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Reduction and immobilization of Cr (VI) as Cr2O72- is investigated by using metakaolinite-based geopolymer complexed reductant. Without reductants, the leached Cr concentration from metakaolinite-based geopolymer containing Cr (VI) is very high. Adding reductants as FeCl2·4H2O, FeSO4·7H2O, and Na2S·9H2O respectively during geopolymerization, the leached Cr concentration is below 5 mg L-1 with high Cr immobilization rate above 99 %. By comparison with the immobilization of Cr (III), the added reductants reduced Cr (VI) to Cr (III) which can be locked successfully in the amorphous structure of geopolymer. Meanwhile, Cr (VI) initial concentration is lower than 0.7 wt. % in metakaolinite-based geopolymer, the above reductants can all meet the requirements. While for Cr (VI) initial concentration larger than 0.7 wt. %, Na2S·9H2O is more appropriate. Such a simultaneous reduction and immoboilization process enables the feasibility of using metakaolinite-based geopolymer complexed reductant to implement a one-step procedure for chromite ore processing residue cleanup.

The numerical simulation results of 12 typical fire scenarios prove that the boundary conditions of tunnel entrance exert a significant influence on the accuracy and reliability of the fire numerical simulation results in metro station. In the fire scenarios with four 400-metre-long tunnels at both ends of the platform, the fire numerical simulation result is the most accurate, but the total numerical calculation time is twice more than the other fire scenarios, due to the additional volume of the computational meshes of the 4 tunnels. In order to guarantee the accuracy and reliability of the fire numerical simulation results on the condition that the computational mesh volume and numerical calculation time have not to be increased, 18 new fire scenarios with the different width of the tunnel entrance have been designed to simulate fire smoke movement in metro station, and the results are inserted into Lagrange's Interpolation Equation, then the equivalent width coefficient ε of tunnel entrance is found to be in the range of 0.34～0.55. In consideration of the mesh cell size and evacuation safety, ε is suggested to be 0.375.

The temperature and humidity are two main environmental factors, which have influence on the life of solid propellant. Comparing with single factor aging life model, hygrothermal aging life model is more feasible, which takes temperature and humidity into consideration. In this paper two hygrothermal aging life models were established. The data of hygrothermal aging test of solid propellant was used for multiregression. According to significance analysis and comparison of two models, it was shown that two models both fit the test data well. Storage life of the solid propellant under normal condition was obtained by using the life models. The results of the research can provide reference for storage life prediction of solid propellant.

By using the theory of complex adaptive system(CAS), a searching analysis of Eco-Industrial Cluster was put forward by the strategy of control, organization and evolvement,then proved that Eco-Industrial Cluster system is a real complex adaptive system(CAS), a relevant concept model was built up, and then a dynamic simulation modeling for Eco-Industrial Cluster also constructed on SWARM platform. By researching the complexity, creativity, learning and adaptability of the system, the author was trying to build up a new theory and practice method for both programmers and managers of Eco-Industrial Clusters.

This paper aims to study the influence of aggregate shape and size on the tensile strength, compressive strength and fracture energy in mesoscopic modeling of concrete. For this purpose, several numerical models under three loading cases, uniaxial tension, uniaxial compression and bending resistance test are analyzed utilizing the software ABAQUS/Explicit. The mechanical responses and cracking behaviors well match the realistic situations of experiments. Various stress-strain curves and fracture patterns are presented and compared, which indicate that the aggregate size has very small effect on the tensile strength, compressive strength and fracture energy, and the effect of aggregate shape is a little more significant than that of the size.

The polycrystalline V2O5 films as the anode in V2O5 /LiPON /LiCoO2 lithium microbattary were prepared by RF magnetron sputtering system. The V2O5 films’ crystal structures, surface morphologies and composition were characterized and analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The microbatteries were fabricated by micro electro-mechanical system (MEMS) technology. The battery active unit area is 500μm×500μm, and the thickness of V2O5, LiPON and LiCoO2 films was estimated to be 200, 610, and 220nm, respectively. The discharge volumetric capacity is between 9.36μAhcm-2μm-1 and 9.63μAhcm-2μm-1 after 40 cycles.