• 제목/요약/키워드: Metallic Bi

검색결과 61건 처리시간 0.023초

반사광 측정 모드에서 금과 은을 사용한 이층 금속 칩과 삼층 금속 칩의 특성 연구 (Characteristics of Gold and Silver Based Bi- and Tri-metallic SPR Chip in the Intensity Measurement Mode)

  • 김형진;김창득;손영수
    • 센서학회지
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    • 제25권2호
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    • pp.143-147
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    • 2016
  • Characteristics of the conventional gold (Au) surface plasmon resonance (SPR) chip, bi-metallic(Au/silver (Ag)) SPR chip, and tri-metallic(Au/Ag/Au) SPR chip were investigated and compared in the intensity measurement mode for the enhancement of SPR image sensor reactivity. Reflectance curves of the Au, bi- and tri-metallic SPR chips were acquired in phosphate-buffered saline (PBS) solution and were compared. The line width of the reflectance curve of the bi-metallic chip was the narrowest among the three different types of the chips. Also, the tangential slope of the bi-metallic chip was steeper than those of the other chips. Various concentrations of bovine serum albumin (BSA) were utilized in the SPR experiment. As a result, among the above three chips reflectance variation value of the bi-metallic chip was the largest.

Numerical Study of a Novel Bi-focal Metallic Fresnel Zone Plate Having Shallow Depth-of-field Characteristics

  • Kim, Jinseob;Kim, Juhwan;Na, Jeongkyun;Jeong, Yoonchan
    • Current Optics and Photonics
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    • 제2권2호
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    • pp.147-152
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    • 2018
  • We propose a novel bi-focal metallic Fresnel zone plate (MFZP) with shallow depth-of-field (DOF) characteristics. We design the specific annular slit patterns, exploiting the phase-selection-rule method along with the particle swarm optimization algorithm, which we have recently proposed. We numerically investigate the novel characteristics of the bi-focal MFZP in comparison with those of another bi-focal MFZP having equivalent functionality but designed by the conventional multi-zone method. We verify that whilst both bi-focal MFZPs can produce dual focal spots at $15{\mu}m$ and $25{\mu}m$ away from the MFZP plane, the former exhibits characteristics superior to those of the latter from the viewpoint of axial resolution, including the axial side lobe suppression and axial DOF shallowness. We expect the proposed bi-focal MFZP can readily be fabricated with electron-beam evaporation and focused-ion-beam processes and further be exploited for various applications, such as laser micro-machining, optical trapping, biochemical sensing, confocal sensing, etc.

두 방향 주름구조를 내부구조로 하는 금속 샌드위치 판재의 제작 및 성형 (Fabrication and forming of metallic sandwich plates with bi-directional corrugated inner structure)

  • 성대용;정창균;심도식;양동열;김지용;김종호;정완진
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2006년도 춘계학술대회 논문집
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    • pp.281-284
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    • 2006
  • Metallic sandwich plates with hi-directional inner structure are important new structures for forming applications. Bi-directional corrugated inner structures with less than 25% of relative density are fabricated by piecewise sectional forming process and then bonded with two face sheets by adhesive bonding. Drawing and U-bending experiments have performed and shown that the radius of curvature of sandwich plates is 75mm and sandwich plates are bended 90 degrees without collapse of inner structures. Bi-directional inner structures are suggested to improve formability of sandwich plates for bending and drawing.

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On-Film Formation of Nanowires for High-efficiency Thermoelectric Devices

  • Ham, Jin-Hee;Shim, Woo-Young;Lee, Seung-Hyun;Voorhees, Peter W.;Lee, Woo-Young
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2009년도 춘계학술대회 논문집
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    • pp.17-17
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    • 2009
  • We report the invention of a direct growth method termed On-Film Formation of Nanowire (OFF-ON) for making high-quality single-crystal nanowires, i.e. Bi and $Bi_2Te_3$, without the use of conventional templates, catalysts, or starting materials. We have used the OFF-ON technique to grow single crystal semi-metallic Bi and compound semiconductor $Bi_2Te_3$ nanowires from sputtered Bi and BiTe films after thermal annealing, respectively. The mechanism for nanowire growth is stress-induced mass flow along grain boundaries in the polycrystalline films. OFF-ON is a simple but powerful method for growing perfect single-crystal semi-metallic and compound semiconductor nanowires of high aspect ratio with high crystallinity that distinguishes it from other competitive growth approaches that have been developed to date. Our results suggest that Bi and $Bi_2Te_3$ nanowires grown by OFF-ON can be an ideal material system for exploring their unique thermoelectric properties due to their high-quality single crystalline and high conductivity, which have consequence and relevance for high-efficiency thermoelectric devices.

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Targeted alpha therapy (TAT) for cancer using metallic radioisotopes

  • Kang, Chi Soo;Lee, Kyo Chul;Lee, Yong Jin
    • 대한방사성의약품학회지
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    • 제5권2호
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    • pp.135-144
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    • 2019
  • Targeted alpha therapy (TAT) based on metallic radionuclides has attracted a lot of attention lately due to its impressive therapeutic efficacy displayed in couple of clinical studies for cancer. Representative metallic radionuclides emitting alpha-particle include 225Ac, 213Bi, and 227Th, and there have been variety of TAT formulations based on different targeting moiety and chelating agents. In this review, we introduce strategies to label metallic radioisotopes with biomolecules and look at some of recent preclinical and clinical results of TAT for cancer.

粗鉛의 乾式 脫蒼鉛에 관한 基礎的 硏究 (A Fundamental Study on the Pyrometallurgical Debismuthizing of Lead)

  • 고창식
    • 대한화학회지
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    • 제6권2호
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    • pp.143-147
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    • 1962
  • As a part of "the Fundamental Study of Pyrometallurgical Debismuthizing of Lead", the author has studied liquid Pb-Bi, Pb-Na, Bi-Na binaries and Pb-Bi-Na ternary including Pb rich side composition which forms a basis of the Dittmer method. In this study, debismuthizing mechanism of the Dittmer method pertaining to the lead rich corner of the system studied was classified by the results of thermal analysis, solubility determination of Bi and Na in liquid Pb and debismuthizing test by adding metallic sodium. For instance eutectic trough in lead rich corner of Pb-Bi-Na ternary relating to the Dittmer method was determined.

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고 탄화수소 개질을 위한 Pt-Ru, Pt-Ni 이원금속촉매에 관한 연구 (Pt-Ru, Pt-Ni bi-metallic catalysts for heavy hydrocarbon reforming)

  • 이상호;배중면
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2011년도 추계학술대회 초록집
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    • pp.97.2-97.2
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    • 2011
  • Pt-Ru and Pt-Ni bimetallic catalysts were prepared and tested for heavy hydrocarbon reforming. Metals were supported on CGO($Ce_{0.8}Gd_{0.2}O_{2.0-x}$) by incipient wetness method. The prepared catalysts were characterized by Temperature programmed reduction(TPR). Oxidative steam reforming of n-dodecane was conducted to compare the activity of the catalysts. The reforming temperature was varied from $500^{\circ}C$ to $800^{\circ}C$ at fixed $O_2$/C of 0.3, $H_2O$/C of 3.0 and GHSV of 5,000/h.Reduction peaks of metal oxide, surface CGO and bulk CGO were detected. Reduction temperature of metal oxide decreased over the bi-metallic catalysts. It is considered that interaction between metals leads to decrease interaction between metal and oxygen. On the other hands, reduction temperatures of surface CGO were dectected in the order of Pt-Ru > Pt-Ni > Pt. low reduction temperatures of surface CGO indicates the low activation energy for oxygen ion conduction to metal. Oxygen ion conduction is known as de-coking mechanism of ionic conducting supports such as CGO. In activity test, fuel conversion was in the same order of Pt-Ru > Pt-Ni > Pt. Especially, 100% of fuel conversion was obtained over Pt-Ru catalysts at $500^{\circ}C$.

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MAGNETOTRANSPORT OF SEMIMETALLIC Bi THIN FILMS CROWN BY ELECTROPLATING AND SPUTTERING

  • M. H. Jeon;Lee, K. I.;Lee, K. H.;J. Y. Chang;K. H. Shin;S. H. Han;Lee, W. Y.;J. G. Ha
    • 한국자기학회:학술대회 개요집
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    • 한국자기학회 2002년도 동계연구발표회 논문개요집
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    • pp.150-151
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    • 2002
  • In recent years, semi-metallic Bismuth (Bi) has attracted significant attention due to very large magnetoresistance (MR) at room temperature originating from long carrier mean free path l and small effective carrier mass m*[1, 2]. In particular, the MR behavior and long carrier mean free path l in Bi thin films can be exploited for spintronic devices, e.g. magnetic field sensors and spin-valve transistors. In present work, we present the magnetotransport properties of the electroplated and sputtered Bi thin films in the temperature range 4-300 K. (omitted)

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Irreversibly Adsorbed Tri-metallic PtBiPd/C Electrocatalyst for the Efficient Formic Acid Oxidation Reaction

  • Sui, Lijun;An, Wei;Rhee, Choong Kyun;Hur, Seung Hyun
    • Journal of Electrochemical Science and Technology
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    • 제11권1호
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    • pp.84-91
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    • 2020
  • The PtBi/C and PtBiPd/C electrocatalysts were synthesized via the irreversible adsorption of Pd and Bi ions precursors on commercial Pt/C catalysts. XRD and XPS revealed the formation of an alloy structure among Pt, Bi, and Pd atoms. The current of direct formic acid oxidation (Id) increased ~ 8 and 16 times for the PtBi/C and PtBiPd/C catalysts, respectively, than that of commercial Pt/C because of the electronic, geometric, and third body effects. In addition, the increased ratio between the current of direct formic acid oxidation (Id) and the current of indirect formic acid oxidation (Iind) for the PtBi/C and PtBiPd/C catalysts suggest that the dehydrogenation pathway is dominant with less CO formation on these catalysts.