Abstract: Planar electrodes include a carbon fiber cloth which is woven or braided from a plurality of PAN-derived carbon fibers and which is mounted in a frame. The frame is preferably made of an inert plastic material such as TEFLON, PVC, or DELRIN and the carbon fiber cloth is preferably affixed to the frame with metal strips and fasteners. The metal strips are preferably titanium or a noble metal and the fasteners are preferably made of the same metal as the strips. The metal strips form a low impedance electrical contact with the carbon fiber cloth and enable the electrode to be coupled to a wire lead or electrical contact for use in an electrochemical circuit. According to a second embodiment, the carbon fiber cloth is sandwiched between two metal frames. According to a third embodiment, the carbon fiber cloth is sandwiched between two plastic frames with conductive foil strips or titanium strips forming an electrical contact with the carbon fiber cloth.

Abstract: A carbon fiber electrode is coated with a noble metal oxide to create a noble metal oxide electrode with a very large surface area. According to a presently preferred embodiment, the noble metal oxide is iridium oxide. A method of making the electrode includes preparing a solution of iridium chloride and isopropyl alcohol, dipping a carbon fiber electrode into the solution, drying the electrode in the presence of nitrogen and heat, and heat treating the electrode in the presence of oxygen. An apparatus for removing nitrates from water includes an electrochemical flow cell through which the aqueous solution containing nitrates flows or a holding tank cell into which the solution is introduced and then released after processing, and an electrode system including an anodic iridium oxide coated carbon fiber electrode as described above, a carbon fiber cathodic electrode and a reference electrode.

Abstract: A Ag/AgCl electrode includes a rigid tube within which a Ag/AgCl conductor is mounted by epoxy. An insulated wire lead is coupled by a solder joint to the Ag/AgCl conductor. An optional plastic cap seals the upper end of the tube and the wire lead extends out of the upper end of the tube and through the plastic cap. A sodium chloride solution is provided in the lower end of the tube such that the conductor is bathed in the solution. The solution is maintained within the tube by a porous glass, ceramic, or polymeric plug which is press fit into the lower end of the tube. The lower end of the tube, including the plug, is coated with a water soluble non-toxic substance. The water soluble coating is preferably made from a concentrated solution of polyvinyl alcohol (PVA) in deionized or RO water which is preferably applied by dip coating and air drying.

Abstract: An apparatus for reducing nitrates in an aqueous solution includes an electrochemical cell having a container for containing the aqueous solution containing nitrates, a carbon fiber cathodic electrode, a carbon fiber anodic electrode, and a reference electrode immersed in the aqueous solution, and an electronic control circuit which impresses a voltage across the electrodes causing electrochemical reduction/oxidation reactions on the surfaces of the electrodes. The electrodes are at a potential such that nitrates are reduced to gaseous products, and further such that hydrogen, oxygen, chlorine, an other noxious substances are not produced. The cell may be a flow cell or a holding tank and apparatus of different size and capacity are disclosed. The apparatus is useful in reducing nitrates in any water system and is particularly useful in reducing nitrates in aquatic systems without harming aquatic life.

Abstract: An elongate endocardial lead is disclosed which includes at least one distal electrode for sensing electrical activity in, and delivering electrical pacing pulses to, a patient's malfunctioning heart, a plurality of proximal terminal pins for coupling the lead to a pacemaker device, and a distal pressure sensor for sensing haemodynamic pressure within the heart. The pressure sensor comprises an integrated circuit chip having a layer of piezo-resistive material and a non-conductive base member, with the layer of piezo-resistive material being carried by the base member and having a pressure sensing diaphragm area therein exposed to ambient pressure. The base member and layer of piezo-resistive material are constructed and arranged so as to form a hermetically sealed chamber therebetween, with the chamber being at substantially atmospheric pressure and being substantially coextensive with the pressure sensing diaphragm area.

Abstract: A metabolic-demand pacemaker in which the standby rate is a function of minute volume. Electrodes are placed in a blood vessel in the vicinity of the patient's pleural cavity, a known current field is established in the blood, and the impedance in the field is measured. The impedance is a function of the pleural pressure which, in turn, is a function of the patient's minute volume. The system also includes a mechanism for calibrating the standby rate to equal the nominal standby rate for a minute volume which equals a long-term average value, with the standby rate being changed in accordance with the deviation of the minute volume from the long-term average value.

Abstract: A device for sharpening skis having metal edges is disclosed. The device employs at least two spaced apart edge sharpening tools, such as files, which straddle the ski edges. Each file is connected to a constant torque device. In this manner the edge sharpening tools are automatically brought into continuous contact with the lateral surfaces of the metal edges of the ski with an equal and constant pressure which is not dependent on the user's skills. In preferred embodiments the side files are symmetrically mounted, for example on rotatable arms so that regardless of the lateral pressure applied by the user while sliding the tool longitudinally on the ski, a uniform sharpening and filing pressure is applied to the entire length of the ski edge. The device also provides a support and positioning function for one or more smoothing tool, such as a flat file, which extends transversely across the bottom of the ski as the device is moved longitudinally along the ski.