Three regimes of water adsorption in annealed silica opals and optical assessment.

Physisorbed and structurally bound (surface and internal) water in silica opals are distinguished and quantified by thermogravimetry. By controlled dehydroxylation with thermal annealing, we correlate these forms of water with the silica chemistry. In particular, we find that the silica capability to physically adsorb water from ambient moisture exhibits three regimes, associated with the distinct condensation behavior of bonded and unbonded surface silanols.

Transmittance photoplethysmography with near-infrared laser diodes in intra-peritoneal organs.

Photoplethysmography and pulse oximetry are techniques based on optical principles, which are widely used in medical practice for non-invasive monitoring. There are some processes which may affect specific organs or parts without a significant repercussion on the information provided non-invasively. Here, we report on the preliminary results obtained by transmittance photoplethysmography in pig intra-peritoneal organs along a surgical intervention, using a measurement system based on two near-infrared laser diodes.