Abstract: An implantable stent comprises a tubular member having an interior surface and an exterior surface, with a region of at least one of the surfaces being hydrophobic. The region is provided with an array of microstructures or nanostructures that covers first portions of the surface but leaves second portions exposed in the interstices of the array. These structures cause the region to have a dynamically controllable hydrophobicity. In one embodiment, a control device, which is affixed to the tubular member, varies the hydrophobicity of the region. In another embodiment, which is particularly applicable to the delivery of a medicinal substance to fluids in body vessels, the stent also includes such a medicinal substance that adheres to the exposed portions until the control device alters the hydrophobicity of the region and causes the substance to be released into a body fluid in contact with the stent. Various ways to load the stent are described.

Abstract: A method and apparatus is disclosed wherein the flow resistance of a droplet disposed on a nanostructured or microstructured surface is controlled. A closed-cell feature is used in a way such that, when the pressure of at least a first fluid within one or more of the cells of said surface is decreased to or below a desired level, a droplet disposed on that surface is caused to at least partially penetrate the surface. In another illustrative embodiment, the pressure within one or more of the cells is increased to or above a desired level in a way such that the droplet of liquid is returned at least partially to its original, unpenetrated position. In yet another embodiment, a closed-cell structure feature pattern is used to prevent penetration of the nanostructured or microstructured surface, even when the pressure of the fluid disposed on the surface is relatively high.

Abstract: A method and apparatus is disclosed wherein the flow resistance of a droplet disposed on a nanostructured or microstructured surface is controlled. A closed-cell feature is used in a way such that, when the pressure of at least a first fluid within one or more of the cells of said surface is decreased to or below a desired level, a droplet disposed on that surface is caused to at least partially penetrate the surface. In another illustrative embodiment, the pressure within one or more of the cells is increased to or above a desired level in a way such that the droplet of liquid is returned at least partially to its original, unpenetrated position. In yet another embodiment, a closed-cell structure feature pattern is used to prevent penetration of the nanostructured or microstructured surface, even when the pressure of the fluid disposed on the surface is relatively high.

Abstract: A method and apparatus is disclosed wherein the flow resistance of a droplet disposed on a nanostructured or microstructured surface is controlled. A closed-cell feature is used in a way such that, when the pressure of at least a first fluid within one or more of the cells of said surface is decreased to or below a desired level, a droplet disposed on that surface is caused to at least partially penetrate the surface. In another illustrative embodiment, the pressure within one or more of the cells is increased to or above a desired level in a way such that the droplet of liquid is returned at least partially to its original, unpenetrated position. In yet another embodiment, a closed-cell structure feature pattern is used to prevent penetration of the nanostructured or microstructured surface, even when the pressure of the fluid disposed on the surface is relatively high.

Abstract: A battery includes a plurality of closed cells disposed in a predetermined feature pattern on at least a first surface of an electrode. Each of the closed cells has an inner surface. The battery also includes a plurality of cell electrodes. Each of the cell electrodes is disposed along a portion of the inner surface of a respective one of the closed cells in the plurality of closed cells.

Abstract: A battery having a nanostructured battery electrode is disclosed wherein it is possible to reverse the contact of the electrolyte with the battery electrode and, thus, to return a battery to a reserve state after it has been used to generate current. In order to achieve this reversibility, the nanostructures on the battery electrode comprise a plurality of closed cells and the pressure within the enclosed cells is varied. In a first embodiment, the pressure is varied by varying the temperature of a fluid within the cells by, for example, applying a voltage to electrodes disposed within said cells. In a second illustrative embodiment, once the battery has been fully discharged, the battery is recharged and then the electrolyte fluid is expelled from the cells in a way such that it is no longer in contact with the battery electrode.

Abstract: A battery having an electrode with at least one nanostructured surface is disclosed wherein the nanostructured surface is divided into cells and is disposed in a way such that an electrolyte fluid of the battery is prevented from contacting the portion of electrode associated with each cell. When a voltage is passed over the nanostructured surface associated with a particular cell, the electrolyte fluid is caused to penetrate the nanostructured surface of that cell and to contact the electrode, thus activating the portion of the battery associated with that cell. The current/voltage generated by the battery is controlled by selectively activating only a portion of the cells. Multiple cells can be active simultaneously to produce the desired voltage. The more cells that are active, the higher the current/voltage and the lower the overall life of the battery. The life of the battery can be extended by activating fewer cells simultaneously.

Abstract: A battery having a nanostructured battery electrode is disclosed wherein it is possible to reverse the contact of the electrolyte with the battery electrode and, thus, to return a battery to a reserve state after it has been used to generate current. In order to achieve this reversibility, the nanostructures on the battery electrode comprise a plurality of closed cells and the pressure within the enclosed cells is varied. In a first embodiment, the pressure is varied by varying the temperature of a fluid within the cells by, for example, applying a voltage to electrodes disposed within said cells. In a second illustrative embodiment, once the battery has been fully discharged, the battery is recharged and then the electrolyte fluid is expelled from the cells in a way such that it is no longer in contact with the battery electrode.

Abstract: A cell-array battery is disclosed having end-of-life cells that can be activated at the end of a battery's life to, illustratively, neutralize the toxic chemicals inside the battery. In one embodiment, neutralization of the electrolyte in the battery is achieved through immobilization of the electrolyte at the end of the life of the battery by, for example, a vitrification process. Using electrowetting techniques, the electrolyte is made to contact a neutralizing substance between the nanostructures in one or more end-of-life cells, thus causing a reaction that results in the electrolyte becoming immobilized by, for example, a polymer substance. In a second illustrative embodiment, when the electrolyte contacts the substance between the nanostructures in one or more end-of-life cells, the chemical composition of the electrolyte is changed into a less toxic chemical compound, thus neutralizing the electrolyte.

Abstract: A cell-array battery is disclosed having end-of-life cells that can be activated at the end of a battery's life to, illustratively, neutralize the toxic chemicals inside the battery. In one embodiment, neutralization of the electrolyte in the battery is achieved through immobilization of the electrolyte at the end of the life of the battery by, for example, a vitrification process. Using electrowetting techniques, the electrolyte is made to contact a neutralizing substance between the nanostructures in one or more end-of-life cells, thus causing a reaction that results in the electrolyte becoming immobilized by, for example, a polymer substance. In a second illustrative embodiment, when the electrolyte contacts the substance between the nanostructures in one or more end-of-life cells, the chemical composition of the electrolyte is changed into a less toxic chemical compound, thus neutralizing the electrolyte.

Abstract: A method and apparatus is disclosed wherein nanostructures or microstructures are disposed on a surface of a body (such as a submersible vehicle) that is adapted to move through a fluid, such as water. The nanostructures or microstructures are disposed on the surface in a way such that the contact between the surface and the fluid is reduced and, correspondingly, the friction between the surface and the fluid is reduced. In an illustrative embodiment, the surface is a surface on a submarine or other submersible vehicle (such as a torpedo). Illustratively, electrowetting principles are used to cause the fluid to at least partially penetrate the nanostructures or microstructures on the surface of the body in order to selectively create greater friction in a desired location of the surface. Such penetration may be used, for example, to create drag that alters the direction or speed of travel of the body.

Abstract: A method and apparatus is disclosed wherein nanostructures or microstructures are disposed on a surface of a body (such as a submersible vehicle) that is adapted to move through a fluid, such as water. The nanostructures or microstructures are disposed on the surface in a way such that the contact between the surface and the fluid is reduced and, correspondingly, the friction between the surface and the fluid is reduced. In an illustrative embodiment, the surface is a surface on a submarine or other submersible vehicle (such as a torpedo). Illustratively, electrowetting principles are used to cause the fluid to at least partially penetrate the nanostructures or microstructures on the surface of the body in order to selectively create greater friction in a desired location of the surface. Such penetration may be used, for example, to create drag that alters the direction or speed of travel of the body.

Abstract: A nanostructured substrate is disclosed having a plurality of substrate openings disposed between the nanostructures on the substrate. When a desired fluid comes into contact with the substrate, at least a portion of the fluid is allowed to pass through at least one of the openings. In a first embodiment, the fluid is caused to pass through the openings by causing the fluid to penetrate the nanostructures. In a second embodiment, the substrate is a flexible substrate so that when a mechanical force is applied to the substrate, such as a bending or stretching force, the distance between nanoposts or the diameter of nanocells on the substrate increases and the liquid penetrates the nanostructures. In another embodiment, a first fluid, such as water, is prevented from penetrating the nanostructures on the substrate while a second fluid is permitted to pass through the substrate via the openings in the substrate.

Abstract: A method and apparatus are disclosed wherein a battery comprises an electrode having at least one nanostructured surface. The nanostructured surface is disposed in a way such that an electrolyte fluid of the battery is prevented from contacting the electrode, thus preventing discharge of the battery when the battery is not in use. When a voltage is passed over the nanostructured surface, the electrolyte fluid is caused to penetrate the nanostructured surface and to contact the electrode, thus activating the battery. In one illustrative embodiment, the battery is an integrated part of an electronics package. In another embodiment, the battery is manufactured as a separate device and is then brought into contact with the electronics package. In yet another embodiment, the electronics package and an attached battery are disposed in a projectile that is used as a military targeting device.

Abstract: A method and apparatus is disclosed wherein nanostructures or microstructures are disposed on a surface of a body (such as a submersible vehicle) that is adapted to move through a fluid, such as water. The nanostructures or microstructures are disposed on the surface in a way such that the contact between the surface and the fluid is reduced and, correspondingly, the friction between the surface and the fluid is reduced. In an illustrative embodiment, the surface is a surface on a submarine or other submersible vehicle (such as a torpedo). Illustratively, electrowetting principles are used to cause the fluid to at least partially penetrate the nanostructures or microstructures on the surface of the body in order to selectively create greater friction in a desired location of the surface. Such penetration may be used, for example, to create drag that alters the direction or speed of travel of the body.

Abstract: A biological/chemical detector is disclosed that is capable of manipulating liquids, such as reagent droplets, without relying on microchannels. In a first embodiment, fluid flow is passed through the detector, thus causing particles wholly or partially containing an illustrative chemical compound or biological species to be collected on the tips of nanostructures in the detector. A droplet of liquid is moved across the tips of the nanostructures, thus absorbing the particles into the liquid. The droplet is caused to penetrate the nanostructures in a desired location, thus causing the chemical compound or biological species in said liquid droplet to come into contact with, for example, a reagent. In another embodiment, a fluid flow is passed through the nanostructured surfaces of the detector such that the chemical compound and/or biological species are deposited between the nanoposts of a desired pixel.

Abstract: A liquid electrical switch is disclosed that uses a plurality of droplets of conducting liquid to form an electrical path. In a first embodiment, at least a first voltage differential is used to create a separation distance between two droplets. The droplets are illustratively contained within a housing and surrounded by an immiscible, insulating liquid. In this embodiment, the at least a first voltage differential draws at least a portion of at least one of the droplets away from a second droplet, thus preventing electrical current from flowing from the at least one droplet to the second droplet. In another embodiment, the at least a first voltage differential is changed in a way such that at least one liquid droplet is made to come into contact with a second droplet, thus creating an electrical path between the two droplets.

Abstract: A tunable microlens uses at least two layers of electrodes and a droplet of conducting liquid. Such a droplet, which forms the optics of the microlens, moves toward an electrode with a higher voltage relative to other electrodes in the microlens. When calibration of the microlens is desired, an equal and constant voltage is passed over the first layer of electrodes and a different, constant voltage is passed over the second layer of electrodes such that the droplet of conducting fluid is adjusted to a calibrated position.

Abstract: A tunable microlens uses at least two layers of electrodes and a droplet of conducting liquid. Such a droplet, which forms the optics of the microlens, moves toward an electrode with a higher voltage relative to other electrodes in the microlens. When calibration of the microlens is desired, an equal and constant voltage is passed over the first layer of electrodes and a different, constant voltage is passed over the second layer of electrodes, which may, for example, be disposed in a star-like pattern. A driving force relative to each electrode in the second layer results and is proportional to the length of the circumference of the droplet that intersects with each of the electrodes. This driving force reaches equilbrium, and hence the droplet reaches its nominal centered position relative to the second layer of electrodes, when the length of intersection of the circumference of the droplet with each of the electrodes in the second layer is equal.

Abstract: A tunable optical lens includes a solid refractive optical lens, a channel adjacent to the solid refractive optical lens, and an extended body of liquid. A portion of the body forms at least part of an aperture stop for the lens. The portion of the body forms a meniscus that protrudes from or into the channel. The liquid is light-absorbing in the visual spectrum and/or in the near-infrared spectrum.