先进材料表征技术-(II).pptVIP

Advanced Technology for Materials Characterization(Part IV) By Dr. Yejun Qiu Characteristics: Time of flight (TOF): 100 °C (1 min) to 250 °C at 10 °C/min (Hold 4.00 min) for a total run time of 20 min. Oven Program: He at 35 cm/sec (constant flow) Carrier Gas Flow: 1 μL Injection Volume: Split (20:1) Injection Mode: 250 °C Transfer Line Temperature: 250 °C Inlet Temperature: Restek Stabilwax (30 m X 0.25 mm id X 0.25 μm df) with a 5 m retention gap (or equivalent) Column: Use 50% aqueous acetonitrile in the wash vials for cleaning the syringe between injections. This removes sample residue that may not be soluble in other wash solvents. This will reduce injector errors. Note: Alterations to the GC temperature program may be used to help overcome interferences. Significant additional resolution may be obtained by decreasing the temperature ramp over relevant portions of the chromatogram. This will alter retention times for the analytes and they would need to be re-established. GC Conditions 230 °C (Source); 150 °C (Quad) MS Temp: 4 minutes Solvent Delay: 100 Threshold: 2 (Scan Rate of about 4 scans/sec) Sampling Rate: 29 - 400 amu Scan Range: Standard Spectrum autotune Tune: MS Conditions (Full Scan Mode)  a Start Times may need to be adjusted based upon the retention time of standards on your system.b Dwell times should be adjusted to produce a cycle time of about 4 scans/secc Percent relative abundance with respect to the ion of highest abundance.d M is the Molecular Ion. 61(100) 60(13) 43(78) 31(40) 12.0 Glycerin 76(12) 75(24) 45(100) 31(11) 9.0 Diethylene Glycol 58(68) 57(73) 43(22) 31(100) 7.5 1,3-Propanediol 62 (M) d(4) 43(8) 33(35) 31(100) 6.6 Ethylene Glycol 61(5) 45(100) 43(15) 31(11) c 4.0 1,2-Propanediol 4 3 2 1 Selected Ions b Start Time a(min) Group MS Conditions (SIM Mode).This is provided primarily for information only since it is unlikely that SIM will need to be utilized.There are a lot of potential interferences with th