9328 results about "Electric potential" patented technology

A method for determining the concentration of a reduced (or oxidised) form of a redox species in an electrochemical cell of the kind comprising a working electrode and a counter electrode spaced from the working electrode by a predetermined distance, said method comprising the steps of: (1) applying an electric potential difference between the electrodes; (2) selecting the potential of the working electrode such that the rate of electro-oxidation of the reduced form (or electro-reduction of the oxidised form) of the species is diffusion controlled, (3) selecting the spacing between the working electrode and the counter electrode so that reaction products from the counter electrode arrive at the working electrode; (4) determining current as a function of time after application of the potential and prior to achievement of a steady state; (5) estimating the magnitude of the steady state current, and (6) obtaining from the change in current with time and the magnitude of the steady state current, a value indicative of the diffusion coefficient and/or of the concentration of the reduced form (or the oxidised form) of the species. Also disclosed is an apparatus for determining the concentration of a redox species in an electrochemical cell comprising: an electrochemical cell having a working electrode and a counter (or counter/reference) electrode, means for applying and electric potential difference between said electrodes, means for measuring the change in current with time, and characterised in that the working electrode is spaced from the counter electrode by less than 500 mum.

The present invention is directed to a gas line electron beam exciter, gas line electron beam excitation system and method for exciting a gas using an electron beam exciter. The electron beam exciter generally comprises a variable density electron source for generating a cloud of electrons in an electron chamber and a variable energy electron extractor for accelerating electrons from the electron chamber as an electron beam and into an effluent stream for fluorescing species in the effluent. The electron density of the electron beam is variably controlled by adjusting the excitation power applied to the variable density electron source. The electrons in the electron chamber reside at a reference electrical potential of the chamber, typically near ground electrical potential. The electron energy of the electron beam is variably controlled by adjusting an electrical potential across the variable energy electron extractor, which energizes the electrons through an extraction hole of the chamber and toward the extractor. The greater the difference in the electrical potential between the electron extractor and the electron source, the higher the energy imparted to the electrons in the electron beam. The excitation power applied to the electron source can be adjusted independently from the electron energy of the electron beam, thereby altering the electron density of the electron beam without changing the energy level of the electrons of the electron beam.

A minimally-invasive analyte detecting device and method for using the same. The system and method employ a device having an active electrode optionally coated with a substance, and a counter-electrode that is configured at least partially surround the active electrode. The configuration of the auxiliary electrode and active electrode improves the current flow through the device and increases the sensitivity of the device. When the device is placed against the patient's skin, the active electrode is adapted to enter through the stratum corneum of a patient to a depth less than a depth in the dermis at which nerve endings reside. An electric potential is applied to the active electrode and the analyte level is determined based on the amount of current or charge flowing through the device.

Method and apparatus for determining the instantaneous location, the orientation of an object moving through a three-dimensional space by applying to the object a coil assembly including a plurality of sensor coils (20) having axes of known orientation with respect to each other including components in the three orthogonal planes; generating a time-varying, three-dimensional magnetic field gradient having known instantaneous values of magnitude and direction; applying the magnetic field gradient to the space, and object moving therethrough to induce electrical potentials in the sensor coils; measuring the instantaneous values of the induced electrical potentials generated in the sensor coils; processing the measured instantaneous values generated in the sensor coils together with the known magnitude, direction of the generated magnetic field gradient, the known relative orientation of the sensor coils in the coil assembly to compute the instantaneous location, orientation of the object within the space.

A display device for modulating light intensity in response to programmed data output. Tapered cells within a base material containing a fluid within which are contained electrostatically responsive particles. Electrodes couple data signals to opposing portions of the cells, whereupon the position of the particles is modulated in response to the electric potential applied to said electrodes. A number of electronic ink displays, systems and method aspects are described.

An electro-optical device is provided having a pixel portion with a novel structure, and in which display irregularities such as crosstalk, which develop due to a drop in voltage caused by the wiring resistance of electric current supply lines in an electro-optical device, are improved upon. Attention is drawn to the fact that during a period in which write in of a signal to a pixel from a signal line is not performed, a signal is not input to a source signal line and to a gate signal line, but are at a fixed electric potential. An electric current supply line and a source signal line, or an electric current supply line and a gate signal line, are connected through a switching transistor. A signal is input to a connection control line during a sustain period, and the connection transistor is made conductive. The source signal line or the gate signal line is therefore utilized as a pathway for supplying electric current to the EL element.

A device positionable in a cavity of a bodily organ (e.g., a heart) may discriminate between fluid (e.g., blood) and non-fluid tissue (e.g., wall of heart) to provide information or a mapping indicative of a position and/or orientation of the device in the cavity. Discrimination may be based on flow, or some other characteristic, for example electrical permittivity or force. The device may selectively ablate portions of the non-fluid tissue based on the information or mapping. The device may detect characteristics (e.g., electrical potentials) indicative of whether ablation was successful. The device may include a plurality of transducers, intravascularly guided in an unexpanded configuration and positioned proximate the non-fluid tissue in an expanded configuration. Expansion mechanism may include helical member(s) or inflatable member(s).

In a first aspect of the invention, an image display device, in which one or more groups of particles or liquid powders are sealed between opposed two substrates, at least one of two substrates being transparent, and, in which the particles or the liquid powders, to which an electrostatic field produced by two groups of electrodes having different potentials is applied, are made to move so as to display an image, has a construction such that a member for transmitting a signal, which is applied to circuits for an image display, is provided to the substrate by means of an anisotropic conductive film and members such as the electrode are provided to a substrate opposed to a transparent substrate. In second to sixth aspects of the invention, an image display device has a construction such that the electrode is arranged to a surface of the substrate through a transparent elastic member, or, an anti-reflection layer is arranged, or, a connection operation between two substrates through a partition wall is optimized.

A series of microactuators for manipulating small quantities of liquids, and methods of using these for manipulating liquids, are disclosed. The microactuators are based on the phenomenon of electrowetting and contain no moving parts. The force acting on the liquid is a potential-dependent gradient of adhesion energy between the liquid and a solid insulating surface.

An electrochemical mirror includes a transparent first electrode and a second electrode. An electrolytic solution, disposed between the first and second electrodes, contains ions of a metal which can electrodeposit on the electrodes. A negative electrical potential applied to the first electrode causes deposited metal to be dissolved from the second electrode into the electrolytic solution and to be electrodeposited from the solution onto the first electrode, thereby affecting the reflectivity of the mirror for electromagnetic radiation. A surface modification layer applied to the first electrode ensures that the electrodeposit is substantially uniform, resulting in a mirror layer which increases the reflectivity of the mirror. A positive electrical potential applied to the first electrode causes deposited metal to be dissolved from the first electrode and electrodeposited from the solution onto the second electrode, thereby decreasing the reflectivity of the mirror.

A petroleum well having a well casing, a production tubing, a source of time-varying current, a downhole chemical injection device, and a downhole induction choke. The casing extends within a wellbore of the well. The tubing extends within the casing. The current source is located at the surface. The current source is electrically connected to, and adapted to output a time-varying current into, the tubing and/or the casing, which act as electrical conductors for providing downhole power and/or communications. The injection device having a communications and control module, a chemical container, and an electrically controllable chemical injector. The communications and control module is electrically connected to the tubing and/or the casing. The chemical injector is electrically connected to the communications and control module, and is in fluid communication with the chemical container. The downhole induction choke is located about a portion of the tubing and/or the casing. The chemical injector is electrically connected to the communications and control module, and is in fluid communication with the chemical container. The downhole induction choke is located about a portion of the tubing and/or the casing. The induction choke is adapted to route part of the electrical current through the communications and control module by creating a voltage potential between one side of the induction choke and another side of the induction choke. The communications and control module is electrically connected across the voltage potential. Also, a method is provided for controllably injecting a chemical into the well downhole, which may be used to: improve lift efficiency with a foaming agent, prevent deposition of solids with a paraffin solvent, improve a flow characteristic of the flow stream with a surfactant, prevent corrosion with a corrosion inhibitor, and/or prevent scaling with scale preventers.

A gas-lift petroleum well and method for producing petroleum products using downhole pressurized gas to provide lift. The gas-lift well having a well casing, a production tubing, a packer, and a gas-lift valve. The well casing extends within a wellbore of the well, and the wellbore extends through oil and gas zones. The production tubing extends within the casing. The tubing having an opening formed therein, which is in fluid communication with an oil zone. The packer is located downhole in the casing and coupled to the tubing. The packer can have an electrically controllable packer valve, which is adapted to control a flow of downhole pressurized gas from one side of the packer to another. The downhole pressurized gas is provided by a gas zone that the wellbore passes through. The downhole gas-lift valve is coupled to the tubing and is adapted to control a flow of downhole pressurized gas into oil in the tubing for lifting the oil. The gas-lift valve can be an electrically controllable valve. The tubing and casing are used as electrical conductors for supplying power and/or communications downhole. The current in the tubing is routed using a ferromagnetic induction choke to create a voltage potential, which provides electrical power to downhole electrical devices. Also, there may be a bypass passageway to route downhole gas to gas-lift valves. There may also be downhole sensors to measure physical quantities (e.g., pressure). Such measurements can be used for feedback control of downhole electrically controllable valves.

A low cost, efficient, and rapid means for transferring energy or balancing charge among multiple, series connected batteries, capacitors, photovoltaic cells, fuel cells, and other types of energy source or storage devices is provided. Modules that transfer energy by moving charge from one or more series connected energy devices directly to one or more other energy devices in the string are disclosed. The modules utilize steering circuits comprised of switches and rectifiers, and energy storage elements such as inductors and transformers, to transfer energy between multiple energy devices in the string. The modules may be used in combination with string charging devices and loads. The modules provide a means to balance charge or potential of the energy devices, which is known to provide benefits of increased life and capacity.

A wireless biopotential monitoring system composed of a wireless electrode module which can be attached to a disposable electrode strip. Such a device can be conveniently affixed to a patient's skin and will transmit the physiological signals to a remote receiver where the signals can be monitored by a clinician. The device is powered by a fuel-air battery. The device would remain packaged in an airtight package until it needs to be applied at which time either the wounded soldier would apply the device himself/herself or it would be applied by another soldier or corpsman. The device would begin to measure brainwave activity, heart rate, and dissolved oxygen level. The device would also identify the wounded soldier's location using the onboard GPS receiver. The physiologic data along with the soldier's position would then be transmitted to a remote receiver.

A pixel circuit includes a driver element that is supplied with a potential from a data line. The driver element controls a value of current passing through an electric light emitting element. Upon obtaining a threshold voltage, a conductive member connected to the electric light emitting element is made to be a floating state to cause the driver element to become on-state, variations in the potential of the conductive member caused by charges passing through the driver element to flow into the conductive member are detected by a threshold voltage detector to obtain the threshold voltage of the driver element.