Name: experimental methods of dust charging and mobilization on surfaces with exposure to ultraviolet radiation or plasmas
Uploaded: 2018-04-03T13:30:00
Description: Watch this Scientific Journal Video about Experimental Methods of Dust Charging and Mobilization on Surfaces with Exposure to Ultraviolet Radiation or Plasmas at JoVE.com

This work was supported by the NASA/SSERVI&#39;s Institute for Modeling Plasma, Atmospheres and Cosmic Dust (IMPACT) and by the NASA Solar Systems Workings Program (Grant number: NNX16AO81G).

1. Vacuum chamber setup
<ol>
	<li>Place an insulating rubber sheet (0.2 cm thick, 5 cm in diameter) with a central hole 1.9 cm in diameter on an insulating plate (2 cm thick and 20 cm in diameter) (Figure 2a, b). Load insulating, irregularly-shaped dust particles (between 10 and 50 &#956;m in diameter) in the hole.</li>
	<li>Place the insulating plate on a metal plate standing in the middle of a vacuum chamber. Electrically isolate the metal plate from the chamber using ce...

<ol>
	<li>Criswell, D. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Horizon-glow+and+the+motion+of+lunar+dust.">Horizon-glow and the motion of lunar dust.</a> Photon and Particle Interactions with Surfaces in Space. , 545-556 (1973).</li><li>Rennilson, J. J., Criswell, D. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Surveyor+observations+of+lunar+horizon-glow.">Surveyor observations of lunar horizon-glow.</a> Moon. 10 (2), 121-142 (1974).</li><li>Colwell, J. E., Batiste, S., Hor&#225;nyi, M., Robertson, S., Sture, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Lunar+surface:+Dust+dynamics+and+regolith+mechanics.">Lunar surface: Dust dynamics and regolith mechanics.</a> Rev. Geophys. 45, RG2006 (2007).</li><li>McCoy, J. E., Criswell, D. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Evidence+for+a+high+latitude+distribution+of+lunar+dust.">Evidence for a high latitude distribution of lunar dust.</a> The 5th Proc. Lunar Sci. Conf. , 2991 (1974).</li><li>Zook, H. A., McCoy, J. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Large+scale+lunar+horizon+glow+and+a+high+altitude+lunar+dust+exosphere.">Large scale lunar horizon glow and a high altitude lunar dust exosphere.</a> Geophys. Res. Lett. 18 (11), 2117-2120 (1991).</li><li>Smith, B. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Encounter+with+Saturn+-+Voyager-1+imaging+science+results.">Encounter with Saturn - Voyager-1 imaging science results.</a> Science. 212 (4491), 163-191 (1981).</li><li>Smith, B. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+new+look+at+the+Saturn+system+-+the+Voyager-2+images.">A new look at the Saturn system - the Voyager-2 images.</a> Science. 215 (4532), 504-537 (1982).</li><li>Mitchell, C. J., Hor&#225;nyi, M., Havnes, O., Porco, C. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Saturn's+spokes:+Lost+and+found.">Saturn's spokes: Lost and found.</a> Science. 311 (5767), 1587-1589 (2006).</li><li>Robinson, M. S., Thomas, P. 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Astrophys. 583, A17 (2015).</li><li>Vernazza, P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High+surface+porosity+as+the+origin+of+emissivity+features+in+asteroid+spectra.">High surface porosity as the origin of emissivity features in asteroid spectra.</a> Icarus. 221 (2), 1162-1172 (2012).</li><li>Hirata, N., Miyamoto, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dust+levitation+as+a+major+resurfacing+process+on+the+surface+of+a+saturnian+icy+satellite+Atlas.">Dust levitation as a major resurfacing process on the surface of a saturnian icy satellite Atlas.</a> Icarus. 220 (1), 106-113 (2012).</li><li>Garrick-Bethell, I., Head, J. W., Pieters, C. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Spectral+properties,+magnetic+fields,+and+dust+transport+at+lunar+swirls.">Spectral properties, magnetic fields, and dust transport at lunar swirls.</a> Icarus. 212 (2), 480-492 (2011).</li><li>Murphy, T. W., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Long-term+degradation+of+optical+devices+on+the+Moon.">Long-term degradation of optical devices on the Moon.</a> Icarus. 208 (1), 31-35 (2010).</li><li>Sheridan, T. E., Goree, J., Chiu, Y. T., Rairden, R. L., Kiessling, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Observation+of+dust+shedding+from+material+bodies+in+a+plasma.">Observation of dust shedding from material bodies in a plasma.</a> J. Geophys. Res. 97 (A3), 2935-2942 (1992).</li><li>Flanagan, T. M., Goree, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dust+release+from+surfaces+exposed+to+plasma.">Dust release from surfaces exposed to plasma.</a> Phys. Plasmas. 13 (12), 123504 (2006).</li><li>Sickafoose, A. A., Colwell, J. E., Hor&#225;nyi, M., Robertson, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Experimental+levitation+of+dust+grains+in+a+plasma+sheath.">Experimental levitation of dust grains in a plasma sheath.</a> J. Geophys. Res. 107 (A11), 1408 (2002).</li><li>Wang, X., Hor&#225;nyi, M., Robertson, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Experiments+on+dust+transport+in+plasma+to+investigate+the+origin+of+the+lunar+horizon+glow.">Experiments on dust transport in plasma to investigate the origin of the lunar horizon glow.</a> J. Geophys. Res. 114, A05103 (2009).</li><li>Wang, X., Hor&#225;nyi, M., Robertson, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Investigation+of+dust+transport+on+the+lunar+surface+in+a+laboratory+plasma+with+an+electron+beam.">Investigation of dust transport on the lunar surface in a laboratory plasma with an electron beam.</a> J. Geophys. Res. 115, A11102 (2010).</li><li>Wang, X., Hor&#225;nyi, M., Robertson, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dust+transport+near+electron+beam+impact+and+shadow+boundaries.">Dust transport near electron beam impact and shadow boundaries.</a> Planet. Space Sci. 59 (14), 1791-1794 (2011).</li><li>Hartzell, C. M., Wang, X., Scheeres, D. J., Hor&#225;nyi, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Experimental+demonstration+of+the+role+of+cohesion+in+electrostatic+dust+lofting.">Experimental demonstration of the role of cohesion in electrostatic dust lofting.</a> Geophys. Res. Lett. 40 (6), 1038-1042 (2013).</li><li>Wang, X., Hor&#225;nyi, M., Sternovsky, Z., Robertson, S., Morfill, G. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+laboratory+model+of+the+lunar+surface+potential+near+boundaries+between+sunlit+and+shadowed+regions.">A laboratory model of the lunar surface potential near boundaries between sunlit and shadowed regions.</a> Geophys. Res. Lett. 34 (16), L16104 (2007).</li><li>Ding, N., Wang, J., Polansky, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Measurement+of+dust+charging+on+a+lunar+regolith+simulant+surface.">Measurement of dust charging on a lunar regolith simulant surface.</a> IEEE Trans. Plasma Sci. 41 (12), 3498-3504 (2013).</li><li>Sheridan, T. E., Hayes, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Charge+fluctuations+for+particles+on+a+surface+exposed+to+plasma.">Charge fluctuations for particles on a surface exposed to plasma.</a> Appl. Phys. Lett. 98 (9), 091501 (2011).</li><li>Heijmans, L. C. J., Nijdam, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dust+on+a+surface+in+a+plasma:+A+charge+simulation.">Dust on a surface in a plasma: A charge simulation.</a> Phys. Plasmas. 23 (6), 043703 (2016).</li><li>Wang, X., Schwan, J., Hsu, H. -. W., Gr&#252;n, E., Hor&#225;nyi, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dust+charging+and+transport+on+airless+planetary+bodies.">Dust charging and transport on airless planetary bodies.</a> Geophys. Res. Lett. 43 (12), 6103-6110 (2016).</li><li>Schwan, J., Wang, X., Hsu, H. -. W., Gr&#252;n, E., Hor&#225;nyi, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+charge+state+of+electrostatically+transported+dust+on+regolith+surfaces.">The charge state of electrostatically transported dust on regolith surfaces.</a> Geophys. Res. Lett. 44 (7), 3059-3065 (2017).</li><li>Allen, C. C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Martian+Regolith+Simulant+JSC-Mars-1.">Martian Regolith Simulant JSC-Mars-1.</a> The 29th Lunar and Planetary Science Conference. , (1998).</li><li>Martin, N. L. S., von Engel, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+reflection+of+slow+electrons+from+a+soot-covered+surface.">The reflection of slow electrons from a soot-covered surface.</a> J. Phys DAppl Phys. 10 (6), 863-868 (1977).</li><li>Halekas, J. S., Delory, G. T., Lin, R. P., Stubbs, T. J., Farrell, W. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Lunar+Prospector+measurements+of+secondary+electron+emission+from+lunar+regolith.">Lunar Prospector measurements of secondary electron emission from lunar regolith.</a> Planet. Space Sci. 57 (1), 78-82 (2009).</li><li>Wiese, R., Sushkov, V., Kersten, H., Ikkurthi, V. R., Schneider, R., Hippler, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Behavior+of+a+porous+particle+in+a+radiofrequency+plasma+under+pulsed+argon+ion+beam+bombardment.">Behavior of a porous particle in a radiofrequency plasma under pulsed argon ion beam bombardment.</a> New J. Phys. 12, 033036 (2010).</li><li>Richterov&#225;, I., N&#277;me&#269;ek, Z., Ber&#225;nek, M., &#352;afr&#225;nkov&#225;, J., Pavl&#367;, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Secondary+emission+from+non-spherical+dust+grains+with+rough+surfaces:+Applications+to+lunar+dust.">Secondary emission from non-spherical dust grains with rough surfaces: Applications to lunar dust.</a> Astrophys. J. 761 (2), 108 (2012).</li><li>Ma, Q., Matthews, L. S., Land, V., Hyde, T. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Charging+of+aggregate+grains+in+astrophysical+environments.">Charging of aggregate grains in astrophysical environments.</a> Astrophys. J. 763 (2), 77 (2013).</li><li>Dove, A., Hor&#225;nyi, M., Wang, X., Piquette, M., Poppe, A. R., Robertson, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Experimental+study+of+a+photoelectron+sheath.">Experimental study of a photoelectron sheath.</a> Phys. Plasmas. 19 (4), 043502 (2012).</li><li>Zimmerman, M. I., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Grain-scale+supercharging+and+breakdown+on+airless+regoliths.">Grain-scale supercharging and breakdown on airless regoliths.</a> J. Geophys. Res.-Planet. 121 (10), 2150-2165 (2016).</li><li>Wang, X., Pilewskie, J., Hsu, H. -. W., Hor&#225;nyi, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Plasma+potential+in+the+sheaths+of+electron-emitting+surfaces+in+space.">Plasma potential in the sheaths of electron-emitting surfaces in space.</a> Geophys. Res. Lett. 43 (12), 525-531 (2016).</li></ol>

For decades, the problem of electrostatic dust transport on the regolith of airless bodies remained an open question how regolith dust particles gain sufficiently large charges to become mobilized or lofted. Recent laboratory studies26,27 have fundamentally advanced the understanding of this problem.
Here, it is demonstrated three recently developed experiments to show dust charging and mobilization in thermal plasma with beam electron...

Airless planetary bodies, such as the Moon and asteroids, are covered with fine dust particles called regolith. These airless bodies, unlike Earth, are directly exposed to solar wind plasma and solar ultraviolet (UV) radiation, causing the regolith dust to be charged. These charged dust particles may therefore be mobilized, lofted, transported, or even ejected and lost from the surface due to electrostatic forces. The first suggested evidence of this electrostatic process was the so-called &#34;lunar horizon glow&#34;, a distinct glow above the western horizon observed shortly after sunset by Surveyor 5, 6, and 7 spacecraft five decades ago (Figure 1a)1,2,3. It has been hypothesized that this glow was caused by sunlight scattered off from electrostatically lofted dust particles (5 &#956;m radius) to a height &#60; 1 m above the surface near the lunar terminator1,2,3. Electrostatically released fine dust was also suggested to be responsible for the ray-like streamers reaching a high altitude reported by the Apollo astronauts4,5.
Ever since these Apollo observations, a number of observations over other airless bodies were also linked to the mechanisms of electrostatic dust mobilization or lofting, such as the radial spokes in the Saturn&#39;s rings6,7,8, the dust ponds on asteroid Eros (Figure 1b)9 and comet 67P10, the porous surfaces indicated from the main-belt asteroid spectra11, the unusually smooth surface of Saturn&#39;s icy moon Atlas12, and the regolith at the lunar swirls13. In addition, the degradation of the laser retroreflectors on the lunar surface may be also caused by the accumulation of electrostatically lofted dust14.
Laboratory studies have been largely motivated by these unusual space observations in order to understand the physical processes of dust charging and transport. Dust mobilization has been observed in various plasma conditions, in which dust particles are shed off from a glass sphere surface15,16, levitated in plasma sheaths17, and recorded to move on both conducting and insulating surfaces18,19,20,21. However, how dust particles gain large enough charges to be lofted or mobilized remained poorly understood. The measurements of the charges on individual dust particles on a smooth surface22 and the average charge density on a dusty surface23 immersed in plasmas show that the charges are far too small for dust particles to be lofted or mobilized.
In the prior theories16,24,25, the charging was only considered to occur on the top surface layer that is directly exposed to UV or plasma. Charges are often considered to be distributed uniformly over the entire dusty surface, i.e., each individual dust particle acquires the same amount of charge, described by the so-called &#34;shared charge model&#34;16. However, the charges calculated from this model are much smaller than the gravitational force alone. A charge fluctuation theory that accounts for the stochastic process of the fluxes of electrons and ions to the surface16,24 shows a temporal enhancement in the electrostatic force, but it remains small in comparison to the gravitational force.
In this paper, electrostatic dust lofting and mobilization is demonstrated using three recently developed experiments26, which are important for understanding dust transport on the regolith of airless planetary bodies. These experiments are performed in the conditions of thermal plasma with beam electrons, beam electrons only or UV radiation only. These experiments demonstrate the validity of the recently developed &#34;patched charge model&#34;26,27, in which microcavities formed between neighboring dust particles below the surface can re-absorb the emitted photo and/or secondary electrons, generating large negative charges on the surfaces of the neighboring dust particles. The repulsive forces between these negative charges can become large enough to mobilize or lift off the dust particles.

<table>
	<tbody>
		<tr>
			<td>Vacuum chamber</td>
			<td>Any</td>
			<td>NA</td>
			<td></td>
		</tr>
		<tr>
			<td>Vacuum electrode feedthrough</td>
			<td>Lesker</td>
			<td>EFT0113053</td>
			<td></td>
		</tr>
		<tr>
			<td>Tungsten filament (0.1 mm thick)</td>
			<td>Goodfellow</td>
			<td>W055250</td>
			<td>Thoriated</td>
		</tr>
		<tr>
			<td>Power supply #1 (0-8V, 3A)</td>
			<td>Agilent</td>
			<td>E3610A</td>
			<td>Or equivalent</td>
		</tr>
		<tr>
			<td>Power supply #2 (0-140V, 0.5A)</td>
			<td>Agilent</td>
			<td>E3612A</td>
			<td>Or equivalent</td>
		</tr>
		<tr>
			<td>UV lamp</td>
			<td>Osram</td>
			<td>XERADEX L40/120/SB-SX48/KF50HV</td>
			<td>Or equivalent</td>
		</tr>
		<tr>
			<td>Dust sample</td>
			<td>Any</td>
			<td>Mars or Lunar simulants or other types</td>
			<td>Irregularly-shaped, sieved, insulating</td>
		</tr>
		<tr>
			<td>Insulating plate</td>
			<td>Any</td>
			<td>NA</td>
			<td>Thickness &#62; 1 cm</td>
		</tr>
		<tr>
			<td>Rubber sheet</td>
			<td>Any</td>
			<td>NA</td>
			<td>Thickness &#62; 1 mm</td>
		</tr>
		<tr>
			<td>Metal plate</td>
			<td>Any</td>
			<td>NA</td>
			<td></td>
		</tr>
		<tr>
			<td>Ceramic stands</td>
			<td>McMaster</td>
			<td>94335A130</td>
			<td>1/2&#34; diameter</td>
		</tr>
		<tr>
			<td>Video camera (consumer)</td>
			<td>Panasonic</td>
			<td>HC-VX870</td>
			<td>Or equivalent</td>
		</tr>
		<tr>
			<td>Video camera (high-speed)</td>
			<td>Phantom</td>
			<td>V2512</td>
			<td>&#62; 1000 fps</td>
		</tr>
		<tr>
			<td>LED lamp</td>
			<td>Any</td>
			<td>NA</td>
			<td>&#62; 500W Tungsten Equivalent</td>
		</tr>
	</tbody>
</table>

experimental methods of dust charging and mobilization on surfaces with exposure to ultraviolet radiation or plasmas

Electrostatic dust transport has been hypothesized to explain a number of observations of unusual planetary phenomena. Here, it is demonstrated using three recently developed experiments in which dust particles are exposed to thermal plasma with beam electrons, beam electrons only, or ultraviolet (UV) radiation only. The UV light source has a narrow bandwidth in wavelength centered at 172 nm. The beam electrons with the energy of 120 eV are created with a negatively biased hot filament. When the vacuum chamber is filled with the argon gas, a thermal plasma is created in addition to the electron beam. Insulating dust particles of a few tens of microns in diameter are used in the experiments. Dust particles are recorded to be lofted to a height up to a few centimeters with a launch speed up to 1 m/s. These experiments demonstrate that photo and/or secondary electron emission from a dusty surface changes the charging mechanism of dust particles. According to the recently developed &#34;patched charge model&#34;, the emitted electrons can be re-absorbed inside microcavities between neighboring dust particles below the surface, causing the accumulation of enhanced negative charges on the surrounding dust particles. The repulsive forces between these negatively charged particles may be large enough to mobilize and lift them off the surface. These experiments present the advanced understanding of dust charging and transport on dusty surfaces, and laid a foundation for future investigations of its role in the surface evolution of airless planetary bodies.

A set of experiments were performed using the top or bottom filaments. With the top filament setup, the hopping of the dust particles was recorded (Figure 3a). In contrast, the dust particles remained at rest when using the bottom filament. It has been measured that the vertical electric field at the surface was approximately same (16 V/cm) in both experiments under the conditions described in Protocol step 226. These results indicate ...

Watch this Scientific Journal Video about Experimental Methods of Dust Charging and Mobilization on Surfaces with Exposure to Ultraviolet Radiation or Plasmas at JoVE.com

Experimental Methods of Dust Charging and Mobilization on Surfaces with Exposure to Ultraviolet Radiation or Plasmas

Dust charging and mobilization is demonstrated in three experiments with exposure to thermal plasma with beam electrons, beam electrons only, or ultraviolet (UV) radiation only. These experiments present the advanced understanding of electrostatic dust transport and its role in shaping the surfaces of airless planetary bodies.

Electrostatic dust transport has been hypothesized to explain a number of observations of unusual planetary phenomena. Here, it is demonstrated using ...

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Experimental System of Solar Adsorption Refrigeration with Concentrated Collector

To improve the performance of solar adsorption refrigeration, an experimental system with a solar concentration collector was set up and investigated. The ...

Adherence of Bacteria to Plant Surfaces Measured in the Laboratory

This manuscript describes a method to measure bacterial binding to axenic plant surfaces in the light microscope and through the use of viable cell ...

Preparation of DMMTAV and DMDTAV Using DMAV for Environmental Applications: Synthesis, Purification, and Confirmation

Preparation of DMMTAV and DMDTAV Using DMAV for Environmental Applications: Synthesis, Purification, and Confirmation

Dimethylated thioarsenicals such as dimethylmonothioarsinic acid (DMMTAV) and dimethyldithioarsinic acid (DMDTAV), which are produced by the metabolic ...