A hybrid trap including a replaceable open-tubular capillary trap followed by a packed trap is used to collect, preconcentrate, and recover a sample, such as VOCs and SVOCs found in air. The capillary stage prevents losses and carryover of the heavy fraction and can also collect the particles in air that contain the heavier SVOCs, also preventing them from reaching the packed stage. The packed stage traps lighter organic compounds that are not as prone to carryover due to channeling. The capillary and packed traps together provide quantitative recovery of compounds boiling from as low as 50 C. to as high as 600 C. The sample can be directly desorbed onto the GC column, which avoids losses and contamination caused by other approaches that thermally desorb samples through transfer lines and rotary valves more remote to the GC oven.

A water removal method for gas concentration sampling, and a sampling method and device. The water removal method comprises: removing water from a sample gas by means of a first cold trap tube filled with a hydrophilic material, and then concentrating the sample gas by means of a concentration cold trap tube; then by means of a carrier gas, conveying components desorbed by the first cold trap tube under a heating state to a second cold trap tube that is in a cooled state and that is filled with a hydrophobic organic adsorbent material, and adsorbing organic substances in the components desorbed by the first cold trap tube: by means of the carrier gas, bringing the moisture desorbed by the first cold trap tube out of the second cold trap tube, and then by means of the carrier gas, conveying residual components desorbed by the first cold trap tube and the second cold trap tube under the heating state to the concentration cold trap tube for concentration.

Techniques disclosed herein can be used to perform a rapid, splitless injection of a sample including SVOCs and VOCs. In some embodiments, a system includes two focusing traps combined in series, one inside of a GC oven and one in a separate oven to concentrate the SVOCs inside of the GC oven and concentrate the VOCs outside of the GC oven. Heating the VOC focusing trap and reversing the flow through both focusers allows splitless injection of compounds boiling from as low as ?100? C. to as high as 600? C. in a single analysis, with a narrow injection bandwidth to optimize both sensitivity and the resolving power of the analyzer.

A system for preparing a test sample includes a vial holder, a needle trap connected to the vial holder, and a sample preparation station. The vial holder includes a vial chamber configured to hold a vial, a purge gas needle, and a needle trap heater. The needle trap includes a needle with the needle trap heater surrounding a distal end portion of the needle. A packing bed is disposed in the needle at the distal end portion. The sample preparation station includes a housing and a vial heater assembly including a vial heater and defining a cavity. The vial holder is configured to be received in the cavity in an installed position with the vial heater surrounding at least a portion of the vial.

A cooling unit (cryo-focus unit) cools breath introduced into a carrier gas from a sample introduction unit, to trap volatile components in the breath into a column. A heater heats the volatile components trapped in the column to desorb the volatile components. Amass spectrometry (MS) section detects the volatile components desorbed by the heater and separated in a process of passing through the column. The breath introduced into the carrier gas from the sample introduction unit is cooled by the cooling unit, whereby more volatile components in the breath are trapped, and those volatile components can be desorbed, and can be detected by the MS section.

A sample analysis method includes directing a sample that contains one or more SVOC components to a GC column to temporally separate components present in the sample. Output gas from the GC column is expanded into a sample cell. The sample cell is held at a temperature and pressure that are lower than the temperature and pressure at an outlet of the GC column. The volume of the sample cell is sufficiently large for maintaining the one or more SVOC components in a gaseous phase. Infrared spectra of the components in the sample cell are obtained using a Fourier transform infrared spectrometry system.

A thermal desorption tube collection system uses a thermoelectric cooler to collect and concentrate gas samples. In some modes, the operation of the cooler is reversed to flow the concentrated sample directly into a separator such as a gas chromatography system. Components resolved in time by a thermal desorption separator accumulate in a sample cell and are analyzed by electromagnetic radiation-based spectroscopic techniques. Also presented are methods for analyzing biogas samples.

The present disclosure is directed to methods and systems for detecting a chemical substance. The methods and systems include using gas-solid phase chemistry to chemically and/or physically modify a substance of interest so that the substance can be vaporized and detected through an analysis of the substance.

A method and system for detecting siloxanes using thermal desorption tubes and FTIR spectrometers with intervening gas chromatography systems.

A method and system for sample analysis involve a temporally-resolving separation of sample components. In the method, solvent vapors are condensed prior to entering a temporally-resolving separator, a GC column, for example, and solvent-depleted vapors are directed to the separator where constituents are resolved in time. A system for analyzing a sample comprises an injection port, a temporally-resolving separator (e.g., a GC column) and a conduit connecting the two. The injection port is at a temperature sufficiently high to vaporize the solvent and analytes present in a sample. The conduit is configured and/or operated to condense the solvent, while maintaining the analytes in the vapor phase.