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The substitution of river sand with glass aggregate (GA) and cement with glass powder (GP) is a mainstream method to recycle waste glass. Traditionally, standard curing was widely used for glass-based mortars. However, it is time-consuming and cannot address low mechanical strengths of the early-age mortars. Therefore, the effect of water curing at 80 °C on the properties of GA mortars is investigated. Furthermore, the effect of the GP size is also considered. Results show that compared with the expansion of alkali-silica reaction (ASR), water curing at 80 °C has a negligible effect on the volume change. Moreover, the compressive strength of GA mortars under 1-day water curing at 80 °C is comparable with that under 28-day water curing at 20 °C. Therefore, the 1-day water curing at 80 °C is proposed as an accelerated curing method for GA mortars. On the other hand, the addition of GP with the mean size of 28.3 and 47.9 µm can effectively mitigate the ASR expansion of GA mortars. Compared with the size of 28.3 µm, GA mortars containing GP (47.9 µm) always obtain higher compressive strength. In particular, when applying the 1-day water curing at 80 °C, GA mortars containing GP (47.9 µm) can even gain higher strength than those containing fly ash.

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Ultrasonic curing is an effective way to enhance the curing extent of composite material bonding in the aerospace industry. The non-thermal effect of ultrasonic has been revealed to improve curing efficiency. However, the mechanism of the ultrasonic non-thermal effect is still not clear. In this work, a variable activation energy model of ultrasonic curing was established by utilizing the iso-conversional method, including the activation energy of the thermal effect and activation energy of the non-thermal effect. The thermal effect caused by ultrasonic was accurately peeled off. An obvious decrease in activation energy was found from 54 kJ/mol in thermal curing to 38 kJ/mol in ultrasonic curing. The activation energy of the reaction system in ultrasonic curing was substituted into the modified Kamal autocatalytic equation, and the parameters of the ultrasonic curing kinetic model were estimated by means of an ALO algorithm. Further discussion based on in situ FTIR showed that the non-thermal effect of ultrasonic can affect the vibration strength, stability, and chemical bond energy of internal groups, but cannot cause the fracture of chemical bonds. Moreover, frontier molecular orbital analysis showed that the chemical reactivity of epoxy/amine molecules increased and the HOMO-LUMO energy gap decreased from 6.511 eV to 5.617 eV under the effect of ultrasonic.

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A resorcinol-dialdehyde starch-formaldehyde (RDSF) copolycondensation resin adhesive was prepared by substituting high reactive dialdehyde starch for a portion of formaldehyde in the formulation. Fourier transforms infrared spectrometer (FTIR) analysis results confirmed that the copolycondensation reaction of the dialdehyde starch with resorcinol and formaldehyde was successful. The curing property, thermal stability, permeability and crystal structure of the RDSF adhesive were characterized using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), scanning electron microscope (SEM), X-ray diffraction (XRD). The solids content, viscosity, curing time, bonding strength were also obtained. The results showed that the RDSF adhesive had a higher solids content, moderate viscosity, shorter curing time and better bond strength than a standard resorcinol-starch-formaldehyde (RSF) adhesive. It was found that dialdehyde starch could accelerate the curing rate, while decreasing the curing temperature and heat release during the curing process of RDSF. The dense cross-linked structure of the dialdehyde starch and resorcinol-formaldehyde (RF) system produced improved thermal stability. SEM results showed that the RDSF adhesive formed a thin and continuous adhesive layer on the surface of a poplar board, and filled the pores of the wood, which improved the bond strength. The crystal structure of the RDSF was not altered by addition of the starch, and the physicochemical properties of the adhesive were similar to those of a normal resorcinol-formaldehyde resin.

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Pulsed electric field (PEF) is a novel non-thermal technology that has recently attracted the attention of meat scientists and technologists due to its ability to modify membrane structure and enhance mass transfer. Several studies have confirmed the potential of pulsed electric field for improving meat tenderness in both pre-rigor and post-rigor muscles during aging. However, there is a high degree of variability between studies and the underlying mechanisms are not clearly understood. While some studies have suggested physical disruption as the main cause of PEF induced tenderness, enzymatic nature of the tenderization seems to be the most plausible mechanism. Several studies have suggested the potential of PEF to mediate the tenderization process due to its membrane altering properties causing early release of calcium ions and early activation of the calpain proteases. However, experimental research is yet to confirm this postulation. Recent studies have also reported increased post-mortem proteolysis in PEF treated muscles during aging. PEF has also been reported to accelerate curing, enhance drying and reduce the numbers of both pathogens and spoilage organisms in meat, although that demands intense processing conditions. While tenderization, meat safety and accelerated curing appears to be the areas where PEF could provide attractive options in meat processing, further research is required before the application of PEF becomes a commercial reality in the meat industry. It needs to deal with carcasses which vary biochemically and in composition (muscle, fat, and bones). This review critically evaluates the published reports on the topic with the aim of reaching a clear understanding of the possible applications of PEF in the meat sector in addition to providing some insight on critical issues that need to be addressed for the technology to be a practical option for the meat industry.

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A model that describes hydration and heat-mass transport in Portland cement mortar during steam curing was developed. The hydration reactions are described by a maturity function that uses the equivalent age concept, coupled to a heat and mass balance. The thermal conductivity and specific heat of mortar with water-to-cement mass ratio of 0.30 was measured during hydration, using the Transient Plane Source method. The parameters for the maturity equation and the activation energy were obtained by isothermal calorimetry at 23 °C and 38 °C. Steam curing and semi-adiabatic experiments were carried out to obtain the temperature evolution and moisture profiles were assessed by magnetic resonance imaging. Three specimen geometries were simulated and the results were compared with experimental data. Comparisons of temperature had maximum residuals of 2.5 °C and 5 °C for semi-adiabatic and steam curing conditions, respectively. The model correctly predicts the evaporable water distribution obtained by magnetic resonance imaging.