Abstract: A compliant column sheath assembly for use in a gas chromatograph is provided which includes an open tubular column in the form of a helical coil having a coiled lengt of between about 5 and 15 cm. The sheath assembly further includes an insulating sheath which surrounds the open tubular column and a frame. When incorporated in a gas chromatograph, the compliant column sheath assembly allows samples to be analyzed in about 2 to 10 seconds.

Abstract: Detection apparatus including an IMS detector (1, 100) or the like has a gas inlet (10) with a gas flow path arrangement (40, 41, 102) by which sample gas is supplied to the detector. In one arrangement two regions (40 and 41) of a gas flow path arrangement are connected in parallel. The regions are provided by respective GC capillary tubing coils (40) and (41) coated internally with materials of different absorption characteristics so that the time taken for the chemical of interest to reach the detector (1) is different along the two coils, thereby giving responses in the detector at different times. Alternatively, two regions of a gas flow path could be provided by regions (104 and 106) arranged serially one after the other.

Abstract: A method and apparatus for detecting a flow disruption within a gas chromatograph (GC) inlet. A controller controls an input flow of a gas entering a chamber of the GC inlet, and the output flow of gas leaving the chamber. A flow disruption is detected when at least one of the input and output flows deviates from a target value.

Abstract: An automated system for processing a liquid test sample is provided.

Abstract: Disclosed are systems and methods that include a thermal desorption unit, a chromatographic column, and an interface device between the unit and the column. The interface device controls the fluid flowing into the column, such as by providing additional carrier gas to maintain a substantially constant gas flow or velocity, by proving a controlled temperature increase, or by venting a portion of the gas received from the thermal desorption unit, thereby removing the dependence on the thermal desorption unit for such control. In some embodiments, the interface is a chromatographic injector. In certain embodiments, a transfer line from the desorption unit is coupled to the same port of the interface device as the chromatographic column. In some of these embodiments, this is accomplished by employing a special adaptor.

Abstract: The present invention generally recites a method, system and apparatus for fluid analysis and more specifically recites a method system and apparatus for multistage injection of a fluid to be analyzed into a fluid analysis instrument.

Abstract: A liquid gas vaporization and measurement system, and associated method, for efficiently vaporizing a continuous sample of liquid gas, such as liquid natural gas (LNG), and accurately determining the constituent components of the gas. A constant flow of liquid gas sampled from a mass storage device is maintained in a vaporizing device. Within the vaporizing device the liquid gas is flash vaporized within heated narrow tubing. The liquid gas is converted to vapor very quickly as it enters one or more independently operating vaporizer stages within the vaporizing device. The vapor gas is provided to a measuring instrument such as a chromatograph and the individual constituent components and the BTU value of the gas are determined to an accuracy of within +/?0.5 mole percent and 1 BTU, respectively.

Abstract: A vapour generator system (1, 101) for an IMS (4, 104) or other apparatus has a chamber (9, 109) in which vapour is produced. A fan or other flow generator (6, 106) is connected to an inlet (8, 108) of the vapour chamber (9, 109) and its outlet (13, 113) is connected to an adsorbent passage (14, 114), such as formed by a bore through a block (15) of carbon. When the fan (6, 106) is on gas flows through the vapour chamber (9, 109) and the adsorbent passage (14, 114) to the IMS (4, 104) or other outlet, with little vapour being adsorbed in the passage. When the fan (6, 106) is off, any vapour molecules that escape to the adsorbent passage (14, 114) do so at a low rate such that substantially all is adsorbed and no vapour escapes.

Abstract: The present invention is directed to a method for multidimensional gas chromatography for separating the analytes of a complex sample. The method comprises the steps of introducing the sample onto a first column whereby the sample is separated into at least two segments, introducing at least one segment into a heartcut device whereby the segments are selectively separated into at least two heartcut fractions, introducing at least one of the fractions onto a second column whereby at least one fraction is further separated into at least two analytes, introducing at least one analyte from the second column to a gas chromatography connector, introducing the analyte from the connector to a third column, and introducing the analyte from the third column into a detector whereby the analyte is analyzed and identified.

Abstract: Systems and methods for cooling a chromatographic column is disclosed generally, comprising heating a chromatographic column, supplying fluid into the column via the inlet end of the column at an inlet pressure, decreasing the temperature of the column, thereby causing the fluid in the column to contract, and controlling the fluid in the column such that the rate at which the fluid in the column contracts does not exceed the flow rate of the fluid supplied to the column. In certain embodiments, the rate of change of the volume of the fluid in the column as the column temperature decreases is modeled, and the rate of contraction of the gas in the column is estimated therefrom. In some embodiments, the column temperature and/or inlet pressure are controlled by a programmable chromatographic oven.

Abstract: A separation column assembly for a gas chromatograph and the like is provided. The assembly is a self contained unit which allows very rapid heating and cooling of the column.

Abstract: Disclosed is a gas flow path switching unit including a gas passage section with a target gas passage for allowing said target gas to pass therethrough. The target gas passage includes a main passage having a proximal end serving as said gas inlet and a number n of branch passages each provided with a respective gas outlet at a terminal end thereof. The branch passages are formed by repeating two or more times a branching process of branching said main passage into two sub passages at a branch point at a distal end of said main passage and further branching at least one of said sub passages into two sub-sub passages at a branch point defined by a distal end of said sub passage. The target gas passage also includes at least a number n of switching-gas supply passages connected to respective intermediate positions of said n branch passages.

Abstract: This invention is a method and device for use with multi-dimensional chromatography that utilizes partial modulation with multiple secondary retention times. An analyte-bearing sample is subjected to a first dimension of chromatography. Thereafter the separated analyte-bearing sample is diluted with a modulated second carrier such at the analyte-bearing sample is not stopped or its temperature altered. The secondary retention time period at which the modulator cycles is variable among multiple secondary retention time periods to prevent loss of resolution with less complex and/or low boiling point compounds and to prevent loss of data with more complex and/or higher boiling point compounds. The partially modulated analyte-bearing sample then feeds into a secondary column where the analyte-bearing sample is further separated.

Abstract: There is provided a rotary valve for fluid analytical systems. The present valve provides improved characteristics such as an extended lifetime. The valve can fulfil different fluid analytical functions and can be a multi-ports and/or multi-positions valve. The valve is provided with extra recesses in the rotor and extra ports in the stator. These recesses allow to cancel the effect of any possible leaks by evacuating them. Such a valve then prevents cross-port leaks and can advantageously be used in highly critical applications. Moreover, the present valve can be used in an analytical system which is advantageously self-diagnostic.

Abstract: A thermal conductivity detector comprises a housing having an internal cavity, a fluid inlet, a fluid outlet, a first bore and a second bore. The thermal conductivity detector further comprises a thermistor having a first electrical lead and a second electrical lead, a first contact pin in electrical communication with said first electrical lead and a second contact pin in electrical communication with said second electrical lead. The first contact pin is oriented within the first bore, the second contact pin is oriented within the second bore and the thermistor is suspended within the gas analysis chamber.

Abstract: A thin film sensor, such as a glucose sensor, is provided for transcutaneous placement at a selected site within the body of a patient. The sensor includes several sensor layers that include conductive layers and includes a proximal segment defining conductive contacts adapted for electrical connection to a suitable monitor, and a distal segment with sensor electrodes for transcutaneous placement. The sensor electrode layers are disposed generally above each other, for example with the reference electrode above the working electrode and the working electrode above the counter electrode. The electrode layers are separated by dielectric layer.

Abstract: A system for controlling the flow rate into a chromatographic column is disclosed generally comprising communicating a fluid to the column through a transfer line, measuring the transfer line inlet pressure, determining the transfer line outlet pressure, and adjusting the applied pressure until the inlet and outlet pressures produce a desired flow rate for the transfer line outlet. In certain embodiments, the applied pressure is adjusted by controlling a proportional valve. In some embodiments, the outlet pressure is determined by measuring the pressure difference across the transfer line and calculating the transfer line outlet pressure from the measured inlet pressure and the pressure difference.

Abstract: Embodiments of the present invention relate to a gas sensor comprising a flow channel, a concentration modulator positioned in the flow channel, a gas generator in contact with the flow channel, one or more gas detectors positioned downstream of the concentration modulator and gas generator and a pump.

Abstract: An improved chromatographic method for measuring impurities in a gas sample that allows extraction of a peak of impurity masked by the sample background. An impurity peak is extracted from the sample background and put in a second sample loop and the second sample loop volume is injected into a second separation column. A “slice” is taken from the sample background to fill the second sample loop and the “slice”, whose width is preferably substantially equal to the impurities peak width, is injected into the second separation column. Another embodiment allows concentration of a predetermined impurity, thereby providing an improved precision on the results. The chromatographic method provides an improved measure of argon in oxygen, oxygen in argon and oxygen in hydrogen.

Abstract: A flow regulator device for an analytical circuit, characterised by comprising: a fluid restriction (R) of defined characteristics related to the field of application of the analytical circuit, a direct-pressure regulator (2) positioned upstream of said restriction (R), a back pressure regulator (4) positioned downstream of said restriction (R).

Abstract: Disclosed are systems and methods that include providing a vessel having an inlet and an outlet for communicating a carrier gas through the vessel; determining a differential pressure between the inlet and the outlet for a known flow rate at the outlet; and, determining a unit flow per unit pressure based on a ratio of the flow rate and the differential pressure. In certain embodiments, the flow rate at the outlet is established by controlling the flow rate of the gas. In some embodiments, the methods and systems can include a viscosity in the ratio, determining a flow rate at ambient pressure using a factor based on a ratio of a gas pressure at the output and ambient pressure, and/or, determining a flow rate at ambient temperature using a factor based on a ratio of a temperature at the output and ambient temperature.

Abstract: A method for obtaining reproducibility of the retention times of the components of a mixture to be analysed in an apparatus for gaschromatographic analysis provided with a capillary column, when there occurs one of the following variations: variation in the length of the column, or alternatively its replacement with a column having identical real specifications with the exception of the length, and/or variation in the pressure of the carrier gas at output from said column. The method envisages that the pneumatic resistance of the column is known and preferably measured before and after the aforesaid variations, and that a new input pressure or a new mass flow of the carrier gas will be entered into said apparatus for gaschromatographic analysis in relation to said values of pneumatic resistance.

Abstract: A method and apparatus for detecting a flow disruption within a gas chromatograph (GC) inlet. A controller controls an input flow of a gas entering a chamber of the GC inlet, and the output flow of gas leaving the chamber. A flow disruption is detected when at least one of the input and output flows deviates from a target value.

Abstract: A self-contained chromatography system is provided and includes a chromatography column, a carrier gas reservoir containing a carrier gas and an analyte stream processing device, wherein the carrier gas reservoir is disposed upstream from the chromatography column and wherein the analyte stream processing device is disposed downstream from the chromatography column. A method for implementing the self-contained chromatography system is also provided and includes generating a first system pressure upstream from the chromatography column and a second system pressure downstream from the chromatography column to cause the carrier gas to flow between the carrier gas reservoir and the analyte stream processing device. The method further includes combining a sample material with the carrier gas, introducing the combined sample to the chromatography column to generate the analyte stream and processing the analyte stream via the analyte stream processing device.

Abstract: A self-contained micro-scale gas chromatography system that includes a plurality of gas chromatography components arranged on a micro-fluidic platform with nearly zero dead volume “tubeless” fluidic connections for the gas chromatography components. The micro-fluidic platform includes a plurality of flow channels that provide fluid flow paths for a sample, carrier gas and waste gas through and among the micro-fluidic platform and the plurality of gas chromatography components. The gas chromatography components may include a micro-scale gas chromatography column that is implemented as a MEMS device and includes embedded heating and cooling elements. The system may also include an on-board supply of carrier gas and on-board waste management, as well as a thermal management scheme making the system suitable for use in oil and gas wells and also other remote environments.

Abstract: A self-contained micro-scale gas chromatography system that includes a plurality of gas chromatography components arranged on a micro-fluidic platform with nearly zero dead volume “tubeless” fluidic connections for the gas chromatography components. The micro-fluidic platform includes a plurality of flow channels that provide fluid flow paths for a sample, carrier gas and waste gas through and among the micro-fluidic platform and the plurality of gas chromatography components. The system may also include an on-board supply of carrier gas and on-board waste management, as well as a thermal management scheme making the system suitable for use in oil and gas wells and also other remote environments.

Abstract: An analyzer includes a reforming unit which reforms fuel containing an organic compound which contains carbon and hydrogen into a reformed gas containing hydrogen, a flame ionization detector which is connected to the reforming unit, and detects an ion generated by combusting the reformed gas supplied from the reforming unit and a sample gas, or ionizing a sample gas by reaction with the reformed gas supplied from the reforming unit, and outputs an output signal representing the ionic amount, and an analysis controller which analyzes the output signal from the flame ionization detector, and provides data capable of identifying a component contained in the sample gas.

Abstract: The present invention is directed to an apparatus and a method for continuously removing water vapor from a closed loop, re-circulated gas flow in an ion mobility spectrometer using a water permeable membrane, having a first side and a second side opposite the first side. The gas flow is disposed adjacent and carried past the first side to deposit water vapor that passes through the membrane to the second side. An exhaust flow is disposed adjacent and carried passed the second side of the membrane to remove the water vapor from the system. Therefore, the water removal apparatus continuously regenerates in-situ. Heaters, heat sinks and additional treatment systems including charcoal filters can also be included in the system to enhance its performance.

Abstract: A multi-purpose modular pyrolysis and thermal processing system (MPMPTPS) for pyrolyzing and/or vaporizing liquids and solids to create an evolved vapor suitable for introduction into a gas-chromatography and/or vapor detection system, thereby allowing detection, classification and/or identification characteristics of threat agents. The MPMPTPS system is capable of pyrolyzing and/or vaporizing liquid (in solution, suspension or colloidal form) and solid (in aerosol or powder form) form of biological and chemical threat agents in a manner that the evolved vapor may be introduced into Gas-Chromatography systems and/or vapor detection systems, without the use of any reagents and/or bottled gases.

Abstract: A hand-held, ultra-sensitive gas chromatograph which provides real time detection and analysis of chemical compounds or impurities is disclosed. The detection sensitivity ranges from parts per trillion to parts per million with an average retention time ranging from thirty to forty-five seconds. Optimum calculated effective plate number is 55,000, with a response time on the order of two minutes. The self-contained apparatus operates on twenty-four watts, weighs twelve pounds, and measures 8?×6?×13.

Abstract: A multi-purpose modular pyrolysis and thermal processing system (MPMPTPS) for pyrolyzing and/or vaporizing liquids and solids to create an evolved vapor suitable for introduction into a gas-chromatography and/or vapor detection system, thereby allowing detection, classification and/or identification characteristics of threat agents. The MPMPTPS system is capable of pyrolyzing and/or vaporizing liquid (in solution, suspension or colloidal form) and solid (in aerosol or powder form) form of biological and chemical threat agents in a manner that the evolved vapor may be introduced into Gas-Chromatography systems and/or vapor detection systems, without the use of any reagents and/or bottled gases.

Abstract: Integrated nanotube sensors are adapted for detecting various chemical and biological molecules. In one implementation, nanotube sensor arrays are formed as nano-electronic noses capable of such detection, and can be implemented in devices including carbon nanotube-based electronic noses and biochips. Various implementations of the present invention are also directed to nanoscience and nanotechnology applications, such as medical, military and biological applications. In a more particular implementation, nanotubes are produced on full-scale wafers and functionalized. In another more particular implementation, functionalized nanotubes are integrated into addressable devices. With these approaches, various aspects of the present invention have been found to be useful in sensor applications having small size, high density and extreme sensitivity. Such sensor applications are applicable to many aspects of society, and can be implemented for making human lives more safe, secure and healthy.

Abstract: An inlet seal assembly for sealing an injection port member in a chromatography instrument , comprising an injection port member having a raised metal ring, an inlet seal member with an upper surface, a peripheral groove formed in the inlet seal member upper surface, a soft resinous plastic material ring positioned in the peripheral groove opposite the raised metal sealing ring, a reducing nut holding the inlet seal member against the injection port member, and threads connecting the reducing nut to the injection port member whereby to press the soft ring against the raised metal sealing ring to form a seal. The inlet seal assembly also may have a bottom seal between the inlet seal member and the reducing nut. A method of making and using the inlet seal assembly.

Abstract: A method for coupling a gas chromatograph (21) to an NMR spectrometer, wherein the carrier gas present at the outlet of a separating column (23) of the gas chromatograph (21) including a sample contained in the carrier gas is supplied via a heated transfer line (1) to a collecting device (2) for the sample contained in the carrier gas, is characterized in that the carrier gas containing the sample is introduced into a collecting liquid (8) in the collecting device (2), and the sample is collected in the collecting liquid (8), wherein the collecting liquid (8) is suitable as an NMR solvent for the sample. The sample loss of the coupling method is reduced.

Abstract: A thermal modulator device for gas chromatography and associated methods. The thermal modulator device includes a recirculating fluid cooling member, an electrically conductive capillary in direct thermal contact with the cooling member, and a power supply electrically coupled to the capillary and operable for controlled resistive heating of the capillary. The capillary can include more than one separate thermally modulated sections.

Abstract: The present invention relates generally to a method and apparatus for real-time environmental gas sampling. A manifold is disclosed allowing for real-time gas sampling and monitoring/analysis of atomospheric over a wide range of oxygen contents, e.g., oxygen-rich as well as oxygen-deficient sampling environments in conjunction with mass-sepectrometric analysis achieving detection limits as low as single part per-billion.

Abstract: Disclosed are systems and methods that include a thermal desorption unit, a chromatographic column, and an interface device between the unit and the column. The interface device controls the fluid flowing into the column, such as by providing additional carrier gas to maintain a substantially constant gas flow or velocity, by proving a controlled temperature increase, or by venting a portion of the gas received from the thermal desorption unit, thereby removing the dependence on the thermal desorption unit for such control. In some embodiments, the interface is a chromatographic injector. In certain embodiments, a transfer line from the desorption unit is coupled to the same port of the interface device as the chromatographic column. In some of these embodiments, this is accomplished by employing a special adaptor.

Abstract: A thermal modulator device for gas chromatography and associated methods. The thermal modulator device includes a cooling member, an electrically conductive capillary in direct thermal contact with the cooling member, and a power supply electrically coupled to the capillary and operable for controlled resistive heating of the capillary.

Abstract: Gas chromatographs of the invention generally comprise four or more analysis channels. Specifically, four or more gas chromatography columns are configured for parallel analysis of four or more gaseous samples with detection being effected using a microdetector array comprising four or more microdetectors. In one embodiment, the four or more microdetectors 510 are microfabricated detectors, and are integrally formed with a substrate or with one or more microchip bodies mounted on a substrate. In a preferred embodiment, a microdetector array comprises four or more thermal conductivity detectors having one or more thin-film detection filaments. A preferred heated environment for highly parallel gas chromatographs is also disclosed.

Abstract: A chemical vapor sensor is provided that measures a chemical species of interest with high sensitivity and chemical specificity. In an aspect, an ethanol vapor sensor is provided, sized for being inconspicuous and on-board a vehicle, having a passive measurement mode and an active breathalyzer mode, for detecting a motor vehicle driver that exceeds a legal limit of blood alcohol concentration (BAC), for use with vehicle safety systems. For the passive mode, a vapor concentrator is utilized to amplify a sampled vapor concentration to a detectible level for use with an infrared (IR) detector. In an aspect, ethanol vapor in a vehicle cabin is passively measured and if a predetermined ethanol level is measured, a countermeasure is invoked to improve safety. In an aspect, an active breathalyzer is used as a countermeasure. The active breathalyzer can be imposed for a number of vehicle trips or for a predetermined time period.

Abstract: The present invention is an improvement to two-dimensional comprehensive gas chromatography. The improvement is a two-valve switching modulator connecting two different type of separation columns. The advantages of current invention are (1) a simple system can be built by readily available parts; (2) no specific materials required (other than electricity) to operate the system, especially, do not need any type of coolant; (3) can be build on any GC as an externally added on unit; (4) The first and the second dimensional column flow are independently controlled, it is easier to design the experiment; and (5) it is cost effective, the cost of building this system is inexpensive than other type of modulation.

Abstract: A gas chromatography/mass spectrometry system includes two sample introduction parts, a gas chromatography part having two columns, a column oven for housing the two columns in a parallel configuration, an interface part through which an outlet end of each of the two columns is inserted, and a mass spectrometry part. The mass spectrometry part has an ionization chamber to which the outlet ends of the columns inserted through the interface part are connected, a mass separation part, an ion detector, and a vacuum chamber for housing the ionization chamber, the mass separation part, and the detector. Because the outlet ends of the parallel columns are both connected to the ionization chamber, the carrier gas flow and line velocity are the same as though there is one column, thereby avoiding line stagnation. Since analyses can be performed selectively with a single system, results having high reliability and precision can be obtained.

Abstract: An electronically controlled back pressure regulator comprises an analysis device having a vent coupled to the analysis device through a vent path, a pressure sensor coupled to the vent path, a proportional valve coupled to the vent path, the proportional valve configured to controllably alter pressure in the analysis device, and an electronically controlled closed-loop controller configured to control a flow through the vent based on a signal from the pressure sensor and an electronically controlled pressure setpoint.

Abstract: A system which enables the presentation of alternating gas samples to a gas sensor in a detection zone without substantial change of the sample pressure at the sensor in the zone, whereby pressure variations that can produce unwanted sensor signals are mitigated; along with apparatus for facilitating, and a method for implementing, the foregoing.

Abstract: Disclosed are systems and methods that include a sampling device, a chromatographic column, and a transfer line through which a fluid containing analytes to be measured are communicated from the sampling device to the column. The pressure at which the fluid containing the analytes is applied at the inlet of the transfer line is adjusted as the temperature of the column increases in accordance with certain relationships in order to maintain a substantially constant flow rate or velocity for the fluid exiting the column. In this way, the system compensates for changes in the viscosity of the fluid flowing through the column that result from changes in the column temperature.

Abstract: There is provided a diaphragm sealed valve particularly advantageous in chromatographic systems. The valve is provided with first and second body and a seal member compressibly positioned therebetween. The first body comprises a first, a second and a common port, each opening and being interconnected to the others in a recessed fluid communication channel extending in a first interface of the first body. The valve is also provided with first and second plungers, each having a closed position wherein the plunger presses down the seal member against the seat of the corresponding port for closing said corresponding port, and an open position wherein the plunger extends away from the seat for allowing a fluid communication between the corresponding port and the channel. Complex valves are also provided as well as chromatographic systems and methods.

Abstract: A gas chromatograph having the capability of performing a reliable measurement under a condition that the baseline of a detector output is stabilized, and a breath component analyzer using the same are provided. This gas chromatograph comprises a gas separation column accommodating a member for causing a flow delay depending on gas component; air pump for supplying an air as a carrier gas into the gas separation column; gas supply port formed in a gas flow channel extending between the air pump and the gas separation column, and adapted to supply a subject gas containing a target gas component to be detected into the carrier gas flowing in the gas flow channel; buffer tank provided upstream of the gas supply port; and a detector for detecting the gas component of the subject gas supplied into the gas separation column.

Abstract: Disclosed are systems and methods that include providing a vessel having an adsorbent disposed therein, the vessel having an inlet and an outlet for communicating a carrier gas through the vessel; determining a differential pressure between the inlet and the outlet for a known flow rate at the outlet; and, determining a geometric measure for the vessel based on a ratio of the known flow rate and the differential pressure. In some embodiments, the methods and systems can include a viscosity in the ratio, determining a flow rate at ambient pressure using a factor based on a ratio of a gas pressure at the output and ambient pressure, and/or, determining a flow rate at ambient temperature using a factor based on a ratio of a temperature at the output and ambient temperature.

Abstract: An instrument including a chromatographic column with a final detector and a mass spectrometer. A temperature of an interface including an output tube and a capillary tube adjusting the flow to the spectrometer is adjusted using a leakage flow or pressure sensor outputting data to a control module that adjusts the interface temperature to equalize flows in the tubes.

Abstract: A gas chromatograph set of the present invention comprises a plurality of gas chromatographs and a flow passage assembly. Each of the gas chromatographs includes a column for separating sample-components, a carrier gas supply unit for supplying a carrier gas to the column and a detector for detecting eluted components from the column. The carrier gas supply unit comprises a carrier gas passage, and a flow controller unit for controlling a flow-rate that is connected to the carrier gas passage. The flow passage assembly comprises a metal plate inside which the carrier gas passages of the gas chromatographs are formed.