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 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.