• 제목/요약/키워드: excimer formation

검색결과 53건 처리시간 0.027초

The Effect of Ethanol on the Physical Properties of Neuronal Membranes

  • Bae, Moon-Kyoung;Jeong, Dong-Keun;Park, No-Soo;Lee, Cheol-Ho;Cho, Bong-Hye;Jang, Hye-Ock;Yun, Il
    • Molecules and Cells
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    • 제19권3호
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    • pp.356-364
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    • 2005
  • Intramolecular excimer formation of 1,3-di(1-pyrenyl) propane(Py-3-Py) and fluorescence polarization of 1,6-diphenyl-1,3,5-hexatriene (DPH) were used to evaluate the effect of ethanol on the rate and range of lateral and rotational mobilities of bulk bilayer structures of synaptosomal plasma membrane vesicles (SPMVs) from the bovine cerebral cortex. Ethanol increased the excimer to monomer fluorescence intensity ratio (I'/I) of Py-3-Py in the SPMVs. Selective quenching of both DPH and Py-3-Py by trinitrophenyl groups was used to examine the range of transbilayer asymmetric rotational mobility and the rate and range of transbilayer asymmetric lateral mobility of SPMVs. Ethanol increased the rotational and lateral mobility of the outer monolayer more than of the inner one. Thus ethanol has a selective fluidizing effect within the transbilayer domains of the SPMVs. Radiationless energy transfer from the tryptophans of membrane proteins to Py-3-Py was used to examine both the effect of ethanol on annular lipid fluidity and protein distribution in the SPMVs. Ethanol increased annular lipid fluidity and also caused membrane proteins to cluster. These effects on neuronal membranes may be responsible for some, though not all, of the general anesthetic actions of ethanol.

n-Alkanols가 소의 대뇌피질로부터 분리한 Synaptosomal Plasma Membrane Vesicles의 측방확산운동 범위와 속도에 미치는 영향 (The Effect of n-Alkanols on the Lateral Diffusion of Synaptosomal Plasma Membrane Vesicles Isolated from Bovine Cerebral Cortex)

  • 정인교;강정숙;윤일
    • 대한약리학회지
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    • 제29권1호
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    • pp.157-163
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    • 1993
  • n-Alkanols의 분자적 약리작용기전 탐구에 기초자료를 제공하기 위하여 소의 신선한 대뇌피질로부터 분리한 synaptosomal plasma membrane vesicles (SPMV) 지질 이중층의 측방확산운동에 미치는 n-alkanols의 영향을 형광 probe법으로 검색하였다. n-Alkanols는 SPMV 지질 이중층의 측방확산운동 범위와 속도를 농도 의존적으로 증가시켰고 1-nonanol까지는 탄소수가 두개 증가될 때마다 그 효력은 약 10배 가량 증가되었으나 탄소수 10개인 1-decanol의 효력은 오히려 감소되는 경향을 나타내었다.

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산업용 고부하버너 연소에서의 $NO_x$ 형성 및 저감에 관한 연구(I)-레이저 유도 형광법(LIF)를 이용한 이중선회 확산화염의 NO 농도 분포 측정- (A Study on Nitric Oxide Formation & Reduction in Industrial Burner (I) -NO Concetration-Distribution in Double Swirling Diffusion Flame by LIF-)

  • 박경석;김경수
    • 에너지공학
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    • 제10권4호
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    • pp.379-386
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    • 2001
  • 본 연구는 산업용 고부하 버너연소에서의 NO$_{x}$ 저감에 관한 실험적 연구이다. 본 연구에서는 NO$_{x}$의 정량적 농도 분포 측정을 위하여 레이저 유동 형광법을 사용하였다. XeCL 엑시머 레이저를 사용하여 NO A-X (0, 0) 진동밴드를 226 nm로 여기하였다. 또한 P$_{21}$+Q$_1$(14.5)/R$_{12}$+Q$_2$(20.5)/P$_1$(23.5) 전이를 여기라인으로 하였으며 다른 간섭의 영향을 최소화 하였다. 본 실험에서 이중선회 확산화염에서의 NO 농도 분포를 측정하였으며, 이 스월버너에서의 화염의 후류에 있어서 NO 농도는 1차/2차 공기비가 증가할 때 감소함을 알수 있었다.

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Barbiturates가 소의 신선한 대뇌피질 Synaptosomal Plasma Membrane Vesicles로 부터 추출하여 제제한 Phosphatidylethanolamine 인공세포막의 유동성에 미치는 영향 (Effects of Barbiturates on the Fluidity of Phosphatidylethanolamine Model Membranes)

  • 윤일;김형일;황태호;김종렬;김인세;정용자;신영희;정현옥;강정숙
    • 대한약리학회지
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    • 제26권2호
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    • pp.209-217
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    • 1990
  • Barbiturates가 분자적 약리작용기전 탐구에 기초자료를 제공하기 위하여 소의 신선한 대뇌피질 synaptosomal plasma membrane vesicles로부터 분리제제한 phosphatidylethanolamine인공세포막(SPMVPE)의 유동성에 미치는 barbiturates의 영향을 형광 probe법으로 검색한 결과는 다음과 같다. 1. Pentobarbital, hexobarbital, amobarbital 및 phenobarbital이 기재한 순위로 SPMVPE내 Py-3-Py의 monomer 형광세기에 대한 excimer 형광세기의 비 (I'/I)를 감소시켰다. 2. Pentobarbital, hexobarbital, amobarbital 및 phenobarbital이 기재한 순위로 SPMVPE내 DPH의 polarization, anisotropy, limiting anisotropy, order parameter 및 rotational relaxation time을 증가시켰다. 3. 따라서 위에 제시한 barbiturates가 SPMVPE의 유동성을 유의성있게 감소시킨다는 것을 확인할 수가 있었다.

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평면 레이저 유도 형광법(PLIF)을 이용한 $CH_4/O_2N_2$ 예혼합화염의 NO 농도 분포 가시화에 관한 연구 (A Study on the Visualization of NO Concentration Distributions in $CH_4/O_2N_2$ Premixed Flames by PLIF)

  • 박경석;이세환
    • 한국분무공학회지
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    • 제6권3호
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    • pp.1-7
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    • 2001
  • In this study, quantitative measurement of nitric oxide concentration distributions visualization were investigated in the laminar $CH_4/O_2N_2$ nixed flame by Planar laser-induced fluorescence(PLIF). The NO A-X (0,0) vibrational band around 226nm was excited using a XeCl excimer-pumped dye laser. Selecting an appropriate NO transition minimizes interference from Rayleigh scattering and $O_2$ fluorescence. The measurements were taken in $CH_4/O_2N_2$ premixed flame with equivalence ratios varying from $1.0{\sim}1.6$, and a fixed flow rate of 3slpm. NO was found to produce primarily between an inner premixed and an outer nonpremixed flame front, and total NO concentration is raised when equivalence ratios increase. These results suggest that prompt NO is likely to contribute to MO formation in $CH_4/O_2N_2$ premixed flame. Furthermore, this trend was well matched with previous works.

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Fabrication of Schottky barrier Thin-Film-Transistor (SB-TFT) on glass substrate with metallic source/drain

  • 장현준;오준석;조원주
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2010년도 하계학술대회 논문집
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    • pp.343-343
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    • 2010
  • In this paper, Schottky barrier thin-film-transistors (SB-TFTs) with platinum silicide at source/drain region based on glass substrate were fabricated. Poly-silicon on glass substrates was crystallized by excimer laser annealing (ELA) method. The formation of pt-silicide at source/drain region is the most important process for SB-TFTs fabrication. We study the optimal condition of Pt-silicidation on glass substrate. Also, we propose this device as promising structure in the future.

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레이저 유도 형광법(LIF)을 이용한 버너 화염의 NO 농도측정에 관한 연구 (A Study on Measurement of NO Concentrations in Burner Flames by LIF)

  • 박경석;김성욱
    • 한국분무공학회지
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    • 제7권4호
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    • pp.42-49
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    • 2002
  • In this study, quantitative measurement of nitric oxide concentration distributions were investigated in the laminar CH4/O2/N2 premixed flame by laser-induced fluorescence (LIF). The NO A-X (0,0) vibrational band around 226nm was excited using a XeCl excimer-pumped dye laser. Selecting an appropriate NO transition minimizes interference from Rayleigh scattering and O2 fluorescence. The measurements were taken in CH4/O2/N2 premixed flame with equivalence ratios varying from $1.0{\sim}1.6$, and a fixed flowrate of 5slpm. NO was found to produce primarily between an inner premixed and an outer nonpremixed flame front, and total NO concentration is raised when equivalence ratios increase. These results suggest that prompt NO is likely to contribute to NO formation in CH4/O2/N2 premixed flame. Furthermore, this trend was well matched with previous works.

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스월형 GDI 엔진의 연료혼합특성 연구 (Aspects of Mixture Formation in a Swirl Type GDI Engine)

  • 김기성;박상규
    • Journal of Advanced Marine Engineering and Technology
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    • 제27권2호
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    • pp.260-271
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    • 2003
  • For the Purpose of understanding the mixing phenomena of a GDI(Gasoline Direct Injection) engine, the spray behaviors and fuel distributions were investigated in a single cylinder transparent GDI engine. The experimental engine is a swirl type GDI engine with a SCV(Swirl Control Valve). PLIF(Planar Laser Induced Fluorescence) system with KrF Excimer laser was used for the measurement of the fuel distributions. The effects of SCV opening angles and the injector specifications on the fuel distribution characteristics were investigated. As a result, it was found that the SCV opening angle had a great effect on the fuel distributions in the late stage of compression process by changing the flow fields in the combustion chamber.

Cemented Carbide기판의 레이저 표면 개질이 다이아몬드 박막의 접합력에 미치는 영향 (Effect of Laser Surface Modification of Cemented Carbide Substrates on the Adhesion of Diamond Films)

  • 이동구
    • 열처리공학회지
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    • 제13권3호
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    • pp.170-176
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    • 2000
  • A novel method for improving the adhesion of diamond films on cemented carbide tool inserts has been investigated. This method is based on the formation of a compositionally graded interface by developing a microrough surface structure using a pulsed laser process. Residual stresses of diamond films deposited on laser modified cemented carbides were measured as a function of substrate roughness using micro-Raman spectroscopy. The surface morphology and roughness of diamond films and cemented carbides were also investigated at different laser modification conditions. It was found that the increasing interface roughness reduced the average residual stress of diamond films, resulting in improved adhesion of diamond films on cemented carbides.

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Effect of Drug Substances on the Microviscosity of Lipid Bilayer of Liposomal Membrane

  • Han, Suk-Kyu;Kim, Jin-Suk;Lee, Yong-Soo;Kim, Min
    • Archives of Pharmacal Research
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    • 제13권2호
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    • pp.192-197
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    • 1990
  • The microviscosites of the lipid bilayers of liposomal membranes of phospholipids were measured by the intermolecular excimer, formation method employing pyrene as a fluorescence probe, and the effects of n-alkanols and other local anesthetics on the microviscosity were investigated. The results showed that the n-alkanols and the ohter local anesthetics effectively lowered the microviscosity of the lipid bilayer of the dipalmitoyl phosphatidycholine liposomal membrane in proportion to the concentration of the additives. Moreover, there was a fairly good correlation between the ocal anesthetic activities and the microviscosity-lowering activities of these drugs. This results suggests that the nerve blocking activity of local anesthetics might have some relation with their activity fluidizing the lipid bilayer of biomembrane.

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