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 work, we performed chassis dynamometer experiments toinvestigate the emissions and secondary organic aerosol (SOA) formationpotential of intermediate-volatility organic compounds (IVOCs) from anon-road Chinese gasoline vehicle. High IVOC emission factors (EFs) anddistinct volatility distribution were recognized. The IVOC EFs for theChina V vehicle ranged from 12.1 to 226.3  mg per kilogram fuel , witha median value of 83.7  mg per kilogram fuel , which was higher thanthat from US vehicles. Besides, a large discrepancy in volatility distributionand chemical composition of IVOCs from Chinese gasoline vehicle exhaust wasdiscovered, with larger contributions of B14 – B16 compounds(retention time bins corresponding to C 14 -C 16 n -alkanes) and a higherpercentage of n -alkanes. Further we investigated the possible reasons thatinfluence the IVOC EFs and volatility distribution and found that fueltype, starting mode, operating cycles and acceleration rates did have animpact on the IVOC EF. When using E10 (ethanol volume ratio of 10 %, v / v )as fuel, the IVOC EF of the tested vehicle was lower than that usingcommercial China standard V fuel. The average IVOC-to-THC (total hydrocarbon) ratios forgasoline-fueled and E10-fueled gasoline vehicles were 0.07±0.01 and 0.11±0.02 , respectively. Cold-start operation had higher IVOC EFsthan hot-start operation. The China Light-Duty Vehicle Test Cycle (CLTC) produced70 % higher IVOCs than those from the Worldwide Harmonized Light VehiclesTest Cycle (WLTC). We found that the tested vehicle emitted more IVOCs atlower acceleration rates, which leads to high EFs under CLTC. The onlyfactor that may influence the volatility distribution and compoundcomposition is the engine aftertreatment system, which has compound andvolatility selectivity in exhaust purification. These distinctcharacteristics in EFs and volatility may result in higher SOA formationpotential in China. Using published yield data and a surrogate equivalentmethod, we estimated SOA formation under different OA (organic aerosol) loading and NO x conditions. Results showed that under low- and high-NO x conditions atdifferent OA loadings, IVOCs contributed more than 80 % of the predictedSOA. Furthermore, we built up a parameterization method to simply estimatethe vehicular SOA based on our bottom-up measurement of VOCs (volatile organic compounds) and IVOCs,which would provide another dimension of information when considering thevehicular contribution to the ambient OA. Our results indicate thatvehicular IVOCs contribute significantly to SOA, implying theimportance of reducing IVOCs when making air pollution controlling policiesin urban areas of China.

atmospheric chemistry and physics

Measurement report: Distinct emissions and volatility distribution of intermediate-volatility organic compounds from on-road Chinese gasoline vehicles: implication of high secondary organic aerosol formation potential