• 대한화학회지
• /
• 제40권9호
• /
• pp.607-614
• /
• 1996

$ABO_3$계 perovskite 구조에서 A자리의 $Pb^{2+}$ 이온이 $Na^+La^{3+}$혼합 이온 으로 0-50mol.%치환된 $Pb_{1-x}(Na_12/La_12)_x(Mg_13/Nb_23/)O_3$ 화합물의 구조변화와 유전 성질을 X-선 회절법, 작외선과 라만 분광법, LCR meter등으로 연구하였다. $Na^+La^{3+}$혼합 이온의 치환량과 소결 온도가 증가함에 따라 perovskite 상의 양이 증가하였다. 치환량이 증가할 때 1:1 질서화에 의한 초격자선을 X-선 회절법으로 발견할수 없었지만, 라만 분광법과 이완성 매개변수의 증가로부터 A자리 양이온의 크기감소가 질서화에 영향을 미침을 알 수 있었다. Pb_{1-x}(Na_12/La_12)_x(Mg_13/Nb_23/)O_3$의 유전 성질은 perovskite 상의 양과 낟알 크기 및 밀도에 의해 영향을 받았고, 치환량이 증가할 때 상전이는 확산되었으며 상전이 온도는 감소하였다.

• JSTS:Journal of Semiconductor Technology and Science
• /
• 제9권3호
• /
• pp.166-173
• /
• 2009

The reliability of hafnium oxide gate dielectrics incorporating lanthanum (La) is investigated. nMOSFETs with metal/La-doped high-k dielectric stack show lower $V_{th}$ and $I_{gate}$, which is attributed to the dipole formation at the high-k/$SiO_2$ interface. The reliability results well correlate with the dipole model. Due to lower trapping efficiency, the La-doping of the high-k gate stacks can provide better PBTI immunity, as well as lower charge trapping compared to the control HfSiO stacks. While the devices with La show better immunity to positive bias temperature instability (PBTI) under normal operating conditions, the threshold voltage shift (${\Delta}V_{th}$) at high field PBTI is significant. The results of a transconductance shift (${\Delta}G_m$) that traps are easily generated during high field stress because the La weakens atomic bonding in the interface layer.

• 대한전자공학회:학술대회논문집
• /
• 대한전자공학회 2000년도 하계종합학술대회 논문집(2)
• /
• pp.28-31
• /
• 2000

In this paper, the effects of La addition of PLZT(x/30/70) thin films Prepared by sol-gel method are investigated for NVFRAM application. The tetragonality (c/a), the grain size, and the surface roughness of PLZT thin films decrease with an increase of La concentration. As the La concentration increases, the dielectric constants at 10 kHz increase from 450 to 600, while the loss tangent decrease from 0.075 to 0.025. Also, the leakage current density at 100kV/cm decrease from 5.83$\times$10$^{-7}$ to 1.38$\times$10$^{-7}$ 4/$\textrm{cm}^2$. In the results of hysteresis loops measured at $\pm$170kV/cm, the remanent polarization and the coercive field of PLZT thin films with La concentration from 0 to 10㏖％ decrease from 20.8 to 10.5 $\mu$C/cm and from 54.48 to 32.12kV/cm, respectively. After a fatigue measurement by applying 10$^{9}$ square pulses with $\pm$5V, the remanent polarizations of PLZT thin films with 0 and 10㏖％ La concentration decrease about 64 and 42 ％ from initial state. In the results of retention measurement after 10$^{5}$ s, PLZT thin films with 0 to 10mo1％ La concentration show that the remanent polarization is decreased about 43％ and 9％ from initial state, respectively.

• 한국의류산업학회지
• /
• 제16권5호
• /
• pp.680-688
• /
• 2014

The aim of this research is to classify intrinsic attribution of 'la diff$\acute{e}$rance images' which are core propositions of changeability of fashion style. The specific questions of this research are; what are the definition of 'changeability of fashion', 'la diff$\acute{e}$rance' and 'supplement' and what are the relationships?, how the la diff$\acute{e}$rance images which are intrinsic of changeability of fashion style exist? and what is intrinsic attribution of 'ultimate la diff$\acute{e}$rant image', 'immediate la diff$\acute{e}$rant image' and 'la diff$\acute{e}$rant image of the trace'? The researchers deployed a qualitative research method providing a systematic review of the previous studies. In conclusion, the 'supplement' phenomenon and 'la diff$\acute{e}$rant images' shown in the changeability of fashion style, covers up the gap between the structural layers through the play led by supplement logic in the subconscious place of la diff$\acute{e}$rance of dialectical frame. They produce styles that have current value and become generalized la diff$\acute{e}$rant images of trace through the play of 'la dissemination.' These images repeat their individual play to reproduce a new different 'la diff$\acute{e}$rant images' and complete the aesthetics of harmony in the state of 'reservation,' 'deferment' and 'postponement'. The images are ready to make history and they create 'ultimate la diff$\acute{e}$rant images' from the demand of different period, and tries to combine with 'supplement' within 'the gap of la diff$\acute{e}$rance.' This process endlessly repeats in the dialectical frame through the la diff$\acute{e}$rant' play led by time and space, and it continuously produces new style that is required by different time and space.

• Journal of Plant Biotechnology
• /
• 제31권3호
• /
• pp.249-253
• /
• 2004

생물반응기의 형태에 따른 인삼부정근의 생장과 ginsen-side의 생산능력에 대하여 조사한 결과, 원형의 상부와 하부에 5 cm의 bubble column을 가진 bulb type bubble bioreactor (BU)에서 건물중은 41.92 g으로 가장 많이 증가하였으며, cylindric tube bioreactor (CT)에서 건물중이 38.55g으로 가장 낮게 나타났다. 이들 두 생물반응기의 초기 kLa 값은 BU 생물반응기에서 6.98 h$^{-1}$로 가장 높게 측정되었고, 반대로 bubble column이 없는 CT 생물반응기에서 5.25 h$^{-1}$으로 가장 낮게 측정되었다. 그러나 이와 같은 초기 kLa값의 차이는 부정근내의 이차대사산물인 ginsenoside의 함량에는 영향을 주지 않는 것으로 나타났다. 또한 BU 생물반응기에서 bubble column의 길이를 기존의 5 cm에서 10 cm로 연장시켰을 때, 초기 kLa값이 6.52 h$^{-1}$에서 7.80 h$^{-1}$로 증가하면서 인삼부정근의 생장을 42.13 g에서 50.30 g으로 약 16% 증가시킨 것으로 나타났다.

• Bulletin of the Korean Chemical Society
• /
• 제33권4호
• /
• pp.1303-1309
• /
• 2012

A novel ligand N,N'-(2,6-pyridinedicarbonyl)bis[N-(carboxymethyl)] (L1) was designed and synthesized. Four co-luminescence groups of Sm-La-pyridyl carboxylic acids systems were researched, which are $K_4Sm_{(1-x)}-La_x(L_1)Cl_3{\cdot}y_1H_2O$, $K_4Sm_{(1-x)}La_x(L_2)Cl_3{\cdot}y_2H_2O$, $K_6Sm_{2(1-x)}La_{2x}(L_3)Cl_6{\cdot}y_3H_2O$, $K_4Sm_{(1-x)}La_x(L_4)Cl_3{\cdot}y_4H_2O$. The results indicated the addition of La(III) could sensitize the luminescence of Sm(III) obviously in a certain range, enhancing emission intensity of Sm-pyridyl carboxylic acids relative to the undoped ones. The optimal mole percentages of La(III) in the mixed ions for $L_1$, $L_2$, $L_3$, $L_4$ were confirmed to be 0.6, 0.5, 0.3, 0.6, respectively. The mechanism of the fluorescence enhancement effect was discussed in detail. Furthermore, the binding interaction of $K_4Sm_{0.4}La_{0.6}(L_4)Cl_3{\cdot}5H_2O$ with bovine serum albumin (BSA) have been investigated due to its potential biological activity. The binding site number n was equal to 1.0 and binding constant $K_a$ was about $2.5{\times}10^5\;L{\cdot}mol^{-1}$.

• 한국표면공학회지
• /
• 제29권6호
• /
• pp.839-846
• /
• 1996

Epitaxial (La, Sr)$CoO_3/Pb(Zr,\;Ti)O_3/(La,\;Sr)CoO_3$by pulsed laser deposition for ferroelectric field effect transistor. Epitaxial $LaCoO_3/Pb(Zr,\;Ti)O_3/(La,\;Sr)CoO_3$ heterostructures exhibited 70$\mu C/cm^2$ and 17 $\mu C/cm^2$at a positively and negatively poled states, respectively. On the other hand, epitaxial (La, Sr)$CoO_3/Pb(Zr,\;Ti)O_3/LaCoO_3$heterostructures show the remnant polarization states opposite to the $LaCoO_3/Pb(Zr,\;Ti)O_3/(La,\;Sr)CoO_3$ heterostructures. This indicates that the interface between (La, Sr)$CoO_3$ (LSCO) and $Pb(Zr, Ti)O_3(PZT)$ layers affects the asymmetric polarization remanence through electrochemical nature. The resistivity of $LaCoO_3$ (LCO) layer was found to be dependent on an ambient oxygen, primarily the ambient oxygen pressure during deposition. The resistivity of the LCO layer varied in the range of 0.1-100 $\Omega$cm. It is suggested that, with an appropriate resistivity of the LCO layer, the LCO/PZT/LSCO heterostructure can be used as the ferroelectric field effect transistor.

• 동아시아식생활학회지
• /
• 제15권4호
• /
• pp.405-412
• /
• 2005

Quality characteristics of squid-sikhae prepared by four different methods(SHM: sikhae method, SHM-LA; sikhae method added with L plantarum, MM; mixed method of sikhae method and salting method, MM-LA; MM method added with L plantarum) were investigated during fermentation at $20^{\circ}C$. The pHs of all the 6-days fermented sikhae samples were in the range of 4.01-3.76, meaning that there were no significant difference in pH according to the preparation methods. Number of total microbes(TM) were decreased, while the ratio of lactic acid bacteria against TM in SHM-LA and MM-LA was higher than those of SHM and MM. There were no differences in acid protease activity, while $NH_2-N$ content of SHM and MM were higher than those of SHM-LA and MM-LA. Amylase activity was the lowest in MM-LA. Proteins separated by SDS-PAGE belonged to 7-200 kDa, the major proteins (153<94<41 kDa) of the sikhae in all plots were disappeared at 6 days fermentation. In sensory evaluation, sour taste of MM was the highest, while it was the lowest in SHM-LA. Sweet taste, bitter taste, salty taste and hot taste were not significantly different Off-flavor was decreased in lactic acid bacteria added products. Scores of the softness and overall acceptability were the highest in SHM-LA. These results indicated that SHM-LA was the best method for the preparation of squid sikhae because of the enhancement of lactic acid fermentation and overall acceptability.

• 한국식품영양과학회지
• /
• 제41권3호
• /
• pp.310-319
• /
• 2012

본 연구에서는 기능적 특성이 우수한 우유 단백질 소재를 개발하여 식품산업에 응용하고자 우유 ${\alpha}$-La의 영양생리학적 특성에 대하여 분석하였다. 우유 ${\alpha}$-La의 기능성을 향상 시키려는 시도로써 MTGase의 첨가가 이 단백질의 이화학적 및 면역학적 특성에 미치는 영향을 조사하고, 수종의 암세포주의 생육에 대한 억제 효과를 탐색하였으며, ${\alpha}$-La의 구조적 상태에 따라 항암활성의 관련성을 검토하였다. ${\alpha}$-La에 반응한 MTGase에 의해 생성된 중합체는 인체 내 가수분해효소에 의해 분해가 용이한 것으로 확인되었다. 위암 세포주에 ${\alpha}$-La을 10 mg/mL 농도로 처리한 경우 높은 세포독성을 나타냈다. ${\alpha}$-La과 올레산의 복합체인 BAMLET은 간암 세포주에서 ${\alpha}$-La에 비해 더 강한 활성을 보였다. BAMLET은 apo 상태로 상당량의 이차구조를 지니고 있지만, 소수성 중심부는 느슨하게 형성된 MG와 같은 형태를 지니고 있을 것으로 추정되었다. NMR 분석 결과, BAMLET은 1.2 ppm과 0.8 ppm에서 지방산 보조인자인 올레산과 상호 작용하는 것으로 분석되었다.

• 공업화학
• /
• 제8권4호
• /
• pp.568-574
• /
• 1997

Ni/MH전지에서 Cu 도금이 MH(metal hydride)음극의 전극 특성에 미치는 영향을 실험적으로 조사하였다. $LaNi_5$와 Cu도금된 $LaNi_5$를 활물질로 사용하여 냉간압착법과 페이스트법의 혼용법으로 전극을 제조하였다. 그 결과 소량의 CMC(carboxymethylcellulose sodium salt)를 첨가하고 열처리를 행하지 않은 전극이 높은 방전용량을 보였다. $LaNi_5$보다는 Cu 도금된 $LaNi_5$를 활물질로 사용하여 제조한 전극의 방전용량이 증가하였으며, 이는 $LaNi_5$표면에 도금된 구리에 의해 전극의 전자 전도도가 증가되었기 때문이며 도금된 구리의 양이 증가할 수록 그 효과는 현저하였다. 또한 전극의 방전용량은 산성 무전해도금의 경우가 알칼리성 무전해도금을 행한 전극보다 우수한 용량을 나타내었다. Al이 첨가된 $LaNi_{4.5}Al_{0.5}$ 전극이 $LaNi_5$전극보다 우수한 방전용량을 보였다. 구리 도금이 $LaNi_5$의 피독특성에 미치는 영향을 CO기체의 피독실험으로 조사하였다.