No abstract

No abstract

An analysis of coherent optical FMCW is presented. It shows the limitations imposed on measurements of discrete reflections and of Rayleigh backscattering due to phase noise originating in the finite coherence length of the optical source. The dependence of the range for accurate measurements on particular parameters of the optical system is discussed in the general case and for three specific laser sources.

We have engineered the use of 2D, 1D and 0D carbon allotropes as spacers to achieve in excess of 1000-fold fluorescence enhancements in a Surface plasmon-coupled emission (SPCE) platform. We also have demonstrated the femtomolar sensitivity of silver decorated carbon dots (AgCD) in the detection of a radiating dipole.

Current‐potential relationships are derived for porous electrode systems following a homogeneous model and when adsorbed intermediates participate in the electrode reaction. Limiting Tafel slopes were deduced and compared with the corresponding behavior on planar electrode systems. The theoretical results showed doubling of Tafel slopes when the slow‐step is a charge‐transfer reaction and a nonlogarithmic current‐voltage behavior when the slow‐step is a chemical reaction. Comparison of the experimental results with theory for the case of oxygen reduction on carbon surfaces in alkaline media indicates that a slow chemical reaction following the initial charge‐transfer reaction to be the likely rate‐controlling step. Theoretical relationships are utilized to determine the exchange current density and the surface coverage by the adsorbed intermediates during the course of oxygen reduction from alkaline solutions on “carbon.” Tafel slope measurements on planar and porous electrodes for the same reaction are suggested as one of the diagnostic criteria for elucidating the mechanistic pathways of electrochemical reactions.