Abstracts of 2001 Annual Meeting the Institute of Electrostatics Japan
Presentation Number: 11aA-1
Title: Fundamental Characteristics of Positive Corona Discharge in Needle-to-Plane Electrode System
Authors and Affiliation: Seishu SHIMAMOTO*, Shuichi AKAMINE*, Seiji KANAZAWA*, Toshikazu OHKUBO*, Yukiharu NOMOTO*, Jerzy MIZERACZYK*@@*Department of Electrical and Electronic Engineering, Oita University, ** Institute of Fluid Flow Machinery, Polish Academy of Sciences
Abstract: In this study, corona current distributions at the plane electrode of dc positive needle-to-plane corona discharge were measured. Glow corona and streamer corona were produced separately by changing the needle electrodes. As a result, the current distribution of glow discharge was in good agreement with the well- known Warburg distribution. While, the current distribution of streamer corona discharge was sharper and narrower than that of glow discharge. For a fixed total current, the centerline current density of streamer discharge was high compared to that of glow discharge.
Presentation Number: 11aA-2
Title: Electric Field Strength and Surface Charge Density for Initiating Electrostatic Discharges between Charged Insulating Disks
Authors and Affiliation: Mitsuru MATSUI* and Koichi FUJIBAYASHI**@@*Zao ES Laboratory,**Department of Electrical and Electronic Engineering, Tokyo University of Agriculture and Technology
Abstract: Electrostatic discharges between charged insulating disks have been observed using spherical induction electrodes, and electric field strength between the disks has been calculated. Supposing the electrostatic discharge obeys Paschen criterion, the minimum surface charge density initiating the electrostatic discharge between the disks set at a spacing of 3 mm can be estimated as approximately 47 micro-coulombs per square meter that agrees with the experimental observation.
Presentation Number: 11aA-3
Title: Measurement of charge transferred by a partial discharge
Authors and Affiliation: Seiya@OGAWA@@Tokyo University of Agriculture and Technology
Abstract: A dielectric sheet is inserted between sphere and plane electrodes. The sheet is acrylic (0.5mm in thickness), and the gap between the sphere and the sheet is 50Êm. A ramp voltage (rise rate: 40V/sec) is applied, and the voltage is cut-off when a discharge pulse is detected. The sheet after the discharge is put into a faraday cage, and amount of the charge is measured. Black-red powder (tonor for electrophotography) is sprinkled over the surface of sheet, and distribution of the charge is made visible. The ring powder figures appear for both applications of positive and negative voltages. When positive voltage is applied to the sphere electrode, the discharge inception voltage is 2.3kV, and the charge measured is 694pC. For negative voltage application the discharge inception voltage is -2.2kV, and the charge measured is -158pC. Thus the charge transferred by the partial discharge for the positive application is larger (more than twice) than that for the negative application. The result measured will be useful, also for the study of the charging roller system of electrophotography.
Presentation Number: 11aA-4
Title: Electrostatic Discharge in Short Air Gap. U-Effect of surface roughness of electrode-
Authors and Affiliation: Noriaki MASUI, Shinichi TAMAMURA@@Faculty of Engineering, Science University of Tokyo
Abstract: This paper describes the dependence of dispersion of spark gap length on the surface roughness of spherical electrodes. Approaching speed between the electrodes is 0.4mm/s. Material of the electrode is brass and its diameter is 20mm. Electrode is roughened by abrading with polishing powder (mixture of iron and glass particles). Mean particle sizes of polishing powder are 595Êm (#30), 177Êm (#80) and 74Êm (#150). The electrode which surface is not roughened with polishing powder is also used. Positive 6kV is applied to the high voltage electrode and ceramic condenser of 100pF is connected to the electrode. The spark gap length increases with increasing surface roughness. Peak current is reduced with increasing the spark gap length. When the spark occurs at the same gap length, waveform of discharge current shows almost the same shape and peak current is almost the same value for the changes in the surface roughness of the electrode and the relative humidity in the discharge region. The spark gap length strongly depends on the surface roughness of negative electrode.
Presentation Number: 11aA-5
Title: On the Computing Programs of Electric FieldandSparkover Voltage in Standard Sphere Gaps
Authors and Affiliation: Yasuo@NISHIKORI@@Faculty of Engineering, Kogakuin University
Abstract: Although sparkover and corona starting voltages can be satisfactorily predetermined when empirical formulas or curves are available, a more general applicable method is required. An approach to such a method is through a modification of streamer theory, which, though possibly lacking in rigor, suffices in many cases for the accurate criterion of the breakdown voltages. The criterion by Pedersen in 1967 for air in standard sphere gaps was not entirely successful because of inadequate knowledge of the axial field distribution in gap spacing, but a deficiency is now remedied by the use of modification of the charge simulation method, taking account of the influences of both the shanks and the earthed plane.
Presentation Number: 11aA-6
Title: A Computer-Supported System for Electric Field Analysis by Using WWW Environment
Authors and Affiliation: Ryo NISHIMURA@@Tottori University
Abstract: In this paper we propose a remote electric field analysis system using the Internet environment. Recently, Internet becomes one of strong methods for information providing and sharing. Information sharing is important to improve technologies and engineering. Authors have been proposed a method to calculate electric field distributions around cylindrical electrodes by using charge simulation method assisted genetic algorithms. In this research, the electrical field calculation program is executed from the web page by using the WWW (World Wide Web) environment and CGI (Common Gate Interface) program. A client keys numerical conditions for the calculation into the input column on the web page. The CGI program receives the data and sends them to the electric field calculation program in the server computer. The client can obtain the numerical results, the positions of the fictitious charges and the contour points and the potential distribution around the electrodes, as a format of comma-delimited text file. We show an example of a method to share a technique on electrostatic analyses by using Internet.
Presentation Number: 11aA-7
Title: Studies on Electric Discharge in High-Intensity Acoustical Standing wave Field |Examination from a Current waveform|
Authors and Affiliation: Tatsutoshi SHINJO, Yuusuke NAGAI, Tetsuro OTSUKA and Tomoo NAKANE@@College of Industrial Technology, Nihon University
Abstract: It is published that the high sound energy affected to the discharging phenomena,such as influence the luminous part of the discharge. In this paper, the current waveform was measured by a digital oscilloscope in high intensity ultrasound field,the cycle and the peak value of the current wave produced a change by submitting sound pressure.
Presentation Number: 11aA-8
Title: Positive Corona Discharge at Disruption of Air Bubble under a DC Field
Authors and Affiliation: Yoshio Higashiyama, Hideyuki Kato, Toshiyuki Sugimoto and Yasushi Minamitani@@Faculty of engineering, Yamagata University
Abstract: Corona discharge from a water jet generated in burst of air bubble at water surface has been investigated under a negative electric field. Water droplets were ejected from the tip of the water jet. Positive corona discharge occurred intermittently from the tip of the water jet. The waveform of corona current was typical burst pulse. The influence of surface tension and conductivity of water on formation of water jet and on corona discharge was confirmed. The surface tension varies with temperature. Air bubble in water with lower emperature forms a water jetrapidly and disrupts relatively earlier than that with higher temperature. The magnitude of corona current from a water jet with higher conductivity is smaller than that with lower one.
Presentation Number: 11aA-9
Title: Influence of the ultrasonic wave exerted in water electric discharge
Authors and Affiliation: Yuusuke Nagai, Tatsutosi Shinjo, Tetsurou Otsuka, Tomoo Nakane@@College of Industrial Technology, Nihon University
Abstract: It has been published that a luminous part of a discharge in gaseous media is influenced by an ultrasound energy, but no data in liquid medium. In this paper, the discharge phenomena was experimented in a water with the ultrasound energyat 38 kHz, an applied voltage of the discharge was measured. As a result, the discharge phenomena in the liquid medium was influenced by the ultrasound energy.
Presentation Number: 11aB-1
Title: Comparison of OH behavior in pulsed corona and barrier discharge
Authors and Affiliation: Ryo ONO, Tetsuji ODA@@Department of Electrical Engineering, School of Engineering, the University of Tokyo
Abstract: Production and temporal decay of OH radical were compared between pulsed corona and pulsed dielectric barrier discharge (DBD). OH was measured by laser-induced fluorescence (LIF). The OH production process was different between the two discharges. Under DBD, charging current yielded OH, while charging current did not contribute to OH generation in corona discharge. The net current, given by discharge current minus charging current, yielded OH under corona discharge. As oxygen concentration raised, OH density increased. The rate of increase was nearly equal among positive and negative DBD, and positive corona. In negative corona, only a trace amount of OH was generated. The OH yield per discharge energy was determined. It was in the order of 10(13) cm(-3)/mJ. When trichloroethylene (TCE) was added to environment gas, OH density became considerably small in corona discharge. It was decreased to about 10% by addition of 300 ppm of TCE. On the other hand, OH density was almost constant in DBD when TCE was added up to 1000 ppm.
Presentation Number: 11aB-2
Title: Observation of NO Molecule in DC Streamer Coronas by Laser-Induced Fluorescence (II)
Authors and Affiliation: Yasuyuki SHUTO*, Naruaki SATO*, Seiji KANAZAWA*, Toshikazu OHKUBO*, Yukiharu NOMOTO*, Jerzy MIZERACZYK**@@* Department of Electrical and Electronic Engineering, Oita University,
** Institute of Fluid Flow Machinery, Polish Academy of Sciences
Abstract: Non-thermal plasma chemical processing for NOx removal has been studied in terms of both numerically by using plasma chemical models and experimentally. However, there is no sufficient plasma chemical process model which can describe the NOx removal process in a reactor. In this study, a laser induced fluorescence (LIF) method was employed for the observation of NO molecule dynamics during the NOx removal. In order to monitor the ground-state NO molecules, NO (X2®(v''=0)¨ A2°+(v'=0)) transition at 226nm was used. As a result, two-dimensional distributions of NO concentration in the reactor were determined as a function of operational time in NOx removal. The obtained results showed that the density of NO molecule decreased not only in the plasma region formed by the corona streamers but also in both the upstream and downstream regions of the reactor.
Presentation Number: 11aB-3
Title: Emission Spectroscopy of NO in Atmospheric Pressure Corona Discharge
Authors and Affiliation: Kazuo@Shimizu, Shusuke Saeki and Tetsuji Oda@@The University of Tokyo
Abstract: Emission spectrometry in the atmospheric pressure discharge was carried out to understand reaction mechanisms of active species, as the discharge plasma processing is significantly affected by the gas components. In this research, N2 second positive band and two band systems of NO such as NO-b band and NO-g band were investigated by using a digital controlled spectrometer and an ICCD camera. When the dielectric pellets were placed on the needle-plate type electrode, emissions from both N2 second positive band and NO-g band were declined along with the electrode axis. Observation by the time resolution of the emission spectrum resulted that N2 second positive band emission was extinguished within 200 nanoseconds, while that from NO-g band continued more than 1 microsecond. From these results, distribution of NO concentration in the corona discharge or barrier discharge was obtaine
Presentation Number: 11aB-4
Title: Measurement of atomic oxygen radical anion around atmospheric pressure by optogalvanic method
Authors and Affiliation: Yukimasa BABA, Masateru NISHIOKA, Masayoshi SADAKATA@@Faculty of Engineering, University of Tokyo
Abstract: Plasma discharge under atmospheric pressure has been applied in various fields, e.g. removal of air pollutant and plasma sterilization. However, the discharge mechanism has not been made clear because of the difficulty of measuring the intermediate-species in plasma at atmospheric pressure. In this study, atomic oxygen anion radical (O-) was measured by optogalvanic method in 2.6~102Pa to 2.0~103Pa and the density of negative ions was obtained in 3.7~102Pa. In this method, quenching of detached electrons cause large experimental error. Therefore the quenching process was estimated by calculation (including 42 element reactions). As the result, quantity of quenching electrons is below 0.1% and negative ions can be detected under the atmospheric pressure condition by this method.
Presentation Number: 11aB-5
Title: Decomposition of Dilute Trichloroethylene using Indirect Discharge Plasma
Authors and Affiliation: Kei YAMAJI, Tetsuji ODA and Tadashi TAKAHASHI@@The University of Tokyo
Abstract: Decomposition of dilute trichloroethylene (TCE) in air or O2/Ar gas was studied by using Indirect Non-Thermal Plasma. Indirect means to decompose by mixing with plasma processed clean air and TCE contaminated air. The reactor is a bolt type of 13.0mm inner diameter and is excited at 50Hz. TCE was decomposed by mixing with plasma processed O2/Ar gas. Although O radical generated by O3 ecomposition was assumed to react with TCE, O radical didn't affect TCE removal because O3 concentration didn't change after discharge. The relation of the humidiy and TCE decompostion was also experimentally studied. The decomposition efficiency of TCE was decreased by adding water where the humidity was roughly 90%.
Presentation Number: 11aB-6
Title: Decomposition of Trichloroethylene by using SPCP reactor
Authors and Affiliation: Nobuo HARADA, Tatsushi MATSUYAMA, Hideo YAMAMOTO@@Faculty of Engineering, Soka University
Abstract: We developed a new efficient apparatus for gas treatment in which a ceramic filter and SPCP (Surface corona discharge induced Plasma Chemical Process) were combined. SPCP is a method to activate gas-phase chemical reactions with surface discharge plasma. In this study, an applicability of the reactor to decomposition of trichloroethylene (TCE) was tested. The efficiency was examined against various conditions of initial concentration of TCE, with some kinds of carrier gases (air, nitrogen, and mixture of nitrogen and oxygen or water vapor and argon). TCE was removed with every condition effectively. When the carrier gas included oxygen source, the efficiency was higher than that with the nitrogen carrier. In particular, TCE was completely decomposed with discharge power of only 1W when the carrier gas was argon. The major parts of reaction products were measured and identified as inorganic compounds as hydrogen chloride, chlorine and carbon dioxide.
Presentation Number: 11aB-7
Title: Decomposition of Dilute Trichloroethylene using Non-Thermal Discharge Plasma with Catalysis
Authors and Affiliation: Kei YAMAJI, Yasuhisa TOKUDA, Tetsuji ODA and Tadashi TAKAHASHI@@The University of Tokyo
Abstract: Trichloroethylene (TCE) decomposition was investigated experimentally by using Non-Thermal Discharge Plasma with catalysis.
TCE removal with various catalyst, such as TiO2, V2O5/TiO2 (0.1wt%, 1.0wt%, 4.0wt%), MnO2, were tested. TCE removal rate was increased by synergistic effects of plasma excitation and catalytic activation, especially V2O5/TiO2 (1.0wt%) was the most efficiency. The effect of O radical generated from O3 decomposed by MnO2 on TCE removal was also experimentally studied. TCE decomposition efficiency was improved by using MnO2 in indirect plasma process.
Presentation Number: 11aB-8
Title: Characteristics of a Screen Type Ozonizer with Rod-to-Rod Electrodes
Authors and Affiliation: Yukiharu NOMOTO, Shuichi AKAMINE, Seiji KANAZAWA,Toshikazu OHKUBO@@Department of Electrical and Electronic Engineering, Oita University
Abstract: The silent discharge is mainly used for ozone generation in an ozonizer. Most practical ozonizer has a coaxial cylindrical electrode system with a gap of 1-2mm spacing and 1-2m length. In this study, instead of conventional coaxial cylindrical electrode system, a rod-to-rod electrode system is used. The tested ozonizer consists of nine units of the electrode system which are mounted in parallel in a box type reactor. The screen type uniform discharge can be obtained.in this ozonizer The effect of the number of electrode screen on ozone generation efficiency is investigated experimentally. As a result, the ozone generation efficiency is improved up to 15% higher by three electrode screens than that of one electrode screen.
Presentation Number: 11aB-9
Title: Dilute PFC Decomposition by the Non-Thermal Plasma
Authors and Affiliation: Tetsuji ODA and Mitsuko ITOH@@School of Engineering, the University of Tokyo
Abstract: For semiconductor process, various kind of PFCs (perfluorocarbon) are used now. It was found that PFCs also have strong green house effect and those emission into the air must be limited. Absolute concentration of PFC is very small and must be concentrated. A total gas pressure must be more than atmospheric pressure, otherwise that cannot release into air. The authors tried to decompose those PFCs by the non-thermal plasma of the barrier discharge and others. Considering the real condition and practical decomposition mechanism, CF4 in nitrogen or in synthesized air (80 % N2 and 20 % O2). Compared with the TCE decomposition, higher energy must be injected in order to decompose PFCs.
Presentation Number: PPaC-1
Title: DNA Sequencing Based on Molecular Surgery - Improvement of Yield -
Authors and Affiliation: Osamu Kurosawa1, 2, 3, Hiroyuki Kabata3 and Masao Washizu3@@1BRAIN (Seiken-Kiko), 2Advance Co., 3Kyoto University
Abstract: In DNA sequencing based on molecular surgery, 1) DNA is first stretched and immobilized onto a solid surface, 2) desired portion of the DNA is dissected and picked up, 3) an adapter sequence is ligated to the both ends of the dissected fragments, 4) the fragments are PCR amplified making use of the adapter sequence, and 5) the sequencing of the fragment is done with conventional biochemical methods. The processes 1) and 2) have been demonstrated in previous work by the authors, however, the number of obtained fragments appeared to be a factor of ten smaller than what is needed for the ligation process 3). There is adequate number of DNA molecules physically aligned in 1), but a large portion of them seemed to be damaged during the subsequent processes. In this paper, we show that the main mechanism for the loss is due to DNA damages a) by the fluorescence dyes when the labeled DNA is dried, and b) by the light irradiation for fluorescence excitation, which are needed for visualization during the molecular surgery. To avoid such damages, we adopted a new DNA labeling method, where fluorophores are introduced only to the molecular ends. This is done by the 3' to 5' digestion of DNA, followed by the incorporation of FITC-dUTP by a DNA polymerase. It yields the fluorescence bright enough so that the excitation can be reduced to 1/16 compared with what was used in the previous experiments. It is experimentally shown that adequate number of fragments can be obtained using the new method. Keywords: molecular surgery, DNA, dissection, sequencing, fluorescence labeling
Presentation Number: 11aC-2
Title: Development of Globule-coil State DNA Transition Technique
using Micro Needle Electrode
Authors and Affiliation: Jun KOMATSU, Shun-ichi MATSUURA, Tomonari SATO, Kazunori TAKASHIMA, Yukio MATSUZAWA, Shinji KATSURA, and Akira MIZUNO
@@Department of Ecological Engineering, Toyohashi University of Technology
Abstract: Fluorescent observation of a single DNA molecule may assist genetic analysis and gene mapping, etc, however these methods require an advanced micro manipulation technique which recovers a single DNA molecule from the sample solution, and fixes in a stretched form. Moreover, large DNA molecules are easily broken down by shear stress in the solution, therefore coiled DNA should be converted to globular DNA. This globular DNA can be reverted to original coil state by exchanging the buffer. Following operation was performed. 1) A globular DNA was attached to the tip of the micro needle electrode by gradient force. 2) The globule buffer was replaced with deionized water to transform the globular DNA to the random coil state DNA. As a result, the globular DNA has reverted to the random coil state DNA ,and the DNA was stretched and immobilized on a glass surface by sliding the glass on microscope stage or moving the needle electrode.
Presentation Number: 11aC-3
Title: Fluorescent Labeling of Individual DNA Polymerase and Visualization
Authors and Affiliation: Shun-ichi MATSUURA*, Yoshiyuki MIZUSHINA**, Hiroshi NAITO*, Jun KOMATSU*, Kengo SAKAGUCHI***, Shinji KATSURA* and Akira MIZUNO*@@*Department of Ecological Engineering, Toyohashi University of Technology, **Department of Nutritional Science, Kobe-Gakuin University, ***Department of Applied Biological Science, Science University of Tokyo
Abstract: Single DNA molecule observation permits the analysis of dynamics of protein such as polymerases although conventional assays elucidate averaged phenomena of proteins across a large number of DNA molecules. For example, single molecule observation based on a fluorescence microscopy provides a potential method for direct measurement of processivity and binding rate of protein. However, conventional methods of fluorescent labeling sometimes damage the enzymes seriously resulting in very low enzymatic activity, probably because of the binding of the dye to the functional site of the enzyme. We have developed the damage-free fluorescent labeling method for the microscopic observation. In our method, at first, DNA polymerase pre-bound on DNA molecule was chemically modified with amine-reactive fluorescent dye, Oregon Green 500. In next step, fluorescently labeled DNA polymerase was eluted from DNA with potassium chloride buffer. DNA-binding activity of the protein labeled in this way was not affected. We observed the fluorescent image of individual DNA polymerase b bound on straightened DNA molecule in the absence of dNTP and magnesium ion under a fluorescence microscope field. Our fluorescent labeling technique for DNA polymerase contributes to the observation of the dynamics of individual proteins on a single DNA molecule.
Presentation Number: 11aC-4
Title: Selective Detection of Bacteria by using Dielectrophoretic Impedance Measurement Method with Antigen-Antibody Reaction
Authors and Affiliation: Daisuke NOUTOMI, Junya SUEHIRO and Masanori HARA@@Graduate School of Information Science and Electrical Engineering, Kyushu University
Abstract: In our previous work, the authors proved how fast and easy was the Dielectrophoretic Impedance Measurement(DEPIM) method for detection technique of the biological cells supended in aqueous medium. So far, we've tested the DEPIM under the condition that only one strain of cells (E.coli) is suspended, whereas, in practical microorganism inspection, it is necessary to identify a particular strain of pathogenic bacteria from mixture of various bacteria. But the conventional DEPIM is not suitable for such a highly selective inspection because dielectric properties of bacteria are not so different between their species or strain that they are detected as an equivalent dielectric particle. In this paper, we propose two methods for selective bacteria detection using DEPIM combined with antigen-antibody reaction. In one method, antybody molecules are immobilized onto the microelectrode suraface, whereas, in the other method, agglutination of bacteria is employed to increase dielectrophoretic force. As a result, by using these metohds, we can leave target bacteria on the electrode surface. And furthermore, agglutinated bacteria can be electrically detected by DEPIM. It suggests that roposed methods can be more effective for selective detection in mixture of various bacteria.
Presentation Number: 11aC-5
Title: Development of amplification of unknown DNA fragment and
Authors and Affiliation: Michihiko NAKANO, Jun KOMATSU, Shunichi MATSUURA, Keita SAITO, Hiroyoshi INAMI, Hachiro YASUDA, Kazunori TAKASHIMA, Shinji KATSURA, and Akira MIZUNO@@Department of Ecological Engineering, Toyohashi University of Technology
Abstract: We have been developing a new method for rapid DNA sequencing. This method consists of fixation of single DNA molecule with stretched shapes, cutting with restriction enzyme in order from terminus of DNA, recovery of cut DNA fragment, and sequencing. Advantage of this strategy, in principle, is that only a single DNA molecule is enough and the recovered DNA fragments keep information on their order. To achieve this method, single molecule of unknown DNA fragment should be amplified using PCR (Polymerase Chain Reaction). So amplification of unknown DNA fragment using PCR and new method for Single-Molecule PCR have been developed. To amplify unknown DNA, known DNA (denoted as linker DNA) should be ligated to both ends of target DNA, then amplify by PCR using primer complementary to linker DNA. This study demonstrated that 100 molecules of unknown DNA fragment could be successfully amplified without removing the enzyme or linker DNA. By using water-in-oil (W/O) emulsion, single molecule DNA was successfully amplified as follows: At the beginning of the amplification, the 1st 13 thermal-cycles were carried out in W/O emulsion. Because individual droplet in water functions as micro-reactor, effective concentration of template DNA raised drastically. After that, the emulsion was broken by centrifuge, in order to use the substrate that had not been used in the 1st 13 cycles. Then further 25 cycles were carried out and products were analyzed by electrophoresi
Presentation Number: 11aC-6
Title: Effect of PEF on peroxidase activity and its application
Authors and Affiliation: Takayuki Oshima, Isamu Imaizumi, Yukio Saito and Masayuki Sato@@Faculty of Engineering, Gunma University
Abstract: Effects of pulsed electric field (PEF) on native and denatured peroxidase activities were studied in this study. When PEF was applied to denatured peroxidase by heat treatment (92.5,5min),peroxidase refolding was enhanced at appropriate conditions. Relative activity after spontaneous refolding was about 30%, and 40% of relative activity was observed after 11.7 kV/cm and 30sec of PEF treatment. However, more than 15 kV/cm of PEF treatment resulted in decreased activity. These results suggested that peroxidase refolding is affected by PEF treatment and it could control the peroxidase activity. We also studied the effect of PEF on immobilized peroxidase bound to cellulose particles covalently. The sensitivity of immobilized peroxidase to heat or PEF treatment was different from that of soluble peroxidase. After 65 and 2min of heat treatment, relative activity of peroxidase was 20%. However, 50% of relative activity was observed after 20 kV/cm and 30sec of PEF treatment. It was proven that PEF can enhanced the refolding of peroxidase.
Presentation Number: PPaC-V
Title: DEP Chromatography with Cross-Flow Injection
Authors and Affiliation: Hikari SANO, Hiroyuki KABATA, Osamu KUROSAWA and Masao WASHIZU@@Department of Mechanical EngineeringCKyoto University
Abstract: DEP chromatography device with a cross-flow injector is developed. The device has two fluid passages crossing each other, one for the separation and the other for the sample injection. An array of micro electrodes for the dielectro-phoretic (DEP) separation is located in the separation channel downstream of the intersection. First, the sample is fed through the injection channel to fill the intersection, and then a carrier fluid is pumped through the separation channel. This process enables the pulse-wise injection of the sample into the carrier stream, and the amount of the injected sample is determined by the volume of the intersection. The solute in the sample is then subjected to the non-uniform field created by the electrode array, and the more polarizable the solute is, the higher the chance of the DEP entrapment becomes, and as a result, more delayed from the stream. Thus, a separation depending on the dielectric properties of the solute become possible. Using the device, the separation of 0.1 mm and 1mm latex particle, and the separation of 6.6 kbp and 48.5kbp DNA are experimentally demonstrated under the field strength of 1.2MV/m at 1MHz. Keywords: dielectrophoresis, chromatography, m-TAS, cross-flow injection, separation, DNA
Presentation Number: 11pA-1
Title: PTFE Thin Film Fabrication by Using UV Laser Ablation
Authors and Affiliation: Tetsuji ODA and Murat O. KARADENIZ@@School of Engineering, the University of Tokyo
Abstract: A PTFE (polytetrafluoroethylene) thin film is fabricated by using KrF excimer UV laser ablation technology and characteristics of that manufactured film are identified by surface topology (AFM) and by chemical bonding analysis (XPS). Main parameters are silicon substrate temperature and gas conditions (vacuum or with argon gas). The short distance between the target and the substrate is preferable. The substrate temperature should be more than 90. XPS is very effective in investigating the bonding conditions between carbon and fluorine. RF-sputtered PTFE thin film shows miscellaneous carbon signals.
Presentation Number: 11pA-2
Title: Precise Measurement of Size and Charge for Electrostatic Agglomeration
Authors and Affiliation: Yoji NAKAJIMA* and Takashi SATO**@@*Division of Mat.Sci.& Eng., Hokkaido Univ. **Hokkaido Institute of Technology
Abstract: As is well known, oscillation of a charged particle in an alternating electric field reflects its size and charge, and therefore we can measure them by monitoring the oscillation. Usually, the Stokes drag formula for steady motion of a sphere is assumed to be usable also for oscillating motion because very precise measurement is not always expected, and moreover, no formulas for the drag of an oscillating sphere have been confirmed experimentally. One of such formulas is a special case of the so-called Basset solution for oscillating flow, in which the convective terms in the Navier-Stokes equations are completely ignored. Since the ignorance of the convective terms may pose serious hydrodynamic problems, the drag formula for a sphere in oscillating flow has not been well acknowledged. This time we experimentally verify the formula to show that it provides more accurate measurement of size and charge.
Presentation Number: 11pA-3
Title: Preparation of LSGM Films for Fuel Cells by Pulsed Laser Deposition
Authors and Affiliation: Takeshi ITO*, Kenji YAMADA*, Seiji KANAZAWA*, Toshikazu OHKUBO*, Yukiharu NOMOTO*, Tatsumi ISHIHARA**, Yusaku TAKITA**@@* Department of Electrical and Electronic Engineering, Oita University,
** Department of Applied Chemistry, Oita University
Abstract: Doped LaGaO3 oxide has shown superior oxide ion conductivity. It is a promising candidate for an electrolyte in solid oxide fuel cells. The films, with the composition La1-xSrxGa1-yMgyO3-(x+y)/2 was prepared by KrF pulsed laser deposition. The dynamics of the plasma plume during the film deposition was investigated. The estimated velocity of the plume head is in the range of (0.5-1.5)~104m/s depending on the operational pressure. The films deposited on the NiO substrate consisted of many particles and crystalline structure of LaGaO3 was obtained for post annealed films.
Presentation Number: 11pA-4
Title: Preparation of silver coated PE particles and measurement of their dielectric constants aiming at high performance ER suspensions
Authors and Affiliation: Yoshitomo TERUI, Yoji NAKAJIMA and Kunio SHINOHARA@@Division of Mat. Sci. and Eng., Hokkaido University
Abstract: High dielectric constant, low density, and spherically shaped particles are recommended for electrorheological (ER) suspensions. We focus our attention on composite particles (e.g., plastic particles covered with metal). This time we intend to prepare such particles with a machine named the hybridizer, in which high speed rotating blades hit particles to fixate fine silver powder on polyethylene (PE) particle surface. The dielectric constant of the composite particles in silicone oil was measured on the basis of Rayleigh's equation. In our measurements, a pronounced non-linear relationship between the capacitance change and the volume fraction of particles in the suspension was found to make the calculated dielectric constant unreliable. We extrapolated the measured values to zero concentration to obtain reasonable values for the dielectric constant of the composite particles. The highest dielectric constant of the composite particles thus obtained so far was 30 with a density of 1.14 g/ml.
Presentation Number: 11pA-5
Title: Microparticle capture using EDB and single particle Raman spectroscopy
Authors and Affiliation: Yutaka AOKI, Azuchi HARANO, Takayuki TAKARADA@@Faculty of Engineering, Gunma University
Abstract: The apparatus, which was combined with EDB(Electrodynamic Balance) and Raman spectroscopy, was made for analysis of a single particle. The single microparticle was captured between two cylinder type electrodes on which DC voltages were applied. AC H.V. was applied on outer cylindrical electrode for the particle stabilization. Particles containing Ca[CaCO3, CaSO4] in diameter less than 100Êm was used and Raman scattering from these particle was measured by argon ion laser. The excellent Raman spectra were obtained for identification of the chemical substance in calcium system
Presentation Number: 11pA-6
Title: Thermally Stimulated Current Spectra of Cryogenically Pulverized Polypropylene
Authors and Affiliation: Tatunori HASHIMOTO and Kazuo IKEZAKI@@Faculty of Science and Technology, Keio University
Abstract: Thermally stimulated current (TSC) spectra of polypropylene (PP) powders pulverized at low temperature were observed in the temperature range from room temperature to about 170 . The obtained TSC spectra of powder-formed PP were remarkably different from those of films made of the same PP resin. The powder-formed PP shows a main TSC band peaked at 105-112 depending on its particle size, though the film samples show two TSC bands peaked at 60 and 120 , respectively. Change in the higher order structure of PP induced by pulverization was found to be irreversible one, because annealing at about 150 of the pulverized PP did not bring about any changes in their TSC spectra. Observed results were discussed with the results of differential scanning calorimetry and wide angle X-ray diffraction
Presentation Number: 11pA-7
Title: Increase of Charge Decay on Low-density Polyethylene Film by Graft-copolymerization with Poly(Acrylic Acid)
Authors and Affiliation: Koichi MATSUMOTO and Yasuro HORI@@Department of Electrical and Computer Engineering, Nagoya Institute of Technology
Abstract: A surface of low density polyethylene (LDPE) film was modified by graft-copolymerization with poly(acrylic acid) in order to increase the surface charge decay without decreasing its high bulk electric resistance. The surface charge decay has been studied by measuring the two-dimensional distribution of charges, and its dependence on relative humidity was observed. The decay was very fast even at low humidity, and the spreading of charges along the surface was clearly observed. When the poly(acrylic acid) on the LDPE surface outside the certain square were removed, the surface charges have been observed not to migrate beyond that square and then the total charge did not decay even under 30% humidity. It was concluded that the charge migration along the surface was the major role in the charge decay on the LDPE film graft-copolymerized with poly(acrylic acid).
Presentation Number: 11pA-8
Title: Decay of charge on the surface of polymer films
Authors and Affiliation: Ryo Ono, Masaaki Nakazawa, Tetsuji Oda@@Department of Electrical Engineering, School of Engineering, the University of Tokyo
Abstract: Decay of charge on the surface of polymer films were measured by laser induced pressure method (LIPP). The film was charged by corona discharge in the atmosphere, then the charged surface of the film was shorten to the ground via a 50-Ohm resistor. The decay rate of the surface charge was almost equal among PTFE, FEP, and PP for several tens minutes after the short. After several hours, almost all of the charge had flowed into the ground. However, in PP, some charge remained inside the surface. The inner charge did not decrease with time at room temperature. It decreased as temperature increased.
Presentation Number: 11pA-9
Title: Increase of Surface Charge Decay on Polystyrene by Surface Modification with Sulfuric Acid
Authors and Affiliation: Katsuyoshi MORITA@@Department of Electrical and Computer Engineering, Nagoya Institute of Technology
Abstract: A surface of polystyrene (PS) film was modified with sulfuric acid. For this film, the increase of surface charge decay has been studied by measuring a series of two-dimensional distributions with time. The decay of charge density on the treated film was faster than that on untreated one, and the surface charges have decayed faster at higher humidity than at lower humidity. The spreading of charges along the surface was clearly observed. In order to make the charges not to migrate beyond the observed areas, the treated layer was squarely removed by the ditch dug on a treated PS film surface. On this sample, charges did not decay. Consequently it is concluded that the most part of charge decay on PS film treated with sulfuric acid occurred through the migration along the surface.
Presentation Number: 11pC-1
Title: Fundamental Characteristics of EHD Pump with Unit Electrode System
Authors and Affiliation: Kyoko Yatsuzuka, Shunsuke Tachibana and Kazutoshi Asano@@Faculty of Engineering, Yamagata University
Abstract: Electrohydrodynamic (EHD) pump could be a low cost and low power consuming pump, because its structure is simple without moving parts. We have investigated the fundamental characteristics of an ion drag type EHD pump with needle electrodes. In our previous reports, it is clarified that the EHD effect will be enhanced by taking advantage of fluid resistance. In this report module type electrode systems are utilized. The level of the silicone oil gradually rises up to over 400 mm when the DC high voltage is applied, and falls down quickly when the applied voltage is removed. The average value of rising velocity of the liquid level agrees with the evaluation from its mass velocity. When the modules of the electrode system are in series, only little advance is observed, or worse.
Presentation Number: 11pC-10
Title: Measurement of surface electric charge density of fibers of electret air filter
Authors and Affiliation: Shinpei Tsukamoto and Yuji Murata@@Science University of Tokyo,Faculty of Science & Technology
Abstract: Charging states of fibers of electret air filters was investigated using ultrafine toner particles for attaching to fibers. The obtained result showed that the fibers have an average of 1~10-5 C/m2 surface electric charge density. By using this method , it is thought that surface electric charge density of fibers can be used as one of the indices of performance of electret air filter.
Presentation Number: 11pC-2
Title: Separation of Water-in-Oil Emulsions by EHD Forces
Authors and Affiliation: Noriyasu YAMAMOTO, Shuichi AKAMINE, Seiji KANAZAWA, Toshikazu OHKUBO, Yukiharu NOMOTO@@Department of Electrical and Electronic Engineering, Oita University
Abstract: Electrohydrodynamics (EHD) is widely used to control the fluid motion. In the liquid, the EHD forces include electrophoresis force, ion drag force, dielectrophoresis force, etc. In this study, the separation of the water-in-oil emulsions by a dc electric field was carried out experimentally. The effect of the applied voltage, water concentration, and the electrode geometry on the separation of the emulsions was investigated. The separation rate was measured as a function of operational time. It was found that the separation was enhanced under a non-uniform field such as a needle-to-rods electrode system.
Presentation Number: 11pC-3
Title: Fundamental Characteristics of Induction Type Generators for Demonstration of Electrostatic Phenomena
Authors and Affiliation: Kyoko Yatsuzuka, Kyoichi Tamura and Kazutoshi Asano@@Faculty of Engineering, Yamagata University
Abstract: Electrostatic generators convert mechanical energy to electrical energy directly. They are simple and produce high voltage quickly, while the energy converted remains small. This report concerns about the induction-type electrostatic generator. Although this type generator were there very long time ago, the progress was slow until A. D. Moor made "dirod", one of the induction-type electrostatic generators, and used them for demonstration on the Electrostatics. We made handy sized dirods and examined them to see how high the voltage generated is. There are several parameters we have to pay particular attention. Any tiny discharge spoils its feature. The stability of voltage generated depends on the discharge, the polarity of voltage sometimes flips over. Several kinds of substances for the brushes, which are used to collect the conveyed charge from the moving rods, were examined. The conductive rubber shows reasonable results, because of its conductivity and elasticity
Presentation Number: 11pC-4
Title: Basic Research on Disk Type Corona Motors (Y)
Authors and Affiliation: Masayuki HATTORI*, Kouichi INOMATA*,Toshiyuki AOKI*,Yamato SEKI* and Kenkichi IZUMI**@@*Sendai National College of Technology, **Shishido Electrostatic, Ltd.
Abstract: In our previous reports, disk type corona motors using two different shapes of discharging electrodes as the stator have been made and tested. One is a thin copper foil type electrode, the other is a printed circuit board (pcb) type one, and it has been cleared that the latter is superior in various characteristics. Each disk of the rotor and the stator (discharging electrodes) has a structure which can utilize both sides of the disk for the purpose of extension to a multi-disk type corona motor. This time, we have made a CD (Compact Disk) type of rotor consisting of two CDs and have compared the torque characteristics with the former type of rotor (pcb rotor). It has been clarified that the CD type of rotor has the same torque but the smaller current compared with the pcb rotor, then can increase the efficiency. As an application of this motor, a new type of ozonic generation and circulation pump is proposed.
Presentation Number: 11pC-5
Title: Characteristics of Precipitation Efficiency and Gas Velocity for Electrostatic Precipitator of Special Structure
Authors and Affiliation: Ayumu IIJIMA@@Fukui University of Technology
Abstract: A new electrostatic precipitator structure is proposed and a preliminary precipitation efficiency study is presented. Conventional precipitators exhibit lower precipitation efficiency when gas flow is accordance with gas flow is increased in accordance with the Deutsch formula. The structure of the proposed precipitator is such that ion winds caused by corona discharges and gas currents collide against collecting electrodes. When the gas flow is increased in the proposed precipitator to process a greater volume of gas, the decrease in precipitation efficiency is small and the difference between the conventional and proposed techniques increases. Application of the proposed structure is expected to lead to a reduction in the size of precipitators.
Presentation Number: PPb|U
Title: Electrostatic Separation of Metallic Particles
Authors and Affiliation: Haruhisa FUJII*, Toshihiro IKAI** and Yasuto ISEKI***@@Advanced Technology R&D Center*, Industrial & Environmental Engineering Center** and Headquarter***, Mitsubishi Electric Corporation
Abstract: It is necessary to make the behavior of metallic particles clear in order to remove them in mixed plastics in the development of high-efficiency electrostatic separators for material-recycle use. In this paper, we described the analytical results of their behaviors in the electric field of a roll-type electrostatic separator.
Presentation Number: 11pC-7
Title: Motion and Estimated Charge of a Spherical Particle under Non-uniform Electric Field in Dielectric Liquid
Authors and Affiliation: Changrag CHOI, Kyoko YATSUZUKA and Kazutoshi ASANO@@Faculty of Science & Technology, Science University of Toyko
Faculty of Engineering, Yamagata University
Abstract: In order to seek a suitable electrode configuration removing impurities contained in liquefied plasitcs waste, a tilted plane electrode system is constructed and the particle motion was investigated under non-uniform electric field. The particle charged by induction moves either direction of the electrodes showing up-and-down motion. When the applied voltage is relatively low, the particle moves toward the narrow gap side and as the applied voltage is high enough, it moves toward the wider gap side. The particle was trapped at the middle of the electrodes and repeats stationary up-and-down motion at the particular voltage. The trapped position of the particle moves toward the wider gap side with the applied voltage. The electric field at the trapped position is almost constant, 1.8 MV/m. The comparision with the experimental trapped position and the calculated one is performed. From the simulation for the trapped position, when the charge amount which the particle acquired is a half of that predicted by induction, the calculated trapped position is well accordance with the experimental one.
Presentation Number: 11pC-8
Title: Development of Dielectrophoretic Filter for Elimination and Collection of Fine Particles Suspended in Liquid
Authors and Affiliation: Guangbin ZHOU, Manabu IMAMURA, Junya SUEHIRO and Masanori HARA@@Graduate School of Information Science and Electrical Engineering, Kyushu University
Abstract: Dielectrophoresis is the electrokinetic motion of dielectrically polarized particles in non-uniform electric fields. Dielectrophoresis has found many useful biotechnological applications including separation, levitation and characterization of dielectric particles and biological cells. In this study, the authors propose a new type of filter, which utilizes dielectrophoretic force to capture fine particles suspended in liquid. The filter consists of an electrode system that is filled up with many dielectric particles. The filled particles modify electric field distribution in the electrode system so that strong dielectrophoretic force is generated on their surfaces. If the dielectrophoretic force is stronger than drag force exerted by liquid flow in the filter, suspended particles can be trapped and eliminated from liquid flow. It was experimentally confirmed that proposed filter basically worked as designed. The filter can control trapping and releasing process just by changing application voltage and resultant dielectrophoretic force. 95% of yeast cells were continuously eliminated from suspension liquid.
Presentation Number: 11pC-9
Title: An Experimental Development of Environmentally Friendly Electret Filter
Authors and Affiliation: Masaharu NIFUKU*, Susumu SATOH**, Tadahiro KOBAYSHI, Yuan-Xiang ZHOU*** and Hiromi KATOH@@*Research Institute for Green Technology, National Institute of Advanced Industrial Science and Technology, **Niigata Plant, Toyo Roshi Kaisha Ltd., ***Department of Electrical Engineering, Tsinghua Universit
Abstract: Paying attention to the environmental impact, the authors tried to develop environmentally friendly electret filters. Polypropylene (PP) filter (non-woven, by melt blowing) and polytetrafluoroethylene (PTFE) filter were made as the samples. After investigating the charging characteristics of electrical charging methods, electret filters were manufactured in the laboratory experimentally. High voltage DC corona, pulse corona and pulse with DC corona were applied to investigate the charging characteristics. Pulse with DC corona, having higher charging characteristics, was applied to produce the electret filters. Surface charge density and dioctyl phthalate (DOP) collection efficiency were measured to evaluate the samples. PP electret filter showed higher collection efficiency 99.3% (pressure drop 17.5 mmH2O) and PTFE electret filter 97% (pressure drop 14.8 mmH2O) in the case of 0.1 ? 0.15Êm DOP collection (air velocity 5.3cm/s).
Presentation Number: 11pS-1
Title: Future of Intelligent robots
Authors and Affiliation: Hirofumi Miura@@Kogakuin University
Abstract: It should be understood that the robot is not a simple automatic machine, but instead has certain level of intelligence. Many kinds of intelligent robots have been developed in the author's laboratory from 1980fs to 1990fs. These robots perform many kinds of games like the cup & ball game, top-spinning, walking on stilts, etc. These robots apparently look intelligent, but are they really and truly intelligent? There is one opinion that these robots are no more than simple automatic machines which are controlled by a computer with sophisticated programs. If so, then what is actual robot intelligence? The author is trying to construct a new robotics --- insect-model based microrobotics --- in order to get a new concept of robot intelligence.
Presentation Number: 12aA-1
Title: Increase in Breakdown Strength for PE Film Using Additives of Aromatic Compound.
Authors and Affiliation: Megumi Ishigaki and Yoshiaki Yamano@@Faculty of Education, Chiba University
Abstract: An increase in dc breakdown strength (BDS) of LDPE film was studied using four kinds of additives. One group of additives includes Anthracene and Perylene. Another group of additives includes 9,10 Bromo-Anthracene and 1,7 Bromo-Perylene, in which Br radicals are connected to the each material in the former group. It was found that BDS was increased by using every additive. BDSs for the additives with Br radicals were higher than those for the additives without the radical. The additives with the radicals have no dipole moment because of these symmetrical structures. As far as the additive used in this study, the increase in BDS may not results from the following two effects: the effect of the electron scattering due to the dipole moment of the additive and the effect of the kinetic energy absorption due to the excitement of the additive. The experimental results suggested that the increase in BDS results from the effect of electron carrier trapping by the additives.
Presentation Number: 12aA-2
Title: Initiation of Tree Propagation from a Simulated Tree Channel inside LLDPE Prepared by Metallocene Catalyst
Authors and Affiliation: Kuniharu IMAI@@School of Health Sciences, Nagoya University
Abstract: Transmission voltage tends to rise with increase of electrical power demand, so that treeing degradation in insulation of power cable occurs easier than before. Improvement of insulating material is indispensable for dealing with this problem. Recently, polyethylene prepared by metallocene catalyst (metallocene-PE) is in spotlight in high voltage engineering, because it has excellent molecular characteristics. Therefore researches concerning with electrical conduction and breakdown characteristics in metallocene-PE have been carried out. In order to use metallocene-PE as insulating material of power cable, it is very important to clarify treeing degradation properties in it. However investigations on treeing degradation have been hardly performed. In previous studies, I made a simulated tree channel inside polymer material and examined the tree growth characteristic. In this study, I made a simulated tree channel in linear low-density polyethylene (LLDPE) synthesized by metallocene catalyst and investigated on initiation characteristic of tree propagation from its tip. The initiation characteristic in low-density polyethylene (LDPE) prepared by Ziegler-Natta catalyst was also examined for reference. Inception voltage of tree propagation in LLDPE is higher than that in LDPE. In order to clarify effect of the metallocene catalyst, structural analysis using Raman spectroscopy and X-ray diffraction (XRD) analysis was carried out. These spectrum patterns for LLDPE are the same as those for LDPE. It is apparent that crystallinties of two kind of films make little difference. From reference to standard pattern of XRD spectrum, it is evident that structures of two samples are monoclinic system. Full-width at half maximum (FWHM) of XRD spectrum for each crystal plane in LLDPE was wider than that in LDPE. The crystal plane of LLDPE is found to be thin. Reason why Inception voltage of tree propagation in LLDPE is higher than that in LDPE is considered that structure of LLDPE is more homogeneous.
Presentation Number: 12aA-3
Title: An@Equivalent@circuit for Zinc Oxide Varistors
Authors and Affiliation: Mahmudul KABIR, Masafumi SUZUKI and Noboru YOSHIMURA@@Department of Electrical and Electronic Engineering , Akita University
Abstract: After sanding of some ZnO varistors' surfaces, we observed of their internal structure by a simple microscope. We measured the samples' electrical and electrostatic capacity properties. Thus observed varistor voltage was 13.50[V] for the sample A sintered at 1320 in air. Considering varistor's characteristics and measured electric properties ; we made a simple equivalent circuit for the sample which was analyzed by Spice Circuit Simulator.
Presentation Number: 12aA-4
Title: Development of Charged Mist Generator using a Rotating Disk
Authors and Affiliation: ßHiroshi YAHATA, Makoto SUGIYAMA, Kazunori TAKASHIMA, Shinji KATSURA, and Akira MIZUNO@@Department of Ecological Engineering, Toyohashi University of Technology
Abstract: The authors developed a new charged mist generator that can be applied to various field. In this system, water was dropped on the disc that was rotated by a DC motor, resulting in the atomization by the centrifugal force. At the same time, when high voltage was supplied to the water, charged mist was generated. The particle diameter of generated mist in this system were several tens to several hundreds micro meter. And when high voltage was applied, smaller mist was generated. As a result of the dust collection test using charged mist spray system, much higher collection efficiency was observed compared to that with uncharged mist.
Presentation Number: 12aA-5
Title: Effect of water flow rate on diameter and charge of water droplets generated by electrostatic atomization
Authors and Affiliation: Jun Nagata and Yuji Murata@@Science University of Tokyo, Faculty of Science & Technology
Abstract: Effect of water flow rate on diameter and charge of water droplets generated by electrostatic atomization were measured by taking care of the effect of ions generated at the same time. The water droplets are jetted from a vertical needle to which high potential is applied. They fall down by forming a corn-shape trajectories. In the case of needle electrode of that the inner diameter is 0.8mm, the charge and the diameter of the droplets were scarcely affected by the water flow rate between 0.1`0.8ml/s. However, diameter of the droplets became large when needle electrode of larger inner diameter was used.
Presentation Number: 12aA-6
Title: Effects of induced voltage on the large ion which arises from water jet
Authors and Affiliation: Hirofumi SHIMOKAWA@@Kanagawa Institute of Technology
Abstract: It is known that the negative charged fog arises in the circumference of the water jet, when the water is ejected from the nozzle. The quantity of the charged fog increases with the purity of the water. This report examined the effects of induction field on generation rate of the negative or positive charged fog. It was found that the chaged fog increased over the 2 doigits, when the induction field is applied, and that the much charged fog arises in spite of the purity of the water. From the result, it is discussed that the position of he electrode greatly affects the generation of the charged fog.
Presentation Number: 12aB-1
Title: Plasma Reforming and Coupling of Methane with Carbon Dioxide
Authors and Affiliation: Shuiliang YAO, Mamoru OKUMOTO, Akira NAKAYAMA, Eiji SUZUKI@@Catalysis Sicience Lab.. Research Institute of Innovative Technology for the Earth(RITE)
Abstract: Plasma reforming and coupling of methane with carbon dioxide using a point-to-point type of reactor have been investigated. A feed mixture of CH4 and CO2 could be converted mainly to CO, H2, and C2H2, at atmospheric pressure and without external heating except plasma heating. Under a condition of 200 ml/min of CH4 and CO2 (CH4:CO2 volume ratio= 50:50), 2.5 mm discharge gap, and pulse frequency of 10.3 kPPS, CH4 and CO2 conversion were 65.9 % and 57.8 %, respectively. C2H2 selectivity and H2/CO ratio could be moderated by changing CH4 concentration in the feed mixture.
Presentation Number: 12aB-2
Title: Generation@of Hydrogen from Methane and Water in a Dielectric-Barrier Discharge-Plasma System.
Authors and Affiliation: Kanji IRIE, Takasumi SHIMIZU, Toshiyuki WATANABE@@Daido Steel Co.,Ltd., Nagoya,Aichi,Japan
Abstract: The decomposition of CH4 was investigated in a dielectric-barrier discharge-plasma system. Effects of new electrode named spiral electrode was studied in a dielectric-barrier discharge-plasma system. The discharge can be formed between the 2mm gap with about 20 kVp-p sin-wave and other pulsed wave( `10 kHz). We found frequency effect H2 product rate prominently by applying spiral electrode compared with conventional electrode of tublar type dielectric-barrier discharge-plasma. Most effective frequency was 3kHz to generate H2 from CH4 with waterDThe maximum CH4 conversion of 80% into H2 was achieved in the absence or presence of water. The other major products observed were CO and CO2. Even though using this spiral electrode, hydrogen yield degraded on the condition of high velocity of gas . For the purpose of getting good yield of hydrogen Plasma assisted catalytic technology systems have been expected to develop.
Presentation Number: 12aB-3
Title: Hydrogen Generation from Small Molecules with Nonthermal Plasma
Authors and Affiliation: ?Shigeru FUTAMURA, Hajime KABASHIMA, and Hisahiro EINAGA@@National Institute of Advanced Industrial Science and Technology
Abstract: Hydrogen generation from small molecules such as water, methane, and methanol was investigated with a ferroelectric packed-bed reactor (FPR) and a silent discharge plasma reactor (SDR). In N2, the reactivities of the above compounds decreased in the order: methanol > methane > water. Interestingly, higher H2 yields were obtained with FPR at the same specific energy densities (SEDs). Higher H2 yields were obtained at shorter residence times at the same SEDs. Backgroiund O2 was detrimental in increasing H2 yields.
Presentation Number: 12aB-4
Title: Treatment of waste water using water droplets by pulsed power discharge.
Authors and Affiliation: Yasushi MinamitaniC Yuri OkamotoCand Yoshio Higashiyama@@Faculty of Engineering, Yamagata University
Abstract: Since non-thermal plasma is able to produce high-energy electrons, free radicals and UV having high chemical reactions, atomizing water into the plasma can be expected high treatment in the water remediation. The experiment for water treatment in the water remediation was carried out by injecting water droplets into the non-thermal plasma generated by pulsed power in air. The used sample is 0.1% water solution of sodium dedecylbenzensulfonate (C12-LAS). The repetition rate of pulsed discharge and the passing time of water droplet were set as the discharge exposes the water droplet once. The discharge voltage and current in the water droplet were nearly equal in air. In this conditionC the pulsed discharge made the concentration of C12-LAS below 20%.
Presentation Number: 12aB-5
Title: Mechanism of Decoloration of Dyes by Pulsed Discharge Plasma in Water
Authors and Affiliation: Anto Tri Sugiarto,Takayuki OOSHIMA, Masayuki SATO@@Department of Biological & Chemical Engineering Gunma University
Abstract: The pulsed streamer corona discharge in water has been investigated for the decoloration of aqueous dye solutions. The reactor with ring-to-cylinder electrode system has been designed and examined in this investigation. It was found that the pulsed discharge plasma is possible to decoloration of dyes in water solution. The decoloration mechanism of dye was investigated using high performance liquid chromatography. Hydroquinone, and p-benzoquinone were found to be byproducts of Phenol red decomposition during pulsed discharge plasma treatment. It can be considered that the decoloration occurred by breakup of the bonds between chromophores by radical reaction in plasma region.
Presentation Number: 12aB-6
Title: Fundamental Study on Waste Water Treatment Using Corona Discharge Over Water
Authors and Affiliation: Yasutomo FURUTA and Fumiyoshi TOCHIKUBO@@Department of Electrical Engineering, Tokyo Metropolitan University
Abstract: A Corona discharge over water is applied for decolorizing the ink-water and the decomposition of NH4-N. The decolorizing characteristic of ink-water depends on the total supplied energy. The discharge with shorter gap showed the better energy efficiency of decolorizing. The concentration of NH4-N reduced from 11 mg/L to 5 mg/L leading the generation of NO2-N and NO3-N when pH of the solvent is set to be 11.2 although it did not change without controlling the pH.
Presentation Number: 12aD-1
Title: Electrostatic Field Strength Detecting System for Powder Handling Processes
Authors and Affiliation: Tsutomu KODAMA, Satoru WATANO, Teruo SUZUKI and Tomohumi MOGAMI@@National Institute of Industrial Safety, Independent Administrative Institution Dept. Chem. Eng., Osaka Prefecture University Kasuga Denki INC
Abstract: Recently, electrostatic hazards and troubles have become a serious problem in powder handling processes. Continuous monitoring and control of static electricity are required in order to solve these problems. In this study, performance of the improved air-purge type electrostatic field sensor which equips with an air-curtain function for preventing charged powder from attaching to the sensor was investigated using a experimental set-up composed of a real-sized fluidized bed, a silo and a powder pneumatic transport system. As a result, the improved electrostatic field strength detecting system was found to be useful for electrostatic monitoring in powder handling processes.
Presentation Number: 12aD-2
Title: Development of a feedback charge control system in powder pneumatic conveying process
Authors and Affiliation: Seiji SAITO@@Department of Chemical Engineering, Osaka Prefecture University
Abstract: In a powder pneumatic conveying process, powders are remarkably charged due to the collisions between powders and conveying pipe, which sometimes causes explosion and fire. Therefore, development of a reliable system for charge control in a powder pneumatic conveying process is strongly required. In this study, an electrical charge feedback control system composed of a corona discharge neutralizer and an electrostatic filed strength sensor was newly developed and applied to the powder pneumatic conveying process. Performance of the system was investigated experimentally under various control parameters (PID control). It was found that the electrical charge during powder pneumatic conveying process was favorably controlled by means of PID feed back control system.
Presentation Number: 12aD-3
Title: Discharge model for charged powder loading simulation
Authors and Affiliation: Atsushi OHSAWA@@National Institute of Industrial Safety
Abstract: We report preliminary simulation of charged powder loading with taking account of discharges in a vessel. We have conducted the simulation of charged powders being filled with vessels to evaluate electrostatic hazards. The previous model neglected discharges. The model, therefore, could not evaluate truly the hazards, although the possibility of discharges could be evaluated. We present a simple model for discharge as well as charge relaxation. Our discharge model is that if local electric field is greater than the breakdown field for air, the charges on the powder particles in the local region are gradually neutralized until the field is smaller than the breakdown field. To confirm the validity of the model, we apply the model to the charged powder loading simulation in monodispersed particles of 1 mm and a small vessel with 0.5 m in height and 0.5 m in diameter.
Presentation Number: 12aD-4
Title: Influence of Diameter of a Grounded Sphere Electrode on Electrical Discharge Occurring toward a Charged Particles Cloud
Authors and Affiliation: Yoshio HIGASHIYAMACHiroyuki KIKUCHICand Toshiyuki SUGIMOTO@@Department of Electrical EngineeringCYamagata University
Abstract: The electrical discharge occurring from a grounded electrode around a space charge cloud formed with charged particles was investigated experimentally. The sieved particles with diameters ranging from 53 to 250 mm and from 250 to 500 mm were charged with dc corona and were ejected upward with a speed of a 35 m/s in a cubic space with a side length of 5.4 m. The time variations of the electric field strength around a charged cloud were measured with five field mills simultaneously. The discharge was periodically occurred and a number of streamers widely extended from the grounded electrode toward the cloud. The maximum length of the streamers, the time interval of discharges, and the magnitude of the discharge current strongly depend on the diameter of the grounded sphere electrode as well as the sizes of the charged particles forming a particle cloud.
Presentation Number: 12aD-5
Title: On the ignition limit curves of spark ignition circuits
Authors and Affiliation: Atsushi OHSAWA* and Mikio OHUCHI**@@*National Institute of Industrial Safety,
**Faculty of Engineering, Tokyo Denki University
Abstract: We suggest the theory for ignition limits of spark ignition circuits. The curves of the ignition limits have non-linearity. Moreover according to the limits, minimum ignition energy derived from discharge energy is dependent on circuit element constants, although the minimum ignition energy should be constant. To explain the non-linearity and the contradict in the minimum ignition energy we introduce the characteristic time required for initiating an ignition into the theory. The characteristic time, which may depend on the conditions of combustible atmosphere, means energy transfer time for ignition. The essence of the theory is that the energy transferred into the atmosphere during the characteristic time is effective for ignition. We applied the theory to simple circuit model for ignition. The results showed that the model expressed well the shapes of the ignition limit curves having non-linearity in resistive, capacitive and inductive ignition circuits, although the model was very simple.
Presentation Number: 12aD-6
Title: Charging of Human Body at Walking
Authors and Affiliation: Hirotaka Nakamura@@Tokyo University of Agriculture and Technology
Abstract: The human body is charged easily by friction between floors and shoes. The discharge from the charged human body often causes computer malfunction and destruction of semiconductor devices. The change in the potential of the human body is measured, when the person walks on the floor. Four kinds of shoes are used : slippers, sports shoes, leather shoes, Antistatic-electrostatic footwears. A polyvinyl chloride floor and a polyester floor are used. Relative humidity of the room is changed from R.H 30% to R.H 70%. The experimental result shows that the potential of the human body decreases as relative humidity of the room rises. At high relative humidity, the Antistatic-electrostatic footwears are especially effective to suppress the potential : It is below 60V at R.H.70%.
Presentation Number: 12aD-7
Title: Prevention of Static Charging on Conductive Glass-Lined Equipment (W)
Authors and Affiliation: Takashi KAWASHIMA, Tsutomu KODAM A, Mizuki YAMAGUMA and Tomohumi MOGAMI@@Ikebukuro Horo Kogyo Co., Ltd. National Institute of Industrial Safety, Independent Administrative Institution Kasuga Denki Inc
Abstract: In order to investigate performance of the newly developed conductive glass-lined conical dryer for preventing charge accumulation on the glass lining (GL) the static charging tendencies were compared between two types of 100L capacity of conical dryers with conductive and insulating GL, respectively. In experiments the surface potential on the GLs was measured with an air-blow type electrostatic field meter throughout the rotating operation of the dryers including test particles, PP pellet or polished rice. The surface potential obtained on the conductive GL was 20% lower than that on the insulating GL when the particle was polished rice with a relatively low resistivity.
Presentation Number: 12aS-1
Title: Measuring Electrostatic Phenomena on Mars and the Moon
Authors and Affiliation: C.I. Calle@@Electromagnetic Physics Laboratory, NASA Kennedy Space Center
Abstract: Telescopic observations of Mars and the moon date from 1610, when Galileo turned his first telescope to the heavens. It was not until spacecraft began to orbit and eventually land on these two bodies that a more accurate understanding was obtained. NASA's Apollo program to the moon brought twelve astronauts to its surface and returned lunar samples to earth for detailed studies. This paper will summarize our current understanding of the electrostatic properties of the martian and lunar regoliths. Ground based laboratory experiments to understand the electrostatic properties of these regoliths as well as those of the martian atmosphere will be summarized. The design and construction of a flight instrument to measure the electrostatic response of several polymers when exposed to martian soil and dust will be presented.
Presentation Number: 12pA-1
Title: Polymer Charging with Regolith Simulant Particles at Martian Environmental Conditions
Authors and Affiliation: C.I. Calle1, J.G. Mantovani2, C.R. Buhler3,and E.E. Groop1@@1 Electromagnetic Physics Laboratory, NASA Kennedy Space Center, YA-F2-T, Kennedy Space Center, FL 32899, USA
2Department of Physics and Space Sciences, Florida Institute of Technology.
Abstract: Andesite particles from Hawaiian volcanic ash which simulate the Martian regolith were rolled over five polymers under simulated Martian environmental conditions to study the electrostatic response of these polymers to granular material that may be encountered during a Mars landing mission. A mission-ready flight instrument consisting of five electrometer sensors, capped with the five polymers, was used to measure the electrostatic charge generated on the polymers as the simulant particles were rolled back and forth along their surfaces. The martian atmospheric environment at the surface of the planet was partially simulated in a vacuum chamber using CO2 at 9 mbar and room temperature. The weight of the simulant particles on the polymer surfaces generated charges of the order of 20 pC on the 6 mm-diameter polymer surfaces.
Presentation Number: 12pA-2
Title: Nonlinear ionic-conductivty of triethylene oxide attached with mesogenic 4-c yano-4'-hydroxybiphenyl group as an end group
Authors and Affiliation: Yoshiro TAJISTU@@Dept. of Polymer Sci. & Eng., Fac. of Eng., Yamagata University
Abstract: We have discussed the mechanisms of ion transport in the ion-conducting polymers on the basis of the results of nonlinear conductivities. The results obtained are very much in agreement with the prediction of dynamic percolation model. Considering all the aspects of a problem to obtain the ion-conducting polymers with the higher conductivity, we contrive a method to make a high conductivity in ion-conducting polymers. In this paper, we report on the synthesis of a new type ion-conducting polymers, poly(ethylene oxide) modified with mesogenic group, and the measurements of the frequency spectra of linear and nonlinear conductive spectra. We obtained triethylene oxide attached with mesogenic 4-cyano-4'-biphenyl group as end group (abbreviated as CYBPEO) and added with KCl. The evaluated dc-conductivity is over than 10-2S/m. The existence of the large conductive relaxation process has been observed in CYBPEO/K+.
Presentation Number: 12pA-3
Title: Change in Charging Characteristics of Polyethylene by Remote Plasma Treatments (W)
Authors and Affiliation: Masakazu ABE, Kazutaka ARAI and Yuji MURATA@@Science University of Tokyo, Faculty of Science & Technology
Abstract: The characteristics of polymer surface can be changed by plasma treatment. We have found that low-density polyethylene (LDPE) films treated by N2 remote-plasma showed positive or negative charging tendencies depending on the treating position in the plasma chamber. In the present study, we investigated the effect of remote plasma treatments as functions of treatments pressure, amount of flowing gas and radical life.
Presentation Number: 12pA-4
Title: Frictional Electrification between LB Films and Dipole Momenof Constituent Molecules
Authors and Affiliation: Keiji OHARA, Isao NAKAMURA and Taku HIRAI@@Faculty of Textile Science and Technology, Shinshu University
Abstract: Frictional electrification between LB films was investigated.Triboelectric series of LB films was constructed. Dipole moment of constituent molecules of LB films was obtained by measuring the displacement currents during compression of L layer on the water surface. The magnitude of dipole moment decreased in the order of the molecules in the triboelectric series.
Presentation Number: 12pA-5
Title: Change in Charging Characteristics of Polymer Surface by Corona Treatments and itsDependence on Relative Humidity
Authors and Affiliation: Yusuke ONODA, Yuji MURATA@@Science University of Tokyo, Faculty of Science & Technology
Abstract: The charging characteristics of polymer surface are changed more negatively by corona-treatment, and its characteristics are highly affected by relative humidity of ambient air during the treatment. When the corona power is constant, charge density on the sample surface treated in the air at 90%RH is several times as large as that at 10%RH. In the case of constant corona power, applied voltage must be increased as the relative humidity increases. The change in the effect of corona-treatments to the relative humidity is discussed from the viewpoint of kinetic energy of ions.
Presentation Number: 12pA-6
Title: Change in Charging Characteristics of Polyethylene Powder Particles by Plasma Treatment in Atmospheric Pressure(U)
Authors and Affiliation: Toshiyuki NAGASAWA and Yuji MURATA@@Science University of Tokyo, Faculty of Science & Technology
Abstract: We investigated the change in charging characteristics of contact and frictional charging of polyethylene powder by plasma treatment in atmospheric pressure. We have carried out this treatment using barrier discharge. Furthermore, in order to improve treatment efficiency, we used streamer corona discharge system. As a result, the treatment time was shortened by 1/5 than that before.
Presentation Number: 12pA-7
Title: Change in Charging Characteristics of Polyethylene Powder by Ar plasma Treatments (V)
Authors and Affiliation: Junichi Okubo, Yuji MURATA@@Science University of Tokyo, Faculty of Science & Technology
Abstract: Plasma treatment of the polyethylene powder particles was carried out in argon gas. The glass beads of diameter larger than that of powder particles were put in a container for treatment with powder particles and plasma treatment was carried out with the container rotating. Using this method, all powder particles were uniformly treated. As a result, the specific charge of powder particles generated by friction with glass beads increased by 20 times as large as the value before treatment by 30 seconds plasma treatment with electric power of 0.55 W. And the specific charge obtained by the treatment using metal container increased by 1.4 times as large as the value obtained by the treatment using glass container.
Presentation Number: 12pB-1
Title: Treatment of Activated Carbon for the Modification of its Adsorbability Using Dielectric Barrier Discharge
Authors and Affiliation: Hidetoshi SEKIGUCHI and Satoshi KODAMA@@Department of Chemical Engineering, Tokyo Institute of Technology
Abstract: Granular activated carbon was treated by oxygen dielectric barrier discharge to improve its adsorbability for metal ions. The analytic results for the activated carbon treated by the plasma showed the decrease in its surface area and the increases in the concentrations of acidic functional groups on the surface. The experimental results of the adsorption showed that the adsorbability of the activated carbon for Cu and Zn ions was improved by the plasma treatment and the saturated adsorption amount was increased largely. The plasma treatment of activated carbon was considered as an effective method for the improvement of adsorbability.
Presentation Number: 12pB-10
Title: Concentrating Nonthermal Plasma Desorption of NOx in Flue Exhaust Gas
Authors and Affiliation: Masaaki OKUBO, Goichi TANIOKA, Tomoyuki KUROKI@and Toshiaki YAMAMOTO@@Department of Energy Systems Engineering, Osaka Prefecture University
Abstract: The gas flow rates for hazardous air pollutant emissions are generally large and their concentrations are low (in ppm levels). When we try to treat directly the large flow rate and low concentration exhaust gas, the size of the equipment becomes large, resulting in high operating cost. The objective of this study is to convert the exhaust gas with large flow rate and low concentration into the one with small flow rate and high concentration by desorbing the absorbed gas from the absorbent pellets packed inside a barrier-type packed-bed nonthermal plasma reactor. In this report, we especially focused on difficult to treat NOx. The absorbent pellets were molecular sieve spheres (MS-13X) made of zeolite with 1 nm pore diameter. The plasma desorption was carried out by applying the high voltage to the plasma reactor using any one of AC 60 Hz, AC 20 kHz or pulse 210 Hz power supplies. We found out that NOx could be desorbed effectively in the repeated adsorption and desorption process. It was succeeded for the first time to achieve a nonthermal plasma concentrating desorption of NOx as the adsorption /desorption was repeated more than 12 times.
Presentation Number: 12pB-2
Title: Decomposition mechanism of dioxins under the irradiation of@electron-beam using a model compound.
Authors and Affiliation: Hyun-Ha Kim, Teruyuki Hakoda, Takuji Kojima, Masakazu Tanase@@Japan Atomic Energy Research Institute (JAERI)
Abstract: Decomposition of dioxin under electron-beam irradiation has been@investigated using a lab-scale flow type reactor at 200. We used diphenyl ether (DPE) as a model compound of dioxin because the chemical structure of@DPE is similar to the PCDD/F. Experimental results indicated that the radical species from oxygen play an important role in the decomposition of@DPE. Results from the byproduct analysis suggest that the main breakpoint is ether bond (C-O) between the rings. Hydroquinone(HQ) and dibenzofuran(DF) were found to be the major ring retaining products resulting from the decomposition of DPE. Addition of ozone enhanced the decomposition while no enhancement by adding water vapor. The presence of NO decreased the decomposition efficiency of DPE.
Presentation Number: 12pB-3
Title: SO2 removal using electrostatic spray method
Authors and Affiliation: Azuchi HARANO, Takuya TADENUMA, Takayuki TAKARADA@@Faculty of Engineering, Gunma University
Abstract: The De-SOx process using electrostatic spray is a very attractive method to satisfy the request of the developing countries because this processes do not need a large amount of water and the large space area to construct. We obtained the high desulfurization efficiency by the addition of H2O2 into droplets in the case of liquid/gas ratio about 0.2[l/Nm3] which value is so small as to be one tenth of that of a general wet desulfurization process. But this process has a cost problem about SO2 oxidative additive of H2O2. The present report is concerned with basic characteristics of the new economical additives for desulfurization process. From our experiments, the NO2 is very effective additives for the SO2 oxidation into aqueous droplets. NO2 is excellent in cost because NO2 can easily obtained from oxidation of NO in exhaust gas. We present the possibility of De-SOx process using NO2 in this report.
Presentation Number: 12pB-5
Title: Comparison of Plasma Reactors on NO Removal from Diesel Engine Emission
Authors and Affiliation: T. Yamamoto, M. Okubo, T. Kuroki and M. Nishino@@Dept. of Energy Systems Engineering, Osaka PrefectureUniversity
Abstract: We investigated a relative comparison of several discharge plasma reactors from NO removal efficiency. The reactors were either energized by AC or by repetitive pulses. Ferroelectric pellets were used to study the effect of pellet assisted discharges on gas cleaning. Diesel engine exhaust, at different loads, is used to approximately simulate the flue gas composition. Investigations were carried out at room temperature with respect to the variation of reaction products against the discharge power. Main emphasis focused on the oxidation of NO to NO2, without reducing NOx concentration (i.e., minimum reaction byproducts), with least power consumption. The produced NO2 will be totally converted to N2 and Na2SO4 using Na2SO3. The AC packed bed reactor and pelletless pulsed corona reactor showed better performance, with minimum reaction products for a given power, when the NO concentration was low (`100 ppm). At high engine loads (NO > 300ppm) there was not much decrease in NOx reduction and more or less all the reactors performed equally. The paper discusses these observations in detail.
Presentation Number: 12pB-6
Title: After Treatment of Diesel Engine Exhaust using Non-thermal Plasma
Authors and Affiliation: Yoshihiko MATSUI, Souichirou KAWAKAMI, Zhenzhou SU, Kazunori TAKASHIMA, Shinji KATSURA and Akira MIZUNO@@Department of Ecological Engineering, Toyohashi University of Technology
Abstract: Simultaneous removal of NOX and carbon soot from diesel exhaust has been experimentally studied. In this study, the filter type and the pellet type plasma reactors driven by pulsed and AC high voltage were tested. Diesel engine exhaust and the simulated gas were used for the test. Carbon soot was collected on the glass cloth or surface of the g-Al2O3 pellet by electrostatic precipitation. The collection efficiency for 0.6Êm-diameter particle was about 95% at the specific input energy (SIE) of 3.0J/L in the cloth-type plasma reactor. In the pellet type plasma reactor, 74% of carbon soot was collected at the specific input energy (SIE) of 4.0J/L. Carbon soot was oxidized to CO2 by the pulsed or AC discharge at the SIE of 50-60J/L using the pellet type reactor.
Presentation Number: 12pB-7
Title: Simultaneous Removal of Particulates, NOx and SOx Using the Pulse Plasma-Chemical Hybrid Reactor
Authors and Affiliation: Tomoyuki KUROKI, Masayoshi TAKAHASHI, Nobuaki NAKANO, Masaaki OKUBO and Toshiaki YAMAMOTO@@Dept. of Energy Systems Engineering, Osaka Prefecture University
Abstract: In previous study, we investigated the simultaneous removal of NOx and Sox using plasma-chemical hybrid process and showed nearly 100% NOx and SOx removal. In this study, we investigated simultaneous removal of NOx, SOx and particulates using a single-stage wet-type plasma-chemical reactor. This reactor consists of discharge wire and pyrex cylinder, wrapped by the copper mesh where Na2SO3 and NaOH solutions flow along inner wall of cylinder from the top to the bottom of the reactor. It is feasible for particulates to be charged by pulse corona and collected on the inner wall, and then removed by solutions flow. The plasma was used to oxidize NO to NO2, Na2SO3 solution to reduce NO2 to N2 and Na2SO4, and NaOH solution to absorb SO2 and to neutralize nitric acid ions in the solution. Without Na2SO3 and NaOH solutions, 95% NO removal was achieved at 2.5 W. With water, 97% NO and 63% NOx removal were achieved at 2.6 W, and more than 95% SO2 removal was achieved regardless of the discharge voltage. With water Na2SO3 and NaOH solutions, 98% NO and 75% NOx removal were achieved at 2.9 W, and more than 93% SO2 removal was achieved regardless of the discharge voltage.
Presentation Number: 12pB-8
Title: NOx Oxidation-Storage using Discharge Plasma with BaO Catalyst and
its Reduction using Electrodialysis
Authors and Affiliation: Zhenzhou Su, Azlin Takin, Yoshihiko Matsui, Kazunori Takashima, Shinji Katsura, and Akira Mizuno@@Department of Ecological Engineering, Toyohashi University of Technology
Abstract: A novel reduction process for deNOx was investigated in this study. In the NOx storage process, 80% of NO (initial concentration of 210ppm) was oxidized to NO2 by the pulsed plasma with the specific input energy of 45J/L. NOx storage to the alkaline-earth metals was confirmed. The mechanism of the NOx storage was investigated using XRD. The reduction of absorbed NOx using the dc-voltage application was suggested from the experimental results.
Presentation Number: 12pB-9
Title: NO Decomposition in O2/N2 using Adsorption of Catalyst and Plasma
Authors and Affiliation: Naohiko GOTO, Satoshi KUDOU, Seiichi OHYAMA, and Hideki MOTOYAMA@@Central Research Institute of Electric Power Industry
Abstract: NO direct decomposition has been investigated in a packed bed pulsed barrier discharge with copper ion-exchanged ZSM-5 zeolites (Cu-ZSM-5) in flowing NO/O2/N2. After NO is adsorbed on Cu-ZSM-5 in flow with 200ppm of NO, 9% of O2, and N2, the Cu-ZSM-5 with adsorbed NO is treated by a barrier-discharge plasma in N2. As a result of the discharge, NO conversion efficiency is about 46%, and NO2 and N2O generation efficiency is only about 5% and 4%, respectively. Since the total amount of NO, NO2, and N2O decreases at outlet of reactor, about 37% of NO is directly decomposed to O2 and N2.
Presentation Number: 12pD-1
Title: Low Cost Cord DC Neutralizers
Authors and Affiliation: Alok Chakrabarti@@Simco Japan
Abstract: Further investigation into the performance of cord bars have been carried out. A comparative study with other DC and AC bar neutralizers have been made and results presented. The neutralization efficiency and ion balance have been measured with the addition of air flow and found to have improved significantly. Air flow helps to increase the working distance and keep the cords relatively clean. Long time ion balance stability with air flow is very good and can be maintained under +/-50V. The use of Simco's special power supply provides stability and smooth control over the ion balance voltage. This type of neutralizers and power supply, originally conceived for web applications, would be economically attractive and might be used in many other applications.
Presentation Number: 12D-2
Title: Static Elimination Under the Low Air Pressure
Authors and Affiliation: Nobuo Nomura, Yoshitsugu Okamura, Kenji Horikiri, Kazuaki Nakajima@@KASUGA DENKI, INC.
Abstract: It is general to use the static eliminator for eliminating the static created under the normal air pressure. There are many studies and reports on the method of static elimination under the normal air pressure. But there is little study and report on the static elimination under the low air pressure. We used the vacuum chamber which can make the pressure down to 10Pa to examine the static elimination under the low air pressure. We measured the discharge current at the charge plate, which was set at front of the resistor-coupled static eliminating electrode in the vacuum chamber. Also we measured the static elimination capability with the film, which was positively or negatively charged in the same chamber. From these experiments, we found out that the discharge current flew about 40times more at approximately 100Pa compared with the normal air pressure. Also we found out that it is possible to remove the static marks from the highly positive and negative charged film in the low air pressure without using our patent granted high density ionizing systems (We reported this system at this seminar in October, 1996).
Presentation Number: 12pD-3
Title: Deterioration Characteristics of Corona-Discharge Emitter Composed of Single Crystal Silicon
Authors and Affiliation: Soichiro@SAKATA@and@Atsushi@TAKAHASHI@@R & D Center, Takasago Thermal Eng., Co., Ltd.
Abstract: We have developed an air ionizer using single crystal silicon emitters corona-discharging at 6kV AC voltage of 50/60Hz. The particle count of above 0.05Êm at 22 cm distance from the emitter point was 2 /ft (superscript: 3) at most during the continuous 10-month operation in the 0.35m/s downflow cleanroom with the atmospere of (23}2) and (40}10)%RH. With the UHR-FE-SEM and EPMA analyses regarding the axial cross section of the emitter point, we found that the silicon oxide layer of a few microns in thickness prevented oxygen in the surrounding air from diffusing into the single crystal silicon consisting the emitter point. The silicon oxide layer around the point blocked the deterioration of the single crystal silicon emitter point due to the oxidation. As a result, the particle generation with a size of 0.05Êm or more could be scarcely measured.
Presentation Number: 12pD-4
Title: Generation of ionic space using atomized water droplets charged by AC corona discharge
Authors and Affiliation: Atushi Yokoyama and Yuji Murata@@Science University of Tokyo, Faculty of Science & Technology
Abstract: In order to prevent electrostatic hazard, the space ionization method was investigated by generating fine water droplets charged by AC corona discharge. By using this method, ion density in the air a part from the ion generator was considerably increased in comparison with the case without water droplets.
Presentation Number: 12pD-5
Title: Corona Characteristics of Conductive Fibers
Authors and Affiliation: Changrag CHOI, Yuji MURATA and Kohei YAMADA@@Faculty of Science & Technology, Science University of Toyko, Daiwa Co. Ltd.
Abstract: In the case of the self-discharge type charge elimination, ions are generated through corona discharge at the tip of conductive fine fibers under the effect of strong electric field produced by electrostatic charge on the body to be charge-eliminated. The corona characteristics of several conductive fibers has been investigated in order to obtain the fundamental information on this phenomenon. The corona onset voltage of finer-diameter fiber was lower than that of thicker-diameter fiber. The corona onset voltage of finest fiber (diameter of fiber:14Êm) used in the present experiment was 1.7kV. The corona onset voltage of thickest fiber (diameter of fiber : 658Êm) was 3.1 times as high as that of finest fiber. As the corona discharge was continued, the corona characteristics for all conductive fibers was changed and the corona offset voltage was higher than the corona onset voltage. The difference between onset and offset voltage of corona discharge could be explained that the shape of the tip of each fiber is changed by the concentration of discharge current.