2284results about "Analysing fluids using sonic/ultrasonic/infrasonic waves" patented technology

Items of mail are rapidly processed in a mail sampling system to determine if the mail is contaminated with a chemical or biological agent. The mail sampling system maintains a negative pressure in a containment chamber and includes a triggering sampler that makes a threshold determination regarding possible contamination, and a detecting sampler that obtains a sample for more detailed analysis in response to a signal from the triggering sampler. A sample of particulates collected from an item of mail is either removed for analysis or analyzed in the system to identify a contaminating agent. Optionally, the system includes an archiving sampler, which archives samples for subsequent processing and analysis, and a decontamination system, which is activated to decontaminate the mail if needed.

A method for the detection of analytes using resonant mass sensors or sensor arrays comprises frequency encoding each sensor element, acquiring a time-domain resonance signal from the sensor or sensor array as it is exposed to analyte, detecting change in the frequency or resonant properties of each sensor element using a Fourier transform or other spectral analysis method, and classifying, identifying, and/or quantifying analyte using an appropriate data analysis procedure. Frequency encoded sensors or sensor arrays comprise sensor elements with frequency domain resonance signals that can be uniquely identified under a defined range of operating conditions. Frequency encoding can be realized either by fabricating individual sensor elements with unique resonant frequencies or by tuning or modifying identical resonant devices to unique frequencies by adding or removing mass from individual sensor elements. The array of sensor elements comprises multiple resonant structures that may have identical or unique sensing layers. The sensing layers influence the sensor elements' response to analyte. Time-domain signal is acquired, typically in a single data acquisition channel, and typically using either (1) a pulsed excitation followed by acquisition of the free oscillatory decay of the entire array or (2) a rapid scan acquisition of signal from the entire array in a direct or heterodyne configuration. Spectrum analysis of the time domain data is typically accomplished with Fourier transform analysis. The methods and sensor arrays of the invention enable rapid and sensitive analyte detection, classification and/or identification of complex mixtures and unknown compounds, and quantification of known analytes, using sensor element design and signal detection hardware that are robust, simple and low cost.

A gaseous fluorine detection system is provided which includes a generally enclosed sample cell containing a substrate comprising a material which interacts with fluorine gas to generate radiant energy. A gas sample of fluorine, the concentration levels of which are to be evaluated is flowed through the cell. A photomultiplier tube is positioned to receive the resulting radiant energy and generate an electrical output signal related to the level of said radiant energy. Means are provided for measuring the said photomultiplier output signal and relating same to the fluorine concentration of the gas sample provided to the cell.

A system for determining the density, flow velocity, and mass flow of a fluid comprising at least one sing-around circuit that determines the velocity of a signal in the fluid and that is correlatable to a database for the fluid. A system for determining flow velocity uses two of the inventive circuits with directional transmitters and receivers, one of which is set at an angle to the direction of flow that is different from the others.

Methods and systems for analyzing samples, such as gas samples, are described. One method comprises providing a gas sample, increasing pressure applied to the gas sample to compress the sample to a smaller volume and provide a pneumatically focused gas sample, and analyzing the pneumatically focused gas sample using any of a variety of analytical techniques. Also disclosed are systems for gas analysis, including systems for analysis of pneumatically focused, and thereby concentrated, gas samples and for analysis of particulate matter in gas samples. Analytical systems constructed within personal computer cases also are disclosed.

A system, method, and apparatus for detecting at least one condition of interest relating to a tube, e.g. the presence of an air bubble. In some embodiments, the sensor includes antennas, a split-ring resonator, a frequency generator capable of generating frequencies in the microwave range, and a detection component. The detection component may estimate at least one parameter of received microwave energy in order to determine if a condition of interest exists.

The present invention includes a method and apparatus for detecting use of illicit substances by analyzing a sample of breath using electronic sensor technology, including surface acoustic-wave gas sensor technology. The method determines the presence and concentration of the substance (or a class of substances). Diagnostic software is used to identify substances where a stored library of signatures is compared to the signature obtained from the system. Signal processing and neural networks are preferably utilized in the analysis.

Disclosed is a piezoelectric resonator, a process for the fabrication thereof and its use as a sensor element, which implemented in a through-flow cell, is integratable in a measurement system for the determination of the concentration of a substance contained in a liquid and/or for the determination of the physical properties of the liquid. The piezoelectric resonator is designed plane and is provided on its surface with electric contact areas for an electrode and a counter electrode, which is connectable to a signal source as well as to a measurement device. For measuring, the piezoelectric resonator is brought into contact with the to-be-examined liquid on one side, with the resonator responding to the accumulation of the mass of the to-be-detected substance or to a change in the physical properties of the liquid by changing its resonance frequency and/or oscillation amplitude.The present invention is distinguished by the fact that the piezoelectric resonator is provided with contact electrode areas which is contactable from one single side of the resonator. The resonator is the heart piece of a sensor element, which is integrated in a through-flow cell. The through-flow cell us insertable module-like in a measurement arrangement for determining the concentration of a substance contained in a liquid and/or determining the physical properties of the liquid.

In some embodiments, an oxygen concentrator may include lightweight injection molded housing components coupled to dual-pump diaphragm compressors. The oxygen concentrator may be coupled to a pressure transducer that detects a user's inhalation. The detected inhalation may signal the release of a bolus of oxygen. The sensitivity of the pressure transducer readings may be adjusted based on a detected environment. The user's breathing rate may also be determined to control the number of compressors used for increased efficiency. An ultrasonic sensor and gas flow rate meter may be used to determine an amount of oxygen being delivered to the user. Other components such as step valves and a solar panel may also be used to further conserve battery power. The oxygen concentrator may also incorporate an audio device such as a mobile phone.

The invention provides a system and method comprising an apparatus for removing contaminants from a gas in a semiconductor processing device, which can include a filter unit having at least two parallel filter stages located therein. The filter stages are designed to remove a least a portion of the contaminants present in the gas flowing through them. The apparatus can also include a flow controller for distributing the gas flow among the filter stages. In one embodiment, the controller may consist of a diffuser plate. The invention also provides a sampling tube orifice for gas flow control in a system or method of the invention. In another embodiment, an apparatus for removing contaminants from a gas in a clean room comprises a filter unit having at least two parallel filter stages, which are used to remove a portion of the contaminants in the gas as it passes through the apparatus.

The invention relates to a device for manipulation of particles (30) in a sample liquid (32) said device comprising a source of ultrasound (16) capable of emitting ultrasound with a given wavelength, an inlet for a sample liquid (2), one or more outlets (4, 5, 6) and a compartment (14), being dimensioned to support a standing ultrasonic wave (40) of said wavelength, characterised in that the device further comprises an inlet for sheath liquid (1, 3) configured to direct a sheath liquid (34) to extend substantially in parallel to an anti-node plane (46) of the ultrasonic standing wave (40) proximate to a sheathed compartment wall. Specifically the device may be used in combination with a particle enumeration device for enumeration of somatic cells in milk.

An imaging method for observing the propagation of a shear wave simultaneously at a multitude of points in a diffusing viscoelastic medium. The shear wave is caused to be generated by firing at least one focused ultrasound compression wave into the viscoelastic medium by means of an array of transducers, and then emitting at a fast rate and using the same array of transducers, unfocused ultrasound compression waves serving to obtain a succession of images of the medium, and processing the images obtained in this way in deferred time in order to determine the movements of the medium during the propagation of the shear wave.

The fouling state of a polymeric membrane within the high pressure housing of a spiral wound or a hollow fiber membrane module is determined. An ultra sonic transducer positioned with its emitting face in physical engagement with the outer surface of the housing is pulse energized by a pulser/receiver device. A membrane echo signal is detected by a receiver of the pulser/receiver device. A reference echo signal indicative of a fouled or an unfouled state of the membrane is compared to the echo signal to determine the membrane fouling state. The echo to reference comparing step can be based upon comparing amplitude domain signals, comparing time-domain signals, comparing combinations of amplitude domain and time-domain signals, and comparing transformations of amplitude domain and time-domain signals. A clean or a fouled reference echo can be provided from a clean or a fouled membrane and then stored for use during a liquid separation process, or a clean reference echo signal can be obtained on-line from a second transducer whose echo signal is derived from an area of the membrane known to remain relatively unfouled during the liquid separation process, or a clean or fouled reference echo signal can be provided for later use during a cleaning process or during a liquid separation process. Multiple transducers and a switching network can sample the fouling state at different positions within the membrane module.

The present invention relates generally to methods and compositions for analyzing test samples containing target analytes including proteins and nucleic acids. The invention uses a surface acoustic wave sensor in combination with a hydrogel to obtain an ultra sensitive non-fluorescent detection system.

A housing for a sensor to prevent condensate from collecting in the sensor. The housing includes a deflector to channel condensate forming in the housing away from the sensor. A notch is provided at the base of the sensor to ensure any condensate forming on the sensor itself does not collect at the sensor base. Further the interior of the housing is roughened and treated with an antifogging agent to ensure any condensate falls continuously so droplets do not form.

A sensor device for detecting the presence of a gas species in a gas environment susceptible to the presence of same. The sensor device may include a piezoelectric crystal coated with a sensor material having adsorptive affinity for the gas species, with an electric oscillator arranged for applying an oscillating electric field to the piezoelectric crystal to generate an output frequency therefrom indicative of the presence of the gas species when present in the gas environment, when the gas environment is exposed to the piezoelectric crystal. Another aspect of the invention involves a porous polymeric material that may be employed as a sensor material on a piezoelectric crystal sensor device, as well as a quartz microbalance holder that enables reactor gas monitoring. The sensor device alternatively may comprise an optical sensor arranged in a non-contaminating fashion in relation to the gas environment being monitored.

A chemical-sensing apparatus is formed from the combination of a chemical preconcentrator which sorbs and concentrates particular volatile organic chemicals (VOCs) and one or more chemiresistors that sense the VOCs after the preconcentrator has been triggered to release them in concentrated form. Use of the preconcentrator and chemiresistor(s) in combination allows the VOCs to be detected at lower concentration than would be possible using the chemiresistor(s) alone and further allows measurements to be made in a variety of fluids, including liquids (e.g. groundwater). Additionally, the apparatus provides a new mode of operation for sensing VOCs based on the measurement of decay time constants, and a method for background correction to improve measurement precision.

The present invention provides methods for detecting the presence of an analyte indicative of various medical conditions, including halitosis, periodontal disease and other diseases are also disclosed.

A chemical sensing system has: an interrogation unit operable to wirelessly transmit an interrogation signal and wirelessly receive a response; an environmentally sealed container for holding a chemical analyte; a sensor array unit in fluid communication with the analyte disposed within the container, where the sensor array unit is operable to generate a response in the presence of a chemical stimulus; and a passive responder unit connected with the sensor array unit, the responder unit being powered from the interrogation signal, where the responder unit is operable to wirelessly receive the interrogation signal and wirelessly transmit the response to the interrogation signal to the interrogation unit.

A sensor arrangement for ascertaining the density and the viscosity of a liquid is proposed, having an arrangement comprising at least two basic sensor elements, at least one of which can be wetted with the liquid, and having electro-acoustical transducers (6) in the basic sensor elements for generating and detecting surface acoustic waves with predetermined wave modes, from whose propagation behavior along a measurement path a measure for the density and the viscosity of the liquid can be ascertained. Liquid traps (17) for the liquid, which extend in the applicable measurement path, are disposed in the region of at least one of the basic sensor elements, parallel to the direction of propagation of the surface acoustic wave.