Microporous polypropylene membrane filters are modified with a cationic surfactant, dimethyldioctadecylammoniumbromide (DDAB), to create a charged surface. Negatively charged nanoparticles can then be filtered by utilizing the electrostatic interaction between the charged particles and the polar heads of the surfactants adsorbed on the filters. The study focuses on particle adsorption and parti...

Any charged particle moving faster than light through a medium emits Cherenkov radiation. We show that charged particles moving faster than light through the vacuum emit Cherenkov radiation. How can a particle move faster than light? The weak speed of a charged particle can exceed the speed of light. By definition, the weak velocity ^v&w is ^C f inuvuC in&/^C f inuC in&, where v is the velocity...

Any charged particle moving faster than light through a medium emits Cherenkov radiation. We show that charged particles moving faster than light through the vacuum emit Cherenkov radiation. How can a particle move faster than light? The weak speed of a charged particle can exceed the speed of light. By definition, the weak velocity v w is Ψ f in |v|Ψ in /Ψ f in |Ψ in , where v is the velocity ...

The earth's magnetotail is characterized by stretched magnetic field lines. Energetic particles are effectively scattered due to the field-line curvature, which then leads isotropization of energetic particle distributions and precipitation atmosphere. Measurements at low-altitude spacecrafts are, thus, often used remotely probe current sheet configuration. This configuration may include spatia...