• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 C
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• pp.1627-1628
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• 2006

In this paper, mesoporous only platinum electrode and micro pore platinum electrode with mesoporous Pt are fabricated and characterized on a silicon substrate to check their usability as enzymeless sensing electrodes for developing non-disposable glucose sensors integrated with silicon CMOS read out circuitry. Since most of electrochemical glucose sensors are disposable due to the use of the enzymes that are living creatures, these are limited to use in the in-vivo and continuous monitoring system applications. The proposed mesoporous Pt electrode with approximately 2.5nm in pore diameter and 150nm in height was fabricated by using a nonionic surfactant $C_{16}EO_8$ and an electroplating technique. The micro pore Pt electrode with mesoporous Pt means the mesoporous Pt electrode fabricated on top of micro pore arrayed Pt electrode with approximately $10{\mu}m$ in pore diameter and $80{\mu}m$ in height. The measured current responses at 10mM glucose solution of plane Pt, micro pore Pt, micro pore with mesoporus Pt, and mesoporous Pt electrodes are approximately $9.9nA/mm^2$, $92.4nA/mm^2$, $3320nA/mm^2$ and $44620nA/mm^2$, respectively. These data indicate that the mesoporous Pt electrode is much more sensitive than the other Pt electrodes. Thus, it is promising for non-disposable glucose sensor and electrochemical sensor applications.

• Bulletin of the Korean Chemical Society
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• 제27권8호
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• pp.1121-1126
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• 2006

Methanol oxidation effect on carbon supported Pt was investigated as a function of Pt content in a sample which is closely correlated with Pt particle sizes. After prolonged methanol oxidation the Pt particle size did not change within the experimental error ranges. The $^{13}C$ chemical shift and linewidth of CO adsorbed on Pt show non-linear behavior simply due to the Pt particle size difference. The Pt size variation difference between this work and the previous reports of the particle growths is explained by the experimental temperature difference.

• 한국세라믹학회지
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• 제36권4호
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• pp.403-409
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• 1999

RF 마그네트론 스퍼터링방법으로 Pt/Ti/NON/Si 기판 위에 $Ba_{0.66}$$Sr_{0.38}$$TiO_{3}$(BST) 박막을 증착한 다음 유전 및 초전특성을 살펴보았다. BST 박막을 증착할 때 기판온도를 300~-$600^{\circ}C$로 변화시킨 결과 기판온도가 증가할수록 박막의 결정성과 입도가 증가하여 유전율과 초전계수가 증가하였다. 한편 하부전극인 Pt의 증착조건이 BST 박막의 몰성에 미치는 영향도 살펴보았다. Pt의 증착온도와 Pt의 미세구조와 결정성뿐만 아니라 상부에 형성된 BST 박막의 배향성에도 큰 영향을 미쳤으며, 그 결과 BST의 초전특성에도 큰 영향을 미쳤다. BST 박막과 Pt 하부전극의 증착조건을 적정화함으로써 본 연구에엇는 상온에서 초전계수가 240 $nCcm^{-2}K^{-1}$인 BST 박막을 얻었다.

• 한국수소및신에너지학회논문집
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• 제17권4호
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• pp.440-447
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• 2006

Solid polymer electrolyte(SPE) membrane with electrodes embedded on both faces offer unique possibilities for the electrochemical cells like water electrolyzer with fuel cell. The Nafion 117 membrane was used as the SPE, and $Pt(NH_3)_4Cl_2$ and $NaBH_4$ as the electrocatalysts and reducing agent, respectively. The 'impregnation-reduction(I-R) method' has been investigated as a tool for the preparation of electrocatalysts for water electrolyzer by varying the concentration of reducing agent and reduction time at fixed concentration of platinum salt, 5 mmol/L. Pt-SPE electrocatalysts prepared by non-equilibrium I-R method showed the lowest cell voltage of 2.17 V at reduction time, 90 min and with concentration of reducing agent 0.8 mol/L and the cell voltage with those by equilibrium I-R method was 2.42 V at reduction time, 60 min and with concentration of reducing agent 0.8 mol/L. The cell voltage were obtained at a current density $1\;A/cm^2$ and $80^{\circ}C$. In water electrolysis, hydrogen production efficiency by Pt-SPE electrocatalyst is 68.2% in case of non-equilibrium I-R method and 61.2% at equilibrium I-R method.

• 비파괴검사학회지
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• 제27권4호
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• pp.313-320
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• 2007

일반적으로 비파괴 검사용 초음파 탐촉자는 PZT를 이용한 압전소자가 많이 이용되어 왔다. 최근 압전특성이 PZT보다 크게 뛰어난 PMN-PT 압전 단결정 재료가 개발되어 초음파를 이용한 비파괴 평가 분야에 폭넓게 활용될 것으로 기대되고 있다. 본 연구는 PMN-PT를 이용하여 발전설비 고감쇠 재료의 비파괴 평가에 적합한 초음파 탐촉자를 개발하기 위하여 수행되었다. KLM 모델을 이용하여 초음파 탐촉자의 특성을 시뮬레이션 하였으며 이를 기반으로 하여 중심주파수 1 및 2.25 MHz PMN-PT 종파용 초음파 탐촉자를 제작하여 상용 초음파 탐촉자와 그 성능을 비교하였다.

• 대한수학회논문집
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• 제11권1호
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• pp.131-137
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• 1996

In this paper, we give a necessary and sufficient condition for the weak convergence of trajectories of non-lipschitzian asymptotically nonexpansive mappings.

• 한국광물학회지
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• 제1권1호
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• pp.15-19
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• 1988

In the process of re-checking the phase relations of the Pt-Sb system the previously reported Pt4+Sb phase did not occur. Instead, Pt34Sb7 phase with an average chemical composition (wt%) Pt 89.3, Sb 11.4, total 100.7, has been newly found to exist, and the formula Pt34Sb7 has been tentatively assigned to it, It is pale brownish grey to yellowish grey under refloecting microscope and non-bireflectant, VHN100=225 (206-243). X-ray powder patterns are (d(I/Io)): 2.318(100), 2.293(100), 2.110(30), 1.440(50), 1.390(15), 1.283(5), 1.203(70) and 1.192(40)$\AA$. They are indexable on the basis of tertragonal cell with $\alpha$=3.948(3), c=16.85(1)$\AA$. A question whether the tetragonal Pt34Sb7 is the new phase or a polymorph of the cubic Pt4+Sb phase remains unclear and awaits better X-ray diffraction, electron microprobe analysis and DTA for the Pt4+Sb phase. The Pt3Sb phase reported to be of tetragonal symmetry has been confirmed to exist. It is greyish yellow in air and in oil, very weakly bireflectant, and weakly anisotropic. VHN25=216 (183-240). Its X-ray powder data have been successively indexed on a tetragonal cell with $\alpha$=3.9455(7), c=16.959(5)$\AA$.

• 전기학회논문지P
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• 제52권1호
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• pp.14-19
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• 2003

The effect of the Pt electrode and the $Pt-IrO_2$ hybrid electrode on the performance of ferroelectric device was investigated. The modified Pt thin films with non-columnar structure significantly reduced the oxidation of TiN diffusion barrier layer, which rendered it possible to incorporate the simple stacked structure of Pt/TiN/poly-Si plug. When a $Pt-IrO_2$ hybrid electrode is applied, PZT thin film properties are influenced by the thickness and the partial coverage of the electrode layers. The optimized $Pt-IrO_2$ hybrid electrode significantly enhanced the fatigue properties of the PZT thin film with minimal leakage current.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.149.1-149.1
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• 2013

Noble metal silicides are widely used in silicon based microelectronic and optoelectronic devices. Among them, as compared to other silicides, structural and electronic properties of platinum silicide (PtSi) are found to be less sensitive to change in its dimensions. PtSi is known to overcome the junction spiking problems of Al-Si contacts. Present study is regarding the spatial evolution of platinum silicide in Pt/SiOx/Si. Scanning photoelectron emission microscopy (SPEM) was used for this purpose. SPEM images were obtained for pristine samples and after an annealing at $500^{\circ}C$ for 1 hr. Core-level spectra were recorded at different points in SPEM images contrasted by the intensity of Pt 4f7/2. Both Pt 4f and Si 2p spectra reveal the formation of PtSi after annealing. However, in contrast to earlier reports, PtSi formation is found to be non-uniform confirmed by the SPEM images and from the core level spectra taken at different intensity points.

• 한국토양비료학회지
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• 제20권1호
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• pp.85-88
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• 1987

상수리나무에 대한 모래밭버섯균(Pt)와 알버섯균(Rr)의 접종효과(接種效果) 및 적정(適正) Pt 접종량(接種量)을 구명(究明)코저 토양소독(土壤消毒)을 실시(實施)하고 균근균(菌根菌)을 접종(接種)한 결과(結果)는 다음과 같다. 1. 균근형성율(菌根形成率)은 생장(生長) 2년차(年次)에 Pt가 최고(最高) 42%, Rr이 36%로 비교적 낮았으나 1년차(年次)에는 높았을 것으로 생각된다. 2. 상수리나무묘목(苗木)의 생장(生長)은 토양소독구(土壤消毒區)에서 우세하였으며 특히 Pt 배량접종구(倍量接種區)가 가장 좋았다. 3. Rr 접종구(接種區)는 Pt 접종구(接種區)와 비슷한 생장(生長)을 하여 Rr 균(菌)의 접종효과(接種效果)가 나타났다. 4. 토양소독후(土壤消毒後) 균접종(菌接種)으로 지하부(地下部) 중량(重量)이 크게 증가(增加)하였으며 따라서 조림후(造林後) 활착율증대(活着率增大)가 기대된다. 그러나 토양무소독구(土壤無消毒區)에서는 균접종효과(菌接種效果)가 뚜렷하지 않았음. 5. 엽내양분함량(葉內養分含量)은 N과 $P_2O_5$에서 처리간(處理間)의 차(差)없이 상당히 높았고 $K_2O$와 CaO는 토양소독접종구(土壤消毒接種區)가 높아 균접종(菌接種)에 의한 양분흡수(養分吸收) 효과(效果)가 인정(認定)되었다.