A liquid chromatograph includes: an analysis column; a sample loop that temporarily contains a mixed liquid of a sample and a mixture solvent; and a passage switch valve capable of switching a passage between a load position where the mixed liquid is temporarily held in the sample loop and an injection position where the mixed liquid held in the sample loop is sent to the analysis column. In the liquid chromatograph, a specific passage is formed in each of the load position and the injection position.

A liquid chromatograph includes: an analysis column; a sample loop that temporarily contains a mixed liquid of a sample and a mixture solvent; and a passage switch valve capable of switching a passage between a load position where the mixed liquid is temporarily held in the sample loop and an injection position where the mixed liquid held in the sample loop is sent to the analysis column. In the liquid chromatograph, a specific passage is formed in each of the load position and the injection position.

The present disclosure provides an automatic separation apparatus for four fractions of heavy oil and a separation method thereof, wherein the apparatus includes a solvent reservoir tank (1), a separation unit for four fractions of heavy oil (100) and a receiving apparatus (9). The separation unit for four fractions of heavy oil (100) includes: a filter disc (4) having one end in communication with the solvent reservoir tank (1), and the other end in communication with an inlet of a pre-column flow path switching valve (5); a chromatographic column (6) having an inlet in communication with an outlet of the pre-column flow path switching valve (5), and an outlet in communication with an inlet of a post-column flow path switching valve (8). The receiving apparatus is in communication with an outlet of the post-column flow path switching valve (8).

The present disclosure provides an automatic separation apparatus for four fractions of heavy oil and a separation method thereof, wherein the apparatus includes a solvent reservoir tank (1), a separation unit for four fractions of heavy oil (100) and a receiving apparatus (9). The separation unit for four fractions of heavy oil (100) includes: a filter disc (4) having one end in communication with the solvent reservoir tank (1), and the other end in communication with an inlet of a pre-column flow path switching valve (5); a chromatographic column (6) having an inlet in communication with an outlet of the pre-column flow path switching valve (5), and an outlet in communication with an inlet of a post-column flow path switching valve (8). The receiving apparatus is in communication with an outlet of the post-column flow path switching valve (8).

A method for determining a state of a fluidic system can include measuring back pressures in the fluidic system at different times and determining a state of the fluidic system. The determination is based on at least the measured back pressures and on additional status information indicative of at least one status of the fluidic system at at least one of the different times.

A method for determining a state of a fluidic system can include measuring back pressures in the fluidic system at different times and determining a state of the fluidic system. The determination is based on at least the measured back pressures and on additional status information indicative of at least one status of the fluidic system at at least one of the different times.

Method for adapting the concentration of a sample gas in a gas mixture to be analysed by a gas chromatograph assembly (10), the gas chromatograph assembly (10) comprising a sample gas inlet (20) for introducing a sample gas to be analysed, a secondary gas inlet (40), a gas chromatograph infrared sensor (12), a gas chromatograph column (26), and a gas chromatograph bypass (28) parallel to the column (26), characterized by a) introducing an amount of sample gas through the sample gas inlet (20), b) introducing an amount of secondary gas through the secondary gas inlet (40), c) mixing the sample gas and the secondary gas to a gas mixture and conducting the gas mixture via the gas chromatograph bypass (28), d) circulating the gas mixture in a gas conducting loop (52) comprising the gas chromatograph bypass (28), the gas chromatograph infrared sensor (12) and not comprising the gas chromatograph column (26), e) analysing the gas mixture thus obtained by means of gas chromatography employing the gas chromatograph column (26) and the gas chromatograph infrared sensor (12).

Method for adapting the concentration of a sample gas in a gas mixture to be analysed by a gas chromatograph assembly (10), the gas chromatograph assembly (10) comprising a sample gas inlet (20) for introducing a sample gas to be analysed, a secondary gas inlet (40), a gas chromatograph infrared sensor (12), a gas chromatograph column (26), and a gas chromatograph bypass (28) parallel to the column (26), characterized by a) introducing an amount of sample gas through the sample gas inlet (20), b) introducing an amount of secondary gas through the secondary gas inlet (40), c) mixing the sample gas and the secondary gas to a gas mixture and conducting the gas mixture via the gas chromatograph bypass (28), d) circulating the gas mixture in a gas conducting loop (52) comprising the gas chromatograph bypass (28), the gas chromatograph infrared sensor (12) and not comprising the gas chromatograph column (26), e) analysing the gas mixture thus obtained by means of gas chromatography employing the gas chromatograph column (26) and the gas chromatograph infrared sensor (12).

Provided is a gas chromatograph capable of efficiency circulating air in a column oven. The gas chromatograph is provided with a column oven, a heater, a fan, and a cylindrical member. The column oven accommodates a column. The heater heats the inside of the column oven. The fan has a blade that rotates about a rotation axis in the column oven, and sends air toward the column provided in the axial direction that is a direction along the rotation axis. The cylindrical member is arranged to accommodate at least a part of the fan in a state of being spaced apart from the column in the axial direction and surrounding an outer periphery of the fan along a rotational direction of the blade.

Provided is a gas chromatograph capable of efficiency circulating air in a column oven. The gas chromatograph is provided with a column oven, a heater, a fan, and a cylindrical member. The column oven accommodates a column. The heater heats the inside of the column oven. The fan has a blade that rotates about a rotation axis in the column oven, and sends air toward the column provided in the axial direction that is a direction along the rotation axis. The cylindrical member is arranged to accommodate at least a part of the fan in a state of being spaced apart from the column in the axial direction and surrounding an outer periphery of the fan along a rotational direction of the blade.