In this work, a self-consistent model has been used to estimate the effective secondary electron emission coefficient (γE) of cathode in typical abnormal dc glow discharge conditions. Using model, value γE obtained for tungsten (W), copper (Cu), and stainless steel (SS304) samples argon (Ar) nitrogen (N2) discharges. The W is lower than Cu under identical operating results show possible dependence on Fermi energy material since it influences probability be emitted by incident ion. addition...

Sounds in large cities are usually characterized by multi-source overlaying components. This makes environment sound quality difficult to interpret, thus requiring different investigation approaches. is the case of urban parks where coexistence anthropogenic and biophonic sources evaluation local soundscape challenging. In this context, we applied transfer entropy measure extract additional information with respect more classical approach eco-acoustics. The study refers Parco Nord Milan,...

We present direct evidence for the existence of self-organized critical behavior in cold plasma. A multiple anodic double layer structure generated a discharge plasma setup shows anode bias above threshold value. Analysis floating potential fluctuations reveals long-range time correlations and power law tail probability distribution function fluctuations. The measured Hurst exponent rank are strong indication system hence provide condition under which complexities arise

The role of self-organized criticality (SOC) in the transformation multiple anodic double layers (MADLs) from stable to turbulent regime has been investigated experimentally as system approaches towards critical behavior. experiment was performed a modified glow discharge plasma setup, and initial state MADL comprising three concentric perceptible produced when drift velocity electrons anode exceeds electron thermal (νd ≥ 1.3νte). macroscopic arrangement both positive negative charges...

Feedback is said to exist in any amplifier when the fraction of output power fed back as an input. Similarly, gaseous discharge ions that incident on cathode act a natural feedback element stabilize and self sustain discharge. The present investigation intended emphasize nature emits secondary electrons (SEs) from surface DC gas discharges. average number SEs emitted per ion non ionic species (energetic neutrals, metastables photons) which results defined effective electron emission...

Background: Emission of Secondary electron from material surface is the key parameter which defines all properties plasma bounded by that surface. In dc glow discharge plasmas, these emitted electrons cathode provide necessary feedback to sustain discharge. There are various processes responsible for emission The most dominant among bombardment energetic neutrals, excited atoms or molecules, photons, reactions etc. in addition ion induced secondary emission. Further, governing contribution...

Abstract A steady regime dominated by intermittent blob and hole structures is identified in the plasma state of a simple magnetized torus achieving quasi-stationary equilibrium using an open magnetic field line configuration. The helical configuration characterized connection length, <?CDATA ${L}_{c}=2a\left(\tfrac{{B}_{\varphi }}{{B}_{z}}\right)\gtrsim 1750$?> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msub> <mml:mrow> <mml:mi>L</mml:mi> </mml:mrow>...

Abstract A noninvasive diagnostic technique relying on optical emission spectroscopy is used for studying plasma confined in a purely toroidal magnetic field. Visible lines of molecular hydrogen were specifically targeted. Bi-dimensional structures and poloidal profiles reconstructed from the emissivity distribution Fulcher system using tomographic method. few details concerning methods employed to capture different viewlines, data reduction reconstruction techniques are also addressed. We...

An exact calculation of N2+ and H2+ influx, at cathode surface in N2–H2 discharge, has been derived using electron impact ionization cross-section plasma sheath boundary. The analytical formula is very convenient practical applications. Through the analysis experimental parameters for glow discharge nitriding, explains, why treatment an mixture with H2 percentage ∼70% gives most enhanced result.

We presents results obtained from the numerical simulation of gas-phase chemical kinetics in atmospheric pressure air non-equilibrium plasmas. In particular we have addressed effect pulsed operation mode a planar dielectric barrier discharge. As it was conjectured, large difference time scales involved fast dissociation molecules plasmas and their subsequent reactions to produce stable species, makes presence continuously repeated plasma production stage unnecessary waste electrical power...

We present results obtained from the numerical simulation of gas-phase chemical kinetics in atmospheric pressure air non-equilibrium plasmas. In particular, we addressed effect pulsed operation mode a planar dielectric barrier discharge. As conjectured, large difference time scales involved fast dissociation molecules plasmas and their subsequent reactions to produce stable species makes presence continuously repeated plasma production stage unnecessary waste electrical power efficiency. The...

Abstract A double plasma device (DPD) is tested for different operational configurations to identify suitable control parameters in a weakly ionized, unmagnetized discharge. separation grid installed between the two chambers of DPD, which allows filtering from first second chamber. Investigations are carried out parameters, especially electron temperature by exploring role grid. The bias varied −25–0 V and 0–30 reflect cooling heating plasma. prominent maximum ratio n source / target ....

Views Icon Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Twitter Facebook Reddit LinkedIn Tools Reprints and Permissions Cite Search Site Citation Ram Niranjan, R. K. Rout, Srivastava, Y. Chakravarthy, N. Patel, P. Alex, Satish C. Gupta; Response of nickel surface to pulsed fusion plasma radiations. AIP Conference Proceedings 24 April 2014; 1591 (1): 910–912. https://doi.org/10.1063/1.4872799 Download citation file: Ris (Zotero) Reference Manager EasyBib...

We discuss the measurement of electric field drift (E→xB→ velocity) and its spatial derivatives in a low temperature magnetized plasma by means suitably arranged multi-pin Langmuir probe. Results are presented relating properties velocity electrostatic fluctuations. In particular, we have measured components non-linear terms fluid magnetohydrodynamics equation.

We have analyzed the electrical characteristics of a plug probe as function orientation relative to local magnetic field. Our aim was demonstrate that characteristic, besides better evaluation plasma potential, retains capability reliably estimate electron temperature and density. This feature could be exploited with multi-pin measure simultaneously fluctuations all parameters.

Radial control of the electron temperature gradient is demonstrated in a double plasma device by making use segmented grid biasing. The produced source region allowed to diffuse into target through single as well cassette multiple assembly, under different bias conditions. Both heating and cooling are observed radially at one location when used. electrons cooled down 3.3 eV from 5.1 raised −25 0 V. Similarly, during heating, increases 4.8 7.3 varied between +20 Two transparencies grids, 45%...

Low-temperature plasma (LTP) processing is a green and flexible food technology with only known limitation of low energy efficiency. Three established fundamental mechanisms includes: i) physical damage to membranes internal cellular components due bombardment energetic ions: ii) radicals charged species led chemical reactions: iii) radiation-induced modifications. In this investigation, we present new mechanism generation extraction $N_2$ neutrals from glow discharge plasmas for efficient...