Injection and acceleration of charged nano-dust particles from sungrazing comets

2012 ◽  
Author(s):  
Wing-Huen Ip ◽  
Tai-Hao Yan
Keyword(s):  
Dust Particles ◽  
Sungrazing Comets

Saturn's E, G and F rings: modulated by the plasma sheet

1984 ◽  
Vol 75 ◽  
pp. 597
Author(s):  
E. Grün ◽  
G.E. Morfill ◽  
T.V. Johnson ◽  
G.H. Schwehm
Keyword(s):  
Solar Wind ◽  
Direct Contact ◽  
Transport Processes ◽  
Time Variable ◽  
Dust Particles ◽  
Spatial Diffusion ◽  
Drag Forces ◽  
Orbit Perturbation ◽  
Time Variations ◽  
F Ring

ABSTRACTSaturn's broad E ring, the narrow G ring and the structured and apparently time variable F ring(s), contain many micron and sub-micron sized particles, which make up the “visible” component. These rings (or ring systems) are in direct contact with magnetospheric plasma. Fluctuations in the plasma density and/or mean energy, due to magnetospheric and solar wind processes, may induce stochastic charge variations on the dust particles, which in turn lead to an orbit perturbation and spatial diffusion. It is suggested that the extent of the E ring and the braided, kinky structure of certain portions of the F rings as well as possible time variations are a result of plasma induced electromagnetic perturbations and drag forces. The G ring, in this scenario, requires some form of shepherding and should be akin to the F ring in structure. Sputtering of micron-sized dust particles in the E ring by magnetospheric ions yields lifetimes of 102to 104years. This effect as well as the plasma induced transport processes require an active source for the E ring, probably Enceladus.

Analytical Electron Microscopy Characterization of Electric Arc Furnace Dust

1981 ◽  
Vol 39 ◽  
pp. 134-135
Author(s):  
J. R. Porter ◽  
J. I. Goldstein ◽  
D. B. Williams
Keyword(s):  
Electron Microscopy ◽  
Analytical Electron Microscopy ◽  
Electric Arc Furnace ◽  
Electric Arc ◽  
Dust Particles ◽  
Particle Analysis ◽  
Arc Furnace ◽  
Analytical Electron ◽  
Residual Elements ◽  
Industry Practice

Alloy scrap metal is increasingly being used in electric arc furnace (EAF) steelmaking and the alloying elements are also found in the resulting dust. A comprehensive characterization program of EAF dust has been undertaken in collaboration with the steel industry and AISI. Samples have been collected from the furnaces of 28 steel companies representing the broad spectrum of industry practice. The program aims to develop an understanding of the mechanisms of formation so that procedures to recover residual elements or recycle the dust can be established. The multi-phase, multi-component dust particles are amenable to individual particle analysis using modern analytical electron microscopy (AEM) methods.Particles are ultrasonically dispersed and subsequently supported on carbon coated formvar films on berylium grids for microscopy. The specimens require careful treatment to prevent agglomeration during preparation which occurs as a result of the combined effects of the fine particle size and particle magnetism. A number of approaches to inhibit agglomeration are currently being evaluated including dispersal in easily sublimable organic solids and size fractioning by centrifugation.

Improving soil remediation through characterization

1995 ◽  
Vol 53 ◽  
pp. 386-387
Author(s):  
E. C. Buck ◽  
N. L. Dietz ◽  
J. K. Bates
Keyword(s):  
Dust Particles ◽  
Radiochemical Analysis ◽  
Solid Product ◽  
Uranium Contamination ◽  
Physical Separation ◽  
X Ray ◽  
Rocky Flats ◽  
Remediation Strategies ◽  
Bearing Materials ◽  
X Ray Absorption

Operations at former weapons processing facilities in the U. S. have resulted in a large volume of radionuclidecontaminated soils and residues. In an effort to improve remediation strategies and meet environmental regulations, radionuclide-bearing particles in contaminant soils from Fernald in Ohio and the Rocky Flats Plant (RFP) in Colorado have been characterized by electron microscopy. The object of these studies was to determine the form of the contaminant radionuclide, so that it properties could be established [1]. Physical separation and radiochemical analysis determined that uranium contamination at Fernald was not present exclusively in any one size/density fraction [2]. The uranium-contamination resulted from aqueous and solid product spills, air-borne dust particles, and from the operation of an incinerator on site. At RFP the contamination was from the incineration of Pu-bearing materials. Further analysis by x-ray absorption spectroscopy indicated that the majority of the uranium was in the 6+ oxidation state [3].

Charge distribution on dust particles of space plasma

2003 ◽  
Vol 9 (4) ◽  
pp. 67-72 ◽  
Author(s):  
Yu.O. Klymenko ◽  
◽  
О.К. Cheremnykh ◽  
Keyword(s):  
Charge Distribution ◽  
Space Plasma ◽  
Dust Particles

INSTABILITY OF HYDROMAGNETIC FLUIDS STREAMING IN A POROUS MEDIUM WITH SUSPENDED DUST PARTICLES

2013 ◽  
Vol 16 (12) ◽  
pp. 1063-1074 ◽  
Author(s):  
Praveen K. Sharma ◽  
Anita Tiwari ◽  
Rajendra K. Chhajlani
Keyword(s):  
Porous Medium ◽  
Dust Particles ◽  
Suspended Dust

Trajectory and Thermal Analysis for Disk-shaped Dust Particles through a Shock Layer

2014 ◽  
Author(s):  
Yoshihiro Toki ◽  
Yousuke Ogino ◽  
Naofumi Ohnishi ◽  
Keisuke Sawada
Keyword(s):  
Thermal Analysis ◽  
Shock Layer ◽  
Dust Particles

Antiprobcotron magnetic trap for charged dust particles in space experiments

2019 ◽  
pp. 20-29
Author(s):  
Lev G. D’YACHKOV ◽  
Mikhail M. VASILYEV ◽  
Oleg F. PETROV ◽  
Sergey F. SAVIN ◽  
Igor V. CHURILO
Keyword(s):  
Magnetic Trap ◽  
Space Station ◽  
Coulomb Systems ◽  
Inhomogeneous Magnetic Field ◽  
Dust Particles ◽  
Charged Dust ◽  
Magnetic Traps ◽  
Space Experiments ◽  
Microgravity Conditions ◽  
New Space

We discuss the possibility of using static magnetic traps as an alternative to electrostatic traps for forming and confining structures of charged dust particles in a gas discharge plasma in the context of our study of strongly interacting Coulomb systems. Some advantages of confining structures in magnetic traps over electrostatic ones are shown. Also we provide a review of the related researches carried out first in laboratory conditions, and then under microgravity conditions including the motivation of performing the experiments aboard the International Space Station (ISS). The preparations of a new space experiment «Coulomb-magnet» as well as the differences of a new equipment from previously used are described. We proposed the main tasks of the new experiment as a study of the dynamics and structure of active monodisperse and polydisperse macroparticles in an inhomogeneous magnetic field under microgravity conditions, including phase transitions and the evolution of such systems in the kinetic heating of dust particles by laser radiation. Key words: Coulomb structures, magnetic trap, antiprobotron, diamagnetic particles, dust particles, microgravity.

Sign in / Sign up

Export Citation Format

Share Document