Analytical Instruments Documents

rss

JEOL Resources

Documentation in support of your JEOL product.

Rapid Analysis Using Deactivated Fused Silica Tubing(a.k.a. “Guard Column”) as the Sample Inlet (1)

Introduction

Average molecular weight is an important reference for evaluating samples with molecular weight distributions, such as crude oils, which are complex mixtures, or synthetic polymers. Almost all of the ions observed in field desorption (FD) and field ionization (FI) mass spectra are molecular ions because they are both soft ionization methods. As a result, the average molecular weight of a sample can be calculated directly from the masses (or “m/z”) and intensities for all of the ions observed in the FD or FI mass spectra. By applying group-type analysis, the components can be classified into types based on their functional groups and/or unsaturations. Average molecular weight, polydispersity index, or relative abundance of each type can be obtained.

A diesel fuel was analyzed on JMS-T100GC “AccuTOF-GC” with 3 sample introduction methods and the results were compared:

  • Capillary GC / FI
  • Rapid FD in which the analysis time was shorten by ramping the emitter current much faster than for conventional analyses on double-focusing mass spectrometers
  • Blank tube inlet / FI in which a fused silica tube was used to connect the GC injector and the ion source

Showing 0 Comment



Comments are closed.

Other Resources

The following resources are available for the JEOL Analytical Instruments:

Media

Corona - Glow Discharge (DART Ion Source)

February 22, 2020
158