• Title/Summary/Keyword: 이온화

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나노구조물의 자기조립화를 이용한 고용량 나노전기수력학

  • Park, Jeong-Yeol
    • Journal of the KSME
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    • v.57 no.10
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    • pp.48-52
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    • 2017
  • 이 글에서는 공간적으로 형상 제어된 나노구조물의 자기조립화(self-assembly)를 이용하여 고용량의 이온흐름이 가능한 나노전기수력학 기술에 대한 소개와 더불어, 이를 활용한 이온 다이오드, 고효율 마이크로 믹서, 이온농도차 발전 응용 및 향후 생체 내 이온검출 센서, 인체 삽입형 디바이스, 뇌-기계 인터페이스 연구에 대한 전망을 소개하고자 한다.

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Influence of Carbonation on the Chloride Diffusion in Concrete (탄산화 현상이 콘크리트 중의 염소이온 확산에 미치는 영향 연구)

  • Oh, Byung-Hwan;Lee, Sung-Kyu;Lee, Myung-Kue;Jung, Sang-Hwa
    • Journal of the Korea Concrete Institute
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    • v.15 no.6
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    • pp.829-839
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    • 2003
  • Recently, the corrosion of reinforced concrete structures has received great attention related with the deterioration of sea-side structures, such as new airport, bridges, and nuclear power plants. In this regards, many studies have been done on the chloride attack in concrete structures. However, those studies were confined mostly to the single deterioration due to chloride only, although actual environment is rather of combined type. The purpose of the present study is, therefore, to explore the influences of carbonation to chloride attack in concrete structures. The test results indicate that the chloride penetration is more pronounced than the case of single chloride attack when the carbonation process is combined with the chloride attack. It is supposed that the chloride ion concentration of carbonation region is higher than the sound region because of the separation of fixed salts. Though the use of fly ash pronounces the chloride ion concentration in surface, amounts of chloride ion penetration into deep region decreases with the use of fly ash. The present study allows more realistic assessment of durability for such concrete structures which are subjected to combined attacks of both chlorides and carbonation but the future studies for combined environment will assure the precise assessment.

레이저 변수가 마그네슘 원자의 다광자 이온화에 미치는 영향 연구

  • 김달우
    • Proceedings of the Optical Society of Korea Conference
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    • 1990.02a
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    • pp.185-189
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    • 1990
  • 고강도 레이저 장에서 마그네슘 원자의 다광자 이온화에 미치는 레이저 parameter의 영향을 Time-of-Flight spectrometer를 사용하여 분광학적 방법으로 연구하였다. 진공 챔버 속에서 파장 532nm와 1064nm인 레이저 펄스를 강도 1010-13W/'$ extrm{cm}^2$ 범위내에서 변화시키며 마그네슘 원자와 반응시켜서 Mg+ 및 Mg2+ 이온을 생성시켰으며 레이저의 파장, 강도 및 편광에 따른 광전자 스펙트럼을 구하였다. 또한, 전자 두 개를 방출하고 생성된 Mg2+ 이온의 발생 기구에 대하여 논하였다.

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Numerical Analysis of High-Order Harmonic Generation in Alkalic Metal Ions (알칼리 금속 이온에서의 고차고조파발생에 대한 수치해석)

  • 김규욱;김용평
    • Korean Journal of Optics and Photonics
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    • v.6 no.1
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    • pp.39-44
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    • 1995
  • 3차원 .delta.-potential을 가진 원자 모델을 이용하여 Nd:YAG(1064nm), Ti:sapphire(806nm), 색소(616nm), XeCl(308nm) 레이저를 기본파로 하고, 1차 이온화된 K/sup +/, Na/sup +/, Li/sup +/ 등의 알칼리 금속 이온을 비선형 매질로 할 때 고차고조파 분포를 수치적으로 해석하였다. 계산 결과 고차고조파 발생에서 특징적으로 나타나는 plateau는 비선형 매질의 이온화 에너지가 클수록, 기본파의 파장이 길수록 높은 차수에서 폭넓게 나타나고, 그 강도는 감소한다.

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Change in the Quality Characteristics of Acanthopanax and Cedrela Shoot by Salting Conditions (염장조건에 따른 오가피 및 참죽 순의 품질특성 변화)

  • Kim, Sun-Hwa;Jang, Se-Young;Jeong, Yong-Jin
    • Food Science and Preservation
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    • v.19 no.4
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    • pp.501-509
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    • 2012
  • The quality characteristics of Acanthopanax and Cedrela shoots during their preservation were investigated according to the salting conditions to improve the use of the shoots. The results were as follows: The pH of added ionization mineral during the storage did not change. The salinity of the salt-stored Acanthopanax and Cedrela tended to insignificantly change as their storage temperature changed and increase during the addition of the ionization mineral. In terms of the color values, the b value of the added non-ionization mineral tended to increase and that of the added ionization mineral tended to gradually decrease. The texture of Acanthopanax and Cedrela shoots to which an ionization mineral was added tended to decrease gradually during their storage, and was highest when 50 ppm of the ionization mineral was added. The total chlorophyll contents tended to decrease during the salt storage, did not change significantly with the change in the added ionization mineral, and decreased at the storage temperature of $10^{\circ}C$. Therefore, it can be concluded that quality of Acanthopanax and Cedrela shoots can be maintained when they are stored in ionization mineral addition.

Effect of Ionic Liquid on Increased Surface Area Crystallization Process for Vancomycin (표면적이 증가된 반코마이신 결정화 공정에서 이온성 액체의 영향)

  • Kim, Sung-Jae;Kim, Jin-Hyun
    • Microbiology and Biotechnology Letters
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    • v.42 no.3
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    • pp.297-301
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    • 2014
  • We examined the effect of ionic liquid on the crystallization efficiency of vancomycin in an increased surface area crystallization with silica gel. The crystallization efficiency was improved by the addition of ionic liquid, [BMIm][$BF_4$]. The addition of ionic liquid (20%, v/v) on the increased surface area crystallization with silica gel dramatically reduced the crystallization time by 6 folds (4 h), compared with the results of the case where the surface area-increasing material and ionic liquid had not been added. In addition, the crystal size of vancomycin was decreased and the crystal quality of vancomycin was improved by increasing the addition of ionic liquid.

Soil Ionization Phenomena around a Hemispherical Electrode Stressed by Impulse Voltages (임펄스전압에 의한 반구형 전극계에서 토양의 이온화 현상)

  • Heo, Dae-min;Kim, Hoe-gu;Lee, Bok-hee
    • KEPCO Journal on Electric Power and Energy
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    • v.2 no.4
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    • pp.601-608
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    • 2016
  • The electrical characteristics of the soil where a ground electrode is buried vary with regions, seasons and environmental factors. Electrical discharge in the vicinity of the ground electrode will occur differently and significantly affect the performance of the grounding system. It is necessary to analyze discharge and ionization characteristics of soils when the grounding system is designed. The aims of this investigation are to understand correlation between the soil ionization and the transient ground impedance. This paper presents the experimental results on the soil ionization parameters and the transient ground resistance due to the soil ionization around a hemispherical ground electrode stressed by lightning impulse voltages.

Potential Reduction and Energy Dispersion Due to Ionization Around the Submerged Ground Rod (수중에 잠긴 접지전극 주변에서의 이온화에 의한 전위저감 및 에너지방출)

  • Choi, Jong-Hyuk;Ahn, Sang-Duk;Yang, Soon-Man;Lee, Bok-Hee
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.23 no.1
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    • pp.92-99
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    • 2009
  • Deeply-driven ground rod in the rainy season may contact with rainwater and ground water. When surge voltages are applied to the submerged ground rods, the ionization around the ground rods are occurred. Ionization in soil and/or water is affected in dynamic performance of ground rod systems. This work aims at studying the transient performance of ground rod system under impulse voltage using scale model in an electrolytic tank. The potential reduction and energy dispersion caused by ionization were treasured and quantitatively analyzed using the Matlab Program. As a result, the peak voltage at the terminal of ground rod was varied with water resistivity and charging voltage of Marx generator. The potential at the terminal of the ground rod was approximately reduced to a half of the applied voltage just below breakdown voltage. Also the energy more than half of the applied energy was dispersed through the ground rod due to ionization just below breakdown voltage.

A Study of Multi-channel AFS for Marine Traffic Facilities (해양교통시설물용 다채널 AFS에 관한 연구)

  • Kim, Ji-Yoon;Lee, Ji-Young;Oh, Jin-Seok
    • Journal of Advanced Marine Engineering and Technology
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    • v.39 no.1
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    • pp.75-80
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    • 2015
  • After some period of time, the marine traffic facilities find problems caused by shellfish adhered to inside and inlet of the water column. Therefore, single-channel AFS(Anti-Fouling System) has been applied in order to minimize the deposition of shellfish. However, imbalance phenomenon of ionization of copper electrodes that are used for single-channel AFS appeared. This problem resulted in frequent replacement of anode. In this paper, multi-channel current control system has been developed, as well as the related hardware has been designed and fabricated. Further, experimental study has been undertaken to compare the application of single and multi- channel AFS. Through the sea experiments, it was possible to confirm that the copper electrode used for multi-channel AFS is uniformly ionized.

LC/ESI/MS 와 기능성 화장품 관련 분석에의 응용

  • 이명희
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.25 no.3
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    • pp.23-46
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    • 1999
  • LC/MS는 HPLC의 분리능과 질량분석기의 화합물의 확인 능력을 결합시킨 기기이다. 여기서 사용되는 이온화 방법은 GCJMS에서 사용되어지는 전자이온화법(electron ionization, EI)이나, 화학이온화법(chemical ionization, CI)은 부적당하기 때문에 최근 개발되어진 연성 이온화법의 대표적인 고속원자폭격식(Fast atom bombardment, FAB)이나 전기분무이온화식 (electrospray ionization, ESI) 등이 사용되고 있다. 이중 전기분무이온화법은 고속원자폭격법에서 사용되는 매트릭스를 사용하지 않기 때문에 매트릭스 이온의 부재로 인한 낮은 바탕 신호, 오래 지속되면서 안정된 초기 이온 전류, 샘플링의 용이성, HPLC와의 더 좋은 호환성 등의 장점을 제공한다. 이러한 전기분무이온화 방법은 극성이 매우 크거나 휘발성이 낮은 물질로 보통의 EI나 CI 이온화 방법으로 분석이 어려운 물질들을 분석할 수 있다. 또한 열에 불안정하거나 분자의 분자량이 다른 단백질 등의 분석도 가능하다. 이러한 LC/ESI/MS 방법을 이용하여 열에 불안정하고 극성이면서 분자량이 커서 GC/MS 펄의 분석이 어려운 기능성 화장품 원료로 주목받고 있고 생체에 존재하는 지질 성분으로 알려진 레시틴과 세라마이드의 분석이 가능함을 소개하고 분리와 동시에 그 분자량과 구조에 대한 정보를 빠르게 얻을 수 있음을 소개하였다.

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