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Glazing units are indispensable for a variety of buildings and their thermal behavior has significant effects on improving indoor thermal comfort and decreasing energy consumption. Recently, the double glazed windows that are filled with phase change material (PCM) have been considered as potential glazing units. Therefore, the dynamic thermal behavior of the PCM-filled double glazing unit is investigated in this work. A three-layer glass-PCM-glass model considering coupled conduction-solar radiationphase change is established. Effects of physical parameters of the PCM on the thermal behavior of the PCM-filled glazing unit are examined thoroughly. The results indicate that the filling of PCM can affect heat transfer within the glazing unit significantly by reducing solar energy entering the indoor room through the window. When the glass-PCM-glass model is adopted, the transmitted solar energy can be reduced by 78.82 W/m2. Optical parameters (especially absorption coefficient) of the PCM have significant impact on the thermal behavior of glazing units: the larger the absorption coefficient is, the less solar energy will enter indoors, and the larger will be the temperature fluctuation. For different absorption coefficients, the maximum temperature difference on the interior surface can reach 3.57°C. Thermal properties of the PCM also have significant impact on the thermal behavior of glazing units. Decreasing the thermal conductivity or increasing the latent heat of the PCM can reduce the temperature fluctuation of the glazing windows. Selecting a reasonable melting temperature can make full use of the heat storage capacity of PCM. Thus, this study can provide a reference for how to apply PCM into a transparent envelope in buildings. [ABSTRACT FROM AUTHOR]

Drying kinetics, color, and texture changes in different drying temperatures of jujubes were investigated in this study. With the increase of temperature, the drying time reached a minimum (140 min) at 80℃. At the temperature of 40℃, the retention of the original color was the greatest (ΔE = 1.66); similar results were also reflected by the measured pulp browning (4.186 ± 0.350 Abs/g) and 5-HMF (0.517 ± 0.044 mg/g). After drying, the fruit hardness decreased to 55.91%–86.59% of the initial (2,543.2 ± 181.4 g). SEM showed that the HAD temperature exceeded 60℃ and the pulp tissue sharp dramatically, causing the fruit to harden. Affected by drying temperature and polygalacturonase, WSP increased in drying, whereas CSP and NSP showed the opposite trend, and they were significantly correlated with the texture of fruits. The results expanded our understanding of the jujube drying process and provided guidance for controlling the quality of jujube during HAD processing. Practical applications The drying method of jujube fruit in China is special, which is a combination of air drying and hot air drying. However, discoloration, shrinkage, and other quality deterioration occurred during the drying process, significantly affecting the quality of jujube fruit. In this study, semi-air-dried jujubes were used to investigate the color and texture during hot air drying. These results will provide valuable information to the pilot or industrial scale processors and also served as an operational guide for the jujube fruit drying process. [ABSTRACT FROM AUTHOR]