5 results about "Impedance spectrum" patented technology

The invention provides a preparation method and application method of a sensorfor detecting a magnetic field based on magnetic induction protein.A micro-fluidic chip of a three-electrode system is prepared and grapheme working electrodes are modified with the magnetic induction protein by a covalent self-assembly mode. When the magnetic field is added externally, the magnetic induction protein produces response, protein conformation and dielectric properties change and impedance changes, and magnetic signals are converted into electrical signals. Detection of the magnetic field is achieved through an electrochemical detection impedance spectrum. According to the preparation method and application method of the sensor for detecting a magnetic filed based on magnetic induction protein, anovelmagnetic field detection device is designed and a novel detection method for the magnetic field is achieved through bionic design.

The present invention relates to a method for evaluating the crosslink degree of a vulcanized sample in real time during a vulcanization process or diagnosing the electrical properties of the sample after the completion of the vulcanization process, and then determining an optimal vulcanization time and an optimal content of each constituent gradient of a composition for vulcanization that optimize the properties of the composition according to the vulcanization conditions, for the sake of improving the properties of the vulcanized sample prepared from a polymer by vulcanization at a high temperature.The method for determining an optimal vulcanization time and an optimal content of each constituent gradient of a composition for vulcanization that optimize the properties of the composition according to the vulcanization conditions includes: (a) measuring an impedance spectrum in a specific frequency range in the individual vulcanization condition; (b) approximating the measured impedance spectrum to an equivalent circuit model consisting of resistance and capacitance components; (c) determining a polymer resistance Rp (i.e., a value obtained by subtracting a real part of the impedance measurement at a maximum frequency from a real part of the impedance measurement at a minimum frequency, or the magnitude of a real part of the semicircle in a Nyquist diagram) from the determined parameters; (d) determining, as an optimal end point of vulcanization, a time point at which the increasing rate of the polymer resistance Rp rapidly slows down; and (e) determining the optimal content of each constituent ingredient of the composition for vulcanization when the polymer resistance Rp of the sample completely vulcanized is at its minimum.