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The effects of different concentrations (0%–20%) of soybean oil or lard added to pomfret surimi gel on its physicochemical properties and protein structure were studied. The addition of 8% lard or soybean oil significantly increased the whiteness, water-holding capacity (WHC), gel strength, storage modulus (G’) and sensory evaluation of surimi. When the addition level was higher than 8%, the strength, WHC, and G’ decreased. Surimi gel with 8% lard was better than that with the same concentration of soybean oil. The results of scanning electron microscopy (SEM) showed that lipids not only filled the void between protein molecules, but also formed an interfacial protein film on the surface, which combined with the protein matrix through protein filaments. It was shown that there was an interaction between lipids, the interfacial protein membrane and proteins in surimi gels. Raman spectra showed that the addition of lipids decreased the relative content of α-helix, and the first increases and then decreases of β-sheet. The addition of soybean oil also significantly increased the relative content of random coils, while the change in random coils of lard was not as significant as that of the soybean oil treatment group. Both soybean oil and lard led to the exposure of hydrophobic groups on the side chain of proteins in surimi gels. These results suggest that the addition of oil changes protein structure and microenvironment in surimi, which in turn affects the physicochemical properties of surimi gels. The surimi gel with 8% lard has better properties.

One key obstacle restricting the application of fiber-reinforced polymer (FRP) bars from being used as reinforcement in structural concrete is the significantly reduced ductility because FRP under tension is linear elastic up to brittle rupture at small strain. Recently, a new structural concept, compression yielding (CY), has been proposed as a way to overcome the insufficient ductility of concrete structures reinforced with FRP bars or other non-ductile materials. In the CY structural system, the compression-zone of normal concrete is replaced by a ductile material within the plastic hinge. This enables the flexural deformation to be achieved by the compressive deformation of CY material rather than a tensile deformation of longitudinal reinforcing bars. To this end, an ideal CY material requires strength to be maintained during the extraordinarily large deformation process. This study tries to identify methods for developing this kind of CY material by designing and optimizing perforations inside a mild steel block. The effects of key parameters, including ratio, diameter, and arrangement of perforations on the stiffness, strength, and ductility of CY materials were experimentally investigated. In addition, a finite element (FE) model was developed to predict the behavior of the proposed CY material.

On one hand, the nature of linear elastic up to brittle rupture hinders the application of fiber-reinforced polymer (FRP) bars as reinforcement in the concrete member due to the displacement ductility demand of structures. On the other hand, FRP bars are equipped with many irreplaceable advantages as reinforcement in concrete structures. To resolve this contradiction, a possible solution is to use the so-called compression yield (CY) structural system and the ductility of a concrete beam incorporating a CY system comes from the compressive side rather than the tensile side. Thus, the development of material in the compressive side (CY material) with well-designed mechanical properties (strength, stiffness, and ductility) is a key challenge. In this study, the CY material is developed by perforating the mild steel block and then substantiated by the test results. Then, experimentally calibrated finite element models are used to conduct systematic parametric studies, based on which parametric equations are proposed to predict the stiffness and ultimate strength of the CY material. Finally, theoretical constitutive models are developed to predict the stress–strain response of perforated steel block under compression and a reasonably acceptable agreement is reached between the model predictions and the test results.

Improving and reusing recycled aggregate concrete (RAC) is an ideal approach to develop sustainability in the construction industry. In this article, a newly proposed physical compression casting method was used in combination with a treatment of nano-silica (NS) particles to enhance the properties of RAC. Although using NS contributed to accelerating hydration, promoting pozzolanic reaction, and increasing calcium-silicate hydrate gel, the enhancement in strength and reduction in porosity was found to be limited. Thus, the compression casting method was used to compensate for the weaknesses. The effects of compression casting, NS, and their combinations on the properties of RAC were investigated. At the macro-level, the stress–strain responses were evaluated by examining the compressive strength, peak strain, and modulus of elasticity. At the micro-level, the porosity and pore distribution along the interface transition zones (ITZs) were investigated using mercury intrusion porosimetry analysis and scanning electronic microscope imaging technology. Compared with normal RAC, the compressive strength achieved by using NS particles, compression casting, and their combination were increased by 37, 88 and 143%, respectively. The compression casting or combination of compression casting and NS particles treatment can effectively reduce the total porosity of the mortar and pore ratio along the ITZs.

The overuse of antibiotics has led to severe environmental pollution, thereby making it increasingly important to efficiently degrade them. To address this, a unique S-scheme heterojunction of the In2S3/In2O3 nanocomposite was successfully constructed using hydrothermal coupled with in situ formation in this work. The optimized In2S3/In2O3 nanocomposite exhibited a significant photocatalytic degradation of tetracycline (TC), achieving an 83% removal rate within 60 min, with enhancements of 1.78 times for In2S3 and 1.66 times for In2O3. Characterization, experimental results, and density functional theory (DFT) calculation collectively prove the efficient transfer of photoexcited carriers between In2O3 and In2S3, coupled with the successful construction of the S-scheme heterojunction with a well-arranged band structure. A potential pathway for developing photocatalysts with exceptional antibiotic removal capabilities has been provided by enhancing their reduction and oxidation capabilities of the S-scheme heterojunction through rational structural configuration. [ABSTRACT FROM AUTHOR]