Abstract　of　All　Papers　Presented　to 2004 Annual Meeting of The Institute of Electrostatics Japan

 

(Followings are presentation number, title, authors, their affiliations and abstract for each paper)

 

16aB-1 

Removal of formaldehyde in the corona discharge with needle electrode and the catalyst honeycomb

Mitsubishi Electric Corporation   

Takuya FURUHASHI, Akira SHIGA, Shiro TAKEUCHI and Yoji FUJITA      

The removal rate of formaldehyde, the ozone generation and also the conversion rate of formaldehyde to carbon dioxide in the corona discharge reactor was investigated. This reactor was composed of a needle discharge electrode and a conductive manganese oxide catalyst honeycomb. The result showed there was an optimal needle configuration for the maximum formaldehyde removal and the least ozone generation. Moreover, the conversion rate of the formaldehyde to the carbon dioxide at the optimal needle configuration was proportional to the square root of the relative specific input energy.   

 

16aB-2

Examination of conversion of paraffin into olefin by electrical discharge plasma

Mitsubishi Electric Corp. Advanced Technology R&D center 

Masato KURAHASHI, Hiroaki SHIGEOKA, Sho SHIRAGA, Minoru SATOH, Kazuhiko KAWAJIRI and Masaki KUZUMOTO      

Conversion of paraffin into olefin by electrical discharge plasma has been studied. Propane as paraffin is diluted by Air consists of 90% nitrogen, 10% oxygen and 28,000ppm water，and propane concentration is 500ppm. O* and OH* radicals are generated by electrical discharge in a coaxial barrier discharge reactor which is keeping at 600℃. Propane is oxidized by radicals and converted into propene and ethylene. Olefin with a concentration of 180ppm are generated　with specific energy density of 46.8J/L. When the temperature of the reactor is under 550℃ small amount of olefin are generated. Up to 650℃, olefin are decreased　and　CO and CO2　are　generated　from　olefin.

 

16aB-3 

Formation of Charged Particles in Air Containing o-Xylene under Electron Beam Irradiation

Takasaki Radiation Chemistry Research Establishment, Japan Atomic EnergyResearch Institute        

Teruyuki HAKODA, Akihiko SHIMADA and Takuji KOJIMA           

Electron beam (EB) irradiation of aromatic hydrocarbons and humid air mixtures leads to toxic particles in the size of about 100 nm and gaseous organics such as organic acids. The particles should be removed from gas phase, for example using electric field after their charging, for the detoxification of irradiated air mixtures. In the present work, a few tens keV electron generator was developed to study the formation process of charged particles in irradiated humid air containing o-Xylene at initial concentrations of 10 and 30ppmv. After EB irradiation to an absorbed dose of 9.8 kGy, yields of particles and gaseous organic were 65-68% and 16-17% of irradiation products on the basis of carbon, respectively. Yield of charged particles was about 50% of total particles on the basis of number concentrations. There was no difference in the number concentrations as a function of size between positively and negatively charged particles.

           

16aB-4 

Oxidation of dilute Trichloroethylene by using Barrier Discharge Process combined with Manganese Dioxide

University of Tokyo

 SangBo Han and Tetsuji Oda     

In order to oxidize into small molecules of COx in the decomposition of dilute trichloroethylene, the barrier discharge process was studied experimentally. It was carried out by arranging catalyst of manganese dioxides at the downstream of plasma reactor. Decomposition efficiency was improved about 99% at the specific energy of 40J/L with passing through manganese dioxide and 98% of COx yield (CO and CO2) was attained at about 400J/L. In addition, this barrier discharge process was suppressed the generation of NOx (NO and NO2). This process is considered as very desirable way to increase decomposition efficiency and oxidize into COx along with the decrease of energy consumption.　　　Keywords: trichloroethylene, barrier discharge, manganese dioxide

           

16aB-5 

Decomposition Characteristics of VOCs by a Dielectric Barrier Discharge     

＊Institute of Fluid Science, Tohoku University，＊＊Graduate School of Engineering, Tohoku University (Presently, IBM Japan, Ltd.)       

Takehiko SATO＊, Makoto KAMBE＊＊ and Hideya NISHIYAMA＊

1. Experimental and numerical analyses have been adopted to clarify the key radical of the methanol decomposition process.

2. In experimental analysis, it is clarified that the DBD system decompose the methanol, ethanol and styrene completely below 50 ppm at discharge conditions as V = 16 kVpp and f = 100 Hz.

3. In numerical analysis, it is clarified that OH is an important radical to decompose the methanol. "    

 

16aB-6 

Optimization of Plasma-Driven Catalysis for the Decomposition of Benzene　Using Ag/TiO2 Catalyst  

National Institute of Advanced Industiral Science　andTechnolgoy(AIST)*， Dong-A University**        

Hyun-Ha KIM, Jeong-Uk Park, Seung-Min Oh, Kum-Chan Choi, Atsushi OGATA, Shigeru FUTAMURA 

Decomposition of benzene was investigated using plasma-driven catalyst (PDC) reactor packed with Ag/TiO2 catalyst. The influence of reaction temperature　on the benzene decomposition and the yields of reaction products indicated that the formation/decomposition of formic acid (HCOOH) played an important role in the benzene decomposition using the PDC reactor. The presence of water vapor decreased the decomposition of benzene in the PDC reactor. Water vapor had no effect on the COx (CO+CO2) selectivities. In contrast to the conventional plasma reactors (dielectric-barrier discharge and BaTiO3 pellet packed plasma reactor), the PDC reactor showed extraordinary dependence to the oxygen partial pressure. Decomposition efficiency of benzene increased with increasing oxygen partial pressure, while no influence with the DBD reactor and the BaTiO3 pellet packed plasma reactor above 20%. Based on this highly oxygen partial pressure-dependent behavior of the PDC reactor, oxygen plasma was investigated as a method to regenerate adsorbent/catalyst.          

 

16aB-7 

Oxidation of Carbon Monoxide by Using A Barrier Discharge

*Department of Electronic Engineering, University of Tokyo　**Midori Anzen.

Tetsuji Oda , Taisuke Murata, Koichi Ono, SangBo Han, Tomoyuki Saito       

Carbon monoxide is very poisonous gas for a living being but is easily produced in many human activities.   Examples are human smoking and firing in insufficient oxygen condition.  One simple method of nonpoisonization of carbon monoxide is oxidation.  Carbon monoxide can be oxidized to carbon dioxide which causes green house effect but not so harmful directly for us.   Barrier discharge should be a good oxidation process of carbon monoxide but experimental results suggest the oxidation is very weak.  At the best condition combined with manganese oxide, half carbon monoxide was oxidized to carbon dioxide.  

 

16aB-8 

Characteristics of Precipitation Efficiency and Gas Velocity for Electrostatic Precipitator of Special Structure（Part3）  

Fukui University of Technology    

Ayumu Iijima    

On the 2003 Annual Meating of this Institute, the auther reported the charactristics of precipitation efficiency and gas velocity for the electrostatic precipitator of special structure (part 2). It is investigated on the collection efficiency that made by the comparison between the electrostatic precipitator of single type and the proposed structure. As a result, it is found that by comparing with the single stage type, the proposed structure obtained good collection efficiency. Application of the proposed structure is expected to lead to a reduction in the size of precipitators.

           

16pS-1

Some Basic Plasma Technoloties for Application　Tohoku Univ.       

Noriyoshi Sato

The author has been interested in basic plasma technologies necessary for next-stage plasma application. Here some of related plasma technologies proposed up to now are presented, which are concerned with plasma production, electron-temperature control, and collection and removal of dusty fine particles. Most of them have already been well established for plasma application. Drastic results based on those plasma technologies are also described.

 

16pC-1             

Yamagata University

                       

16pC-2 

Droplet actuation based on single-phase electrostatic excitation       

＊:Dept. of Mechanical Eng. The Univ. of Tokyo,  ＊＊: Shimadzu corp.

Masahide Gunji(＊), Hiroaki Nakanishi(＊＊), Masao Washizu(＊)   

A new concept of electrostatic droplet actuation based on field-induced deformation of the droplet is presented in this paper. The device consists of a diagonal fishbone-shaped electrode array with a hydrophobic coating. When energized with an AC voltage, a droplet dispensed on the electrode undergoes a periodical motion of flattening and restoring the spherical shape, and because of the geometrical asymmetry of the electrodes, its center of mass is shifted bit by bit in each cycle. The actuation speed as high as 2.4 cm/s is achieved for a 1 l-droplet on a 240 m-pitch electrode array with 50 Hz, 50 Vrms excitation. Droplet sorting and mixing are also demonstrated by bifurcating and merging electrode arrays. The method only requires a pair of planar electrodes that can be fabricated by a single-mask process, and a single-phase power supply, leading to a simple and low-cost droplet-based micro-chemical system

 

16pC-3

Stability of Charged Emulsion in Water

Graduate School of Engineering, Hokkaido University

Tsuneki Ichikawa and Yoji Nakajima

The energy barrier preventing the coalescence of two charged emulsion droplets in water has been theoretically obtained in the framework of the DLVO theory in which the rearrangement of surface charges during the approach of the droplets is taken into account.

 

16pC-4 

Properties of Droplet Formation using a Novel Capillary with an　External Electrode

*Hamamatsu Photonics K.K., **Toyohashi University of Technology   Osamu Yogi*,**、Tomonori Kawakami*、Akira Mizuno**   

A capillary with an external electrode for cone-jet mode of electrospray has been developed  to spot a droplet  accurately on a substrate surface. The external electrode is made by gold deposition around tip of a glass capillary. The electrospray was made  by applying a positive pulsed dc voltage to the solution in the capillary. Using a positive bias voltage to the external electrode, the meniscus of the solution at the  tip  deformed  to  be more sharp, and center of the meniscus was prolonged. This deformation stabilized the trajectory of the jet from the meniscus called Taylor cone at the tip. From the experimental results, accuracy of positioning of the droplet  having  0.3  pL  volume was improved with the standard deviation of 1.1micrometers, from  that  of  2.5  micrometers for conventional capillary without the external electrode.

 

16pC-5 

High sensitive detection of Escherichia coli by impedance measurement using

Graduate School of Information Science and Electrical　Engineering, Kyushu University          

Tetsuji HATANO, Junya SUEHIRO, Masanori HARA         

This paper describes a high sensitive detection method of micro-sized　bacteria using a dielectrophoretic impedance measurement method assisted by　electropermeabilization. The authors have previously proposed a bacteria　detection technique called DEPIM (dielectrophoretic impedance measurement)　method using positive dielectrophoretic force to capture bacteria in　suspension onto an interdigitated microelectrode array. In the present　study,  electropermeabilization (EP) was combined with DEPIM in order to　improve the sensitivity as a result of intracellular ion release through　damaged cell membrane (EPA-DEPIM). The EP pulse parameters were optimized so　that conductance increase caused by electrolytic ion release from metal　electrodes could be suppressed. This enabled a secure detection of　intracellular ions released from bacteria avoiding disturbance of　electrolytic contamination from metal ions. Consequently, the lower limit of　EPA-DEPIM sensitivity for Escherichia coli (E. coli) detection was improved　from 104 cells/mL to 102 cells/mL for 3 hours diagnosis time.

 

16pC-6 

Detection of Specific Sequences under a Fluorescence Microscope Using Homologous Recombination Protein

＊Department of Mechanical Engineering, The University of Tokyo,＊＊Genomic Sciences Center, RIKEN＊＊＊The Horizontal Medical Research Organization, Kyoto University＊＊＊＊School of Science and Engineering, Waseda University         

Yuji KIMURA*, Takashi KINEBUCHI**, Hiroyuki KABATA***, Hitoshi KURUMIZAKA**** and Masao WASHIZU*

Optical mapping is a powerful method to map target sequences on DNA and facilitates to order large insert clones covering a large DNA, such as the human genome. To expand applications of optical mapping, the RecA protein was utilized for locating sequences of interest. The RecA protein forms a functional complex with single-stranded DNA, binds to double-stranded DNA, and searches sequences on the DNA homologous to that of the single-stranded DNA. We combined sequence-probing function of RecA with a microelectrode system by which DNA is immobilized with a uniformly-stretched conformation of DNA molecules. This combination enabled us to visualize fluorescence-labeled DNA probes, which consisted of exonuclease-resected duplex DNA, bound along target DNA. From the analysis of the binding position of the DNA probes, we expect RecA can be used as a sequence-probing tool for optical mapping.

 

16pC-7 

Stretching and positioning of single stranded DNA as a template for molecular construction     

Department of Mechanical Engineering, The University of Tokyo       

Takuya Kobayashi, Masao Washizu

The high-specificity self-assembling nature of DNA makes the molecule a candidate for the template for the construction of molecular devices. In order to construct a functional device, the template must be positioned onto a predetermined site on a substrate to allow external connections, and the components must be properly aligned onto the template. A key factor is the high yield of binding, especially when the device consists of many components. Such high yield requires that the bases of the template DNA be exposed so that its counterpart can interact freely, and the template be stretched to avoid folding or coiling that hampers the interaction. For this purpose, we have developed a method, by which a single-stranded DNA is stretched and immobilized bridging over an electrode pair, with the molecular ends anchored while the middle part is left free to interact with foreign molecules. We expect that these stretch-and-positioned DNA with accessible base-pairs will lead to the high-yield molecular construction.

 

16pC-8 

Acquisition of DNA Fragments Using Laser Ablation

*Advance Co., ** BRAIN, ***The University of Tokyo, Department of Mechanical Engineering  

Osamu KUROSAWA*,**,*** and Masao WASHIZU***       

A novel method for the acquisition of DNA fragments from targeted position of DNA using laser ablation is presented in this paper. The developed device consists of two substrates facing each other, a) an ablation substrate, where an ablation layer, a DNA carrier layer, and a pair of electrodes are deposited onto a glass substrate, and b) a counter substrate. DNA first is stretched and aligned onto the ablation substrates by the electrostatic stretch-and-positioning method. When the ablation layer is irradiated with a focused laser, it explodes, and the DNA fragment together with a piece of carrier layer is blasted, to be recovered onto the counter substrate. The experimental demonstration is made with a spin-coated 10-200nm thickness silica layer as the carrier layer, and a 100nm thickness black pigment as the ablation layer. Using 1mJ pulsed YAG laser, acquisition onto the counter substrate of 1) a 1.7mm-diameter micro bead on 10 nm thickness carrier layer, 2) DNA adsorbed on a 8mm-diameter 200nm-thickness micro disc, are demonstrated. When the method is applied for the acquisition of fragments from stretch-and-positioned DNA on 10 nm thickness carrier layer, the ablation itself was successful, but no fragment was detected on the counter substrate. A possible interpretation for this is that the ablated particle was so small that it failed to reach to the counter substrate by inertia, especially when it is electrostatically charged during the ablation and pulled back to the ablation substrate. The use of thicker micro-patterned substrate, by which the whole mass is ablated together, is expected to solve the problem, and our current effort is focused in this direction.

 

16pC-9 

recovery of DNA molecules from agarose gel using 　electrophoresis and electrolysis

Department of Ecological Engineering, Toyohashi University of Technology     

Jun Komatsu, Kazunori Takashima, Shinji Katsura, Akira Mizuno   

A manipulation technique of single-DNA molecule has been studied for genome analysis and observation of biological reactions at a single-molecule level. A manipulation of DNA molecules is difficult because long DNA molecules are very fragile in a solution. Especially, longer DNA molecules easily undergo fragmentation by convections of the solution. Although longer DNA molecules such as chromosomal DNA molecules are usually embedded in an agarose gel, called "gel-plug", to avoid such fragmentation, it is hard to handle the DNA molecules for biological experiments in a gel-plug. We proposed a recovery method of DNA molecules to a solution accompanied by a coil-globule transition. This method was based on electrophoresis and supplementation of cations which is necessary to globule-phase transition by electrolysis of aluminum electrodes.

 

16pC-10           

Development of Dielectrophoretic Filter for Viable-Nonviable Cell Separation

*Faculty of Engineering, Gunma University, **Masuda Research, Inc., ***Textile Research Institute of Gunma    

Masaru HAKODA*, Yoshikazu WAKIZAKA*, Shinichi MII**, Nobuyoshi KITAJIMA***, Naohiro SHIRAGAMI* 

In the large-scale cultivation of cells in a bioreactor, nonviable cells increase as time progresses. However, it is difficult to separate only the nonviable cells from the bioreactor. It is possible to discharge only the nonviable cells using a dielectrophoretic (DEP) filter; however, the separation efficiency is very low. In this paper, the separation efficiency of the novel DEP filter was examined. First, the electrical difference between viable cell and nonviable cell was clarified according to the single shell model. Using the wire-wire electrode was used as a model electrode of DEP-filter, the critical applied voltage which can be retained polystyrene standard particles by negative-DEP force in flow field was examined. The experimental value of the retention of particles followed the value of critical applied voltage deduced from relational equation of the ∇E2 and the dielectrophoretic velocity. Furthermore, the particles were separated using the cross-flow DEP-filter, and operating conditions such as applied voltage and flow velocity were examined. The operating condition for retaining particles from the experimental value of the dielectrophoretic velocity was clarified.

 

16pC-11

Gunma　Univ.   

Toshiko KAI, Takayuki OSHIMA, Masayuki SATO

 

16aC-1 

Soot Incineration of Diesel Engine Exhaust Using Nonequilibrium Plasma     

Osaka Prefecture University        

Masaaki OKUBO, Naoki Arita, Tomoyuki KUROKI and Toshiaki YAMAMOTO          

In recent years, the air pollution and the influence to human of NOx and PM from diesel engine exhaust gas become severe problems. More effective post-processing technology is desired on PM, such as carbon soots. In the present study, a regeneration of DPF was performed using the low temperature atmospheric pressure nonequilibrium plasma. In the experiment with a diesel engine, the regeneration of DPF could be confirmed, and the regeneration temperature could be decreased from 600℃ to 300℃.

           

16aC-2 

CO2 Reforming of Hydrocarbons with Nonthermal Plasma  

National Institute of Advanced Industrial Science and Technology     

Shigeru FUTAMURA and Annadurai GURUSAMY

CO2 reforming of methane, propane, and neopentane was investigated with a ferroelectric packed-bed reactor in N2 at different temperatures. No chemical interaction was observed between these hydrocarbons and CO2 in nonthermal plasma, and their conversions decreased with an increase in the counterpart hydrocarbon or CO2. H2 yield also decreased with an increase in CO2 concentration.  CO was formed both from CO2 and CH4, and its yield decreased with an increase in CH4 concentration. The molar ratio of H2 to CO depended on substrate hydrocarbon and reaction temperature, and decreased with increases in CO2 concentration and reactor energy density.  The reactivity of the hydrocarbon decreased in the order: propane > neopentane > methane.  With an increase in reaction temperature, hydrocarbon conversion and H2 yield increased.  Reaction temperature controls the subsequent and thermal processes of secondary decomposition of hydrocarbon and product formation, which are induced by radicals generated in situ         

 

16aC-3 

Fabrication and Application of Carbon Nanotube-based Gas　Sensor Using Dielectrophoresis 

Graduate School of Information Science and Electrical　Engineering, Kyushu University

Guangbin ZHOU, Hiroshi IMAKIIRE,Junya SUEHIRO and Masanori　HARA           

Carbon nanotubes (CNTs) have attracted much attention as a new class of　electronic materials because of their diameter of the order of nanometers　and their structurally sensitive electronic properties. In order to develop　an electronic device composed of CNTs, it is necessary to accurately　manipulate them to form a patterned array. In this study, a new fabrication　method of a gas sensor composed of multi-wall carbon nanotubes (MWCNTs)　using dielectrophoresis (DEP) was described. MWCNTs dispersed in ethanol　were trapped and enriched in an interdigitated microelectrode gap under　action of positive DEP force that drove MWCNTs to higher electric field　region. During trapping MWCNTs, the electrode impedance varied as the number　of MWCNTs bridging the electrode gap increased. After the DEP process, the　ethanol was evaporated and the microelectrode retaining the MWCNTs was　exposed to ammonia (NH3) or nitrogen dioxide (NO2) while the electrode　conductance was monitored. It was found that the electrode conductance was　altered by ppm-levels of NH3 as well as by sub-ppm level NO2 at room　temperature.

           

16aC-4 

Dielectrophoretic Fabrication of Carbon Nanotube-based NO2

Sensor and Sensitivity Control　Graduate School of Information Science and Electrical　Engineering, Kyushu University

Hiroshi IMAKIIRE, Guangbin ZHOU, Junya SUEHIRO and Masanori　HARA           

In our previous studies, it was demonstrated an electrokinetic fabrication　method of a carbon nanotube (CNT) gas sensor using dielectrophoresis. One　advantage of this method was that one could quantify the amount of trapped　CNTs on a real time basis by monitoring electrical impedance of the sensor　(dielectrophoretic impedance measurement, DEPIM). In the present study, we　extended the DEPIM technique and  controlled the amount of trapped CNTs.　This realized a production of CNT gas sensors with identical electrical　properties such as initial conductance. The gas sensor response to ppm-level　nitrogen dioxide (NO2) gas was investigated with various values of the　initial conductance. It was found that relative conductance change of the　CNT gas sensor after NO2 exposure increased almost proportionally with the　initial conductance for a constant NO2 concentration. This enabled to define　intrinsic sensitivity of CNT sensors by normalization. It was found that a　single-wall CNT gas sensor had higher normalized sensitivity than a　multi-wall CNT sensor.          

 

16aC-5 

Water Vapor Desorption and Adsorbent Regeneration Using Nonthermal Plasma

Department of Energy Systems Engineering, Osaka Prefecture University

Toshiaki YAMAMOTO, Goichi TANIOKA, Tomoyuki KUROKI and Masaaki OKUBO   

The dehumidification from a dehumidifier or an air conditioner was employed to achieve a comfortable and desirable indoor environment. Water vapor adsorbed on adsorbent needs to be regenerated when the water vapor exceeds the adsorption capacity. The conventional process for adsorbent regeneration or moisture desorption uses the heat by means of the heater. In the present study, the water vapor desorption from the adsorbent was investigated by using the nonthermal plasma for possible replacement of the electric heater. As a result, the water vapor desorption rate showed superior characteristics in term of energy efficiency. i.e. desorption per unit energy is significantly higher. At the same time, the gradient of water vapor desorption (desorption rate) is significantly higher or quick desorption can be achieved, which leads to more controllable and flexible air conditioning system.

 

16aC-6 

Effective Combination Methods for Useful Zeolites and Nonthermal Plasma Hybrid System in Toluene Decomposition    

National Institute of Advanced Industrial Science and Technology      S

eung-Min OH*, Hyun-Ha KIM*, Hisahiro EINAGA*, Atsushi OGATA*, Shigeru FUTAMURA*, and Dong-Wha PARK**    

Toluene was decomposed in a surface discharge plasma reactor and the combination effect of zeolite in the plasma reactor was studied. The reactor configuration and the adsorption capacity of zeolite for toluene influenced on the decomposition efficiency and product compositions. Product gas consisted of CO2, CO and HCOOH including some intermediates, which decomposed to COx in a temperature-programm ed desorption (TPD) and oxidation (TPO) reactor. The synergistic effect of zeolite was attributed to toluene adsorption and followed by oxidation on the zeolite with O3 derived from the plasma region. Adsorbed toluene on the zeolite was not properly decomposed in the head of plasma, while it was easily decomposed in the tail of plasma because oxygen species generated from plasma enhanced the toluene oxidation. With the increase of the decomposition efficiency, O3 concentration in the product gases was significantly reduced.           

 

16aC-7 

Surface Oxidation Process using an electron free negative ion generator         

National Institute of Advance Industrial Science and Technology (AIST)        

Masateru NISHIOKA

Strong, high purity and sustainable atomic oxygen radical anion (O?)　emission was observed from a synthesized microporous crystal 12CaO?　7Al2O3 (named C12A7) surface. The O- emission from the C12A7 has been applied to a surface oxidation treatment. A silicon wafer was used as　tested sample. In spite of low sample temperature (less than 350oC ) and high vacuum condition (less than 10-4Pa), the Si has been reacted to　SiO2 by O- irradiation. The surface roughness of O- oxidation Si was observed by AFM, there was not found significant difference between　thermal oxidation samples.        

 

16aC-8 

Numerical Simulation of CF4 Decomposition Using Low Pressure RF Plasma

Department of Energy Systems Engineering, Osaka Prefecture University      

Tomoyuki KUROKI, Shingo TANAKA, Masaaki OKUBO and Toshiaki YAMAMOTO   

Among perfluorocompounds (PFCs), we focused on CF4 used in semiconductor manufacturing process which was considered as one of the most difficult to decompose gas. We have been investigated the decomposition of CF4 using the inductively coupled plasma (ICP) reactor with RF power supply. This technology was confirmed to achieve a high efficiency and more economical system in comparison with the conventional system. Numerical simulation was carried out to obtain gas temperature, electron temperature and electron number density to cope with CF4 decomposition in the ICP reactor.

 

16pA-1

Characteristics of ""Elekiter"" (Electrostatic Generatior Restored Based on ""Erekiteru Zensho"" (Treatise on Electrostatic Generators)"    

Tottori　Ｕｎｉｖ．        

Ryo Nishimura, Katsumi Nishimori, Naganori Ishihara      

In 1770, Gennai Hiraga, a member of the Takamatsu clan born in Shidoura, Sanuki, Okawa-gun (a county of  Kagawa Prefecture) was given a broken machine called "Elekiter" which could generate static electricity by friction, belonging to a Dutch translator. He repaired the generator in 1776.  The Elekiter is believed to be the oldest electrical machine created in Japan.  In 1814, Tachu Kasamine described an inner structure and an example of the dimensions of the Elekiter.  In this research, aiming to investigate the characteristics of an Elekiter at that time, we restored an Elekiter referring to Tachu's discription without using synthetic resins.  The Elekiter was restored by using wood, metals, Japanese paper, silica glass and Japanese lacquer.  We measured the basic characteristics of the Elekiter.  The results showed that the generated potential was up to about 7 kV and the electrostatic voltage in the Leiden jar of the Elekiter decayed with the time constant depending on the generated voltage. 

 

16pA-2 

Frictional 　Electrification and Corona Electrification of 　Fibers   

Faculty of Textile Science and Technology, Shinshu University          

Masamichi NISHIZAWA, Isao NAKAMURA and Keiji OHARA        

An apparatus was constructed for simultaneous measurements of frictional electrification and corona electrification of filaments or fibers, and for estimating the electrification properties of fabrics from the electrification properties of fibers. As a preliminary experiment, nylon string was used, which was rubbed by PVC od. Nylon string was electrified positively as usually observed in triboelectric series of polymers. The magnitude of electrification voltage per unit length of strings was larger in the case of corona-electrification. As a result of analysis of variance, it was clear that the influence of the speed of fiber transfer on the  observed electrification voltage was effective.wever, the normal load has no effect on the electrification of nylon fiber.

 

16pA-3 

                                   

16pA-4

Tiny droplet formation on PDMS sheet by AC high electric field        

Department of Ecological Engineering, Toyohashi University of Technology     

Michihiko Nakano, Kazunori Takashima, Shinji Katsura, Akira Mizuno        

Small water droplets in oil were produced on dielectric film by AC high voltage. Electrodes of tungsten wire and aluminum tapes were covered with PDMS dielectric sheet. Water in oil emulsion was placed on PDMS sheet and AC high voltage was applied. When 5kVp was applied to the wire electrodes, large water droplets in oil were broken up to many tiny droplets, while they were moved toward to wire electrode due to dieletrophoretic force when the applied voltage below 3kVp. The size of the tiny droplets was approximately less than 10 m. After breaking up of water droplets, remaining droplets were placed in polygonal form under AC high electric field, which were not only pearl-chain but also triangle and square form.

 

16pA-5

The ion generation in the collision of the water jet

Department of Electrical and Electronic Engineering, Kanagawa Institute of Technology           

Hirofumi SHIMOKAWA  

It is known that the charged fog arises in the circumference of the water jet, when the water is ejected from the nozzle. Generation rate of the ion increases by the induction field. This report examined the ion which arose in the collision of the water. Next fact clarified as the result. (1)The reversely-polarized electrification fog arises on the polarity of the jet. (2)The electrification fog increases, as the impact angle increases, and as the impact speed increases. (3)The generation rate of the electrification fog is greatly dependent on the resistivity of the water, and the resistivity in which the electrification fog is minimized exists. (4)This phenomenon arises, when the water jet collides in the layer in the water on the metal. (5)For the generation of the reversely-polarized electrification fog, it is considered to originate from division of image electric charge induced on the water surface or division of the polarization charge on water droplet.

 

16pA-6 

Thermally stimulated current spectra of polypropylene heat-treated at high　temperatures.    

Keio University, Science University of Tokyo

Kazuo Ikezaki, Yuji Murata         

Thermally stimulated current (TSC) spectra were observed for polypropylene heat-treated at high temperatures.  The peak position and the half width of the high temperature TSC band  were examined in detail: With increasing treatment temperature, the peak position increased and the band width decreased till the treatment temperature of 150-155 C.   When the treatment temperature was raised to 160 C, then the peak position and the band width of the high temperature TSC band changed to decrease and increase, respectively.   These TSC results were discussed from a viewpoint of crystalline transition from alpha 1 to alpha 2 for polypropylene.

 

16pA-7 

Observation of flow electrification in dielectric liquid flows over metal walls   

Department of Mechanical Engineering, Faculty of Engineering, Okayama University  

Satoshi TAKAHASHI, Seiichi WASHIO, Hitoshi FUJIHARA           

In this paper, flow electrification between several kinds of metals and two kinds of dielectric liquids were measured. The electric current collected from a mesh increases with the flow rate and varies with the metal at the same flow rate. These results show that electric charges generated by flow electrification depend on the velocity at which liquid passes over the solid wall and also on the liquid-solid combination. Moreover, the charged oil passes through a mesh were relaxed in a low velocity, but as the velocity increase, the electric charges on the mesh by the electrification increase to the value of passing no-charged oil through it.

 

16pA-8 

Evaluation of the velocity of streamer in N2-O2 and SF6-N2 gas mixtures through Numerical Simulation Technique of Streamer Development       

Department of Electrical Engineering, The University of Tokyo         

Takashi Mizobuchi, Hiroyuki Toyota, Akiko Kumada, Kunihiko Hidaka         

Because the modeling of discharge phenomena is too complicate to understand completely the mechanism, the two approaches of experimental and theoretical studies are neccessary. Although numerical simulations are very useful for the theoretical study, they could sometimes be unstable or take too much time. In this paper, the discharge, especially the streamer discharge, in the N2-O2 and SF6-N2 gas mixtures is investigated by using the numerical simulation method.

 

16pA-9 

Influence of gas contents on negative air ion generation by corona　discharge

*Mitsubishi Electric Co.，**Faculty of Engineering, Tokyo University，***National Institute of Advanced Industrial Science and Technology          

Koji OHTA*, Yasuhiro TANIMURA*, Masaki KUZUMOTO*, Shinobu USHIJIMA**, Masateru NISHIOKA***, Mitsuo YAMAMOTO** and Masayoshi  SADAKATA**        

Atmospheric negative air ions generated by corona discharge have been measured by atmospheric pressure ionized mass spectrometer (API-MS). Principal negative ions generated in ultra-pure air were O−, O2−, O3−, NO2−, NO3− ions. Adding water in the ultra-pure air, O2−・n(H2O), O3− ・n(H2O), NO2−・n(H2O), NO3−・n(H2O) ions were detected in addition to the ions which detected in case of ultra-pure air. Adding carbon dioxide in ultra-pure air, CO3− ions was detected. But concentration of CO3− ions was not influenced by the concentration of carbon dioxide. In case of adding 4000ppm water vapor with mixture gas of ultra pure air and carbon dioxide, concentration of CO3−・n(H2O) ions increased remarkably. It turned out that the role with water vapor was shown in formation of carbonic acid ions.

 

16pA-10

Design and trial production of the electrostatic field mill

Iwate University

Daishi HATANAKA, Shusuke TAKAHASI, Shoji KATO, Seiji MUKAIGAWA,Koichi TAKAKI, Tamiya FUJIWARA          

A mill type electric field meter has been constructed to measure the electric field change due to lightning discharge. Alternating voltage proportional to the field is produced by the mill consisted of two inductive electrodes and four rotary blades. The preliminary experiment was performed using a DC high voltage power supply. The results showed that the output voltage increased with applied electric field and rotary speed. The maximum sensitivity of electric field is about 50,000V/m without amplifier.

 

16pA-11           

Induction Charging of Droplets by Vibrating Orifice Aerosol Generator and Application to Electric Field Measurement     

*Hokkaido Inst. Techno., **Hokkaido Univ.

Takashi SATO*, Keiichi YAMAYA*, Yoji NAKAJIMA*         

A small parallel plane electrode is installed at the position of the outlet hole of the head cover of a vibrating orifice aerosol generator. A DC voltage is applied to it so as to induce electric charge on the tip of liquid jet ejected from the earthed micro orifice. The liquid jet breaks up to yield charged droplets. In the present experiment, the relationship between the droplet charge and the liquid concentration, and the effect of the length of liquid jet have been examined. The results are as follows;

(1)The amount of charge is independent of evaporation of volatile liquid.

(2)The induced charge increases with the length of liquid jet.

 We used high voltage insulated cable as a test piece for electric field measurement

 

16aE-1

A study on ESD induced magnetically instability of GMR head        

Hitachi Global Storage Technologies Japan, Ltd.    

Kouji Kataoka，Shoji Natori and Takayoshi Ohtsu            

ESD tester for GMR head (Giant magneto-resistive head) which has unique ESD waveform simulator, AC type QST (Quasi-Static Tester )  and Laser heat function was developed. In this paper, we studied the ESD damage of GMR head by the ESD waveform. Furthermore, we investigated the ESD induced magnetically instability phenomena of GMR head.

 

16aE-2 

Analysis of ESD Failure Mode in GMR Head by Using Spinstand     

*Hitachi, Ltd. **Hitachi Global Storage Technologies Co., Ltd

Takayuki ICHIHARA*, Takehiko HAMAGUCHI* and Takayoshi OHTSU**   

Ａ new magnetic failure mode caused by ESD current was investigated using a spin-stand with a pre-amplifier with a built-in ESD simulator circuit. This failure mode originates in Barkhausen noise from unexpected domain walls in the free layer of a giant magnetoresistive (GMR) head. According to a modified machine model (0 ohm, 50 pF), this failure occurs at around 0.5 V, i.e., a quarter of that at which a conventional pinned layer reversal failure occurs.

 

16aE-3 

Characterization of ESD Control Material 

Kureha Chemical Industry Co., Ltd.

Naomitsu NISIHATA, Tatsuya KAWASAKI, Yuuichi KOMATSU       

New ESD control materials, based on combining special carbon material developed for the purpose of ESD control with PEEK (Polyetheretherketone), have been developed and assessed. The surface resistivity of the special carbon with resistivity of 107 ohms/sq., filled with PEEK, remained in the range of 108 to 109 ohms/sq. regardless of the carbon content beyond each critical range. The surface resistivity was easily controlled at the specific levels required for ESD control materials by using the special carbon. The surface resistivity fluctuation on the injection-molded plate was very small. The suitable surface resistivity range of ESD protection was estimated in the range of 108 to 109 ohms/sq. by the results of static decay time analysis and peak current analysis on ESD.

 

16aE-4 

Electrostatic Discharge from GMR Head in Magnetic Recording Tape System 

Advanced Tape Storage Development, Recording Media Company, Sony Corporation   

Yutaka SODA* and Hiroaki ONO 

A small sensor of a GMR head for magnetic recording is easily affected by electrostatic discharge(ESD). It was investigated that the GMR head in a helical-scan tape drive could be used in certain conditions of the tape surface resistance and the cassette material. Using the charged tape model increasing the tape surface resistance was effective in reducing the discharge current when the charge on the tape run through the GMR head.

The tribo-charge on the cassette made by rubbing the surface could induce the charge on the ME tape in the cassette. Using antistatic material for the cassette the charge on the tape was decreased less than the volume of the charge which can damage the GMR head

 

16aE-5 

The establishment of non-operation ESD test and the study of its damage mechanism for HDD

Hitachi Global Storage Technologies Japan, Ltd. 2.5"/1.8"CC BU, 1st design Dept.      

Tomohisa Okada

Electro-Static Discharge test widely uses as an electrical/magnetical evaluation test of component level like Giant Magneto-Resistive heads, head amplifers and read-write channels and it's damage mechanism is studied. On the other hand, ESD test performs as a reliability test of systems like mobile PCs, desk top PCs and so on. In order to understand system level ESD test, it is important to understand complex components like Head Stack Assemblys and Hard Disk Drives. But ESD test against complex components doesn't perform well. In this paper,ESD test evaluation method for HDD as the complex component was proposed and HDD's damage mechanism by ESD was studied.

 

16aE-6 

Electric characterristics of fluoric resin coared film reducing delamination charging of galass for LCD    

Kaijo corpration 

Akio FUJIE

There are many stages to put glass everywhere. The glass is pushed up by lift-up pins after being put on the stage, and having been　processed for such as vacuum absorption/ cooling or testing. At this time, Delamination charging with electricity happens to glass. I heard information that an overcoat of fluororesin is effective to restrain this delamination charging with electricity. I will report the result of measuring electric characteristics of the thin films and searching for some factors concerned with the reduction of the delamination charging with electricity on the glass.

 

16aE-7 

ESD Protections for Advanced Semiconductor Devices         

OKI Electric Industry Co., Ltd　SiSC(Silicon Solution Company) LSI Desighn Division

Yasuhiro Fukuda

Rapidly semiconductor device is developping to more integrated, high speed and low power device. This development is led by the innovations in telecominucation techniques, such as the cellular phone which is called "Keitai",  and other mobile equipments or terminals. On the other hand, it is realized the very integrated, high speed and low power semiconductor device by using new transistor structures, such as salicide or SOI transistor structures and separated power block designs. But generally these new technologies is weak to ESD (Electrostatic Discharge). This paper report ESD failure mechanism and protection design method for advanced semiconductor devices such as SOI devices.

 

16pE-1 

Characteristics of the conductive and dissipative implements which guard extremely sensitive devices against electrostatic discharge −The preventive measurement methods based on the excessive mobile charge−  

ESD Technical Department / Fab Solutions, Inc.     

Kouichi Suzuki, Naganori Takezawa, Michio Sato   

Conductive and dissipative implements are used to guard extremely sensitive devices against electrostatic discharge. The implements involve tweezers, device trays, mats on workbenches, carrier boxes of wafers, suction nozzles, UV sheets, garments and so on. Based on the excessive mobile charge theory, we developed the new measurement methods of IV characteristics and nano transient currents. Evaluation of implements with these methods showed that implements which carbon molecules are mixed into are characterized by the linearity, the resistance, the surface potential and the breakdown. Also, the suitable resistance of the conductive implements could be derived from the criteria of the excessive mobile charge. At present, almost all the implements cannot guard the extremely sensitive devices against the charged device model (CDM) and the stray capacitance model (SCM) events. However, the above study will give a clue to improve ESD safe material.

 

16pE-2 

Effect of Air Jet Rate on Static Elimination Characteristic of the Spot Jet Air Ionizer with jet emitter    

The Polytechnic University          

Hisayo YOSHIOKA, Nami TSURUTA and Kazuo OKANO   

An AC corona discharge air ionizer is one of the most useful equipment to eliminate static  charge on electronic devices in assembly processes. The inner jet air ionizer, which has a pipe-shaped emitter  to flow air in it, was proposed to increase the static elimination velocity. The static elimination velocity was  measured as a function of the air jet rate from the emitter. The elimination velocity of the inner jet air ionizer  depended on the flow rate and was 40 times higher than that of the non-jet air ionizer, when the ionizer was  operated with the biasing voltage of AC 16.0 kVP-P, 1 kHz, and 4.0 L/min of air jet rate.

 

16pE-3 

The High Frequency Corona Discharge Type Ionizer Suitable for the Measure of ESD Control against ESD Sensitive Device          

SHISHIDO　ELECTROSTATIC,LTD        

Wataru SHIMIZU，Hidemi NAGATA, Kenkichi IZUMI       

High frequency corona discharge type ionizer shows the epoch-making characteristic that formed air ions can be transferred through the tube and the metal pipe. Positive and negative ions formed by high frequency corona discharge are mixed uniformly, so the electric attraction between the air ions and the grounded body is weakened and the neutralization rate of air ions on the wall of the body becomes lower. This ionizer gives the solution for ESD trouble in the local and detail position that is difficult to solute by means of the conventional ionizer. Also, it has the unique characteristic that the surface potential change for every slight unit time of the charged object placed in the air ion flow from this equipment can be held small, because positive and negative ions are generated once by 1/68000 seconds

 

16pE-4 

A Consideration about Ionizer Balance in HGA Process       

Quality Engineering Dept.,Wuxi ALPS Electronics Co.,Ltd. *Manufacturing Dept.2 Manufacturing Engineering Sect.2, ALPS Electric. Co.,Ltd., Magnetic Devices Division. **  

Sadao Kawata *, Takanori Nakajima **    

ESD robustness of GMR Head is decreasing along the increasing of areal   density.  Using ionizer is the one of the most popular way to prevent the   ESD damage. Ionizer balance in the HGA process is controlled less than 5V  by  using  CPM ( Charge Plate Monitor ), because it was reported that the  D-CDM ( Direct Charged Devices Model ) ESD robustness of 30Gb/in2 is less  than 5V. This value will continue decreasing from now on too. It is shown theoretically and experimentally in this study that the voltage of CPM is  very  different from the voltage on actual devices. It is understood from  this study that Ionizer is the Constant Charge Density Supplier. And the  voltage  on  actual  devices is defined by capacitance of that object. At  the  same  time,  we  got  the  formula which shows the voltage on actual  device  from  standard CPM. As result we got the following conclusion. It  is  no  use  controlling the Ionizer balance with the same voltage as the  voltage  of D-CDM robustness when suspension is grounded. And we can know  the real voltage value of actual devices.

 

16pE-5

Action for the electrical charge of Operator working on the Hard Disk Drive's Manufacturing Line

Advanced Technology Japan, HDI System Development       

Kazushi Tsuwako           

A GMR sensor is most sensitive part to ESD among the parts used in a hard disk drive. It's sensitivity is getting higher and higher year-by-year. Therefore GMR damage is main manufacturing yield detractor on the manufacturing line. It was found that most of all GMR sensor's ESD damage was occurred by the operator's electrical charge on our manufacturing process.

This paper introduces the activities to reduce the human body electrical charge of the operator working on the hard disk drive's manufacturing line. "

 

16pE-6             

Department of Electrical Engineering, Tokyo University of Science    

Takenori SAWAI, Takahiro YOSHIDA, Noriaki MASUI       

 

16pE-7

Effect of the Shape of Charged Metal on the Waveform of Discharge Current　Department of Electrical Engineering, Tokyo University of Science

Nobuhide KITAZUME and Noriaki MASUI           

By using hemispherical electrodes, the effects of the curvature of electrode on the short air gap discharge are investigated. Brass electrodes having different radii of curvature, r = 2.5 mm and 20 mm were used. Applied voltage is from +3 kV to +8 kV. Discharge occurs between high voltage electrode connected to the capacitor of 250 pF and the grounded electrode. Grounded electrode approaches the high voltage electrode at 0.4 mm/s and spark discharge is occurred. When the applied voltage is from +6 kV to +8 kV, peak current for r = 2.5 mm becomes lower than that for r = 20 mm. Peak current for both electrodes shows almost the same value, when the applied voltage is +3 kV.

 

17aB-1 

Improvement of Dielectric Barrier Discharge Type　Ozonizer by Electrode Shape

Iwate University

Masaki SHIMIZU, Shoji KATO, Seiji MUKAIGAWA, Koichi　TAKAKI, Tamiya FUJIWARA    

An effect of electrode shape on ozone generation in dielectricbarrier discharge reactor　is described in this article.　Three different shape electrodes were employed as ground electrodes.A plane electrode is 6 cm in width, and 20 cm in length.　A trench electrode has large number of knife-edge rails.　A multipoint electrode has large number of four-sided pyramid projections on the plane.　A high voltage plane electrode is covered with 0.5 mm thickness alumina layer worked as　dielectric barrier.　The experimental results show that the breakdown for the multipoint electrode occurs at　7.0 kVpp.　This value is lower than 8.4 kVpp that is breakdown voltage of the plane electrode.

 

17aB-2

Ozone Generation by Pulsed Power Generator using SOS Diodes       

Iwate University

Sadahide SAWADA, Shoji KATO, Seiji MUKAIGAWA, Koichi TAKAKI, Tamiya FUJIWARA    

Pulsed power generator using SOS (Semiconductor Opening Switches)  as a opening switches can make compact and lightweight and be driven   at high repetition rate.   We produced compact pulsed power generator using SOS diodes and  drove the co-axial type plasma reactor for ozone generation.  The co-axial cylinder plasma reactor consists of 1 mm diameter  tungsten wire and 19 mm i.d. copper tube with 30 cm length.  The gas mixture of N2:O2=9:1 was used as diesel engine exhaust gas.  The energy efficiency for ozone generation was obtained to 70 g/kWh  at 100 ppm in circuit at C=0.7 nF and L=2.5 μH.

 

17aB-3 

Observation of OH Radicals in Atmospheric Pressure Corona Discharge by Laser-Induced Fluorescence

* Department of Electrical and Electronic Engineering, Oita University　　** Institute of Fluid Flow Machinery, Polish Academy of Sciences　*** Department of Engineering Physics, McMaster University

Seiji Kanazawa*, Atsushi Kajiwara, Jun-ichi Kumagai*, Hiroto Tanaka*, Toshikazu OHKUBO*, Yukiharu NOMOTO*, Marek Kocik**，Jerzy Mizeraczyk**，Jen-Shih Chang***      

The planar LIF detection of the hydroxyl (OH) radicals was performed in a nozzle-to-plane electrode system having an electrode gap of 30mm during the steady-state positive streamer corona discharge at atmospheric pressure. For monitoring the ground-state OH radicals, OH ( X2П(v’’=0)→ A2Σ+(v’=1) ) transition at 282nm was used. Two-dimensional OH distribution in the DC corona discharge in air/H2O/Ar mixture was investigated. The obtained results showed that the ground-state OH radicals were observed in the filamentary part of the no branching streamer produced by Ar injection through the nozzle.

 

17aB-4 

Laser Induced Fluorescence Measurement of Atomic Oxygen Generated by a Pulse Barrier Discharge -Oxygen Concentration Effects-         

University of Tokyo、National Institute of Advanced Indstrial Science and Technology

Kei Takezawa、Ryo Ono、Tetsuji Oda      

Laser Induced Fluorescence(LIF) measuring system was applied to the observation of atomic oxygen generated in a positive pulse barrier discharge under a high oxygen concentration condition. The electrode configuration is a metal needle to a plate of glass mounted on a ground plate.Oxygen density generated by a discharge and its reduction rate, oxygen z-scale distribution was not related to background oxygen concentration.The reduction rate at very close to the needle electrode was faster than one at other points.

 

17aB-5

Characteristics of Para