Gaseous nitrous acid (HONO) and nitrogen oxides (NO_x) emission from gasoline and diesel vehicles under real-world driving test cycles

Abstract

Photolysis of HONO is a dominant source of morning OH radicals. Conventional traffic-induced HONO/NO ratio of 0.8% has possibly linked to underestimation of the total HONO budget and consequently underestimation of OH radical budget. The recently reported HONO/NO ratio of ~1.6% was used to stimulate HONO emission, which resulted in increased HONO concentrations during morning peak hours and its impact of 14% OH increment in the morning. However, the results were still lower than the measured concentrations. More studies should be conducted to establish an updated traffic-induced HONO/NO ratio.

First detection of a key intermediate in the oxidation of fuel + NO systems: HONO

“…However, the detailed analysis of field campaign data reveals that HONO formation paths are far from being understood and major HONO sources are still to be discovered [8,9]. Another possible source for HONO is the direct emission in the exhaust gases from internal combustion engines [10]. The detection of this species in exhaust gases was so far not directly performed in the gas phase, but in the liquid phase after absorption of HONO in water forming nitrite ions [10].…”

Introductory lecture: atmospheric chemistry in the Anthropocene

“…129,[138][139][140][141][142][143][144] Despite this, the relative importance of sources of atmospheric HONO are not yet well dened or quantied. 145 There are direct emissions of HONO from combustion, [146][147][148][149][150][151][152][153] and the reaction of OH with NO also generates a small steadystate HONO concentration during the day (since HONO photolyzes rapidly back to OH + NO).…”

Microbiological Diversity Demonstrates the Potential which Collaboratively Metabolize Nitrogen Oxides ( NOx) under Smog Environmental Stress

“…However, efficient sewage treatment leaded to increased emissions of N2O because insufficiency of dinitrogen reductase activity can't complete the transformation process from N2O to N2 gas. N2O can be transformed into NO and constantly changed into NO2 [2,5,6,9]. To increase the enzymatic activity can be an alternative program.…”

“…The smog will be reduced and eliminated if the emission of NOx is controlled effectively [1][2][3][4][5][6][7][8][9]. Currently, energy conservation & emission reduction technology is carried out to tackle its notorious smog problem.…”

“…SO2）and nitrogen oxides（i.e. NOx）produced by coal and fuel motor vehicle [1][2][3][4][5][6][7][8][9][10][11]. In addition, nitrogen oxides can catalyse photochemical reaction to increase pollution [1][2][3][4][5][6][7][8][9][10][11].…”