2008 IEEE 35th International Conference on Plasma Science最新文献

{"title":"Electron-beam generated air plasma: Ozone and electron density measurements","authors":"R. Vidmar, K. Stalder","doi":"10.1109/PLASMA.2008.4590950","DOIUrl":"https://doi.org/10.1109/PLASMA.2008.4590950","url":null,"abstract":"A 100-keV electron beam is used to ionize air within a test cell in which the pressure is varied from 1 mT to 600 T. In these experiments, the electron beam is operated with a single pulse of 10 -ms duration at a current of 5.6 mA. The beam in injected into the tank through a 12.7-mum aluminum foil window that separates the electron source from the test cell. Byproducts of volumetric ionization and dissociation include plasma electrons, ozone produced by the rapid reaction of atomic oxygen with oxygen in the air, and excitation of the N2 Second Positive line at 337.1 nm. The N2 emissions were observed 2 cm from the foil window using a fiber optic system. Ozone was detected by optical absorption at 255 nm and electrons were detected by an rf phase measurement system operating at 10 GHz. The ozone and rf measurements were made on the test-cell midplane, 25 cm from the foil window. An air chemistry code1 is used to estimate ozone production and rf phase shift as a function of volumetric ionization rate which was subsequently compared with the experimental data. These measurements are discussed as well as an estimate of the power required to generate and sustain the plasma density.","PeriodicalId":6359,"journal":{"name":"2008 IEEE 35th International Conference on Plasma Science","volume":"59 1","pages":"1-1"},"PeriodicalIF":0.0,"publicationDate":"2008-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72817676","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ion-temperature and rotation-velocity profile measurements from a spatially resolving x-ray crystal spectrometer on the alcator C-Mod tokamak","authors":"K. Hill, M. Bitter, S. Scott, A. Ince-Cushman, J. Rice, M. Reinke, P. Beiersdorfer, M. Gu, S.G. Lee, C. Broennimann, E. Eikenberry","doi":"10.1109/PLASMA.2008.4591121","DOIUrl":"https://doi.org/10.1109/PLASMA.2008.4591121","url":null,"abstract":"In this paper, a new spatially resolving X-ray crystal spectrometer (XCS) capable of measuring continuous spatial profiles of high resolution spectra (lambda/dlambda > 6000) of He-like and H-like Ar Kalpha lines has been installed on the Alcator C-Mod tokamak. The spectrometer has an improved measurements on ion temperature (Ti), intrinsic rotation-velocity profiles (vphi) with excellent spatial (~1 cm) and temporal resolution, and on the atomic physics of highly charged ions.The data analysis techniques, (Ti) and (vphi) profile results, analysis of background resulting from fusion neutrons, and predictions of performance on the international tokamak ITER and other tokamaks is presented.","PeriodicalId":6359,"journal":{"name":"2008 IEEE 35th International Conference on Plasma Science","volume":"13 1","pages":"1-1"},"PeriodicalIF":0.0,"publicationDate":"2008-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72919395","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Research of operation features of electrode units of high-voltage plasma generators of alternating current, definition of the criteria influencing the electrode lifetime at plasma generator operation on steam","authors":"A. Surov, V. Spodobin, R. Ovchinnikov, S. A. Kuschev, S. Lukyanov, V. Shiryaev, V. Kuznetsov","doi":"10.1109/PLASMA.2008.4591115","DOIUrl":"https://doi.org/10.1109/PLASMA.2008.4591115","url":null,"abstract":"At a modern level of industrial development the problem of waste processing has assumed a new significance. New laws and more strict standards are imposed every year in the majority of countries. Large industrial companies and municipal structures in this situation are forced to invest significant founds in waste destruction. Each year the creation of environmentally friendly technologies of waste treatment gets the increasing investment appeal. Plasmachemical technology is the most perspective technology of waste recycling. It is based on high-temperature plasmachemical action and complete decomposition of utilized products by means of arc plasma with useful product (synthesis-gas) production, which is a mixture of hydrogen and carbon oxide and is a valuable power raw material. One of the requirements to electric arc plasma generators working in plasmachemical installations is a long lifetime of continuous operation. First of all time of continuous operation of the plasma generator is determined by lifetime of its electrode unit. Now it is perspective to use steam as a plasmaforming environment. The idea of steam use as a working body is often put forward as one of alternatives to air plasma. Water has high heat of steam formation successfully combining properties of plasmaforming substance and cooling heat-carrier. Steam is an ideal plasmaforming environment. It is ecological, explosion-proof and available working substance favorably influencing on the ecological conditions in examined gasification processes.The paper depicts the investigation results carried out at development of plasma generators using steam as a plasmaforming environment. Modern methods of manufacturing of electrode materials allow creation of composite materials of complex composition by introduction of more refractory material in a copper matrix. The noticeable increase in life time and decrease in the specific flow rate (wear) of electrode material gives prospect in the further researches and development of new kinds of materials, that at steam application as a working body creates a wide spectrum of use of these high-voltage plasma generators at gasification and pyrolysis plants.","PeriodicalId":6359,"journal":{"name":"2008 IEEE 35th International Conference on Plasma Science","volume":"182 1","pages":"1-1"},"PeriodicalIF":0.0,"publicationDate":"2008-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80317178","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Commissioning of L-band intense electron linac for industrial applications","authors":"S. Kim, H.R. Yang, M. Cho, W. Namkung, S. Jang, S.J. Kwon, Y. Son, S. Park, J. Oh","doi":"10.1109/PLASMA.2008.4590859","DOIUrl":"https://doi.org/10.1109/PLASMA.2008.4590859","url":null,"abstract":"An intense L-band electron linear accelerator is under construction at CESC (Cheorwon Electron-beam Service Center) for industrial applications. It is capable of producing 10-MeV electron beams with 30-kW average beam power. For high-power capability, we adopted 1.3 GHz, and the RF source is a 25-MW pulsed klystron with 60-kW average RF output power. The PFN-type modulator and the matched transformer provide 264-kV beam voltage with 230-A beam current to the klystron. The RF pulse length is 7 mus, and the repetition rate is 350 Hz. The thermionic E-gun generates 80-kV electron beams with pulsed 1.6 A. The pre-buncher, a single standing-wave cavity, is used before the bunching section, which is built-in with the regular accelerating section. The accelerating structure is a disk-loaded waveguide with a constant-impedance operated in the 2pi/3-mode. It is to be operated under the fully beam-loaded condition, where the beam power is maximum. The electron beams are accelerated within 6 mus since the traveling-wave filling time of the accelerating structure is almost 0.8 mus. In this paper, we present details of the accelerator system and commissioning results.","PeriodicalId":6359,"journal":{"name":"2008 IEEE 35th International Conference on Plasma Science","volume":"137 1","pages":"1-1"},"PeriodicalIF":0.0,"publicationDate":"2008-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81752629","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Particle in cell simulations of a Tom Martin diode","authors":"S. Vickers","doi":"10.1109/PLASMA.2008.4590854","DOIUrl":"https://doi.org/10.1109/PLASMA.2008.4590854","url":null,"abstract":"Summary form only given. The Tom Martin (TM) radiographic diode comprises of a cathode ball mounted on a stalk, separated by vacuum from a flat plate metal anode target. A 2D model of this configuration, as fielded on AWE pulsed power machines, has been created using the particle in cell (PiC) code, large scale plasma (LSP). Predicted outputs have been compared to measured diagnostics in the voltage range of 3 to 6.5 MV. Modelling the cathode ball as a space charge limited source of electrons, qualitative agreement between the predicted and measured impedance histories is found. The model output is shown to be highly dependent on the size of the cathode emission region, with a range in the predicted diode impedance of 100 Omega. Coupled with approximate analysis methods and large experimental uncertainties, this dependence results in a range of diode behaviours that are consistent with the measured data. In this model, ion creation and emission from the target surface is neglected based on experimental observations. This assumption is tested against LSP target surface temperature predictions and found to be consistent over the voltage range considered.","PeriodicalId":6359,"journal":{"name":"2008 IEEE 35th International Conference on Plasma Science","volume":"55 1","pages":"1-1"},"PeriodicalIF":0.0,"publicationDate":"2008-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82294976","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Time-resolved observation of laser-assisted discharge plasmas for EUV sources","authors":"S. Katsuki, N. Tomimaru, T. Sakugawa, H. Akiyama","doi":"10.1109/PLASMA.2008.4591185","DOIUrl":"https://doi.org/10.1109/PLASMA.2008.4591185","url":null,"abstract":"In this paper a birdcage discharge head with a plane tin cathode and a stainless steel ball anode was fabricated which enables us to access to the plasma easily. A pulsed laser light with a fluence of 1010 W/cm2 was irradiated at a tin cathode surface to deliver tin vapor to the 5 mm electrode gap, where the high voltage was applied. High density hot plasmas were produced by the electromagnetic compression and the ohmic heating owing to the pulsed high current (20 kA, 150 ns) after the gaseous breakdown. The plasma compression process depends on the delay time dt from the laser irradiation to the breakdown because the laser produced vapor expands quickly, resulting in the change of the gas distribution. The EUV emission intensity was maximum when dt was 300 ns, while the emission region was minimum. The breakdown did not occur for dt smaller than 280 ns because the gas density might not be sufficiently large for the breakdown. The time-resolved imaging of the EUV emission using a gated pinhole EUV camera showed that the hot plasma was produced at first near the laser spot at the cathode and migrated toward the anode quickly. The migration of the hot plasma results in the enlargement of EUV emission region, which is unfavorable for a light source. The observation implies two mechanisms for the migration; one is the pressure wave propagation, and, the other is the collisional ionization of tin ions with electrons accelerated by the induced electric field, which is on the order of 1 MV/cm.","PeriodicalId":6359,"journal":{"name":"2008 IEEE 35th International Conference on Plasma Science","volume":"23 1","pages":"1-1"},"PeriodicalIF":0.0,"publicationDate":"2008-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86933993","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhanced magnetic energy released in solid-state and plasma loads on a nanosecond pulse power generator","authors":"A. Chuvatin, V. Kantsyrev, A. Astanovitskiy, R. Presura, A. Safronova, A. Esaulov, W. Cline, K. Williamson, I. Shrestha, M. Yilmaz, G. Osbome, T. Jarrett, B. LeGalloudec, N. Nalajala, L. Rudakov, M. Cuneo, T. Pointon, K. Mikkelson","doi":"10.1109/PLASMA.2008.4590967","DOIUrl":"https://doi.org/10.1109/PLASMA.2008.4590967","url":null,"abstract":"The requirements on lossless power transport through vacuum interface and MITL's limit from above the physical volume and hence inductance of the vacuum part of pulse power generators. This in turn limits the generator-to-load energy coupling and hence the magnetic energy available in vacuum loads used in high energy density physics research. We obtained on Zebra generator (1.9 Ohm, 1 MA, 100 ns) an enhanced load magnetic energy corresponding to the load current increase from the nominal 0.95 MA to 1.65 (plusmn0.05) MA. This improvement was achieved without changing the generator architecture, but through better generator-to-load energy coupling using the new Load Current Multipliers (LCM) technique. The average experimental load-to-generator current amplitude ratio in LCM with both a 7 nH constant-inductance load and with z-pinch loads was 1.7plusmn0.2. We report on new generator electrotechnical parameters with LCM and on characterization of the plasma dynamics and radiative properties of planar wire-array z-pinches at the achieved enhanced load magnetic energy level.","PeriodicalId":6359,"journal":{"name":"2008 IEEE 35th International Conference on Plasma Science","volume":"32 1","pages":"1-1"},"PeriodicalIF":0.0,"publicationDate":"2008-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87107622","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Stochastic heating in capacitively coupled plasmas","authors":"M. Bayrak, R. Brinkmann","doi":"10.1109/PLASMA.2008.4590832","DOIUrl":"https://doi.org/10.1109/PLASMA.2008.4590832","url":null,"abstract":"This paper presents a new numerical method for solving the reduced kinetic equation. This technique is based on the finite volume control method, which is often used in computational fluid dynamics. Additionally, in the boundary conditions the stochastic heating mechanism of the sheath is taken into account. Furthermore, the quasineutrality condition instead of the Poisson equation to solve the potential is used.","PeriodicalId":6359,"journal":{"name":"2008 IEEE 35th International Conference on Plasma Science","volume":"47 1","pages":"1-1"},"PeriodicalIF":0.0,"publicationDate":"2008-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88354616","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical simulations of explosive arc suppression used in fast fault current limiters","authors":"K. Niayesh, J. Jadidian, E. Hashemi, E. Agheb, A.A. Shaygani-Akmal","doi":"10.1109/PLASMA.2008.4590942","DOIUrl":"https://doi.org/10.1109/PLASMA.2008.4590942","url":null,"abstract":"Numerical simulations are presented for physical behavior of the explosive current interrupter system consisting of two parallel half tube-shaped conductors (bursting bridge). The magnetohydrodynamic approach, together with the detailed explosion equations for the expanding electrodes, is used to describe the behavior of explosive arc suppression. Bursting bridge conduct a 50Hz high current (up to 200kA) filled with high explosive charge. After tripping, the explosive charge is detonated, explodes the tube-shaped conductors (bursting bridge), separates the electrodes and suppresses the plasma flow in an extremely fast manner. Such configuration has been used recently as a fast current limiter in electrical distribution networks with very high short circuit current levels.","PeriodicalId":6359,"journal":{"name":"2008 IEEE 35th International Conference on Plasma Science","volume":"30 1","pages":"1-1"},"PeriodicalIF":0.0,"publicationDate":"2008-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88447343","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"DC operated atmospheric pressure air plasma jet for biomedical applications","authors":"J. Kolb, R. O. Price, M. Stacey, R. J. Swanson, A. Bowman, R. Chiavarini, K. Schoenbach","doi":"10.1109/PLASMA.2008.4591008","DOIUrl":"https://doi.org/10.1109/PLASMA.2008.4591008","url":null,"abstract":"We have previously presented a gas discharge assembly based on a microhollow cathode geometry which can be operated with a dc current at atmospheric pressure with ambient air1. By flowing air through the discharge channel at a rate of about 7 Ltr/min a 10-20-mm long plume is observed. The temperature in this expelled afterglow plasma reaches values that are close to room temperature at a distance of 5 mm from the discharge origin. Emission spectra show that atomic oxygen, hydroxyl ions and various nitrogen compounds are generated in the discharge and are driven out with the gas flow. The most prominent secondary discharge product, ozone, is detected in high concentrations. The low heavy-particle temperature allows us to use this exhaust stream on biological samples and tissues without thermal damage. The high levels of reactive species suggest an effective treatment for pathological skin conditions caused, in particular, by infectious agents. In the first experiments, we have successfully tested the efficacy of this afterglow plasma on Candida kefyr (a yeast), E.coli (bacteria), and a matching E.coli strain-specific virus, 0X174 (a bacteriophage). All pathogens investigated responded well to the treatment. In the yeast case, complete eradication of the organism in the treated area could be achieved with an exposure of 90 seconds at a distance of 5 mm. A 10-fold increase of exposure, to 900 seconds caused no observable damage to murine integument. The quantification of the response, and studies of possible mechanisms are underway.","PeriodicalId":6359,"journal":{"name":"2008 IEEE 35th International Conference on Plasma Science","volume":"29 1","pages":"1-1"},"PeriodicalIF":0.0,"publicationDate":"2008-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86474320","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}