Enertechnix, Inc.

Other

University of Washington

Spectree, LLC

Igor V Novosselov

Peter C Ariessohn

Evan D Dengler

Michelle Hickner

Tomas Njalsson

A method includes receiving input indicating at least two of: (a) a coefficient of first sensitivity of an optical particle sizer (OPS) to a real part of a complex refractive index (CRI); (b) a coefficient of second sensitivity of the OPS to an imaginary part of the CRI; (c) a coefficient of a degree of monotonicity between intensity and particle size; (d) a coefficient of a dynamic range of the OPS; or (e) a coefficient of a limit of detection (LOD) of the OPS; determining ratings for the OPS using the at least two of (a)-(e) and at least two of (i) the first sensitivity, (ii) the second sensitivity, (iii) the degree of monotonicity, (iv) the dynamic range, or (v) the LOD; identifying an angle that corresponds to a maximum or minimum rating; and providing an OPS having a detection angle that is within 5 degrees of the identified angle.

Method for determining detection angle of optical particle sizer

A non-contact aerodynamic sampling tool for collecting particles and vapors from the surfaces. Opposing planar jets or planar jet arrays are used to liberate material from surfaces so that particulate matter and vapors can be collected for analysis in real time. High-speed valves may be triggered to create pressure waveforms for high velocity pressurized planar jet bursts, or continuously operated opposing wall jets may be angularly directed toward a target surface, permitting sampling from large standoff distances. The wall jets traverse the surface and exhibit significant drag forces to lift particles into a suction intake. Unlike axisymmetric jets, the wall jets sustain the flow momentum over the target surface for a greater distance, dislodging particles submerged in the boundary layer and significantly improving particle resuspension and vapor collection. Real-time analysis and detection of target analytes are achieved by efficient sample liberation from the surface in the sampling tool and the efficient sample delivery to an analytical module.

Aerodynamic sampling of particles and vapors from surfaces for real-time analysis

A non-contacting aerodynamic jet tool for collecting particles and vapors associated with surfaces. Opposing planar jets or planar jet arrays are used to liberate material from surfaces so that resuspended particulate matter and vapors can be collected for analysis. In operation, high-speed valves are triggered to create waveforms of high velocity pressurized planar jet bursts. The wall jets that traverse the surfaces exhibit unexpectedly high wall surface stress with velocity spikes characteristic of a chain of shock waves. Unlike axisymmetric jets, the wall jet tool flows over the target surface for a greater distance with wall shear stress having sufficient momentum to dislodge particles submerged in the boundary layer, dramatically improving sampling efficiency by lifting the particles and vapors from the boundary layer into a sampling intake for downstream analysis.

Pulsed jet sampling of particles and vapors from substrates

Apparatus and methods for selectively separating a volatile constituent of a particle from a gas stream for analysis. Particles are separated from bulk flow by inertia and impacted in a cavity containing a small but stable vortex or eddy. Heat is applied to volatilize constituents of the particles. The gas entrained within the vortex, which exchanges only slowly with the bulk flow, is withdrawn for analysis. In this way, a high volume flow containing particles of interest is reduced to a low volume flow containing a vapor concentrate. Advantageously, the apparatus may be operated at very low pressure drops in fully continuous, semi-continuous or batch mode according to the requirements of the downstream analytical unit. The apparatus finds use in active surveillance, such as in use of aerosols to detect explosives or chemical residues on persons, vehicles or luggage in real time.

Trapped vortex particle-to-vapor converter

Devices, apparatus and methods are disclosed for non-contact pneumatic sampling and sampling of surfaces, persons, articles of clothing, buildings, furnishings, vehicles, baggage, packages, mail, and the like, for contaminating aerosols indicative of a hazard or a benefit, where the contaminating aerosols are chemical, radiological, biological, toxic, or infectious in character. In a first device, a central orifice for pulling a suction gas stream is surrounded by a peripheral array of convergingly-directed gas jets, forming a virtual sampling chamber. The gas jets are configured to deliver millisecond pneumatic pulses that erode particles from solid surfaces at a distance. In another aspect of the invention, a suction gas stream is split using an air-to-air concentrator so that a particle-enriched gas flow is directed to a particle trap and any particles immobilized in the particle trap (including any adsorbed vapors associated with the particles) are selectively analyzed to detect trace residues associated with explosives.

Particle interrogation devices and methods

An apparatus or device for collecting aerosol particles from a gas stream, having a collector body enclosing a collector channel, a particle trap in the collector channel, and an injection duct for injecting a discrete microdroplet of an elution reagent. The particle trap may be a centrifugal impactor, a bluff body impactor, or an electrostatic impactor. Aerosol particles are deposited on the surface during collection and are subsequently eluted with a microdroplet or a series of microdroplets as a concentrated liquid sample so that the sample can be analyzed in situ or conveyed to a detector for analysis. The collector serves as an aerosol-to-liquid conversion module as part of an apparatus for detecting and analyzing aerosol particles, and may be used in an integrated environmental threat assessment system, for example for characterization of aerosolized chemical and biological weapons, or for industrial or environmental monitoring.

Aerosol collection apparatus and methods

An aerosol sampling intake configured to exclude particles generally greater than 20 microns AD and capture particles of less than about 10 microns AD with high efficiency, independent of weather conditions, through which air is sampled by suction. The intake combines an omnidirectional horizontal segment with diffuser and elbow, the elbow transitioning flow to a vertical segment, the vertical segment with overhanging lip, the centrifugal impactor for self-cleaning operation, thus relieving the dual problems of re-entrainment of particles bouncing from the impactor surface and fouling by particles sticking to the impactor surface. The device is adapted for use on moving vehicles, for sampling at increased windspeeds, or for sampling in rain.

Omnidirectional aerosol sampling intake

Devices and methods are disclosed for non-contact pneumatic sampling of surfaces, persons, articles of clothing, buildings, furnishings, vehicles, baggage, packages, mail, and the like, for aerosols or vapor residues indicative of a hazard or a benefit, where the residues are chemical, radiological, biological, toxic, or infectious in character. A central orifice for pulling a vacuum is surrounded by an array of convergingly-directed gas jets, forming a 'virtual sampling chamber'. The gas jets are configured to deliver millisecond pneumatic pulses that erode particles and vapors from solid surfaces at a distance. A curtain wall flow encloses the sampling area during pulse retrieval.

A skimmer device for concentrating an aerosol from a flowing gas stream, having an inlet with inlet aperture and inlet raceway, an outlet with virtual impact void and collector channel, and bulk flow divertors symmetrically disposed on either side of the long axis of flow, further characterized in that the downstream walls of the bulk flow divertors are concavedly curved and reverse the direction of bulk flow. In section, the four channels or passages of the 'skimmer' thus form a 'crossed tee' with concavedly contoured lateral arms curving back around. The lateral flow channels are for diverting the bulk flow into exhaust chimney spaces, and the chimney spaces are positioned proximate to the inlet element and anterior to the collection channel. In operation, the bulk flow streamlines are thereby folded more than 90 degrees away from the long axis of flow on the laterally disposed concave walls of the bulk flow channels. While counterintuitive, this was found using computational fluid dynamics (CFD) and experimentation to dramatically reduce wall separation and related instabilities and to improve particle recoveries. Large two-dimensional arrays of closely stacked inlet and skimmer elements are thus achieved by fitting the chimneys into spaces between parallel inlet elements. The interlinked problems of flow instability, manufacturability of arrays, and scale-up of chimney cross-sectional area to equalize pressure differentials in the bulk flow diverter exhaust ducts, particularly in two-dimensional arrays at high throughput, are uniquely solved with this geometry.

Growing community of inventors

Seattle, WA, United States of America

Igor V Novosselov