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During predawn hours on 16 April 2018, surface ozone monitors in a band from roughly Richmond, Virginia, to Philadelphia, Pennsylvania, observed concentration increases of 30-50+ ppbv in a matter of minutes.
The amount is still small compared to Earth, where it is about 1,800 ppbv - meaning for every billion molecules, 1,800 are methane.
Planetary scientists have debated methane's presence on Mars for decades, and Curiosity's iffy detection in 2012--which placed an upper limit of 1.3 parts per billion by volume (ppbv)--didn't help.
Using a specially crafted high-resolution time-of-flight (TOF) mass spectrometer including the Qi, in combination with proprietary PTR technology, the new analyzer achieves a mass resolution of more than 6,000 (up to 10,000 m/[DELTA]m FWHM), a limit of detection below 1 pptv (in 30 sec) and sensitivity of more than 1500 (up to 4500 cps/ ppbv).
Chovelon, "Photocatalytic oxidation of toluene at indoor air levels (ppbv): towards a better assessment of conversion, reaction intermediates and mineralization," Applied Catalysis B: Environmental, vol.
Canister blank concentrations were <0.2 ppbv; the average relative standard deviation (RSD) of calibration relative response factors (RRFs) was 9.31%; average scan and selected ion monitoring (SIM) method detection limits were 0.06 ppbv and 35.9 pptv, respectively; average replicate precision was 6.86 %RSD; and average analytical accuracy for all 65 targeted TO-15 VOCs was 103%.
The global average populationweighted 8-hr maximum ozone concentration was projected to increase by 9.4 parts per billion per volume (ppbv) compared with a simulation of the concentration in 2000, with the largest increases over South Asia (nearly 15 ppbv) and with large increases in the Middle East, Southeast Asia, Latin America, and East Asia.
The atmospheric concentration of [N.sub.2]O continues to rise at a rate of approximate 0.26% per year and has reached a concentration of 319 ppbv ([10.sup.-9] mol/mol) in 2005 (IPCC 2007).
Most concentrations of acetone found in air samples range from 50 to 200 parts per billion by volume (ppbv) (0.05-0.2 ppm).
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