Browsing by Author "Gu, Y."

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    Molecular simulation of benzene adsorption on different activated carbon under different temperatures
    (ELSEVIER, 2020) Li, S.; Song, K.; Zhao, D.; Rugarabamu, J. R.; Diao, R.; Gu, Y.
    Four different structure models of activated carbon were constructed here by molecular simulation method. The four models include three Detecting community structure via the maximal sub-graphs and belonging degrees in complex networks with micropore sizes of 9–11 Å, 10–12 Å, and 13–16 Å, respectively, and one microporous-mesoporous structure with pore sizes of 15–17 Å and 21–24 Å. The microporous-mesoporous structure was easily adjusted by the introduction and deletion of single-wall carbon nanotubes (SWCNTs, 15, 15). The adsorption of benzene on different structure models at temperatures of 273.15, 288.15, 303.15 and 318.15 K were studied by Grand Canonical Monte Carlo (GCMC) and Molecular Dynamics (MD) methods. Adsorption isotherms, average isosteric heats of benzene adsorption, porosity and pore volume change after benzene adsorption at different temperatures were analyzed. The radial distribution function, relative concentration distributions and diffusion coefficients of benzene molecules on different structure models were further studied. Comprehensive analysis results indicate that for low temperature, activated carbon with larger micropores and mesopores is favorable to adsorption of benzene. But for high temperature, activated carbon with smaller micropores is favorable to adsorption of benzene.
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    Vegetation types and climate conditions reflected by the modern phytolith assemblages in the subalpine Dalaoling Forest Reserve, central China
    (Springer, 2015) Traoré, D. D.; Gu, Y.; Shemsanga, C.; Ge, J.; Liu, H.
    This research describes modern phytolith records and distributions from subalpine surface soils in the Dalaoling Forest Reserve, and reveals its implications for local climate conditions with respect to the altitude gradient. Well-preserved phytolith morpho-types, assemblages, and climatic indices were used to study the relationship between local vegetation and climate conditions. The phytolith classification system is mainly based on the characteristics of detailed morpho-types described for anatomical terms, which are divided into seven groups: long cells, short cells, bulliform cells, hair cells, pteridophyte type, broad-leaved type, and gymnosperm type. Phytoliths originating from the Poaceae are composed of Pooideae (rondel and trapeziform), Panicoideae (bilobate, cross, and polylobate), Chloridoideae (short/square saddle), and Bambusoideae (oblong concave saddle). Based on the altitudinal distribution of the phytolith assemblages and the indices of aridity (Iph), climate (Ic), and tree cover density (D/P), five phytolith assemblage zones have revealed the five types of climatic conditions ranging from 1,169 m to 2,005 m in turn: warm-wet, warm-xeric to warm-mesic, warm-xeric to cool-mesic, cool-xeric, and cool-mesic to cool-xeric. The Bambusoideae, Panicoideae, and Chloridoideae are the dominant vegetation at the lower-middle of the mountains, while Pooideae is mainly distributed in the higher mountains. The close relationship between phytolith assembleages and changes of altitude gradient suggest that vegetation distribution patterns and plant ecology in the Dalaoling mountains are controlled by temperature and humidity conditions. Our results highlight the importance of phytolith records as reliable ecoclimatic indicators for vegetation ecology in subtropical regions.