The electrochemical conversion of dichloroacetic acid to chloracetic\ud acid is investigated in conventional cells and in microreactors.\ud Two different microreactors are used: the first is\ud a filter press cell equipped with PTFE micrometric spacers, easy\ud to assemble and disassemble and available for a large variety\ud of electrodes and solvents; the second is made using an adhesive\ud spacer, micromilling and press and could easily be developed\ud on an industrial scale. The electrochemical synthesis is\ud performed successfully in the microreactors equipped with\ud a graphite cathode under proper operative conditions. The\ud performance of the process strongly depends on the nature of\ud the cathode and, for microreactors, on flow rate and current\ud density. Both microreactors give high conversions and selectivity\ud under a single-pass mode and are allowed to work without\ud supporting electrolyte at low cell voltages

No abstract

We report on the electrical and optical characterization,\ud in continuous wave regime, of a novel class of silicon\ud photomultipliers fabricated in standard planar technology on a\ud silicon p-type substrate. Responsivity measurements, performed\ud with an incident optical power down to tenths of picowatts, at\ud different reverse bias voltages and on a broad (340–820 nm)\ud spectrum, will be shown and discussed. The device temperature\ud was monitored, allowing us to give a physical interpretation of the\ud measurements. The obtained results demonstrate that such novel\ud silicon photomultipliers are suitable as sensitive power meters\ud for low photon fluxes

We report on Signal-to-Noise Ratio measurements carried out, in the continuous wave regime, at different bias voltages, frequencies and temperatures, on a class of silicon photomultipliers fabricated in planar technology on silicon p-type substrate. \ud Signal-to-Noise Ratio has been measured as the ratio of the photogenerated current, filtered and averaged by a lock-in amplifier, and the Root Mean Square deviation of the same current. The measured noise takes into account the shot noise, resulting from the photocurrent and the dark current. We have also performed a comparison between our SiPMs and a photomultiplier tube in terms of Signal-to-Noise Ratio, as a function of the temperature of the SiPM package and at different bias voltages. Our results show the outstanding performance of this class of SiPMs even without the need of any cooling system

No abstract