排序方式: 共有26条查询结果,搜索用时 0 毫秒
21.
J. Adámek J. Stöckel I. Ďuran M. Hron R. Pánek M. Tichý R. Schrittwieser C. Ionit P. Balan E. Martines G. Van Oost 《Czechoslovak Journal of Physics》2005,55(3):235-242
A novel approach to the direct measurement of the plasma potential in magnetized plasmas, using the so-called “ball-pen probe”, was recently tested in the CASTOR tokamak. Comparison with the standard technique of plasma potential measurement using the emissive probe is reported. It is found that the plasma potential determined by the emissive probe is systematically lower than that measured by the ball-pen probe. The difference is of the of the of kT e/e. A possible reason of this difference is the space charge occurring in the proximity of the emissive probe. 相似文献
22.
J. Adámek I. Ďuran M. Hron J. Stöckel P. Balan R. Schrittwieser C. Ionita E. Martines M. Tichý G. Van Oost 《Czechoslovak Journal of Physics》2002,52(10):1115-1120
A new probe head, composed of two electro-emissive probes and two Langmuir probes has been designed to measure edge fluctuations in the CASTOR tokamak. In this contribution, only one Langmuir and one electron-emissive probe are used to measure the temperature and potential fluctuations and the phase angle between them. 相似文献
23.
J. Adámek J. Stöckel M. Hron J. Ryszawy M. Tichý R. Schrittwieser C. Ionită P. Balan E. Martines G. Van Oost 《Czechoslovak Journal of Physics》2004,54(3):C95
A novel probe and approach to the direct measurements of the plasma potential in a strong magnetic field is suggested. The principle of this method is to reduce the electron saturation current to the same magnitude as that of the ion saturation current. In this case, the floating potential of the probe becomes indentical to the plasma potential. This goal is attained by a shield, which screens off an adjustable part of the electron current from the probe collector due to the much smaller gyro-radius of the electrons. First systematic measurements have been perfomred in the CASTOR tokamak. 相似文献
24.
Spada E Carbone V Cavazzana R Fattorini L Regnoli G Vianello N Antoni V Martines E Serianni G Spolaore M Tramontin L 《Physical review letters》2001,86(14):3032-3035
In order to test the self-organized criticality (SOC) paradigm in transport processes, a novel technique has been applied for the first time to plasmas confined in reversed field pinch configuration. This technique consists of an analysis of the probability distribution function of the times between bursts in density fluctuations measured by microwave reflectometry and electrostatic probes. The same analysis has also been applied to intermittent events sorted out from the Gaussian background. In both cases, the experimental results disagree with the predictions for a SOC system. 相似文献
25.
Martines Marco Antonio Utrera do Carmo Devaney Ribeiro de Castro Gustavo Rocha Caetano Laércio 《Journal of Sol-Gel Science and Technology》2011,59(1):188-193
This paper reports an electrochemical study of ordered mesoporous silica impregnated with a cationic dye (o-toluidine blue),
prepared with a non-ionic surfactant as the structure-directing agent. O-toluidine blue was chosen because of its utility
as an electron transfer mediator (redox catalyst). O-toluidine blue impregnated mesoporous silica was characterized by nitrogen
sorption porosimetry, small angle X-ray scattering, infrared spectroscopy, scanning electron microscopy and cyclic voltammetry
using chemically modified carbon paste electrodes. Results indicate that the dye is located within the ordered mesopores of
micron-sized silica spheres. 相似文献
26.
Ian P. Martines Hristo V. Kojouharov James P. Grover 《Applied mathematics and computation》2009,215(2):573-582
Presented is a chemostat model in which one microbial population excretes a poison that increases the mortality of another, with toxin production increasing as the growth rate of the toxic species decreases. The model is intended to explore the role of allelopathy in blooms of harmful algae, such as red tide (Karenia brevis) and golden algae (Prymnesium parvum). This study introduces the model and its biological basis, and proceeds to the analysis of its asymptotic states. All theoretical results are supported by a set of numerical simulations. A discussion of biological conclusions and similarities to other mathematical models is also presented. 相似文献