• 제목/요약/키워드: Barrier factor

검색결과 450건 처리시간 0.029초

Electron Field Emission for a Cylindrical Emitter of Single Carbon Nanotube

  • Lee, Youn-Ju;Kim, Chang-Duk;Lee, Hyeong-Rag
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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    • pp.764-767
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    • 2007
  • We investigated the field emission of single carbon nanotube including the anode effect by calculating the tunneling probability of an electron. The experimental results from this study were in agreement with our theoretical calculations. The constant enhancement factor was calculated using an approximation of the potential barrier.

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체류 인자를 이용한, 알부민의 정량 분석용 종이 칩 (Diagnostic Paper Chip for Reliable Quantitative Detection of Albumin using Retention Factor)

  • 정성근;이상호;이창수
    • KSBB Journal
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    • 제28권4호
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    • pp.254-259
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    • 2013
  • Herein we present a diagnostic paper chip that can quantitatively detect albumin without external electronic reader and dispensing apparatus. We fabricated a diagnostic paper chip device by printing wax barrier on the paper and wicking it with citrate buffer and tetrabromophenol blue to detect albumin in sample solution. The paper chip is so simple that we dropped a sample solution at sample pad and measure the ratio of two travel distances of the sample solvent and albumin under the name of retention factor. Our result confirmed that the retention factor was constant in the samples with same concentration of albumin and useful determinant for the measurement of albumin concentration. The paper chip is affordable and equipment-free, and close to ideal point-of-care test in accordance with the assured criteria, outlined by the World Health Organization. We assume that this diagnostic paper chip will expand the concept of colorimetric determination and provide a inexpensive diagnostic method to aging society and developing country.

Effect of thermal conductivity degradation on the behavior of high burnup $UO_2$ fuel

  • Lee, Byung-Ho;Koo, Yang-Hyun;Sohn, Dong-Seong
    • 한국원자력학회:학술대회논문집
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    • 한국원자력학회 1996년도 춘계학술발표회논문집(3)
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    • pp.265-270
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    • 1996
  • The temperature distribution in the pellet was obtained from beginning the general heat conduction equation. The thermal conductivity of pellet used the SIMFUEL data that made clear the effect of burnup on the thermal conductivity degradation. Since the pellet rim acts as the thermal barrier to heat flow. the pellet was subdivided into several rings in which the outer ring was adjusted to play almost the same role as the rim. The local burup in each ring except the outer ring was calculated from the power depression factor based on FASER results. whereas the rim burnup at the outer ring was achieved by the pellet averaged burnup based on the empirical relation. The rim changed to the equivalent Xe film so the predicted temperature shooed the thermal jump across the rim. The observed temperature profiles depended on linear heat generation rate. fuel burnup. and power depression factor. The thermal conductivity degradation modelling can be applied to the fuel performance code to high burnup fuel,

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Novel host and electron blocking materials for efficient and long lifetime phosphorescent OLEDs

  • Vestweber, Horst;Gerhard, Anja;Kaiser, Joachim;Heil, Holger;Kroeber, Jonas;Pflumm, Christof;Stoessel, Philipp;Joosten, Dominik;Buesing, Arne;Fortte, Rocco;Parham, Amir;Boehm, Edgar
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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    • pp.925-927
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    • 2008
  • In order to improve the performance in green phosphorescent OLED devices, Merck has developed novel host and electron blocking materials. The newly developed host materials improve the device lifetime by a factor of 3. The newly developed electron blocking materials having not only electron but also exciton barrier properties increase the efficiency of the device by a factor of 1.4. Comparable results were achieved in phosphorescent red systems with further host materials.

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A New Scaling Theory for the Effective Conducting Path Effect of Dual Material Surrounding Gate Nanoscale MOSFETs

  • Balamurugan, N.B.;Sankaranarayanan, K.;Suguna, M.
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제8권1호
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    • pp.92-97
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    • 2008
  • In this Paper, we present a scaling theory for dual material surrounding gate (DMSGTs) MOSFETs, which gives a guidance for the device design and maintaining a precise subthreshold factor for given device parameters. By studying the subthreshold conducting phenomenon of DMSGTs, the effective conductive path effect (ECPE) is employed to acquire the natural length to guide the design. With ECPE, the minimum channel potential is used to monitor the subthreshold behavior. The effect of ECPE on scaling factor significantly improves the subthreshold swing compared to conventional scaling rule. This proposed model offers the basic designing guidance for dual material surrounding gate MOSFETs.

Brain metastasis in human epidermal growth factor receptor 2-positive breast cancer: from biology to treatment

  • Koo, Taeryool;Kim, In Ah
    • Radiation Oncology Journal
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    • 제34권1호
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    • pp.1-9
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    • 2016
  • Overexpression of human epidermal growth factor receptor 2 (HER2) is found in about 20% of breast cancer patients. With treatment using trastuzumab, an anti-HER2 monoclonal antibody, systemic control is improved. Nonetheless, the incidence of brain metastasis does not be improved, rather seems to be increased in HER2-positive breast cancer. The mainstay treatment for brain metastases is radiotherapy. According to the number of metastatic lesions and performance status of patients, radiosurgery or whole brain radiotherapy can be performed. The concurrent use of a radiosensitizer further improves intracranial control. Due to its large molecular weight, trastuzumab has a limited ability to cross the blood-brain barrier. However, small tyrosine kinase inhibitors such as lapatinib, has been noted to be a promising agent that can be used as a radiosensitizer to affect HER2-positive breast cancer. This review will outline general management of brain metastases and will focus on preclinical findings regarding the radiosensitizing effect of small molecule HER2 targeting agents.

Wet-work Exposure: A Main Risk Factor for Occupational Hand Dermatitis

  • Behroozy, Ali;Keegel, Tessa G.
    • Safety and Health at Work
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    • 제5권4호
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    • pp.175-180
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    • 2014
  • Wet-work can be defined as activities where workers have to immerse their hands in liquids for >2 hours per shift, or wear waterproof (occlusive) gloves for a corresponding amount of time, or wash their hands >20 times per shift. This review considers the recent literature on wet-work exposure, and examines wet-work as a main risk factor for developing irritant contact dermatitis of the hands. The aim of this paper is to provide a detailed description of wet-work exposure among specific occupational groups who extensively deal with water and other liquids in their occupations. Furthermore, it highlights the extent and importance of the subsequent adverse health effects caused by exposure to wet-work.

시차장벽식 무안경 다시점 입체디스플레이 시스템에서 수평방향의 시점 수 저하 없이 깊이방향의 자유도를 증가시키기 위한 혁신적 방법 (Innovative Method to Expand a Degree of Freedom of Observation in the Depth Direction without Losses of the Horizontal Number of Views in Autostereoscopic Multi-Views 3D Display System)

  • 이광훈;박민철
    • 한국통신학회논문지
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    • 제38C권10호
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    • pp.903-910
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    • 2013
  • 무안경방식 스테레오스코픽 3D 디스플레이 시스템은 수평, 깊이방향에 대한 관찰자유도가 안경방식에 비해 매우 좁다. 본 논문에서는 분할된 3중의 기울어진 시차장벽(TS-SPB)을 사용하여 무안경방식에서 수평방향의 시점수를 유지하면서도 깊이방향의 시역폭을 증가시키는 혁신적인 방법을 제안한다. 본 논의의 당위성은 실제와 유사한 환경에서의 전산모사를 통하여 검증되었다. 결과적으로 색분산이 없는 수평방향의 가용 최대 시점수는 $2^n$이며, 깊이방향의 시역폭은 단일 시차장벽(SPB)의 경우와 비교하여 3.36배 증가하였다.

ZnO-Bi2O3-Mn3O4-Co3O4 바리스터의 결함과 전기적 특성 (Defects and Electrical Properties of ZnO-Bi2O3-Mn3O4-Co3O4 Varistor)

  • 홍연우;이영진;김세기;김진호
    • 한국전기전자재료학회논문지
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    • 제25권12호
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    • pp.961-968
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    • 2012
  • In this study, we have investigated the effects of Mn and Co co-doping on defects, J-E curves and grain boundary characteristics of ZnO-$Bi_2O_3$ (ZB) varistor. Admittance spectra and dielectric functions show two bulk defects of $Zn_i^{{\cdot}{\cdot}}$ (0.17~0.18 eV) and $V_o^{\cdot}$ (0.30~0.33 eV). From J-E characteristics the nonlinear coefficient (${\alpha}$) and resistivity (${\rho}_{gb}$) of pre-breakdown region decreased as 30 to 24 and 5.1 to 0.08 $G{\Omega}cm$ with sintering temperature, respectively. The double Schottky barrier of grain boundaries in ZB(MCo) ($ZnO-Bi_2O_3-Mn_3O_4-Co_3O_4$) could be electrochemically single type. However, its thermal stability was slightly disturbed by ambient oxygen because the apparent activation energy of grain boundaries was changed from 0.64 eV at lower temperature to 1.06 eV at higher temperature. It was revealed that a co-doping of Mn and Co in ZB reduced the heterogeneity of the barrier in grain boundaries and stabilized the barrier against an ambient temperature (${\alpha}$-factor= 0.136).

이류체 노즐을 이용한 유전체장벽방전 플라즈마 가스의 OH 라디칼 생성 향상 (Enhancement of OH Radical Generation of Dielectric Barrier Discharge Plasma Gas Using Air-automizing Nozzle)

  • 박영식
    • 한국환경과학회지
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    • 제27권8호
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    • pp.621-629
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    • 2018
  • Many chemically active species such as ${\cdot}H$, ${\cdot}OH$, $O_3$, $H_2O_2$, hydrated $e^-$, as well as ultraviolet rays, are produced by Dielectric Barrier Discharge (DBD) plasma in water and are widely use to remove non-biodegradable materials and deactivate microorganisms. As the plasma gas containing chemically active species that is generated from the plasma reaction has a short lifetime and low solubility in water, increasing the dissolution rate of this gas is an important challenge. To this end, the plasma gas and water within reactor were mixed using the air-automizing nozzle, and then, water-gas mixture was injected into water. The dissolving effect of plasma gas was indirectly confirmed by measuring the RNO (N-Dimethyl-4-nitrosoaniline, indicator of the formation of OH radical) solution. The plasma system consisted of an oxygen generator, a high-voltage power supply, a plasma generator and a liquid-gas mixing reactor. Experiments were conducted to examine the effects of location of air-automizing nozzle, flow rate of plasma gas, water circulation rate, and high-voltage on RNO degradation. The experimental results showed that the RNO removal efficiency of the air-automizing nozzle is 29.8% higher than the conventional diffuser. The nozzle position from water surface was not considered to be a major factor in the design and operation of the plasma reactor. The plasma gas flow rate and water circulation rate with the highest RNO removal rate were 3.5 L/min and 1.5 L/min, respectively. The ratio of the plasma gas flow rate to the water circulation rate for obtaining an RNO removal rate of over 95% was 1.67 ~ 4.00.