Search Results (2)

Plastic films utilized as greenhouse coverings play a vital role in safeguarding plantations from diverse weather conditions like sunlight, rain, hail, and wind. It is essential for these films to preserve their properties even after extended exposure to sunlight and water, while also maintaining transparency to support the unhindered growth of plants. The purpose of the study was to compare the properties of three types of plastic films: low density polyethylene diffuse film, low density polyethylene clear film, and ethylene tetrafluoroethylene film, before and after their ageing in weather test chamber with xenon-arc light in the presence of moisture. Two distinct types of PE films were chosen based on their suitability for specific regions in Croatia, whereas ETFE film was chosen as a potential new material that is gaining popularity across various industries, including agriculture. The properties investigated were tensile properties, transmittance by spectral analysis, and viscoelastic properties by dynamic mechanical analysis. Also, untreated films and the ones exposed to artificial ageing were compared by means of Fourier-transform infrared spectroscopy, differential scanning calorimetry and thermogravimetric analysis. The administered tests revealed a certain level of property degradation due to ageing in all three films. However, none of the films showed a substantial level of deterioration, indicating their suitability as greenhouse coverings. Full article

The renovation or the functional transformation of existing stock to meet the new comfort standards and energy demand reduction often requires comparing alternative technological options and designing solutions especially when it involves historical buildings where the main goal is usually to preserve the original image and value of the building. The paper reports a study regarding the potential covering of the inner courtyard of Palazzo Poggi in Bologna with a roof to create an intermediate new space between outdoors and indoors to be used all year long. The study is particularly focused on the definition of a simplified algorithm to predict and evaluate the annual temperature trend of the court, once it has been covered, assuming some geometrical and thermal characteristics of the roof. The paper describes the calculation algorithm and its application on the Palazzo Poggi case study where a covering in EFTE (ethylen-tetrafluorethylen) membrane is supposed to be created. Full article