Abstract: An improved invasive acoustic sensor apparatus detects particulate matter in a flow by impingement thereon. The apparatus includes an axially extending probe body having an active length positionable in a flow and a distributed piezoelectric transducer disposed therein. The transducer is acoustically coupled to an interior surface of the body, along substantially the entire active length thereof, and may be a piezoelectric film, piezoelectric tube, or a plurality of electrically parallel connected piezoelectric tube elements. The apparatus further includes an acoustic isolation layer disposed between the probe body and positioning structure to reduce transmission of process wall vibration to the transducer.

Abstract: An on-line nuclear magnetic resonance (NMR) system, and related methods, are useful for predicting one or more properties of interest of a polymer. In one embodiment, a neural network is used to develop a model which correlates process variables in addition to manipulated NMR output to predict a polymer property of interest. In another embodiment, a partial least square regression technique is used to develop a model of enhanced accuracy. Either the neural network technique or the partial least square regression technique may be used in conjunction with a described multi-model or best-model-selection scheme according to the invention. The polymer can be a plastic such as polyethylene, polypropylene, or polystyrene, or a rubber such as ethylene propylene rubber.

Abstract: A real-time, on-line nuclear magnetic resonance (NMR) system, and related method, can predict various properties of interest of a sample of polymer material. A regression or neural network technique is used to develop a model based upon manipulated NMR output and a resin age factor which compensates for time dependent aging phenomena and enhance predictive accuracy of the model. In a preferred embodiment, the resin age factor is a function of elapsed cycle time prior to sample measurement, sample temperature at time of measurement, and/or sample form. The polymer can be a plastic such as polyethylene, polypropylene, or polystyrene, or a rubber such as ethylene propylene rubber.

Abstract: Pulsed NMR system for industrial measurements comprising sample throughput system (P, LI, V1, V2) and user system controls (104) to establish digitized free induction decay (FID) curves (C), from which fast Gaussian, slower modified Gaussian or preferably slower Gaussian, and exponential components are determined using a Marquardt-Levenberg iteration technique, and using regression techniques to correlate the FID curve components to the physical quantities of the target nuclei.

Abstract: Pulsed NMR system for industrial measurements comprising sample throughput system (P, LI, V1, V2) and user system controls (104) to establish digitized free induction decay curves (C), from which Abragam, Gaussian, and exponential components are determined using a Marquardt-Levenberg iteration technique, and using regression techniques to correlate the curve components to the target nuclei.

Abstract: A nuclear magnetic resonance (NMR) system, and related method, develops two or more regression equations or models for a particular polymer property of interest (e.g., melt index or MI) during a calibration procedure using known samples of a material. The polymer material can be, for example, a plastic (e.g., polyethylene, polypropylene, or polystyrene) or a rubber (e.g., ethylene propylene rubber). Regression models for one or more discrete (i.e., two-valued) variables also are developed during calibration, and these models allow a prediction to be made about which of the two or more property (e.g., MI) models should be used for any particular sample of unknown material. The prediction obtained from the discrete variable model indicates which of the two or more models will produce the most accurate estimation of the property of interest for the unknown sample. The best model is thus selected, and then it is used to estimate the property of interest.

Abstract: A microprocessor (48) controlled triboelectric instrument with probe fouling detection, zero offset adjustments and temperature compensation. The system programmability provides for enhanced operator control and operator monitoring wherein the system may be reprogrammed to advantage to reduce instrument down time.

Abstract: A multi-wavelength spectrofluorometer suitable for operation in laboratory, process control environments and in the field. The unit includes a multi-source flash tube, slits, diffraction grating arrangement(s) and other optics whereby a number of different wavelengths are available for exciting the sample. Also, a slit moving along the tubular axis of a single flash tube may be used. The excitation light is directed onto a sample and the luminescent emitted light from the sample is measured for intensity and wavelength. The resulting "signature" is compared with stored "signatures" for identification purposes. A controller with storage, keyboard and display provides interactive operation for the user. Separate memory cards with stored known component signatures and other analysis programs may be inserted into the instrument. Modules for directing the analysis to remote samples and to solid, liquid or gas samples are provided.

Abstract: A pulsed NMR analysis system and process comprising an on-line system to extract a sample and establish digitized free induction decay curves (C), from which curve components functions are determined using regression techniques to correlate the curve components to the target nuclei, crystalline or amorphous, and to other material characteristics, such as flow rates in plastic (MI and FRR for polyethylene and MF for polypropylene). The invention makes use of Principal Component Analysis (PCA) for deriving an orthogonal set of explanatory parameters and therefrom a set of vectors wherein collinearity is eliminated by Eigenvalue analysis.

Abstract: A pulsed nmr analysis system for polymers materials extracted from industrial processes at a mobility enhancing temperature (at or above glass transition temperature for amorphous polymers, at the crystalline transition temperature for crystalline and semi-crystalline polymers). The sample is measured via nmr techniques and results correlated to viscosity and melt index or melt flow (which are related to average molecular weights). The nmr system (in or out of resonance) includes: sample throughput system (P, LI, V1, V2) and user system controls (104) to establish digitized free induction decay curves (C), from which components functions are determined using linear or non-linear regression techniques to correlate the curve components to the target nuclei and to flow rates in plastics.

Abstract: Apparatus and process for measuring mass flow of a slurry mixture of two components of materials, such as a flow of catalyst solid particles (the first component) or droplets in a fluid carrier (the second component). The slurry mixture is added to a process stream (10) or batch reactor. The flow velocity and the volume fraction of one component are measured and combined with the known specific gravity, of the component being measured, and the physical dimensions of the pipe, in which the slurry mixture is flowing, to determine the mass flow of the component. The flow velocity is measured by correlating signals at two separated locations along the flow path, and the volume fraction is measured by combining the known dielectric constants of each of the materials in the mixture and the measured capacitance of the mixture. The capacitance is measured from electrodes which may be isolated from the flowing materials in some applications, but not isolated from the flowing materials in other applications.

Abstract: A pulsed NMR analysis system and process comprising an air curtain (137), sample throughput system (P, LI, V1, V2) and user system controls (104) to establish digitized free induction decay curves (C) , from which components functions are determined using linear or nonlinear regression techniques to correlate the curve components to the target nuclei and to flow rates in plastic including MI and FRR for polyethylene and MF for polypropylene.

Abstract: A miniature surgical instrument (10) comprises a handle (12), shaft assembly (26) with an actuating linkage (L1, L2) movable freely therein and a distal working tip (30) with a shaft rotation sub-assembly (22, 24, 34) including multiple spring-stop pairs (40, 38) arranged in an annulus (44) around the shaft to receive cleansing water via an injection port (52) and/or through the handle and to pass it to the interior of the shaft via a port (12C) or past a seal (56) for flow of water in the shaft around the linkage and exiting in the tip vicinity to clear away surgical debris, the arranging allowing independent operation of the linkage, a lock (14) for the linkage and the tip rotation means. The arrangement prevents or minimizes debris accumulation in the first instance through its avoidance of a pressure differential from an insufflated body cavity to ambient air via the instrument.

Abstract: A pulsed NMR analysis system and process comprising sample throughput system (P, LI, V1, V2) and user system controls (104) to establish digitized free induction decay curves (C), from which components functions are determined using non-linear regression techniques to correlate the curve components to the target nuclei.

Abstract: Pulsed NMR system for industrial measurements comprising sample throughout system (P, LI, V1, V2) and user system controls (104) to establish digitized free induction decay curves (C), from which Abragam, Gaussianand exponential components are determined using a Marquardt-Levenberg iteration technique, and using regression techniques to correlate the curve components to the target nuclei.

Abstract: Pulsed NMR system for industrial measurements comprising sample throughput system (P, LI, V1, V2) and user system controls (104) to establish digitized free induction decay (FID) curves (C), from which fast Gaussian, slower modified Gaussian and exponential components are determined using a Marquardt-Levenberg iteration technique, and using regression techniques to correlate the FID curve components to the physical quantities of the target nuclei.

Abstract: An improved input circuit (9) for accepting a signal from a triboelectric probe (2). The circuitry provides gain, zero and probe contamination information which allows verification of said information without taking the probe and instrument off-line.

Abstract: A sample holder and compactor system (10), for use in an industrial NMR (or like) instrument, wherein particulate non-uniform samples can be loaded and compacted. The system comprises a tubular holder/compactor member (20) with an internal sleeve (26) and a ram (30), all fabricated from materials that are non-interactive with the excitation NMR fields and do not interfere with the sample analysis and provides a repeatable, simple way of handling disparate materials in routine repeatable ways ensuring reliable NMR analyses.

Abstract: Monitoring apparatus (10) of particles in a gas stream comprising a probe (12) and circuit (14) for detecting electrical activity of the probe and an actuator (20) for insertion and retraction of the probe into and out of the stream, the circuit providing periodic measurement of the retracted probe and self-adjustment to compensate for changing probe characteristics. The apparatus also provided probe cleaning and protection means (30, 32, 34, 36), which work in interaction with the self-check instrumentation. The self-check tests include baseline, gain and sensitivity monitoring.

Abstract: Particle analysis apparatus (10) in combination with a triboelectric probe (P) and including means (18, 20, 22, 24, 26) to analyze individual particle collisions with the probe as a useful measure of flow conditions--of a fluid with suspended solid particles--in the region of the probe.