Concerns about the health effects of nitrogen dioxide (NO2) and its role in forming deleterious atmospheric species have made it desirable to have low-cost, sensitive ambient measurements of NO2. We have developed a continuous-wave laser-diode laser-induced fluorescence (LIF) system for NO2 that operates at ambient pressure, thereby eliminating the need for an expensive pumping system. The curr...

Tyrosine hydroxylase (TH) is the initial and rate-limiting enzyme in the synthesis of the neurotransmitter dopamine. TH is inhibited and nitrated at tyrosine residues in vitro by the reactive nitrogen species peroxynitrite and nitrogen dioxide (NO2) and in vivo by drugs that damage dopamine neurons. Tetrahydrobiopterin, which is the essential cofactor for TH and is concentrated in dopamine neur...

Exposure to nitrogen dioxide (NO2), a common oxidant airborne pollutant, has been shown to cause reversible effects on lung function and airway responsiveness, in addition to airways inflammation. However, there have been conflicting reports concerning NO2-induced airway hyperresponsiveness. In the present study, we investigated the isotonic smooth muscle response in isolated human bronchi prev...

Nitrogen dioxide (NO2) is a free radical-producing oxidant gas. Inhalation of NO2 could cause airway inflammation, and decrease immune function. This experiment tested the hypothesis that exposure to NO2 would: 1) increase leukocytes in bronchoalveolar lavage (BAL); and 2) change the distribution of lymphocyte subsets and activation in BAL and peripheral blood (PB). Using a counter-balanced, re...

Rates of nitrogen dioxide (NO2) absorption and sulfide oxidation were measured in a highly characterized stirred cell contactor at 55 °C, with O2 present in the gas phase. The rate constant of the reaction between NO2 and sul-fide at 55 °C was determined to be 26.4 x105 M-1sec-1. A reaction mechanism was proposed that is consistent with the kinetic data. NO2 absorption initiates sulfide oxidati...

SCHMUTZ P., TARJAN J., GÜNTHARDT-GOERG M. S., MATYSSEK R. & BÜCHER J. B. 1995. Nitrogen dioxide a gaseous fertilizer of poplar trees. Phyton (Horn, Austria) 35 (2): 219-232, 4 figures. English with German summary. Cuttings of a poplar clone (Populus x euramericana 'Dorskamp') were exposed to filtered air and to filtered air with 80 to 135 nl I" NO2 added in climate chambers during 12 weeks. Thr...

In the present study, UV light induced desorption of nitrogen dioxide (NO2) on pristine graphene based gas sensor is used to improve the sensing performance. Compared to the sample without UV light exposure, the response is 12%, 18% and 21% for NO2 concentrations of 1, 3 and 5 ppm. In addition, the recovery could be speeded up by UV irradiation. The sensor shows good behavior of repeatability w...

BACKGROUND With growing urbanization, traffic has become one of the main sources of air pollution in Nepal. Understanding the impact of air pollution on health requires estimation of exposure. Land use regression (LUR) modeling is widely used to investigate intraurban variation in air pollution for Western cities, but LUR models are relatively scarce in developing countries. In this study, we d...

Experiments were performed to investigate the effects of sulfur dioxide (O-10 ppm) and chlorine (O-15 ppm) on ozone and nitric oxide concentrations in irradiated mixtures of nitrogen dioxide (1-5 ppm) and air. The mixtures were irradiated by ultraviolet fluorescent lamps while flowing at a steady speed through a 9 m long, 15.2 cm i.d. Pyrex tube. The presence of sulfur dioxide produced no measu...