A Machine Learning and Computer Vision Approach to Rapidly Optimize Multiscale Droplet Generation.

Generating droplets from a continuous stream of fluid requires precise tuning of a device to find optimized control parameter conditions. It is analytically intractable to compute the necessary control parameter values of a droplet-generating device that produces optimized droplets. Furthermore, as the length scale of the fluid flow changes, the formation physics and optimized conditions that induce flow decomposition into droplets also change.

Tunable Molybdenum Disulfide-Enabled Fiber Mats for High-Efficiency Removal of Mercury from Water.

The application of molybdenum disulfide (MoS) for water decontamination is expanded toward a novel approach for mercury removal using nanofibrous mats coated with MoS. A bottom-up synthesis method for growing MoS on carbon nanofibers was employed to maximize the nanocomposite decontamination potential while minimizing the release of the nanomaterial to treated water. First, a co-polymer of polyacrylonitrile and polystyrene was electrospun as nanofibrous mats and pretreated to form pristine carbon fibers.

Electrospun silica nanofiber mats functionalized with ceria nanoparticles for water decontamination.

This study demonstrates the fabrication of nanoceria-immobilized silica nanofibers for efficient water decontamination with easy reuse and regeneration properties. Commercially-available ceria (CeO) nanoparticles were immobilized on electrospun silica nanofiber mats. Optimal conditions for both oxidation of model trace organic compounds (TrOCs) and hydroxyl-radical formation were determined in batch experiments with ceria nanoparticles.

Role of Ionic Charge Density in Donnan Exclusion of Monovalent Anions by Nanofiltration.

The main objective of this study is to examine how the charge densities of four monovalent anions-fluoride (F), chloride (Cl), bromide (Br), and nitrate (NO)-influence their Donnan (charge) exclusion by a charged nanofiltration (NF) membrane. We systematically studied the rejection behavior of ternary ion solutions containing sodium cation (Na) and two of the monovalent anions as a function of the pH with a polyamide NF membrane. In the solutions containing F and Cl or F and Br, F rejection was higher than Cl or Br rejection only when the solution pH was higher than 5.

Heterogeneous WSx/WO₃ Thorn-Bush Nanofiber Electrodes for Sodium-Ion Batteries.

Heterogeneous electrode materials with hierarchical architectures promise to enable considerable improvement in future energy storage devices. In this study, we report on a tailored synthetic strategy used to create heterogeneous tungsten sulfide/oxide core-shell nanofiber materials with vertically and randomly aligned thorn-bush features, and we evaluate them as potential anode materials for high-performance Na-ion batteries. The WSx (2 ≤ x ≤ 3, amorphous WS3 and crystalline WS2) nanofiber is successfully prepared by electrospinning and subsequent calcination in a reducing atmosphere.

Antimicrobial Electrospun Biopolymer Nanofiber Mats Functionalized with Graphene Oxide-Silver Nanocomposites.

Functionalization of electrospun mats with antimicrobial nanomaterials is an attractive strategy to develop polymer coating materials to prevent bacterial colonization on surfaces. In this study we demonstrated a feasible approach to produce antimicrobial electrospun mats through a postfabrication binding of graphene-based nanocomposites to the nanofibers' surface. A mixture of poly(lactide-co-glycolide) (PLGA) and chitosan was electrospun to yield cylindrical and narrow-diameter (356 nm) polymeric fibers.

Membrane-based osmotic heat engine with organic solvent for enhanced power generation from low-grade heat.

We present a hybrid osmotic heat engine (OHE) system that uses draw solutions with an organic solvent for enhanced thermal separation efficiency. The hybrid OHE system produces sustainable energy by combining pressure-retarded osmosis (PRO) as a power generation stage and membrane distillation (MD) utilizing low-grade heat as a separation stage. While previous OHE systems employed aqueous electrolyte draw solutions, using methanol as a solvent is advantageous because methanol is highly volatile and has a lower heat capacity and enthalpy of vaporization than water.