Abstract: A method to measure the concentration of a constituent element in a gas sample contained in an analyzer. A sample cell of a detector has an inlet and an outlet. The outlet of the sample cell is sealed. A predetermined mass of a gas sample is received through the inlet into the sample cell over a predetermined pressurization period until substantially the entire mass of the gas sample contained in the analyzer is contained within the sample cell. The gas sample is pressurized to a predetermined pressure over the pressurization period. A concentration of a constituent element in the pressurized gas sample is determined.

Abstract: A purge and trap concentrator has a sample processing system that includes a network of fluid passageways and fluid control devices. A flow controller couples to a purge gas inlet provides an electrically adjustable purge gas flow rate as a function of an electrical input. A digital controller provides the system cycle and provides the electrical input. The electrical input varies as a function of the system cycle to increase the rate of flow of purge gas during a bake step relative to the rate of flow of purge gas during a purge step in the system cycle.

Abstract: A purge and trap concentrator and a method for drying a stream of sample gas in a gas analysis instrument. A dryer tube has an inlet that receives a stream of sample gas during a drying interval and receives a stream of dry gas during a regeneration interval. The dryer tube also has an outlet and an interior passageway between the inlet and an outlet. Support material comprising polymer sorbent is placed in the interior passageway and provides a support surface area for a hygroscopic coating comprising lithium chloride. A controller controls a heater to increase the temperature of the dryer tube to between 100 and 300 degrees centigrade during the regeneration interval and controls the heater to decrease the temperature of the dryer tube to below 100 degrees centigrade during the drying interval.

Abstract: A vial autosampler includes a vial cup adapted to contain a vial with a stir member inside. The vial autosampler includes a vial mixing system for agitating the contents of the vial. The mixing system has an actuator, such as a motor, and a mixing hub that is coupled to the actuator. The mixing hub includes at least one magnetic field source disposed to rotate a magnetic field about the vial cup.

Abstract: A purge and trap concentrator and a method for drying a stream of sample gas in a gas analysis instrument. A dryer tube has an inlet that receives a stream of sample gas during a drying interval and receives a stream of dry gas during a regeneration interval. The dryer tube also has an outlet and an interior passageway between the inlet and an outlet. Support material comprising polymer sorbent is placed in the interior passageway and provides a support surface area for a hygroscopic coating comprising lithium chloride. A controller controls a heater to increase the temperature of the dryer tube to between 100 and 300 degrees centigrade during the regeneration interval and controls the heater to decrease the temperature of the dryer tube to below 100 degrees centigrade during the drying interval.

Abstract: A three stage needle for use with a sampling station of an autosampler to facilitate gas and liquid extractions and injections. The needle includes a bottom stage, a middle stage, and a top stage. Each of the stages of the needle includes at least one aperture used to extract gas or liquid from a specimen or perform an injection. In addition, each of the stages can be placed in fluidic communication with the sampling station to facilitate the desired extraction or injection.

Abstract: A system for concentrating a volatile organic compound (VOC) sample uses in one embodiment a bypass line and a valve coupled thereto to regulate an amount of carrier gas flowing through a carrier gas line. A flow splitter fluidly couples the bypass line to the carrier gas line, and connects to the output of a cryofocuser. The valve opens at the onset of transferring the VOC sample from a concentrator trap such as a sorbent trap to the cryofocuser, thereby resulting in an increased amount of carrier gas flow between the concentrator trap and the cryofocuser for more efficient desorbing of the concentrator trap. The valve is closed when the focused VOC sample is flushed out of the cryofocuser for delivery to a gas chromatograph, preferably delivering the entire VOC sample to the GC.

Abstract: A modular vial autosampler has a storage area for vials containing samples to be analyzed and at least one modular sampling station. A vial transfer mechanism includes an arm having a gripper that lifts a sample vial from the storage section, and the arm moves it to a station for identification and then to a sampling station, and under central control activates the sampling station for obtaining a sample for analysis. The vial transfer mechanism gripper is movable in X, Y, and Z directions to capture and move a selected vial and includes an alignment guide for the vials. Potentiometers are used for providing signals indicating arm position and the control is provided with updated information for calibration of the potentiometers and also updated position information for the arm relative to a fixed home position is obtained.

Abstract: A modular vial autosampler has a storage area for vials containing samples to be analyzed and at least one modular sampling station. A vial transfer mechanism includes an arm having a gripper that lifts a sample vial from the storage section, and the arm moves it to a station for identification and then to a sampling station, and under central control activates the sampling station for obtaining a sample for analysis. The vial transfer mechanism gripper is movable in X, Y, and Z directions to capture and move a selected vial and includes an alignment guide for the vials. Potentiometers are used for providing signals indicating arm position and the control is provided with updated information for calibration of the potentiometers and also updated position information for the arm relative to a fixed home position is obtained.

Abstract: A carbon analyzer, is provided which includes a combustion chamber having a platinum on titania catalyst. The combustion chamber and catalyst are also provided. A method for analyzing carbon-containing specimens with such an analyzer is also provided as well as a method for oxidizing such specimens with a platinum on titania catalyst. A method of conditioning the catalyst is also provided.

Abstract: A device for rinsing sample processing components of an analytical instruments including an inlet coupleable to a fluid source, an outlet coupleable to sample processing components of an analytical instrument, and a fluid reservoir between the inlet and outlet. The device includes a heater coupled to the fluid reservoir and the fluid reservoir includes at least two reservoir chambers connected in series and separated by a restricted passageway.

Abstract: A sample transport device for use in analyzing samples by the headspace analysis technique. The device has a cylindrical platen with counterbored chambers for accepting sample vials. The platen is heated and caused to rotate from a first vial transport point to a sampling point and then back for ejection of the sample vial. Vertical movement of the sample vials is accomplished by use of elevator rods connected to level winding screws mounted below the cylindrical platen. The device has a mechanism for agitating the vials in the platen chambers during transport to the sampling point.

Abstract: A method of preparing a volatile sample from a material for gas chromatographic analysis includes the steps of: introducing a vial with the material containing the volatile sample and a headspace therein into a chamber of a platen adapted to transport the vial to a location for removal of at least a portion of the volatile sample for gas chromatographic analysis; heating the material containing the volatile sample while the vial is being transported to the location for removal; agitating the vial while in the chamber to enhance a transport rate of the volatile sample from the material to the headspace of the vial; and introducing a needle to the vial to withdraw at least a portion of the volatile sample from the headspace of the vial.

Abstract: A modular vial autosampler has a storage area for vials containing samples to be analyzed and at least one modular sampling station. A vial transfer mechanism lifts a sample vial from the storage section, moves it to a station for identification and then to a sampling station, and under central control activates the sampling station for obtaining a sample for analysis. The vial transfer mechanism is movable in x, y, and z directions to capture and move a selected vial. The autosampler has a series of valves operable under central control to selectively introduce two different standards into the sample, and after obtaining the sample, for rinsing and purging the conduits or lines and needles to reduce sample carryover. The modular vial autosampler includes controls to selectively sample either a gas or a liquid using many of the same components.

Abstract: A modular vial autosampler has a storage area for vials containing samples to be analyzed and at least one modular sampling station. A vial transfer mechanism lifts a sample vial from the storage section, moves it to a station for identification and then to a sampling station, and under central control activates the sampling station for obtaining a sample for analysis. The vial transfer mechanism is movable in x, y, and z directions to capture and move a selected vial. The autosampler has a series of valves operable under central control to selectively introduce two different standards into the sample, and after obtaining the sample, for rinsing and purging the conduits or lines and needles to reduce sample carryover. The modular vial autosampler includes controls to selectively sample either a gas or a liquid using many of the same components.

Abstract: A modular vial autosampler has a storage area for vials containing samples to be analyzed and at least one modular sampling station. A vial transfer mechanism lifts a sample vial from the storage section, moves it to a station for identification and then to a sampling station, and under central control activates the sampling station for obtaining a sample for analysis. The vial transfer mechanism is movable in x, y, and z directions to capture and move a selected vial. The autosampler has a series of valves operable under central control to selectively introduce two different standards into the sample, and after obtaining the sample, for rinsing and purging the conduits or lines and needles to reduce sample carryover. The modular vial autosampler includes controls to selectively sample either a gas or a liquid using many of the same components.

Abstract: An analytical instrument measures carbon content of a liquid sample. The instrument includes a sample inlet, a reagent inlet, a rinsing solution inlet, a reaction chamber, a waste outlet and a syringe pump. A multiple port valve has a plurality of ports which are coupled to the sample inlet, the reagent inlet, the rinse solution inlet, the reaction chamber and the waste outlet. The valve also includes a primary port coupled to the syringe pump and selectively fluidically couplable to each of the remaining ports.

Abstract: A modular vial autosampler has a storage area for vials containing samples to be analyzed and at least one modular sampling station. A vial transfer mechanism lifts a sample vial from the storage section, moves it to a station for identification and then to a sampling station, and under central control activates the sampling station for obtaining a sample for analysis. The vial transfer mechanism is movable in x, y, and z directions to capture and move a selected vial. The autosampler has a series of valves operable under central control to selectively introduce two different standards into the sample, and after obtaining the sample, for rinsing and purging the conduits or lines and needles to reduce sample carryover. The modular vial autosampler includes controls to selectively sample either a gas or a liquid using many of the same components.

Abstract: A modular vial autosampler has a storage area for vials containing samples to be analyzed and at least one modular sampling station. A vial transfer mechanism lifts a sample vial from the storage section, moves it to a station for identification and then to a sampling station, and under central control activates the sampling station for obtaining a sample for analysis. The vial transfer mechanism is movable in x, y, and z directions to capture and move a selected vial. The autosampler has a series of valves operable under central control to selectively introduce two different standards into the sample, and after obtaining the sample, for rinsing and purging the conduits or lines and needles to reduce sample carryover. The modular vial autosampler includes controls to selectively sample either a gas or a liquid using many of the same components.