Atmospheric Chemistry

Layout of the NO Detection System

Induced Fluorescence NO Detector and Method

US Patent 11,415,859 – Exclusive and Non-Exclusive Patent Licenses Available Background Nitric oxide (NO) is important to radical chemistry in Earth’s atmosphere. In the troposphere the catalytic reaction of NO with the hydroperoxy and organic peroxy radicals NO+RO2/HO2 →NO2 +RO/HO is frequently the rate-limiting step for the production of tropospheric ozone (O3), and causes the buildup of O3 from anthropogenic emissions of NO. Oxidation of NO also results in the formation of nitric acid, and consequently nitrate aerosols and nitrogen deposition. Current research in atmospheric science seek to  understand radical chemistry cycling in low NO regimes. The ability to measure atmospheric NO at very low mixing ratios and with low uncertainty will be crucial to address questions in atmospheric chemistry research and in other fields of research for the foreseeable future. For example, measurement of NO in exhaled human breath is also an important diagnostic of various medical conditions including asthma. Summary of the Invention NOAA has developed a device and method to measure nitric oxide (NO) in the atmosphere with laser induced fluorescence using a fiber laser source to excite NO near 215 nm (A(v’=1) <- X(v’’=0) electronic transition). The technique can distinguish NO isotopologues (14N16O, 15N16O, 14N18O) and can be used to measure the isotope ratios. Nitrogen dioxide can be measured by photolyzing it and measuring the nitric oxide product. The technique uses a light source of sufficient power in the wavelength range of 300-410 nm, and illuminates the sampled gas either in the sampling inlet or in the fluorescence detection cell. The invention can be used to measure NO with very high precision (low part per trillion mixing ratios). Licensing Information NOAA is seeking qualified licensees to manufacture and sell this technology, which has been Patented in the United States.  Interested parties should contact the NOAA TPO at noaa.t2@noaa.gov for more information. 

S Curved Time of Flight Chamber

S-Curve Time of Flight Mass Spectrometer

US Patents 9,761,431 and 10,438,788 – Exclusive and Non-Exclusive Patent Licenses Available Time-of‐flight mass spectrometers are commonly used in analytical chemistry and many other applications. They contain a region where ions travel toward a detector. NOAA scientists have developed a new geometry that has improved performance over existing designs. The new innovation is to use two successive sectors, with the second one reversed, in a geometry resembling an “s”. The result is that the output ion beam is parallel to the input ion beam and that the entire geometry folds into a very compact volume. A second benefit to the design is that certain higher-order aberrations cancel when the ion beam makes two identical but opposed turns (e.g. a right-hand turn followed by a left-hand turn). NOAA is seeking qualified licensees to manufacture and sell this patented device.  Interested companies should contact the NOAA TPO at noaa.t2@noaa.gov for more information.  Shaped Time of Flight Chamber. Machined prototype. Credit: NOAA

Four Channel Cavity Ringdown NOy Detector

The instrument has lower power, size, weight, and vacuum requirements than a chemiluminescence-based instrument while approaching its sensitivity, precision and time response. In the NOy CRDS instrument of the present invention, NOy and its components are converted into NO2 by thermal decomposition (TD) in a fused silica inlet (henceforth referred to as quartz, following convention), followed by the addition of ozone to convert NO to NO2. NO2 is then measured using a cavity ring-down spectroscopy instrument, utilizing a 405 nm laser. The device may comprise four parallel channels, each driven by the same laser, to measure NO, NO2, NOy and O3, respectively, such that overall NOy may be measured, as well as its components NO, NO2, as well as ozone (O3).