This product has been discontinued. Please refer to our Discontinued Products for information on replacement analyzers.

This product has been discontinued. Please refer to our Discontinued Products for information on replacement analyzers.

This product has been discontinued. Please reference our replacement analyzer G2508.

This product has been discontinued. Please reference our replacement analyzer SI2108.

This product has been discontinued. Please reference our replacement analyzer SI2205.

This product has been discontinued. Please refer to our Discontinued Products for information on replacement analyzers.

This product has been discontinued. Please reference our replacement analyzer G2201-i.

This product has been discontinued. Please refer to our Discontinued Products for information on replacement analyzers. 

This product has been discontinued. Please reference our replacement analyzer G2131-i.

Stable isotope analysis relies on the simultaneous or near-simultaneous measurement of two individual species. In the case of the Picarro G1101-i and G2101-i gas analyzers, these two species are ¹²C¹⁶O₂ and ¹³C¹⁶O₂, which we denote ¹²C and ¹³C for simplicity. In the G1101-i,…

The Picarro G1101-i and G2101-i gas analyzers provide field measurements of the stable isotope ratio d¹³CO₂ with a precision of 0.3 permil in five minutes. In an isotope ratio mass spectrometry (IRMS) laboratory, it is customary to dry the samples to very low dew points (< - 45C) prior to isotope analysis. For field work, however, drying the…

Exploration of unconventional natural gas reservoirs such as impermeable shale basins through the use ofhorizontal drilling and hydraulic fracturing has changed the energy landscape in the USA providing a vastnew energy source. The accelerated production of natural gas has triggered a debate concerning thesafety and possible environmental impacts of these operations. This study investigates…

A novel instrument, based on cavity-ringdown spectroscopy (CRDS), has been developed for trace gas detection. The new instrument utilizes a widely tunable optical parametric oscillator (OPO), which incorporates a zinc–germanium–phosphide (ZGP) crystal that is pumped at 2.8 μm by a 25-Hz Er,Cr:YSGG laser. The resultant mid-IR beam profile is nearly Gaussian, with energies exceeding 200…

Cavity enhanced spectroscopy (CES) methodology provides a much higher degree of sensitivity than that available from conventional absorption spectrometers. The aim of this chapter is to present the fundamentals of the method, and the various modifications and extensions that have been developed. In order to set the stage, the limitations of traditional absorption spectrometers are…

High fluences inside cavity ring-down spectroscopy optical resonators lend themselves to fluorescence or Raman spectroscopy. An instrument at 488 nm was developed to measure extinction, and fluorescence of aerosols. A detection limit of 6 x 10^-9 cm^-1Hz^-1/2 (0.6 Mm^-1Hz^-1/2) was achieved. The fluorescence spectral power collected from a single fluorescent microsphere was 10 to 20 pW/nm.…

An historical overview of laser-based, spectroscopic methods that employ high-finesse optical resonators is presented. The overview begins with the early work in atomic absorption (1962) and optical cavities (1974) that led to the first mirror reflectivity measurements in 1980. This paper concludes with very recent extensions of cavity-enhanced methods for the study of condensed-phase media…

We describe the application of cavity ring-down spectroscopy (CRDS) to the detection of trace levels of ethylene in ambient air in a cold storage room of a fruit packing facility over a several month period. We compare these results with those obtained using gas chromatography (GC), the current gold standard for trace ethylene measurements in post-harvest applications. The CRDS instrument…

Recent measurements of carbon isotopes in carbon dioxide using near-infrared, diode-laser-based cavity ring-down spectroscopy (CRDS) are presented. The CRDS system achieved good precision, often better than 0.2‰, for 4% CO₂ concentrations, and also achieved 0.15–0.25‰ precision in a 78 min measurement time with cryotrap-based pre-concentration of ambient CO₂…

Researchers investigating global climate change need measurements of greenhouse gases with extreme precision and accuracy to enable the development and benchmarking of better climate models. Existing atmospheric monitors based on non-dispersive infrared (NDIR) sensors have known problems – they are non-linear, sensitive to water vapor concentration, and susceptible to drift. Many cannot…

Eleven instruments for the measurement of ambient concentrations of atmospheric ammonia gas (NH₃), based on eight different measurement methods were inter-compared above an intensively managed agricultural field in late summer 2008 in S. Scotland. To test the instruments over a wide range of concentrations, the field was fertilised with urea midway through the experiment, leading…