Abstract: Disclosed microreactors operate in an electrical discharge mode, such as a pulse mode, an arc mode or a corona discharge mode, and most preferably in a corona discharge mode. A microreactor may comprise multiple, simultaneously operating corona discharges. The microreactor typically has at least one feature measured on a millimeter scale. Certain disclosed microreactors comprised multiple reactor plates in a stack. Each plate comprised plural corona discharge electrodes positioned in series along each of plural corresponding microchannels. A method for using disclosed microreactors and systems comprising disclosed microreactors, such as for chemical transformations, fluid purifications, or both, also is disclosed.

Abstract: A system can comprise a screw and a nut, which are configured to move relative to each other. Each of the screw and the nut components can comprise one or more magnets configured to exert a repulsive force on one or more magnets of the other component as a result of the relative motion. Interactions between the one or more magnets of the screw and the one or more magnets of the nut can allow for conversion between linear motion and rotary motion. One or more tools can be used to aid in manufacturing the screw and/or the nut. In some embodiments additional components can aid in maintaining alignment of the screw and the nut.