• Title/Summary/Keyword: PLT

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Pyroelectric Properties of the PLT Thin Films Prepared by Sol-Gel Method (Sol-Gel법으로 제조한 PLT박막의 초전 특성)

  • 김양선;정장호;박인길;이성갑;이영희
    • Electrical & Electronic Materials
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    • v.10 no.6
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    • pp.541-547
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    • 1997
  • (Pb$_{1-x}$ La$_{x}$)Ti$_{1-x}$ $_4$O$_3$(x=0, 0.02, 0.04, 0.08) ceramic thin films were fabricated by Sol-Gel method. A stock solution of (Pb, La)TiO$_3$ with excess Pb 10 mol% was made and spin-coated on the Pt/Ti/SiO$_2$/Si substrate at 400rpm for 30 seconds. Coated specimens were dried on the hot-plate at 35$0^{\circ}C$ for 10 min and sintered at 500~75$0^{\circ}C$ for 1 hour. The dielectric constant, remanent polarization and coercive field of the PLT(6at.%) thin films sintered at $650^{\circ}C$ were 884, 13.95$\mu$C/$\textrm{cm}^2$ and 8.7kV/cm, respectively. Pyroelectric coefficient, figure of merit of pyroelectric current, voltage responsivity and detectivity of PLT(6at.%) thin films were 3.2$\times$10$^{-8}$ C/$\textrm{cm}^2$K, 1.02$\times$10$^{-8}$ C.cm/J, 2.9 $\times$10$^{-11}$ C.cm/J, 0.29$\times$10$^{-8}$ C.cm/J, respectively.ely.

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Fabrication of pyroelectric IR sensors with PLT thin plates compensating for piezoelectric effect (PLT 박편을 이용한 압전특성이 보상된 초전형 적외선 센서의 제작)

  • Kim, Young-Eil;Roh, Yong-Rae;Choi, Sie-Young
    • Journal of Sensor Science and Technology
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    • v.6 no.1
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    • pp.1-5
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    • 1997
  • Highly sensitive pyroelectric IR sensors were fabricated with La-modified $PbTiO_{3}(PLT)$ thin plates compensating for piezoelectric effect. The device was fabricated in a dual form by placing two PLT cells, each of $1{\times}2\;mm^{2}$, side by side with appropriate electrode configuration. The dual element sensor had a signal to noise ratio of about 350 that was much larger than that of single element sensors. Further the dual element sensors exhibited excellent pyroelectric properties such as a large voltage responsivity of 2400 V/W, a pyro-coefficient of $4.6{\times}10^{-8}\;C/cm^{2}K$, a voltage figure of merit of $4.2{\times}10^{-11}\;Ccm/J$, and a small thermal time constant of 8.7 msec. It was confirmed through experiments that the dual element sensor was applicable to detect the two-dimensional moving direction of human beings.

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Fabrication of MgO(100)/$Si_3N_4/SiO_2/Si_3N_4$/Si Substrate for Pyroelectric IR Sensor (초전형 적외선 센서를 위한 MgO(100)/$Si_3N_4/SiO_2/Si_3N_4$/Si 기판 제작)

  • Kim, Sung-Woo;Sung, Se-Kyoung;Ryu, Jee-Youl;Choi, Woo-Chang;Choi, Hyek-Hwan;Lee, Myoung-Kyo;Kwon, Tae-Ha
    • Journal of Sensor Science and Technology
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    • v.9 no.2
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    • pp.90-95
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    • 2000
  • The substrate for pyroelectric IR sensor which has orientation similar to MgO single crystal was fabricated by depositing the MgO thin film on $Si_3N_4/SiO_2/Si_3N_4$/Si. The MgO thin film was deposited by RF magnetron sputtering. The c-axis orientation of PLT thin film deposited on Pt/MgO(100)/$Si_3N_4/SiO_2/Si_3N_4$/Si substrate was investigated. The MgO thin film deposited at $500^{\circ}C$ at a gas pressure of 30 mTorr with RF power of 160 W exhibited a good a-axis orientation. The PLT thin films deposited on these substrates also exhibited c-axis orientation similar to the PLT thin films deposited on MgO single crystal substrate.

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Evaluation of Vacutainer Distribution Conditions (진공채혈관의 상태에 따른 평가)

  • Park, Chang-Eun
    • Korean Journal of Clinical Laboratory Science
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    • v.48 no.2
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    • pp.109-113
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    • 2016
  • Pre-analytical variables account for most laboratory errors and many factors affect the results from a patient. Type of tubes facilitated rapid separation and prevented hemolysis upon prolonged storage. However, there were some limitations associated with vacutainer conditions. To circumvent the problems, the comparability of complete blood cell count values was examined using various vacutainers. The results of the analysis showed a large coefficient variation of 0.24, 0.21 in the value of white blood cells and platelets, and significant correlation was observed between white blood cells, platelets, and the value of red blood cells (p<0.01). In each of the three tubes, compared to the value of platelets, white blood cells, the greatest coefficient variation was 0.27, 0.21. In correlation of the three companies, significant difference was observed in values of white blood cells, platelets, and platelet distribution width (p<0.01), however G and B, the value of platelets, and platelet distribution width were significantly lower (p<0.05). In conclusion, analysis of vacutainers showed that they were suitable for stability of these analytes under vacutainer conditions.

Hydrogen Post-annealing Effect of (Pb0.72,La0.28)Ti0.93O3 Films Fabricated by Pulsed Laser Deposition (펄스레이저 증착법으로 제작된(Pb0.72,La0.28)Ti0.93O3박막의 수소후열처리에 관한 전기적 특성 연구)

  • 한경보;전창훈;전희석;이상렬
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.16 no.3
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    • pp.190-194
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    • 2003
  • Dielectric thin films of (P $b_{0.72}$,L $a_{0.28}$) $Ti_{0.93}$ $O_3$ (PLT(28)) have been deposited on Pt(111)/Ti/ $SiO_2$/Si(100) substrates in-situ by pulsed laser deposition using different annealing and deposition Processes. We have investigated the effect of hydrogen annealing on the ferroelectric properties of PLT thin films and found that the annealing process causes the diffusion of hydrogen into the ferroelectric film resulting in the destruction of polarization. We have tried to form the film by a two-step deposition process In order to improve electrical property. Two-step process to grow PLT films was adopted and verified to be useful to enlarge the grain size of the film and to reduce the leakage current characteristics. Structural properties and electrical properties including dielectric constant, ferroelectric characteristics, and leakage current of PLT thin films were shown to be strongly influenced by grain size. The film deposited by using two-step Process including pre-annealing treatment has a strongly(111) orientation. However, the films deposited by using single -step process with hydrogen annealing process show the smallest grain size. The film deposited by using two-step process including pre-annealing treatment shows the leakage current density of below 10$^{-7}$ A/c $m^2$ for the field of smaller than 100 kV/cm. However, the films deposited by using single-step process with hydrogen annealing process and pre-annealing process show worse leakage current density than the film deposited by using two-step process including pre-annealing treatment.tment.

Positive Regulation of Pyoluteorin Biosynthesis in Pseudomonas sp. M18 by Quorum-Sensing Regulator VqsR

  • Huang, Xianqing;Zhang, Xuehong;Xu, Yuquan
    • Journal of Microbiology and Biotechnology
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    • v.18 no.5
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    • pp.828-836
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    • 2008
  • The biocontrol rhizobacterium Pseudomonas sp. M18 can produce two kinds of antibiotics, namely pyoluteorin (Plt) and phenazine-1-carboxylic acid (PCA), and is antagonistic against a number of soilborne phytopathogens. In this study, a luxR-type quorum-sensing regulatory gene, vqsR, was identified and characterized immediately downstream of the Plt gene cluster in strain MI8. A vqsR-inactivated mutant led to a significant decrease in the production of Plt and its biosynthetic gene expression. However, this was restored when introducing the vqsR gene by cloning into the plasmid pME6032 in trans. The vqsR mutation did not exert any obvious influence on the production of PCA and its biosynthetic gene expression and the production of N-acylhomoserine lactones (C4 and C8-HSLs) and their biosynthetic gene rhlI expression. Accordingly, these results introduce VqsR as a regulator of Plt production in Pseudomonas spp., and suggest that the regulatory mechanism of vqsR in strain M18 is distinct from that in P. aeruginosa. In addition, it was demonstrated that vqsR mutation did not have any obvious impact on the expression of Plt-specific ABC transporters and other secondary metabolic global regulators, including GacA, RpoS, and RsmA.

A Study on the Loading Capacity Standard of Bi-directional Pile Load Test (BD PLT) (양방향말뚝재하시험의 재하용량 기준에 관한 연구)

  • Choi, Yongkyu
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.28 no.6C
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    • pp.379-388
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    • 2008
  • In the bi-directional pile load test (BD PLT) for pile load tests of Mega pile foundations, loading capacity standard is not specified exactly. Therefore there are so many confusions in performing the BD PLT and variations up to maximum 2 times in loading capacity are come out. In this study, standards of bi-directional pile load test (BD PLT) were considered. Based on cases of the bi-directional pile load test performed in domestic areas, maximum equivalent test load, test load increasing ratio, loading capacity increasing ratio and sufficiency ratio of design load were analyzed. It could be known that the loading capacity standard of bi-directional pile load test must be defined as 1-directional loading capacity and also must be established as more than 2 times of design load.

A Hystesis Loop Modeling of Ferroelectric Thin Film Using Numerical Integration Method (수치적분을 이용한 강유전체의 이력곡선 모델링)

  • 강성준;정양희;유일현
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2003.05a
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    • pp.696-699
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    • 2003
  • In this study, we suggested the model to precisely evaluate the ferroelectric hysteresis loop, using the modified Sawyer-Tower circuit and the ferroelectric capacitor with a MDFM(Metal-Dielectric-ferroelectric-Metal) structure. The mathematical expression of dipole polarization is applied to the numerical integration algorithm, and the fatigue property can be considered including the dielectric layer between ferroelectrics and bottom electrode. The validity of our model is proved comparing the estimated value of our model and the measured results of PLT(10) thin film.

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Characteristics of quasi-MFISFET device with various ferroelecric thin films (강유전체 박막의 특성에 따른 Quasi-MFISFET 소자의 특성)

  • Lee, Guk Pyo;Yun, Yeong Seop;Gang, Seong Jun
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.38 no.3
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    • pp.12-12
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    • 2001
  • PLZT(10/30/70), PLT(10) 및 PZT(30/70) 와 같은 강유전체 박막의 이력곡선을 field-dependent polarization 모델을 이용하여 시뮬레이션하고, 측정한 실험적 결과와 비교, 분석하였다. PZT(30/70) 박막의 경우, 5V 이상의 인가전압에서 분극의 포화현상이 둔감하게 나타나고 시뮬레이션 값과의 차이도 심해 강유전체 분극이 순수한 dipole 외에도 다양한 전하의 영향을 받아 형성된다는 사실을 알 수 있다. 또, quasi-MFISFET 소자의 드레인 전류는 field-dependent polarization 모델의 강유전체 이력곡선에서 얻은 파라미터를 square-law FET 모델에 적용시켜 효과적으로 추출하였고, 모델링 결과는 실험값과 유사하였다. 그리고, quasi-MFISFET 소자의 gate 에 -10V의 ′write′ 전압을 인가한 상태에서 PZT(30/70) 박막을 사용한 경우, PLZT(10/30/70), PLT(10) 박막 보다 빨리 채널이 형성되었는데, 그 원인은 강유전체 박막에 따른 retention 특성에서 PZT(30/70) 박막의 분극 감소가 PLZT(10/30/70), PLT(10) 박막의 분극 감소 보다 약 3∼4 배 이상 크다는 점에서 찾을 수 있다.

Evaluation of Platelet Indices in Lung Cancer Patients

  • Oncel, Mufide;Kiyici, Aysel;Oncel, Murat;Sunam, Guven Sadi;Sahin, Emel;Adam, Bahattin
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.17
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    • pp.7599-7602
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    • 2015
  • Background: In this study, we aimed to determine platelet indices such as platelet count (PLT), mean platelet volume (MPV), platelet distribution width (PDW), Plateletcrit (PCT) platelet count (PLT) in lung cancer cases, and evaluate any relationships between these parameters and stage or histologic types. Materials and Methods: This retrospective study covered 44 lung cancer patients and 47 healthy subjects. Platelet indices including PLT, PCT, MPV, PDW were estimated and compared with normal subjects. The results were evaluated statistically. Results: The PDW value was significantly higher in the cancer group compared to the control group; however, the values for PCT and MPV were lower. Conclusions: We suggest potential use of platelet indices in diagnosis of lung cancer.