• 제목/요약/키워드: over-potential

검색결과 3,670건 처리시간 0.032초

Electrogravimetric and Electrochemical Ac Response of Polypyrrole Films

  • Yang, Haesik;Lee, Hochun;Kwak, Juhyoun
    • 분석과학
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    • 제8권4호
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    • pp.663-668
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    • 1995
  • Ion transport of a polypyrrole/chloride (PPy/Cl) film and a polypyrrole/poly(styenesulfonate) (PPy/PSS) film as a function of applied dc potential was investigated by employing electrogravimetric impedance technique and electrochemical impedance technique. The cation and anion contribution to the whole charge capacitance and the diffusion coefficients of cation and anion in a PPy/PSS film were calculated by fitting the electrogravimetric impedance data with proposed model circuit. The diffusion coefficients of $Na^+$ in a 1 M $NaClO_4$ solution are over 1 order of magnitude larger than those of $ClO{_4}^-$, and $ClO{_4}^-$ contribution to charge compensation decreases as dc potential lowers. The charge compensation of a PPy/Cl film ir a 1 M CsCl solution is carried out largely by $Cl^-$ at 0.2 V vs. Ag/AgCl and by $Cs^+$ as well as $Cl^-$ at -0.4 V.

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비 마약성 진통제 DA-5018의 신체의존성 (Physical Dependence on DA-5018, a Non-narcotic Analgesic Agent)

  • 강경구;김동환;백남기;김원배;양중익
    • Biomolecules & Therapeutics
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    • 제4권3호
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    • pp.232-238
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    • 1996
  • The physical dependence potency of DA-5018, a non-narcotic analgesic agent, was tested in mice dosed with 0.5 and 4 mg/kg/day for 2 months and daily increasing doses of 1, 2, 4, 6, 8 and 10 mg/kg over 10 days. Physical dependence was assessed taking natural withdrawal induced morphine-type abstinence (jumping, falling, biting or backward locomotion, rearing etc.) as well as barbiturates-type abstinence (body weight reduction, convulsion, ataxia etc.) into consideration. The results were compared with those after the same daily increasing doses of morphine. DA-5018 did not show evidence of physical dependence liability or abuse potential as measured by morphine-type or barbiturate-type abstinence signs following daily increasing or 2-month repeated administration. On the other hand, daily increasing doses of morphine produced physical dependence and the dependent state disappeared about 6 hours after the start of withdrawal signs. In the single dose suppression test, a single dose of morphine completely suppressed natural withdrawal signs that appeared in morphine-dependent animals. Therefore, these results indicate that DA-5018 does not have abuse potential and physical dependence liability.

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Development of an Equipment for Monitoring Current and Voltage on a Power Transmission Line

  • K. Kuwanami;E.Jishiuama;T Matsuda;I.Oota;H.Kuribayashi;N. Ueda;Ha, S.yata
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2000년도 ITC-CSCC -1
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    • pp.233-236
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    • 2000
  • A portable equipment that measures a current and voltage waveform of power transmission lines is pro-posed. In the equipment, the current and voltage, respectively, are detected by a loop coil and a capacitor clamped around the power lines. The detected data is transmitted by an FM wave to the receiver on the ground station. Since the receiver is isolated from the power lines, we do not require high potential insulators for the measurement of current and voltage. The proposed equipment is therefore, small-sized, light, and low in the cost of production. Experimental results presented here show that the equipment can monitor the current flowing in single wire over a ground plane and the potential of the wire.

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근위축성 측삭 경화증에서의 Statistical Motor Unit Number Estimate 재연성: Size-and Number-Weighted Modifications간의 비교 (Reproducibility of Statistical Motor Unit Number Estimate in Amyotrophic Lateral Sclerosis: Comparisons between Size-and Number-Weighted Modifications)

  • 권오현;이광우
    • Annals of Clinical Neurophysiology
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    • 제5권1호
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    • pp.27-33
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    • 2003
  • Background: Motor unit number estimation (MUNE) can directly assess motor neuron populations in muscle and quantify the degree of physiologic and/or pathologic motor neuron degeneration. A high degree of reproducibility and reliability is required from a good quantitative tool. MUNE, in various ways, is being increasingly applied clinically and statistical MUNE has several advantages over alternative techniques. Nevertheless, the optimal method of applying statistical MUNE to improve reproducibility has not been established. Methods: We performed statistical MUNE by selecting the most compensated compound muscle action potential (CMAP) area as a test area and modified the results obtained by weighted mean surface-recorded motor unit potential (SMUP). Results: MUNE measures in amyotrophic lateral sclerosis (ALS) patients showed better reproducibility with sizeweighted modification. Conclusions: We suggest size-weighted MUNE testing of "neurogenically compensated"CMAP areas present an optimal method for statistical MUNE in ALS patients.

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염색슬러지 연소재를 이용한 보도블록의 제작과 물성평가 (Manufacture and Characterization of Interlocking Block Using Incineration Ash of Dyeing Wastewater Treatment Sludge)

  • 권기홍;임우성
    • 한국환경보건학회지
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    • 제30권2호
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    • pp.167-172
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    • 2004
  • In this study, we carried out the research for the recycling potential of the dyeing wastewater treatment sludges as construction materials. The incineration ash of sludges were solidified as interlocking block in condition of sludge/cement ratio 2.5%, 5.0% and 10%, respectively. Those interlocking blocks were cured for 3days, 7days and 28days in ambient air condition, respectively. The results of this research were summarized as follows: The dyeing wastewater treatment sludges was below the Korea Leaching Limit. After incineration, the ash was manufactured as interlocking block. Bendable strength over 50kg$_{f}$/$\textrm{cm}^2$ suitable for interlocking block was obtained only when the sample was cured for 7days at sludge/cement ratio 2.5% and 5.0%. Hygroscopic ratio of interlocking block was above the Korea Industry Standard. We think that recycling of the incineration ash from dyeing wastewater treatment sludges to interlocking block will have high potential possibility.y.

실리콘 돌기의 응착마찰 분자동력학 시뮬레이션 (Molecular Dynamics Simulation of Adhesive Friction of Silicon Asperity)

  • 박승호;조성산
    • 대한기계학회논문집A
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    • 제28권5호
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    • pp.547-553
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    • 2004
  • A hemispherical asperity moving over a flat plane is simulated based on classical molecular dynamics. The asperity and the plane consist of silicon atoms whose interactions are governed by the Tersoff three-body potential. The gap between the asperity and the plane is maintained to produce attractive normal force in order to investigate the adhesive friction and wear. The simulation focuses on the influence of crystallographic orientation of the contacting surfaces and the moving direction. It is demonstrated that the adhesive friction and wear are lower when crystallographic orientations of the contacting surfaces are different, and also depend on the moving direction relative to the crystal1ographic orientation.

축대칭 부표의 규칙파중 운동특성에 대한 연구 (A Stuty on the Dynamic Response of an Axisymmetric Buoy in Regular Waves)

  • 홍기용;김효철;최항순
    • 대한조선학회지
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    • 제23권3호
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    • pp.1-9
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    • 1986
  • Herein the dynamic response of an axisymmetric buoy to regular wave is studied within linear potential theory. The buoy has a particular geometry so that it should experience minimum wave-exiting force on the vertical direction at a precribed wave number in water of finite depth. Invoking the Green's theorem a velocity potential is generated by distributing pulsating sources and doublets on the immersed surface of the buoy at its mean position. Hydrodynamic forces and moments are obtained approximately by summation of the products of linear pressure and directional mesh area over the immersed surface. Model tests are carried out to measure the wave-exciting forces, hydrodynamic forces and motion responses. The experimental results in general agree fairly well with the numerical ones. From the analytical and experimental works it is found that the pitching motion and its coupling effect affect significantly the motion characteristics of the freely-floating axisymmetric buoy in regular waves.

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전위장을 이용한 로봇 경로계획의 구조적 Local minimum을 극복하는 경로계획 방법 (A trajectory plannings avoiding structural local minimum problem in robot path planning using potential field)

  • 남헌성;이지홍;류준
    • 전자공학회논문지B
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    • 제33B권9호
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    • pp.13-23
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    • 1996
  • When artificial potential field approach is used to avoid obstacle, the problem can be occurred in case that manipulator selects the path which across over an obstacle among paths. In thiscase manipulator can't reach the desired goal form obstacle. This problem is a case of structual local minimum. so this paper proposes the method to solve structual local minimum in this case. The method is that the manipulator goes via temporary goal. This paper proposes that visual region concept to select the temporary goal. The temporary goal is selected on the border of the visual region. To prove its effectiveness, two simulation examples are done by two link manipulator in two dimension and by three link manipulator in three dimension.

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A Study on the Effectiveness of Smart Education Based on Learning Ability

  • Song, JeongBeom
    • 한국컴퓨터정보학회논문지
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    • 제21권9호
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    • pp.165-176
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    • 2016
  • This study developed the learning ability-based smart education program. The effectiveness of the developed materials was investigated using the quantitative-qualitative mixed method, and the process and results of the investigation are as follows. The quantitative investigation was conducted using the non-equivalent pretest-posttest design, in which the smart education method was applied to the experimental group, while the conventional education method was applied to the control group to analyze students' creative problem-solving potential, task concentration, and the variables required for the learning activity. The results showed significantly higher performance in the experimental group over the control group. Regarding data collection in the qualitative investigation, an analysis of the class from the instructor and class consultation logs from the class analyst were collected; the comments on the experience of each class period were collected from students. The results of the analysis of the data suggest that the perception of smart education improved for the instructor, class analyst, and learners as the course progressed.

Voltammetric Determination of Bisphenol A Using a Carbon Paste Electrode Based on the Enhancement Effect of Cetyltrimethylammonium Bromide (CTAB)

  • Huang, Wensheng
    • Bulletin of the Korean Chemical Society
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    • 제26권10호
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    • pp.1560-1564
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    • 2005
  • The influence of cetyltrimethylammonium bromide (CTAB) on the electrochemical behavior of bisphenol A at the carbon paste electrode (CPE) was investigated. CTAB, with a hydrophobic C-H chain, can adsorb at the CPE surface via hydrophobic interaction and then change the electrode/solution interface, and finally affects the electrochemical response of bisphenol A, confirming from the remarkable oxidation peak current enhancement. The electrode process of bisphenol A was examined, and then all the experimental parameters which affects the electrochemical response of bisphenol A, such as pH value of the supporting electrolyte, accumulation potential and time, potential scan rate and the concentration of CTAB, were examined. Finally, a sensitive and simple voltammetric method was developed for the determination of bisphenol A. Under the optimum conditions, the oxidation peak current of bisphenol A varied linearly with its concentration over the range from $2.5\;{\times}\;10^{-8}\;to\;1\;{\times}\;10^{-6}$ mol/L, and the detection limit was found to be $7.5\;{\times}\;10^{-9}$ mol/L. This method was successfully employed to determine bisphenol A in some waste plastic samples.