Abstract: A microfabricated mass-sensitive chemical preconcentrator actively measures the mass of a sample on an acoustic microbalance during the collection process. The microbalance comprises a chemically sensitive interface for collecting the sample thereon and an acoustic-based physical transducer that provides an electrical output that is proportional to the mass of the collected sample. The acoustic microbalance preferably comprises a pivot plate resonator. A resistive heating element can be disposed on the chemically sensitive interface to rapidly heat and release the collected sample for further analysis. Therefore, the mass-sensitive chemical preconcentrator can optimize the sample collection time prior to release to enable the rapid and accurate analysis of analytes by a microanalytical system.

Abstract: Piezoelectric plates conduct bending vibrations and are axially symmetrical about the vibration shaft so the piezoelectric plates conduct a bending vibration, lower vibrating ends of the piezoelectric plates are rigidly connected to a vibration suppressing member and upper vibration ends of the piezoelectric plates are rigidly connected to the vibration shaft, an inner edge of each of the piezoelectric plates excluding the vibration connection part is free of the vibration shaft, a bending vibration at the lower vibrating end of each of the piezoelectric plates is suppressed on the vibration suppression connection part side and a bending vibration at the upper vibrating end is amplified and then applied to the vibration shaft and the liquid detecting element which is disposed at a lower end of the vibration shaft, through the vibration connection part, so that the liquid detecting element is vibrated in the circular direction in the measuring liquid.

Abstract: A method for measuring viscosity and shear rate at which the measurement is performed is provided, by utilizing an acoustic wave sensor, and calculating the shear rate as a function of the characteristic rate of quartz movement in response to a given power transmitted to a fluid, and the viscosity of the fluid. Related aspects of the invention provide for methods for controlling the shear rate at which a viscosity measurement is performed, and characterizing viscoelastic fluids at a plurality of shear rates.

Abstract: Viscometer (80) with a sample cup (42) rotatable by a pulley (26) and a timing belt (30) to shear a tested fluid thus imparting torque to a bob (44) mounted on a shaft (10) supported via a frictionless bearing (58), an optical distance sensor assembly (12) measures the distance to an arm (70) which is connected to the top of shaft (10). This distance information is further converted to the viscosity of the tested fluid.

Abstract: A device for measuring the viscosity and/or the density of a fluid using a resonator capable of mechanical vibrations. The resonator is capable of being brought into contact with the fluid. An oscillator circuit is also provided, wherein the oscillator circuit has a first feedback network and a second feedback network.

Abstract: Described is a downhole apparatus for detecting and removing deposits from a surface exposed to wellbore fluids. The apparatus can monitor the rate of deposition and subsequently remove the deposited material. The combination of detection apparatus and removal apparatus provides a downhole instrument with self-cleaning operation mode.

Abstract: Described is an apparatus for detecting and removing deposits from a surface exposed to wellbore fluids. The apparatus can monitor the rate of deposition and subsequently remove the deposited material. The combination of detection apparatus and removal apparatus provides an instrument with self-cleaning operation mode.

Abstract: A method and apparatus for determining the vibration damping characteristics of an automotive brake structure measures the vibration response of a brake structure during application of random-frequency wide spectrum excitation, followed by measuring vibration of the structure at particularly noted modal frequencies, using a confined bandwidth random-frequency vibratory excitation. The method and apparatus may be used also to assess the bonding or attachment characteristics of damping materials.

Abstract: A method for sensing a chemical analyte in a fluid stream comprises providing a microfabricated teeter-totter resonator that relies upon a Lorentz force to cause oscillation in a paddle, applying a static magnetic field substantially aligned in-plane with the paddle, energizing a current conductor line on a surface of the paddle with an alternating electrical current to generate the Lorentz force, exposing the resonator to the analyte, and detecting the response of the oscillatory motion of the paddle to the chemical analyte. Preferably, a chemically sensitive coating is disposed on at least one surface of the paddle to enhance the sorption of the analyte by the paddle. The concentration of the analyte in a fluid stream can be determined by measuring the change in the resonant frequency or phase of the teeter-totter resonator as the chemical analyte is added to or removed from the paddle.

Abstract: A microfabricated teeter-totter resonator comprises a frame, a paddle pivotably anchored to the frame by pivot arms that define an axis of rotation, a current conductor line on a surface of the paddle, means for applying a static magnetic field substantially perpendicular to the rotational axis and in the plane of the paddle, and means for energizing the current conductor line with an alternating current. A Lorentz force is generated by the interaction of the magnetic field with the current flowing in the conductor line, causing the paddle to oscillate about the axis of rotation. The teeter-totter resonator can be fabricated with micromachining techniques with materials used in the integrated circuits manufacturing industry. The microfabricated teeter-totter resonator has many varied applications, both as an actuation device and as a sensor.

Abstract: A sensor for measuring the viscosity of a fluid, which has an oscillator. The oscillator is dipped into the fluid. The surface of the oscillator is provided with a dirt-repellent coating.

Abstract: A method and apparatus for measuring properties of a liquid composition includes a mechanical resonator, such as a cantilever, connected to a measurement circuit. The mechanical resonator can be covered with a coating to impart additional special detection propertied to the resonator, and multiple resonators can be attached together as a single sensor to obtain multiple frequency responses. The invention is particularly suitable for combinatorial chemistry applications, which require rapid analysis of chemical properties for screening.

Abstract: The invention relates to an apparatus for determining and/or monitoring the viscosity of a medium in a container, having a unit which can oscillate, having a drive/reception unit and having a control/evaluation unit, in which case the unit which can oscillate is arranged at a defined measurement position within the container and/or in which case a unit which can oscillate is fitted such that it is immersed as far as a defined immersion depth in the medium, and in which case the drive/reception unit excites the unit which can oscillate to oscillate and/or in which case the drive/reception unit receives the oscillations from the unit which can oscillate. The control/evaluation unit uses the frequency/phase curve (&phgr;=g(f)) of the unit which can oscillate to determine the viscosity (&eegr;) of the medium.

Abstract: A method and apparatus for analyzing a deposited layer on the inner surface of a fluid container wall having inner and outer surfaces are disclosed. One embodiment of the method comprises (a) transmitting an acoustic signal from a transmitter at a first distance from the outer surface of the wall; (b) receiving a first received signal A, comprising a reflection from the wall outer surface; (c) receiving a second received signal B, comprising a reflection from the wall inner surface; (d) receiving a third received signal C from the wall inner surface; (e) calculating a coefficient Rwp from A, B and C, and (f) calculating a coefficient Rpd from A, B and Rwp, and calculating the acoustic impedance of the deposited layer Zd from Rwp, Rpd, and Zw, where Zw is the acoustic impedance of the material between the transmitter and the wall outer surface.

Abstract: A method for measuring viscosity of liquid, in which a liquid detecting piece 3 is vibrated by a vibrator 1, vibration of the liquid detecting piece 3 in liquid 4 is detected, and viscosity of the liquid 4 is measured from vibration thus obtained, the method comprising the steps of detecting frequency and amplitude which are variable attributable to liquid-specific visco-elasticity from the vibration, obtaining impedance of the liquid from the frequency and the amplitude, and obtaining a dynamic viscosity from a real number part and an imaginary number part of the impedance. There is also disclosed a method for measuring visco-elasticity of liquid comprising the step of obtaining a dynamic viscosity, a dynamic elasticity and a static elasticity of the liquid from a real number part and an imaginary number part of the impedance.

Abstract: A brief but intense magnetic impulse generated by a coil 42 is used to excite resonant bending mode vibration in a magnetically permeable cantilevered beam 2 immersed in a fluid 22. A permanent magnet 36 and a magnetically permeable circuit 44, 38, 40, 56, 32, 6, and 2 enhance the magnetic coupling between the flexible beam 2 and the coil 42. A rigid post 6, positioned close to the beam and normal to the plane of oscillation is used to substantially increase the shearing induced in the fluid and thereby the rate of viscous attenuation of the vibrating beam. Oscillation of the vibrating beam 2 is detected by the same coil 42 that initiated the vibrations. The rate of decay of the vibrations is related to absolute viscosity.

Abstract: A brief but intense magnetic impulse generated by a coil 42 is used to excite resonant bending mode vibration in a magnetically permeable cantilevered beam 2 immersed in a fluid 22. A permanent magnet 36 and a magnetically permeable circuit 44, 38, 40, 56, 32, 6, and 2 enhance the magnetic coupling between the flexible beam 2 and the coil 42. A rigid post 6, positioned close to the beam and normal to the plane of oscillation is used to substantially increase the shearing induced in the fluid and thereby the rate of viscous attenuation of the vibrating beam. Oscillation of the vibrating beam 2 is detected by the same coil 42 that initiated the vibrations. The rate of decay of the vibrations is related to absolute viscosity.

Abstract: C9The invention relates to a method for determining the viscosity of an operating liquid of an internal combustion engine of a vehicle by establishing the level of the operating liquid. In a known method, the viscosity of the operating liquid is established from the changes to the level in the operating liquid over a period of time. This viscosity is determined after turning off the internal combustion engine by measuring the variation of the engine oil level over a period of time. The measurement can, however, also take place exclusively after the internal combustion engine has been turned off. In the present method, this disadvantage is avoided in that the level and the variation of the transverse acceleration are measured constantly in order to determine the viscosity of the operating liquid from the variation against time of the two signal curves.

Abstract: Workstation, apparatuses and methods for the high-throughput synthesis, screening and/or characterization of combinatorial libraries. The invention relates to an array, which permits various high-throughput methods for synthesis, screening and/or characterization in the same array, without requiring sample transfer from the array. In a preferred embodiment, the synthesis, screening, and/or characterization steps are carried out in a highly parallel fashion, where more than one compound is synthesized, screened, and/or characterized at the same time. The invention may be practiced at the microscale. The array may comprise thermal channels, for regulating the temperature of the wells in the array. The wells of the array may comprise a membrane, which is used in various screening and characterization methods. The invention also relates to a covered array, comprising the array and an array cover, as well as an apparatus comprising the array, which comprises the array, an array cover and a stage.

Abstract: The present invention relates to integrated micro-cantilevers, micro-bridges or micro-membranes in micro-liquid handling systems. Such micro-liquid handling systems provide novel detection mechanisms for monitoring the physical, chemical and biological properties of fluids in such systems. The present invention further relates to micro-cantilever, micro-bridge or micro-membrane type sensors having integrated readout. Such constructions allow laminated flows of different liquids to flow in a channel without mixing, which opens up for new type of experiments and which reduces noise related to the liquid movement. The present invention even further relates to sensors having adjacent or very closely spaced micro-cantilevers, micro-bridges or micro-membranes which can be exposed to different chemical environments at the same time.

Abstract: The viscometer provides a viscosity value (X&eegr;) which represents the viscosity of a fluid flowing in a pipe connected thereto. It comprises a vibratory transducer with at least one flow tube (13) for conducting the fluid, which communicates with the pipe. Driven by an excitation assembly (16), the flow tube (13) is vibrated so that friction forces are produced in the fluid. The viscometer further includes meter electronics (50) which feed an excitation current (iexc) into the excitation assembly (16). By means of the meter electronics (50), a first internal intermediate value (X1) is formed, which corresponds with the excitation current (iexc) and thus represents the friction forces acting in the fluid. According to the invention, a second internal intermediate value (X2), representing inhomogeneities in the fluid, is generated in the meter electronics (50), which then determine the viscosity value (X&eegr;) using the two intermediate values (X1, X2).

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: A method and apparatus for analyzing a deposited layer on the inner surface of a fluid container wall having inner and outer surfaces are disclosed. One embodiment of the method comprises (a) transmitting an acoustic signal from a transmitter at a first distance from the outer surface of the wall; (b) receiving a first received signal A, comprising a reflection from the wall outer surface; (c) receiving a second received signal B, comprising a reflection from the wall inner surface; (d) receiving a third received signal C from the wall inner surface; (e) calculating a coefficient Rwp from A, B and C, and (f) calculating a coefficient Rpd from A, B and Rwp, and calculating the acoustic impedance of the deposited layer Zd from Rwp, Rpd, and Zw, where Zw is the acoustic impedance of the material between the transmitter and the wall outer surface.

Abstract: A transducer includes a resonant structure having a first spring-mass system extending to a connection mass or nexus to which is connected a second spring-mass system, which includes a sensing element. The two spring-mass systems vibrate in antiphase. The nexus is connected to a mechanical datum provided by a mounting by means of a semi-rigid connection member which is preferably stiffer than the first member and which can control the relative motions of the first and second spring-mass systems. The sensing element contains a re-entrant resonator constituted by a spring-mass system, which can be used to adjust the characteristics of the transducer.

Abstract: To measure characteristics of a non-Newtonian fluid, preferably blood, a non-magnetic container is provided for receiving the fluid. A magnetic body is contained in the container, and a winding is provided around the container. An AC current supplying device is connected to the winding for supplying input AC current of different amplitudes thereto to generate magnetic fields of different strengths in the container to cause the magnetic body to oscillate at different shear rates in the fluid. A measuring device is provided for measuring amplitude and/or phase of the oscillations of the magnetic body and a shear rate determining device is provided for determining the shear rates by measuring differences between the amplitude and/or phase of the oscillations of the magnetic body and the amplitude and phase of the input AC currents.

Abstract: The invention relates to an apparatus for determining and/or monitoring the viscosity of a medium in a container, having a unit which can oscillate (2), having a drive/reception unit (4, 5, 6) and having a control/evaluation unit (8), in which case the unit which can oscillate (2) is arranged at a defined measurement position within the container and/or in which case a unit which can oscillate (2) is fitted such that it is immersed as far as a defined immersion depth in the medium, and in which case the drive/reception unit (4, 5) excites the unit which can oscillate (2) to oscillate and/or in which case the drive/reception unit (4, 6) receives the oscillations from the unit which can oscillate (2).

Abstract: To detect rheological material properties of a fluid, flowable or elastic material, the material is exposed to harmonic excitation with at least one fundamental and at least one parameter F is measured that is variable in response to the harmonic excitation and suitable for determining a new material parameter, whereby measurement of the parameter F comprises recording of a time function F(t) of the parameter and the time function F(t) is subjected to Fourier transformation to form a shear spectrum in which the rheological material properties can be detected from the position of the frequency components, their intensity and/or their dependence on the fundamental.

Abstract: A method for measuring viscosity of liquid, in which a liquid detecting piece 3 is vibrated by a vibrator 1, vibration of the liquid detecting piece 3 in liquid 4 is detected, and viscosity of the liquid 4 is measured from vibration thus obtained, the method comprising the steps of detecting frequency and amplitude which are variable attributable to liquid-specific visco-elasticity from the vibration, obtaining impedance of the liquid from the frequency and the amplitude, and obtaining a dynamic viscosity from a real number part and an imaginary number part of the impedance. There is also disclosed a method for measuring visco-elasticity of liquid comprising the step of obtaining a dynamic viscosity, a dynamic elasticity and a static elasticity of the liquid from a real number part and an imaginary number part of the impedance.

Abstract: This invention relates to a method for deciding an amount of correction factor for the viscosity of a fluid test sample needed for correcting a calculation or measurement of the density based on the viscosity. The method for deciding the viscosity of the fluid test sample, during a density measurement performed by an oscillating densitometer where there is a peak point on the viscosity-attenuation constant characteristic of the test sample at the specific order oscillation, is to decide whether the attenuation constant of the viscosity-attenuation constant characteristic of the test sample at the other specific order oscillation is larger or smaller than that corresponding to the peak point, to decide according to said decision whether the viscosity detected by the attenuation constant obtained at the specific order oscillation belongs to either side larger or smaller than the peak point, and then to decide upon and determine the viscosity of the test sample according to the above two decisions.

Abstract: A piezoelectric sensor device has a piezoelectric body vibrator consisting of the piezoelectric body which is sandwiched by a pair of electrodes, a power source which applies a voltage to the piezoelectric body vibrator so as to get excited for vibration, means for monitoring electric constants to detect changes in electric constants accompanied by vibration of the piezoelectric body. The change in electric constants in the piezoelectric body is detected as a change in frequency for vibration of the piezoelectric body corresponding to an electric constant under the determined conditions. The piezoelectric sensor device has a means to obtain the frequency value from frequencies at not less than two points giving a determined electric constant. According to the piezoelectric sensor device the dispersion in measured values due to change in vibration aptness of vibration system and the polarization state of piezoelectric body vibrator can be made smaller.

Abstract: A method and apparatus for measuring the viscosity and/or specific density of a fluid utilizes a microcantilever vibrated in the analyte fluid. The source of vibration is switched on and off and the transient behavior or decay in amplitude of the vibration is monitored. The method is particularly useful for the measurement of process conditions in remote locations in real time.

Abstract: A suspension of a starch-containing product in heated during agitation, whereby the viscosity is registered as a function of the temperature. A curve over the relationship between viscosity an temperature is treated as a property profile for the sample and is compared with another known curve in order to determine the heating properties for the sample. A device for this analysis has an agitator (7), the drive means (10, 11) of which has a power sensor (12) for sensing the power which the agitator is subjected to during the agitating, whereby a measure of the viscosity is obtained. A temperature sensor (13) senses the temperature of the sample.