• 대한금속재료학회지
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• 제50권10호
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• pp.711-720
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• 2012

In this study, the effect of aging treatment on the microstructure and tensile properties of AZ61-xPd (x = 0, 1 and 2 wt%) alloys were investigated. The microstructure of as-cast AZ61-xPd alloys mainly consisted of ${\alpha}-Mg$, $Mg_{17}Al_{12}$ and $Al_4Pd$ phases. After solution treatment, most of the $Mg_{17}Al_{12}$ phases were dissolved into the Mg matrix. Thereafter, $Mg_{17}Al_{12}$ phases were finely formed and distributed near thermally stable $Al_4Pd$ phases and inside the grains through aging treatment at $220^{\circ}C$ during 88 hours. With the aging at $220^{\circ}C$, the peak aged AZ61-xPd alloys showed higher hardness than as-cast and solution treated AZ61-xPd alloys. In particular, the AZ61-1Pd alloy was optimized due to refined $Mg_{17}Al_{12}$ and $Al_4Pd$ phases. Further, the peak aging time was reduced with increasing Pd addition (>1 wt%). Tensile strength was increased by Pd addition at $25^{\circ}C$, $150^{\circ}C$, both as-cast and peak aged AZ61-xPd alloys. After aging treatment, room and high temperature tensile strength were increased more than the as-cast specimens. The AZ61-1Pd alloy especially showed the largest strength increase range. Elongation was decreased with addition Pd at $25^{\circ}C$ and $150^{\circ}C$.

• 한국동물번식학회:학술대회논문집
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• 한국동물번식학회 2003년도 학술발표대회 발표논문초록집
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• pp.73-73
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• 2003

본 연구는 돼지 체세포의 clonal cell lines을 효율적으로 확립할 수 있는 배양방법을 제시하기 위하여 실시하였다. 50일령의 돼지태아로부터 섬유아세포를 회수하여 2회 계대배양 후 단일 세포를 96-well plate와 4-well dish에서 배양하여 배양액내의 FBS농도(10, 30, 50%), 첨가제(catalase, $\beta$-mercaptoethanol; BME), 세포의 크기(<16, 16~20, 20<) 및 형태(smooth, rough)에 따른 cell line 확립 효율을 검토하였다. FBS 농도에 따른 clonal line 확립 효율과 PD를 검토한 결과, 효율에 있어서 30% FBS 처리구(5.1%)가 10%(0.3%) 및 50%처리구(2.1%)보다 비교적 높게 나타났으나 유의적 차이는 없었으며, PD의 경우는 10, 30, 50%처리구에서 각각 36.7, 29.4, 26.3 시간으로 FBS 농도가 증가할수록 PD 시간이 유의적으로 짧아졌다(p<0.05). 배양액 첨가제에 있어서 BME 가시 무처리구나 catalase 첨가시보다 유의적으로 높은 효율을 보였으며(11.4%, 3.2%, 3.2%; p<0.05), PD 시간은 짧게 나타났다(23.6, 25.5, 28.1; p<0.05). 그러나 catalase는 cell line 확립 효율에 영향을 미치지 않는 것으로 나타났다. 세포의 크기에 따른 cell line 확립효율은 5.2~8.2%로 크기에 따른 차이는 보이지 않았으며, PD 또한 23.7~27.9 시간으로 세포 크기에 따른 차이는 없었다. 세포의 형태에 따른 세포의 부착율은 smooth(55.8%)구가 rough(73.0%)구보다 유의적으로 낮게 나타났으나(p<0.05), clonal line 확립 효율(7.7%n vs. 6.6%) 및 PD(23.5h vs. 24.0h)에서는 차이가 없었다. 본 연구의 결과, 세포의 형태에 따른 cell line 확립 효율은 큰 차이가 없었으나, 세포 배양액내에 30% FBS와 BME의 첨가로 clonal cell line 확립 효율을 향상시킬 수 있음을 확인할 수 있었다. 또한 cell line 확립 효율이 높아질수록 PD 시간이 짧아지는 경향을 볼 수 있었다.

• 한국표면공학회지
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• 제50권2호
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• pp.98-107
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• 2017

Pd-based membranes have been widely used in hydrogen purification and separation due to their high hydrogen diffusivity and infinite selectivity. However, it has been difficult to fabricate thin and dense Pd-based membranes on a porous stainless steel(PSS) support. In case of a conventional PSS support having the large size of surface pores, it was required to use complex surface treatment and thick Pd coating more than $6{\mu}m$ on the PSS was required in order to form pore free surface. In this study, we could fabricate thin and dense Pd membrane with only $3{\mu}m$ Pd layer on a new PSS support manufactured by metal injection molding(MIM). The PSS support had low surface roughness and mean pore size of $5{\mu}m$. Pd membrane were prepared by advanced Pd sputter deposition on the modified PSS support using fine polishing and YSZ vacuum filling surface treatment. At temperature $400^{\circ}C$ and transmembrane pressure difference of 1 bar, hydrogen flux and selectivity of $H_2/N_2$ were $11.22ml\;cm^{-2}min^{-1}$ and infinity, respectively. Comparing with $6{\mu}m$ Pd membrane, $3{\mu}m$ Pd membrane showed 2.5 times higher hydrogen flux which could be due to the decreased Pd layer thickness from $6{\mu}m$ to $3{\mu}m$ and an increased porosity. It was also found that pressure exponent was changed from 0.5 on $6{\mu}m$ Pd membrane to 0.8 on $3{\mu}m$ Pd membrane.

• KIEE International Transactions on Electrophysics and Applications
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• 제11C권2호
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• pp.6-11
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• 2001

Abstract- In this paper, a new Partial Discharge (PD) detection using Pockels cell was proposed and considerable apparent chaotic characteristics were discussed. For this purpose, PD was generated from needle-plane electrode in air and detecte by optical measuring system using Pockels cell, based on Mach-Zehner interferometer, consisting of He-Ne laser, single mode optical fiber, 50/50 beam splitter and photo detector. In addition, the presence of chaos of the PD signals has been investigated by examining their means of qualitative and quantitative information. For the former, return map and 3-dimensional strange attractor have been drawn in order to investigate the presence of chaotic characteristics relevant to PD signals, detected through CT and Peckels sensor respectively, in the normalized time series. The presence of strange attractor indicates the existence of fractal structures in it's phase space. For the latter, several dimension values of strange attractor were verified sequentially. Throughout this paper, it is likely that the chaotic characteristics regarding the PD signals under air are verified.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 C
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• pp.1850-1852
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• 2000

In this paper, new Partial Discharge (PD) detection technique using Pockels cell was proposed and considerable apparent chaotic characteristics were discussed. For this purpose, PD was generated from needle-plane electrode in air and detected by optical measuring system using Pockels cell, based on Mach-Zehnder interferometer, consisting of He-Ne laser, single mode optical fiber, 50/50 beam splitter and photo detector. A qualitative analysis was carried out by drawing Return map for the normalized time series of the detected PD signals. The results are as follows:(a) Fixed points, between 0.7 and 1.0, are appeared clearly in the right upper area of the return map as the increase in the number of obtained data.(b) Considerable periodicity have been remarked even though exact period and length can not be determined.(c) The self-similarity can be also observed inasmuch as the late paths do not follow the previous ones. Accordingly, exact quantitative analysis such as embedding dimension, fractal dimension, and Lyapunov exponents should be carried out for deducing the quantitative properties regarding PD phenomena.

• 폴리머
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• 제26권3호
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• pp.410-414
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• 2002

중심 금속을 안정화시킬 수 있는 ferrocene-based diimine 리간드를 가지고 낮은 산소 친화성을 가진 후전이금속인 Pd 촉매를 합성하여, 극성 단량체인 메틸메타크릴레이트 (MMA)의 중합에 사용하였다. 중합계 내의 impurity scavenger로 triisobutylaluminium (TIBA)를 사용하였을 때에, 중합온도와 [TIBA]/[Pd] 몰비가 생성 중합체(PMMA)의 수율 및 유리전이온도 ($T_g$)에 미치는 영향을 조사하였다. PMMA의 수율은 40~$50^{\circ}C$의 중합온도 및 2000~3000의 [TIBA]/[Pd] 몰비에서 가장 높았다. PMMA의 $T_g$는 중합온도에는 크게 영향을 받지 않으나, [TIBA]/[Pd] 몰비에 의존한다는 것을 관찰할 수 있었다. PMMA의 $T_g$의 변화를 PMMA의 미세구조와 연관시켜 조사한 결과, PMMA의 $T_g$ 이소탁틱도와 직선적 관계를 가짐을 알았다.

• The Korean Journal of Physiology and Pharmacology
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• 제1권2호
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• pp.143-149
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• 1997

We studied the effects of ginseng protopanaxadiol (PD) and protopanaxatriol (PT) saponins on the analgesia using several pain tests such as writhing, formalin, and tail-flick test. Using mouse, pretreatment of PD or PT saponins (i.p.) induced inhibition of abdominal constrictions caused by 0.9% acetic acid administration(i.p.). The $AD_{50}$ was around 27 (17-43) mg/kg for PD and 13.5 (3-61) mg/kg for PT saponins in writhing test. Both PD and PT saponins also showed the inhibition of bitings and lickings of hindpaw after administration of 1% formalin. In particular, both PD and PT saponins showed analgesic effects on second phase of pain. The $AD_{50}$ was 44.5 (26-76) mg/kg for PD and 105 (55-200) mg/kg for PT saponins in second phase of formalin test. For first phase pain inhibition by PD or PT saponins, they were required higher concentrations. However, PD saponins showed weak analgesic effects in tail-flick test with high concentration. In conclusion, we found that both PD and PT saponins have the analgesic effects in writhing test and second phase of pain in formalin test. These results suggest that both PD and PT saponins inhibit neurogenic or tonic pain rather than acute pain.

• 한국진공학회지
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• 제12권4호
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• pp.218-227
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• 2003

AlGaAs/GaAs HBT 에미터 오믹 접촉을 위해 n형 InGaAs에 대한 Pd/Si/Ti/Pt 및 Pd/Si/Pd/Ti/Au 오믹 접촉 특성을 조사하였다. Pd/Si/Ti/Pt 오믹 접촉의 경우, 증착 상태에서는 접촉 비저항을 측정할 수 없을 정도의 비오믹 특성을 보였으며, $375^{\circ}C$에서 10초 동안 열처리한 경우 $5\times10^{-3}\Omega\textrm{cm}^2$의 높은 접촉 비저항을 나타내었다. 그러나 열처리 조건을 $425^{\circ}C$, 10초로 변화시킬 경우 $2\times10^{-6}\Omega\textrm{cm}^2$의 낮은 접촉 비저항을 나타내었다. Pd/Si/Pd/Ti/Au 오믹 접촉의 경우, $450^{\circ}C$까지의 열처리 동안에 전반적으로 우수한 오믹 특성을 나타내어 $400^{\circ}C$, 20초의 급속 열처리 조건에서 최저 $3.9\times10^{-7}\Omega\textrm{cm}^2$의 접촉 비저항을 나타내었다. 두 오믹 접촉 모두 오믹 재료와 InGaAs의 평활한 계면을 유지하면서 우수한 오믹 특성을 나타내어, 화합물 반도체 소자의 오믹 접촉으로 충분히 응용 가능하였다. Pd/Si/Ti/Pt 및 Pd/Si/Pd/Ti/Au를 AlGaAs/GaAs HBT의 에미터 오믹 접촉으로 사용하여 제작된 HBT 소자의 고주파 특성을 측정한 결과, 차단 주파수가 각각 63.9 ㎓ 및 74.4 ㎓로, 또한 최대공진 주파수가 각각 50.1 ㎓ 및 52.5 ㎓로 우수한 작동특성을 보였다.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2003년도 추계학술발표강연 및 논문개요집
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• pp.172-172
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• 2003

It has been known that Pd-MILC shows much faster and lower temperature crystallization than Ni-MILC but it can not be put into practice due to the quality issue of thus fabricated poly crystals. In this study, addition of Pd into Ni-MILC has been attempted in order to take advantages of the Pd-MILC without sacrificing of the Ni-MILC TFTs. It turns out that when 5% of Pd has been added to Ni for MILC, MILC growth rate increases two - three times faster than pure Ni-MILC. The MILC growth rate shows monotonic increase with increase the amount of Pd in Ni up to 50%. Even when small amount of Pd was added to Ni like 5%, crystallization phenomenon already follows the way of Pd-MILC. The Poly-W thus fabricated shows lower leakage current than pure Ni-MILC TFT without losing any amount of on-current This fact is very important in low temperature poly-TFTs because MILC-TFTs, especially suffer from the relatively high leakage current

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제55권4호
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• pp.166-171
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• 2006

In this paper, we have studied for analysis of the partial discharge(PD) signal in underground transmission line. The PD signal has estimated as detected signal accumulation of a PRPDA method by using Labview, and analyzed with fuzzy algorithm. In our algorithm, we developed system configuration that detected accumulating PD signal using by Labview and programmed fuzzy algorithm can be analyzed the PD signal using with Matlab. With practical PD logic implementation of theoretical detected system and hardware implementation, the device for Hipotronics Company's 50kV setup has generated and then has applied with $15k{\sim}17kV$ with 1:1 time probe. It's also used the LDPE 0.27mmt (scratch error 0.05mmt) to sample for making PD. In conclusion, Our new class of PD detected algorithm has also compared with previous PRPDA or Fuzzy algorithm. which has diagnose more conveniently by adding numerical values.