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Thermal comfort and energy saving have become a priority for construction industry professionals. An important parameter of the comfort is the mean radiant temperature and its dependence on the building envelope. In the present research, a dynamic physical model has been studied in a climatic chamber, linked to the specific heat (C), density (r) and thermal conductivity (l). The heat capacity is usually quantifiable in small, homogeneous and uniform samples by the application of calorimetric methods. Consequently, the building energy consumption assessed through calorimetric methods, is often quite different from the energy consumption measured in situ. In this work an experimental model for the assessment of specific heat of real-size building components is proposed. Such a parameter was determined by measuring the heat flow through a building wall. The model has been validated by comparing the evaluated properties of known materials for different thermal gaps.

Carbon dioxide and methane emissions are major greenhouse gases contributing to global warming, thus calling for rapid techniques of sequestration. For instance, dry reforming of methane transforms CO2 and CH4 into syngas, a mixture of H2 and CO, yet the reaction catalyst becomes inactivated by carbon formation and metal sintering. Here, we review catalytic systems used for dry reforming of methane. Improved catalysts of high catalytic performance and stability are obtained by selecting the active metal, supporting materials, promoters and preparation techniques. We found a strong correlation between the support morphology, physicochemical properties and catalytic performances. In particular, fibrous structures show optimal metal–support interaction, distribution, particle size, basicity, storage of oxygen space, surface area and porosity, resulting in high performance of anti-coking and anti-sintering. [ABSTRACT FROM AUTHOR]

Thermal comfort and energy saving have become a priority for construction industry professionals. An important parameter of the comfort is the mean radiant temperature and its dependence on the building envelope. In the present research, a dynamic physical model has been studied in a climatic chamber, linked to the specific heat (C), density (λ) and thermal conductivity (λ). The heat capacity is usually quantifiable in small, homogeneous and uniform samples by the application of calorimetric methods. Consequently, the building energy consumption assessed through calorimetric methods, is often quite different from the energy consumption measured in situ. In this work an experimental model for the assessment of specific heat of real-size building components is proposed. Such a parameter was determined by measuring the heat flow through a building wall. The model has been validated by comparing the evaluated properties of known materials for different thermal gaps. [ABSTRACT FROM AUTHOR]