A method of determining the inertness of a material regarding the formation of heavy by-products during the reaction of propylene to acrolein and acrylic acid.

To increase the difference between the thermal conductivity of the carrier gas and the thermal conductivity of each component of the sample gas. The analysis method is an analysis method that performs analysis using a gas chromatograph including a thermal conductivity detector. The analysis method includes introducing a carrier gas and a sample gas into a separation column, introducing the sample gas separated in the separation column into a gas introduction chamber including an element having an electrical characteristic changed by temperature, detecting a change in the electrical characteristic of the element due to the sample gas being introduced, and switching the carrier gas from a first carrier gas to a second carrier gas that is a different type from the first carrier gas, while a component of the sample gas is passing through the separation column.

To increase the difference between the thermal conductivity of the carrier gas and the thermal conductivity of each component of the sample gas. The analysis method is an analysis method that performs analysis using a gas chromatograph including a thermal conductivity detector. The analysis method includes introducing a carrier gas and a sample gas into a separation column, introducing the sample gas separated in the separation column into a gas introduction chamber including an element having an electrical characteristic changed by temperature, detecting a change in the electrical characteristic of the element due to the sample gas being introduced, and switching the carrier gas from a first carrier gas to a second carrier gas that is a different type from the first carrier gas, while a component of the sample gas is passing through the separation column.

A system and method of determining levels of contaminants in a base gas. A gas chromatography column is used as part of a cold trap. A sample of a base gas is fed through the gas chromatography column. Due to the temperature of the gas chromatography column, some of the contaminants concentrate. A purified carrier gas is directed through the reinforced tube assembly after contaminants have collected. The gas chromatography column is heated to a second temperature that releases at least some of the concentrated contaminants. The contaminants mix with the purified carrier gas to create a contaminated carrier gas. The contaminated carrier gas is directed to one or more testing units that analyze the contaminated carrier gas to quantify the contaminants.

A system and method of determining levels of contaminants in a base gas. A gas chromatography column is used as part of a cold trap. A sample of a base gas is fed through the gas chromatography column. Due to the temperature of the gas chromatography column, some of the contaminants concentrate. A purified carrier gas is directed through the reinforced tube assembly after contaminants have collected. The gas chromatography column is heated to a second temperature that releases at least some of the concentrated contaminants. The contaminants mix with the purified carrier gas to create a contaminated carrier gas. The contaminated carrier gas is directed to one or more testing units that analyze the contaminated carrier gas to quantify the contaminants.

A detector for gas chromatography includes a manifold, a first bridge circuit, and a second bridge circuit. A first analysis flow path, a first reference flow path, a second analysis flow path, and a second reference flow path are formed in the manifold. The first bridge circuit is configured to be capable of detecting a predetermined component in a first analysis gas using the first analysis resistive body and the first reference resistive body. The second bridge circuit is configured to be capable of detecting a predetermined component in a second analysis gas using the second analysis resistive body and the second reference resistive body. The distance between the first analysis resistive body and the second reference resistive body is less than the distance between the first analysis resistive body and the second analysis resistive body.

A detector for gas chromatography includes a manifold, a first bridge circuit, and a second bridge circuit. A first analysis flow path, a first reference flow path, a second analysis flow path, and a second reference flow path are formed in the manifold. The first bridge circuit is configured to be capable of detecting a predetermined component in a first analysis gas using the first analysis resistive body and the first reference resistive body. The second bridge circuit is configured to be capable of detecting a predetermined component in a second analysis gas using the second analysis resistive body and the second reference resistive body. The distance between the first analysis resistive body and the second reference resistive body is less than the distance between the first analysis resistive body and the second analysis resistive body.

Provided is a thermal conductivity detector including a detection channel through which a gas to be measured flows as a fluid, a heat conducting part that includes at least a filament provided at a position in the detection channel at which the filament is in direct contact with the fluid flowing through the detection channel, the filament being folded at least once in a direction substantially parallel to a flow direction of the fluid flowing through the detection channel, and that conducts heat via the fluid flowing through the detection channel, and a detection circuit that detects an electric signal in accordance with a change in current or voltage of the filament. The filament is folded by being holed on a folding pin provided substantially perpendicular to the flow direction in the detection channel, and the folding pin has a position shift prevention structure for preventing a fold of the filament hooked on the folding pin from shifting in a longitudinal direction of the folding pin.

Provided is a thermal conductivity detector including a detection channel through which a gas to be measured flows as a fluid, a heat conducting part that includes at least a filament provided at a position in the detection channel at which the filament is in direct contact with the fluid flowing through the detection channel, the filament being folded at least once in a direction substantially parallel to a flow direction of the fluid flowing through the detection channel, and that conducts heat via the fluid flowing through the detection channel, and a detection circuit that detects an electric signal in accordance with a change in current or voltage of the filament. The filament is folded by being holed on a folding pin provided substantially perpendicular to the flow direction in the detection channel, and the folding pin has a position shift prevention structure for preventing a fold of the filament hooked on the folding pin from shifting in a longitudinal direction of the folding pin.

A method for surface characterization of a porous solid or powder sample using flowing gas includes a controller that controls mass flow of a carrier gas and an adsorptive gas to form a mixture having a target concentration of the adsorptive gas over the sample, determining adsorptive gas concentration based on signals from a detector disposed downstream of the sample, automatically repeating the controlling and determining steps for a plurality of different target concentrations, and generating an isotherm for the sample based on the adsorptive gas concentration for the plurality of different target concentrations. The method may include immersing the sample in liquid nitrogen to cool the sample for all, or at least a portion of each of the different target concentrations. The target concentrations may vary from less than 5% to greater than 95%, and may vary in a stepwise manner.