Abstract: Apparatus and methods are disclosed for mixing and self-cleaning elements in microfluidic systems based on electrothermally induced fluid flow. The apparatus and methods provide for the control of fluid flow in and between components in a microfluidic system to cause the removal of unwanted liquids and particulates or mixing of liquids. The geometry and position of electrodes is adjusted to generate a temperature gradient in the liquid, thereby causing a non-uniform distribution of dielectric properties within the liquid. The dielectric non-uniformity produces a body force and flow in the solution, which is controlled by element and electrode geometries, electrode placement, and the frequency and waveform of the applied voltage.

Abstract: A method for preparing a gelled liquid propane (GLP) composition comprises the introduction of liquid propane into an evacuated mixing vessel containing a gellant and mixing the liquid propane with the gellant. A bi-propellant system comprising GLP is particularly well-suited for outer planet missions greater than 3 AU from the sun and also functions in earth and near earth environments. Additives such as powders of boron, carbon, lithium, and/or aluminum can be added improve performance or enhance hypergolicity. The gelling agent can be silicon dioxide, clay, carbon, or organic or inorganic polymers. The bi-propellant system may be, but need not be, hypergolic.

Abstract: Disclosed is an electrostatic aerosol concentrator for the concentration of aerosol particles and their collection for subsequent analysis. The concentrator comprises an airflow chamber that includes alternately energized and grounded electrode elements that work in concert to impart radial inward motion to charged aerosol particles and focusing them toward an enriched aerosol outlet. If desired, filtered air inlets may be used to provide a sheath of aerosol-free air along the chamber periphery and prevent deposition of particles onto electrode surfaces. Aerosol particles entering the airflow chamber may carry a positive or negative charge naturally, or a charge may be induced on the particles using a charging section located upstream of the aerosol inlet. Natural or induced charges on the aerosol particles may be used to selectively concentrate subpopulations of aerosol particles from a mixture of particles.

Abstract: A method and apparatus for gelling liquid propane and other liquefied gasses includes a temperature controlled churn mixer, vacuum pump, liquefied gas transfer tank, and means for measuring amount of material entering the mixer. The apparatus and method are particularly useful for the production of high quality rocket fuels and propellants.

Abstract: Methods and apparatus for the micro-scale, dielectrophoretic separation of particles are provided. Fluid suspensions of particles are sorted and separated by dielectrophoretic separation chambers that have at least two consecutive, electrically coupled planar electrodes separated by a gap in a fluid flow channel. The gap distance as well as applied potential can be used to control the dielectrophoretic forces generated. Using consecutive, electrically coupled electrodes rather than electrically coupled opposing electrodes facilitates higher flow volumes and rates. The methods and apparatus can be used, for example, to sort living, damaged, diseased, and/or dead cells and functionalized or ligand-bound polymer beads for subsequent identification and/or analysis.

Abstract: A microfluidically-controlled transmission mode nanoscal surface plasmonics sensor device comprises one or more arrays of aligned nanochannels in fluid communication with inflowing and outflowing fluid handling manifolds that control the flow of fluid through the array(s). Fluid comprising a sample for analysis is moved from an inlet manifold, through the nanochannel array, and out through an exit manifold. The fluid may also contain a reagent used to modify the interior surfaces of the nanochannels, and/or a reagent required for the detection of an analyte.

Abstract: An apparatus and method for assaying blood-brain barrier properties for drug and drug delivery vehicle screening comprising of a microfluidic apparatus with gaps separating lumen and tissue space enabling formation of tight junctions similar to in vivo conditions using endothelial cells and brain cells.

Abstract: The present invention is a bi-propellant system comprising a gelled liquid propane (GLP) fuel and a gelled MON-30 (70% N2O4+30% NO) oxidizer. The bi-propellant system is particularly well-suited for outer planet missions greater than 3 AU from the sun and also functions in earth and near earth environments. Additives such as powders of boron, carbon, lithium, and/or aluminum can be added to the fuel component to improve performance or enhance hypergolicity. The gelling agent can be silicon dioxide, clay, carbon, or organic or inorganic polymers. The bi-propellant system may be, but need not be, hypergolic.

Abstract: The growth temperature of carbon nanotubes on a catalyst distributed on a substrate is reduced by controlling graphene layer formation on the catalyst and catalyst deactivation by catalytic oxidation.

Abstract: A method and apparatus for gelling liquid propane and other liquefied gasses includes a temperature controlled churn mixer, vacuum pump, liquefied gas transfer tank, and means for measuring amount of material entering the mixer. The apparatus and method are particularly useful for the production of high quality rocket fuels and propellants.

Abstract: The present invention is an ultrasonic thrombectomy catheter that produces physical forces (shear rates) strong enough to emulsify obstructions such as thrombi and emboli without causing damage to arterial walls. This is accomplished by properly arranging piezoelectric transducers within a catheter and a tubular catheter head separated by a gap to generate acoustic streaming that simultaneously emulsifies the obstruction and sweeps resulting debris into a catheter lumen for removal. The open gap may be formed by supporting struts that connect the catheter to the catheter head. The design of the catheter tip allows the fabrication of catheters capable of removing partial or complete blockages from arteries and other vessels having diameters as small as 2 mm.

Abstract: The present invention is a method and apparatus for gelling liquid propane and other liquefied gasses. The apparatus includes a temperature controlled churn mixer, vacuum pump, liquefied gas transfer tank, and means for measuring amount of material entering the mixer. The method uses gelling agents such as silicon dioxide, clay, carbon, or organic or inorganic polymers, as well as dopants such as titanium, aluminum, and boron powders. The apparatus and method are particularly useful for the production of high quality rocket fuels and propellants.

Abstract: The present invention is a catalytic chemical vapor deposition method and apparatus for synthesizing carbon nanotubes and/or carbon nanofibers (CNTs) on a substrate by selectively heating a catalyst for CNT synthesis on or near the surface of the substrate. Selective heating of the catalyst is achieved using an exothermic oxidation reaction on the surface of the catalyst. Selective heating of the catalyst prevents heating of the substrate and enables the synthesis of CNTs on temperature sensitive substrates.

Abstract: The present invention is a method comprising a direct chirality-selective nucleation and synthesis of single-walled carbon nanotubes from carbon-containing gases using catalytic nanoparticles of uniform size heated by ultra-short laser pulses of selected frequency to temperatures sufficient for carbon nanotube nucleation and synthesis.

Abstract: A method for characterizing particle adhesion in microfluidic bifurcations and junctions comprises at least one idealized bifurcation or junction. Multiple bifurcations and/or junctions can be combined on a single microfluidic chip to create microfluidic networks configured for assays specifically to characterize particle interactions at junctions or to screen particles for desired interactions with microfluidic bifurcations and/or junctions.

Abstract: The present invention is a synthetic microfluidic microvasculature network and associated methods. The synthetic microfluidic microvasculature network mimics the structure, fluid flow characteristics, and physiological behavior of physiological microvasculature networks. Computational methods for simulating flow and particle adherence in synthetic and physiological microvascular systems and methods for determining parameters influencing particle adhesion and drug delivery are also described. The invention has many uses including the optimization of drug delivery and microvascular treatments and in describing disease mechanisms that affect the microvasculature such as inflammation, diabetes and hypertension.

Abstract: A microfluidic cartridge for isolating biological molecules having a capture chamber containing functionalized solid supports maintained in a fluidized state provides reduced pressure drops and bubble formation during microfluidic extraction. The cartridge may include an electric field lysis chamber and/or a chemical lysis chamber. The electric-field lysis chamber may comprise an electrically insulating structure arranged between two opposing planar electrodes.

Abstract: An apparatus and method for identifying and screening for agents affecting the leukocyte adhesion cascade (LAC) encompassing rolling, adhesion and migration comprises an optically clear, plastic microfluidic chip comprising flow channels with diameters in the range of 10-500 ?m. The flow channels are coated with endothelial cells and at least a portion of the flow channels contains 1-30 ?m sized openings, optionally filled with a native or synthetic extracellular matrix, that allow leukocyte migration into one or more tissue spaces.

Abstract: An apparatus and method for assaying a tumor drug delivery vehicle comprises a synthetic microvascular network of interconnected flow channels in fluid communication through a porous wall with a tissue space containing animal cells and means for quantifying drug delivery from the microvascular network to the animal cells.

Abstract: Apparatus and methods are disclosed for mixing and self-cleaning elements in microfluidic systems based on electrothermally induced fluid flow. The apparatus and methods provide for the control of fluid flow in and between components in a microfluidic system to cause the removal of unwanted liquids and particulates or mixing of liquids. The geometry and position of electrodes is adjusted to generate a temperature gradient in the liquid, thereby causing a non-uniform distribution of dielectric properties within the liquid. The dielectric non-uniformity produces a body force and flow in the solution, which is controlled by element and electrode geometries, electrode placement, and the frequency and waveform of the applied voltage.