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Tri-block poly (lactide)-poly (ethylene glycol)-poly (lactide), diacrylated derivative and the cypermethrin-loaded microcapsule were prepared, respectively. The structure of the copolymer was characterized by1HNMR, FTIR, TGA and DSC. The microcapsules were characterized by OM(optical microscope), SEM, FTIR, TGA and DSC. The encapsulation efficiency of the microcapsules is 91.3%. The microcapsules showed good dispersity and sustained release behavior in 50% ethylene glycol aqueous solution.

In order to investigate the feasibility of using methacrylic acid (MAA)-styrene (St) copolymer as dispersants to disperse azoxystrobin particles in aqueous suspension, the adsorption kinetics, isotherm and thermodynamics of MAA-St copolymer onto azoxystrobin particle surfaces were studied by batch equilibrium experiments. The results showed that the adsorption process followed the pseudo-second-order kinetic model with the entire adsorption, adsorption rate decreased with the initial concentration of MAA-St copolymer increasing. The equilibrium data were fitted with Langmuir isotherm equation better. The thermodynamic parameters were calculated, which indicated that the adsorption was a spontaneous and exothermic process in nature, and higher temperature is not beneficial to that adsorption process.

The aerodynamic analysis to human vocal folds owns great significance on understanding the principles of voice production,clinical disease diagnosis and treatment recommendations tovoice patients. This paper provides experimental data on airflow from a fourtimes scaled physical model.The results indicate that the pressure acting on the surface of the vocal cords is changed large partly by the glottal entrance angle and the glottic radius, andbringimportant impact on the glottic airflow field. The study has potential applications on voice rehabilitation, especially the design of glottis reconstruction programs.

Lots of primary or secondary structural planes in similar soil surrounding rock are the main difference with Quaternary soil surrounding rock, but the particularity isn’t considered in the analysis of tunnel stability. The fact, which similar soil surrounding rock has most weak structural planes, is testified by engineering examples. The influence of structural plane in similar soil surrounding rock on excavation stability was analyzed through combining theory with disintegration test and numerical calculation. The research results show that there are a lot of structural planes in similar soil surrounding rock. The angle between structural planes and tunnel axes and shearing strength of structural planes control the stability of tunnel. Disintegration time of soil is shortened due to structural planes. On a certain condition, structural planes can induce local collapse in soil surrounding rock while excavating.