Abstract: A method for creating nanoparticles directly from bulk metal by applying ultrasound to the surface in the presence of a two-part surfactant system. Implosive collapse of cavitation bubbles near the bulk metal surface generates powerful microjets, leading to material ejection. This liberated material is captured and stabilized by a surfactant bilayer in the form of nanoparticles. Nanoparticles can be produced regardless of the bulk metal form factor. The method is generally applicable of metals and alloys. The method can be applied to an environmentally important problem, the reclamation of gold from an electronic waste stream.

Abstract: Various technologies pertaining to formation or treatment of a thallium bromide crystal to improve the operable lifespan of a device that incorporates the thallium bromide crystal are described herein. In exemplary embodiments, treatments including focused ion beam implantation, selective material removal, and buffer layer application are performed on a thallium bromide crystal to inhibit motion of dislocations toward a region at which an electrical contact is desirably installed. In other exemplary embodiments, a thallium bromide crystal is doped with impurities during formation that inhibit the motion of dislocations in the crystal. In still other exemplary embodiments, a thallium bromide crystal is formed by way of processes that inhibit dislocation formation during crystal growth or eliminate dislocations in an existing thallium bromide mass.

Abstract: Ion-doped metal or ceramic nanoparticles can be added into, for example, a component that upon exposure to an environmental stimulus, will release the ion and ‘tattle’ on any impending destruction.

Abstract: Falling particle solar receivers, systems, and methods are disclosed that include one non-linear falling particle curtain or two or more falling particle curtains within a solar receiver that receives incident solar radiation. The particles heated in the solar receiver may be used to heat a secondary fluid. In an embodiment, the particles may be recirculated to improve energy capture and thermal efficiency. In other embodiments, an air curtain may be used across the aperture of the receiver, and flow-control devices may be used to evenly spread particles across the width of the receiver inlet. Finally, feed particles may be preheated using heat from the solar receiver.

Abstract: A mixed compound glass scintillator includes a first compound and a second compound. The first compound has a Tg greater than 25° C., is organic, is capable of generating luminescence in the presence of ionizing radiation. The first compound includes a central species and a luminescent organic group bonded to the central species or to an optional organic linker group. The central species is selected from the group consisting of: carbon, silicon, and tin. The optional organic linker group, if present, is bonded to the central species and the luminescent organic group. The second compound also has a Tg greater than 25° C. The first and second compound are mixed and melted to form a glass material.

Abstract: A magnetoelastically actuated device includes a microscale cantilever arm supported at a standoff distance from a substrate. The cantilever arm is formed as a laminar magnetic actuator configured to bend when it is subjected to a magnetic field. The cantilever arm includes a film of magnetostrictive material. Also provided is a method for fabricating the magnetoelastically actuated device. The method includes defining an actuator mold in a layer of photoresist on a structural layer of the cantilever arm and electrodepositing a layer of a magnetostrictive alloy containing cobalt and iron onto the structural layer within the actuator mold.

Abstract: A high current density, low contact resistance contact for wide bandgap (WBG) or ultra-wide bandgap materials (UWBG) is disclosed. The contact is lithographically formed so that a total perimeter length of the contact structure is at least twice the length of the side of a contact pad closest to the gate in a high electron mobility transistor (HEMT). The contact structure may take the form of a plurality of columns having various cross-sectional shapes, or may take the form of a convoluted geometrical shape, such as a comb-like, serpentine, or spiral shape. The depth of the contact structure permits direct contact with the two-dimensional electron gas (2DEG) in the HEMT by the perimeter of the contact structure. The contact structure is formed of at least one metal layer, at least one doped material regrown layer, or at least one implanted region. The contact structure may be applied to other WBG and UWBG devices.

Abstract: The invention provides a green chemistry, aqueous method to synthesize gold nanoparticles directly from bulk gold sources. The method involves the ultrasonication of bulk gold in water in the presence of an alkythiol species and a quaternary ammonium surfactant. An organic bilayer forms on the surface of the gold which renders it susceptible to material ejection from the violent collapse of cavitation bubbles. This ejected material is stabilized in solution by the formation of an organic bilayer and can be easily separated. It can then be subjected to an aqueous digestive ripening step to give a gold nanoparticle ensemble with a well-defined plasmon resonance. This method is applicable to a number of different sources of bulk gold. The method can be applied to an environmentally important problem; the recovery of gold from electronic waste streams. For example, gold nanoparticles can be extracted directly from the surface of SIM cards, with no prior manipulation of the cards necessary.

Abstract: Systems and methods that increase the residence time of particles falling through a solar receiver using an induced magnetic field to suspend or slow down and/or alter the flight path of the particles falling through the concentrated beam of sunlight are disclosed.

Abstract: A non-volatile memory device is described herein. The non-volatile memory device includes a diffusive memristor electrically coupled to a redox transistor. The redox transistor includes a gate, a source, and a drain, wherein the gate comprises a first storage element that acts as an ion reservoir, and a channel between the source and the drain comprises a second storage element, wherein a state of the memory device is represented by conductance of the second storage element.

Abstract: A process for metallizing a three-dimensional-printed polymeric structure includes soaking the three-dimensional-printed polymeric structure in a metal salt solution; transferring the three-dimensional polymeric structure to a solution comprising a first reducing agent; soaking the three-dimensional polymeric structure in a metal plating bath, the metal plating bath comprising a coordinating agent, a palladium or platinum salt, a pH buffer component, and a second reducing agent, to form a metal plated polymeric structure. A metal plated porous structure and an apparatus for improving metallization are also disclosed.

Abstract: A sodium ion battery comprises a cathode having a porous redox active metal-organic framework material. The battery can be an organic electrolyte sodium ion battery wherein the electrolyte comprises a sodium salt dissolved in an organic solvent or mixture of organic solvents. Alternatively, the battery can comprise an aqueous sodium ion battery wherein the electrolyte comprises a sodium salt dissolved in an aqueous solvent. Battery performance is especially related to electrolyte and binder selection.

Abstract: Additively manufactured monolithic structures for containing and directing flows of fluids are described herein, which can achieve high contact area between fluids and solids while maintaining uniform flow conditions and requiring low applied pressures to yield desired flow rates, for use in heat exchangers, chromatography columns, catalytic converters, etc. An exemplary monolithic structure comprises a plurality of tiled unit cells having a same shape, where the tiled unit cells are integrally formed as a single component. The tiled unit cells are arranged to define one or more interior regions of fluid flow, one or more inlets to each interior region of fluid flow, and one or more outlets to each interior region of fluid flow. The structures and methods of tiling herein are suited to additive manufacturing technologies such as projection stereolithography, multiphoton lithography, etc.

Abstract: Various technologies for mitigating interference artifacts in multi-pass synthetic aperture radar (SAR) imagery are described herein. First and second phase histories corresponding to first and second SAR passes over a scene are processed in image and phase-history domains to correct for spatially-variant and constant phase offsets between the phase histories that can be caused by known and unknown variations in motion of a SAR platform between passes. Data samples from one phase history can then be replaced with data samples from the other phase history to remove artifacts and distortions caused by sources of interference in the scene.

Abstract: Multi-resonant control of a 3 degree-of-freedom (heave-pitch-surge) wave energy converter enables energy capture that can be in the order of three times the energy capture of a heave-only wave energy converter. The invention uses a time domain feedback control strategy that is optimal based on the criteria of complex conjugate control. The multi-resonant control can also be used to shift the harvested energy from one of the coupled modes to another, enabling the elimination of one of the actuators otherwise required in a 3 degree-of-freedom wave energy converter. This feedback control strategy does not require wave prediction; it only requires the measurement of the buoy position and velocity.

Abstract: A method for programming substantially simultaneously more than one of the three-terminal memory cells that represent the values of a matrix to be multiplied by a vector is disclosed. Programming may be achieved by controlling the gate-drain voltage for more than one cell simultaneously to change each such cell's physical state and hence its effective resistance. Illustratively, the gates of each row of the cells corresponding to the matrix are coupled together and each coupled row is coupled to a respective controllable voltage source while the drains of each column of the cells of the matrix are coupled together and each coupled column is coupled to a respective controllable voltage source. The controllable voltage sources are arranged so that at the intersection of a row and a column, a cell experiences one of three conditions: increase effective resistance, decrease effective resistance, or substantially no change.

Abstract: An electro-acoustic device includes a plurality of suspended, piezoelectric, acoustically waveguiding membranes supported in a common plane. An input transducer coupled to one of the waveguiding membranes converts input electrical signals to traveling-wave acoustic signals. An output transducer coupled to one of the waveguiding membranes converts acoustic signals to electrical signals. At least two of the waveguiding membrane have parallel straight sections that are longer than a guided acoustic wavelength and that are mutually separated by an air gap having a width less than the guided acoustic wavelength.

Abstract: A stabilized scintillator includes a compound corresponding to formula (2) or (3), or activated derivatives thereof: A2BB?xB?yX6??(2) A2BB?XxX?y??(3) wherein A and B are monovalent cations, B? is a trivalent cation, X is a halogen, x and y are molar percentages, x+y=1; B? is an aliovalent exchange cation that has a different valence than B?, X? is an aliovalent exchange anion that has a different valence than X. A method of preparing the stabilized scintillator is also disclosed.

Abstract: There is provided a near-zero-power wakeup system in which a MEMS sensor for mechanical or acoustic signals is coupled to a very-low-power complementary metal oxide semiconductor (CMOS) application-specific integrated circuit (ASIC). Power consumption can be minimized by operating the ASIC with sub-threshold gate voltages.

Abstract: A mechanical testing apparatus for a specimen is presented. The mechanical testing apparatus comprises a drop table system and a Hopkinson bar. The drop table system has a drop carriage. The Hopkinson bar is positioned parallel to a motion of the drop carriage and connected to the drop table system by the specimen.