Abstract: A sample injector for a chromatography system is configured for injecting a sample fluid into a mobile phase, and includes a needle and a conduit. The needle is configured for aspirating the sample fluid and includes a needle tip, a needle channel through the needle for guiding the aspirated sample fluid, and a needle opening at the needle tip into which the needle channel opens. The conduit is configured for fluidically coupling with the needle and includes a conduit tip, and a conduit channel through the conduit for guiding fluid and having a conduit opening at the conduit tip. The conduit tip and the needle tip are configured to be pressed against each other for fluidically coupling the conduit channel with the needle channel, with at least a portion of the conduit tip penetrating into the needle opening for providing the fluidic coupling between the conduit and needle channels.

Abstract: The disclosed system and method improve analysis of chemical samples for measurement of trace volatile chemicals, such as by Gas Chromatography (GC) and Gas Chromatography/Mass Spectrometry (GCMS). The system can include two traps in series, the first of which removes most of the unwanted water vapor, while the second trap preconcentrates the sample using a series of capillary columns of increasing adsorption strength. The sample can be backflushed from the second trap directly to a chemical analyzer without splitting which can maximize sensitivity. The system improves elimination of water vapor and fixed gases from the sample prior to analysis, resulting in detection limits as low as 0.001 PPBb. The second trap allows faster release of the sample upon injection to the chemical analyzer without additional focusing, and can be cleaned up faster when exposed to high concentration samples relative to packed traps.

Abstract: A flow controller having high workability and a gas chromatograph equipped with the same are provided. A carrier gas controller is equipped with a flow path member. The flow path member is equipped with a first portion and a second portion extending horizontally from an upper end portion of the first portion. In the second portion, a gas outlet port is formed. An H2 gas controller is equipped with a flow path member. The flow path member is equipped with a first portion and a second portion extending horizontally from an upper end portion of the first portion. In the second portion, a gas outlet port is formed. For this reason, a sufficient working space for the gas outlet port can be secured. Further, a sufficient working space for the gas outlet port can be secured. In other words, the workability with respect to the carrier gas controller and the H2 gas controller can be kept high.

Abstract: A sampling system includes an analyte sampler that includes an enclosure; a mount disposed in the enclosure; a capillary tube disposed in the mount; and a thermal member disposed in the enclosure and including a first fluid supply member to provide a fluid to an interior of the enclosure. The sampling system also includes a manifold in fluid communication with the analyte sampler. A process for sampling an analyte includes subjecting the capillary tube to a negative pressure; and controlling the temperature of the capillary tube to immobilize the analyte in the capillary tube; providing an analyte to a second end of the capillary tube; and immobilizing the analyte in the capillary tube to sample the analyte.

Abstract: Exemplary embodiments of the present disclosure include systems, apparatuses, and methods that are directed to controlling pressure in a pressurized flow system, such as a C02-based chromatography system or other pressurized flow systems. Exemplary embodiments of the present disclosure comprise one or more apparatuses, systems or methods for implementing multiple pressure regulators to control pressure. In addition to providing pressure control, apparatuses, systems and methods described herein dampen damaging thermal effects caused by pressure drops of a mobile phase including C02.

Abstract: The present disclosure provides adaptive methods for gas chromatography analysis of a gas sample comprising one or more target analytes (such as a micro-gas chromatography) and adaptive gas chromatography devices for carrying out such analytical methods. Broadly, the system can regulate flow into a downstream chromatographic column by detecting one or more upstream conditions. For example, one adaptive chromatography device comprises a first column, a modulator component, and a second column. A first detector or sensor detects the presence of target analytes upstream from the second column, while a second detector detects the presence of target analytes eluted from the second column. The modulator component assembly is responsive to an output generated by the first detector and adaptively regulates fluid flow into the second column. Such adaptive chromatography (micro-GC) systems have higher separation speed, better analyte identification capability, and far greater energy savings.

Abstract: A housing of a column unit is tubular-shaped, and includes a first opening and a second opening, and an inner space separated from outside air by an insulating material. An air cooling section including a cooling device is arranged on a side of the first opening of the housing. At the time of cooling the inside of the inner space of the housing, air is caused, by a fan, to flow through the air cooling section and from the side of the first opening to a side of the second opening. A column section including a separation column and a heater is arranged inside the housing. A gap through which air flows from the first opening to the second opening is formed between the column section and an inner wall of the inner space of the housing.

Abstract: Embodiments of an apparatus including a front-end pre-concentrator module including an inlet, an outlet, and at least one valve to control flow through the inlet, the outlet, or both. The apparatus includes a back-end pre-concentrator module including an inlet, an outlet, and at least one valve to control flow through the inlet, the outlet, or both, and also includes a gas analysis module having an inlet and an outlet and including a gas chromatograph having an inlet and an outlet. The outlet of the front-end pre-concentrator and the outlet of the back-end pre-concentrator are coupled to the inlet of the gas analysis module. Other embodiments are also disclosed and claimed.

Abstract: A method for abating effluent from an electronic device manufacturing process is provided, including abating the effluent in a thermal abatement tool to form abated effluent; determining whether the abated effluent contains one or more chemical species of interest; and changing one or more operating parameters of the thermal abatement tool based upon the determination. Numerous other embodiments are provided.

Abstract: An apparatus and process for recovering a desired gas such as xenon difluoride, xenon, argon, helium or neon, from the effluent of a chemical process reactor that utilizes such gases alone or in a gas mixture or in a molecule that becomes decomposed wherein the chemical process reactor uses a sequence of different gas composition not all of which contain the desired gas and the desired gas is captured and recovered substantially only during the time the desired gas is in the effluent.

Abstract: A multicapillary bundle for use in a gas chromatograph. Each of the capillaries in the bundle is formed using a coating solution containing a stationary phase and a solvent. The capillaries are coated with stationary phase by reducing pressure at a vacuum end of the capillary and creating a moving interface between the coating solution and a film of stationary phase deposited on each of the capillaries. The reducing pressure at the vacuum end of the capillary and the temperature of the capillary are controlled to maintain motion of the moving interface away from the vacuum end of the capillary. Maintained movement of the interface prevents recoating of the stationary phase. A heating wire and capillaries are embedded in a thermally conductive polymer to create a highly responsive method of heating the multicapillary column. An electronic control device controls the feedback temperature of the multicapillary column using the heating wire.

Abstract: The invention is a chromatography apparatus which comprises at least one capillary column, which has a coil assembly of column material and a small diameter wire coated with an electrically insulating high temperature material encased within a high temperature sheath. The small diameter wire is at least one electrically conductive element co-linear with the column material. Also provided is means for directly resistively heating the at least one capillary column, and means for controlling the temperature of the capillary column. Additionally, the apparatus includes an oxygen gas containing inlet, a hydrogen inlet, an analyte port and a flame region, oxygen delivery means for delivering oxygen through the oxygen inlet to the flame region, a hydrogen and analyte delivery system for delivering hydrogen and analyte to the flame region, and a detector arranged to detect flame emission.

Abstract: The present invention refers to a modulator, to be used for comprehensive multidimensional chromatography separations to entrap and release sample solute fractions (entrapped in a capillary loop of fixed or variable volume), deriving from a capillary column with an internal diameter ranging from 0.01 mm to 0.53 mm, onto another capillary column with an internal diameter ranging from 0.01 mm to 0.53 mm. The micro-device has been integrated in a gas chromatographic system, composed of two ovens for the independent temperature control of the two columns; the micro-device is characterized, internally, by a system of channels that enable the controlled splitting of gas flow, entering the second capillary, to generate an optimum gas linear velocity and to release the pressure in excess, with the objective of attaining the maximum separation efficiency in the second column.

Abstract: The invention relates to a device and to a method for determining the proportion of fuel in a combustion engine lubricating oil. The device according to the invention comprises a column (12) with at least 22000 theoretical plates and a steady state phase capable of separating the fuel, the oil, the internal standard contained in the oil and the solvent, in which the oil and the internal standard are diluted, and a heating module (120) capable of causing an increase in the temperature of the column (12) at a rate of at least 350° C./min. In the method according to the invention, the column (12) is subjected to determined cycles during which the pressure of the carrier gas and the temperature are varied.

Abstract: A gas chromatograph (GC) apparatus capable of detecting abnormality, in which a reference retention index is obtained from a result obtained by analyzing a given substance and a retention-index reference substance under adequate analysis conditions using a normal column, and stored in a storage section. Further, under a condition that the apparatus can perform normal analysis, the given substance is subjected to GC analysis to obtain a reference retention time, and the obtained reference retention time is stored in the storage section. A diagnosis processing section is operable to compare each of an actual retention time and an actual retention index with a respective one of the reference retention time and the reference retention index. If a deviation therebetween or abnormality is detected, the diagnosis processing section is operable to estimate a causal factor of the abnormality.

Abstract: An apparatus and method for rapid fractionation of hydrocarbon phases in a sample fluid stream are disclosed. Examples of the disclosed apparatus and method include an assembly of elements in fluid communication with one another including one or more valves and at least one sorbent chamber for removing certain classifications of hydrocarbons and detecting the remaining fractions using a detector. The respective ratios of hydrocarbons are determined by comparison with a non separated fluid stream.

Abstract: A device for providing a constant mass flow rate to a downstream column system of a gas chromatograph includes a small full scale mass flow controller that controls carrier gas to flow at a first mass flow rate and a flow resistance element, including an inlet port connected to a sample inlet, an outlet port connected to the downstream column system, and a pressure sensing port in fluid communication with the outlet port and the mass flow controller. A sample inlet pressure controller controls the sample inlet at a first pressure, and a pressure sensor measures a second pressure of the carrier gas at the pressure sensing port. A set point of the first pressure is determined as a function of the second pressure, flow resistance of the flow resistance element, and a second mass flow rate from the inlet port to the outlet port of the flow resistance element.

Abstract: A system for recycling helium carrier gas comprises: a bladder, the bladder interior fluidically configured so as to receive helium-bearing gas output from at least one of a split vent and a septum purge vent of a gas chromatograph; a compartment containing the bladder; a source of pressurized air or gas operable so as to supply pressurized air or gas into the compartment interior so as to compress the bladder containing the helium-bearing gas; a gas reservoir fluidically coupled to the bladder interior so as to receive the helium bearing gas from the compressed bladder interior; and at least one gas purification module configured so as to receive the helium-bearing gas from the gas reservoir and operable to remove contaminants from the helium-bearing gas, an output of the at least one gas purification module being fluidically coupled to a carrier gas inlet of the gas chromatograph.

Abstract: Systems and methods for performing chromatography separations or analyses are disclosed. The methods are based upon an equilibrium gradient focusing mode in contrast to conventional transient migration-based modes. By matching the migration speed of one or more analyte(s) of interest to the wave speed of a thermal gradient induced to travel along a region in which chromatographic partitioning occurs, significant improvements in detection limits are achieved. In particular, a temperature gradient focusing strategy is described in which analyte(s) of interest are circulated around a continuous chromatography system in order to focus the analyte(s). Also described are various devices and systems that can be used in the methods described herein.

Abstract: A portable gas chromatography system and method of use. The portable gas chromatograph may be used to accurately and rapidly detect low-level concentrations of chemicals, such as fixed gases, volatilized liquid samples, or toxic chemicals and transmit to a user data relating to the presence and identity of such. The portable gas chromatograph uses an onboard vacuum source to pull samples into and through the system and thus does not require the use of a carrier gas. Further, the system comprises a solenoid valve for capturing the sample and may include a short porous layer open tubular separation column, and a thermal conductivity detector. Overall size and weight of the system is small enough for a user to carry. The method of operation of the gas chromatograph includes taking rapid successive samples and analyzing the data outputs using Fourier transform techniques. Such analysis allows real-time data updates and rapid detection of hazardous environmental agents.

Abstract: A portable multi-dimensional gas chromatograph, the gas chromatograph including a carrier gas container, a regulator fluidly connected to the carrier gas container, a dopant chamber containing a reference chemical, at least one pre-concentrator which is fluidly connected to the regulator and the dopant chamber, a first separation column fluidly connected to the at least one pre-concentrator, a second separation column fluidly connected to the at least one pre-concentrator, a first detector fluidly connected to the first separation column, and a second detector fluidly connected to the second separation column.

Abstract: A gas chromatography system comprising a sample introduction device, an oven coupled to the sample introduction device and a detector coupled to the oven is disclosed. In certain examples, the oven may be configured to receive a chromatography column in a space in the oven. In some examples, the oven may be constructed and arranged to provide a substantially constant temperature to the space during an analysis stage of the gas chromatography system.

Abstract: An apparatus and method for rapid fractionation of hydrocarbon phases in a sample fluid stream are disclosed. Examples of the disclosed apparatus and method include an assembly of elements in fluid communication with one another including one or more valves and at least one sorbent chamber for removing certain classifications of hydrocarbons and detecting the remaining fractions using a detector. The respective ratios of hydrocarbons are determined by comparison with a non separated fluid stream.

Abstract: A liquid chromatograph device was provided wherein operations inside a thermostatic chamber can be safely performed even while a heat block is being heated. The liquid chromatograph device comprises: a thermostatic chamber; outer doors and that are disposed at the front surface of the thermostatic chamber; a heat block; heater for heating said heat block; temperature sensor for the heat block; flowing means for flowing air between the inside and outside of the thermostatic chamber; a control means for controlling the supply of power to the heater based on the result of the temperature sensor; and an inner door between the outer door and the heat block, the inner door comprising a hollow inner door main body, a heat-insulating material that is housed within the inner door so as to form an air chamber between the heat-insulating material and the surface of the outer door of the inner door main body and inlet/outlet slits and that are formed in the inner door main body.

Abstract: A microtrap assembly includes a carbon nanotube sorbent. The microtrap assembly may be employed as a preconcentrator operable to deliver a sample to an analytical device to measure the concentrations of greenhouse gases. A system includes a microtrap having a carbon nanotube sorbent for measuring the concentrations of greenhouse gases in a sample.

Abstract: A device for providing a constant mass flow rate to a downstream column system of a gas chromatograph includes a small full scale mass flow controller that controls carrier gas to flow at a first mass flow rate and a flow resistance element, including an inlet port connected to a sample inlet, an outlet port connected to the downstream column system, and a pressure sensing port in fluid communication with the outlet port and the mass flow controller. A sample inlet pressure controller controls the sample inlet at a first pressure, and a pressure sensor measures a second pressure of the carrier gas at the pressure sensing port. A set point of the first pressure is determined as a function of the second pressure, flow resistance of the flow resistance element, and a second mass flow rate from the inlet port to the outlet port of the flow resistance element.

Abstract: A method for degassing a fluid includes providing a degassing system having a degassing module and a fluid pump apparatus having a fluid reservoir, wherein the fluid pump apparatus is operated in a discontinuous mode involving one or more discrete pumping cycles having a first cycle time. The fluid pump apparatus is calibrated to deliver a predetermined volume of the fluid from the fluid reservoir during each of the pumping cycles, and the degassing module is adapted to operably move gas from the fluid to an extent sufficient to render the fluid volume to a desired degassed condition within a period of time that is not greater than the first cycle time.

Abstract: An open probe method for sample introduction into a mass spectrometer is disclosed, comprising the steps of: loading a sample holder with sample compounds to be analyzed; heating a probe oven; introducing said sample compounds in said sample holder into said heated probe oven; flowing inert gas into said heated probe oven; vaporizing said sample in said heated probe oven by the combined effect of oven temperature and inert gas flow; entraining said vaporized sample in said inert gas; and, transferring said vaporized sample in inert gas into an ion source of a mass spectrometer; wherein said heated probe oven remains open to the ambient atmosphere during sample introduction and analysis; said inert gas is flowing in said heated probe oven in two directions of a transfer line to a mass spectrometer ion source and to the oven opening; said vaporized sample in inert gas is transferred through a heated transfer line directly into the ionization chamber of an ion source of a mass spectrometer.

Abstract: A portable weather resistant gas chromatograph system with a gas chromatograph enclosure having a body and a movable door and a seal, a gas chromatograph with a frame assembly removably secured in the enclosure, a plurality of exhaust gas lines connected to the gas chromatograph, an explosion proof terminal box with circuit breakers and terminals mounted to the enclosure, a communication conduit and armored power cable between the explosion proof terminal box and the gas chromatograph, a purge gas conduit port for the gas chromatograph, a pedestal for the enclosure, and at least two lifting eyes connected to the enclosure.

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: An apparatus, system, and method are disclosed for a gas chromatography (GC) system with a check valve. The check valve is situated downstream from the electronic flow control module and upstream of the injector. When a sample is volatized in the injector, the check valve closes into a checked position and prevents solvent and sample from backing into the gas delivery line. In certain embodiments, the check valve has a conical plug that fits into a seat that has an aperture. When the conical plug is depressed, the conical plug engages the sides of the aperture and seals the check valve, preventing solvent and sample from backing through the check valve. In certain embodiments, the change in pressure caused by over-pressurization in the injector, combined with the force applied by a spring on the conical plug, depresses the plug such that it seals the aperture.

Abstract: An apparatus, system, and method are disclosed for broad spectrum chemical detection. The method includes detecting an ambient temperature and setting a target temperature based on the ambient temperature. The target temperature is a temperature greater than the ambient temperature. The method further includes determining elution data for the target temperature, either by selecting a target temperature at which elution data is available, or by interpolating between available sets of elution data. The method includes setting a preferred target temperature when an external power source is available, when faster sensor response is desired, and when higher resolution data is desired. The method further includes controlling the temperature of gas chromatography (GC) columns within a GC sensor to the target temperature.

Abstract: A method and apparatus for two-dimensional gas chromatography (GC), including a valve having first and second positions (P1, and P2), and first through fourth sample flow paths (FP1-FP4). In P1, a first gas sample is collected from a first dimension GC column via FP1, a first pressure source and a first, second dimension GC column are connected via FP2, a second pressure source and a second, second dimension GC column are connected via FP3, and FP4 is disconnected. In P2, the first sample in FP1 is introduced to the second, second dimension GC column via FP1, with aid of the second pressure source, a second gas sample is collected from the first dimension GC column via FP2, the first pressure source and the first, second dimension GC column via FP4 are connected, and FP3 is disconnected.

Abstract: Certain embodiments described herein are directed to chromatography systems that include a microfluidic device. The microfluidic device can be fluidically coupled to a switching valve to provide for selective control of fluid flow in the chromatography system. In some examples, the microfluidic device may include a charging chamber, a bypass restrictor or other features that can provide for added control of the fluid flow in the system. Methods of using the devices and methods of calculating lengths and diameters to provide a desired flow rate are also described.

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 inlet pressure, determining the 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 drop across the transfer line and calculating the outlet pressure from the measured inlet pressure and the pressure drop.

Abstract: A flammable gas concentration device comprises an adsorption tower filled by an adsorbent for adsorbing a flammable gas; feeding means for feeding a raw gas containing air and a flammable gas to the adsorption tower via a feeding path and discharging an exhaust gas in the raw gas which has not been adsorbed to the adsorbent to an outside of the adsorption tower via a discharge path; collection means for reducing a pressure in the adsorption tower lower than an atmospheric pressure, and desorbing the flammable gas adsorbed by the adsorbent and collecting the flammable gas through a collection path; and control means for sequentially executing a flammable gas adsorption step of feeding the raw gas to the adsorption tower and discharging the exhaust gas from the adsorption tower by the feeding mean, and a flammable gas desorption step of collecting the flammable gas desorbed by the collection means.

Abstract: Systems and methods for performing chromatography separations or analyses are disclosed. The methods are based upon an equilibrium gradient focusing mode in contrast to conventional transient migration-based modes. By matching the migration speed of one or more analyte(s) of interest to the wave speed of a thermal gradient induced to travel along a region in which chromatographic partitioning occurs, significant improvements in detection limits are achieved. In particular, a temperature gradient focusing strategy is described in which analyte(s) of interest are circulated around a continuous chromatography system in order to focus the analyte(s). Also described are various devices and systems that can be used in the methods described herein.

Abstract: A multicapillary bundle for use in a gas chromatograph. Each of the capillaries in the bundle is formed using a coating solution containing a stationary phase and a solvent. The capillaries are coated with stationary phase by reducing pressure at a vacuum end of the capillary and creating a moving interface between the coating solution and a film of stationary phase deposited on each of the capillaries. The reducing pressure at the vacuum end of the capillary and the temperature of the capillary are controlled to maintain motion of the moving interface away from the vacuum end of the capillary. Maintained movement of the interface prevents recoating of the stationary phase. A heating wire and capillaries are embedded in a thermally conductive polymer to create a highly responsive method of heating the multicapillary column. An electronic control device controls the feedback temperature of the multicapillary column using the heating wire.

Abstract: The invention relates to a medical device for producing oxygen, wherein the device comprises means for providing first conditions, and means for changing said first conditions to second conditions, the device being configured to during a charging phase extract oxygen from air by, under said first conditions, bringing said air (A) into contact with an agent (SfF) constituted by a reversibly oxygen-fixating agent, i.e. an oxygen selective material, such that the oxygen of the air is adsorbed by said agent, and to remove nitrogen under said first conditions, and configured to during a discharging phase release the oxygen from the agent by means of changing said first conditions to said second conditions. The invention also relates to a method for producing oxygen for individual medical purposes.

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: An oxygen separator for separating oxygen from ambient air utilizing a vacuum swing adsorption process has a mass of less than 2.3 kg. A carrier is mountable on a person to support the oxygen separator for ambulatory use.

Abstract: Disclosed is a gas chromatograph, which comprises a column oven which has a ventilation door disposed in an upper portion thereof and a hydrogen gas sensor installed in an upper region of an internal space thereof. Based on a detection signal from the hydrogen gas sensor, a control section determines a concentration of hydrogen gas contained in a gas within the column oven. If the concentration is equal to or greater than a given threshold value, the control section operates to open the ventilation door while cutting off current to be supplied to a heater, and closing a valve to stop supply of hydrogen gas. Thus, in the event of leakage of hydrogen gas, hydrogen gas accumulated within the column oven can be quickly released outside the column oven to avoid a risk of inflaming.

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: The aim of the invention is to optimize the analysis of substances separated by gas chromatography with a gas chromatograph, comprising a separating device and a mass spectrometer situated down there from. To this end, a detector that detects the separated substances in a nondestructive manner is placed in-line between the output of the separating device and a controllable inlet valve of the mass spectrometer. An evaluating device situated down from the detector evaluates the detector signals and, based on the evaluation, controls the inlet valve for introducing predeterminable substances into the mass spectrometer.

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: The present invention discloses a gas chromatograph assembly. In one implementation, the assembly includes a sample injector and a guard column assembly. The guard column assembly includes a guard column connected to and downstream of the sample injector; a jacket with low thermal mass surrounding the guard column; a temperature controlled heater connected to the jacket to control the temperature of the jacket and thereby the temperature of the guard column; and an insulating housing surrounding the jacket. An analytical column is connected to and downstream of the guard column.

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 inlet pressure, determining the 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 drop across the transfer line and calculating the outlet pressure from the measured inlet pressure and the pressure drop.

Abstract: An apparatus and a method for separating a specified gas from a gas to be treated containing the specified gas comprising at least one ingredient, which comprises allowing the gas to be treated to flow through a column without the use of another gas for transferring the gas to be treated, while keeping the inside of the column packed with a packing material at a reduced pressure. The above apparatus and method can be suitably used for separating a specified gas having a high purity at a low cost.

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 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.