Abstract: A two-dimensional chromatogram creator creates a two-dimensional chromatogram based on data obtained for each of two samples. A chromatogram difference calculator creates a two-dimensional differential chromatogram showing the intensity difference between the two two-dimensional chromatograms. A blob detector detects blobs on each chromatogram. A matching-blob extractor compares the blobs located on the differential chromatogram with those located on each of the two other chromatograms, to extract blobs which can be considered to be located at the same temporal position. If there are two blobs extracted at the same temporal position on the two chromatograms, a normalized value of the intensity difference between the two blobs is calculated, and the line type of the boundary line for indicating the extracted blob on the display is chosen according to that value.

Abstract: In a GC×GC data processor (23), a modulation time estimation unit (24) creates a one-dimensional chromatogram from chromatogram data items collected by a comprehensive two-dimensional GC, and retrieves a shift time on which a peak position after an entire curve of the chromatogram being shifted in a temporal axis direction coincides with a peak position of the peak on the original chromatogram. Since the resolution of a primary column (12) is low, the same compound is introduced into a secondary column (14) in consecutive modulation times. Accordingly, on the one-dimensional chromatogram, peaks originating from the same compound appear in the respective consecutive modulation times. The interval between the peaks substantially coincides with the modulation time. Therefore, the shift time retrieved as described above is regarded as the modulation time.

Abstract: A two-dimensional chromatogram creator creates a two-dimensional chromatogram based on data obtained for each of two samples. A chromatogram difference calculator creates a two-dimensional differential chromatogram showing the intensity difference between the two two-dimensional chromatograms. A blob detector detects blobs on each chromatogram. A matching-blob extractor compares the blobs located on the differential chromatogram with those located on each of the two other chromatograms, to extract blobs which can be considered to be located at the same temporal position. If there are two blobs extracted at the same temporal position on the two chromatograms, a normalized value of the intensity difference between the two blobs is calculated, and the line type of the boundary line for indicating the extracted blob on the display is chosen according to that value.

Abstract: In a GC×GC data processor (23), a modulation time estimation unit (24) creates a one-dimensional chromatogram from chromatogram data items collected by a comprehensive two-dimensional GC, and retrieves a shift time on which a peak position after an entire curve of the chromatogram being shifted in a temporal axis direction coincides with a peak position of the peak on the original chromatogram. Since the resolution of a primary column (12) is low, the same compound is introduced into a secondary column (14) in consecutive modulation times. Accordingly, on the one-dimensional chromatogram, peaks originating from the same compound appear in the respective consecutive modulation times. The interval between the peaks substantially coincides with the modulation time. Therefore, the shift time retrieved as described above is regarded as the modulation time.

Abstract: A common frequency source is used for the RF voltage generators of an MS/MS type mass analyzer composed of first, second and third main quadrupole units and two pre-rod quadrupole units provided for the first and third main quadrupole units. Since there arises no discrepancy in the frequency and phase of the RF electric field between the adjacent quadrupole units, the (parent as well as daughter) ions can pass through the quadrupole units smoothly and dispersion of the ions is minimized, which improves the sensitivity of the mass analyzer.