This study has demonstrated the height variation and layout of urban architecture affect the local concentration distribution of particulate matter (PM) in the atmosphere and for the first time that wind velocity has particular effects on PM transport in various building groups. The findings may have general implications in optimization the building layout based on particle transport characteristics during the renewal of industrial cities. For city planners, the results and conclusions are useful for improving the local air quality. The study method also can be used to calculate the explosion risk of industrial dust for people who live in industrial cities.

Hyperbranched poly(3-ethyl-3-(hydroxymethyl)oxetane) (HPBO), modified by S-1-dodecyl-S -(α,α -dimethyl-α -acetic acid) trithiocarbonate (DMP) to form a RAFT macroinitiator, and then two monomers, 2-(dimethylamino)ethyl-methacrylate (DMAEMA) and acrylic acid (AA), were polymerized to obtain novel pH-and thermo-sensitive polymers with a hyperbranched polymer core. These polymers exhibited phase transitions in response to pH and temperature. They were possible to harvest a bioactive molecule, indometacin, from solution using the phase transition of these pH-and thermo-sensitive polymers. Various parameters, such as percent loading of drugs, pH, temperature and nature of the release media on the release profiles, were investigated. The resultant polymer carriers can potentially be used for the controlled release of the anti-inflammatory drug indometacin.

In the paper, the chitooligosaccharide (CHO) was surface-grafted on the medical segmented poly(ester-urethane) (SPU) film by a facile two-step procedure to improve the surface biocompatibility. By chemical treatment of SPU film with hexamethylene diisocyanate under mild reaction condition, free -NCO groups were first introduced on the surface with high grafting density, which were then coupled with -NH2 groups of CHO to immobilize CHO on the SPU surface (SPU-CHO). The CHO-covered surface was characterized by FT-IR and water contact angle test. Due to the hydrophilicity of CHO, the SPU-CHO possessed higher surface hydrophilicity and faster hydrolytic degradation rate than blank SPU. The almost overlapping stress-strain curves of SPU and SPU-CHO films demonstrated that the chemical treatments had little destruction on the intrinsic properties of the substrate. In addition, the significant inhibition of platelet adhesion and protein adsorption on CHO-covered surface endowed SPU-CHO an outstanding surface biocompatibility (especially blood compatibility). These results indicated that the CHO-grafted SPU was a promising candidate as blood-contacting biomaterial for biomedical applications.

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