Abstract: A sample preparation apparatus for an elemental analysis system comprising a sample combustion and/or reduction and/or pyrolysis arrangement for receiving a sample of material to be analysed, and producing therefrom a sample gas flow containing atoms, molecules and/or compounds; a gas chromatography (GC) column into which the sample gas flow is directed; a heater for heating at least a part of the GC column; and a controller for controlling the heater. The controller is configured to control the heater so as to increase the temperature of at least the part of the GC column whilst the sample gas flow in the GC column elutes.

Abstract: A sample preparation apparatus for an elemental analysis system comprising a sample combustion and/or reduction and/or pyrolysis arrangement for receiving a sample of material to be analysed, and producing therefrom a sample gas flow containing atoms, molecules and/or compounds; a gas chromatography (GC) column into which the sample gas flow is directed; a heater for heating at least a part of the GC column; and a controller for controlling the heater. The controller is configured to control the heater so as to increase the temperature of at least the part of the GC column whilst the sample gas flow in the GC column elutes.

Abstract: A gas inlet system for introducing gas into an isotope ratio analyzer, the gas inlet system including a reference system comprising: a first supply of a reference gas having a first known isotope ratio; a supply of a carrier gas, wherein the supplies of reference gas and carrier gas are each connected by respective reference and carrier gas lines to a first mixing junction where the reference gas and carrier gas combine; a mixing zone connected downstream of the first mixing junction wherein the combined reference gas and carrier gas mix together; an exit line for transporting the mixed gas from the mixing zone to the isotope ratio analyzer; and an opening on the exit line, wherein the opening is downstream of the mixing zone. Also provided is a method of determining an isotope ratio.

Abstract: A gas transport system includes at least one chemical reactor having at least one inlet and at least one gas outlet and at least one sample introduction unit for delivering the sample into the chemical reactor. The gas transport system at least one carrier gas line fluidly coupled to the chemical reactor inlet for introducing into the chemical reactor carrier gas from a carrier gas source, at least one gas outlet line from the chemical reactor gas outlet, and at least one gas recycling line connected to the gas outlet and/or the gas outlet line by a first gas line junction that is arranged between the chemical reactor and a downstream detection unit on the gas outlet line. The gas transport system is adapted to allow recycling of at least a portion of gas emerging from the chemical reactor outlet back to the chemical reactor via the gas recycling line.

Abstract: A sample preparation apparatus for an elemental analysis system comprising a sample combustion and/or reduction and/or pyrolysis arrangement for receiving a sample of material to be analyzed, and producing therefrom a sample gas flow containing atoms, molecules and/or compounds; a gas chromatography (GC) column into which the sample gas flow is directed; a heater for heating at least a part of the GC column; and a controller for controlling the heater. The controller is configured to control the heater so as to increase the temperature of at least the part of the GC column while the sample gas flow in the GC column elutes.

Abstract: A gas inlet system for introducing gas into an isotope ratio analyzer, the gas inlet system including a reference system comprising: a first supply of a reference gas having a first known isotope ratio; a supply of a carrier gas, wherein the supplies of reference gas and carrier gas are each connected by respective reference and carrier gas lines to a first mixing junction where the reference gas and carrier gas combine; a mixing zone connected downstream of the first mixing junction wherein the combined reference gas and carrier gas mix together; an exit line for transporting the mixed gas from the mixing zone to the isotope ratio analyzer; and an opening on the exit line, wherein the opening is downstream of the mixing zone. Also provided is a method of determining an isotope ratio.

Abstract: A system for concentrating an analyte gas in a gas stream of an analytical system is provided. The system comprises at least one separation device, at least one gas inlet line, at least one detector, at least one gas outlet line, a first split line in connected to the gas inlet line, and a first split valve for controlling gas flow in the first split line. Also provided is a method for concentrating an analyte gas.

Abstract: A sample preparation apparatus for an elemental analysis system comprising a sample combustion and/or reduction and/or pyrolysis arrangement for receiving a sample of material to be analysed, and producing therefrom a sample gas flow containing atoms, molecules and/or compounds; a gas chromatography (GC) column into which the sample gas flow is directed; a heater for heating at least a part of the GC column; and a controller for controlling the heater. The controller is configured to control the heater so as to increase the temperature of at least the part of the GC column whilst the sample gas flow in the GC column elutes.

Abstract: An isotope ratio of a continuous sample is measured in an isotope ratio spectrometer. At least one sample isotope ratio is measured over a measurement time period tns, (n?1) and a sample concentration cns is measured over at least a part of the measurement time period tns. A reference gas concentration cnref for the spectrometer is selected for reference to the sample measured during the measurement time period tns, on the basis of the measured sample concentration cnref. An isotope ratio of the reference gas is measured at the selected reference gas concentration cnref in the spectrometer. The at least one isotope ratio of the sample measured during the measurement time period tns is calibrated using the measured isotope ratio of the reference gas at the corresponding reference gas concentration cnref and a plurality of calibrated isotope ratios and a plurality of sample gas concentration measurements are determined, each being for a different time.

Abstract: A gas inlet system for introducing gas into an isotope ratio analyzer, the gas inlet system including a reference system comprising: a first supply of a reference gas having a first known isotope ratio; a supply of a carrier gas, wherein the supplies of reference gas and carrier gas are each connected by respective reference and carrier gas lines to a first mixing junction where the reference gas and carrier gas combine; a mixing zone connected downstream of the first mixing junction wherein the combined reference gas and carrier gas mix together; an exit line for transporting the mixed gas from the mixing zone to the isotope ratio analyzer; and an opening on the exit line, wherein the opening is downstream of the mixing zone. Also provided is a method of determining an isotope ratio.

Abstract: A gas inlet system for introducing gas into an isotope ratio analyser, the gas inlet system including a reference system comprising: a first supply of a reference gas having a first known isotope ratio; a supply of a carrier gas, wherein the supplies of reference gas and carrier gas are each connected by respective reference and carrier gas lines to a first mixing junction where the reference gas and carrier gas combine; a mixing zone connected downstream of the first mixing junction wherein the combined reference gas and carrier gas mix together; an exit line for transporting the mixed gas from the mixing zone to the isotope ratio analyser; and an opening on the exit line, wherein the opening is downstream of the mixing zone. Also provided is a method of determining an isotope ratio.

Abstract: A gas transport system includes at least one chemical reactor having at least one inlet and at least one gas outlet and at least one sample introduction unit for delivering the sample into the chemical reactor. The gas transport system at least one carrier gas line fluidly coupled to the chemical reactor inlet for introducing into the chemical reactor carrier gas from a carrier gas source, at least one gas outlet line from the chemical reactor gas outlet, and at least one gas recycling line connected to the gas outlet and/or the gas outlet line by a first gas line junction that is arranged between the chemical reactor and a downstream detection unit on the gas outlet line. The gas transport system is adapted to allow recycling of at least a portion of gas emerging from the chemical reactor outlet back to the chemical reactor via the gas recycling line.

Abstract: A system for concentrating an analyte gas in a gas stream of an analytical system is provided. The system comprises at least one separation device, at least one gas inlet line, at least one detector, at least one gas outlet line, a first split line in connected to the gas inlet line, and a first split valve for controlling gas flow in the first split line. Also provided is a method for concentrating an analyte gas.

Abstract: An isotope ratio of a continuous sample is measured in an isotope ratio spectrometer. At least one sample isotope ratio is measured over a measurement time period tns, (n?1) and a sample concentration cns is measured over at least a part of the measurement time period cns. A reference gas concentration cnref for the spectrometer is selected for reference to the sample measured during the measurement time period tns, on the basis of the measured sample concentration cnref. An isotope ratio of the reference gas is measured at the selected reference gas concentration cnref in the spectrometer. The at least one isotope ratio of the sample measured during the measurement time period tnref is calibrated using the measured isotope ratio of the reference gas at the corresponding reference gas concentration cnref and a plurality of calibrated isotope ratios and a plurality of sample gas concentration measurements are determined, each being for a different time.

Abstract: A gas inlet system for introducing gas into an isotope ratio analyser, the gas inlet system including a reference system comprising: a first supply of a reference gas having a first known isotope ratio; a supply of a carrier gas, wherein the supplies of reference gas and carrier gas are each connected by respective reference and carrier gas lines to a first mixing junction where the reference gas and carrier gas combine; a mixing zone connected downstream of the first mixing junction wherein the combined reference gas and carrier gas mix together; an exit line for transporting the mixed gas from the mixing zone to the isotope ratio analyser; and an opening on the exit line, wherein the opening is downstream of the mixing zone. Also provided is a method of determining an isotope ratio.