• 제목/요약/키워드: Capillary action

검색결과 71건 처리시간 0.025초

Capillary Force Lithographic Patterning of a Thermoplastic Polymer Layer for Control of Azimuthal Anchoring in Liquid Crystal Alignment

  • Kim, Hak-Rin;Shin, Min-Soo;Bae, Kwang-Soo;Kim, Jae-Hoon
    • Journal of Information Display
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    • 제9권1호
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    • pp.14-19
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    • 2008
  • We demonstrated the capillary force lithography (CFL) method for controlling the azimuthal anchoring energy of a liquid crystal (LC) alignment layer. When a thermoplastic polymer film is heated to over the glass transition temperature, the melted polymer is filled into the mold structure by the capillary action and the aspect ratio of the pattern is determined by the dewetting time of the CFL process. Here, the proposed method showed that the azimuthal anchoring energy of the LC alignment layer could be simply controlled by the surface relief patterns which were determined by the dewetting times during the CFL patterning.

A Capillary Electrochromatographic Microchip Packed with Self-Assembly Colloidal Carboxylic Silica Beads

  • Jeon, In-Sun;Kim, Shin-Seon;Park, Jong-Man
    • Bulletin of the Korean Chemical Society
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    • 제33권4호
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    • pp.1135-1140
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    • 2012
  • An electrochromatographic microchip with carboxyl-group-derivatized mono-disperse silica packing was prepared from the corresponding colloidal silica solution by utilizing capillary action and self-assembly behavior. The silica beads in water were primed by the capillary action toward the ends of cross-patterned microchannel on a cyclic olefinic copolymer (COC) substrate. Slow evaporation of water at the front of packing promoted the self-assembled packing of the beads. After thermally binding a cover plate on the chip substrate, reservoirs for sample solutions were fabricated at the ends of the microchannel. The packing at the entrances of the microchannel was silver coated to fix utilizing an electroless silver-plating technique to prevent the erosion of the packed structure caused by the sudden switching of a high voltage DC power source. The electrochromatographic behavior of the microchip was explored and compared to that of the microchip with bare silica packing in basic borate buffer. Electrophoretic migration of Rhodamine B was dominant in the microchip with the carboxyl-derivatized silica packing that resulted in a migration approximated twice as fast, while the reversible adsorption was dominant in the bare silica-packed microchip. Not only the faster migration rates of the negatively charged FITC-derivatives of amino acids but also the different migration due to the charge interaction at the packing surface were observed. The electrochromatographic characteristics were studied in detail and compared with those of the bare silica packed microchip in terms of the packing material, the separation potential, pH of the running buffer, and also the separation channel length.

조건적 불사화 흰쥐 뇌 모세혈관 내피세포주에서 Taurine 수송 특성 (Characterization of Taurine Transport in Conditionally Immortalized Rat Brain Capillary Endothelial Cell Lines)

  • 강영숙;이나영
    • Biomolecules & Therapeutics
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    • 제10권2호
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    • pp.99-103
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    • 2002
  • Taurine has a neuroprotective action from oxidative stress in neural cell. In the present study, we studied taurine transport under basal and stressed conditions in conditionally immortalized rat brain capillary endothelial cell line (TR-BBB13) in vitro. The uptake of[$^3{H}$]taurine in the TR-BBB13 was increased by time-dependently and dependent on both Na$^{+}$ and Cl/ sup -/. Furthermore, $\beta$-alanine strongly inhibited the uptake of [TEX>$^3{H}$]taurine in the TR-BBB13. To study the effcts of oxidative stress on taurine transport, we used diethyl maleate (DEM) and lipopolysccharide (LPS). Diethyl maleate (DEM, $300\Mu\textrm{M}$) significantly reduced uptake of [TEX>$^3{H}$]taurine by time-dependently until 8 hr exposure in TR-BBB 13. But, the [TEX>$^3{H}$]taurine uptake was not changed by lipopolysccharide (LPS, 10 ng/ml) in TR-BBB13.3.

증발 코팅법으로 증착된 광유와 실리콘 오일 윤활제의 마찰 저감 특성 (Friction Reduction Properties of Evaporation Coated Petroleum and Silicone Oil Lubricants)

  • 유신성;김대은
    • 한국정밀공학회지
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    • 제30권8호
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    • pp.864-869
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    • 2013
  • As the size of mechanical components decreases, capillary forces and surface tension become increasingly significant. A major problem in maintaining high reliability of these small components is that of large frictional forces due to capillary action and surface tension. Unlike the situation with macro-scale systems, liquid lubrication cannot be used to reduce friction of micro-scale components because of the excessive capillary and drag forces. In this work, the feasibility of using evaporation to coat a thin film of organic lubricant on a solid surface was investigated with the aim of reducing friction. Petroleum and silicone oils were used as lubricants to coat a silicon substrate. It was found that friction could be significantly reduced and, furthermore, that the effectiveness of this method was strongly dependent on the coating conditions.

p-Methoxycinnamic acid의 소염작용 (Anti-inflammatory action of p-methoxycinnamic acid)

  • 신국현;이은방;우원식
    • 약학회지
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    • 제14권3_4호
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    • pp.45-50
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    • 1970
  • Anti-infalmmatory action of p-methoxycinnamic acid (p-MCA) was investigated. p-MCA showed a significant decrease in carrageenin and acetic acid induced edema of the rat hind paw, and increased capillary permeability by anaphylaxis and chemical mediators of pontamine sky blue in the mouse peritoneal cavity. It, however, showed only weak inhibitory effect on cotton pellet-induced granuloma formation of the rat.

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Rehmanniae Radix에 의한 가토 동방결절 및 유두근의 활동전압의 변동 (Effects of Ethanol Extract of Rehmanniae Radix(RREE) on Resting and Action Potential of Rabbit Sinoatrial Node and Papillary Muscle)

  • 황보상;고상돈;신홍기;김기순
    • The Korean Journal of Physiology
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    • 제19권2호
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    • pp.127-137
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    • 1985
  • The present study was undertaken in order to investigate effect of ethanol extract of Rehmanniae radix(RREE) on electrophysiology of sinus node and papillary muscle. Rehmanniae radix is a herbal medicine which has been known to have diuretic, antipyretic, hemopoietic and cardiotonic effects. Action potentials were recorded by means of glass capillary microelectrode(technique) in rabbit sinoatrial nodal cells and papillary muscle cells which were superperfused with either tyrode solution or tyrode solutions containing different amount of RREE. The results obtained were as follows ; 1) In both central and peripheral nodal cells maximum diastolic potential (MDP) and amplitude of action potential (APA) were not affected by RREE. 2) Action potential duration as expressed $APD_{60}$(time to 60% repolarization) of central and peripheral pacemaker cells were significantly prolonged following perfusion with tyrode solution containing 0.1% RREE. 3) The rates of spontaneous firing from central pecemaker cell were decreased by RREE at concentration of 0.05% and 0. 1% while spontaneous rhythm of perinodal cell was decreased by 0.1% RREE. 4) The action potential duration of papillary muscle as expressed $APD_{60}$ were prolonged by 0.1% RREE.

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천초(川椒) 및 산초(山椒)의 효능(?能)에 관(關)한 실험적(實驗的) 연구(硏究) (?Experimental Study on the Effects of Zanthoxyli Fructus and Fagarae mandshuricae Fructus)

  • 오한균;원종훈;정규만
    • 대한한방소아과학회지
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    • 제4권1호
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    • pp.1-17
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    • 1990
  • ?In order to investigate effects of Zanthoxyli Fructus (Sample-A) and Fagarae mandshuricae Fructus (Sample-B), experimental study was performed through observation on isolated - ileum analgesic, hypothermal, anti-pyretic, anti-inflammatory, capillary permeability, blood flow rate, blood pressure and respiratory works. The results were as follows; 1. In spontaneous movement of mice isolated-ileum, both samples were noted to have strong inhibitory action after temporary contraction, and to show antagonism against acetylcholine chloride and barium chloride. 2. Both samples were showed to have antihistamin work on guinea pig isolated-ileum 3. In analgesic work by the acetic acid method, only Fagarae mandshuricae Fructus was proved to have significant analgesic effect in mice. 4. Both sample groups indicated anti-pyretic and anti-inflammatory effect. 5. Both samples were noted to have inhibitory effect against capillary permeability ?rise in mice. ?6. Both samples were noted to have dose-dependent falling effect on blood pressure in rabbits.

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모세관 작용에 의한 콘택트 렌즈의 운동 모델 (Model on the Capillary Action-Induced Dynamics of Contact Lens)

  • 김대수
    • 한국안광학회지
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    • 제6권2호
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    • pp.85-97
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    • 2001
  • 눈물 층을 사이에 두고 각막 위에 부착되어 있는 렌즈(하드렌즈)에는 모세관작용에 따른 장력이 렌즈가장자리에 균일하게 방사형으로 향하여 작용한다. 순목등에 의한 충격으로 평형상태의 렌즈가 평형 위치에서 벗어나게 되면 눈물층의 간격에 변화가 발생하고 이 변화에 의해 불균일 모세관작용에 기인하는 장력에 따라 렌즈에는 복원력이 발생하고 이 힘에 의해 렌즈는 감쇄운동(진동)을 하게 된다. 이러한 복원력을 계산하고 렌즈의 운동을 예측할 수 있는 미분방정식과 컴퓨터프로그램을 수립하였으며 이 컴퓨터 모델을 사용하여 렌즈의 구경, 베이스 커브, 눈물 층의 두께 등의 변수가 렌즈의 운동에 미치는 영향을 모사(模寫)하였다. 눈물층의 점성에 의한 마찰력이 관성력에 비해 크기 때문에 렌즈는 진동을 하지 않고 시간의 경과에 따라 일률적으로 변위가 감소하는 운동양상을 나타내고 있으며 렌즈의 구경이 증가할수록, 눈물층의 두께가 얇아질수록 복원력이 증가하며 따라서 렌즈가 원위치로 되돌아오는데 걸리는 시간이 짧아지고 있다. 그러나 렌즈의 베이스커브는 그 값이 특정 값을 가질 때 원위치 도달 시간이 최소가 된다. 렌즈의 공진진동수는 눈물층의 두께가 증가할수록 렌즈구경이 감소할수록 낮아지고 있으며 베이스커브가 특정 값을 가질 때 공진진동수 역시 최대가 된다. 실제로 콘택트렌즈를 착용한 상태에서 렌즈의 공진진동수와 동일한 진동수의 외부 충격이 렌즈에 가해지는 경우 급격한 렌즈의 상하 또는 좌우 진동이 예상되며 따라서 렌즈가 탈착 된다든지 또는 렌즈의 형상변형으로 인해 각막에 통증이 발생할 수도 있을 것이다. 고함수(高含水) 소프트렌즈와 강은 diaphragm 그 자체는 탄성이 거의 없다. 그러나 함수 소프트렌즈가 각막 상에 눈물 층을 사이에 두고 부착되어 있는 경우에는 눈물의 표면 장력에 의해 탄성이 유기(誘起)될 수 있으므로 진동의 영향이 있을 것으로 본다.

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Anti-arthritic Effect of Glucosamine and Oriental Herbal Composition

  • ;;;;김영권
    • 대한의생명과학회지
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    • 제14권2호
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    • pp.97-103
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    • 2008
  • This study was conducted to investigate the effect of an anti-inflammatory and analgesic action of the glucosamine HCl (Glucosamine) and SH-1 (Glucosamine + Oriental herbal composition combined group). Male sprague-Dawley rats $(200{\sim}250g)$ and ICR mice $(20{\sim}30g)$ were randomized and these experimental groups were divided into 4 groups. Two control group were given as negative control (saline) and positive control (Ibuprofen, 100 mg/kg) and two groups given as oral administration of Glucosamine (320 m/kg) and SH-1. Carrageenan induced paw edema test, hot plate method, croton oil induced granuloma, capillary permeability test and acetic acid writhing syndrome were also shown to be comparable in the SH-1 group to anti-inflammatory drug group such as positive control group (Ibuprofen). Although further studies should be performed to confirm the effects of SH-1, present results suggest that the combined administration of SH-1 have potential action in anti-inflammatory and analgesic action. It could be applicable for the improvement of arthritic symptoms as a new diet-supplement.

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Dopamine이 토끼 유두근의 수축력과 활동전압에 미치는 영향 (Effects of Dopamine on the Contractility and Action Potential of the Rabbit Papillary Muscle)

  • 허인회;박종완
    • 약학회지
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    • 제32권6호
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    • pp.402-414
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    • 1988
  • In order to clarify the receptor types and mechanisms underlying the positive inotropic effect of dopamine on the mammalian ventricular myocardium, the action potential, its first derivatives and isometric contraction of the rabbit papillary muscle were recorded using a force transducer and glass capillary microelectrodes filled with 3M KCl. The results were as follows; (1) In normal Tyrode solution, the contractile force was increased and duration of action potential was shortened with increments of dopamine concentration ($10^{-6}-10^{-4}M$). (2) The dose-response curve was markedly shifted to the right by pretreatment with reserpine (5mg/kg i.p., 24hrs prior to the experiment). (3) In 19mM $K^+-Tyrode$ solution, the duration of action potential, maximum rate of rise (V_{max}) of action potential and overshoot were significantly increased with increments of dopamine concentration ($10^{-6}-10^{-4}M$). (4) The inotropic effect of dopamine on the rabbit papillary muscle pretreated with reserpine was antagonized by atenolol ($10^{-6}M$), but not by phentolamine ($3{\times}10^{-6}M$). (5) In rabbit papillary muscle partially depolarized by 19mM $K^+-Tyrode$ solution, slow electrical response (calcium mediated action potential) as well as contraction were restored by dopamine ($10^{-4}M$); this restoration was blocked by calcium antagonists ($3{\times}10^{-5}M$ $LaCl_3{\cdot}6H_2O$, $3{\times}10^{-6}M$ diltiazem) or ${\beta}-adrenoceptor$ antagonist ($3{\times}10^{-6}M$ atenolol), but not affected by ${\alpha}-adrenoceptor$ antagonist ($10^{-5}M$ phentolamine, $3{\times}10^{-6}M$ yohimbine) or vascular dopaminergic receptor antagonist ($10^{-5}M$ haloperidol). The above results may be interpreted as that the positive inotropic effect of dopamine through both direct and indirect action are caused by increase in slow inward current ($Ca^{2+}$ influx into themyocardial cell), and the direct action is mainly due to the stimulation of ${\beta}-adrenoceptors$ in the rabbit papillary muscle.

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