Abstract: A system for determining properties of settling suspensions includes a settling container, a mixer, and devices for ultrasonic interrogation transverse to the settling direction. A computer system controls operation of the mixer and the interrogation devices and records the response to the interrogating as a function of settling time, which is then used to determine suspension properties. Attenuation versus settling time for dilute suspensions, such as dilute wood pulp suspension, exhibits a peak at different settling times for suspensions having different properties, and the location of this peak is used as one mechanism for characterizing suspensions. Alternatively or in addition, a plurality of ultrasound receivers are arranged at different angles to a common transmitter to receive scattering responses at a variety of angles during particle settling. Angular differences in scattering as a function of settling time are also used to characterize the suspension.

Abstract: An apparatus and method is described for measuring properties of bubbles from which certain physical characteristics of the liquid in which the bubbles are generated can be determined. The evolution of a bubble includes (1) formation and growth at a nozzle disposed within the liquid through which a gas is flowed, or formation and growth as a result of cavitation in the liquid from the application of focused acoustic energy to a location within the liquid; (2) detachment and resonance; and (3) rise towards terminal velocity. Measurements of the resonance frequency, the shape oscillation frequency and the terminal velocity of the bubble allow the determination of the density and surface tension of the liquid and the radius of the bubble.

Abstract: A method and apparatus for determining the composition of a containerized material, typically a suspension, through which ultrasonic waves are passed. The component ratios and particle sizes of a stationary or flowing material are determined by measuring ultrasonic wave phase and attenuation changes at multiple frequencies and deriving shape features from curves of the phase or attenuation versus frequency. Preferably, the frequency range employed extends below and above the frequency of maximum attenuation of the expected mean particle size in a suspension. The material composition is derived from analysis of the shape features of the derived curves.

Abstract: The invention provides a method and an apparatus for measuring the size, concentration and size distribution of particles in a fluid by determining the characteristics of an acoustic speckle signal of the particles and relating these characteristics to the size and concentration characteristics of the particles. The method and the apparatus are especially useful for the measurement of the size distribution of small particles in optically opaque liquids.

Abstract: The invention provides a method and an apparatus for measuring the size, concentration and size distribution of particles in a fluid by determining the characteristics of an acoustic speckle signal of the particles and relating these characteristics to the size and concentration characteristics of the particles. The method and the apparatus are especially useful for the measurement of the size distribution of small particles in optically opaque liquids.

Abstract: A particle size distribution monitor, comprising: a transducer adapted to be a source of ultrasonic energy and positioned in contact with a suspension containing a percent by volume of particles in a liquid, the transducer transmitting ultrasonic energy through the suspension wherein the energy comprises a wideband pulse containing a range of frequency components; a transducer adapted to be a receiver of ultrasonic energy and positioned in contact with said suspension to receive said wideband range of ultrasonic energy which has passed through the suspension; a first means adapted to accept a signal from said receiver and make an instantaneous determination of the attenuation of the wideband ultrasonic energy in passing through the suspension.

Abstract: An acoustic monitoring method and system in laser-induced optical breakdown (LIOB) provides information which characterize material which is broken down, microbubbles in the material, and/or the microenvironment of the microbubbles. In one embodiment of the invention, femtosecond laser pulses are focused just inside the surface of a volume of aqueous solution which may include dendrimer nanocomposite (DNC) particles. A tightly focused, high frequency, single-element ultrasonic transducer is positioned such that its focus coincides axially and laterally with this laser focus. When optical breakdown occurs, a microbubble forms and a shock or pressure wave is emitted (i.e., acoustic emission). In addition to this acoustic signal, the microbubble may be actively probed with pulse-echo measurements from the same transducer. After the microbubble forms, received pulse-echo signals have an extra pulse, describing the microbubble location and providing a measure of axial microbubble size.

Abstract: The invention provides a method and an apparatus for measuring the size, concentration and size distribution of particles in a fluid by determining the characteristics of an acoustic speckle signal of the particles and relating these characteristics to the size and concentration characteristics of the particles. The method and the apparatus are especially useful for the measurement of the size distribution of small particles in optically opaque liquids.

Abstract: The invention provides a method and an apparatus for measuring the size, concentration and size distribution of particles in a fluid by determining the characteristics of an acoustic speckle signal of the particles and relating these characteristics to the size and concentration characteristics of the particles. The method and the apparatus are especially useful for the measurement of the size distribution of small particles in optically opaque liquids.

Abstract: A method for manufacturing a flexural plate wave sensor including the steps of depositing a sacrificial material layer over a silicon substrate, depositing a membrane layer over the sacrificial material layer with the membrane layer covering the sacrificial material layer and contacting the silicon substrate, depositing a piezoelectric layer over the membrane layer, forming a first transducer on the piezoelectric layer, forming a second transducer on the piezoelectric layer, spaced from the first transducer, removing the sacrificial material layer to expose a portion of the membrane layer, and depositing an absorptive coating on the exposed portion of the membrane layer.

Abstract: A method and an apparatus for characterizing the barrier properties of an array of coatings. The method including providing a plurality of acoustic wave devices, wherein each of the plurality of acoustic wave devices comprises at least one surface, and providing a plurality of coating materials suitable for forming a plurality of coatings on the at least one surface of each of the plurality of acoustic wave devices. The method also including coating each of the plurality of acoustic wave devices with at least one of the plurality of coating materials to form a plurality of coated acoustic wave devices and measuring a predetermined output parameter of each of the plurality of coated acoustic wave devices.

Abstract: In a well bore operation in which a particulate is added to a fluid stream, a method of determining the concentration of said particulate in said fluid stream comprising the steps of measuring the rate of flow of the fluid stream, determining the rate of particulate flow in the fluid stream using an acoustic sensor and calculating the concentration of particulate in the fluid stream using results from the measuring and determining steps.

Abstract: Apparatus for determining the density of a fluid downhole includes apparatus for measuring compressibility of the fluid and apparatus for determining the speed of sound through the fluid. According to the methods of the invention, density of the fluid is calculated based upon the relationship between density, compressibility, and the speed of sound through the fluid.

Abstract: An apparatus that is configured to sense the presence of gases, vapors and liquids using acoustic waves. The apparatus comprises a first part that is configured to generate acoustic waves. The apparatus further comprises a second part having a sensing and acoustic wave guiding device, which is configured to sense the presence of such substances and propagate acoustic waves. The first part is removably fixable to the second part of the apparatus. When the first part is fixed to the second part, the acoustic waves propagate in the second part.

Abstract: A bubble detector utilizes an ultrasonic transducer to sample bubbles as they pass the transducer. The envelope of the return signal is analyzed to determine the volume of each sampled bubble. If the total volume of bubbles sampled within a certain period of time exceeds a desired maximum volume, the bubble detector may initiate a system shut down. A bubble detector can be evaluated or calibrated by introducing bubbles into a conduit, detecting the bubbles introduced into the conduit using visual inspection or a bubble detector of known resolution and comparing the results with the examination of a bubble detector under evaluation.

Abstract: An acoustic measurement system detects solids within a fluid includes a sample cell 10 for containing the fluid, a first transducer 20 for outputting a first acoustic detection signal at a first frequency, a first acoustic receiver 20 responsive to the first acoustic detection signal, and a second acoustic transducer 20 for outputting an acoustic second mixing signal at a second frequency to mix the solids in the fluid within the sample cell. Controller 40 may vary the “on” time of the second transducer with respect to the measurement of the first acoustic signal. The fluid within the cell may be tested under a wide range of temperatures and pressures. The acoustic measurement system may also be used to measure the bulk modulus of the liquid. The method of the invention allows for the detection of crystallization for a portion of the fluid in the sample cell under widely varying conditions.

Abstract: A device for use in determining the characteristics of particles dispersed in a medium is described. The device has a sample cell for holding a sample containing particles dispersed in a medium. A transducer is positioned to emit sound waves into the sample of the sample cell. A mirror surface is positioned for translational movement within the sample cell without changing the level of the sample in the cell, for movement without the use of dynamic o-ring seals, and is positioned to reflect sound waves emitted by the transducer.

Abstract: A method including: sonicating a liquid suspension of first particles; and analyzing the liquid phase for second particles. An apparatus including: a sonicator adapted to sonicate a liquid suspension of first particles; and a first analyzer adapted to analyze the sonicated liquid phase for second particles. The method and apparatus can be used to analyze the adhesion force relationships between the main or host first particles and guest or surface additive second particles.

Abstract: The invention provides a method and an apparatus for measuring the size, concentration and size distribution of particles in a fluid by determining the characteristics of an acoustic speckle signal of the particles and relating these characteristics to the size and concentration characteristics of the particles. The method and the apparatus are especially useful for the measurement of the size distribution of small particles in optically opaque liquids.

Abstract: The invention provides a method and an apparatus for measuring the size, concentration and size distribution of particles in a fluid by determining the characteristics of an acoustic speckle signal of the particles and relating these characteristics to the size and concentration characteristics of the particles. The method and the apparatus are especially useful for the measurement of the size distribution of small particles in optically opaque liquids.

Abstract: A method including: sonicating a liquid suspension of first particles; and analyzing the liquid phase for second particles. An apparatus including: a sonicator adapted to sonicate a liquid suspension of first particles; and a first analyzer adapted to analyze the sonicated liquid phase for second particles. The method and apparatus can be used to analyze the adhesion force relationships between the main or host first particles and guest or surface additive second particles.

Abstract: A cavitation sensor includes an ultrasonically absorbent coating (20) disposed around a piezoelectric element (30) and a conduit (25). The conduit (25) includes a boundary delimited by the piezoelectric element (30), while the ultrasonically absorbent coating (20) is substantially transparent to acoustic driving field frequencies. The sensor is more accurate than prior art sensors.

Abstract: A method and apparatus for measuring properties of a fluid composition in a conduit includes a mechanical resonator connected to a measurement circuit. The measurement circuit provides a variable frequency input signal to the mechanical resonator, causing the mechanical resonator to oscillate. The input signal is then sent to the mechanical resonator and swept over a selected frequency range. The mechanical resonator's response over the frequency range depends on various characteristics of the fluid being tested, such as the temperature, viscosity, and other physical properties.

Abstract: A method is described which applies Acoustic Spectrometry to characterize both the particle size distribution and mechanical properties of the soft particles in concentrated dispersed systems. It is shown that compressibility of the soft particles can be calculated from the measured sound speed using well-known Wood expression. The value of the thermal expansion coefficient can be calculated from the measured attenuation spectra either for known particle size or together with particle size as adjustable parameter.

Abstract: The invention provides a method and an apparatus for measuring the size, concentration and size distribution of particles in a fluid by determining the characteristics of an acoustic speckle signal of the particles and relating these characteristics to the size and concentration characteristics of the particles. The method and the apparatus are especially useful for the measurement of the size distribution of small particles in optically opaque liquids.

Abstract: A bubble detector utilizes an ultrasonic transducer to sample bubbles as they pass the transducer. The envelope of the return signal is analyzed to determine the volume of each sampled bubble. If the total volume of bubbles sampled within a certain period of time exceeds a desired maximum volume, the bubble detector may initiate a system shut down. A bubble detector can be evaluated or calibrated by introducing bubbles into a conduit, detecting the bubbles introduced into the conduit using visual inspection or a bubble detector of known resolution and comparing the results with the examination of a bubble detector under evaluation.

Abstract: A device for use in determining the characteristics of particles dispersed in a medium is described. The device has a sample cell for holding a sample containing particles dispersed in a medium. A transducer is positioned to emit sound waves into the sample of the sample cell. A mirror surface is positioned for translational movement within the sample cell without changing the level of the sample in the cell, for movement without the use of dynamic o-ring seals, and is positioned to reflect sound waves emitted by the transducer.

Abstract: A ferromagnetic particle sensor includes a housing having a first electromagnet and a second electromagnet attached to the interior surface thereof. A mass sensitive surface acoustic wave (SAW) sensor is disposed between the electromagnets. The sensor is submerged in lubricating fluid and as the electromagnets are energized they produce magnetic forces that draw fluid-borne ferromagnetic particles past the SAW sensor. The SAW sensor is used measure the mass of the ferromagnetic particles and determine when the volume of particles in the lubricating fluid increases.

Abstract: The ultrasonic sensor comprises an ultrasonic transmitter (11) and an ultrasonic receiver (12) between which an accommodating device (13) for a hose (14) is arranged. The hose is flattened between stamps (21, 22) thus being pressed against rigid concave forming areas (15, 16) where the hose bears in a gap-free manner upon the housing wall (17). The sound velocity in the housing (10) is approximately as large as in the material of the hose (14). In the liquid contained in the hose the sound velocity is considerably smaller. Parallel sound waves are refracted at the interface between hose material and liquid such that the sound waves converge. By concentrating the sound energy into the hose and onto the ultrasonic receiver (12) a high-energy received signal is generated. When air bubbles exist in the liquid, the received signal is attenuated.

Abstract: An ultrasonic probe and method for noninvasively monitoring materials processing in screw driven extruders. The noninvasive probe includes at least one ultrasonic transducer operable to transmit an ultrasonic signal on a signal path intersecting an inner sidewall of a barrel of the extruder and material between the inner sidewall of the barrel and an outer surface of a screw within the barrel. Information about the state of the material intersected by the ultrasonic signal is ascertainable from an elapsed time between reception of a first reflection of the ultrasonic signal and reception of a second reflection of the ultrasonic signal. The first reflection results when the ultrasonic signal exits the inner sidewall of the barrel and the second reflection results when the ultrasonic signal reaches one of the outer surface of the screw and partially solid material.

Abstract: A method is provided for analyzing suspended particulate and liquid medium in a fluid stream by transmitting acoustic signals into the fluid, detecting scattered acoustic energy, and determining a parameter related to the density and compressibility of the fluid. In one embodiment, the fluid analysis tool comprises two transmitting transducers intermittently emitting acoustic signals, and two receiving transducers being differently azimuthally positioned with respect to the transmitters. The ratio of the amplitude of scattered signals measured by the two receivers as a result of emission from the first and second transmitters are used to calculate the parameter. In another embodiment, a tool comprising one transmitter and at least three receivers with azimuthal angles in both forward and backward scattering regions with respect to the incident wave is disclosed. The scattering signal amplitudes normalized by the amplitude from one of the receivers is used to identify and monitor the system.

Abstract: Methods and apparatus for screening diverse arrays of materials are provided. In one aspect, systems and methods are provided for imaging a library of materials using ultrasonic imaging techniques. In another aspect, systems and methods are provided for generating acoustic waves in a tank filled with a coupling liquid to form a disturbance that is representative of a library of materials. In another aspect of the invention, a mechanical resonator is used to evaluate various properties (e.g., molecular weight, viscosity, specific weight, elasticity, dielectric constant, conductivity, etc.) of the individual liquid elements of a library of materials.

Abstract: A method and apparatus for measuring properties of a liquid composition includes a mechanical resonator, such as a thickness shear mode resonator or a tuning fork resonator, connected to a measurement circuit. The measurement circuit provides a variable frequency input signal to the tuning fork, causing the mechanical resonator to oscillate. To test the properties of a liquid composition, the mechanical resonator is placed inside a sample well containing a small amount of the liquid. The input signal is then sent to the mechanical resonator and swept over a selected frequency range, preferably less than 1 MHz to prevent the liquid being tested from exhibiting gel-like characteristics and causing false readings. The mechanical resonator's response over the frequency range depends on various characteristics of the liquid being tested, such as the temperature, viscosity, and other physical properties.

Abstract: There is provided a double-headed mass sensor (25) in which between a first connecting plate (22A) joined to a first diaphragm (21A) at respective sides and a second connecting plate (22B) joined to a second diaphragm (21B) at respective sides, a first sensing plate (41A), on which a main element (44) is provided on at least one plane surface, is bridged, and a resonating portion comprising the diaphragms (21A), (21B), the connecting plates (22A), (22B), the first sensing plate (41A) and the main element (44) is joined to a sensor substrate (27). Change in the mass of each of the diaphragms (21A), (21B) is measured by measuring change in the resonant frequency of the resonating portion accompanying the change in the mass of the diaphragms (21A), (21B). The mass sensor of the present invention enables the easy and highly accurate measurement of a minute mass of a nanogram order including microorganisms such as bacteria and viruses, chemical substances, and the thickness of vapor-deposited films.

Abstract: This invention is directed to a method and apparatus for measuring the rate of calcium oxalate scale formation in a continuously flowing solution having a pH of from about 2 to about 3 comprising measuring the rate of deposition of calcium oxalate scale from the solution on to a quartz crystal microbalance having a top side comprising a working electrode in contact with the solution and a second, bottom side isolated from the solution, wherein the pH of the solution proximate to the microbalance is measured using a pH measuring module and is controlled electrochemically at from about 3.5 to about 9 and wherein the working electrode is coated with or made of a conductive material on which the intensive evolution of hydrogen gas proceeds at potentials more negative than those necessary to achieve a pH of 3.5-9 proximate to the microbalance.

Abstract: Provided are a measurement apparatus and a measurement system comprising sample and reference microresonators, such as sample and reference quartz crystal microbalances; sample and reference heat flow sensors; and a heat sink coupled thermally to the heat flow sensors. These may be used to measure changes in one or more properties, such as mass, due to a liquid sample on a surface of a sample microresonator and also to measure heat flows from the sample on the surface of the sample microresonator by utilizing the heat flow sensors, which are coupled thermally to the corresponding sample or reference microresonators. Also provided is a method for measuring one or more properties, such as mass, of a liquid sample and the flow of heat from the sample to the heat sink by utilizing such apparatus.

Abstract: A ZrO2 porcelain comprising a cylindrical member and a flexible member made of a ZrO2 porcelain which has a relative density not lower than 95% and contains a cubic crystal at a ratio not lower than 75%, thereby exhibiting high erosion resistance and high strength.

Abstract: A method and apparatus for measuring properties of a fluid composition includes a mechanical resonator connected to a measurement circuit. The measurement circuit provides a variable frequency input signal to the mechanical resonator, causing the mechanical resonator to oscillate. To test the properties of a liquid composition, the mechanical resonator is placed inside a sample well containing a small amount of the fluid. The input signal is then sent to the mechanical resonator and swept over a selected frequency range. The mechanical resonator's response over the frequency range depends on various characteristics of the fluid being tested, such as the temperature, viscosity, and other physical properties. The invention is particularly suitable for combinatorial chemistry applications, which require rapid analysis of chemical properties for screening.

Abstract: A process and device are disclosed for recognizing foreign bodies in viscous or fluid masses with lumpy foodstuffs. The mass to be checked runs through a measurement section, in which, pulsed ultrasonic signals are emitted through the mass, are reflected after passing through the mass, and after passing again through the mass they are received and compared with the ultrasonic echo of the reflection surface. When the changes of the received signals exceed a predetermined threshold value, a warning or actuating signal is generated to interrupt mass advance. The parameters to be evaluated for the signal may be their amplitudes, as well as the speed of change of their amplitudes or the propagation times.

Abstract: An apparatus for use in a subterranean well includes a valve, a transducer and a circuit. The valve is adapted to propagate acoustic energy in response to a well fluid flow contacting the valve. The transducer is acoustically coupled to the valve and isolated from the flow to furnish an indication of the acoustic energy. The circuit is adapted to furnish signals to transmit stimuli indicative of the characteristic to a surface of the well based on the indication furnished by the transducer.

Abstract: A surface acoustic wave device sensor configured so as to have at least two different modes of operation. An acoustic response is obtained from each of the different modes of operation. The different modes of operation are a combination of a temperature effect and a measurand effect. The measurand effect is caused by the absorption and/or adsorption of a substance into a selective coating on the piezoelectric substrate. The two different modes of operation are effected differently by the temperature effect and therefore can be used to effectively eliminate the temperature effect by simultaneously solving equations representative of the different modes of operation. The present invention eliminates the need to provide other relatively more complicated temperature compensating structure or to maintain the device at a predetermined constant temperature. The present invention can be used to detect different chemicals or substances.

Abstract: A vapor sensing device that is sufficiently small and lightweight to be handheld, and also modular so as to allow the device to be conveniently adapted for use in sensing the presence and concentration of a wide variety of specified vapors as resulting from gases released during either decomposition and spoilage of food stuffs, or as released into either the breath or body fluids of a sick patient being medically diagnosed. The device provides these benefits using a sensor module that incorporates a sample chamber and a plurality of sensors located on a chip releasably carried within or adjacent to the sample chamber. Optionally, the sensor module can be configured to be releasably plugged into a receptacle formed in the device. Vapors are directed to pass through the sample chamber, whereupon the sensors provide a distinct combination of electrical signals in response to each.

Abstract: A sludge blanket level is determined in a waste water treatment clarifier using sonic pulse reflections. Additionally, using similar techniques, the clarity of the waste water is determined. A sonic pulse is directed into the waste water. Echos are generated as the pulse encounters the impedance mismatches indicative of changes in the density of the water. The echos are compensated for attenuation as a function of travel time through the water, energy lost due to prior peak reflections, and are processed to remove random signals using correlation techniques. A sludge blanket is selected from the compensated echo signal as a function of the size and location of echo peaks. Additionally, the clarity is determined as a function of the area under the echo signal between two points corresponding to predefined levels in the clarifier tank.

Abstract: Method and equipment for the detection and identification of particles in a suspension with the aid of acoustic signals, directed at at least one measurement volume within the suspension, via reception of acoustic reflection signals, conversion of the acoustic reflection signals into electrical reflection signals, counting the number of electrical reflection signals which have an amplitude in excess of a predetermined value and converting the count into numbers of particles which are larger than a certain size, at least one curve being composed on the basis of a cumulative count of the number of reflection signals which have an amplitude in excess of a specific value as a function of the amplitude and the at least one curve being compared with predetermined standard cumulative count curves and material properties, particle concentration, particle size distribution and/or particle characteristics, such as particle shape, particle size and standard deviation thereof, are deduced from the comparison.

Abstract: 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.

Abstract: Provided is a mass and heat flow measurement apparatus comprising sample and reference microresonators, such as sample and reference quartz crystal microbalances; sample and reference heat flow sensors, such as sample and reference isothermal heat conduction calorimeters; and sample and reference heat sinks coupled thermally to the heat flow sensors. The apparatus may be used to measure changes in mass due to a sample on a surface of the sample microresonator and also to measure heat flows from the sample on the surface of the sample microresonator by utilizing the heat flow sensors, which are coupled thermally to the corresponding sample or reference microresonators. Also provided is a method for measuring the mass of a sample and the flow of heat from the sample to the heat sink by utilizing such apparatus.

Abstract: Methods and apparatus for screening diverse arrays of materials are provided. In one aspect, systems and methods are provided for imaging a library of materials using ultrasonic imaging techniques. The system includes one or more devices for exciting an element of the library such that acoustic waves are propagated through, and from, the element. The acoustic waves propagated from the element are detected and processed to yield a visual image of the library element. The acoustic wave data can also be processed to obtain information about the elastic properties of the library element. In another aspect, systems and methods are provided for generating acoustic waves in a tank filled with a coupling liquid. The library of materials is then placed in the tank and the surface of the coupling liquid is scanned with a laser beam. The structure of the liquid surface disturbed by the acoustic wave is recorded, the recorded disturbance being representative of the physical structure of the library.

Abstract: An improved multi-element apparatus for detecting the presence of at least one chemical, biological or physical component in a monitored area comprising an array or single set of the following elements: a capacitive transducer having at least one cantilever spring element secured thereto, the cantilever element having an area thereof coated with a chemical having an affinity for the component to be detected; a pick-up plate positioned adjacent to the cantilever element at a distance such that a capacitance between the cantilever element and the pick-up plate changes as the distance between the cantilever element and the pick-up plate varies, the change in capacitance being a measurable variation; a detection means for measuring the measurable variation in the capacitance between the cantilever element and the pick-up plate that forms a measurement channel signal; and at least one feedback cantilever spring element positioned apart from the coated cantilever element, the cantilever element substantially unaffe