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QBD is the term applied to the charge-to-breakdown measurement of a semiconductor device. It is a standard destructive test method used to determine the quality of gate oxides in MOS devices. It is equal to the total charge passing through the dielectric layer (i.e. electron or hole fluence multiplied by the elementary charge) just before failure.
IEC 60172 Test procedure for the determination of the temperature index of enamelled and tape wrapped winding wires; IEC 60183 Guidance for the selection of high-voltage A.C. cable systems; IEC 60188 High-pressure mercury vapour lamps – Performance specifications; IEC 60189 Low-frequency cables and wires with PVC insulation and PVC sheath
Battery tester. A battery tester is an electronic device intended for testing the state of an electric battery, going from a simple device for testing the charge actually present in the cells and/or its voltage output, to a more comprehensive testing of the battery's condition, namely its capacity for accumulating charge and any possible flaws affecting the battery's performance and security.
The charge control consists of a pressure switch built into the cell, which disconnects the charging current when the internal cell pressure rises above a certain limit; usually 200 pounds per square inch (1.4 MPa) to 300 pounds per square inch (2.1 MPa). This prevents overcharging and damage to the cell.
Coulometry is the measure of charge, thus named after its unit the coulomb. Michael Faraday, known for his work in electricity and magnetism, made critical contributions to the field of electrochemistry. He discovered the laws of electrolysis, and in his recognition is the eponym of the Faraday constant.
Flow cytometry (FC) is a technique used to detect and measure the physical and chemical characteristics of a population of cells or particles. [1] [2] [3] [4]In this process, a sample containing cells or particles is suspended in a fluid and injected into the flow cytometer instrument.
In practice the conductivity cell is calibrated by using solutions of known specific resistance, ρ*, so the individual quantities l and A need not be known precisely, but only their ratio. [11] If the resistance of the calibration solution is R * , a cell-constant, defined as the ratio of l and A ( C = l ⁄ A ), is derived.
Previously, this procedure involved preparing a peripheral blood smear and manually counting each type of cell under a microscope, a process that typically required a half-hour. A Coulter counter played an important role in the development of the first cell sorter , and was involved in the early development of flow cytometry .