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Thermo physical behavior of metakaolin-based geopolymer materials was investigated. Five compositions of geopolymers were prepared with Si/Al from 1.23 to 2.42 using mix of sodium and potassium hydroxide (~7.5 M) as well as sodium silicate as activator. The products obtained were characterized after complete curing to constant weight at room temperature. The thermal diffusivity (2.5-4.5 × 10-7m2/s) and thermal conductivity (0.30-0.59 W/m K) were compared to that of existing insulating structural materials. The correlation between the thermal conductivity and parameters as porosity, pore size distribution, matrix strengthening, and microstructure was complex to define. However, the structure of the geopolymer matrix, typical porous amorphous network force conduction heat flux to travel through very tortuous routes consisting of a multiple of neighboring polysialate particles

A new incentive scheme for power generation from biogas is favoring in Italy the construction of small plants. These ones, however, have poorer financial viability and biological stability than larger plants. In order to ensure adequate performance and a reasonable payback period it is therefore essential that every aspect of their operations is carefully designed. In this respect, summer overheating of anaerobic digesters due to solar gains must be prevented. A solution relies upon the implementation of a ‘cool’ gasometer dome with properly chosen solar reflectance, whose effectiveness was assessed through the use of a calculation code specifically built and validated by comparison with experimental data

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