Analytical Instrument Documents

Perfumes are known to be complex mixtures that typically contain a variety of compounds. Their scents are strongly affected by these compounds and their quantity ratios. Additionally, these ratios can change over time, thus changing the perfume’s scent. Two-dimensional gas chromatography/time-of-flight mass spectrometry (GCxGC-TOFMS) is an effective technique for measuring complex samples like perfumes. Using electron ionization (EI) allows for database searches. However, these searches may result in mis-assignments without the additional high-resolution molecular ion information that can be generated through soft ionization techniques. In this study, we used GCxGC-HRTOFMS with EI and the soft ionization techniques of FI (Field Ionization) and PI (Photoionization). Additionally, we measured the changes in intensity over time for the top note/middle note/base note compounds.

Compounds which are generated upon heating polymer materials include monomers, additives and fragments characteristic of the polymer materials. Low molecular weight compounds generated by pyrolysis and/or locally desorption are observed. The relationship between the behavior of evolved gas compounds and the heating temperature is important for understanding the chemical characteristics of polymer materials. A gas chromatograph (GC) - mass spectrometer (MS) with thermogravimetric / differential thermal analyzer (TG/DTA) or pyrolyzer (Py) is generally used to identify the thermally evolved gas compounds from polymer materials. However, GC with a low-resolution MS such as quadrupole MS (QMS) may have difficulty monitoring low molecular-weight compounds generated by heating, since the GC is not used to provide chromatographic separation and QMS has poor mass spectrometric separation in the low mass region. (For example, N2+·, CO+· and C2H4+· are detected as the same signal of nominal mass m/z 28.) We report the use of Py - GC - high resolution time-of-flight MS (HRTOFMS) for monitoring the low-molecular weight compounds generated upon heating the polymer materials. This report focuses on the generation of low molecular weight compounds near m/z 18, 28, and 4.

This report shows the analyses of the phenolic polymer antioxidants shown in Fig. 1. These samples were analyzed by using the AccuTOF-GCV with both direct insertion probe（DIP）electron ionization (EI) and field desorption (FD).

Three polydimethylsiloxane compounds: octamethylcyclotetrasiloxane (sample 1), decamethylcyclopentasiloxane (sample 2) and octa(dimethylsiloxy)silsesquioxane (sample 3), were analyzed using a GC/TOFMS. The first two samples are relatively small molecules with molecular weights of 296 and 370, respectively, so they were introduced into the system through the mass reference sample inlet (reservoir). Sample 3 is a much bigger molecule with a molecular weight of 1,016 that could not be introduced through the reservoir. As a result, this sample was introduced by injecting it into the GC.

A UV and visible light curing adhesive is a liquid composed of monomer, oligomer, initiator and additives. These adhesives cure over a short period of time when they are exposed to the appropriate light. In this report, a photo polymerization initiator found in a UV light curing adhesive was analyzed by electron ionization (EI) and field ionization (FI) using the high resolution and high mass accuracy capabilities of the AccuTOF-GC.

Organogermanium compounds are organometallics that contain a carbon to germanium chemical bond. Germanium shares group 14 in the periodic table with silicon, tin and lead and the chemistry of organogermanium is somewhat similar to that of organosilicon compounds and organotin compounds. While metallic germanium is widely used in semiconductor devices, infrared light sensors, etc., organogermanium is advocated as a non-toxic alternative to many toxic organotin reagents. In this work, we report the analyses of organogermanium compounds by field desorption (FD) using the JMS-T100GC “AccuTOF-GC” time-of-flight mass spectrometer.

Ionic liquids are liquids that are predominantly comprised of ions and ion-pairs. More recently, this term has generally referred to salts that are in a liquid state at room temperature. Ionic liquids are electrically conductive and have an extremely low vapor pressure. Additionally, many of these liquids have low combustibility and excellent thermal stability. As a result of these properties, ionic liquids are expected to find many applications as functional materials.

Comprehensive two-dimensional gas chromatography (GCxGC) in combination with high-resolution mass spectrometry (HRMS) is a powerful tool for the analysis of complex mixtures. However, new software tools are required to facilitate the interpretation of the rich information content in GCxGC/HRMS data sets. In this work, we analyzed a dust sample collected from an electronics recycling facility by using GCxGC in combination with a new high-resolution time-of-flight (TOF) mass spectrometer. Nontraditional Kendrick Mass Defect (KMD) plots were used to identify halogenated contaminants in an electronics waste sample. Database search results combined with elemental composition determinations from exact-mass data were used to identify (potential) persistent organic pollutants (POPs).

Comprehensive two-dimensional gas chromatography (GC×GC) is a kind of continuous heart-cut GC system. Two different types of columns are connected via a modulator in the same GC oven. By using the two columns together, this technique provides very high separation capabilities when compared to one- dimensional GC analysis. This report shows the difference of separation result for diesel oil when 2 different sets of combined columns are used with GC×GC-HRTOFMS (FI).

A commercially available polyoxypropylene (PO) - polyoxyethylene (EO) block copolymer was analyzed by using the JMS-T100GC “AccuTOF GC” field desorption (FD) method. A group-type analysis was performed on the resulting mass spectrum.