The Selective Dual Input (SDI) instrument is an on-line time-of-flight mass analyser (TOFMS) providing rapid and sensitive gas analysis for environmental monitoring and research applications.
Gas Inlet System
The SDI-TOF-MS-2000 instrument is fitted with two selectable ambient air sample inlets:
Capillary inlet for rapid (<1 second) high sensitivity analysis of inorganic gases such as CO, CO2, NO, NOx , N2O, Xe, Kr, SO2, O2 and others at less than 1ppm to percent concentrations.
Membrane inlet for very high sensitivity analysis of volatile organic compounds at the ppt and ppb level within one minute. Compounds of interest include benzene, toluene, xylene (BTX), trichloroethylene, tetrachloroethylene, methane, ethene, formaldehyde, styrene and most other toxic organic compounds of environmental interest.
The Mass Spectrometer
The mass resolution and mass accuracy of a TOF-MS compared to a quadrupole mass spectrometer means we can separate common organic and inorganic interferences and more readily identify unknowns. Similarly the TOF-MS has a large mass range from 1-2000 amu ensuring that all gases of environmental interest can be detected.
The Data System
Data is displayed on a PC. The industry standard software has been customised to make the collection of spectra a simple press of a virtual button. Provide the automatic analysis of mixtures that presents the identified sample gas components concentrations in tabular form. The software allows the user to monitor trends in multiple gases over long periods of time.
Analytical Modes
The SDI-TOF-MS-2000 is highly attractive because it offers real-time, high time resolution, high sensitivity detection of all gas species in parallel. All masses are collected, preserving the maximum amount of information.
Mass Spectra
The instrument will generate single mass spectra from 0.5 seconds to many minutes duration if required.
High Time Resolution Mode
In this mode for instance, it is possible to request full mass spectra at time slices of as little as 100ms. Alternatively, one might request the time evolution plot of any species with a time resolution of 100ms. This type of functionality is useful for extracting the most information from short-term experiments.
Process Monitor Mode
Where the experiment takes places over many hours or even days, the instrument operates in a mode where selected species are plotted 'live' to a graph as a function of elapsed experiment time essentially a process monitor type operation.