Abstract: Polycrystalline Ca3-xMgxCo4O9（x=0-0.3）ceramics were prepared by the sol–gel method combined with the ordinary pressing sintering and the thermal conductivities were measured from room temperature to 673 K. The influence of Mg2+ substitution for Ca2+ on the thermal conductivities of Ca3Co4O9 ceramics was investigated systematically. The influence of Mg doping on the thermal conductivities is mainly embodied in the lattice thermal conductivities, which shows a significant decrease with the increase of the dopant content for the samples with x ≤ 0.2, while the carrier thermal conductivity had no obvious change with Mg doping increasing. These results indicated that the thermal conductivities of the material could be reduced remarkably with the substitution of Mg from 1.427 W/m·K to 0.731 W/m·K at 573 K with x = 0.2.
Abstract: The deficiency of bond capacity of traditional cement mortar was exposed as the new wall materials were used widely. The polyvinyl-butyral(PVB) and methyl cellulose(MC) were chosen as chemical additives to amend the property of normal mortar, the orthogonal tests of 96 pieces of shear specimens were carried out, and the orthogonal analysis of test results was performed. The results indicated that the sort of wall material was the most important factor in bond capacity of mortar, the mixed quantity of polymer and mortar strength follows, and there was a remarkable increase in mortar bond strength when the mixed quantity of PVB and MC was 20%~30% and 0.05%~0.1% respectively.
Abstract: Building materials for decoration are carriers for space art design to represent language, are material foundation for environment art design. Selection of materials is the basic matter for study of design. So, only by getting a full understanding of the properties of decoration materials, making good use of their advantages through reasonable selection and flexible collocation, and with respect to the available space environment, can materials perfectly perform their functions, thus fulfill the demand of interior space design. Art design and materials are interactional. The realization of art design depends upon materials and materials can get life with excellent design. By starting from the use of physical appearance of materials, we can dig out interior decoration materials’ potentialities for originality, and break through traditional way of design expression, and set up new concepts about how to use decoration materials.
Abstract: Titanium oxide coatings(TiO2/Ti) were formed on the titanium surface by micro-arc oxidation(MAO) in Na3PO4 solution.And using the TiO2/Ti as anod electrode, the titanium as counter electrode in the system of three-dimensional electrode.Coated γ- Al2O3 (TiO2/γ-Al2O3) that prepared by sol-gel dipcoating method ,and scrap iron mixture as particle electrode, combining with the UV lamp and regulated power supply make up the three-dimensional electrode photoelectrocatalysis system. The photoelectrocatalysis system use 0.02M Na2SO4 aqueous solution as supporting electrolyte.The photoelectrocatalytic ability of titanium oxide coatings were evaluated by photoelectrocatalytic degradation of methylene blue aqueous solution.The experiment demonstrate that compare to photoelectrocatalytic degradation of single TiO2/Ti film and only adsorbtion, the photoelectrocatalysis of three-dimensional electrode with coated particle electrode have the synergistic effect with them, which can improve the degradation of methylene blue aqueous solution. When the methylthionine chloride concentration of 5mg/L, cell voltage of 7V. The three-dimensional electrode photoelectrocatalysis degradation of methylene blue compare to traditional two-dimensional plate electrodes which without particle electrode increase 43.35% after 3 hours photoelectrocatalysis.
Abstract: The heat transfer coefficients of two foam glass exterior thermal insulation walls were tested by weather-resistant testing instrument and heat flow meter. The experimental values were compared with the theoretical values. The results show that with the temperature differences Δt>20 °C, the testing errors of two walls are smaller than 1% and 3% respectively. In view of thermal performance, testing accuracy and operability, the test program is practicable to meet the testing requirement with a temperature difference greater than 20 °C and without seasonal restrictions. In the zones without heating such as hot summer and cold winter zone, therefore, the weather-resistant testing instrument (i.e. temperature control box) and heat flow meter can be used to test the heat transfer coefficient of a wall.
Abstract: Based on the experiments on 10 specimens of steel fiber reinforced high strength concrete three-pile caps with the ratio of the model to the real of 1:5, the developing of cracks and failure of caps were described, the transfer mechanism of pile caps was analyzed in detail and the principle of space truss model of the thick three-pile cap was proposed. The test results suggested that the destruction of thick pile cap belongs to punching or shear failure, which is different from that of the general bending member.
Abstract: To study flexural performance of one-way slabs externally prestressed with GFRP tendons, a series of experiments were carried out. Based on the results, the load-deflection responses and bending capacities were presented in this paper. Moreover, the influence factors, including the quantity of GFRP tendons and prestressing force, were discussed. Comparison tests proved that the slabs externally prestressed with GFRP tendons will be improved in some aspects, such as ultimate deflection, flexural stiffness, bending capacity, larger deformation before failure.
Abstract: Through the seismic behavior of 4 pieces of concrete grill wall by pseudo- static test, the test sample destruction shape, the skeleton curves under to the different wall material and the different axial compression ratio, consuming energy ability, the ductility coefficient were conducted the contrast research. The experiment indicates the test sample under the level reciprocation load and the axial action of force, destruction shape main perform for cutting destruction; After wall dehiscence, the rigidity rate of descent is quick, after achieving the ultimate load, the rigidity drop flatten out, the wall has the good ductility. By enhancing the axial compression ratio, it may enhance the wall the ductility, to consume energy the coefficient; the walls contained recycled concrete aggregate has good energy dissipation and seismic performance;
Abstract: Building material industry can absorb lots of scrap of chemical industry, metallurgical industry and coal industry. Through our further study on the application of cyclic economy in the building materials industry, we initially summarize the co-production models between building materials industry and other industries, such as coal, metallurgy and mining, based on the recycling economy. The models also represent the basic patterns which can recycle mineral resources and reuse energy efficially. We advice some possible countermeasures though analysis of the domestic application of these models in the current problems and challenges.
Abstract: Organic precursor of EP/PU was prepared by epoxy resin which was polyurethane toughened, and then modified epoxy resin adhesive was synthesized using nano-silica as modifier. Microstructure of composite materials was observed by scanning electron microscopy (SEM), the results showed that the inorganic phase had good compatibility in polymer matrix, and polyurethane in epoxy resin have formed the "island structure". The mechanical properties, thermal stability and dielectric loss, dielectric constant of composites were investigated. The results indicated that doping of appropriate amount of nano-silica could improve mechanical property, shear strength and impact strength of 2wt% SiO2/EP-PU were increased 173% and 106.67%, than that of pre-doping of composite, respectively. Thermal decomposition temperature (Td) was increased, Td of 2wt%SiO2/EP-PU was increased 8.1°C than that of pre-doped of material. Dielectric constant (ε) was as follows: was decreased with the increase of frequency, but increased with the increase of inorganic component, dielectric loss (tanδ) was increased with the increase of frequency and inorganic doping.