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Polyethylene glycol (PEG) particles were prepared using low-temperature supercritical assisted atomization (LTSAA) with carbon dioxide as the spraying medium or the co-solute and acetone as the solvent. The effects of several key factors on the particle size were investigated. These factors included the concentration of the PEG solution, precipitator temperature, saturator temperature, ratio of the volumetric flow rate of carbon dioxide to the PEG solution, and the molecular weight of PEG. Spherical and non-aggregated PEG particles, with a mean size of 1.7–3.2 µm, were obtained in this study. The optimal conditions to produce fine particles were found to be a low concentration of the PEG solution, a low precipitator temperature, and low molecular weight of the PEG. The phase behavior of the solution mixture in the saturator presented a qualitative relationship. At the optimized volumetric flow rate ratios, the composition of CO2 in the feed streams was near the bubble points of the saturator temperatures. X-ray and differential scanning calorimetry analyses indicated that LTSAA-treated PEG had a reduced degree of crystallinity, which could be modulated via the precipitator temperature. PEG microparticles prepared by a LTSAA process would be promising carriers for drug-controlled formulations of PEG-drug composite particles.

Sponge-related research in Taiwan has primarily focused on natural product exploration. This research has, however, been hampered by a lack of fundamental work on sponge taxonomy and ecology. In the present study, subtidal sponges were photo-recordedin situand collected by scuba diving at a depth range of 2–20 m from 2009 to 2012 in 16 different sites surrounding the Penghu Archipelago, Taiwan. Sponge samples were identified to the lowest taxonomic level based on skeletal morphology and spicules. A total of 53 species belonging to 24 families and 10 orders were identified in this study. The number of sponge species per site ranged from 0 to 24. The most widely distributed sponge species wasCallyspongia(Euplacella) cf.communis(Carter, 1881) followed byHaliclona(Gellius)cymaeformis(Esper, 1794), andAaptos suberitoides(Brøndsted, 1934). At one location, Chipeiyu, no sponges were observed. Non-metric multidimensional scaling (NMDS) ordination revealed relatively low similarity among most sampling sites. Large- and small-scale hydrological and habitat features are probably responsible for compositional variation of sponge assemblages among groups of sampling sites. Our richness analyses suggest that many more sponge species remain to be discovered in the Penghu Archipelago.