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In recent years, closed circulating water systems in heat exchangers have been developing continuously. During the high-temperature heat exchange process in summer, the external spray system can easily cause scaling and corrosion of the heat exchanger. In order to study the factors affecting the scaling and corrosion of the heat exchanger under different pH and spray conditions of the spray working solution, the experimental methods such as immersion experiments and interval titration methods were designed to simulate the actual working environment. Moreover, the scaling mechanism of the heat exchanger was further clarified through characterization methods such as sample microsurface morphology, mass changes, and electrochemical performance tests. Results showed that under the short-cycle heating titration experiment, the simulated solution with pH=5 was prone to react in a dynamic environment and was prone to scaling in the flat tube. Under the immersion experiment and the long-cycle heating titration experiment, the simulated solution was in the relatively static condition, and the experimental samples were not easy to be scaled. In general, this work enriched the related research on plate heat exchanger fouling and provided a strong basis for future plate heat exchanger fouling and corrosion protection.

In order to explore the composition, pH and concentration changes of the antifouling agent zinc pyrithione (ZPT) during the service process of zinc pyrithione-containing self-polishing antifouling coating (ZPT-SPC), and clarify the antifouling mechanism of ZPT-SPC during service, SEM/EDS were employed to explore the changes in cross-sectional micromorphology and composition of coatings before and after polishing. Moreover, the open circuit potential-pH experiment was used to measure the changes in the micro-potential-pH information of paint scratches. The changes in ZPT composition and content on the paint surface during service were explored through Raman spectroscopy. SEM/EDS results showed that the surface became denser, and the Zn element content decreased after polishing. Notably, the Zn content was much greater than the Cu content, which indicated that he ZPT content was much greater than the Cu2O content. In addition, the open circuit potential-pH measurement results showed that the pH value of the ZPT-SPC scratch interface generally exhibited a trend of first decreasing and then increasing, and eventually approached the original pH value. Raman results showed that the ZPT slowly diffused to the outside, which reduced the internal concentration, and the ZPT component transfer occurred inside the antifouling coating, resulting in a more uniform distribution of components. Furthermore, this process could be characterized macroscopically by antifouling agent concentration-color gray correlation model.

Electrochromic (EC) windows based on reversible metal electro-deposition/dissolution (RME) are exciting alternatives to static lighting control using blinds and shades. However, the difficulty of reversibly and uniformly electrodepositing large-area metal layers seriously hinders the development of RME-type EC windows. In this paper, we develop a novel EC system based on reversible oxide electro-deposition/dissolution (ROE) of MnO2, achieving a profound and bistable color change between rust brown and completely transparent. This ROE-MnO2 system exhibits a significantly high optical modulation amplitude (ΔT) without any deterioration within 1000 switching cycles (ΔT 550nm actually increases from 44.8 % up to 46.9 % after the cycling test), which is almost double compared to the traditional cation-insertion/extraction triggered MnO2 (RCI-MnO2) EC system. This work may inspire the exploration of novel ROE-type EC systems.

Interaction between light and magnetism in magneto-optical (MO) nanophotonic devices has been actively studied in the past few years. The recent development of MO all-dielectric resonators and metasurfaces has led to the emergence of various novel MO phenomena that were not observed in their bulk counterparts. For example, a large s-polarized transverse MO Kerr effect can be observed at magnetic resonance wavelength, which cannot exist in the bare MO films. We review recent developments in nanophotonic devices based on MO materials and focus on different modes and related MO effects in nanophotonic structures with emphasis on recently discovered new MO phenomena in magnetoplasmonics and all-dielectric nanostructures, such as dark mode, all-dielectric Mie resonance and waveguide mode. Further, we discuss the potential applications of these nanostructures for biological/chemical sensing, magnetic field sensing, and magnetic field-controlled active and nonreciprocal metasurfaces.

Layered lanthanum titanate (La2Ti2O7) perovskite is a good photocatalytic material owing to its high stability, strong redox ability, and non-toxicity. However, its inherent wide bandgap limits its application in photocatalytic hydrogen evolution. Therefore, combining La2Ti2O7 with two-dimensional (2D) narrow-bandgap semiconductors to form 2D/2D layered structures is the preferred strategy to improve its photocatalytic performance. In this study, a novel 2D/2D ZnIn2S4/La2Ti2O7 Z-scheme heterojunction was prepared through a solvothermal method. The experimental results show that when the molar ratio of La2Ti2O7 to ZnIn2S4 is 1 : 4, the hydrogen evolution rate of the composite under ultraviolet-visible light reaches 6.97 mmol g−1 h−1, which is 3.5 times higher than that of the pure ZnIn2S4. The results of the morphological characterization studies of the samples and the photoelectrochemical measurements show that channels for the rapid transfer of carriers are generated by the unique 2D/2D structure of these samples, and the separation and migration efficiency of the photogenerated carriers significantly improved due to the formation of the Z-scheme heterojunction. This study provides useful insights into the modulation of wide-bandgap semiconductors and research into solar energy conversion. [ABSTRACT FROM AUTHOR]

Electrochromic (EC) windows based on reversible metal electro-deposition/dissolution (RME) are exciting alternatives to static lighting control using blinds and shades. However, the difficulty of reversibly and uniformly electrodepositing large-area metal layers seriously hinders the development of RME-type EC windows. In this paper, we develop a novel EC system based on reversible oxide electro-deposition/dissolution (ROE) of MnO2, achieving a profound and bistable color change between rust brown and completely transparent. This ROE-MnO2 system exhibits a significantly high optical modulation amplitude (ΔT) without any deterioration within 1000 switching cycles (ΔT550nm actually increases from 44.8 % up to 46.9 % after the cycling test), which is almost double compared to the traditional cation-insertion/extraction triggered MnO2 (RCI-MnO2) EC system. This work may inspire the exploration of novel ROE-type EC systems. [ABSTRACT FROM AUTHOR]

Based on the laminar composite structure, the hardness distribution pattern and crack arrest property of Rapana venosa shell, bionic layered composite materials were prepared via hot-pressing sintering by using B4C/5083Al system and pure 5083Al as materials. The microstructure and mechanical properties were investigated by scanning electron microscope (SEM) and universal tester. The results show that on the macroscopic level, the bionic layered composite material has a multi-layered structure which is composed of hard layer of B4C/5083Al and flexible layer of 5083Al. The bionic composites exhibit “soft and hard” distribution characteristic of hardness. On the microscopic level, the hard layer of B4C/5083Al consists of B4C and 5083Al matrix, and B4C is staggered and interlinked in 5083Al matrix with combination of "soft and hard" properties. The bionic layered composites own higher compressive strength and impact toughness, and the layered overlapping structure can reset the direction of crack in the next layer, which lead the crack deflection phenomena and high impact resistance.

To study the effects of Naematelia aurantialba (NA) on the rheological and gelatinization properties of starch, the processing methods of NA were diversified. In this study, the gelatinization and rheological properties of corn starch (CS) and edible cassava starch (ECS) were investigated by adding NA with different mass fractions. Starch soft candy was prepared using NA, CS, and ECS as the main raw materials. Rheological studies showed that both CS-NA and ECS-NA exhibited elastic modulus (G′) > viscosity modulus (G″), implying elastic behavior. G′ was such that CS+1%NA > CS+5%NA > CS+3%NA > CS > CS+2%NA > CS+4%NA > ECS+4%NA > ECS+3%NA > ECS+5%NA > ECS+2%NA > ECS+1%NA > ECS. The gelatinization implied showed that after adding NA, the pasting temperature of CS-NA and ECS-NA increased by 1.33 °C and decreased by 2.46 °C, while their breakdown values decreased by 442.35 cP and 866.98 cP, respectively. Through a single-factor test and orthogonal test, the best formula of starch soft candy was as follows: 0.4 f of NA, 10 g of white granulated sugar, a mass ratio of ECS to CS of 20:1 (g:g), 0.12 g of citric acid, 1 g of red date power, and 16 mL of water. The soft candy was stable when stored for two days. This study offers a new direction for the research and development of NA starch foods. [ABSTRACT FROM AUTHOR]