Zinc–air batteries are promising candidates as stationary power sources because of their high specific energy density, high volumetric energy density, environmental friendliness, and low cost. The oxygen-related reactions at the air electrode are kinetically slow; thus, the air electrode integrated with an oxygen electrocatalyst is the most critical component, and inevitably determines the performance of a Zn–air battery. The aim of this paper was to document progress in researching bifunctional catalysts for Zn–air batteries. The catalysts are divided into several categories: noble metal, metal nanoparticle (single and bimetallic), multicomponent nanoparticle, metal chalcogenide, metal oxide, layered double hydroxide, and non-metal materials. Finally, the battery performance is compared and discussed.

Novel (80Li₂S − 20AlI₃)·yLiI composite solid electrolytes (y = 5, 10, 15) were prepared by mechannochemical synthesis. XRD results showed that the pattern of 80Li₂S − 20AlI₃ was similar to that of AlI₃, which means that Li₂S was dissolved in AlI₃ matrix during preparation. This structure was still maintained after LiI addition. The current measured at constant applied DC voltage indicated that (80Li₂S − 20AlI₃)·yLiI composites are intrinsically pure Li-ion conductors. The ionic conductivity at 25 °C of y = 10 was about 2.3 × 10⁻⁴ Scm⁻¹, which was about three times higher than that of y = 0. The conductivity of y = 10 increased 20 times to 2.2 × 10⁻³ Scm⁻¹ at 70 °C. These values were highest among those observed from Li₂S-based materials. It was revealed that Li-ion moves in 80Li₂S − 20AlI₃ by a hoping mechanism, while the lattice dipoles are the origin of Li-ion movement in (80Li₂S − 20AlI₃)·yLiI. The polarization measurements using Liǀ90 (80Li₂S − 20AlI₃)·10LiI ǀLi and LiǀLi₆PS₅Clǀ90 (80Li₂S − 20AlI₃)·10LiIǀLi₆PS₅ClǀLi cells proved that 90 (80Li₂S − 20AlI₃)·10LiI reacts with Li metal, but it is relatively stable at a low voltage. Sample y = 10 was also employed as a solid electrolyte in the positive electrode of a solid-state Li-S battery to study its stability in the voltage range of the positive electrode. CuS and Li_4.4Si were the electrode-active materials. The cell was cycled in CC-CV mode at 1.0 mA cm⁻² (CC) with a cut-off voltage of 1.0–2.3 V. The cell delivered a stable capacity of about 400 mAh g⁻¹_CuS after 40 cycles.

Ureolytic bacteria strains of Bacillus show its ability of calcium carbonate precipitation through metabolic activity. Different studies related to self-healing concrete material were reported associated with the generated calcium carbonate of Bacillus subtilis HU58 metabolism in recent communications. In this paper, recent findings of soil cementing with a combination of such precipitated products were presented. The experiments relied on the lab-scale studies with the use of sand-clay mixture as the controlled soil specimens. Bacillus bacteria and nutrients were mixed to introduce in the sand matrix and then curing in high moisture condition. The composition and morphology of soil specimens were characterized after solidifying by FTIR, XRD, and SEM. Water percolation and mechanical stability for the physicomechanical properties were also tested with the unconventional method. Discussing the relevant results can help to figure out the next experiments in the field of geotechnical engineering. From the perspective of this study, the sustainability factor should be considered to apply this promising technique for soil stabilization and improvement and/or for the formulation of bio-brick as an alternative to sintered clay-based brick. From the perspective of this study, this technique for soil stabilization and improvement and/or for the formulation of bio-brick can be considered a promising sustainable alternative to sintered clay-based brick.

INFLUENCE OF DYNAMIC PROCESSES ON MORPHOLOGICAL CHANGE IN THE COASTAL AREA OF MEKONG RIVER MOUTH

In this study, we investigate using acrylic and acrylic-styrene emulsions as curing solution to enhance water resistance and prevent cracking in cement concrete surfaces. Our main objective is to investigate the possibilities of utilizing washing waste generated during the Rhomn & Haas factory - Dow Chemical Vietnam production process. This waste is currently being treated as solid even though it contains anywhere from 10-45% solid content. Through laboratory-scale experiments and analysis, we aim to assess the feasibility of employing this waste material as a cost-effective, technically sound, and environmentally sustainable solution for curing compound of concrete. The findings of this research have the potential to contribute to the advancement of eco-friendly waste management techniques while improving the durability and effectiveness of cement structures.