3492results about "Material analysis by using resonance" patented technology

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.

An apparatus for detecting chemical substances which is high in sensitivity and selectivity is provided.

An organic acid or an organic acid salt is used to generate an organic acid gas from an organic acid gas generator 3 to be mixed with a sample gas for introduction into an ion source 4 for ionization, thereby obtaining a mass spectrum by a mass analysis region 5. A data processor 6 determines the detection or non-detection of a specific m/z of an organic acid adduct ion obtained by adding a molecule generated from the organic acid to a molecule with specific m/z generated from a target chemical substance to be detected based on the obtained mass spectrum. When there is an ion peak with the m/z of the organic acid adduct ion, the presence of the target chemical substance to be detected is determined, and an alarm is sounded. False detection can be prevented.

PCT No. PCT/GB96/01830 Sec. 371 Date Apr. 21, 1998 Sec. 102(e) Date Apr. 21, 1998 PCT Filed Jul. 25, 1996 PCT Pub. No. WO97/05280 PCT Pub. Date Feb. 13, 1997The invention relates to the detection of target nucleic acids or nucleic acid units in a sample, by obtaining a SER(R)S spectrum for a SER(R)S-active complex containing, or derived directly from, the target. The complex includes at least a SER(R)S-active label, and optionally a target binding species containing a nucleic acid or nucleic acid unit. In this detection method, the concentration of the target present in the SER(R)S-active complex, or of the nucleic acid or unit contained in the target binding species in the SER(R)S-active complex, is no higher than 10-10 moles per liter. Additionally or alternatively, one or more of the following features may be used with the method: i) the introduction of a polyamine; ii) modification of the target, and/or of the nucleic acid or nucleic acid unit contained in the target binding species, in a manner that promotes or facilitates its chemi-sorption onto a SER(R)S-active surface; iii) inclusion of a chemi-sorptive functional group in the SER(R)S-active label. The invention also provides SER(R)S-active complexes for use in such a method, a kit for use in carrying out the method or preparing the complexes and a method for sequencing a nucleic acid which comprises the use of the detection method to detect at least one target nucleotide or sequence of nucleotides within the acid.

Ultrasonic waveguides having improved velocity gain are disclosed for use in ultrasonic medical devices. Specifically, the ultrasonic waveguides comprises a first material having a higher acoustic impedance and a second material having a lower acoustic impedance.

A method for determining the quality of an examined weld joint comprising the steps of providing acoustical data from the examined weld joint, and performing a neural network operation on the acoustical data determine the quality of the examined weld joint produced by a friction weld process. The neural network may be trained by the steps of providing acoustical data and observable data from at least one test weld joint, and training the neural network based on the acoustical data and observable data to form a trained neural network so that the trained neural network is capable of determining the quality of a examined weld joint based on acoustical data from the examined weld joint. In addition, an apparatus having a housing, acoustical sensors mounted therein, and means for mounting the housing on a friction weld device so that the acoustical sensors do not contact the weld joint. The apparatus may sample the acoustical data necessary for the neural network to determine the quality of a weld joint.

Mass spectrometry of large nucleic acids by infrared Matrix-Assisted Laser Desorption/Ionization (MALDI) using a liquid matrix is reported.

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.

Processes are disclosed using the depolymerization of a nucleic acid hybrid and incorporation of a suitable nucleotide to qualitatively and quantitatively analyze for the presence of predetermined nucleic acid target sequences. Applications of those processes include the detection of single nucleotide polymorphisms, identification of single base changes, genotyping, medical marker diagnostics, mirosequencing, and.

This invention relates generally to a mass spectrometer probe and a method of using said probe for desorption and ionization of analytes. The sample probe comprises an affinity reagent on the probe surface, wherein the affinity reagent is capable of selectively binding an analyte. An analyte bound to the affinity reagent can be desorbed by a high energy source and detected in the mass spectrometer. The probe and methods are useful in detection and analysis of macromolecules such as proteins or other biomolecules.

Method and implementing apparatus useful in acquiring data on acoustic features within a sample provides a pulsed acoustic probe and a stage system for effecting relative movement between the sample and the probe. The stage system is commanded such that the probe interrogates a non-rectangularly bounded space on the sample surface or within the volume of the sample. Acoustic energy reflected from or transmitted through the sample is sensed. Amplitude signals are developed from the sensed acoustic energy. Data characterizing the developed amplitude signals are stored for subsequent processing.

An ultrasonic probe includes a light irradiating portion configured to radiate light for generating ultrasonic waves from a light absorber, an ultrasonic transducing portion configured to transduce the ultrasonic waves to an electric signal, and a light guide member configured to introduce light from a light source to the light irradiating portion. A light irradiating region of the light irradiating portion is included within an ultrasonic receiving region of the ultrasonic transducing portion.

The instant invention involves the use of a combination of preparatory steps in conjunction with mass spectroscopy and time-of-flight detection procedures to maximize the diversity of biopolymers which are verifiable within a particular sample. The cohort of biopolymers verified within such a sample is then viewed with reference to their ability to evidence at least particular disease state; thereby enabling a diagnostician to gain the ability to characterize either the presence or absence of at least one disease state relative to recognition of the presence and/or the absence of the biopolymer.

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.