A NEMS readout system includes a sensor array comprising a plurality of sensors. Each sensor of the plurality of sensors including a resonator with frequency characteristics different from the resonator of each other sensor of the plurality of sensors. A readout signal indicative of a plurality of output signals is collected from the sensor array. Each output signal of the plurality of output signals corresponding to one of the plurality of sensors. An analysis of the plurality of output signals is performed to identify a plurality of resonant frequencies and to detect a frequency shift associated with at least one of the plurality of resonant frequencies.

Methods are provided for characterizing the stability of a distillate fraction using a quartz crystal microbalance apparatus, such as a distillate fraction derived at least in part from a pre-refined crude oil. A sample can be aged for an aging period in a quartz crystal microbalance apparatus, and a frequency value for the sample in the quartz crystal microbalance apparatus can be determined before and after the aging period to determine a frequency difference. This frequency difference can be correlated directly with the ability of a jet fuel fraction to satisfy a stability test standard, such as a jet fuel breakpoint stability. The methods can also include using a temperature profile during characterization that can reduce or minimize operator error during the characterization.

A system and method for the acoustic detection of cracks in a semiconductor substrate is disclosed. In one example, the system includes a force generating unit configured to apply a force onto the semiconductor substrate, a detector unit comprising a resonating indenter and an acoustic emission sensor coupled to the resonating indenter, and an evaluation unit configured to evaluate acoustic signals detected by the detector unit and configured to determine whether a crack has occurred based on the detected signals. The resonating indenter is configured to contact the semiconductor substrate at a lateral distance from the force generating unit, and wherein the force generating unit and the resonating indenter are configured to contact the semiconductor substrate on the same side.

An apparatus for determining and/or monitoring at least one process variable of a medium in a container, comprising at least an oscillatable unit having at least one membrane, and at least one oscillatory element, a driving/receiving unit embodied to excite the mechanically oscillatable unit by means of an electrical, exciter signal of adjustable excitation frequency to execute oscillations in an oscillation mode corresponding to the excitation frequency and to receive mechanical oscillations from the oscillatable unit and to convert such into an electrical received signal, and an electronics unit embodied, to produce the exciter signal, and to ascertain from the received signal the at least one process variable. The membrane is connected with the driving/receiving unit. The oscillatory element has the shape of an oscillatory rod, on which a paddle is terminally formed, and the oscillatory element is secured on the membrane in an end region remote from the paddle. Mass distribution, stiffness and/or geometry of the oscillatable unit is/are selected in such a manner that at least one of the oscillation modes of the oscillatable unit higher in reference to the oscillation mode corresponding to the excitation frequency lies in the range between two neighboring whole-numbered multiples of the excitation frequency.

Disclosed are methods for determining and classifying aircraft air contaminants comprising one or more of: turbine engine oil, hydraulic fluid and deicing fluid using contaminant analyzers comprising a contaminant collector comprising a membrane and a heater vaporizing the contaminants; a gravimetric sensor generating a response when contaminant mass is added to or removed from the sensor, the sensor receiving contaminants desorbed from the heated membrane; a frequency measurement device, measuring the response generated by the sensor as the contaminant is added to and removed from the sensor; a computer readable medium bearing a contaminant recognition program and calibration data; a processor executing the program, the program including a module classifying contaminants by type, and a module using the data for comparison with magnitude of response generated by the sensor to calculate contaminant concentration; and, a pump, generating flow of air through the collector before and after the membrane is heated.

In an embodiment, a system includes a plurality of sensor devices contained in a plurality of wells contained in a well-plate assembly. The sensor devices are used in a plurality of oscillators. Each oscillator generates a frequency and a resistance based on a quality of living biological cells contained in a corresponding well. The quality may include, for example, surface coupled mass, density, viscosity, and/or viscoelasticity of the living biological cells. The system also includes logic for measuring a resonant frequency and motional resistance associated with each sensor device and logic for processing the measured resonant frequency and motional resistance. Moreover, the system includes logic for displaying one or more graphs showing one or more characteristics of the living biological cells contained in the wells.

To detect air in a fluid delivery line of an infusion system, infusion fluid is pumped through a fluid delivery line adjacent to at least one sensor. A signal is transmitted and received using the at least one sensor into and from the fluid delivery line. The at least one sensor is operated, using at least one processor, at a modified frequency which is different than a resonant frequency of the at least one sensor to reduce an amplitude of an output of the signal transmitted from the at least one sensor to a level which is lower than a saturation level of the analog-to-digital converter to avoid over-saturating the analog-to-digital converter. The signal received by the at least one sensor is converted from analog to digital using an analog-to-digital converter. The at least one processor determines whether air is in the fluid delivery line based on the converted digital signal.

The invention provides a chemical detection system for detecting at least one target chemical species, including a self-sensed cantilevered probe array having a plurality of self-sensed cantilevered probes, at least one chemical-sensitive coating material applied to at least one cantilevered probe in the cantilevered probe array, and an interface circuit that is coupled to the cantilevered probe array. At least one cantilevered probe in the cantilevered probe array exhibits a shifted cantilevered probe response when the cantilevered probe array is exposed to the target chemical species and the interface circuit actuates the cantilevered probe. A handheld chemical detection system and a method of operation are also disclosed.

A device for estimating a mechanical property of a sample is disclosed herein. The device may include a chamber configured to hold the sample; a transmitter configured to transmit a plurality of waveforms, including at least one forcing waveform; and a transducer assembly operatively connected to the transmitter and configured to transform the transmit waveforms into ultrasound waveforms. The transducer assembly can also transmit and receive ultrasound waveforms into and out of the chamber, as well as transform at least two received ultrasound waveforms into received electrical waveforms. The device also includes a data processor that can receive the received electrical waveforms; estimate a difference in the received electrical waveforms that results at least partially from movement of the sample; and estimate a mechanical property of the sample by comparing at least one feature of the estimated difference to at least one predicted feature, wherein the at least one predicted feature is based on a model of an effect of the chamber wall. Finally, the device can also include a controller configured to control the timing of the ultrasound transmitter and data processor.

Apparatus for chemical detection includes a pair of interdigitated transducers (IDTs) formed on a piezoelectric substrate. The apparatus includes a layer of adsorptive material deposited on a surface of the piezoelectric substrate between the IDTs, where each IDT is conformed, and is dimensioned in relation to an operating frequency and an acoustic velocity of the piezoelectric substrate, so as to function as a single-phase uni-directional transducer (SPUDT) at the operating frequency. Additionally, the apparatus includes the pair of IDTs is spaced apart along a propagation axis and mutually aligned relative to said propagation axis so as to define an acoustic cavity that is resonant to surface acoustic waves (SAWs) at the operating frequency, where a distance between each IDT of the pair of IDTs ranges from 100 wavelength of the operating frequency to 400 wavelength of the operating frequency.