Abstract: Provided is a method and an apparatus for evaluating welding arc stability, a device and a medium, and belongs to the technical field of welding. The method includes: determining a plurality of indexes for evaluating arc stability, reference index values of each index and a number of evaluation levels according to sample acoustic emission signals; determining reference membership degrees of different indexes to different evaluation levels according to the reference index values of each index; determining an index value to be measured of each index according to the acquired acoustic emission signals to be measured; determining the membership degree to be measured of each index according to the index value to be measured of each index; and evaluating a level of the arc stability according to the membership degrees to be measured and the reference membership degrees.

Abstract: An apparatus for electrochemical detection of DNA hybridization utilizing oligonucleotide-containing polymer-coated electrodes, and an apparatus for electrochemical detection of nucleic acids in flowing streams using doped polymer-coated electrodes. Also provided are methods for detection of DNA hybridization and for detection of nucleic acids in flowing streams.