Abstract: A method for measuring concentration of an analyte in body fluid comprises acquiring a body fluid sample, emitting light into the body fluid sample, and detecting emitted light intensity on a plurality of optical paths through the body fluid sample. A plurality of optical filters are arranged in respective optical paths of the optical path plurality comprising at least a first optical filter with light absorption by an analyte and water and a second optical filter with light absorption to water alone. Light intensity passed through the first optical filter and passed through the second optical filter is measured and analyte concentration is determined based on a ratio of intensities detected at a detector in an optical path intersected by the first optical filter and detected at a detector in an optical path intersected by the second optical filter.

Abstract: In a tissue sensor, a plurality of emitters are configured to emit narrowband light into biological tissue at a plurality of selected wavelengths including one or more wavelengths indicative of a profile for one or more selected analytes and a reference wavelength at which absorbance for the selected analyte is negligible. The sensor further comprises a photo detector configured to detect light at wavelengths that emerge from the biological tissue.

Abstract: Glucose concentration is noninvasively measured by measuring a plurality of absorption values using at least one emitter operating at a corresponding plurality of emission wavelengths through a common optical sample volume and deriving glucose concentration from the absorption measurement values.

Abstract: Multiple components are selected, conveyed, and measured in a polymerization system. A control system adjusts the system variables to the desired values. Portions of the components can be fed to a pre-contactor before introduction into the polymerization reactor. The catalyst component concentrations and residence times are tightly controlled in the pre-contactor to affect product properties. The pre-contactor can be a single or multiple combinations of a CSTR or plug flow pre-contactors.

Abstract: A catalyst activator vessel for heat conditioning a catalyst is disclosed. The activator vessel includes inner and outer vessels, a perforated, normally generally horizontal grid plate within the inner vessel, and a fluid path extending through the grid plate within the vessel. The inner vessel can have an inside diameter of at least 50 inches (1.27 m). The space between the inner and outer vessels defines a flue. The perforated grid plate within the inner vessel can have an upper surface perforated with a pattern of overlapping, generally conical depressions and a lower surface, optionally overlapping by at least 17%. The fluid path extends upwardly through the perforated grid plate and is a conduit along which a fluid flows through the grid plate. The fluid will fluidize a particulate material, such as a catalyst, disposed above the grid plate in the inner vessel.

Abstract: An olefin polymerization process and apparatus wherein a fluid slurry comprising monomer, diluent and catalyst is circulated in a continuous loop reactor by two or more pumps. The process and apparatus allow operating the reaction at significantly higher solids content in the circulating fluid slurry. In a preferred embodiment, the fluid slurry is circulated by two impellers arranged so that the downstream impeller benefits from the rotational energy imparted by the upstream impeller. An olefin polymerization process operating at higher reactor solids by virtue of more aggressive circulation has improved efficiencies, particularly in larger-volume reactors.

Abstract: A slurry polymerization process removes a portion of the fluid slurry without using a settling leg or a continuous take-off. The process uses a reactor take-off valve that is periodically fully closed and fully opened such that the withdrawn slurry is removed from the reactor in a discontinuous manner. The regular, periodic full closing and full opening of the take-off valve reduces instances of polymer plugging the take-off valve. In another aspect of the invention, a take-off valve is throttled in a repetitive pattern to reduce plugging of the take-off valve.

Abstract: An olefin polymerization process and apparatus wherein a fluid slurry comprising monomer, diluent and catalyst is circulated in a continuous loop reactor by two or more pumps. The process and apparatus allow operating the reaction at significantly higher solids content in the circulating fluid slurry. In a preferred embodiment, the fluid slurry is circulated by two impellers arranged so that the downstream impeller benefits from the rotational energy imparted by the upstream impeller. An olefin polymerization process operating at higher reactor solids by virtue of more aggressive circulation has improved efficiencies, particularly in larger-volume reactors.

Abstract: Techniques are provided for the prevention of reactor fouls in polymerization reactors. A technique is provided for limiting polymer particle size to prevent or limit the occurrence of reactor fouls associated with large polymer particles. A technique is also provided for measuring reactor temperature at one or more local hot spots of the reactor and for controlling the polymerization reaction based upon these temperature measurements. In particular, control of the reaction may be based on the hottest temperature, such that the hottest temperature in the reactor is maintained within the reactor fouling curve. A technique is also discussed for predicting reactor fouls by using statistical analyses, such as periodogram analysis, to identify leading indicators of impending fouls. Preventative measures may be performed upon identification of such a leading indicator. In addition, the statistical analyses may be used to identify catalysts having less propensity to foul.

Abstract: A latching mechanism useful in the raising and lowering of luminaires mounted to a support ring and positionable at an upper end of a high mast, the invention comprehends a latch pin capable of articulating attachment to the support ring for preventing damage to latching structure and for reducing the potential for jamming as the latch pin engages latch cams on raising of the support ring. The latch pin is particularly configured with a ball-shaped swivel joint capable of reducing the potential for damage to the pin and associated structure by permitting the support ring to tilt if canted during a lowering operation. The latch pin is further configured with a nose portion of a diameter sufficient to center the latch pin relative to latch cams on raising of the support ring, thereby to reduce the potential for jamming.

Abstract: An optical sensor includes an optical source capable of being positioned on a tissue and emitting near infrared light into the tissue at a plurality of selected wavelengths, and a photodetector capable of detecting reflected light from the tissue. The photodetector being positioned on the tissue removed from the optical source but sufficiently close in proximity to the optical source to contact the same general tissue. The optical sensor further includes an oscillator coupled to the optical source and capable of activating the optical source to emit the near infrared light, and a modulator coupled to the oscillator and capable of controlling radio frequency modulation of the optical source to emit a radio frequency component that is used to measure the optical path length and absorbance of an analyte of interest within the tissue.

Abstract: A slurry polymerization process removes a portion of the fluid slurry without using a settling leg or a continuous take-off. The process uses a reactor take-off valve that is periodically fully closed and fully opened such that the withdrawn slurry is removed from the reactor in a discontinuous manner. The regular, periodic full closing and full opening of the take-off valve reduces instances of polymer plugging the take-off valve. In another aspect of the invention, a take-off valve is throttled in a repetitive pattern to reduce plugging of the take-off valve.

Abstract: An olefin polymerization process and apparatus wherein a fluid slurry comprising monomer, diluent and catalyst is circulated in a continuous loop reactor by two or more pumps. The process and apparatus allow operating the reaction at significantly higher solids content in the circulating fluid slurry. In a preferred embodiment, the fluid slurry is circulated by two impellers arranged so that the downstream impeller benefits from the rotational energy imparted by the upstream impeller. An olefin polymerization process operating at higher reactor solids by virtue of more aggressive circulation has improved efficiencies, particularly in larger-volume reactors.

Abstract: A slurry polymerization process wherein olefin monomer is fed to a continuous loop reactor at two or more points, allowing operation at higher and steadier monomer concentrations in the circulating slurry. A loop reactor apparatus has two or more monomer feeds and may have two or more catalyst feeds and/or two or more product take-offs, and each feed may have its own associated control scheme.

Abstract: A catalyst activator vessel for heat conditioning a catalyst is disclosed. The activator vessel includes inner and outer vessels, a perforated, normally generally horizontal grid plate within the inner vessel, and a fluid path extending through the grid plate within the vessel. The inner vessel can have an inside diameter of at least 50 inches (1.27 m). The space between the inner and outer vessels defines a flue. The perforated grid plate within the inner vessel can have an upper surface perforated with a pattern of overlapping, generally conical depressions and a lower surface, optionally overlapping by at least 17%. The fluid path extends upwardly through the perforated grid plate and is a conduit along which a fluid flows through the grid plate. The fluid will fluidize a particulate material, such as a catalyst, disposed above the grid plate in the inner vessel.

Abstract: A diagnostic apparatus includes a near infrared spectrophotometer (NIRS) and an ultrasound transducer that operate in combination to improve diagnostic measurements. The diagnostic apparatus includes a near infrared spectrophotometer that measures an analyte, for example tissue oxygenation, in an optical sample volume and an ultrasound imager to accurately position the optical sample volume in biological tissue or vessels. In one example, the diagnostic apparatus includes an optical source, a linear array of ultrasound transducers, and an optical photodetector arranged in the same plane so that the ultrasound sample volume interrogated by the ultrasound transducers intersects the optical sample volume formed by the optical source and detector.

Abstract: The invention relates to blow molding of an article having an inwardly projecting hollow boss with a closed end. A portion of a molten parison conforms to the shape of a fixed pin projecting from the face of a mold part to thereby form the hollow boss. The invention includes an apparatus comprising a reciprocable sleeve slidably received within the mold part over the pin. It has been found that by blow molding the parison with the sleeve initially extended with its end substantially flush with the end of the pin, followed by retracting the sleeve to a retracted position after a predetermined delay time, a boss with a thicker end results. Consequently, the boss end has greater structural integrity, and thus minimizes or eliminates the possibility of penetration and/or cracking of the boss end when a screw is threadedly received in the hollow boss.

Abstract: The invention relates to blow molding of an article having an inwardly projecting hollow boss with a closed end. A portion of a molten parison conforms to the shape of a fixed pin projecting from the face of a mold part to thereby form the hollow boss. An apparatus disclosed herein includes a reciprocable sleeve slidably received within the mold part over the pin. It has been found that by blow molding the parison with the sleeve initially extended with its end substantially flush with the end of the pin, followed by retracting the sleeve to a retracted position after a predetermined delay time, a boss with a thicker end results. Consequently, the boss end has greater structural integrity, and thus minimizes or eliminates the possibility of penetration and/or cracking of the boss end when a screw is threadedly received in the hollow boss.

Abstract: The invention relates to blow molding of an article having an inwardly projecting hollow boss with a closed end. A portion of a molten parison conforms to the shape of a fixed pin projecting from the face of a mold part to thereby form the hollow boss. The invention includes an apparatus comprising a reciprocable sleeve slidably received within the mold part over the pin. It has been found that by blow molding the parison with the sleeve initially extended with its end substantially flush with the end of the pin, followed by retracting the sleeve to a retracted position after a predetermined delay time, a boss with a thicker end results. Consequently, the boss end has greater structural integrity, and thus minimizes or eliminates the possibility of penetration and/or cracking of the boss end when a screw is threadedly received in the hollow boss.

Abstract: A method for separating a feedstock comprising hydrogen sulfide, methyl mercaptan, methanol, and water in which a sufficient amount of water is injected into the fractionating column above the feedstock inlet to water wash the organic phase, decanting water and methanol from a tray below the feedstock inlet so that the stream comprising hydrogen sulfide and a minimum of water can be removed overhead and a stream comprising methyl mercaptan and a minimum of water can be removed as bottoms.