Mass spectrometry is powerful tool for environmental and atmospheric chemistry analysis. Modern mass spectrometers demonstrate low detection limits, high sensitivity, and high resolving power. However, such high performance is not always enough to identify ambient ion clusters due to the clusters braking at the atmospheric pressure-to-vacuum interface of mass spectrometer. This study presents a...

We describe a novel liquid beam mass spectrometer, based on a recently discovered nanosecond laser desorption phenomenon, @W. Kleinekofort, J. Avdiev, and B. Brutschy, Int. J. Mass Ion. Processes 152, 135 ~1996!# which allows the liquid-to-vacuum transfer, and subsequent mass analysis of pre-existing ions and ionic associates from liquid microjets of aqueous solutions. The goal of our novel tec...

One limitation in the growing field of ambient or direct analysis methods is reduced selectivity caused by the elimination of chromatographic separations prior to mass spectrometric analysis. We explored the use of high-field asymmetric waveform ion mobility spectrometry (FAIMS), an ambient pressure ion mobility technique, to separate the closely related opiate isomers of morphine, hydromorphon...

First of all, the detection limit (or calibration range), in general, shifts lower by two orders of magnitude. Quantitative analysis of food or environmental samples for organic contaminants at parts-per billion (ppb) or parts-per-trillion (ppt) levels, places additional emphasis on all parts of the GC/MS/MS system (inlet, capillary column, and mass spectrometer ion source, in particular) to be...

A cascade arc is used as a source for a hydrogen/argon particle beam. The plasma is produced at thermal plasma conditions in the pressure range of 0.1 to 1 bar. It is expanded with a high velocity into a vacuum chamber. Measurements with a Langmuir double probe and with a mass spectrometer are performed. The resulting parameters of the plasma and the extracted ions are discussed. Molecular proc...

An inductively coupled plasma/selected-ion flow tube (ICP/SIFT) tandem mass spectrometer has been employed in a systematic survey of the room-temperature kinetics of reactions of NO with 13 atomic lanthanide cations from Ce+ to Lu+ (excluding Pm+). The atomic ions are produced at ca. 5500 K in an ICP source and are allowed to decay radiatively and to thermalize by collisions with Ar and He atom...

Surface mass spectrometry methods can be difficult to use effectively with low cost, portable mass spectrometers. This is because commercially available portable (single quadrupole) mass spectrometers lack the mass resolution to confidently differentiate between analyte and background signals. Additionally, current surface analysis methods provide no facility for chromatographic separation and ...

A time-of-flight mass spectrometer (TOF-MS) developed in our laboratory at Isfahan University of Technology is described here. The TOF-MS instrument uses laser as the ionization source which provides an opportunity to investigate the ions formed in laser ablation or desorption. The TOF-MS has an ionization chamber containing an accelerator and an ion lens to focus the ions into a one meter line...

The applicability of a new mass spectrometric technique, DART (direct analysis in real time) has been studied in the analysis of the calli of Taxus wallichiana. The intact callus samples were directly analyzed by holding them in the gap between the DART source and mass spectrometer for measurements. Five C-14 oxygenated taxoids were characterized from the analysis of the calli of the Taxus wall...