English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

In the present study, the heterogeneous conversion of nitrogen oxide (NO)and nitrogen dioxide (NO2) was studied at atmospheric humidity levelson flame soot surfaces treated with gaseous nitric acid (HNO3).In addition, the heterogeneous reaction of HNO3 on sootwas investigated at atmospheric humidity.For the treatment of soot by pure HNO3 only reversible uptake with asurface coverage of ~1-2x1014 HNO3 cm-2 wasobserved for HNO3 mixing ratios in the range 250-800ppbv. Onlyfor higher HNO3 mixing ratios of >800ppbv the formation of NO andNO2 was observed. The results were not affected by the addition of NO.In none of the experiments with HNO3 the formation of nitrous acid(HONO) was observed. For HNO3 mixing ratios <600ppbv the upper limityields for HONO, NO2 and NO were found to be <0.2%, <0.5%and <1%, respectively. Compared to untreated soot, the productformation of the reaction of NO2 with soot was not significantlyaffected when the soot surface was treated with gaseous HNO3 prior tothe experiment. Only for high surface coverage of HNO3 the formation ofHONO was suppressed in the initial phase of the reaction, probably caused bythe blocking of active sites by adsorbed HNO3.Under the assumption that the experimental findings for the used model flamesoot can be extrapolated to atmospheric soot particles, the results showthat the reactions of HNO3 and HNO3+NO on soot surfaces areunimportant for a "renoxification" of the atmosphere and do not representan atmospheric HONO source. In addition, the integrated HONO yield of ca.1014cm-2 in the reaction of NO2 with soot is notsignificantly influenced by simulated atmospheric processing of the sootsurface by HNO3, and is still too small to explain HONO formation inthe atmosphere

atmospheric chemistry and physics

Heterogeneous conversion of NO&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt; and NO on HNO&amp;lt;sub&amp;gt;3&amp;lt;/sub&amp;gt; treated soot surfaces: atmospheric implications