Chemical Processes & Instrument Development: Instruments

Instruments in our laboratory are primarily used to study fundamental processes that occur in the atmosphere via the characterization of the chemical and physical properties of atmospheric trace species. Laboratory instruments are used in the development of experimental methods to measure the reactivity and photochemistry, as well as, the optical and physical properties of stable, transient, and radical species. The experimental apparatus and methods used in our laboratory are designed to selectively detect species with high sensitivity under various temperature and pressure conditions on time scales ranging from nanoseconds to hours. No individual instrument is, however, capable of meeting all the requirements necessary to study all processes. Therefore, the instruments described below are commonly used in combination to develop a more comprehensive picture for a specific species or process.

Instrument	Abbreviation	Applications
Atomic Resonance Fluorescence	RF	Reaction rate coefficient measurements, photolysis quantum yields (H, O, Cl, Br)
Cavity Ring-down Spectroscopy (co-linear photolysis)	CRDS	Temperature and pressure dependent reaction rate coefficient measurements, product yields, absorption spectra, photolysis quantum yields
Chemical Ionization Mass Spectrometer	CIMS	Temperature dependent reaction rate coefficients, reaction product yields, heterogeneous chemistry/uptake measurements
Diode Array Spectrometer	DA	UV absorption spectra, photolysis quantum yields
Dual Wavelength Cavity Ring-down Spectroscopy	DW-CRDS	Reaction rate coefficients, product yields, spectrum measurements, photolysis quantum yields
ElectroSpray Ionization Mass Spectrometer	ESI-MS	Aqueous-phase chemistry, reaction mechanisms and product yields
Fourier Transform Spectrometer	FTIR	High-resolution infrared absorption/emission spectra, absorption cross sections, reaction rate coefficients (RR), reaction product yields, reaction mechanisms
Laser Induced Fluorescence	LIF	Temperature and pressure dependent reaction rate coefficient measurements, product yields, OH photolysis quantum yields
New Particle Formation	NPF	New particle formation mechanisms, nucleation and condensation yields
Relative Rate Reactor	RR	Temperature and pressure dependent reaction rate coefficients (OH, Cl, O₃, and NO₃), reaction mechanisms, reaction product yields
Solubility and Hydrolysis	S&H	Henry's law coefficient measurements, hydrolysis rate coefficients and product yields