Gravitational Drift Instability in Quantum Dusty Plasmas

2018 ◽  
Vol 73 (12) ◽  
pp. 1137-1141 ◽  
Author(s):  
M. Jamil ◽  
Zahid Mir ◽  
A. Rasheed ◽  
A. Hussain
Keyword(s):  
Magnetic Field ◽  
Wide Spectrum ◽  
Dusty Plasmas ◽  
Dust Particles ◽  
Electrostatic Waves ◽  
Quantum Hydrodynamic Model ◽  
Plasma Species ◽  
Density Of Electrons ◽  
Drift Instability

AbstractThe dispersion relation of electrostatic waves due to multi-drifts is studied in an ambient magnetic field across three-species quantum dusty plasmas. The quantum hydrodynamic model is applied to analyze the effects of the Lorentz and the gravitational forces. It is found that the instability is excited mainly due to the \({\mathbf{E}_{0}}\times{\mathbf{B}_{0}}\) drift of the plasma species. However, an additional \({\mathbf{g}_{0}}\times{\mathbf{B}_{0}}\) drift associated with dust particles enhances the instability over a wide spectrum of wavevector. The role of a varying magnetic field and the number density of electrons in the wave instability are analyzed graphically. It is noticed that these factors have a significant contribution over the drift instability.

On the role of mother-planet magnetic field in spiral structure explanation of formation of spokes

1984 ◽  
Vol 75 ◽  
pp. 569-574
Author(s):  
G.X. Song
Keyword(s):  
Magnetic Field ◽  
Solar System ◽  
Interplanetary Magnetic Field ◽  
Wave Amplitude ◽  
Spiral Structure ◽  
Dust Particles ◽  
Electromagnetic Effect ◽  
Sectoral Structure ◽  
The Magnetic Field

AbstractSome features about the spokes in B rings can be explained in terms of the electromagnetic effect. Due to the existence of the magnetic field in Saturn, plasma and micro-sized dust particles, the loosely spiral structure of magnetic field near Saturn, which is similar to that invoked to explain the sectoral structure of the interplanetary magnetic field in the solar system, may be induced.The spiral structure is rotating with mother-planet and will gradually form at corotation circle, but the wave amplitude will grow outside the corotation and will decay gradually inside the corotation. Using the characteristics of this spiral structure, we have tried to attack the mechanism of the formation of spokes.

scholarly journals ON THE ROLE OF THE CURVATURE DRIFT INSTABILITY IN THE DYNAMICS OF ELECTRONS IN ACTIVE GALACTIC NUCLEI

2013 ◽  
Vol 22 (13) ◽  
pp. 1350081 ◽  
Author(s):  
ZAZA OSMANOV
Keyword(s):  
Magnetic Field ◽  
Active Galactic Nuclei ◽  
Galactic Nuclei ◽  
Rotational Energy ◽  
Relativistic Electrons ◽  
Field Lines ◽  
Drift Instability ◽  
The Magnetic Field ◽  
Relativistic Particles

We study the influence of the centrifugally driven curvature drift instability (CDI) on the dynamics of relativistic electrons in the magnetospheres of active galactic nuclei (AGN). We generalize in our previous paper by considering relativistic particles with different initial phases. Considering the Euler continuity and induction equations, by taking into account the resonant conditions, we derive the growth rate of the CDI. We show that due to the centrifugal effects, the rotational energy is efficiently pumped directly into the drift modes, that leads to the generation of a toroidal component of the magnetic field. As a result, the magnetic field lines transform into such a configuration when particles do not experience any forces and since the instability is centrifugally driven, at this stage the CDI is suspended.

scholarly journals The effect of a magnetic field on the dynamics of debris discs around white dwarfs

2020 ◽  
Vol 500 (3) ◽  
pp. 2986-3001
Author(s):  
M A Hogg ◽  
R Cutter ◽  
G A Wynn
Keyword(s):  
Magnetic Field ◽  
Particle Size ◽  
White Dwarfs ◽  
Accretion Rate ◽  
Observational Evidence ◽  
Dust Particles ◽  
Accretion Rates ◽  
Subsequent Effect ◽  
Similar Factor

ABSTRACT Observational estimates of the lifetimes and inferred accretion rates from debris discs around polluted white dwarfs are often inconsistent with the predictions of models of shielded Poynting–Robertson drag on the dust particles in the discs. Moreover, many cool polluted white dwarfs do not show any observational evidence of accompanying discs. This may be explained, in part, if the debris discs had shorter lifetimes and higher accretion rates than predicted by Poynting–Robertson drag alone. We consider the role of a magnetic field on tidally disrupted diamagnetic debris and its subsequent effect on the formation, evolution, and accretion rate of a debris disc. We estimate that magnetic field strengths greater than ∼10 kG may decrease the time needed for circularization and the disc lifetimes by several orders of magnitude and increase the associated accretion rates by a similar factor, relative to Poynting–Robertson drag. We suggest some polluted white dwarfs may host magnetic fields below the typical detectable limit and that these fields may account for a proportion of polluted white dwarfs with missing debris discs. We also suggest that diamagnetic drag may account for the higher accretion rate estimates among polluted white dwarfs that cannot be predicted solely by Poynting–Robertson drag and find a dependence on magnetic field strength, orbital pericentre distance, and particle size on predicted disc lifetimes and accretion rates.

scholarly journals The dielectric tensor for dusty magnetized plasmas with variable charge on dust particles

1998 ◽  
Vol 60 (2) ◽  
pp. 243-263 ◽  
Author(s):  
M. C. de JULI ◽  
R. S. SCHNEIDER
Keyword(s):  
Magnetic Field ◽  
Wave Propagation ◽  
External Magnetic Field ◽  
Dusty Plasmas ◽  
Dust Particles ◽  
Magnetosonic Wave ◽  
Dielectric Tensor ◽  
Magnetized Plasmas ◽  
Variable Charge ◽  
Electrons And Ions

We derive the dielectric tensor for multicomponent magnetized dusty plasmas, including the effect of capture of plasma electrons and ions by the dust particles. For propagation perpendicular to the external magnetic field and Maxwellian distributions of electrons and ions, we obtain compact expressions for the components of the dielectric tensor, which can be used to analyse wave propagation. An application to the magnetosonic wave is presented.

Relaxed states in electron-depleted electronegative dusty plasmas with two-negative ion species

2013 ◽  
Vol 80 (1) ◽  
pp. 59-65 ◽  
Author(s):  
M. Iqbal
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
Dusty Plasma ◽  
Negative Ions ◽  
Dusty Plasmas ◽  
Numerical Results ◽  
Negative Ion ◽  
Inertial Forces ◽  
Plasma Species ◽  
Ion Species

AbstractThe relaxation of an electron-depleted electronegative dusty plasma with two-negative ions is investigated. When the ratio of canonical vorticities to corresponding flows of all the plasma species is the same and all inertial and non-inertial forces are present, the relaxed state appears as a double Beltrami magnetic field which is the superposition of two force-free relaxed states. The numerical results show that highly diamagnetic relaxed magnetic fields can be obtained by controlling the flow and vorticities through a single Beltrami parameter. The study is useful to investigate the creation of diamagnetic plasma configurations which are considered to be very important in the context of nuclear fusion.

The potential role of tea in periodontal therapy: An updated review

2020 ◽  
Vol 17 ◽  
Author(s):  
Ali Forouzanfar ◽  
Hamideh Sadat Mohammadipour ◽  
Fatemeh Forouzanfar
Keyword(s):  
Green Tea ◽  
Potential Role ◽  
Wide Spectrum ◽  
Periodontal Diseases ◽  
Herbal Remedies ◽  
World Population ◽  
Tea Leaves ◽  
The World ◽  
Green Tea Leaves

: Periodontal diseases are highly prevalent and can affect high percentage of the world population. Oxidative stress and inflammation plays an important role in the pathogenesis of periodontal diseases. Nowadays, more attention has been focused on the herbal remedies in the field of drug discovery. Green tea is an important source of polyphenol antioxidants, it has long been used as a beverage worldwide. The most interesting polyphenol components of green tea leaves that are related with health benefits are the catechins. Taken together this review suggested that green tea with its wide spectrum of activities could be a healthy alternative for controlling the damaging reactions seen in periodontal diseases.

Gut Mycobiota and Fungal Metabolites in Human Homeostasis

2018 ◽  
Vol 20 (2) ◽  
pp. 232-240 ◽  
Author(s):  
Izabella Mogilnicka ◽  
Marcin Ufnal
Keyword(s):  
Wide Spectrum ◽  
Biological Effects ◽  
Fungal Species ◽  
Fungal Metabolites ◽  
Human Gut ◽  
Fecal Transplantation ◽  
Bacterial Microbiota ◽  
Bowel Diseases ◽  
Inflammatory Bowel

Background:Accumulating evidence suggests that microbiota play an important role in host’s homeostasis. Thus far, researchers have mostly focused on the role of bacterial microbiota. However, human gut is a habitat for several fungal species, which produce numerous metabolites. Furthermore, various types of food and beverages are rich in a wide spectrum of fungi and their metabolites.Methods:We searched PUBMED and Google Scholar databases to identify clinical and pre-clinical studies on fungal metabolites, composition of human mycobiota and fungal dysbiosis.Results:Fungal metabolites may serve as signaling molecules and exert significant biological effects including trophic, anti-inflammatory or antibacterial actions. Finally, research suggests an association between shifts in gut fungi composition and human health. Changes in mycobiota composition have been found in obesity, hepatitis and inflammatory bowel diseases.Conclusion:The influence of mycobiota and dietary fungi on homeostasis in mammals suggests a pharmacotherapeutic potential of modulating the mycobiota which may include treatment with probiotics and fecal transplantation. Furthermore, antibacterial action of fungi-derived molecules may be considered as a substitution for currently used antibacterial agents and preservatives in food industry.

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