Analyst Software Reference Guide - AB Sciex

Terms and ConceptsTable 1-18 HPLC Solvent Compressibility Values (Continued)SolventCompressibility (10 –6 /bar)Chloroform 100Cyclohexane 118Ethanol 114Ethyl acetate 104Heptane 120Hexane 150Isobutanol 100Isopropanol 100Methanol 1201-Propanol 100Toluene 87Water 46Spectral Arithmetic WizardYou can use the Spectral Arithmetic Wizard to perform arithmetic operations using two completechromatograms to create a new chromatogram, which is saved as a new data file. For moreinformation, see the Help.• Subtraction: Use the subtraction option to subtract a control or background from asample.• Addition: Use the addition option to add separate chromatograms together to createa single, more complete profile for a compound. For example, you could createseveral chromatograms using different collision energies and then add thechromatograms together to create a single profile.• Average: Use the average option to statistically improve the profile for a compoundand to generate more reliable spectra.SpectrumA spectrum is the data that is obtained directly from the mass spectrometer and normallyrepresents the number of ions detected with particular mass-to-charge (m/z) values. It isdisplayed as a graph with the m/z values on the x-axis and intensity (cps) represented on the y-axis.Syringe Size Versus Flow RateThe flow rate of a syringe pump depends on the syringe installed in the pump. The followingtables show the relationship between flow rate and syringe size.50 Release Date: August 2011