ERK1/2) in the glucose deprivation-induced death of immunostimulated astroglia was examined. We showed that immunostimulation with LPS+IFN-ν activated the ERKl/2 signal pathway and produced a large amount of NO and H$_2$O$_2$. Generation of NO and H$_2$O$_2$ in immunostimulated astroglia was mediated via ERK1/2 signal pathways, since addition of the ERK kinase (MEKl) inhibitor PD98059 reduced NO and H$_2$O$_2$production. ERK1/2 activation-mediated NO and H$_2$O$_2$ production is due to an activation of iNOS and NADPH oxidase, respectively. Finally, we found that glucose deprivation caused ATP depletion and the augmented death in immunostimulated astroglia, which was also prevented by PD98059 treatment. These results demonstrate that the ERK1/2 signal pathways play an important role in glucose deprivation induced the death in immunostimulated astroglia by regulating the generation of NO and H$_2$O$_2$.

• 한국세라믹학회지
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• 제48권2호
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• pp.168-172
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• 2011

Alumina powder was added in a general porcelain (Backja) with clay, feldspar and quartz contents to promote the mullite ($3Al_2O_3{\cdot}2SiO_2$) generation in the porcelain. Low melting materials ($B_2O_3(450^{\circ}C)$, $MnO_3(940^{\circ}C)$, CuO($1080^{\circ}C$)) were doped at ~3 wt% to modify the sinterability of porcelain with a high alumina contents and promote the mullite generation. Green body was made by slip casting method with blended slurry and then, they were fired at $1280^{\circ}C$ for 1hr by a $2^{\circ}C/min$. Densifications of samples with high alumina contents (20~30 wt%) were impeded. As the doping contents of low melting materilas increased, the sinterability of samples was improved. The shrinkage rate and bulk density of samples were improved by doping with low melting materials. Mullite phase increased with increasing the low melting contents in the phase analyses. This means lots of alumina and quartz were transformed into mullite phase by low melting contents doping. In the results, high bending strength of samples with high alumina contents was accomplished by improving the densification and mullite generation in the porcelain.

• 동의생리병리학회지
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• 제23권2호
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• pp.464-472
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• 2009

The aim of this study was to investigate the effects of Cheonghyul-san on the generation of peroxynitrite ($ONOO^-$), nitric oxide (NO) and superoxide anion radical ( ${\cdot}\;O_2^-$), and on the expression of NF-${\kappa}$B-dependent proinflammatory proteins in ob/ob mice. Mice were grouped and treated for 5 weeks as follows. Both the normal lean (C57BL/6J black mice) and control obese (ob/ob mice) groups have received the standard chow. The experimental groups were fed with a diet of chow supplemented with 7.5, 15 and 30 mg Cheonghyul-san per 1 kg of body weight for 14 days. For this study, the fluorescent probes, namely 2',7'-dichlorodihydrofluorescein diacetate (DCFDA), 4,5-diaminofluorescein-2 (DAF-2) and dihydrorhodamine 123 (DHR 123) were used. Western blot was performed using anti-IKK-${\alpha}$, anti-phospho I${\kappa}$B-${\alpha}$, anti-NF-${\kappa}$B (p50, p65), anti-COX-2, anti-iNOS, anti-VCAM-1 antibodies, respectively. Cheonghyul-san prevented $H_2O_2$-induced cell death. Cheonghyul-san inhibited the generation of $ONOO^-$, NO and ${\cdot}\;O_2^-$ in the $H_2O_2$-treated LLC-$PK_1$ cells. The generation of $ONOO^-$, NO and ${\cdot}\;O_2^-$ were inhibited in the Cheonghyul-san-administered ob/ob mice groups. The GSH/GSSG ratio was decreased in the ob/ob mice, whereas the ratio was improved in the Cheonghyul-san-administered groups. Cheonghyul-san inhibited the protein expression levels of phospho-I${\kappa}$B-${\alpha}$, IKK-${\alpha}$, NF-${\kappa}$B (p50, p65), COX-2, iNOS and VCAM-1 genes. These results suggest that Cheonghyul-san is an effective scavenger of $ONOO^-$, ${\cdot}\;O_2^-$ and NO, and has an inhibitory effect on the expression of NF-${\kappa}$B-dependent inflammatory genes in ob/ob mice. Therefore, Cheonghyul-san might be used as a potential therapeutic drug against the diabetes- and obesity-related proinflammatory diseases.

• 한국광학회:학술대회논문집
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• 한국광학회 1989년도 제4회 파동 및 레이저 학술발표회 4th Conference on Waves and lasers 논문집 - 한국광학회
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• pp.250-254
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• 1989

Second-harmonic generation at a silver-electrolyte (0.1 M KCL + H2O) interface was enhanced by surface roughness. The intensity of the second-harmonic radiation was shown to be sensitive enough to detect molecular monolayers adsorbed on a silver surface.

• Bulletin of the Korean Chemical Society
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• 제32권12호
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• pp.4366-4370
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• 2011

A simple, green and cost-effective protocol was used for the aromatization of 1,3,5-trisubstituted-2-pyrazolines to the corresponding pyrazoles by in situ generation of iodine ($I^+$) from $H_2O_2$/AcOH or SSA or oxalic acid /KI or NaI system under thermal condition with moderate to good yields.