• 제목/요약/키워드: Oxide addition

검색결과 2,429건 처리시간 0.03초

공정 Mg-Ni계 합금 분말의 제조 및 수소저장 특성 (Fabrication and hydrogen storage property of eutectic Mg-Ni based alloy powder)

  • 홍성현;배종수;임창동;나영상;송명엽
    • 한국수소및신에너지학회논문집
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    • 제17권2호
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    • pp.174-180
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    • 2006
  • The eutectic Mg-23.5%Ni alloy was casted by melting and solidification. The powders of Mg-23.5%Ni and (Mg-23.5%Ni)-10% iron oxide were prepared by mechanical grinding of casted Mg-Ni alloy and casted Mg-Ni alloy+oxide, respectively. As milling time increases, hydriding and dehydriding rates of Mg-Ni and Mg-Ni-oxide alloy powders increase. The additions of iron oxide to Mg-Ni alloy and Mg-Ni-oxide increase hydriding rates and slightly decrease dehydriding rates.

Role of Angiotensin II and Nitric Oxide in the Rat Paraventricular Nucleus

  • Yang, Eun-Kyoung
    • The Korean Journal of Physiology and Pharmacology
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    • 제5권1호
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    • pp.41-46
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    • 2001
  • To investigate the mutual relationship between angiotensin II (Ang II) and nitric oxide (NO) in paraventricular nucleus (PVN), Ang II receptor type Ia $(AT_{1A}),$ type Ib $(AT_{1B}),$ endothelial constitutive nitric oxide synthase (ecNOS), and neuronal constitutive nitric oxide synthase (ncNOS) mRNA levels of rat PVN were measured after unilateral carotid artery ligation. $AT_{1A}$ and $AT_{1B}$ mRNA levels were markedly elevated 6 hrs after unilateral carotid artery ligation. Losartan injection $(10\;{\mu}g/0.3\;{\mu}l)$ into the PVN augmented of the increment of $AT_{1A}$ and $AT_{1B}$ mRNAs It also increased ecNOS gene expression. In addition, $AT_{1B}$ mRNA levels increased after N-nitro-L-arginine methyl ester (L-NAME) injection $(50\;{\mu}g/0.3\;{\mu}l)$ into the PVN. These results suggest that Ang II and NO in the rat PVN may interplay, at least in part, through regulation of gene expression of ecNOS and $AT_{1B},$ respectively.

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Tapering과 Ferroelectric Polarization에 의한 3D NAND Flash Memory의 Lateral Charge Migration 분석 (The Analysis of Lateral Charge Migration at 3D-NAND Flash Memory by Tapering and Ferroelectric Polarization)

  • 이재우;이종원;강명곤
    • 전기전자학회논문지
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    • 제25권4호
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    • pp.770-773
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    • 2021
  • 본 논문에서는 tapering과 ferroelectric(HfO2)구조가 적용된 3D NAND flash memory의 프로그램 이후 시간경과에 따른 retention특징을 분석했다. Nitride에 trap된 전자는 시간이 지남에 따라 lateral charge migration이 발생한다. 프로그램 이후 시간이 지남에 따라 trap된 전자가 tapering에 의해 두꺼워진 채널 쪽으로 lateral charge migration이 더 많이 발생하는 것을 확인했다. 또한 Oxide-Nitride-Ferroelectric (ONF) 구조는 polarization에 의해 lateral charge migration이 완화되기 때문에 기존 Oxide-Nitride-Oxide (ONO) 구조 보다 문턱전압(Vth)의 변화량이 줄어든다.

Fabrication of IGZO-based Oxide TFTs by Electron-assisted Sputtering Process

  • 윤영준;조성환;김창열;남상훈;이학민;오종석;김용환
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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    • pp.273.2-273.2
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    • 2014
  • Sputtering process has been widely used in Si-based semiconductor industry and it is also an ideal method to deposit transparent oxide materials for thin-film transistors (TFTs). The oxide films grown at low temperature by conventional RF sputtering process are typically amorphous state with low density including a large number of defects such as dangling bonds and oxygen vacancies. Those play a crucial role in the electron conduction in transparent electrode, while those are the origin of instability of semiconducting channel in oxide TFTs due to electron trapping. Therefore, post treatments such as high temperature annealing process have been commonly progressed to obtain high reliability and good stability. In this work, the scheme of electron-assisted RF sputtering process for high quality transparent oxide films was suggested. Through the additional electron supply into the plasma during sputtering process, the working pressure could be kept below $5{\times}10-4Torr$. Therefore, both the mean free path and the mobility of sputtered atoms were increased and the well ordered and the highly dense microstructure could be obtained compared to those of conventional sputtering condition. In this work, the physical properties of transparent oxide films such as conducting indium tin oxide and semiconducting indium gallium zinc oxide films grown by electron-assisted sputtering process will be discussed in detail. Those films showed the high conductivity and the high mobility without additional post annealing process. In addition, oxide TFT characteristics based on IGZO channel and ITO electrode will be shown.

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Preparation and Properties of Silicone Hydrogel Material Containing Silane Group with Cobalt Oxide Nanoparticles through Thermal Polymerization

  • Lee, Min-Jae;Kong, Ki-Oh;Sung, A-Young
    • 한국재료학회지
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    • 제30권6호
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    • pp.273-278
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    • 2020
  • This research is conducted to analyze the compatibility of used monomers and produce the high functional hydrogel ophthalmic polymer containing silane and nanoparticles. VTMS (vinyltrimethoxysilane), TAVS [Triacetoxy(vinyl)silane] and cobalt oxide nanoparticles are used as additives for the basic combination of SilM (silicone monomer), MMA (methyl methacrylate) and MA (methyl acrylate). Also, the materials are copolymerized with EGDMA (ethylene glycol dimethacrylate) as cross-linking agent, AIBN (thermal polymerization initiator) as the initiator. It is judged that the lenses of all combinations are optically excellent and thus have good compatibility. Measurement of the optical and physical characteristics of the manufactured hydrophilic ophthalmic polymer are different in each case. Especially for TAVS, the addition of cobalt oxide nanoparticles increases the oxygen permeability. These materials are considered to create synergy, so they can be used in functional hydrogel ophthalmic lenses.

Is Nitric Oxide Involved in Relaxation of Urinary Bladder\ulcorner

  • Chang, Ki-Churl;Chung, Byung-Ha
    • Biomolecules & Therapeutics
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    • 제3권1호
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    • pp.58-62
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    • 1995
  • We investigated whether nitric oxide (NO) may serve a role in bladder function by immunohistochemical analysis of the distribution of intrinsic NADPH-diaphorase and functional study of isometric tension recordings via a photo-induced adequate nitric oxide (PIANO) generating system using rat bladder. Results suggest that a small number of NADPH-diaphorase-positive perikarya are present within the bladder wall and within adjacent small ganglia. Furthermore, NADPH-diaphorase-positive nerve fibers were observed in the adventitial and muscular layers, subjacent to the urothelium and perivascular fibers. Rat bladder strips precontracted with 3$\mu$M carbachol were reversibly relaxed upon NO generation by UV irradiation. PIANO-mediated relaxation was sensitive to oxygen free radicals. In addition, tissue cGMP levels were increased by the PIANO generating system and elevated cGMP levels were decreased by pretreatment of guanylate cyclase inhibitor, methylene blue. These results indicate that NO may serve a role in modulating bladder tone in the rat.

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텅스텐 첨가에 의한 적외선 소자용 바나듐 옥사이드의 특성 향상 (Improvement of bolometric properties of vanadium oxide by addition of tungsten)

  • 한용희;최인훈;김근태;신현준;치엔;문성욱
    • 한국재료학회:학술대회논문집
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    • 한국재료학회 2003년도 추계학술발표강연 및 논문개요집
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    • pp.207-207
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    • 2003
  • Uncooled infrared(IR) detectors that use a microbolometer with a large focal-plane array(FPA) have been developed with surface micromachining technology. There are many materials for microbolometers, such as metals, vanadium oxide, semiconductors and superconductors. Among theses, vanadium oxide is a promising material for uncooled microbolometers due to it high temperature coefficient of resistance(TCR) at room temperature. It is, however, is very difficult to deposit vanadium oxide thin films having a high TCR and low resistance because of the process limits in microbolometer fabrication. In general, vanadium oxides have been applied to microbolometer in mixed phases formed by ion beam deposition methods at low temperature with TCR in the range from -1.5 to -2.0%K.

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Measurements of fractional exhaled nitric oxide in pediatric asthma

  • Hahn, Youn-Soo
    • Clinical and Experimental Pediatrics
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    • 제56권10호
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    • pp.424-430
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    • 2013
  • Exhaled nitric oxide (NO) has been extensively investigated as a noninvasive marker of airway inflammation in asthma. The increased NO expression induced by inflammatory mediators in airways can be monitored easily in exhaled air from asthmatic children. Based on the relationship between the increased NO expression and eosinophilic airway inflammation, fractional exhaled nitric oxide (FeNO) measurements become an important adjunct for the evaluation of asthma. In addition, the availability of portable devices makes it possible to measure FeNO more easily and frequently in the routine pediatric practice. Despite various confounding factors affecting its levels, FeNO can be applicable in diagnosing asthma, monitoring treatment response, evaluating asthma control, and predicting asthma exacerbations. Thus, although pulmonary function tests are the standard tools for objective measurements of asthmatic control, FeNO can broaden the way of asthma monitoring and supplement standard clinical asthma care guidelines.

산화물환원에 의한 W-15wt%Cu 나노복합분말의 합성과 특성 (Synthesis and Characteristics of W-l5wt%Cu Nanocomposite Powder by Oxide Reduction)

  • 윤의식
    • 한국분말재료학회지
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    • 제4권4호
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    • pp.304-309
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    • 1997
  • The synthesis of W-l5wt%Cu nanocomposite powder by hydrogen reduction of ball milled W-Cu oxide mixture was investigated in terms of powder characteristics such as particle size, mixing homogeneity and micropore structure. It is found that the micropores in the ball milled oxide (2-50 nm in size) act as an effective removal path of water vapor, followed by the formation of dry atmosphere at reaction zone. Such thermodynamic condition enhances the nucleation of W phase but suppresses the growth process, being in favor of the formation of W nanoparticles (about 21 nm in size). In addition, the superior mixing homogeneity of starting oxide mixture turned out to Play a significant role for forming extraordinary chemical homogeneity of W-l5wt%Cu nanocomposite powder.

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Oxide TFT as an Emerging Technology for Next Generation Display

  • Kim, Hye-Dong;Jeong, Jae-Kyeong;Mo, Yeon-Gon;Chung, Ho-Kyoon
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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    • pp.119-122
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    • 2008
  • In this paper, we describe the current status and issues of the oxide thin-film transistors (OTFTs), which attract much attention as an emerging new backplane technology replacing conventional silicon-based TFTs technologies. First, the unique benefits of OTFTs will be presented as a backplane for large-sized AMOLED including note-book PC, second TV and HD-TV. And then, the state-of-the-art transistor performance and uniformity characteristics of OTFTs will be highlighted. The obtained a-IGZO TFTs exhibited the field-effect mobility of $18\;cm^2/Vs$, threshold voltage of 1.8 V, on/off ratio of $10^9$, and subthreshold gate swing of 0.28 V/decade. In addition, the world largest-sized 12.1-inch WXGA active-matrix organic light emitting diode (AMOLED) display is demonstrated using indium-gallium-zinc oxide (IGZO) TFTs.

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