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A silver nanowire (AgNW) based conductor is a promising component for flexible and stretchable electronics. A wide range of flexible/stretchable devices using AgNW conductors has been demonstrated recently. High-resolution, high-throughput printing of AgNWs remains a critical challenge. Electrohydrodynamic (EHD) printing has been developed as a promising technique to print different materials on a variety of substrates with high resolution. Here, AgNW ink was developed for EHD printing. The printed features can be controlled by several parameters including AgNW concentration, ink viscosity, printing speed, stand-off distance, etc . With this method, AgNW patterns can be printed on a range of substrates, e.g. paper, polyethylene terephthalate (PET), glass, polydimethylsiloxane (PDMS), etc. First, AgNW samples on PDMS were characterized under bending and stretching. Then AgNW heaters and electrocardiogram (ECG) electrodes were fabricated to demonstrate the potential of this printing technique for AgNW-based flexible and stretchable devices. 

Subcritical hydrothermal liquefaction uses high temperatures (270-350°C) and high pressures (80-173 bar) to produce bio-crude oils that can be upgraded to liquid transportation fuels. In this study, two strains of Galdieria sulphuraria, an acidophilic, mixotrophic red microalgae, were cultivated on effluent from primary settling tanks at a municipal wastewater treatment plant. Samples were concentrated to 5 and 10 wt.% slurries after harvest and converted by hydrothermal liquefaction in a 1.8 L batch reactor. Reaction conditions included temperatures of 310, 330 and 350°C, and hold times of 5, 30 and 60 minutes. Yields and product properties were compared to those of hydrothermal liquefaction of Galdieria sulphuraria grown on media. Total oil yields were low (11-18 wt.%) and char yields were high (28-36 wt.%) compared to those from HTL of the algae grown on media (27-35 wt.% oil and 10-13 wt.% char), likely due to the higher ash content and lower lipid content of the algae grown on wastewater. The bio-crude oil, char, and aqueous phase samples were characterized to complete mass, energy and nutrient balances to characterize the tradeoffs in the algae growth and conversion systems for energy and nutrient recovery.