Pub Date : 2011-02-21DOI: 10.1109/IVEC.2011.5747039
K. Ashok, V. Raju, S. Chandralingam, P. Sarah
Bismuth layer structure ferroelectrics (BLSFs) have attracted intensive investigation for the potential use in non volatile ferroelectric random access memory (FeRAM) and piezoelectric devices suitable at high temperature. Bismuth layere structured compounds with general formula of (Bi2O2)2+ (Am−1BmO3m+1)2− are firstly found by Aurivillius1–3. The structure of these compounds can be described as pseudo-pervoskite (Am−1BmO3m+1)2− slabs separated by (Bi2O2)2+ layeres along the crystallographic c-axis4. The 12-coordinated A site can be occupied by such cations as La3+, Bi3+, Ba2+, Sr2+, Pb2+, Ca2+, Na+, etc. While the octahedral-coordinated B site can be occupied by W6+, Nb5+, Ta5+, Ti4+, etc. Lanthanum substituted BiT (Bi4Ti4O12) known as BLT has been extensively investigated. With this substitution, BLT shows relatively large Pr, low synthesis temperature and good fatigue endurance which makes it a potential candidate for FeRAM application. So, lanthanum doping is an effective way to improve the ferroelectric and fatigue properties of Bi4Ti4O12. Lanthanum doped Bismuth layer structure ferroelectrics (BLSFs) ceramics SrBi4−xLa xTi4O15 (x=0, 0.025, 0.050, 0.075, 0.1) were prepared by solid state reaction method. X-Ray diffraction pattern showed that single phase was formed when x=0− 0.1. Morphological studies were carried out by SEM analysis. It was found that crystal lattice constant, dielectric and electrical properties of SBT ferroelectrics varied appreciably with amount of doping. Dielectric measurements in the frequency range 100Hz–1MHz were made using an impedance analyzer (Wayne Kerr 6500P) and the measurements were carried out from RT to 600°C. The ferroelectric hysteresis loop was traced at room temperature by a standard P-E loop tracer based on sawyer-tower circuit. The values of 2Pr and Ec for pure and lanthanum doped SBT are given in the following table.
{"title":"Dielectric and ferroelectric properties of lanthanum doped SrBi4Ti4O15 ferroelectric ceramics","authors":"K. Ashok, V. Raju, S. Chandralingam, P. Sarah","doi":"10.1109/IVEC.2011.5747039","DOIUrl":"https://doi.org/10.1109/IVEC.2011.5747039","url":null,"abstract":"Bismuth layer structure ferroelectrics (BLSFs) have attracted intensive investigation for the potential use in non volatile ferroelectric random access memory (FeRAM) and piezoelectric devices suitable at high temperature. Bismuth layere structured compounds with general formula of (Bi<inf>2</inf>O<inf>2</inf>)<sup>2+</sup> (A<inf>m−1</inf>B<inf>m</inf>O<inf>3m+1</inf>)<sup>2−</sup> are firstly found by Aurivillius<sup>1–3</sup>. The structure of these compounds can be described as pseudo-pervoskite (A<inf>m−1</inf>B<inf>m</inf>O<inf>3m+1</inf>)<sup>2−</sup> slabs separated by (Bi<inf>2</inf>O<inf>2</inf>)<sup>2+</sup> layeres along the crystallographic c-axis<sup>4</sup>. The 12-coordinated A site can be occupied by such cations as La<sup>3+</sup>, Bi<sup>3+</sup>, Ba<sup>2+</sup>, Sr<sup>2+</sup>, Pb<sup>2+</sup>, Ca<sup>2+</sup>, Na<sup>+</sup>, etc. While the octahedral-coordinated B site can be occupied by W<sup>6+</sup>, Nb<sup>5+</sup>, Ta<sup>5+</sup>, Ti<sup>4+</sup>, etc. Lanthanum substituted BiT (Bi<inf>4</inf>Ti<inf>4</inf>O<inf>12</inf>) known as BLT has been extensively investigated. With this substitution, BLT shows relatively large P<inf>r</inf>, low synthesis temperature and good fatigue endurance which makes it a potential candidate for FeRAM application. So, lanthanum doping is an effective way to improve the ferroelectric and fatigue properties of Bi<inf>4</inf>Ti<inf>4</inf>O<inf>12</inf>. Lanthanum doped Bismuth layer structure ferroelectrics (BLSFs) ceramics SrBi<inf>4−x</inf>La <inf>x</inf>Ti<inf>4</inf>O<inf>15</inf> (x=0, 0.025, 0.050, 0.075, 0.1) were prepared by solid state reaction method. X-Ray diffraction pattern showed that single phase was formed when x=0− 0.1. Morphological studies were carried out by SEM analysis. It was found that crystal lattice constant, dielectric and electrical properties of SBT ferroelectrics varied appreciably with amount of doping. Dielectric measurements in the frequency range 100Hz–1MHz were made using an impedance analyzer (Wayne Kerr 6500P) and the measurements were carried out from RT to 600°C. The ferroelectric hysteresis loop was traced at room temperature by a standard P-E loop tracer based on sawyer-tower circuit. The values of 2P<inf>r</inf> and E<inf>c</inf> for pure and lanthanum doped SBT are given in the following table.","PeriodicalId":106174,"journal":{"name":"2011 IEEE International Vacuum Electronics Conference (IVEC)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121853741","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 : 2011-02-21DOI: 10.1109/IVEC.2011.5746882
Jean Gastaud, E. Gerard, A. Laurent
In satellite systems, on-board repeaters are required to provide higher and higher levels of RF power. Specifically in Ka band, a substantial increase of RF power is requested in some applications like HDTV and internet to improve the available data rate. In order to respond to this demand, Thales Electron Devices (TED), with the support of CNES (French Space Agency), is developing a TWT (TH4816) which delivers 170W in Ka frequency band. This paper gives the main technical characteristics of the TH4816 design and the main performances over the total Ka frequency band from 17.3 to 21.2 GHz.
{"title":"170 W Ka-band TWT for space applications","authors":"Jean Gastaud, E. Gerard, A. Laurent","doi":"10.1109/IVEC.2011.5746882","DOIUrl":"https://doi.org/10.1109/IVEC.2011.5746882","url":null,"abstract":"In satellite systems, on-board repeaters are required to provide higher and higher levels of RF power. Specifically in Ka band, a substantial increase of RF power is requested in some applications like HDTV and internet to improve the available data rate. In order to respond to this demand, Thales Electron Devices (TED), with the support of CNES (French Space Agency), is developing a TWT (TH4816) which delivers 170W in Ka frequency band. This paper gives the main technical characteristics of the TH4816 design and the main performances over the total Ka frequency band from 17.3 to 21.2 GHz.","PeriodicalId":106174,"journal":{"name":"2011 IEEE International Vacuum Electronics Conference (IVEC)","volume":"106 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131353686","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 : 2011-02-21DOI: 10.1109/IVEC.2011.5747029
M. Zhang, Xiaoxia Wang, Jirun Luo, Qinglan Zhao
This paper introduces plasma-sprayed technique, mainly focusing on the improved emission properties of plasma-sprayed oxide cathode and some problems to be solved in the future.
本文介绍了等离子喷涂技术，重点介绍了等离子喷涂氧化物阴极发射性能的改善及今后需要解决的问题。
{"title":"Influence of plasma spraying on emission of oxide cathode","authors":"M. Zhang, Xiaoxia Wang, Jirun Luo, Qinglan Zhao","doi":"10.1109/IVEC.2011.5747029","DOIUrl":"https://doi.org/10.1109/IVEC.2011.5747029","url":null,"abstract":"This paper introduces plasma-sprayed technique, mainly focusing on the improved emission properties of plasma-sprayed oxide cathode and some problems to be solved in the future.","PeriodicalId":106174,"journal":{"name":"2011 IEEE International Vacuum Electronics Conference (IVEC)","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132239709","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 : 2011-02-21DOI: 10.1109/IVEC.2011.5746851
J. Booske
A recent resurgence of interest in new, more powerful, coherent sources of terahertz (THz) radiation (0.3–3.0 × 1012 Hz) has been driven by advances in fabrication and device physics modeling, emergence of new security threats, and application potential in high data rate communications, concealed weapon or threat detection, remote high resolution imaging, chemical spectroscopy, materials research, deep space research and communications, basic biological spectroscopy and biomedical diagnostics. This talk reviews recent advances and achievements in THz-regime vacuum electronic devices (VEDs). VEDs are intrinsically superior to solid state devices at handling high power or high power density. Development of VED sources of THz radiation has therefore primarily focused on applications calling for either high average power or high average power density, i.e., relatively high power in a compact package, and usually with the highest achievable device efficiencies. The VED source and critical enabling technology advances reviewed in this talk include EIKs, BWOs, TWTs, gyrotrons, FELs, beamline sources, microfabrication and cathodes.
{"title":"Vacuum electronic sources for high power terahertz-regime radiation","authors":"J. Booske","doi":"10.1109/IVEC.2011.5746851","DOIUrl":"https://doi.org/10.1109/IVEC.2011.5746851","url":null,"abstract":"A recent resurgence of interest in new, more powerful, coherent sources of terahertz (THz) radiation (0.3–3.0 × 1012 Hz) has been driven by advances in fabrication and device physics modeling, emergence of new security threats, and application potential in high data rate communications, concealed weapon or threat detection, remote high resolution imaging, chemical spectroscopy, materials research, deep space research and communications, basic biological spectroscopy and biomedical diagnostics. This talk reviews recent advances and achievements in THz-regime vacuum electronic devices (VEDs). VEDs are intrinsically superior to solid state devices at handling high power or high power density. Development of VED sources of THz radiation has therefore primarily focused on applications calling for either high average power or high average power density, i.e., relatively high power in a compact package, and usually with the highest achievable device efficiencies. The VED source and critical enabling technology advances reviewed in this talk include EIKs, BWOs, TWTs, gyrotrons, FELs, beamline sources, microfabrication and cathodes.","PeriodicalId":106174,"journal":{"name":"2011 IEEE International Vacuum Electronics Conference (IVEC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130049224","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 : 2011-02-21DOI: 10.1109/IVEC.2011.5746910
D. T. Lopes, C. Motta
In this work, we present a comparison between plasma reduction factors for the case of a pencil e-beam inside a hollow metallic pipe. The values under comparison were obtained via analytic expressions given in the literature and the result of a 1D large signal time domain code. The main distinctive feature of this analysis is the additional consideration of dc space charge forces, since the actual electrostatic force among particles is computed, instead of making the assumption of a neutralizer background. In this way, the propagation of space charge waves can be simulated and the reduced plasma wavelength can be obtained. Simulated results were compared to three others obtained via formulae in the literature. A discrepancy of 1.6∼5.4% for a klystron example and 0.7∼2.2% for a TWT example, between analytic and simulated results were observed.
{"title":"Comparison of plasma frequency reduction factors simulated via 1D time domain lagrangian code and expressions in the literature","authors":"D. T. Lopes, C. Motta","doi":"10.1109/IVEC.2011.5746910","DOIUrl":"https://doi.org/10.1109/IVEC.2011.5746910","url":null,"abstract":"In this work, we present a comparison between plasma reduction factors for the case of a pencil e-beam inside a hollow metallic pipe. The values under comparison were obtained via analytic expressions given in the literature and the result of a 1D large signal time domain code. The main distinctive feature of this analysis is the additional consideration of dc space charge forces, since the actual electrostatic force among particles is computed, instead of making the assumption of a neutralizer background. In this way, the propagation of space charge waves can be simulated and the reduced plasma wavelength can be obtained. Simulated results were compared to three others obtained via formulae in the literature. A discrepancy of 1.6∼5.4% for a klystron example and 0.7∼2.2% for a TWT example, between analytic and simulated results were observed.","PeriodicalId":106174,"journal":{"name":"2011 IEEE International Vacuum Electronics Conference (IVEC)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134546309","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 : 2011-02-21DOI: 10.1109/IVEC.2011.5746957
U. Pal, P. Gulati, N. Kumar, M. Kumar, M. Tyagi, B. L. Meena, A. Sharma, R. Prakash
In this paper a Xenon filled coaxial dielectric barrier discharge (DBD) has been studied to understand the high pressure, non-equilibrium, nonthermal plasma discharge. A quartz coaxial DBD tube (ID: 6mm, OD: 12 mm) at 400 mbar Xenon filled pressure has been used in the experiment. Different applied voltage waveforms at 30 kHz using RF generator as well as pulse power source have been applied to the discharge electrodes for the generation of microdischarges. Visual images of discharge and electrical waveform confirm the diffused type discharges. The knowledge obtained by dynamic processes of DBDs in the discharge gap explains quantitatively the mechanism that is obtained in ignition, development and extinction of DBDs. The behaviour of different discharge parameters has also been analyzed. From the experimental results and equivalent electrical circuit, the dynamic nature of equivalent capacitance has been reported. The relative intensity analysis of the second continuum of the Xe discharge (172 nm) has been carried out for different applied voltages and it is found that the radiation power has increased with voltage.
{"title":"Investigation of discharge parameters in Xenon filled coaxial DBD tube","authors":"U. Pal, P. Gulati, N. Kumar, M. Kumar, M. Tyagi, B. L. Meena, A. Sharma, R. Prakash","doi":"10.1109/IVEC.2011.5746957","DOIUrl":"https://doi.org/10.1109/IVEC.2011.5746957","url":null,"abstract":"In this paper a Xenon filled coaxial dielectric barrier discharge (DBD) has been studied to understand the high pressure, non-equilibrium, nonthermal plasma discharge. A quartz coaxial DBD tube (ID: 6mm, OD: 12 mm) at 400 mbar Xenon filled pressure has been used in the experiment. Different applied voltage waveforms at 30 kHz using RF generator as well as pulse power source have been applied to the discharge electrodes for the generation of microdischarges. Visual images of discharge and electrical waveform confirm the diffused type discharges. The knowledge obtained by dynamic processes of DBDs in the discharge gap explains quantitatively the mechanism that is obtained in ignition, development and extinction of DBDs. The behaviour of different discharge parameters has also been analyzed. From the experimental results and equivalent electrical circuit, the dynamic nature of equivalent capacitance has been reported. The relative intensity analysis of the second continuum of the Xe discharge (172 nm) has been carried out for different applied voltages and it is found that the radiation power has increased with voltage.","PeriodicalId":106174,"journal":{"name":"2011 IEEE International Vacuum Electronics Conference (IVEC)","volume":"135 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134175278","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}
Possible chemical reaction in the scandate cathode at different temperature has been discussed in this paper.
本文讨论了在不同温度下钪阴极中可能发生的化学反应。
{"title":"XRD analysis of scandate cathodes","authors":"W. Liu, Jinshu Wang, Yiman Wang, Yuntao Cui, Xizhu Zhang, Meiling Zhou","doi":"10.1109/IVEC.2011.5747048","DOIUrl":"https://doi.org/10.1109/IVEC.2011.5747048","url":null,"abstract":"Possible chemical reaction in the scandate cathode at different temperature has been discussed in this paper.","PeriodicalId":106174,"journal":{"name":"2011 IEEE International Vacuum Electronics Conference (IVEC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131020051","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 : 2011-02-21DOI: 10.1109/IVEC.2011.5746951
A. Grede, H. Henke, R. Sharma
CEERI and TU-Berlin have recently started a cooperation to design and build a W-band folded waveguide TWT. In this paper and the corresponding talk we give an insight into the design process of the slow wave structure and present detailed simulation results of the chosen folded waveguide. Due to the long calculation times of the complete structure, pic simulation were still running when writing this abstract. First results look very promising and will we presented in the talk. We are confident to present cold measurement results during the conference as well.
{"title":"RF-structure design for the W-band folded waveguide TWT project of CEERI","authors":"A. Grede, H. Henke, R. Sharma","doi":"10.1109/IVEC.2011.5746951","DOIUrl":"https://doi.org/10.1109/IVEC.2011.5746951","url":null,"abstract":"CEERI and TU-Berlin have recently started a cooperation to design and build a W-band folded waveguide TWT. In this paper and the corresponding talk we give an insight into the design process of the slow wave structure and present detailed simulation results of the chosen folded waveguide. Due to the long calculation times of the complete structure, pic simulation were still running when writing this abstract. First results look very promising and will we presented in the talk. We are confident to present cold measurement results during the conference as well.","PeriodicalId":106174,"journal":{"name":"2011 IEEE International Vacuum Electronics Conference (IVEC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130745022","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 : 2011-02-21DOI: 10.1109/IVEC.2011.5746867
S. Dwivedi, P. K. Jain
MILO has been analyzed for its beam wave interaction and the RF released energy has been calculated. The analytical results are obtained, typically, for a S-band MILO, and released RF energy is found as 2.5 Joule at 300kV applied voltage. The analytical results has also been validated through PIC simulation code MAGIC and found to be in close agreement.
{"title":"Energy calculation for magnetically insulated line oscillator","authors":"S. Dwivedi, P. K. Jain","doi":"10.1109/IVEC.2011.5746867","DOIUrl":"https://doi.org/10.1109/IVEC.2011.5746867","url":null,"abstract":"MILO has been analyzed for its beam wave interaction and the RF released energy has been calculated. The analytical results are obtained, typically, for a S-band MILO, and released RF energy is found as 2.5 Joule at 300kV applied voltage. The analytical results has also been validated through PIC simulation code MAGIC and found to be in close agreement.","PeriodicalId":106174,"journal":{"name":"2011 IEEE International Vacuum Electronics Conference (IVEC)","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133039897","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 : 2011-02-21DOI: 10.1109/IVEC.2011.5746980
J. Jin, G. Gantenbein, S. Kern, T. Rzesnicki, M. Thumm
The paper presents the design of a MOU for the coaxial ITER gyrotron. Corrugated waveguides are used to transmit the high power mm-waves generated by gyrotrons to the plasma for Electron Cyclotron Resonance Heating (ECRH) and Current Drive (CD). The MOU contains two focusing mirrors, which are used to convert the gyrotron output into a Gaussian distribution with optimal parameters to improve the coupling efficiency of the TEM00 Gaussian distribution to the HE11 mode of the corrugated waveguide. The calculation results reveal that the coupling efficiency of the Gaussian beam to the HE11 mode is approximately 96.33%.
{"title":"Design of matching optics unit (MOU) for coaxial ITER gyrotron","authors":"J. Jin, G. Gantenbein, S. Kern, T. Rzesnicki, M. Thumm","doi":"10.1109/IVEC.2011.5746980","DOIUrl":"https://doi.org/10.1109/IVEC.2011.5746980","url":null,"abstract":"The paper presents the design of a MOU for the coaxial ITER gyrotron. Corrugated waveguides are used to transmit the high power mm-waves generated by gyrotrons to the plasma for Electron Cyclotron Resonance Heating (ECRH) and Current Drive (CD). The MOU contains two focusing mirrors, which are used to convert the gyrotron output into a Gaussian distribution with optimal parameters to improve the coupling efficiency of the TEM00 Gaussian distribution to the HE11 mode of the corrugated waveguide. The calculation results reveal that the coupling efficiency of the Gaussian beam to the HE11 mode is approximately 96.33%.","PeriodicalId":106174,"journal":{"name":"2011 IEEE International Vacuum Electronics Conference (IVEC)","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133598365","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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