Abstract: An electrospinning method includes providing a nozzle fluidically coupled to a source of polymer ink and providing a substrate adjacent to the nozzle. A first voltage is applied to the nozzle to initiate electrospinning of the polymer ink onto the substrate, wherein the first voltage is within the range of about 400V to about 1000V. The voltage is then reduced to a second, lower voltage wherein the voltage is within the range of about 600V to about 150V.

Abstract: An electrospinning method includes providing a nozzle fluidically coupled to a source of polymer ink and providing a substrate adjacent to the nozzle. A first voltage is applied to the nozzle to initiate electrospinning of the polymer ink onto the substrate, wherein the first voltage is within the range of about 400V to about 1000V. The voltage is then reduced to a second, lower voltage wherein the voltage is within the range of about 600V to about 150V.

Abstract: Gas flows of modest velocities are generated when an organized ion flux in an electric field initiates an ion-driven wind of neutral molecules. When a needle in ambient air is electrically charged to a potential sufficient to produce a corona discharge near its tip, such a gas flow can be utilized downstream of a ring-shaped or other permeable earthed electrode. In view of the potential practical applications of such devices, as they represent blowers with no moving parts, a methodology for increasing their flow velocities includes exploitation of the divergence of electric field lines, avoidance of regions of high curvature on the second electrode, control of atmospheric humidity, and the use of linear arrays of stages, terminating in a converging nozzle. The design becomes particularly advantageous when implemented in mesoscale domains.

Abstract: Gas flows of modest velocities are generated when an organized ion flux in an electric field initiates an ion-driven wind of neutral molecules. When a needle in ambient air is electrically charged to a potential sufficient to produce a corona discharge near its tip, such a gas flow can be utilized downstream of a ring-shaped or other permeable earthed electrode. In view of the potential practical applications of such devices, as they represent blowers with no moving parts, a methodology for increasing their flow velocities includes exploitation of the divergence of electric field lines, avoidance of regions of high curvature on the second electrode, control of atmospheric humidity, and the use of linear arrays of stages, terminating in a converging nozzle. The design becomes particularly advantageous when implemented in mesoscale domains.

Abstract: A system for quantifying surface characteristics detects and quantifies characteristics of a surface of an object. For example, the system may quantify changes in surface roughness without contacting the specimen and without requiring precise temporal or spatial stability. The system may also quantify the evolution or progression of a particular characteristic of a surface, such as a defect, a slipband, a crack, a microcrack, a pit, a damage feature, corrosion, a contour change, an impact crater, a change in residual stress, and so on. The system may include an energy source, a detector section, and a process section. The energy source transmits a source signal to the surface of the object. The source signal is specularly reflected and/or scattered by the surface to yield one or more received signals. The detector section receives the received signal and, in turn, provides a detector signal indicative of the received signal.

Abstract: A miniature combustor comprising a combustion chamber having at least one critical dimension that is sub-centimeter. Combustion is confined within the chamber by injecting a liquid fuel as a film over substantially the entire area of the chamber walls. In a preferred embodiment, a swirl or vortex generator may be included at the entrance of the chamber to cause the in-flowing oxidizing gases to swirl within the chamber. The liquid fuel may be applied as a film through one or more orifices or a porous wall material, or may be applied by spraying the fuel on a surface within the chamber. The liquid fuel may be augmented with an inert liquid such as water.

Abstract: A system for quantifying surface characteristics detects and quantifies characteristics of a surface of an object. For example, the system may quantify changes in surface roughness without contacting the specimen and without requiring precise temporal or spatial stability. The system may also quantify the evolution or progression of a particular characteristic of a surface, such as a defect, a slipband, a crack, a microcrack, a pit, a damage feature, corrosion, a contour change, an impact crater, a change in residual stress, and so on. The system may include an energy source, a detector section, and a process section. The energy source transmits a source signal to the surface of the object. The source signal is specularly reflected and/or scattered by the surface to yield one or more received signals. The detector section receives the received signal and, in turn, provides a detector signal indicative of the received signal.

Abstract: A miniature combustor comprising a combustion chamber having at least one critical dimension that is sub-centimeter. Combustion is confined within the chamber by injecting a liquid fuel as a film over substantially the entire area of the chamber walls. In a preferred embodiment, a swirl or vortex generator may be included at the entrance of the chamber to cause the in-flowing oxidizing gases to swirl within the chamber. The liquid fuel may be applied as a film through one or more orifices or a porous wall material, or may be applied by spraying the fuel on a surface within the chamber. The liquid fuel may be augmented with an inert liquid such as water.

Abstract: A miniature combustor comprising a combustion chamber having at least one critical dimension that is sub-centimeter. Combustion is confined within the chamber by injecting a liquid fuel as a film over substantially the entire area of the chamber walls. In a preferred embodiment, a swirl or vortex generator may be included at the entrance of the chamber to cause the in-flowing oxidizing gases to swirl within the chamber. The liquid fuel may be applied as a film through one or more orifices or a porous wall material, or may be applied by spraying the fuel on a surface within the chamber. The liquid fuel may be augmented with an inert liquid such as water.