a darkfield light scattering platform for realtime monitoring of the erosion of microparticles by co2 monitoring chemical reactions using tools of analytical chemistry is crucial for understanding the mechanisms of these reactions in this study leaflike polypphenylenediamine pppd microparticles were prepared with precisely tailored properties the dark field microscopy protocol proved to be a powerful tool for studying the erosion of microparticles induced by co2 such a protocol can have the benefit of improving the understanding of reaction mechanisms and can help expand the applications of dark field microscopy a possible mechanism was proposed to explain the experimental observations inservice light path pmd polarization mode dispersion monitoring by pmd compensation we describe a novel method of measuring pmd polarization mode dispersion of an inservice dwdm system by pmd compensation we successfully demonstrate the method in a 1500km ultralong haul dwdm test bed we further verify the feasibility of the method for inservice light path pmd monitoring in a field trial in a revenuegenerating route in verizon network and obtain an accurate pmd value without impacting live network traffic the discrepancy between the measured and expected pmd values is less than 6 for all cases tested