A method for forming a geomembrane liner testable for leaks by securing adjacent panels together with the conductivity of the lower surface of an overlying panel broken along a line adjacent the panel overlapping edge, and the overlapping edges sealed along the line. A heat welder has slots for the overlapping panel edges, with a heated wedge between the slots and having a projection to break the conductivity of the overlying panel bottom surface as it passes the wedge. The slots merge to press the liner edges together to heat weld them along the line of broken conductivity as the welder is moved along the panel edges.

A method of making a wind turbine blade (10) having a metallic lightning receptor (110) is described. The method comprises configuring a wind turbine blade (10) mold assembly (100) such that a clearance region (120) is defined between a mold surface (116) of at least one mold half (112, 114) and a majority of a metallic lightning receptor component (110) when the mold assembly (100) is closed, such that contact between that mold half (112, 114) and the metallic lightning receptor component (110) is substantially avoided. In certain embodiments of the invention, one or both mold halves (112, 114) are truncated such that the metallic lightning receptor component (110) projects from the mold (100) when the mold (100) is closed.

A stimulation or recording electrode with varying impedances includes a plurality of layers that are compressed together with varying compressions forces, with at least a first compression force used at the perimeter of the electrode and a second compression force used towards the center of the electrode, with the first force being lesser than the second force, thereby creating a greater measured impedance at the perimeter of the electrode than at the center of the electrode.

A composite structure and methods of forming composite structures are provided. A composite structure comprises a first composite part; a second composite part welded to the first composite part at a joint; and the joint between the first composite part and the second composite part comprising doped fibers.

A composite strip which extends in a main direction between first and second ends and which comprises a main strip comprising first fibres embedded in a matrix. The first fibres are made of carbon, an electrically conducting material, and the matrix is made up of at least one polymer. The composite strip further comprises a junction layer formed of an electrically conducting junction material. The junction layer is placed on the main strip.

Multi-layered articles or products comprising layers of filled polymer compositions, methods of making and applications or uses thereof.

A method of forming shaped articles by welding.

A device for positioning in the body of an animal, the device comprising a first portion and a second portion that may be positioned in contact with one other, the first portion and the second portion each comprising a biocompatible conductive thermoplastic material, such that when the device is positioned in the body of an animal and electric current flows from the first portion to the second portion, heat is generated by electrical resistance at the point of contact between the first portion and the second portion so as to melt regions of the first portion and the second portion, and when the electric current is thereafter terminated, the melted regions of the first portion and the second portion re-solidify so that a weld is formed between the first portion and the second portion.

A device for joining a first component to be welded to a second component to be welded, the joining device having at least one electrically conductive, resistive heating film which comprises a central connection portion and two lateral electrical connection portions. The joining device comprises at least one first electrical insulation member which is positioned in contact with the first face of the heating film, and at least one second electrical insulation member which is positioned in contact with the second face of the heating film, the two electrical insulation members being configured to allow the transfer of heat and to prevent the flow of electric current between the heating film and each component to be welded.

An apparatus for forming a weld between a first portion of a biocompatible conductive thermoplastic material and a second portion of a biocompatible conductive thermoplastic material comprises a first electrode, a second electrode, and a structure for holding said first and second electrodes in opposition to one other with a space therebetween for receiving said first portion and said second portion in contact with one another. The structure is electrically non-conductive and an electrical circuit comprising a power source and a switch arranged such that closure of said switch applies a voltage potential across said first electrode and said second electrode so as to generate heat via electrical resistance, the heat being sufficient to melt regions of said first and second portions.