Note: A versatile mass spectrometer chamber for molecular beam and temperature programmed desorption experiments.

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...

Design, Construction and Calibration of a Laser Ionization Time-of-Flight Mass Spectrometer

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...

RHEED AND TPD STUDIES OF THE EFFECT OF PARTICLE SIZE ON CO DESORPTION FROM Al2O3 SUPPORTED Pd AND Rh MODEL CATALYSTS

Transition metals in form of small supported particles are frequently used in heterogeneous catalytic reactions. One point of actual interest concerns the reactivity of low co-ordination sites characteristic for particle surface. The non continuous epitaxial layers of Pd and Rh were grown on insulator substrates (Al2O3) by molecular beam epitaxy. The reflection high energy electron diffraction ...

Employing a cylindrical single crystal in gas-surface dynamics.

We describe the use of a polished, hollow cylindrical nickel single crystal to study effects of step edges on adsorption and desorption of gas phase molecules. The crystal is held in an ultra-high vacuum apparatus by a crystal holder that provides axial rotation about a [100] direction, and a crystal temperature range of 89 to 1100 K. A microchannel plate-based low energy electron diffraction/r...

Microsystem with integrated capillary leak to mass spectrometer for high sensitivity temperature programmed desorption