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

PM10 and size-segregated samples were simultaneously collected at Mt. Hua (2060 m a.s.l.) and Mt. Tai (1545 m a.s.l.) in central and east coastalChina during spring, 2009 including an intensive dust storm event occurringon 24 April, and determined for EC, OC and inorganic ions. During thenon-dust storm period particles, EC, OC and ions except for SO42−were 2–10 times more abundant at Mt. Tai than at Mt. Hua. SO42− (13 ± 7.1 μg m−3) at Mt. Hua was the dominant ion,followed by NO3− (5.0 ± 3.9 μg m−3),NH4+ (2.5 ± 1.3 μg m−3) and Ca2+ (1.6 ± 0.8 μg m−3). In contrast, at Mt. Tai NO3− was mostabundant (20 ± 14 μg m−3), followed by SO42−(16 ± 13 μg m−3), NH4+ (12 ± 8.9 μg m−3) and Ca2+ (3.9 ± 2.1 μg m−3). Thefact of NO3− exceeding over SO42− at Mt. Tai may suggestthe changes in chemical composition of the atmosphere over east China due tosharply increasing vehicle emission. pH values of the water-extracts ofPM10 samples indicate that at the two mountain sites aerosolstransported from the south regions are more acidic than those from the northand more acidic at Mt. Tai than at Mt. Hua during the non-dust storm period.During the dust storm event particle mass, OC, Na+, K+, Mg2+and Ca2+ at both sites increased by a factor of 1–9, while EC,NO3− and NH4+ decreased by 20–80 %. However,SO42− concentrations (13 ± 7.7 μg m−3 at Mt. Hua and 15 ± 5.6 μg m−3 at Mt. Tai, respectively) at the twosites during the episode were comparable and did not change significantlycompared to those in the non-dust storm period, probably due to a similarlevel of free tropospheric SO2 in central and east China. Compared with those at Mt. Hua the coarse modes (>2.1 μm) of K+ andSO42− at Mt. Tai during the non-event period were more abundantand the coarse mode of NO3− was less abundant. When the dust stormwas present all ions significantly moved toward coarse particles, except forNH4+, with a disappeared peak in fine mode (<2.1 μm) for NO3−.Linear regression for ion equivalents in fine particles indicates thatammonium exists in the forms of NH4NO3 and NH4HSO4 atMt. Hua and NH4NO3 and (NH4)2SO4 at Mt. Tai duringboth the nonevent and the event periods. While the regression for coarsemode of Ca2+ suggests a close coupling of dust with nitrate during thenonevent time and with sulfate during the dust-storm period. pH values ofthe size-resolved samples further suggest that during the nonevent periodmost acidic particles at Mt. Hua are in the range of 0.7–1.1 μm, whilethose at Mt. Tai are in the range of 1.1–2.1 μm. Aerosols at both sitesbecame alkaline during the event, but the Mt. Tai particles still showed alower pH value

Observation of atmospheric aerosols at Mt. Hua and Mt. Tai in central and east China during spring 2009 – Part 1: EC, OC and inorganic ions