Self Assembling and Coordination of Water Nano-Layers On Polymer Coated Long Period Gratings: Toward New Perspectives for Cation Detection

In this work, polymeric coated Long Period Gratings (LPGs) working in transition mode have been used to monitor the coordination and self assembling of water nano-layers (typical thicknesses range in few tens of nanometers) providing new scenarios in chemical sensing applications. In particular, nano-scale layers (∼320nm) of semicrystalline syndiotactic and amorphous atactic polystyrene (sPS and aPS), have been deposited by dip-coating onto LPGs to tune the devices at the transition point. Experimental results demonstrate the polymers capability to orient water molecules in proximity of their surfaces. The sPS and aPS interactions with water have been continuously monitored and then compared demonstrating the higher capability of the crystalline phase of sPS to orient water nano-layers. Moreover, the high sensitivity of the coated LPGs was used to monitor the effect of disorder induced on the interfacial water molecular arrangement by different cations (sodium, Na+, potassium, K+, and calcium, Ca2+, ions) depending on their size and electrical charge. Experimental results show for the first time that, thanks to the water-polymer interaction, sPS coated LPGs could be successfully employed as high sensitivity cation sensors. In fact, the monitoring of the disorder induced by cations on the coordinated water layer leads to high sensitivities, in terms of detected RI change for unitary variation of concentration (∼7.80 · 10−4RIU · mM−1 for Na+ ions, ∼9.00 · 10−4RIU · mM−1 for K+ ions, and ∼1.07 · 10−3RIU · mM−1 for Ca2+ ions)

Demonstration in Space of a Smart Hyperspectral Imager for Nanosatellites

HyperScout is the first smart hyperspectral imager for nanosatellites. It has been launched on the 2nd of February 2018 at 8:51 CET, from the Jiuquan Satellite Launch Center in China. The launch vehicle Long March 2D lifted off on schedule and the satellite was separated from the launch vehicle minutes later. Approximately after 6 hours the first contact was established by GomSpace in Aalborg, Denmark. HyperScout is based on a long line of development led by cosine. The project to develop, build and launch the first HyperScout was funded by ESA, with support from the Dutch, Belgian and Norwegian national space organizations: Netherlands Space Office, BELSPO and Norsk Romsenter. cosine, as the prime contractor, enlisted the help of consortium partners S&T, TU Delft, VDL and VITO. The applications for which HyperScout has been conceived for are crop water management, fire hazard monitoring, flood detection, change detection of land use and land coverage and vegetation monitoring. The aim of the demonstration mission is to assess the quality of the data that will be acquired and the consequent suitability for the intended applications. Furthermore, the basic functionalities of the instrument as well as the onboard processing in real time will be demonstrated. The demonstration is divided in three operational blocks, during which HyperScout will be operated to acquire data from invariant sites for vicarious calibration, from application sites to qualify HyperScout for all the applications it has been conceived for, and to perform software experiments to demonstrate the novel approach to overcome the bandwidth limitation on small platforms. This paper reports about the outcome of the operations performed so far in orbit, and about the preliminary results obtained from the data evaluation performed during the demonstration project