Thermal Desorption Chemical Ionization Mass Spectrometer for Ultrafine Particle Chemical Composition

“ Chemical Analysis of Diesel Nanoparticles Using a Nano - DMA / Thermal Desorption Particle Beam Mass Spectrometer ”

A Chemical Ionization Mass Spectrometer for Ambient Measurements of Ammonia

This study presents a chemical ionization mass spectrometer (CIMS) for fast response, in-situ measurements of gas phase ammonia (NH3). The NH3 background level detected with the CIMS ranged between 0.3–1 ppbv, with an uncertainty of 30 pptv under optimized conditions. The instrument sensitivity varied from 4–25 Hz/pptv for >1 MHz of reagent ion signals (protonated ethanol ions), with a 30% unce...

A field-deployable, chemical ionization time-of-flight mass spectrometer

We constructed a new chemical ionization timeof-flight mass spectrometer (CI-TOFMS) that measures atmospheric trace gases in real time with high sensitivity. We apply the technique to the measurement of formic acid via negative-ion proton transfer, using acetate as the reagent ion. A novel high pressure interface, incorporating two RF-only quadrupoles is used to efficiently focus ions through f...

Use of a Thermal Desorption Particle Beam Mass Spectrometer for Studies of Secondary Organic Aerosol Formation

As part of a research program focusing on studies of the chemistry of gas-to-particle conversion, we have recently developed a new instrument for particle chemical analysis. This instrument, which we refer to as a thermal desorption particle beam mass spectrometer (TDPBMS), can be used for real-time, quantitative analysis of the components of organic particles, at least within the ~0.02-0.5 mic...

Selective Reagents for Chemical Ionization Mass Spectrometry

Much of the power of chemical ionization mass spectrometry stems from the finding that the characteristics of the Cl mass spectrum produced is dependent on both the nature of the reagent gas and the type of ion-molecule reaction used to ionize the sample. Different structural information can be obtained with different reagent gases. As a consequence, it is possible to control the type and quant...