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Showing papers on "Electrode array published in 1975"


Journal ArticleDOI
TL;DR: A technique is described which allows neurons to be voltage clamped with a single microelectrode, and the advantages of this circuit with respect to conventional bridge techniques are discussed.
Abstract: A technique is described which allows neurons to be voltage clamped with a single microelectrode, and the advantages of this circuit with respect to conventional bridge techniques are discussed. In this circuit, the single microelectrode is rapidly switched from a current passing to a recording mode. The circuitry consists of: (1) an electronic switch; (2) a high impedance, ultralow input capacity amplifier; (3) a sample-and-hold module; (4) conventional voltage clamping circuitry. The closed electronic switch allows current to flow through the electrode. The switch then opens, and the electrode is in a recording mode. The low input capacity of the preamplifier allows the artifact from the current pulse to rapidly abate, after which time the circuit samples the membrane potential. This cycle is repeated at rates up to 10 kHz. The voltage clamping amplifier senses the output of the sample-and-hold module and adjusts the current pulse amplitude to maintain the desired membrane potential. The system was evaluated in Aplysia neurons by inserting two microelectrodes into a cell. One electrode was used to clamp the cell and the other to independently monitor membrane potential at a remote location in the soma.

238 citations


Patent
27 May 1975
TL;DR: In this paper, an electrostatic device includes a fixed electrode to which is attached an end edge of a coiled or curved variable resilient sheet electrode, which is caused to unroll upon the application of an electric potential between the two electrodes.
Abstract: An electrostatic device includes a fixed electrode to which is attached an end edge of a coiled or curved variable resilient sheet electrode. An insulative layer separates the two electrodes, being either bonded to the fixed electrode or being bonded to the resilient electrode. The resilient variable electrode is caused to unroll upon the application of an electric potential between the two electrodes. The device is particularly adaptable for use as a light gate. It is capable of being actuated by an electrical potential either in a light transmission mode or in a variable reflectivity mode.

79 citations



Journal ArticleDOI
TL;DR: In this paper, the capacitance to ground and capacitance between objects of various shapes is calculated for a large number of electrode configurations and the results are presented graphically in a normalized form, and should permit a rapid and precise determination of capacitances for most practical electrode arrangements.
Abstract: Calculation of the capacitance to ground, as well as of the capacitance between objects of various shapes is a problem occurring frequently in high voltage engineering. Simple methods do not exist, however, for such calculations even in the case of some basic electrode configurations. Although general purpose computer programs may have been developed for most of the configurations, their availability is rather limited, and the data preparation often cumbersome. Accurate computer calculations of the capacitance to ground have been made for a large number of electrode configurations. The results are presented graphically in a normalized form, and should permit a rapid and precise determination of capacitances for most practical electrode arrangements. Furthermore, some simple equations have been developed which permit an approximate, but often sufficiently accurate, evaluation of the capacitances by hand calculations. It is believed that both the accurate graphs and the simple equations would be of great practical value, especially to high voltage engineers.

47 citations


Patent
21 Jul 1975
TL;DR: In this paper, a measuring cell for measuring electrical conductivity of liquids having a bore which in operation is contacted by a liquid, the conductivities of which is to be measured and a plurality of electrodes spaced along the bore and forming part of the bore surface, the electrodes being of coaxial annular form and including a first and a fourth electrode which constitute current electrodes for connection to a controllable AC current supply, a second and third electrode between the current electrodes and constituting voltage electrodes for connected to a high input impedance amplifier provided with means for employing the amplifier output to control
Abstract: A measuring cell for measuring electrical conductivity of liquids having a bore which in operation is contacted by a liquid, the conductivity of which is to be measured and a plurality of electrodes spaced along the bore and forming part of the bore surface, the electrodes being of coaxial annular form and including a first and a fourth electrode which constitute current electrodes for connection to a controllable AC current supply, a second and third electrode between the current electrodes and constituting voltage electrodes for connection to a high input impedance amplifier provided with means for employing the amplifier output to control the AC current supply to maintain sensibly constant the voltage at the voltage electrodes and a fifth electrode of annular form coaxial with the first to fourth electrodes and for connection to the first electrode by way of a buffer amplifier presenting a high impedance to the first electrode and a low impedance to the fifth electrode and located on the side of the first electrode remote from the fourth and voltage electrodes.

39 citations


Patent
18 Mar 1975
TL;DR: In this article, the shape and material structures of electrodes and insulators co-operate with each other to enable axial and/or radial flow of an electrolyte which is pumped through the electrode roll.
Abstract: Electrode arrangement for electrochemical cells. A deformable sandwich structure (working electrode, insulator, secondary electrode, insulator) forms a primary electrode arrangement. A three-dimensional structure can be formed by rolling up the primary sandwich structure around and axis. The shapes and material structures of electrodes and insulators co-operate with each other to enable axial and/or radial flow of an electrolyte which is pumped through the electrode roll. With such electrode rolls a high ratio of electrode surface to cell volume can be attained. Furthermore, by mounting one or more of the electrode rolls on a hollow axle and pumping the electrolyte through orifices of the axle from its interior into the electrode rolls, the scale-up of current and voltage of a cell is considerably facilitated and advantageously achieved.

24 citations


Patent
14 Apr 1975
TL;DR: In this article, an arc control circuit supplies voltage to an electrode of a portable analyzer for striking an arc against a specimen to provide an aerosol of the specimen material for analysis, and means for quenching the arc by opening the bypass switch to lower the electrode voltage once the arc has been maintained for a desired amount of time.
Abstract: An arc control circuit supplies voltage to an electrode of a portable analyzer for striking an arc against a specimen to provide an aerosol of the specimen material for analysis. The circuit includes a source of voltage and voltage dividing means for selectively applying different proportions of the source voltage to the electrode. Sensing means are coupled to the electrode for actuating bypass switching means coupled to the voltage dividing means when the electrode has made contact with the specimen to apply the full voltage of the power supply to the electrode to start the arc. As the electrode tip is withdrawn from the sample a predetermined distance, the desired arc is maintained. Means are provided for quenching the arc by opening the bypass switch to lower the electrode voltage once the arc has been maintained for a desired amount of time.

23 citations


Patent
12 Jun 1975
TL;DR: A cardiac pacer system includes a first relatively large contact area electrode for sensing cardiac activity and a second electrode of substantially smaller contact area than the first to apply artificial stimulating pulses to the heart.
Abstract: A cardiac pacer system includes a first relatively large contact area electrode for sensing cardiac activity and a second electrode of substantially smaller contact area than the first to apply artificial stimulating pulses to the heart. The first electrode has a sufficiently large contact area to achieve a relatively high sensitivity to cardiac activity and the second electrode has a sufficiently small contact area to generate a relatively high current density at the electrode-tissue interface when the artificial stimulating pulses are applied to the heart. The electrodes are supported in a spaced relationship by an electrically insulating spacer. Each electrode may be directly wired to an appropriate point within the cardiac pacer, and referenced to a common electrical return point by means of a third, common electrode. Alternatively, the first and second electrodes may be connected to the pacer with a single lead, with suitable decoupling circuitry between the single lead and each electrode. The third or common electrode may be eliminated by having the first and second electrodes each serve as a common electrode for the other, while employing suitable decoupling circuitry between the pacer and the electrodes.

20 citations


Patent
12 Sep 1975
TL;DR: In this article, a pair of high voltage switching circuits associated with first and second sources of voltage supply are connected with a pin-shaped record electrode through a resistor and an electrostatic induction plate, respectively.
Abstract: A pair of high voltage switching circuits associated with first and second sources of voltage supply are connected with a pin-shaped record electrode through a resistor and an electrostatic induction plate, respectively. The electrostatic induction plate is disposed very closely adjacent the record electrode or its associated lead wires in a manner to establish an electrostatic capacitive coupling therebetween. A resistor, capacitor combination provides an integration circuit for current flow from the first source of voltage supply to the record electrode and also provides a differentiation circuit for current flow from the second voltage supply source to the record electrode. Voltages from the first and second sources are added together in an incremental fashion via the resistor-capacitor combination. The sum of the voltages which exceeds the threshold value of the voltage, i.e. the ignition voltage, is applied to the record electrode to produce a spontaneous gas discharge.

18 citations


Patent
10 Apr 1975
TL;DR: A nonvolatile read mostly memory cell in a monocrystalline semiconductor body wherein the sensing of the information is achieved by measuring the substrate current is described in this article. But the authors do not consider the use of a gate dielectric layer to trap a charge.
Abstract: A non-volatile read mostly memory cell in a monocrystalline semiconductor body wherein the sensing of the information is achieved by measuring the substrate current. The cell includes spaced source and drain regions, a gate dielectric layer capable of trapping a charge, a substrate contact electrode; a means to induce a trapped charge into the gate dielectric layer, including a means to apply a voltage larger than the threshold voltage to the gate electrode to form an inversion layer, and a means to apply a voltage to the drain electrode causing channel current to flow; a means to remove the trapped charge, including a means to apply a voltage equal to or exceeding the avalanche voltage to the drain to cause avalanching; a means to determine the presence or absence of a charge in the gate dielectric including a means to apply a voltage to the gate which is larger than the threshold voltage and a voltage to the drain that is significantly less than the avalanche voltage, and a means to determine the substrate current.

16 citations


Patent
15 Aug 1975
TL;DR: In this article, a three-terminal resistor measuring system is presented for automatic control and detection in a threeterminal resistance measuring instrument, which is useful for the rapid measurement of the resistivity of various bulk material.
Abstract: A device is provided for automatic control and detection in a three-terminal resistance measuring instrument. The invention is useful for the rapid measurement of the resistivity of various bulk material with a three-terminal electrode system. The device maintains the current through the sample at a fixed level while measuring the voltage across the sample to detect the sample resistance. The three-electrode system contacts the bulk material and the current through the sample is held constant by means of a control circuit connected to a first of the three electrodes and works in conjunction with a feedback controlled amplifier to null the voltage between the first electrode and a second electrode connected to the controlled amplifier output. An A.C. oscillator provides a source of sinusoidal reference voltage of the frequency at which the measurement is to be executed. Synchronous reference pulses for synchronous detectors in the control circuit and an output detector circuit are provided by a synchronous pulse generator. The output of the controlled amplifier circuit is sampled by an output detector circuit to develop at an output terminal thereof a D.C. voltage which is proportional to the sample resistance R. The sample resistance is that segment of the sample between the area of the first electrode and the third electrode, which is connected to ground potential.

Journal ArticleDOI
TL;DR: In this article, the shape of the resistive electrode in the MHD generator was optimized by eliminating from the rectangular resistive electrodes the portion that produces the power loss, which has an effective internal resistance that is independent of the value of resistivity.
Abstract: Two-dimensional current distribution in two regions—resistive electrode and plasma—are studied to optimize the shape of the resistive electrode in the MHD generator Numerical computations are made for an example of potassium-seeded argon in non-equilibrium As a first step, the performance is analyzed on an electrode of rectangular shape, and calculations performed more quantitatively than in the previous work by Maxwell et al reveal that better uniformity is obtained for the current distribution along the electrode surface by increasing the thickness and resistivity of the electrode The uniformity is found to improve also when the load current is increased To diminish the power loss produced in the resistive layer, the electrode shape is optimized by eliminating from the rectangular resistive electrode the portion that produces the power loss The electrode thus optimized in shape has an effective internal resistance that is independent of the value of the resistivity of the resistive layer Conseque

Patent
Eugene C. Varrasso1
10 Nov 1975
TL;DR: In this paper, a method of anticipating electrode failure by monitoring the current, voltage and resistance between electrode pairs in a Joule effect heating system is presented, where a relatively rapid change in monitored resistance is an indication of an incipient failure.
Abstract: A method of anticipating electrode failure by monitoring the current, voltage and resistance between electrode pairs in a Joule effect heating system. A relatively rapid change in monitored resistance is an indication of an incipient failure. Alarm indicators, instruction print out, and/or process controls can be actuated in response to a given current voltage or resistance change. Plural electrode pairs are monitored by multiplexing to provide a repetitive cyclic scan of the parameters between pairs. Distortion of current and voltage values is minimized, where selective portions of regular power pulses are gated for control of heating, and complex waveforms result by employing true r.m.s. values of current and voltage developed in true r.m.s. to d.c. converters.

Patent
31 Jul 1975
TL;DR: In this article, a high frequency tubular ozonizer is described, in which low voltage and high voltage electrodes are coaxially disposed metal pipes, and a portion of the electrode disposed in a discharge gap, is coated with a dielectric.
Abstract: A high frequency tubular ozonizer in which low voltage and high voltage electrodes are coaxially disposed metal pipes. The high voltage electrode is made detachable, and a portion of the electrode disposed in a discharge gap, is coated with a dielectric. The low voltage electrode is cooled directly with a coolant flow. The ozonizer has a reliable centering device, due to which the low voltage and high voltage electrodes can be easily arranged coaxially. Low and high voltage units, in the ozonizer, can be easily assembled or taken apart. To increase the operating capacity ozonizers can be either coupled by means of common pipelines to form multielement installations or they can be coupled in a common housing.

Patent
29 Oct 1975
TL;DR: In this article, a cell for the measurement of electrical conductivity of liquids by the principle of the four electrode measuring technique in which two current electrodes are spaced from one another and voltage electrodes provide a voltage tap-off is described.
Abstract: A cell for the measurement of electrical conductivity of liquids by the principle of the four electrode measuring technique in which two current electrodes are spaced from one another and voltage electrodes provide a voltage tap-off. The voltage electrodes include at least two voltage electrodes associated with each current electrode and electrically connected in parallel. The at least two voltage electrodes are disposed along an equipotential line around a current electrode at positions on the equipotential line which exhibit low current density.

Patent
30 May 1975
TL;DR: In this paper, a particle charging device is described in which discharge electrodes and opposite electrodes are disposed in an opposed relationship, third electrodes being provided in the proximity of each discharge electrode, and there are provided a high voltage source for applying a periodically varying high voltage between said discharge and said third electrodes, a D.C. bias voltage between the above described electrodes.
Abstract: A particle charging device is herein disclosed in which discharge electrodes and opposite electrodes are disposed in an opposed relationship, third electrodes being provided in the proximity of each said discharge electrode, and there are provided a high voltage source for applying a periodically varying high voltage between said discharge electrodes and said third electrodes, a D.C. voltage source for applying a D.C. bias voltage between the above described electrodes, and a D.C. high voltage source for applying a D.C. high voltage between said third electrodes and said opposite electrodes, whereby during the periods when the periodically varying high voltage is not applied between said discharge electrodes and said third electrodes, D.C. corona discharge originating from said discharge electrodes may be always suppressed. Also an electric dust collecting apparatus making use of said particle charging device is disclosed herein.

Patent
21 Aug 1975
TL;DR: In this article, the electrode length in an electric furnace is measured by arranging a wire conductor to depend right above a hollow electrode such that it can be lowered and raised through the hollow electrode.
Abstract: The electrode length in an electric furnace is measured by arranging a wire conductor to depend right above a hollow electrode such that it can be lowered and raised through the hollow electrode. When the wire conductor is lowered through the hollow electrode and brought into contact with the molten process material within the electric furnace, an electric circuit constituted by the wire conductor, the process material and a power supply is closed so as to determine the electrode length extending below an electrode holder from a certain relation between the distance of descent of the wire conductor as indicated by a measuring means in accordance with current caused in the electric circuit upon closure thereof and a previously measured distance between the initial position of the end of the wire conductor before the descent thereof and the position of the electric holder.

Journal ArticleDOI
Richard P. Tison1
TL;DR: In this paper, a simple method was described and shown capable of measuring electric field strength in electrolytes using closely spaced inert electrodes, by monitoring the change in potential between bright platinum electrodes resulting from either a current interruption, or from a current pulse, superimposed on a direct current signal.

Patent
07 Jan 1975
TL;DR: In this paper, a drying device for drying wet coatings applied to substrates of low electrical conductivity comprising a series of parallel spaced-apart first electrodes of rod-like form between which is located a row of upstanding electrode spikes defining a second electrode.
Abstract: The invention relates to a drying device for drying wet coatings applied to substrates of low electrical conductivity comprising a series of parallel spaced-apart first electrodes of rod-like form between which is located a row of upstanding electrode spikes defining a second electrode. HT voltage is applied between the first and second electrodes and dries the coating on the substrate as it passes close to the electrode array.

Proceedings ArticleDOI
01 Jan 1975
TL;DR: In this paper, a charge coupled F.E.T. array is described which gives an amplified, non-destructive measure of the size of the charge packet under each electrode of a CCD line.
Abstract: A charge coupled F.E.T. array is described which gives an amplified, non-destructive measure of the size of the charge packet under each electrode of a CCD line. The basic concept uses the fact that the surface potential and consequently the depth of the depletion layer under any electrode of a CCD line is sensitive to the size of the Charge packet under that electrode. As a result, an integral array of F.E.T's can be formed simply by changing the electrode structure of one of the phases. Results from a four bit surface channel device in an n-type layer on a p-type substrate are used to illustrate the basic properties of the device.

Patent
David W. Meltzer1, John W. Trainor1
27 May 1975
TL;DR: In this article, the authors proposed a method for converting an optical image into an electrostatic image by focusing electrons passing through successive selected regions of the electrode on the conductor array, which can be scanned by the electrons passing there through.
Abstract: Apparatus and method for continuously converting an optical image into an electrostatic image. A vacuum tube device has a source of electrons and associated elements for propagating electronic charge toward an array of conductors coupling an interior surface of the vacuum tube device with an exterior surface of the device. The array of conductors has an extent substantially greater in a first dimension as compared to a second dimension. A photosensitive electrode, interposed between the electron source and the array of conductors modulates the passage of electrons from the source to the array. The modulation results from the presence of stored electronic charge on the electrode, the stored charge of local portion of electrode controlling the passage of electrons through apertures associated with the local portion of the electrode. The charge distribution on the photosensitive electrode can be determined by an optical image, applied to the electrode under appropriate conditions. Electron optics, associated with the vacuum tube device, focus electrons passing through the modulating electrode onto the conductor array. By focusing electrons passing through successive selected regions of the electrode on the conductor array, the charge distribution of the electrode can be scanned by the electrons passing therethrough. The array electrostatic charge, resulting from the deposition of electrons on the conductor array, can be continuously transferred to a dielectric material passing by the external surface of the conductor array. By synchronizing the passage of the dielectric material with the selected regions of the electrode, the stored electrical charge and therefore the optical image can determine an electrostatic image transferred to the dielectric material. The electrostatic image in the dielectric material can be processed and fixed by electrostatograhic techniques. Methods for locally altering the charge distribution are described.

25 Sep 1975
TL;DR: In this article, a technique of periodically anodizing oxygen sensing electrodes has been developed that appears to significantly delay or eliminate the slow downward drift in current, which is referred to as electrode "aging".
Abstract: : Work has been in progress towards developing oxygen sensing electrodes with long-term stability characteristics There are two types of changes that can occur with oxygen electrode responses One is noted by a comparatively rapid decrease in current output while the other is termed a slow drift of decreasing value in electrode current The latter phenomenon has been called electrode 'aging' and it is toward the solution of this problem that a great deal of effort has been directed A technique of periodically anodizing 02 sensing electrodes has been developed that appears to significantly delay or eliminate the slow downward drift in current Stable electrode currents for periods of three days have been obtained This periodic anodization seems to be effective only on electrodes whose surfaces have been activated by an anodization protocol The process appears to work on bare tipped as well as membrane coated electrodes (Author)

Journal ArticleDOI
TL;DR: These single‐unit studies reveal that it is possible to excite a series of restricted sectors of the acoustic nerve array from within the scala tympani, with appropriately positioned electrodes mounted in silastic carriers that fill theScala (displace perilymph).
Abstract: Neurophysiological and anatomical studies in cats have been directed toward determining the feasibility of development of a multichannel acoustic nerve stimulation prosthesis with potential application as an aid for profoundly deaf individuals with surviving acoustic nerve. From recording experiments taking advantage of the binaural frequency response characteristics of neurons within the central nucleus of the inferior colliculus, the pattern of excitation across the acoustic nerve array can be defined for any intracochlear electrode array. These single‐unit studies reveal that it is possible to excite a series of restricted sectors of the acoustic nerve array from within the scala tympani, with appropriately positioned electrodes mounted in silastic carriers that fill the scala (displace perilymph). Precisely constructed electrode arrays in carriers molded to fill the scala can be fabricated using dies of the scala made from soft‐metal cochlear casts. Implantation of these multichannel electrode arrays ...

Patent
05 Aug 1975
TL;DR: In this paper, a multistable device consisting of an emitter, an accelerating electrode and a collector, serving as the controlling element in conjunction with a control circuit, is used e.g. for the remote control of television receivers.
Abstract: A multistable device consisting of an emitter, an accelerating electrode and a collector, serving as the controlling element in conjunction with a control circuit, is used e.g. for the remote control of television receivers. The charge carriers as accelerated in the device, serve to supply atoms with excitation energy in the quantum-mechanical way by passing through various minimum and maximum speed values. From this, dynamic characteristics are obtained with multi-stable operating points. A closed control circuit is formed between the collector and the accelerating electrode, for causing stabilization at one of the possible voltage or current steps. Momentary variation of the accelerating voltage will effect the changing to different voltage or current steps.

Journal ArticleDOI
TL;DR: In this paper, a Stark modulator was used to avoid voltage fluctuations due to accumulation of electric charges in microwave spectroscopy of free radicals, where high voltage was alternately applied to each electrode so that the direction of the modulation electric field changes at every period.
Abstract: When using PTFE coated electrodes in microwave spectroscopy of free radicals, voltage fluctuations due to accumulation of electric charges appear. A special Stark modulator has been used to avoid these spurious features. With this device the high voltage is alternately applied to each electrode so that the direction of the modulation electric field changes at every period.