Pub Date : 2013-06-16DOI: 10.1109/PLASMA.2013.6634876
J. Pasour, E. Wright, K. Nguyen, A. Balkcum, B. Levush
Summary form only given. A compact, 94-GHz extended interaction klystron (EIK) amplifier has been developed and tested. A peak power of over 6.6 kW has been measured at the output flange of the device (in air), corresponding to over 8 kW at the output cavity aperture (in vacuum). The observed output is in excellent agreement with 3-D PIC simulations. The EIK is driven by a 19-21 kV, 3.5-4 A sheet beam in a permanent magnet solenoid, with 99% of the beam current transmitted through a 0.4 × 5 mm × 2.6-cm-long beam tunnel. The circuit consists of three identical 5-gap cavities that can be tuned individually. Tuning the buncher cavity allows gain to be traded for peak power. A sample drive curve is shown below. This amplifier demonstrates the significant increase in power that can be achieved at a given operating voltage by substituting a sheet beam for the pencil beam used in conventional vacuum electronic amplifiers. It also validates the use of solenoidal focusing for high-perveance sheet beams. High-peak-power testing and the potential for high-average-power operation will be discussed.
{"title":"Demonstration of a high-power (>6 KW) W-band sheet beam extended interaction klystron (EIK)","authors":"J. Pasour, E. Wright, K. Nguyen, A. Balkcum, B. Levush","doi":"10.1109/PLASMA.2013.6634876","DOIUrl":"https://doi.org/10.1109/PLASMA.2013.6634876","url":null,"abstract":"Summary form only given. A compact, 94-GHz extended interaction klystron (EIK) amplifier has been developed and tested. A peak power of over 6.6 kW has been measured at the output flange of the device (in air), corresponding to over 8 kW at the output cavity aperture (in vacuum). The observed output is in excellent agreement with 3-D PIC simulations. The EIK is driven by a 19-21 kV, 3.5-4 A sheet beam in a permanent magnet solenoid, with 99% of the beam current transmitted through a 0.4 × 5 mm × 2.6-cm-long beam tunnel. The circuit consists of three identical 5-gap cavities that can be tuned individually. Tuning the buncher cavity allows gain to be traded for peak power. A sample drive curve is shown below. This amplifier demonstrates the significant increase in power that can be achieved at a given operating voltage by substituting a sheet beam for the pencil beam used in conventional vacuum electronic amplifiers. It also validates the use of solenoidal focusing for high-perveance sheet beams. High-peak-power testing and the potential for high-average-power operation will be discussed.","PeriodicalId":6313,"journal":{"name":"2013 Abstracts IEEE International Conference on Plasma Science (ICOPS)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74681058","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}
Pub Date : 2013-06-16DOI: 10.1142/S2010194514603305
N. Zavyalov, V. S. Gordeev, V. Punin, A. Grishin, G. A. Myskov, S. Nazarenko, E. Mikhailov, D. A. Kalashnikov, A. Kozachek, V. Pavlov, K. Strabykin, S. L. Glushkov, S. Puchagin, V. L. Mayornikova, R. Mayorov, M. A. Moiseevskikh
A multi-terawatt pulsed power facility ≪Gamma-1≫ is being developed in RFNC-VNIIEF. It is planned that facility will consist of 16 independent modules, each being capable of generating electric pulses with peak power up to 1.5 TW. The facility will be used for investigations in the field of radiation physics.
{"title":"High-current pulsed electron accelerator «Gamma-1» with output power up to 1.5 TW","authors":"N. Zavyalov, V. S. Gordeev, V. Punin, A. Grishin, G. A. Myskov, S. Nazarenko, E. Mikhailov, D. A. Kalashnikov, A. Kozachek, V. Pavlov, K. Strabykin, S. L. Glushkov, S. Puchagin, V. L. Mayornikova, R. Mayorov, M. A. Moiseevskikh","doi":"10.1142/S2010194514603305","DOIUrl":"https://doi.org/10.1142/S2010194514603305","url":null,"abstract":"A multi-terawatt pulsed power facility ≪Gamma-1≫ is being developed in RFNC-VNIIEF. It is planned that facility will consist of 16 independent modules, each being capable of generating electric pulses with peak power up to 1.5 TW. The facility will be used for investigations in the field of radiation physics.","PeriodicalId":6313,"journal":{"name":"2013 Abstracts IEEE International Conference on Plasma Science (ICOPS)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72767986","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}
Pub Date : 2013-06-16DOI: 10.1109/PLASMA.2013.6634933
B. Yee, J. Foster, B. Weatherford, E. Barnat
Summary form only given. Pulsed, nanosecond discharges (PNDs) are notable for their large volumes and nonthermal nature. The large volume is attractive for material processing and the nonthermal electron can be used to drive reactions with minimal gas or substrate heating. However, the stochasticity of such plasmas presents a challenge for simulations, while the short time scales and large fields limit experimental diagnostics. This has led to a degree of uncertainty in the electron energetics of PNDs, particularly when nonlocal electron effects become important. This uncertainty also inhibits the predictive capabilities for PNDs. This work examines the population kinetics of a helium PND, and uses them to infer conclusions about the electron energetics. Specifically, the absolute triplet metastable densities are measured with laser-absorption spectroscopy. These densities are used in combination with a global model of a helium plasma to predict plasma emissions. These emissions are compared with the measured plasma emissions. As this method assumes electron locality, the degree of agreement between the two should reflect the accuracy of this assumption. The results are discussed in the context of the electron energetics, and compared to preliminary results of PIC-MCC simulations.
{"title":"Electron energetics in a helium pulsed nanosecond discharge","authors":"B. Yee, J. Foster, B. Weatherford, E. Barnat","doi":"10.1109/PLASMA.2013.6634933","DOIUrl":"https://doi.org/10.1109/PLASMA.2013.6634933","url":null,"abstract":"Summary form only given. Pulsed, nanosecond discharges (PNDs) are notable for their large volumes and nonthermal nature. The large volume is attractive for material processing and the nonthermal electron can be used to drive reactions with minimal gas or substrate heating. However, the stochasticity of such plasmas presents a challenge for simulations, while the short time scales and large fields limit experimental diagnostics. This has led to a degree of uncertainty in the electron energetics of PNDs, particularly when nonlocal electron effects become important. This uncertainty also inhibits the predictive capabilities for PNDs. This work examines the population kinetics of a helium PND, and uses them to infer conclusions about the electron energetics. Specifically, the absolute triplet metastable densities are measured with laser-absorption spectroscopy. These densities are used in combination with a global model of a helium plasma to predict plasma emissions. These emissions are compared with the measured plasma emissions. As this method assumes electron locality, the degree of agreement between the two should reflect the accuracy of this assumption. The results are discussed in the context of the electron energetics, and compared to preliminary results of PIC-MCC simulations.","PeriodicalId":6313,"journal":{"name":"2013 Abstracts IEEE International Conference on Plasma Science (ICOPS)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72950675","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}
Pub Date : 2013-06-16DOI: 10.1109/PLASMA.2013.6634846
Ruonan Ma, B. Su, Ying Tian, Qian Zhang, Jing Fang, Jue Zhang, H. Feng, Yongdong Liang
Summary form only given. In previous studies, we have found that during atmospheric pressure cold plasma treatment, oxidative stress pathways are required for yeast cell response. In addition, overexpressions of anti-oxidant superoxide dismutase (SOD) genes can remarkably protective yeast cells from plasma injury. These results are in coincidence with other groups' findings with mammalian cells, thus encouraging us to explore more on the anti-oxidative responses in eukaryotic cells subjected to plasma treatment, which is valuable for guiding the safety and precautionary measures for potential plasma medicine applications in the near future. In this study, the live yeast cell derivative (LYCD) was obtained by yeast cells exposed to sub-lethal doses of plasma treatment. The characteristics of the LYCD induced by plasma were evaluated by analyzing the collaboration of three important anti-oxidative systems in eukaryotic cells, superoxide dismutase (SOD) system, catalase (CAT) system and glutathione (GSH) system. The SOD and CAT activities, as well as reduced GSH and oxidized GSH amount were tested by kits and compared among the strains. And other important compositions of LYCD were detected by mass spectrum (MS). In addition, LYCD of cells after UV or H2O2 are reported to be UV or H2O2 protective. We also looked into the effects of LYCD after plasma treatment by applying it to various types of cells subjected to plasma. Then Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) viabilities were measured by colony counting method, while Saccharomyces cerevisiae (S. cerevisiae), human breast cancer (MCF-7) and human embryonic skin fibroblasts (CCC-ESF-1) viabilities were assessed by XTT assay. The results indicated that the activities of SOD, CAT and the reduced GSH amount of LYCD increase linearly with plasma treatment time. More interestingly, those three important antioxidative substances extracted from yeast cell can act in accordance with each other. Furthermore, we observed that the LYCD induced by plasma can in turn effectively protect various types of cells from plasma damage. Detailed results will be discussed at the conference.
{"title":"Characterization of live yeast cell derivative (LYCD) induced by atmospheric pressure cold plasma and its protective effects on cells","authors":"Ruonan Ma, B. Su, Ying Tian, Qian Zhang, Jing Fang, Jue Zhang, H. Feng, Yongdong Liang","doi":"10.1109/PLASMA.2013.6634846","DOIUrl":"https://doi.org/10.1109/PLASMA.2013.6634846","url":null,"abstract":"Summary form only given. In previous studies, we have found that during atmospheric pressure cold plasma treatment, oxidative stress pathways are required for yeast cell response. In addition, overexpressions of anti-oxidant superoxide dismutase (SOD) genes can remarkably protective yeast cells from plasma injury. These results are in coincidence with other groups' findings with mammalian cells, thus encouraging us to explore more on the anti-oxidative responses in eukaryotic cells subjected to plasma treatment, which is valuable for guiding the safety and precautionary measures for potential plasma medicine applications in the near future. In this study, the live yeast cell derivative (LYCD) was obtained by yeast cells exposed to sub-lethal doses of plasma treatment. The characteristics of the LYCD induced by plasma were evaluated by analyzing the collaboration of three important anti-oxidative systems in eukaryotic cells, superoxide dismutase (SOD) system, catalase (CAT) system and glutathione (GSH) system. The SOD and CAT activities, as well as reduced GSH and oxidized GSH amount were tested by kits and compared among the strains. And other important compositions of LYCD were detected by mass spectrum (MS). In addition, LYCD of cells after UV or H2O2 are reported to be UV or H2O2 protective. We also looked into the effects of LYCD after plasma treatment by applying it to various types of cells subjected to plasma. Then Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) viabilities were measured by colony counting method, while Saccharomyces cerevisiae (S. cerevisiae), human breast cancer (MCF-7) and human embryonic skin fibroblasts (CCC-ESF-1) viabilities were assessed by XTT assay. The results indicated that the activities of SOD, CAT and the reduced GSH amount of LYCD increase linearly with plasma treatment time. More interestingly, those three important antioxidative substances extracted from yeast cell can act in accordance with each other. Furthermore, we observed that the LYCD induced by plasma can in turn effectively protect various types of cells from plasma damage. Detailed results will be discussed at the conference.","PeriodicalId":6313,"journal":{"name":"2013 Abstracts IEEE International Conference on Plasma Science (ICOPS)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73258061","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}
Pub Date : 2013-06-16DOI: 10.1109/PLASMA.2013.6635074
B. Huhman, J. Neri, D. Wetz
Summary form only given. The Materials Testing Facility (MTF) at the U.S. Naval Research Laboratory (NRL) is developing a battery-powered, rep-rate charger for a 60-kJ capacitor bank. The objective is to charge a 4800-μF capacitor to 5-kV in four seconds for a fifty shot burst. A bank of LiFePO4 batteries is used with a full H-bridge converter, a transformer, and a rectifier to transform the 500V battery voltage to 5-kV secondary voltage.
{"title":"Investigations into the use of an LLC converter for rep-rate capacitor charging systems","authors":"B. Huhman, J. Neri, D. Wetz","doi":"10.1109/PLASMA.2013.6635074","DOIUrl":"https://doi.org/10.1109/PLASMA.2013.6635074","url":null,"abstract":"Summary form only given. The Materials Testing Facility (MTF) at the U.S. Naval Research Laboratory (NRL) is developing a battery-powered, rep-rate charger for a 60-kJ capacitor bank. The objective is to charge a 4800-μF capacitor to 5-kV in four seconds for a fifty shot burst. A bank of LiFePO4 batteries is used with a full H-bridge converter, a transformer, and a rectifier to transform the 500V battery voltage to 5-kV secondary voltage.","PeriodicalId":6313,"journal":{"name":"2013 Abstracts IEEE International Conference on Plasma Science (ICOPS)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73687738","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}
Pub Date : 2013-06-16DOI: 10.1109/PLASMA.2013.6634773
V. Vdovin, V. Andreev, A. B. Vasil’ev, Yuriy K. Kalynov
Summary form only given. Results of measurements of electromagnetic pulses with 3 to 10 mcs duration at frequencies 0.55-0.87 THz by the thermoacoustic detector are presented. Operation of the detector is based on effect of acoustic signal generation when electromagnetic pulses are absorbed in the layered structure: radiotransparent substrate-absorber-immersion liquid. Thin metallic film of nanometer thickness sputtered onto the quartz substrate is used as an absorber. The transformation of electromagnetic radiation into acoustic pulse is performed in the film and in the liquid contacting with the film. Acoustic pulse is detected by the broadband acoustic transducer and registered with a digital oscilloscope. It is shown that for the pulse of microsecond duration the signal waveform detected by the thermoacoustic detector is completely matched to the derivative of a profile of terahertz pulse. When water and ethanol are used as immersion liquids the presence of additional film absorber is not compulsory because these liquids absorb effectively the electromagnetic radiation in frequency range 0.5-1 THz.
{"title":"Detection of powerful terahertz pulses with use of termoacoustic probe","authors":"V. Vdovin, V. Andreev, A. B. Vasil’ev, Yuriy K. Kalynov","doi":"10.1109/PLASMA.2013.6634773","DOIUrl":"https://doi.org/10.1109/PLASMA.2013.6634773","url":null,"abstract":"Summary form only given. Results of measurements of electromagnetic pulses with 3 to 10 mcs duration at frequencies 0.55-0.87 THz by the thermoacoustic detector are presented. Operation of the detector is based on effect of acoustic signal generation when electromagnetic pulses are absorbed in the layered structure: radiotransparent substrate-absorber-immersion liquid. Thin metallic film of nanometer thickness sputtered onto the quartz substrate is used as an absorber. The transformation of electromagnetic radiation into acoustic pulse is performed in the film and in the liquid contacting with the film. Acoustic pulse is detected by the broadband acoustic transducer and registered with a digital oscilloscope. It is shown that for the pulse of microsecond duration the signal waveform detected by the thermoacoustic detector is completely matched to the derivative of a profile of terahertz pulse. When water and ethanol are used as immersion liquids the presence of additional film absorber is not compulsory because these liquids absorb effectively the electromagnetic radiation in frequency range 0.5-1 THz.","PeriodicalId":6313,"journal":{"name":"2013 Abstracts IEEE International Conference on Plasma Science (ICOPS)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73688654","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}
Pub Date : 2013-06-16DOI: 10.1109/PLASMA.2013.6633283
V. R. Narayanan, J. Heberlein, Christian Ruempler
Summary form only given. Metallic vapor emanating from the electrodes and plastic vapor from wall ablation on or before current-zero in a low-voltage circuit breaker (LVCB) significantly affect the dielectric recovery characteristics of atmospheric pressure air in the contact gap after current-zero. When the net ionization coefficient becomes positive, dielectric breakdown is said to occur and the reduced electric field (E/N) of this occurrence is termed the critical reduced electric field ((E/N)crit) [1]. In this paper, we analyze the dielectric breakdown behavior for the case of copper being the electrode material and polyamide 6/6 (PA-66) being the plastic wall material. Firstly, the chemical composition is calculated by the minimization of Gibbs free energy and the results are compared for two different methodologies (denoted as M1 [2] and M2 [3], for convenience). Unlike M2, M1 includes the condensed species of copper and carbon (graphite) and it will be shown that below 3500 K, the two methods provide widely different composition results. Secondly, Boltzmann's EEDF equation is solved to obtain the generalized non-Maxwellian electron-energy distribution function (EEDF) [4], with the electron-impact collision cross-sections gathered from literature as input. Using the afore-mentioned inputs, (E/N)crit is calculated and plotted against temperature ranging between 300-6000 K, for different mass-fraction values of air, copper and PA-66. Additionally, it has been observed that the presence of vibrationally- and electronically-excited species enhances the dielectric breakdown by lowering (E/N)crit. This approach is part of an initial attempt towards addressing realistic chemical non-equilibrium conditions involving finite-rate kinetics in an LVCB after current-zero and the numerical results will subsequently be utilized for comparisons with available experimental data.
只提供摘要形式。低压断路器在零电流时或零电流前电极产生的金属蒸汽和壁面烧蚀产生的塑料蒸汽对零电流后接触间隙内常压空气的介电恢复特性有显著影响。当净电离系数变为正时，介质击穿发生，这种现象的约简电场(E/N)称为临界约简电场((E/N)临界)[1]。本文分析了以铜为电极材料，聚酰胺6/6 (PA-66)为塑料壁材时的介电击穿行为。首先，通过Gibbs自由能最小化法计算化学成分，并比较两种不同方法(为方便起见，分别记为M1[2]和M2[3])的计算结果。与M2不同，M1包含铜和碳(石墨)的凝聚态，并且将显示在3500k以下，两种方法提供的组成结果差异很大。其次，以文献收集的电子碰撞截面作为输入，求解Boltzmann的EEDF方程，得到广义非麦克斯韦电子能量分布函数(generalized nonmaxwell electron-energy distribution function, EEDF)[4]。使用上述输入，对空气、铜和PA-66的不同质量分数值，在300-6000 K的温度范围内计算并绘制(E/N)临界值。此外，已经观察到振动和电子激发物质的存在通过降低(E/N)临界值来增强介电击穿。该方法是解决零电流后LVCB中有限速率动力学的实际化学非平衡条件的初步尝试的一部分，数值结果随后将用于与现有实验数据进行比较。
{"title":"Chemical equilibrium composition of air-copper-PA66 mixtures and their effects on dielectric breakdown for low-voltage circuit breaker post-current-zero","authors":"V. R. Narayanan, J. Heberlein, Christian Ruempler","doi":"10.1109/PLASMA.2013.6633283","DOIUrl":"https://doi.org/10.1109/PLASMA.2013.6633283","url":null,"abstract":"Summary form only given. Metallic vapor emanating from the electrodes and plastic vapor from wall ablation on or before current-zero in a low-voltage circuit breaker (LVCB) significantly affect the dielectric recovery characteristics of atmospheric pressure air in the contact gap after current-zero. When the net ionization coefficient becomes positive, dielectric breakdown is said to occur and the reduced electric field (E/N) of this occurrence is termed the critical reduced electric field ((E/N)crit) [1]. In this paper, we analyze the dielectric breakdown behavior for the case of copper being the electrode material and polyamide 6/6 (PA-66) being the plastic wall material. Firstly, the chemical composition is calculated by the minimization of Gibbs free energy and the results are compared for two different methodologies (denoted as M1 [2] and M2 [3], for convenience). Unlike M2, M1 includes the condensed species of copper and carbon (graphite) and it will be shown that below 3500 K, the two methods provide widely different composition results. Secondly, Boltzmann's EEDF equation is solved to obtain the generalized non-Maxwellian electron-energy distribution function (EEDF) [4], with the electron-impact collision cross-sections gathered from literature as input. Using the afore-mentioned inputs, (E/N)crit is calculated and plotted against temperature ranging between 300-6000 K, for different mass-fraction values of air, copper and PA-66. Additionally, it has been observed that the presence of vibrationally- and electronically-excited species enhances the dielectric breakdown by lowering (E/N)crit. This approach is part of an initial attempt towards addressing realistic chemical non-equilibrium conditions involving finite-rate kinetics in an LVCB after current-zero and the numerical results will subsequently be utilized for comparisons with available experimental data.","PeriodicalId":6313,"journal":{"name":"2013 Abstracts IEEE International Conference on Plasma Science (ICOPS)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74223222","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}
Pub Date : 2013-06-16DOI: 10.1109/PLASMA.2013.6635051
K. Fricke, M. Polák, A. Quade, K. Weltmann, A. Schmidt-Bleker, J. Winter, S. Reuter, A. Vogelsang
Recently reported progress regarding thin film deposition under atmospheric pressure conditions led to increased interests for its application in optics, semiconductor production, automotive, or medical industry. Therefore, extensively research has been performed in the development of atmospheric pressure plasma sources for thin film deposition. Miniaturized non-thermal atmospheric pressure plasma jets represent a suitable tool for local surface coating and thus for the preparation of chemical micro-patterns. Consequently, investigations are of interest concerning the feasibility of plasma jets in surface engineering for customer-specific requirements. So far, two atmospheric pressure plasma jets with different geometries have been developed, which can be used for this purposes 1-2. In these set-ups, the supply of the precursor can be realized in different ways: I) the mixture of carrier gas and precursor is introduced into the main flow downstream the active discharge or II) by using a cap which was build to control and tailor the gas curtain which can diffuse into the effluent of the jet2-3. In the present paper, results are given of an experimental study on plasma enhanced chemical vapor deposition under atmospheric pressure conditions. Emphasis is given on depositing films which exhibit either hydrophilic (e.g. nitrogen-rich coatings) or hydrophobic surface properties (e.g. Teflon-like coatings). The chemical structure of these films, measured by X-ray photo electron spectroscopy, as well as their wettability will be shown and discussed. Deposition rates have been determined by weighing. Hence, by controlling the deposition conditions film growth rates of 6-43 nm s-1 have been obtained for fluorine-rich films, for example.
{"title":"Local deposition of plasma-polymerized films at atmospheric pressure","authors":"K. Fricke, M. Polák, A. Quade, K. Weltmann, A. Schmidt-Bleker, J. Winter, S. Reuter, A. Vogelsang","doi":"10.1109/PLASMA.2013.6635051","DOIUrl":"https://doi.org/10.1109/PLASMA.2013.6635051","url":null,"abstract":"Recently reported progress regarding thin film deposition under atmospheric pressure conditions led to increased interests for its application in optics, semiconductor production, automotive, or medical industry. Therefore, extensively research has been performed in the development of atmospheric pressure plasma sources for thin film deposition. Miniaturized non-thermal atmospheric pressure plasma jets represent a suitable tool for local surface coating and thus for the preparation of chemical micro-patterns. Consequently, investigations are of interest concerning the feasibility of plasma jets in surface engineering for customer-specific requirements. So far, two atmospheric pressure plasma jets with different geometries have been developed, which can be used for this purposes 1-2. In these set-ups, the supply of the precursor can be realized in different ways: I) the mixture of carrier gas and precursor is introduced into the main flow downstream the active discharge or II) by using a cap which was build to control and tailor the gas curtain which can diffuse into the effluent of the jet2-3. In the present paper, results are given of an experimental study on plasma enhanced chemical vapor deposition under atmospheric pressure conditions. Emphasis is given on depositing films which exhibit either hydrophilic (e.g. nitrogen-rich coatings) or hydrophobic surface properties (e.g. Teflon-like coatings). The chemical structure of these films, measured by X-ray photo electron spectroscopy, as well as their wettability will be shown and discussed. Deposition rates have been determined by weighing. Hence, by controlling the deposition conditions film growth rates of 6-43 nm s-1 have been obtained for fluorine-rich films, for example.","PeriodicalId":6313,"journal":{"name":"2013 Abstracts IEEE International Conference on Plasma Science (ICOPS)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74327660","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}
Pub Date : 2013-06-16DOI: 10.1109/PLASMA.2013.6633367
M. U. Siddiqui, N. Hershkowitz
Summary form only given. The classic Bohm's Criterion is valid only for unmagnetized, weakly-collisional plasmas. For magnetized plasmas where the magnetic field is obliquely incident to the boundary, Chodura and later Riemann, claimed that the presheath, accelerates ions to the sound speed along the magnetic field lines. After this an additional “magnetic presheath” must exist, which scales with the ion gyro radius, and accelerates the ions from the sound speed along the magnetic lines of force, to the sound speed perpendicular to the boundary. Riemann and Franklin claimed that both the presheath and magnetic presheath had a single structure. Previous experiments attempted to verify the presheath scale lengths by measuring plasma potential structures, however none actually measured ion flow velocity, and as such their presheath lengths were not properly defined. Kim et. al. found that in magnetized and collisional plasmas, the presheaths had two distinct potential structures, one that scaled with the ion collision length and on that scaled with the ion gyro radius, contrary to Riemann and Franklin's claims. In this work the authors investigate magnetic and collisional presheath scale lengths in an inductive Argon plasma, using laser-induced fluorescence to measure ion flow speed thus and define the presheath boundaries. The scale lengths and presheath potential structures are compared to theory presented by Chodura, Riemann and Franklin.
{"title":"Measurement of magnetized presheaths using laser-induced fluorescence in argon plasmas","authors":"M. U. Siddiqui, N. Hershkowitz","doi":"10.1109/PLASMA.2013.6633367","DOIUrl":"https://doi.org/10.1109/PLASMA.2013.6633367","url":null,"abstract":"Summary form only given. The classic Bohm's Criterion is valid only for unmagnetized, weakly-collisional plasmas. For magnetized plasmas where the magnetic field is obliquely incident to the boundary, Chodura and later Riemann, claimed that the presheath, accelerates ions to the sound speed along the magnetic field lines. After this an additional “magnetic presheath” must exist, which scales with the ion gyro radius, and accelerates the ions from the sound speed along the magnetic lines of force, to the sound speed perpendicular to the boundary. Riemann and Franklin claimed that both the presheath and magnetic presheath had a single structure. Previous experiments attempted to verify the presheath scale lengths by measuring plasma potential structures, however none actually measured ion flow velocity, and as such their presheath lengths were not properly defined. Kim et. al. found that in magnetized and collisional plasmas, the presheaths had two distinct potential structures, one that scaled with the ion collision length and on that scaled with the ion gyro radius, contrary to Riemann and Franklin's claims. In this work the authors investigate magnetic and collisional presheath scale lengths in an inductive Argon plasma, using laser-induced fluorescence to measure ion flow speed thus and define the presheath boundaries. The scale lengths and presheath potential structures are compared to theory presented by Chodura, Riemann and Franklin.","PeriodicalId":6313,"journal":{"name":"2013 Abstracts IEEE International Conference on Plasma Science (ICOPS)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72563525","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}
Pub Date : 2013-06-16DOI: 10.1109/PLASMA.2013.6633455
B. Shrestha, P. Novak, D. Wetz
Summary form only given. The desire and need to field more compact pulsed power systems continues to grow with each passing day for use in many different applications. In the past, many pulsed power systems have been developed which use rechargeable batteries for the source of their prime power. In the time since the development of most of those systems, the demand for portable electronics and the growing desire to field hybrid electric vehicles has provided researchers with the resources needed to drastically improve the lifetime, safety, energy density, and power density of rechargeable batteries to technology levels only previously dreamed of. Improvements in these properties enable the development of prime power sources for pulsed power systems that are much more efficient and compact than those previously implemented. In these applications, where size is critical, the batteries are required to source currents at rates much higher than they are designed for in a high frequency, pulsed mode of operation. It is unclear how this extreme mode of operation impacts the size of the prime power system as well as how the capacity of the batteries will degrade compared to when they are discharged at their rated current. To gain a better understanding of the impact, the University of Texas at Arlington (UTA) is conducting experiments in which high power cells are pulsed discharged at an elevated rate. In the experiments presented here, a 3 Ah, lithium-ion battery has been discharged at a 100C rate, 300 A, using a switching frequency of 10 kHz and 50% duty cycle. The cell is periodically cycled at its rated current and the capacity fade and impedance variations are being evaluated and compared against a second identical cell which is being cycled under rated conditions. The test conditions, results collected thus far, and an analysis of how new technologies improves the size and efficiency of the prime power source will be presented. The results obtained are used to develop the model for the cell which shows the change in ESR and capacity as the cycle continues.
{"title":"Evaluation of high power energy storage devices for use in compact pulsed power systems","authors":"B. Shrestha, P. Novak, D. Wetz","doi":"10.1109/PLASMA.2013.6633455","DOIUrl":"https://doi.org/10.1109/PLASMA.2013.6633455","url":null,"abstract":"Summary form only given. The desire and need to field more compact pulsed power systems continues to grow with each passing day for use in many different applications. In the past, many pulsed power systems have been developed which use rechargeable batteries for the source of their prime power. In the time since the development of most of those systems, the demand for portable electronics and the growing desire to field hybrid electric vehicles has provided researchers with the resources needed to drastically improve the lifetime, safety, energy density, and power density of rechargeable batteries to technology levels only previously dreamed of. Improvements in these properties enable the development of prime power sources for pulsed power systems that are much more efficient and compact than those previously implemented. In these applications, where size is critical, the batteries are required to source currents at rates much higher than they are designed for in a high frequency, pulsed mode of operation. It is unclear how this extreme mode of operation impacts the size of the prime power system as well as how the capacity of the batteries will degrade compared to when they are discharged at their rated current. To gain a better understanding of the impact, the University of Texas at Arlington (UTA) is conducting experiments in which high power cells are pulsed discharged at an elevated rate. In the experiments presented here, a 3 Ah, lithium-ion battery has been discharged at a 100C rate, 300 A, using a switching frequency of 10 kHz and 50% duty cycle. The cell is periodically cycled at its rated current and the capacity fade and impedance variations are being evaluated and compared against a second identical cell which is being cycled under rated conditions. The test conditions, results collected thus far, and an analysis of how new technologies improves the size and efficiency of the prime power source will be presented. The results obtained are used to develop the model for the cell which shows the change in ESR and capacity as the cycle continues.","PeriodicalId":6313,"journal":{"name":"2013 Abstracts IEEE International Conference on Plasma Science (ICOPS)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78728287","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}
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