An ion chromatography (IC) suppressor includes a first clamping plate, an intermediate plate, a second clamping plate, a first ion exchange membrane, a second ion exchange membrane, a first electrode and a second electrode. The first clamping plate, the intermediate plate and the second clamping plate are tightly buckled in sequence to compact the first ion exchange membrane between the first clamping plate and the intermediate plate and compact the second ion exchange membrane between the intermediate plate and the second clamping plate. Resin particles are filled between the two ion exchange membranes. An eluent inlet and an eluent outlet are provided respectively at two ends of the intermediate plate, and an accommodating groove is formed at each of a tail end of the eluent inlet and a head end of the eluent outlet. The first clamping plate and the second clamping plate are provided with a sealing lip, respectively.

An ion chromatography (IC) suppressor includes a first clamping plate, an intermediate plate, a second clamping plate, a first ion exchange membrane, a second ion exchange membrane, a first electrode and a second electrode. The first clamping plate, the intermediate plate and the second clamping plate are tightly buckled in sequence to compact the first ion exchange membrane between the first clamping plate and the intermediate plate and compact the second ion exchange membrane between the intermediate plate and the second clamping plate. Resin particles are filled between the two ion exchange membranes. An eluent inlet and an eluent outlet are provided respectively at two ends of the intermediate plate, and an accommodating groove is formed at each of a tail end of the eluent inlet and a head end of the eluent outlet. The first clamping plate and the second clamping plate are provided with a sealing lip, respectively.

A multi-dimensional liquid chromatography system includes first and second liquid chromatography systems. The first system is configured for providing a first chromatographic separation of a sample fluid comprised in a first mobile phase and to provide a first effluent including at least a portion of the separated sample fluid. The second system is configured for providing a second chromatographic separation of at least a portion of the first effluent comprised in a second mobile phase. A control unit is configured to operate the first liquid chromatography system by maintaining a first flow rate of the first mobile phase substantially constant during the first chromatographic separation, and to operate the second liquid chromatography system during the second chromatographic separation according to a control value different from the second flow rate, so that a variation in the control value can lead to a variation in the second flow rate.

A multi-dimensional liquid chromatography system includes first and second liquid chromatography systems. The first system is configured for providing a first chromatographic separation of a sample fluid comprised in a first mobile phase and to provide a first effluent including at least a portion of the separated sample fluid. The second system is configured for providing a second chromatographic separation of at least a portion of the first effluent comprised in a second mobile phase. A control unit is configured to operate the first liquid chromatography system by maintaining a first flow rate of the first mobile phase substantially constant during the first chromatographic separation, and to operate the second liquid chromatography system during the second chromatographic separation according to a control value different from the second flow rate, so that a variation in the control value can lead to a variation in the second flow rate.

A method of analyzing a polymer resin comprising: providing a polymer resin sample having two or more polymer components; subjecting the sample to aTREF analysis to yield aTREF elution trace by contacting the sample with aTREF solvent to form sample solution; introducing sample solution into aTREF column and allowing elution of polymer components at different elution rates along the column; eluting from the aTREF column an aTREF eluent comprising the polymer components eluting at different rates; and subjecting the aTREF eluent to IR detection to yield the aTREF elution trace; identifying the components of the sample to yield identified components by comparing the elution trace with an identification library that comprises a plurality of known polymer aTREF elution traces correlated with known polymer components characterized by identifying parameters (density, SCB, crystallization temperature, MI, HLMI, MWD); and quantifying each of the identified components to yield quantified polymer components via chemometric analysis.

A method of analyzing a polymer resin comprising: providing a polymer resin sample having two or more polymer components; subjecting the sample to aTREF analysis to yield aTREF elution trace by contacting the sample with aTREF solvent to form sample solution; introducing sample solution into aTREF column and allowing elution of polymer components at different elution rates along the column; eluting from the aTREF column an aTREF eluent comprising the polymer components eluting at different rates; and subjecting the aTREF eluent to IR detection to yield the aTREF elution trace; identifying the components of the sample to yield identified components by comparing the elution trace with an identification library that comprises a plurality of known polymer aTREF elution traces correlated with known polymer components characterized by identifying parameters (density, SCB, crystallization temperature, MI, HLMI, MWD); and quantifying each of the identified components to yield quantified polymer components via chemometric analysis.

A tandem mass spectrometer may be operative to receive sample ions and to monitor a MS scan for a sentinel ion. Upon detection of the sentinel ion in MS1, the mass spectrometer switches to a group of at least one MS/MS scan associated with the sentinel ion to fragment incoming sample ions and to mass analyze resulting product ions of the fragmentation.

A tandem mass spectrometer may be operative to receive sample ions and to monitor a MS scan for a sentinel ion. Upon detection of the sentinel ion in MS1, the mass spectrometer switches to a group of at least one MS/MS scan associated with the sentinel ion to fragment incoming sample ions and to mass analyze resulting product ions of the fragmentation.

In accordance with embodiments of the present invention, a terpene-rich sample is prepared for terpene analysis using liquid chromatography via an extraction method that takes little time, uses minimal external equipment, and permits direct injection of extracted terpenes into a liquid chromatography instrument for analysis. An embodiment of the invention involves preparing a terpene-containing sample for analysis by liquid chromatography by liquid extraction; heating the liquid extract in a vial that contains a filter medium or solvent; collecting the terpenes in the medium by the vapor pressure forced through the filter from heating; and eluting the collected terpenes into a vial or directly into a chromatography injector.

In accordance with embodiments of the present invention, a terpene-rich sample is prepared for terpene analysis using liquid chromatography via an extraction method that takes little time, uses minimal external equipment, and permits direct injection of extracted terpenes into a liquid chromatography instrument for analysis. An embodiment of the invention involves preparing a terpene-containing sample for analysis by liquid chromatography by liquid extraction; heating the liquid extract in a vial that contains a filter medium or solvent; collecting the terpenes in the medium by the vapor pressure forced through the filter from heating; and eluting the collected terpenes into a vial or directly into a chromatography injector.