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The binary blend materials containing the modified recycled rubber powder with maleic a hydride modified polypropylene thermoplastic elastomer were prepared by dynamic vulcanization and blended with a variety of additives such as activated agent, accelerator, solubilizer, and the crosslinking agent. The thermal properties and mechanical properties including tensile strengths and impact strengths of pristine rubber, polypropylene and their corresponding binary blends were investigated. Besides, the effects of the amount of rubber powder, polypropylene, crosslinking agent, accelerator, activator, and solvent were studied and the microstructures of the pristine rubber, pristine polypropylene, and their corresponding binary blends were observed by scanning electron microscopy. It was found that the compatibilizer could effectively disperse the size of 120 mesh of recycled rubber powder into the polypropylene in the same manner and the homogeneous tear section of the rubber/polypropylene thermoplastic elastomer was obtained. The results on the effects of additives on mechanical and morphological properties of recycled rubber/polypropylene binary blends guide the rational design of novel polymeric composites from recycled polymeric materials. [ABSTRACT FROM AUTHOR]

Button mushroom (Agaricus bisporus) slices were dehydrated using ultrasound-assisted osmotic dehydration (UOD), and three osmotic agents including sucrose, glucose and sodium chloride were investigated for their effects on the mass transfer characteristics, average density and microstructure. Different mathematical models were selected to describe the osmotic behaviours, and the effective moisture (Dm) as well as solid diffusivities (Ds) during UOD were also calculated. The results showed that, during UOD, button mushrooms had the highest Dm values in the sodium chloride solutions, and they had the highest Ds values in the glucose solutions, which indicated that faster moisture and solid transfers could occur in these two osmotic solutions, respectively. Moreover, the Weibull model provided the best fit for the UOD curves of button mushrooms under the study's operating conditions, which showed good predictability for the moisture and solid contents of the button mushrooms during UOD. In addition, sucrose agents were suggested for use in the UOD of button mushrooms due to the better microstructure of the products as well as the appropriate rates of effective moisture and solid diffusivities during UOD. This study provides a theoretical basis for the deep processing of mushrooms and other food products. [ABSTRACT FROM AUTHOR]

The microstructure-property relation in ferroelectric/ferromagnetic composite is investigated in detail, exemplified by typical sol-gel-derived 0.3BTO/0.7NZFO ceramic composite. The effect of microstructural factors including intergrain connectivity, grain size and interfaces on the dielectric and magnetic properties of the composite prepared by conventional ceramic method and three-step sintering method is discussed both experimentally and theoretically. It reveals that the dielectric behavior of the composite is controlled by a hybrid dielectric process that combines the contribution of Debye-like dipoles and Maxwell-Wagner (M-W or interfacial) polarization. Enhanced dielectric, magnetic and conductive behaviors appear in the composite with better intergrain connectivity and larger grain size derived by sol-gel route and three-step sintering method. The effective permittivity contributed by Debye-like dipoles exhibits a value of ~130,000 in three-step sintered composite, which is almost the same as that in conventionally sintered one, but that contributed by M-W response is much smaller in the former. Compared with conventionally prepared samples, the relaxation time ( τ) is 3.476 × 10 s, about one order of magnitude smaller, and the dc electrical conductivity is 3.890 × 10 S/m, one order of magnitude higher in three-step sintered composite. The minimum dielectric loss reveals almost the same (~0.2) for all samples, but shows distinguishable difference in low-frequency region. Meanwhile, an initial permeability of 84, twice as large as that of conventionally prepared composite and 56 % the value of single-phased NZFO ferrite (~150), and a saturation magnetization of 63.5 emu/g, 32 % higher than that of conventional one and approximately 84 % the value of single-phased NZFO ferrite (~76 emu/g), appear simultaneously in three-step sintered composite with larger grain size and better intergrain connectivity. It is clear that the discovery is helpful for establishing a more explicit view on the physics of multi-functional composite materials, while the composite with optimized microstructure is beneficial to be used as a high-performance material. [ABSTRACT FROM AUTHOR]

Freeze-drying (FD) and three different combinations of drying methods: freeze-drying combined with hot air drying (FD + AD), freeze-drying combined with vacuum drying (FD + VD) and freeze-drying combined with microwave vacuum drying (FD + MVD) were used to dry button mushroom slices. A comprehensive analysis of dried products was performed on their colour, texture, nutrient retention, microstructure and energy consumption. The results showed that, under conditions of 38 % moisture content changing point, most of the parameters including L* values, a* values, average density and hardness of FD + VD and FD + MVD samples had no remarkable changes ( p > 0.05) compared with FD samples. However, only FD + MVD method can reduce drying time by 35.63 % in comparison of FD method, although all the combination drying methods can reduce the energy consumption. Moreover, FD + VD and FD + MVD products were better than FD + AD products in nutrient retention except that content of vitamin C was comparatively lower during FD + MVD process. In conclusion, the FD + MVD method has advantages in terms of efficiency and energy saving and could be preferred to produce high-quality products. [ABSTRACT FROM AUTHOR]