42results about How to "Reduce AC impedance" patented technology

A light-emitting device and an illumination apparatus are disclosed. A plurality of LED elements (91) are connected in series between positive and negative lines (9a and 9b), and first bypass capacitor (92) is connected in parallel to the LED elements respectively. Each series circuit of a predetermined number of LED elements is connected in parallel to second bypass capacitors (93a, 93b and 93c). As a result, with the negative power line (9b) set as a grounding point (A), the AC impedance at connection points (B, C, D) of the series circuit of the LED elements (91a to 911) against the ground is reduced. Thus, the erroneous lighting or ''flicker'' of each LED which otherwise might be caused by an external noise is prevented.

The invention discloses a polyaniline hollow microsphere / zinc composite positive electrode material and a button-type lithium battery. The active material of the positive electrode material is polyaniline hollow microsphere mixed with microspherical zinc powder; the button-type lithium battery includes a positive electrode , negative electrode, diaphragm, electrolyte and shell, the positive electrode is made of active material, acetylene black and polytetrafluoroethylene emulsion positive electrode material; the positive electrode material of button lithium battery has large specific surface area, high conductivity and good stability; further preparation The lithium battery has low AC impedance, good cycle performance, and has broader application potential.

The invention discloses a symmetrical button type supercapacitor electrode material and a symmetrical button type supercapacitor. The electrode material comprises a polyaniline hollow microballoon active substance whose surface is doped with trivalent cerium ions. The material has the advantages of large specific capacity, high energy density, high electrochemical activeness and the like, can be applied to preparation of an electrode slice material of a symmetrical button type supercapacitor, and can obtain a symmetrical button type supercapacitor advantaged in large specific capacity, small AC impedance and good voltage maintenance capability.

A high-temperature planar transformer using metal-bonded ceramic substrates, including a double-ring closed structure magnetic core spliced ​​by a group of iron-nickel-molybdenum metal magnetic powder cores; multiple groups of ceramic substrate planes using metal-bonded technology coils, and all planar coil assemblies make up the primary and secondary windings of the transformer. The ceramic substrate used in the high-temperature planar transformer has a mounting hole for placing a magnetic core made of metal magnetic powder core, and two parts of the magnetic core are respectively put into the mounting hole from both sides of the ceramic substrate, and bonded together as a whole. Compared with traditional wire-wound transformers and planar transformers, the present invention is a high-temperature planar transformer using metal-bonded ceramic substrates. Inductance and distributed capacitance, improve heat dissipation efficiency, and can work for a long time in a high temperature environment above 200 ℃, so that the heat dissipation design of the transformer can be simplified, the size and weight of the transformer can be reduced, and it also meets the high temperature requirements of aerospace, oil drilling, etc. Design requirements for switching power supplies in the environmental industry.

The invention provides a modified carbon nano tube and a preparation method thereof, a lithium ion battery anode and a preparation method thereof and a lithium ion battery. The modified carbon nano tube comprises a carbon nano tube and a polar group on the surface of the carbon nano tube, wherein the polar group is -COOLi. The modified carbon nano tube provided by the invention has the characteristics of being easy to disperse, low in dispersing cost and good in electrical conductivity; compared with a lithium ion battery adopting the dispersion liquid of an unmodified carbon nano tube as a conductive agent, the lithium ion battery adopting the dispersion liquid of the carbon nano tube as a conductive agent has a lower direct current impedance and alternating-current impedance, and is greatly improved in the high-rate charge-discharge capability.

The invention discloses a platinum black pulse plating method based on ultrasonic assistance and belongs to the field of biomedicine engineering technology. The method comprises the steps of: vertically putting an electrode to be platinized and a platinum wire auxiliary electrode into an electroplate liquid and respectively connecting with the positive pole and the negative pole of a power supply; then applying pulse current and starting an ultrasonic device at the same time; and finally turning off the power supply and the ultrasonic device, taking the platinized electrode out and washing with deionized water to obtain a platinum black plating layer attached to the platinized electrode. The platinum black obtained by the invention can obtain greatly reduced particle diameter and better bonding force between the plating layer and a microelectrode substrate and is not easy to fall off to cause failure of the electrode; in addition, the platinized microelectrode obtains greatly reduced AC impedance and greatly increased electrode charge injection capacity and charge storage capacity, which is beneficial to the reduction of embedded system power consumption and the improvement of electric stimulus effect.

The invention relates to the technical field of phosphorus molybdenum oxide supercapacitor materials, and discloses a polypyrrole-phosphorus molybdenum oxide supercapacitor material and a preparation method thereof, including the following formula raw materials: phosphomolybdenum acid, 1,3,6,8- Tetrakis(4-carboxyphenyl)pyrene, cobalt nitrate hexahydrate, pyrrole, initiator. The polypyrrole-phosphorus molybdenum oxide supercapacitor material and its preparation method, the cobalt-doped phosphorus molybdenum oxide has a stable regular octahedral pyramidal structure, which improves the electrochemical stability of the phosphorus molybdenum oxide, and the cobalt-doped phosphorus molybdenum oxide The oxide has good electrical conductivity and conductivity, which promotes the transmission and migration of charges between the electrolyte and the supercapacitor, and greatly increases the double-layer capacitance and pseudocapacitance of the supercapacitor. Polypyrrole has excellent conductivity. The conductive network formed on the surface of the molybdenum oxide provides active sites, which promotes the charge transport between the molybdenum phosphorus oxide and the electrolyte, and improves the capacitance and energy density of the supercapacitor.

The invention is a micron flower spherical high-performance full-splitting bifunctional electrocatalyst FeOOH / Ni 3 S 2 method of preparation. In this method, thiourea and nickel nitrate are used as raw materials, ethanol is used as a solution, and hexadecyltrimethylammonium bromide is used as a surfactant, and Ni is grown in situ on a foamed nickel substrate by a solvothermal method. 3 S 2 , and then by one-step electrochemical deposition on Ni 3 S 2 micron flower spherical FeOOH / Ni 3 S 2 electrocatalyst. The FeOOH / Ni that the present invention obtains 3 S 2 The composite catalyst has low overpotential and good stability, and has broad application prospects in the preparation of electrocatalytic water splitting to produce hydrogen clean energy.

The invention discloses a method for preparing a graphene / sodium manganate flexible thin film and a method using the graphene / sodium manganate flexible thin film to prepare an aqueous sodium-zinc compound battery, relates to methods for preparing graphene thin films and methods using the graphene thin films to prepare compound batteries, and aims to solve the problem that an existing battery anode material is complex in preparation process, low in conductivity and unstable in electrochemical performance. The method for preparing the graphene / sodium manganate flexible thin film includes the steps of firstly, preparing Na4Mn9O18 powder; secondly, adding graphene oxide into deionized water, and performing ultrasonic treatment to obtain a solution A; thirdly, preparing a graphene oxide / sodium manganate flexible thin film; fourthly, drying the graphene oxide / sodium manganate flexible thin film to obtain the graphene / sodium manganate flexible thin film. The prepared graphene / sodium manganate flexible thin film is simple in process, has sufficient toughness, can be curled at will and can be directly cut to serve as a flexible electrode. By the methods, the graphene / sodium manganate flexible thin film and the aqueous sodium-zinc compound battery can be prepared.

The invention provides a contact detecting circuit which surely detects the open / close of contact of a switch, etc., to provide a load drive device and also to provide a dental syringe with a built-in illuminator and can improve its durabil ity, operability, etc. A load drive device consists of a handpiece main body and a load control circuit. The main body contains an illumination power supply and a switch which includes the conduction members. The circuit contains an oscillation circuit which generates an AC signal to be applied to the member, a signal detecting circuit which rectifies and smoothes the signal received from the member when the switch is closed, a comparator which compares the output signal of the circuit with the prescribed reference value, a control circuit, and a drive circuit which supplies the power to the power supply from a power circuit based on the control signal of the circuit.

The invention discloses a Ce-doped polyaniline / active carbon hybrid button supercapacitor. The capacitor comprises a capacitor housing, an anode sheet, a cathode sheet, a diaphragm and an electrolyte, wherein the anode sheet is prepared by a polyaniline hollow microballoon active substance whose surface is doped with trivalent cerium ions, and the cathode sheet is prepared by a cathode material containing an active carbon active substance. The Ce-doped polyaniline / active carbon hybrid button supercapacitor obtained after assembling is large in specific capacity, small in AC impedance and quite small in leakage current density.

The invention provides a preparation method of an electroplated silver carbon fiber electrode. The preparation method comprises the following steps of weighing carbon fiber bundle and soaking the carbon fiber bundle in an acetone solution, then performing ultrasonic treatment, and soaking the carbon fiber bundle in an ethanol solution for ultrasonic treatment; placing the carbon fiber bundle in amuffle furnace for thermal oxidation treatment, then performing ultrasonic cleaning with deionized water, and then placing in a drying oven for drying; cutting the carbon fiber bundle subjected to oxidation treatment to a certain length, and binding one end of the cut carbon fiber bundle with a silver wire for fixation; mixing AgNO<3> and NaNO<3> solution to prepare electroplating solution, placing a pair of carbon fiber bundles in the electroplating solution, supplying voltage by a constant-voltage power supply, electroplating the carbon fiber bundles to obtain silver-plated carbon fibers, and packaging the silver-plated carbon fibers in a heat-shrinkable tube to obtain the silver-plated carbon fiber electrode. The preparation method is simple; and the electroplated silver carbon fiber electrode prepared by the method has small range, stable performance, and easy long-term storage and can be used for detecting ocean electric field signals.