The sound absorption performance of porous ceramisite is determined by its pore structure, which is mainly governed by a foaming agent and heating rate during a foaming process. By tuning the heating rate and foaming agent concentration, ceramisite with different pore structures was prepared by using flyash, cement, quick lime, and plaster as raw materials as well as ammonium acetate as a low-temperature decomposition foaming agent in this work. The phase composition, microstructure, and sound absorption performance of the prepared porous ceramisite were investigated. Results demonstrate that the apparent porosity and the pore diameter increased with the increase of foaming agent concentration, accompanied with the broadening of the pore diameter distribution. The apparent porosity is positively correlated with heating rate until the temperature is higher than 20 °C·min−1, while the pore diameter is negatively correlated. The pore diameter distribution becomes narrow as a function of the heating rate. The sound absorption performance is positively correlated with the apparent porosity. An optimal pore diameter might exist, meaning diameter sizes that are larger or smaller than the optimal diameter are not conducive to the optimization of the sound absorption performance of the overall frequency band. It was determined that the curing time was not a key factor for optimizing the pore structure.
<p>The ongoing surge of international research on Asian Climate and Tectonics enables to better assess interactions between forcing mechanisms (global climate, India-Asia collision, Tibetan Plateau growth) and paleoenvironmental changes (monsoons, aridification), land-sea distribution, surface processes, paleobiogeographic evolution and the global carbon cycle. We review here the progress of the ERC MAGIC project (Monsoons in Asia caused Greenhouse to Icehouse Change?) integrating regional geodynamic constraints, well-dated environmental / biodiversity records and climate modeling. MAGIC focuses on the Paleogene period that includes the global Greenhouse to Icehouse cooling, the early collision and plateau growth and associated regional development of monsoons and westerlies over the Proto-Paratethys sea. Our work focuses on three areas constraining Asian paleoenvironments. (1) In Myanmar, paleomagnetic results, new dating of magmatic rocks and sediments along with additional detrital geochronology and basin analysis of the Burmese subduction margin and implications for the history of India-Asia convergence. (2) Along the Northeastern Tibetan Plateau margin, the combination of multiple proxies (leaf wax stable isotope, pollen, grain size, etc&#8230;)&#160; applied to an extended lacustrine Paleogene record enables to identify precisely Asian climate changes and their consequences on ecosystems. (3) In westernmost China and Tajikistan, the proto-Paratethys sea fluctuations and the sedimentary records of Pamir tectonic evolution are now precisely dated enabling to constrain driving mechanisms and paleoenvironmental consequences. Together these results are used to constrain climate modeling experiments which permit validation of hypotheses on interactions between paleogeography, paleoenvironments and paleobiodiversity at Asian and global scales in response to long-term and short-term events.</p>
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