The effectiveness of low-emissivity coating on a polymer film
This work describes the effectiveness of low-emissivity (low-E) coating on the polymer film with TiO2/ZnO:Ga/Ag/ZnO:Ga/TiO2 structure and the results of heat monitoring. The characteristics of the coating which determine the reduction of heat loss by the low-E coating are given. Also the results of efficiency calculations for low-E coating are presented, such as resistance to heat transfer, heat savings when installing low-E coating on the polymer film, etc. The heat monitoring is carried out to determine the effectiveness of low-E coating. The results of heat monitoring illustrate the effectiveness of low-E coating.
Durability of Ag based low‐emissivity coatings
Films of ZnO/Ag/Sn/ZnO deposited by dc magnetron sputtering are being widely used as ‘‘heat mirror’’ films in architectural applications. The long‐term durability of these films has been studied through accelerated weathering and exposure to controlled atmospheres of C12, H2S, and moisture. After accelerated exposure, films were analyzed by ultraviolet–visible–near infrared and far infrared spectroscopy, Auger depth profiling, and scanning electron microscopy. No significant changes were seen in transmittance or infrared reflectivity. No interdiffusion of layers was seen in Auger profiling.
Experimental investigation of the geotechnical properties and microstructure of lime-stabilized saline soils under freeze-thaw cycling
Abstract The Song-Nen Plain in northeastern China holds one of the three largest expanses of soda saline-alkali soil in the world. Due to its disadvantageous geotechnical properties, the saline soil in this area is unable to meet the needs of construction projects. This study evaluates the stabilizing effect of adding lime to such soils. Specifically, it investigates how the physicochemical and mechanical properties and microstructure of soda saline-alkali soil are altered by lime and how these changes are affected by both freeze-thaw cycling and the duration of curing. The results reveal that adding lime to saline soil transforms clay particles into sand and silt particles and causes the pore size distribution (PSD) to become bimodal, with small-pore and macropore populations. An increase in lime content leads to an increase in the unconfined compressive strength (UCS) but a gradual decrease in both the cation exchange capacity (CEC) and plastic index. Freeze-thaw cycles break up coarse particles and aggregate finer particles, increasing the diameter of macropores and decreasing the USC; however, the effect on specimens with >9% lime is negligible. It is further shown that the geotechnical properties of the soil change immediately after the addition of lime, indicating that the cation exchange reaction takes place very quickly. Furthermore, the pozzolanic reaction leads to an increase in the percentage of sand-sized particles and a decrease in porosity after 28 days of curing. Overall, these results indicate that it is feasible to use lime to improve the engineering properties of soda saline-alkali soil in this area.