• Title/Summary/Keyword: charge distribution

Search Result 707, Processing Time 0.053 seconds

A Numerical Study on the Triboelectrostatic Separation of PVC Materials From Mixed Plastics for Waste Plastic Recycling

  • Ha, Man-Yeong;Jeon, Chung-Hwan;Park, Doo-Seong;Park, Hae-Jin
    • Journal of Mechanical Science and Technology
    • /
    • v.17 no.10
    • /
    • pp.1485-1495
    • /
    • 2003
  • We investigate the triboelectrostatic separation of polyvinylchloride (PVC) from mixed plastics in the laboratory scale triboelectrostatic separation system. The flow and electric fields in the precipitator are obtained from the numerical solution of finite volume method. Using these flow and electric fields, we solved the particle motion equation considering the inertia, drag, gravity and electrostatic forces acted on the particles. The particle trajectories are obtained using a Lagrangian method as a function of different important variables such as Reynolds number, Stokes number, electrostatic force, electric charge and electric field distribution, inclined angle of plane electrodes, particle rebounding, particle charge decay rate after impact on the electrode surface, etc., in order to determine the optimal design conditions. The present predicted results for the cumulative yield represent well the experimental ones.

Feature of the Change of the Arsenic Ionic State and Prediction of Toxicity in Aqueous Environment depending on Temperature Condition (온도 조건에 따른 비소 이온의 수중 상태 변화 특성 및 독성 예측)

  • Won, Yu-Ra;Kim, Dong-Su
    • Journal of Korean Society on Water Environment
    • /
    • v.29 no.2
    • /
    • pp.176-183
    • /
    • 2013
  • The variation of the stable region of arsenic compounds in aqueous environment with temperature has been investigated by constructing the Pourbaix diagram of arsenic at different temperatures. The standard potential corresponding to the boundary between arsenic compounds with different charge valence was estimated to be decreased with temperature, which means the stability of arsenic compound with +5 charge valence increases. The distribution diagram of the most highly oxidized arsenic compound showed that arsenic acid is formed at higher pH and arsenate is generated at lower pH as temperature rises. The aquatic toxicity due to arsenic compounds was considered to be decreased with temperature in the neutral pH condition based on the LDT value defined in this study.

A study on Electrical Potential Characteristics of HDPE Mixed with EVA (HDPE/EVA혼합수지의 전기적 분포 특성에 관한 연구)

  • Jung, Eui-Hwan;Heo, Jun;Lee, Seung-Su;Lim, Kee-Joe;Lee, Hyung-Kyu
    • Proceedings of the KIEE Conference
    • /
    • 2009.07a
    • /
    • pp.1447_1448
    • /
    • 2009
  • In this paper, each specimen blended at weight proportions of 80% HDPE to 20% EVA, 70% HDPE to 30% EVA, 60% HDPE to 40% EVA, and 50% HDPE to 50% EVA was manufactured respectively. The insulation performances of the proposed insulator were compared with conventional XLPE, main insulating material of CV cable on the basis of the investigation results of DC insulation performances. From the space charge density, electric field and potential profiles with raising DC voltage and time variation in HE82, distortion of electric field distribution was improved. As EVA mixed into the bulks acts as nucleation in crystallization process of HDPE, the size of spherulites became decreased and finally formed continuous network structure. Ultimately it resulted from extinction of space charge in the interfacial region of spherulites.

  • PDF

Inflence of carbonization temperature on electrochemical performance of multi-walled carbon nanotube/poly(vinylidene fluoride) composite-derived carbons (탄소나노튜브/폴리비닐리덴 플루오라이드 복합체로부터 제조된 탄소의 탄화온도에 따른 전기화학적 특성)

  • Kim, Ji-Il;Park, Soo-Jin
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2011.05a
    • /
    • pp.214.2-214.2
    • /
    • 2011
  • In this work, porous carbon based electrodes are prepared by carbonization using poly(vinylidene fluoride) (PVDF)/carbon nanotube (CNT) composites to further increase the specific capacitance for supercapacitors. Electrode materials investigate the aspects of specific capacitance, pore size distribution and surface area: influence of carbonization temperatures of PVDF/CNT composites. The electrochemical properties are investigated by cyclic voltammetry, impedance spectra, and galvanostatic charge-discharge performance with in TEABF4 (tetraethylammonium tetrafluoroborate)/acetonitrile as non-aqueous electrolyte. From the results, the highest value of specific capacitance of ~101 Fg1 is obtained for the samples carbonized at 600C. Furthermore, pore size of samples control be low 7 nm through carbonization process. It is suggested that micropores significantly contribute to the specific capacitance, resulting from improved charge transfer.

  • PDF

LED Driving Circuit using Charge Pump for Voltage Distribution (전압 분배용 전하펌프를 사용한 LED 구동회로)

  • Yun, Jang-Hee;Yoo, Sung-Ho;Ryeom, Jeong-Duk
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
    • /
    • v.26 no.8
    • /
    • pp.1-7
    • /
    • 2012
  • In this paper, a new LED driving circuit which is able to control dimming of LED is proposed using charge pump. The proposed LED driving circuit steps down the input voltage to operate LED without DC-DC converter. The operation of this driving circuit is verified by P-Spice simulation, and the characteristics of the driving circuit is measured and evaluated in the experiments. As a result, the driving circuit efficiency of 88.5[%] is obtained when all LEDs are turned on by digital control method at the highest dimming level(255/255).

Experimental Study on Spray Structure of a High Pressure 6-Hole Injector by Mie Scattering Technique (미산란 기법에 의한 고압 6공 연료분사기의 분무형상에 대한 실험적 연구)

  • Kim, Seong-Soo
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.32 no.11
    • /
    • pp.878-883
    • /
    • 2008
  • The spray characteristics of a high pressure 6-hole injector were examined in a single cylinder optical direct injection spark ignition (DISI) engine. The effects of injection timing, in-cylinder charge motion, fuel injection pressure and coolant temperature were investigated using the 2-dimensional Mie scattering technique. It was confirmed that the in-cylinder charge motion played a major role in the fuel spray distribution during the induction stroke while the propagation of fuel spray was restrained during the compression stroke by the increasing pressure and the upward moving piston. In additions, it was confirmed that the liquid fuel droplets existing at the sprays edges were vaporized by the increase of the coolant temperature.

Development and Performance Test of In-situ Particle Monitoring System using Ion-counter in Vacuum Environments (진공 환경내 실시간 입자 모니터링 시스템의 개발 및 성능평가)

  • Ahn Kang-Ho;Kim Yong-Min;Kwon Yong-Taek
    • Journal of the Semiconductor & Display Technology
    • /
    • v.5 no.1 s.14
    • /
    • pp.45-49
    • /
    • 2006
  • In this paper, a new method that monitors the quantity of particles using ion-counter in vacuum environment is introduced. In-situ particle monitoring (ISPM) system is composed by Gerdien type ion-counter (house-made), DC power supply and electrometer. The ion-counter applied by positive voltage detects only positive charged particles. Therefore the particles to be detected should be in known charge state for further data analysis. ion-counter is installed at the exhaust line of process equipment where the pressure loss is structurally low. ISPM system performance has been verified with SMPS (Scanning Mobility Particle Sizer) system. The correlation coefficient is above 0.98 at the particle size range of 20300nm in diameter with identified charge distribution under 0.110.0 Torr.

  • PDF

On the Vibration Characteristics and Determination of Site Constants for Surface Blasting (노천굴발파의 진동특성과 입지상수 결정에 관한 연구)

  • 양형식;주재성
    • Explosives and Blasting
    • /
    • v.8 no.4
    • /
    • pp.23-29
    • /
    • 1990
  • Some surface blasting vibration was measured to determine site constants and vibration frequency was analyzed. The results are summarized as follows; 1) Design method to predict particle velocities was introduced using the logarithmic normal distribution characteristics of peak particle velocities. 2) Scaled distance diagram to determine limiting charge was presented. 3) Line fitness between particle velocity and scaled distance didn't depend on dominant component of vibration. Prevail fitness was in the order of transverese, peak, vertical and radial component. 4) Dominant component of particle velocity didn't related to drilling direction. Frequency was lowered as distance enlarged. Duration time of vibration was shortened as charge decreased.

  • PDF

Analysis of Anomalous Subthreshold Characteristics in Ligtly-Doped Asymmetric Double-Gate MOSFETs (Asymmetric Double-Gate MOSFET의 Subthreshold 특성 분석)

  • 이혜림;신형순
    • Journal of the Institute of Electronics Engineers of Korea SD
    • /
    • v.40 no.6
    • /
    • pp.379-383
    • /
    • 2003
  • The subthreshold characteristics of Double-Gate MOSFETs are analyzed for various Tsi. In the lightly-doped asymmetric device, it is found that the subthreshold current dramatically increases as the Tsi increases and this phenomenon is due to the linear distribution of potential in the channel region with low depletion-charge. Further, we derived an analytical equation which can explain this phenomenon and verified the accuracy of analytical equation by comparing with the result of device simulation.

Current Density Equations Representing the Transition between the Injection- and Bulk-limited Currents for Organic Semiconductors

  • Lee, Sang-Gun;Hattori, Reiji
    • Journal of Information Display
    • /
    • v.10 no.4
    • /
    • pp.143-148
    • /
    • 2009
  • The theoretical current density equations for organic semiconductors was derived according to the internal carrier emission equation based on the diffusion model at the Schottky barrier contact and the mobility equation based on the field dependence model, the so-called "Poole-Frenkel mobility model." The electric field becomes constant because of the absence of a space charge effect in the case of a higher injection barrier height and a lower sample thickness, but there is distribution in the electric field because of the space charge effect in the case of a lower injection barrier height and a higher sample thickness. The transition between the injection- and bulk-limited currents was presented according to the Schottky barrier height and the sample thickness change.