• 제목/요약/키워드: Electron Flow

검색결과 675건 처리시간 0.024초

전자 흐름에 기초한 기초적인 화학 반응에 관한 대학생들의 이해도 조사 (Investigation of Undergraduate Students' Understanding on Fundamental Chemical Reaction Based on Electron Flow)

  • 이상권;권정균;김경미;박국태
    • 대한화학회지
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    • 제46권3호
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    • pp.279-286
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    • 2002
  • 이 연구의 목적은 대학생들이 유기화학 반응을 전자의 흐름으로 이해하는데 필요한 기초 지식에 대하여 어떤 선개념을 가지고 있으며, 기초적인 화학 반응을 전자의 흐름으로 이해하는 능력은 어느 정도인지 조사하여 교수 학습 방법에 도움을 주고자 하는데 있다. ?見?위해 H 대학교 화학교육과 2학년 18명을 연구 대상으로 선정하였고, 선행연구에서 밝혀진 연구결과를 근거로 하여 예비검사를 거쳐 검사도구를 개발하였다. 개발된 검사도구로 지필검사를 실시하여 대학생들의 응답을 통계처리 하였고, 통계적인 의미를 정성적으로 확인하기 위하여 면담을 실시하였다. 연구 결과, 대학생들의 원자의 전자배치에 대한 개념과 전자의 흐름에 기초하여 화학 반응을 이해하는데 필요한 기본 개념들에 대한 이해도는 높았으나, 이 개념들을 기초적인 화학 반응에 적용시키지는 못하였다. 그러므로 전자의 흐름에 기초하여 화학 반응을 이해하는데 필요한 기본 개념들을 화학 반응에 적용할 수 있게 하는 교수 학습 전략의 개발이 필요하다.

고주파 유도방전 플라즈마의 푸로우브법에 의한 계측 (A Measurements of Radio-Frequency Induction Discharge Plasma using probe method)

  • 박성근;박상윤;하장호;박원주;이광식;이동인
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1997년도 하계학술대회 논문집 E
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    • pp.1657-1659
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    • 1997
  • Electron temperature and electron density were measured in a radio-frequency inductively coupled plasma (RFICP) using a probe measurements. Measurement was conducted in an argon discharge for pressures from 10 [mTorr] to 40 [mTorr] and input rf power from 100 [W] to 800 [W], Ar flow rate from 5 [sccm] to 30 [sccm], Spatial distribution electron temperature and electron density were measured for discharge with same aspect ratio (R/L=2). Electron temperature and electron density were discovered depending on both pressure and power, Ar flow rate. Electron density was increased with increasing input power and in creasing pressure, increasing Ar flow rate. Radial distribution of the electron density was peaked in the plasma center. Normal distribution of the electron density was peaked in the center between quartz plate and substrate. From these results, We found out the generation mechanism of Radio-Frequency Inductively Coupled Plasma.

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고주파 유도결합 플라즈마의 전자에너지 분포함수 특성에 관한 연구 (A Study on the characteristics of Electron Energy Distribution function of the Radio-Frequency Inductively Coupled Plasma)

  • 황동원;하장호;전용우;최상태;이광식;박원주;이동인
    • 한국조명전기설비학회:학술대회논문집
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    • 한국조명전기설비학회 1998년도 학술발표회논문집
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    • pp.131-133
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    • 1998
  • Electron temperature, electron density and electron energy distribution function were measured in Radio-Frequency Inductively Coupled Plasma(RFICP) using a probe method. Measurements were conducted in argon discharge for pressure from 10 mTorr to 40 mTorr and input rF power from 100W to 600W and flow rate from 3 sccm to 12 sccm. Spatial distribution of electron temperature, electron density and electron energy distribution function were measured for discharge with same aspect ratio (R/L=2). Electron temperature was found to depend on pressure, but only weakly on power. Electron density and electron energy distribution function strongly depended on both pressure and power. Electron density and electron energy distribution function increased with increasing flow rate. Radial distribution of the electron density and electron energy distribution function were peaked in the plasma center. Normal distribution of the electron density, electron energy distribution function were peaked in the center between quartz plate and substrate. These results were compared to a simple model of ICP, finally, we found out the generation mechanism of Radio-Frequency Inductively Coupled Plasma.

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연속식 흐름 가스상물질의 전자선 분해반응에서 전류 세기가 반응효율 및 kinetics에 미치는 영향 (Effects of Current Intensity on the Reaction Efficiency and Kinetics of Gas Compound Decomposition by Electron Beam in a Continuous Flow System)

  • 김탁현;김동우;조상희;손지은;유승호;김태훈;박종석
    • 방사선산업학회지
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    • 제18권3호
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    • pp.235-240
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    • 2024
  • Electron beam technology has recently attracted attention as one of the powerful air pollution control methods. In this study, methyl mercaptan decomposition by electron beam in a continuous gas flow system was studied. To this, the effect of gas flowrate, which is one of important operating variables in the continuous gas flow electron beam process, on methyl mercaptan treatment efficiency was studied. In particular, the treatment efficiency and the reaction kinetics of methyl mercaptan decomposition were compared when calculated based on the absorbed dose and when calculated based on the current intensity of electron beam. When based on the electron beam absorbed dose, the treatment efficiency and 1st-order reaction constant increased as the gas flowrate was increased, contrary to the trends in general chemical reactions. However, when based on the current intensity, the treatment efficiency and 1st-order reaction constant increased as the gas flowrate was decreased, which can be theoretically explained. This is due to the fact that the current intensity increased as the gas flowrate was increased, resulting in improved the electron beam treatment efficiency. In conclusion, it is necessary to consider not only the absorbed dose but also the current intensity of electron beam in order to explain the results of reaction efficiencies and kinetics in the continuous flow electron beam gas treatment process.

Surface Plasmon Effect in Hot Electron Based Photovoltaic Devices

  • 이영근;정찬호;박종혁;박정영
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2011년도 제41회 하계 정기 학술대회 초록집
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    • pp.162-162
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    • 2011
  • Nanometer-sized noble metals can trap and guide sunlight for enhanced absorption of light based on surface plasmon that is beneficial for generation of hot electron flows. A pulse of high kinetic energy electrons (1-3 eV), or hot electrons, in metals can be generated after surface exposure to external energy, such as in the absorption of light or in exothermic chemical processes. These energetic electrons are not at thermal equilibrium with the metal atoms. It is highly probable that the correlation between hot electron generation and surface plasmon can offer a new guide for energy conversion systems [1-3]. We show that hot electron flow is generated on the modified gold thin film (<10 nm) of metal-semiconductor (TiO2) Schottky diodes by photon absorption, which is amplified by localized surface plasmon resonance. The short-circuit photocurrent obtained with low energy photons (lower than bandgap of TiO2, ~3.1-3.2 eV) is consistent with Fowler's law, confirming the presence of hot electron flows. The morphology of the metal thin film was modified to a connected gold island structure after heating to 120, 160, 200, and 240$^{\circ}C$. These connected island structures exhibit both a significant increase in hot electron flow and a localized surface plasmon with the peak energy at 550-570 nm, which was separately characterized with UV-Vis [4]. The result indicates a strong correlation between the hot electron flow and localized surface plasmon resonance with possible application in hot electron based solar cells and photodetectors.

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산소 유량별 플라즈마 방출광원 세기에 따른 전자온도 진단과 산화주석박막 특성연구 (Study on Electron Temperature Diagnostic and the ITO Thin Film Characteristics of the Plasma Emission Intensity by the Oxygen Gas Flow)

  • 박혜진;최진우;조태훈;윤명수;권기청
    • 한국표면공학회지
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    • 제49권1호
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    • pp.92-97
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    • 2016
  • The plasma has been used in various industrial fields of semiconductors, displays, transparent electrode and so on. Plasma diagnostics is critical to the uniform process and the product. We use the electron temperature of the various plasma parameters for the diagnosis of plasma. Generally, the range of the electron temperature which is used in a semiconductor process used the range of 1 eV to 10 eV. The difference of electron temperature of 0.5 eV has a influence in plasma process. The electron temperature can be measured by the electrical method and the optical method. Measurement of electron temperature for various gas flow rates was performed in DC-magnetron sputter and Inductively Coupled Plasma. The physical properties of the thin film were also determined by changing electron temperatures. The transmittance was measured using the integrating sphere, and wavelength range was measured at 300 ~ 1100 nm. We obtain the thin film of the mobility, resistivity and carrier concentration using the hall measurement system. As to the electron temperature increase, optical and electrical properties decrease. We determine it was influenced by the oxygen flow ratio and plasma.

고주파 유도결합 플라즈마의 전자에너지 분포 계측 (II) (Measurement of Electron Energy Distribution of the Radio-Frequency Inductively Coupled Plasma)

  • 황동원;하장호;전용우;최상태;박원주;이광식;이동인
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 하계학술대회 논문집 E
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    • pp.1803-1805
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    • 1998
  • Electron temperature, electron density and electron energy distribution function were measured in Radio-Frequency Inductively Coupled Plasma(RFICP) using a probe method. Measurements were conducted in argon discharge for pressure from 10 mTorr to 40 mTorr and input rf power from 100W to 600W and flow rate from 3 sccm to 12 sccm. Spatial distribution electron temperature and electron density and electron energy distribution function were measured for discharge with same aspect ratio(R/L=2). Electron temperature was found to depend on pressure, but only weakly on power. Electron density and electron energy distribution function strongly depended on both pressure and power. Electron density and electron energy distribution function increased with increasing flow rate. Radial distribution of the electron density and electron energy distribution function were peaked in the plasma center. Normal distribution of the electron density electron energy distribution function were peaked in the center between quartz plate and substrate. These results were compared to a simple model of ICP, then we found out the generation mechanism of Radio-Frequency Inductively Coupled Plasma.

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비탄성 변형이론을 이용한 $Fe_3$Al 금속간화합물의 소성변형 기구 고찰 (A Study of Plastic Deformation Mechanisms in $Fe_3$Al Intermetallics Alloys by Inelastic Deformation Theory)

  • 정호철
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 1999년도 춘계학술대회논문집
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    • pp.180-183
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    • 1999
  • It is well known that Fe3Al intermetallic compound shows an anomalous peak of the yield strength at about 50$0^{\circ}C$ and then decrease at higher temperatures The dislocation structure was examined by transmission electron microscopy and high temperatures. The dislocation structure was examined by transmission electron microscopy and high temperature mechanical properties were examined by tensile and load relaxation tests. The flow stress curves obtained from load relaxation tests were then analyzed in terms of internal variable deformation theory. it was found that the flow curves consisted of three micro-deformation mechanisms -i. e inelastic deformation mode plastic deformation mode and dislocation creep deformation mode depending on both dislocation structure and deformation temperature. The flow curves could be well described by the constitutive equations of these three micro-deformation mechanisms based on the internal variable deformation theory.

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UNDERLIGNING THERMOCAPILLARY EFFECTS BY ELECTRON BEAM MELTING OF THIN SPECIMENS

  • Domergue, L.;Camel, D.;Marya, S.
    • 대한용접접합학회:학술대회논문집
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    • 대한용접접합학회 2002년도 Proceedings of the International Welding/Joining Conference-Korea
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    • pp.199-204
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    • 2002
  • Extensive investigations on cast to cast variations observed in steels have underlined the role of thermocapillary or surface tension driven fluid flow in welding operations. The behavior of weld pool under the electric arc is however affected by possible arc modifications linked to microchemistry variations in materials & this limits to some extent the real contribution from surface tension effects. Thus, electron beam welding with high vacuum was used to investigate thermo-capillary effects on thin austenitic stainless steels & nickel based alloys. The weld pool was monitored by video observations to estimate the importance of fluid flow during the melting & solidification phase. The results underline the importance of fluid flow on [mal solidification.

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Stimulation of Blood Flow Needs a Parallel Magnetic Field and Psycho-physics acupuncture

  • Oh, Hung-Kuk
    • 한국감성과학회:학술대회논문집
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    • 한국감성과학회 2000년도 추계학술대회 논문집
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    • pp.105-112
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    • 2000
  • The conventional model did not take momentum conservation into consideration when the electron absorbs and emits the photons. II-ray provides momentum conservations on any directions of the entering photons, and also the electrons have radial momentum conservations and fully elastic bouncing between two atoms, in the new atom model. Conventional atom model must be criticized on the following four points. (1) Natural motions between positive and negative entities are not circular motions but linear going and returning ones, fur examples sexual motion, tidal motion, day and night etc. Because the radius of hydrogen atom's electron orbit is the order of 10$^{-11}$ m and the radia of the nucleons in the nucleus are the order of 10$^{-l4}$m and then the converging $\pi$-gamma rays to the nucleus have so great circular momentum, the electron can not have a circular motion. We can say without doubt that any elementary mass particle can have only linear motion, because of the $\pi$-rays' hindrances, near the nucleus. (2) Potential energy generation was neglected when electron changes its orbit from outer one to inner one. The h v is the kinetic energy of the photo-electron. The total energy difference between orbits comprises kinetic and potential energies. (3) The structure of the space must be taken into consideration because the properties of the electron do not change during the transition from outer orbit to inner one even though it produces photon. (4) Total energy conservation law applies to the energy flow between mind and matter because we daily experiences a interconnection between mind and body. Any magnet absorbs n-rays to S pole and sends out the $\pi$-rays from N pole. Proton are constructed with the closed n-rays quantum-mechanically. The crystallizing n-bonding makes two $\pi$-far infrared rays of one wave length between two protons if two $\pi$-rays are supplied to each proton. It is easily done for a $\pi$-ray to be absorbed to a proton if there is a parallel magnetic flow to the blood flow because a $\pi$-ray advances axially under a magnetic field and a proton looks like a sphere. A axially advancing disk-like $\pi$-ray can meet more easily the coming spheres than from the other directions. The blood crystals stimulate the autonomous nerves on the blood vessels during the flow by their mechanical sliding collisions. SM n-ray meridian therapy and SMACN $\pi$-ray meridian therapy show the stimulation of blood flow and also combinational experiment between SM $\pi$-ray meridian therapy and n-ray psycho-physics acupuncture shows more clearly that magnet is forcing to make $\pi$-rays absorbed to the nucleons.s.ons.

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