Abstract: The invention concerns a device for vaporizing injections of samples into a gas chromatography analysis device, comprising a vaporization chamber elongated lengthways and heated, as well as a syringe equipped with a needle, the device being of the type in which the introduction of the sample is carried out without prior vaporization of the sample within the needle, and also foresees at least one stop and vaporization means for the liquid inside the vaporization chamber. To improve the conditions of vaporization and the transfer of the sample, the distance between the free end of the needle and the stated stop and vaporization means for the liquid is greater than 55 mm (FIG. 1).

Abstract: A micro-gas chromatograph column is formed by texturing a channel into a plurality of green-sheet layers, which are then sintered together to form a substantially monolithic structure. A thick-film paste may be added to the channel textured in the green-sheet layers to provide a porous plug sintered in the micro-gas chromatograph column in the substantially monolithic. A thermal conductivity detector is formed in the substantially monolithic structure by depositing a conductive thick-film paste on the surface of one of the green-sheet layers to define a resistor in an exit channel of the micro-gas chromatograph column.

Abstract: A glass-silicon column that can operate in temperature variations between room temperature and about 450° C. The glass-silicon column includes large area glass, such as a thin Corning 7740 boron-silicate glass bonded to a silicon wafer, with an electrode embedded in or mounted on glass of the column, and with a self alignment silicon post/glass hole structure. The glass/silicon components are bonded, for example be anodic bonding. In one embodiment, the column includes two outer layers of silicon each bonded to an inner layer of glass, with an electrode imbedded between the layers of glass, and with at least one self alignment hole and post arrangement. The electrode functions as a column heater, and one glass/silicon component is provided with a number of flow channels adjacent the bonded surfaces.

Abstract: A high-sensitivity, separation microcolumn assembly for a microgas chromatograph and the like is provided. The assembly has an ultra-low mass complete with integrated heaters. The assembly uses multiple zones for temperature control, and microstructures that permit very rapid heating and cooling of the microcolumn.

Abstract: A temperature programmable microfabricated gas chromatography column enables more efficient chemical separation of chemical analytes in a gas mixture by the integration of a resistive heating element and temperature sensing on the microfabricated column. Additionally, means are provided to thermally isolate the heated column from their surroundings. The small heat capacity and thermal isolation of the microfabricated column improves the thermal time response and power consumption, both important factors for portable microanalytical systems.

Abstract: A new class of miniaturized gas chromatographic columns has been invented. These chromatographic columns are formed using conventional micromachining techniques, and allow packed columns having lengths on the order of a meter to be fabricated with a footprint on the order of a square centimeter.

Abstract: The invention relates to a process and to an apparatus for providing gas for isotopic ratio analysis. According to the invention, a gas is generated from an eluate of a liquid chromatograph (LC). Subsequently, the gas is separated from the eluate. Finally, the gas is fed to an instrument (IRMS) for isotopic ratio analysis.

Abstract: An apparatus for collecting and detecting chemicals contained in a fluid includes a sorbent element, at least one chemical sensor, a first pump for pumping fluid through the sorbent element and a second pump for pumping fluid to the chemical sensor. The sorbent element contains a sorbent material and a heating element. The first pump pumps fluid into the sorbent element thereby collecting the chemicals on the sorbent material. The heating element provides heat to the sorbent element to desorb the chemicals from the sorbent material. The chemicals desorbed from the sorbent material are then pumped out of the sorbent element and to the chemical sensor. The sorbent material may have a cavity therein with the heating element located in that cavity. Alternatively, the heating element may be interposed between the enclosure and the sorbent material.

Abstract: A two-dimensional gas chromatograph with a primary column (14) and dual secondary columns (26, 28) is described. Flow rates in the primary column are less than those in the secondary columns due to an accumulation valve (16). Typically the ratio of second and third column flow capacities combined to primary column flow capacities between about 10 to 1 and 30 to 1. Volatile organic compounds are detected in environmental samples of air water, soil and in body fluids of animals and humans.

Abstract: This invention relates to a modulator for use in gas chromatographic analysis, adopted for alternatively trapping and releasing fractions of solutes in a length of a capillary column within a chromatographic oven, characterized in that it comprises at least one nozzle placed to spray at least one jet in at least one corresponding place along said capillary column length, said nozzle(s) being connected each to a source of liquid CO2 via a related valve, and means for alternatively opening said valve(s) for a predetermined time, to cause a jet of liquid CO2 to impinge for said predetermined time on said column place and to leave the oven atmosphere to heat said column place after said predetermined time. The modulator can be used in a conventional GC system or in a two dimensional GC system, for modulating the analytes fed to the second capillary column.

Abstract: A thermal conductivity detector includes not only a thermal conductivity detector cell disposed so as to be heated by heat transmitted from a first heater block and a column connector connected to the detector cell and to a column of a chromatograph but also a second heater block for heating the column connector. The heaters for individually heating these two heater blocks are controlled simultaneously and in synchronism by a single temperature controller according to the temperature of the first heater block for heating the detector cell.

Abstract: A method for measuring anions by suppressor-system or non-suppressor-system ion chromatography includes measuring halogen oxide ions with a column for ion chromatography, which is packed with an alkali-resistant anion exchanger including porous polymer particles, in combination with one or more eluents, the porous polymer particles including an alkali-resistant polymer substrate having bonded thereto through a spacer a nitrogen-containing heterocyclic group having a quaternary ammonium structure.

Abstract: Laminates having microfluidic structures disposed between sheets of the laminate are provided. The microfluidic structures are raised on a sheet of laminate, typically by printing the structure on the sheet. Printing methods include Serigraph, ink-jet, intaligo, offset printing and thermal laser printing.

Abstract: A sample inlet liner includes a novel matrix that serves to retain an injected sample. The preferred inert matrix is polytetrafluoroethylene (PTFE) that serves to retain an injected sample and is provided in lieu of a conventional packing material. The contemplated inert matrix may be selected from a range of configurations of PTFE so as to provide a supporting material capable of retaining an ample quantity of injected sample in the sample inlet liner. The contemplated matrix nonetheless provides a tortuous path for the retained quantity of injected sample so as to facilitate known injection techniques such as split/splitless injection and large volume injections.

Abstract: The present disclosure relates to a gas chromatograph having a plurality of layers or channels. The chromatograph typically comprises an inlet that receives a sample to be analyzed, a column disposed in each of the plurality of chromatograph layers, each column being in fluid communication with and downstream from the inlet and having a stationary phase coating its inner surfaces, and a detector in fluid communication with and downstream from at least one of the columns. In a preferred arrangement, the chromatograph includes a pre-column disposed in each of the chromatograph layers upstream of the columns, each pre-column being in fluid communication with the inlet and having a stationary phase coating its inner surfaces.

Abstract: A thermostat array including an array of two or more capillary columns (10) or two or more channels in a microfabricated device is disclosed. A heat conductive material (12) surrounded each individual column or channel in array, each individual column or channel being thermally insulated from every other individual column or channel. One or more independently controlled heating or cooling elements (14) is positioned adjacent to individual columns or channels within the heat conductive material, each heating or cooling element being connected to a source of heating or cooling, and one or more independently controlled temperature sensing elements (16) is positioned adjacent to the individual columns or channels within the heat conductive material. Each temperature sensing element is connected to a temperature controller.

Abstract: A device for analyzing organic compounds, particularly in aqueous and gaseous samples, constituted by a duct which is supplied in input by a gas whose pressure can be controlled by means of a regulator connected to a capillary column which is connected in output to a detector for the organic compounds; an adsorbent polymer immersed in a container is interposed between a first portion and a second portion of the capillary column, and the device comprises, between the second portion and a third portion, means for concentrating the organic compounds; the container contains an aqueous or gaseous sample which interacts with the adsorbent polymer adapted to extract the organic compounds conveyed by the gas in passing through the adsorbent polymer toward the concentration means in order to be measured by the detector.

Abstract: A gas chromatograph has a pressure sensor measuring a pressure in a sample introduction part, a flow control valve controlling carrier gas flow rate, a flow sensor measuring a flow rate of the carrier gas, a split flow path exhausting part of a carrier gas and sample from the introduction part, an exhaust valve placed in the sprit flow path, and a monitor screen. The controller controls the flow control valve to flow the carrier gas at the designated flow rate into the introduction part, reads an output of the pressure sensor after making the exhaust valve fully open, calculates a flow path resistance of the filter by using an output of the pressure sensor and a flow path resistance of the chromatographic column, and controls the monitor screen to display an indication for exchanging the filter when the calculated resistance reaches the preset value corresponding to a state in which the filter is stuffed.

Abstract: A flow of a carrier gas through a column is provided. A sample is provided in the column, and a temperature of a longitudinally short portion of the column is raised to a predetermined controlled high temperature at which volatile substances are released from the sample packing and are carried by the carrier gas. The column is cooled on each side of the short portion to a low temperature at which the volatile substances condense or adsorb on the column packing. By continuously moving the heated short portion from an inlet end to an outlet end of the packing in a direction of carrier gas flow the volatile substances selected by the controlled high temperature are released. Four particularly useful and advantageous applications can be identified for the invention. Firstly, it provides an improved gas chromatograph (GC) injector. Secondly, it provides an improved thermal separator or extractor.

Abstract: The present invention relates to a device in gas flow cells for the analysis of chemical substances by spectrophotometry. The gas flow cell has two longitudinal ducts, which are connected by a connection so that a first flow is permitted though the ducts and the connection. The first duct in the direction of flow has a separation column and the second duct is a light guide. The invention is characterized in that in the connection there is a coupling, which is connected with the outlet from an external separation unit. The connection is designed to receive a second flow comprising the substances separated in the external separation unit together with a first carrier gas, so that the second flow is added to the first flow in the connection. The device is designed to function in either of two operating positions, where in the first position the device functions in the conventional manner and where in the second position the first flow comprises the second carrier gas and the second flow is connected up.

Abstract: A gas chromatographic device has an inlet system, a column and a pressure reducing means combined and assembled in such a series arrangement that provides adequate system performance with shorter wide bore column length and shorter sample analysis times needed during a peak integration and evaluation process performed by a connected mass spectrometer system. Pressure reducing means may be integral part of the inlet system or the column when positioned between the inlet system and the column. Pressure reducing means preferably positioned before the column and being capable of reducing the pressure prevailing at the inlet of said pressure reducing means to a column outlet pressure which is essentially vacuum. Preferably, the inlet pressure of the device is in a range between 10 kPa and 1000 kPa and the absolute pressure prevailing at the outlet of said pressure reducing means is in a range between 0.00001 kPa and 50 kPa.

Abstract: This invention provides a reduced power consumption gas chromatograph system (10) which includes a capillary gas chromatograph column member (12) which contains a chemical sample to be analyzed. The gas chromatograph system further includes a heating mechanism (16) which extends throughout the length of the capillary gas chromatograph column member (12) and surrounds both the member (12) and a temperature sensing mechanism (14) which is mounted adjacent to the column member (12). The temperature sensing mechanism (14), the heating mechanism (16) and the column member (12) form a chromatograph column assembly (20) which includes a coiled section (28) where the components are tightly packed with respect to each other and allows for a reduced power consumption for temperature programming miniature gas chromatography column assemblies.

Abstract: This invention provides a reduced power consumption gas chromatograph system (10) which includes a capillary gas chromatograph column member (12) which contains a chemical sample to be analyzed. The gas chromatograph system further includes a heating mechanism (16) which extends throughout the length of the capillary gas chromatograph column member (12) and surrounds both the member (12) and a temperature sensing mechanism (14) which is mounted adjacent to the column member (12). The temperature sensing mechanism (14), the heating mechanism (16) and the column member (12) form a chromatograph column assembly (20) which includes a coiled section (28) where the components are tightly packed with respect to each other and allows for a reduced power consumption for temperature programming miniature gas chromatography column assemblies.

Abstract: An electrically insulated gas chromatograph assembly suitable for high temperature operation in a miniaturized, low power, low thermal mass gas chromatograph instrument is provided. The gas chromatograph (GC) assembly includes a metal capillary GC column (152) having a ceramic fiber insulating layer (156) wrapped about an outer surface thereof. Heater wire (160) is similarly wrapped with a ceramic fiber electrical insulating layer (158). Resistive temperature device (RTD) wire (154) is positioned contiguous an outer surface of insulating layer (156). The composite assembly including insulated capillary GC column (152), insulated heater wire (160), and RTD wire (154), are bound together by applying thereto a spiral wrapped ceramic fiber insulating layer (162).