Sulfate-nitrate-ammonium aerosols over China: response to 2000–2015 emission changes of sulfur dioxide, nitrogen oxides, and ammonia Y. Wang, Q. Q. Zhang, K. He, Q. Zhang, and L. Chai Ministry of Education Key Laboratory for Earth System Modeling, Center for Earth System Science, Institute for Global Change Studies, Tsinghua University, Beijing, China School of Environment, Tsinghua University,...

Ways to reduce nitrogen oxide emissions One of MTU ś aims for its engines is to reduce the emission of soot particles and nitrogen oxides in order to achieve compliance with increasingly strict emissions regulations around the world. The main approach pursued by MTU is low-emission combustion, in other words an internal engine solution. However, this means taking into account a basic principle ...

The role of nitrogen and oxygen chemistry in the interstellar medium is still rather poorly understood. Nitric oxide, NO, has been proposed as an important precursor in the formation of larger N- and O-bearing species, such as hydroxylamine, NH2OH, and nitrogen oxides, NO2 and N2O. The topic of this study is the solid state consumption of NO via oxygenation and the formation of NO2 and other ni...

Although it is generally recognized that SOz and NOx (s NO + NOz) are the precursors of the strong acids (i.e., HzS04 and HN03) found in precipitation,! the detailed mechanisms for the oxidation of these compounds and their incorporation into atmospheric liquid water are not fully understood. In principle, the incorporation of acids into cloudor rainwater can take either or both of two pathways...

Fuel combustion is a significant source of numerous air pollutants, which reduce local air quality, and affect global tropospheric chemistry. Satellite observations of nitrogen dioxide, emitted by combustion processes, allow for robust monitoring of atmospheric concentrations at high spatial resolution on continental scales. Here we evaluate changes in tropospheric NO(2) concentrations over Eur...

Nitrous acid (HONO) may be generated by heterogeneous reactions of nitrogen dioxide and direct emission from combustion sources. Interactions among nitrogen oxides and ozone are important for outdoor photochemical reactions. However, little is known of indoor HONO levels or the relationship between residential HONO, NO(2), and O(3) concentrations in occupied houses. Six-day integrated indoor an...

Air pollution in the Los Angeles area is Characterized by a decrease in visibility, crop damage, eye irritation, objectionable odor, and rubber deterioration. These effects are attributed to the release of large quantities of hydrocarbons and nitrogen oxides to the atmosphere. The photochemical action of nitrogen oxides oxidizes the hydrocarbons and thereby forms ozone, responsible for rubber c...

here are six main classes of gaseous contaminants which are routinely described in Tautomotive exhaust (a term which will be used here to refer to both automobile and diesel exhaust). As shown in Table 1, carbon monoxide (CO) is the largest component of automobile exhaust whereas the oxides of nitrogen (NO ) constitute the main components of diesel exhaust. x Even though nitrogen oxides contrib...

Three strains of heterotrophic denitrifying bacteria were cultured in artificial seawater medium under trace metal clean conditions to investigate their physiological response to changes in copper concentration. Decreasing the copper concentration in cultures of Pseudomonas stutzeri and Paracoccus denitrificans resulted in accumulation of nitrous oxide (N2O) gas compared to copper-replete cultu...

Ever since the industrial revolution, there has been a growing excess of nutrients and related emissions into the atmosphere (ammonia, nitrogen oxides and nitrous oxide) and into groundwater and surface water (nitrate), leading to a large range of cascading environmental impacts. Vehicular traffic, sewage and animal husbandry are the main sources of oxidized and reduced forms of Nr. This report...