Abstract: A piezoelectric-photovoltaic hybrid structure is described, having a plurality of superposed layers including a photovoltaic layer and a piezoelectric substrate. A method of forming such a structure is also described, including the steps of providing a piezoelectric substrate and superposing a photovoltaic layer over the substrate. A power conversion system is described, comprising such a hybrid structure with a first circuit connected to the piezoelectric substrate and a second circuit connected to the photovoltaic layer. Also discussed is a method of generating, storing, distributing, or consuming electrical energy, involving the use of such a system in connection with a distribution circuit or network, electrical load, or energy storage device. A further power conversion system is described where the piezoelectric and photovoltaic circuits are connected to a single, or a respective, DC-DC converter. A set of such power conversion systems may be connected in series at their output terminals.

Abstract: Provided is a method for measurement of a change in environment at a sensor. The sensor has: a first layer formed of a piezoelectric material; a second layer formed adjacent the first layer and acoustically coupled with the first layer; and electrodes disposed to apply a driving signal to the first layer to generate bulk acoustic waves. The temperature coefficient of frequency of the first layer is different to that of the second layer. In the method, a first layer resonant frequency associated with the first layer and a combination resonant frequency associated with a combination of the first and second layers are detected. A shift in one or both of the first layer resonant frequency and the combination resonant frequency is detected. A portion of the shift caused by a temperature change at the sensor is identified. Another portion of the shift caused by an environmental change at the sensor other than the temperature change is identified.

Abstract: A piezoelectric polymer element such as a fiber or film is described, having a solid cross-section and a substantially homogeneous composition. A method of forming such a piezoelectric polymer element is also described. The method has the steps of extruding a polymer material and concurrently poling a region of the extruded material. Apparatus for forming such a piezoelectric polymer element is also described that comprises an extruder for extruding a polymer element from a granular feed and a pair of electrodes for applying an electric field across a region of the element concurrently with its extrusion. Also described is a piezoelectric construct having such piezoelectric polymer elements interposed between two conductive layers. A system for converting mechanical energy into electrical energy is described in which each of the piezoelectric construct's two conductive layers is connected to a respective terminal of a rectifying circuit.

Abstract: A polysaccharide fibre useful in biomedical applications such as wound management is made as a bicomponent fibre with alginate and psyllium polymers. An antimicrobial silver salt may be incorporated. The fibre may be made by extruding an aqueous mixture of alkaline-solubilised psyllium and sodium alginate into a calcium chloride bath.

Abstract: A piezoelectric polymer element such as a fibre or film is described, having a solid cross-section and a substantially homogeneous composition. A method of forming such a piezoelectric polymer element is also described. The method has the steps of extruding a polymer material and concurrently poling a region of the extruded material. Apparatus for forming such a piezoelectric polymer element is also described that comprises an extruder for extruding a polymer element from a granular feed and a pair of electrodes for applying an electric field across a region of the element concurrently with its extrusion. Also described is a piezoelectric construct having such piezoelectric polymer elements interposed between two conductive layers. A system for converting mechanical energy into electrical energy is described in which each of the piezoelectric construct's two conductive layers is connected to a respective terminal of a rectifying circuit.

Abstract: There are provided composite fibers of alginate and chitosan. Also provided are fiber materials methods of producing composite fibers or films and composite films. In one embodiment there is provided a composite fiber of alginate and chitosan suitable for use in wound management products, wherein chitosan polymer is bonded to alginate polymer along the length of the fiber.

Abstract: A piezoelectric-photovoltaic hybrid structure is described, having a plurality of superposed layers including a photo voltaic layer and a piezoelectric substrate. A method of forming such a structure is also described, including the steps of providing a piezoelectric substrate and superposing a photovoltaic layer over the substrate. A power conversion system is described, comprising such a hybrid structure with a first circuit connected to the piezoelectric substrate and a second circuit connected to the photovoltaic layer. Also discussed is a method of generating, storing, distributing, or consuming electrical energy, involving the use of such a system in connection with a distribution circuit or network, electrical load, or energy storage device. A further power conversion system is described where the piezoelectric and photovoltaic circuits are connected to a single, or a respective, DC-DC converter. A set of such power conversion systems may be connected in series at their output terminals.

Abstract: An auxetic polymeric material is manufactured in a filamentary or fibrous form. The auxetic polymeric material has a negative Poisson ratio so that it has the property of expanding or contracting transversely to a direction in which it is extended or compressed. The process for forming the material involves cohering and extruding heated polymer powder so that the cohesion and extrusion is effected with spinning to produce auxetic filaments. Typically, the power is heated to a temperature sufficient to allow some degree of surface melting yet not high enough to enable bulk melting.