Charge conservation elementary charge on positive and negative particles must be extremely close to equal, differing by no more than a factor of 10 for the case of protons and electrons. Ordinary matter contains equal numbers of positive and negative particles, protons and electrons, in enormous quantities. If the elementary charge on the electron and proton were even slightly different, all matter would have a large electric charge and would be mutually repulsive. The best experimental tests of electric charge conservation are searches for particle decays that would be allowed if electric charge is not always conserved. No such decays have ever
Imaging particle analysis Imaging particle analysis Imaging particle analysis is a technique for making particle measurements using digital imaging, one of the techniques defined by the broader term particle size analysis. The measurements that can be made include particle size, particle shape (morphology or shape analysis and grayscale or color, as well as distributions (graphs) of statistical population measurements. Imaging particle analysis uses the techniques common to image analysis or image processing for the analysis of particles. Particles are defined here per particle size analysis as particulate solids, and thereby not including atomic or sub-atomic particles. Furthermore, this article is limited to real