High-resolution Aerosol Mass Spectrometer
High-resolution Aerosol Mass Spectrometer - Related Videos
01:16
Mass Spectrometers
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2024
This lesson details the instrumentation of a mass spectrometer—a physical instrument to perform mass spectrometry on analyte molecules and record the characteristic mass spectra. This is achieved via three chief functions: Conversion of the gas-phase analyte atoms/molecules into a beam of positive or negative charged ions by ionization. Separation of the charged species based on their mass-to-charge ratio. Recording the relative abundance of each type of ion. In the ionization chamber of...
11:18
A Practical Guide on Coupling a Scanning Mobility Sizer and Inductively Coupled Plasma Mass Spectrometer (SMPS-ICPMS)
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Cited by 9 •
2017
In this work a practical guide is provided, describing the different steps to establish the coupling of SMPS and ICPMS systems, and how to use them. Three descriptive examples are presented.
01:14
NMR Spectrometers: Resolution and Error Correction
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2024
When magnetic nuclei in a sample achieve resonance and undergo relaxation, the signal detected in NMR is an approximately exponential free induction decay. Fourier transform of an exponential decay yields a Lorentzian peak in the frequency domain. Lorentzian peaks in an NMR spectrum are defined by their amplitude, full width at half maximum, and position, where the peak width is governed by the spin-spin relaxation time alone. In real experiments, however, the applied magnetic field is rendered...
10:11
Whole-Body Nanoparticle Aerosol Inhalation Exposures
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Cited by 51 •
2013
A whole-body nanoparticle aerosol inhalation exposure facility was constructed for nano-sized titanium dioxide (TiO2) inhalation toxicology studies. This system provides nano-TiO2 aerosol test atmospheres that have: 1) a steady mass concentration; 2) a homogenous composition free of contaminants; and 3) a stable particle size distribution during aerosol generation.
09:34
Extraction and Characterization of Surfactants from Atmospheric Aerosols
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Cited by 26 •
2017
Methods are presented for the targeted extraction of surfactants present in atmospheric aerosols and the determination of their absolute concentrations and surface tension curves in water, including their Critical Micelle Concentration (CMC).
FAQs
The instrument first focuses sampled submicron aerosols into a vacuum, then flash-vaporizes the particles so their chemical constituents can be analyzed. Electron-impact ionization converts these constituents into ions, and a time-of-flight analyzer separates them according to mass-to-charge ratio. This sequence transforms airborne particulate material into spectra that can be interpreted chemically.
High mass resolution helps distinguish ions that share the same nominal mass but differ in their more precise mass values. That separation provides a stronger basis for estimating elemental composition within atmospheric organic aerosol. As a result, researchers can interpret particle chemistry in greater detail rather than treating several chemically different signals as one indistinguishable peak.
Size-resolved measurements show how chemical composition varies among airborne particles of different sizes within the sampled submicron range. This information helps connect composition with particle formation, atmospheric transport, aging, and removal. Examining size and chemistry together therefore provides more environmental context than a single composition measurement without particle-size information.
After electron-impact ionization, the resulting ions enter a time-of-flight system. Their flight times differ according to mass-to-charge ratio, allowing the instrument to produce a mass spectrum. High-resolution measurement then supports separation of closely overlapping ion signals and estimation of elemental composition, which helps researchers interpret the chemical character of atmospheric particulate matter.
A typical workflow begins by sampling submicron airborne particles and introducing them into the instrument’s vacuum region. The particles are focused, flash-vaporized, and ionized by electron impact before time-of-flight separation generates spectra. Researchers then examine the size-resolved chemical signals to characterize particulate matter and relate its composition to atmospheric processes.
Researchers use the measurements to identify organic aerosol sources and follow changes associated with atmospheric oxidation and aging. The resulting chemical information can be compared with particle size and environmental behavior, helping distinguish how particulate material forms and evolves. This makes the technique useful for studying changing aerosol composition rather than only its presence.
The measurements provide chemical and size-related evidence about atmospheric particulate matter, allowing researchers to evaluate its links with air-quality and climate influences. They can also examine how particle composition relates to transport, formation, and removal processes. These connections help place observed aerosol chemistry within broader environmental patterns and atmospheric behavior.