纳米技术与医学中的非局域等离子体国际实验室
简介
The Laboratory is established under open grant competition of the Government of the Russian Federation designed to support research projects implemented by leading scientists at Russian institutions of higher education (Resolution of the Government of the Russian Federation No.220 adopted on April 9, 2010) Professor of West Virginia University, USA - Vladimir Demidov
The main topics of the Laboratory research activity:
· Fundamental and applied physics and chemistry of plasma,
· Computer modeling,
· Applications of plasma in modern technologies and new devices (in particular, in nano-technology and Biomedicine).
The results of the work of the participants of the project are published in 7 monographs, more than 250 articles indexed in Web of Science and Scopus top-rated journals with high impact factor, the writings of numerous international scientific conferences (more than 200 reports) and many Russian and foreign patents, including in the field of plasma applications. The participants of the created team have extensive experience of teaching and creation of new educational programs of undergraduate, graduate and postgraduate studies. The Laboratory staff are the authors of many books, including interactive electronic publications, using multimedia technologies
Research Areas
Study of parameters of nonlocal plasma modified short gas DC discharge with hot cathode
A short dc discharge with a thermionic cathode can be used as a current and voltage stabilizer, but is subject to current oscillation. If instead of one anode two anodes are used, the current oscillations can be reduced. We have developed a kinetic model of such a discharge with two anodes, where the primary anode has a small opening for passing a fraction of the discharge current to an auxiliary anode. The model demonstrates that the current-voltage relationship of the discharge with two anodes is characterized everywhere by positive slope, i.e., positive differential resistance. Therefore, the discharge with two anodes is expected to be stable to the spontaneous oscillation in current that is induced by negative differential resistance. As a result, such a discharge can be used in an engineering application that requires stable plasma, such as a current and voltage stabilizer.
Plasma-chemical simulation of discharges in gases SF6 и O2
Numerical modeling and theoretical analyses of spatial distribution with detailed set of plasmachemical processes in elegas have been made for a wide range of pressures. Evolutionof main charged and neutral particles in time and space has been obtained. It is shown that at low pressures, the Boltzmann distribution holds for both electrons and negative ions and separation of the plasma into two regions with an almost flat profile of the electron density. At high pressures, electronegativity of plasma is extremely high and the self-consistent electric field is determined not only by the electrons, as in the conventional plasma, but also by the ions of both signs. This leads to an abnormally small potential drop in the plasma and nonmonotonic ion profiles.
Index Terms—Plasma properties, plasma simulation, plasma sources, plasma transport processes, plasmas.
Studying of features of the drift of particles in the plasma due to specific functions of the electron energy distribution in a nonlocal plasma
Gyro-phase drift is a guiding center drift that is directly dependent on the charging rate limit of dust grains. The effect of introducing a gyro-phase-dependence
on the grain charge leads to two orthogonal components of guiding-center drift. One component, referred to here as grad-q drift, results from the time-varying, gyro-phase
angle dependent, in-situ-equilibrium grain charge, assuming that the grain charging is instantaneous. For this component, the grain is assumed to be always in its insitu-
equilibrium charge state and this state gyro-synchronously varies with respect to the grain’s average charge state. The other component, referred to here as the
gyro-phase drift, arises from any non-instantaneous-charging-induced modification of the diamagnetic drift and points in the direction of −∇RLd (where RLd is the
grain gyro-radius), i.e. the direction associated with increasing magnitude of insitu- equilibrium charge state. For this component, the grain gyro-synchronously
undercharges and overcharges with respect to its gyro-synchronously varying, insitu-equilibrium charge state. These characteristics are illustrated with a singleparticle
code for predicting grain trajectory that demonstrates how gyro-phase drift magnitude and direction could be exploited, using an extended version of the presented model, as sensitive indicators of the charging time of dust grains because of the cumulative effect of the ever-changing charge state of a grain making repeated excursions in inhomogeneous plasma over many gyro-periods.
Simulation of discharge using analytical methods
The new applications of computer technologies to the teaching of experimental physics are presented. The upgrades of the laboratory sessions «Investigation spontaneous gas discharge in air» by computer simulation of gas discharge plasma has been proposed as a way of transformation of experimental training up to the self-sufficient student’s research. The ways of plasma micro- and macro modeling are discussed. The comparison of experimental data with plasma macro modeling results are presented together with some next steps of lab-experiments and computer-simulations symbiosis development.
联系方式
副教授, PhD
+7 (921) 9153429
alex_chirtsov@mail.ru