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This study focused on the synthesis of two low-cost, highly crystallized mesoporous nanosodalites from waste materials. SOD@DWTS/SiO₂ was produced from drinking water treatment sludge (DWTS) and silicon dioxide (SiO₂), while SOD@DWTS/FA was synthesized from DWTS and fly ash (FA). This approach valorizes waste, reduces landfill use, and lowers raw material costs. By adjusting the Si/Al ratio based on the differing waste compositions, the synthesis controlled the amounts of SiO₂ and FA added. The resulting sodalites exhibited well-defined crystalline structures and spherical morphology, although their specific surface areas varied. Variations in the Si/Al ratio and substitution of commercial SiO₂ with fly ash notably influenced material properties, including crystallinity. Both sodalites showed promising adsorption of AR97 dye, with maximum capacities of 90.91 mg/g for SOD@DWTS/SiO₂ and 55.56 mg/g for SOD@DWTS/FA at pH 2 and ambient temperature, following the Langmuir model and demonstrating high efficiency. This work highlights the potential of transforming industrial by-products into valuable materials, contributing to waste management, materials science, and circular economy practices.

Treatment of fluorine-containing wastewater remains challenging. This study proposes a closed-loop method involving acidification, adsorption, alkaline elution, and regeneration for fluoride removal from wastewater using anhydrous zirconium sulfate (Zr(SO₄)₂) as a defluorination agent. Firstly, Zr(SO₄)₂ was synthesized via acidification of ZrO₂ with sulfuric acid (H₂SO₄). Secondly, under the optimal conditions of pH 4, temperature of 60°C, adsorption time of 60 min, and Zr(SO₄)₂ dosage of 1.2 g/L, the fluoride removal rate of 96.52% was achieved. The fluoride removal residue was eluted with sodium hydroxide solution, yielding a maximum fluorine elution rate of 99.78% at 1 mol/L NaOH. Subsequent re-acidification of the eluted residue with H₂SO₄ regenerated the defluorination agent. Over 10 cycles, the fluoride removal rate remained consistently above 90%. Adsorption kinetics analysis indicated that the process followed the pseudo-second-order kinetic model and the Langmuir model, with a maximum adsorption capacity of 139.86 mg/g. Material characterization revealed that fluoride adsorption on Zr(SO₄)₂ occurred mainly through chemical adsorption, forming a ZrF₄ conjugate. These results demonstrate that Zr(SO₄)₂ is a promising defluorination agent for industrial wastewater treatment, enabling effective fluoride removal with low consumption.

With the surging demand for lithium-ion batteries (LIBs), the recycling of spent LIBs has emerged as a critical endeavor for resource reuse and environmental protection. This study focuses on ion separation in the synergistic leaching solution derived from LiFePO₄ (LFP) and LiMn₂O₄ (LMO) batteries, with the objective of efficiently removing Mn, Fe, and P while recovering Li and Mn. Analysis of the Eh-pH diagram confirms the feasibility of stepwise precipitation through pH regulation. Under optimal conditions (pH 8, temperature 40°C, sodium carbonate concentration 0.75 mol/L, and reaction time 60 min), sodium carbonate as the precipitant achieves precipitation efficiencies of 99.49% for Fe, 99.89% for P, and 99.89% for Mn, with a Li loss rate as low as 0.148%. Characterizations via X-ray diffraction (XRD) and scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS) reveal that the precipitated product is spherical MnCO₃ which can be converted into polyhedral Mn₃O₄ upon calcination. The lithium-rich filtrate, after further treatment, yields columnar Li₂CO₃ that meets the specifications for crude lithium carbonate. This method offers an efficient and environmentally benign technical route for the recovery of Mn and Li from spent LIBs, thereby contributing to sustainable resource cycling and mitigating environmental impacts-aligning with the principles of cleaner production.

Non-periodic architectures observed in biological materials have been studied for their outstanding mechanical properties, such as high stiffness-to-weight ratio, energy absorption, and capacity to redistribute applied stresses. Taking inspiration from these architectures to generate engineering materials is still an open challenge. Irregular structures are challenging to model and fabricate using conventional design methods, yet they offer unique opportunities for creating functional and efficient material systems. One emerging approach is the use of tile-based computational algorithms that simulate growth processes to more effectively capture the structural irregularity of these materials. In this work, we discuss biological irregular architectures and the recent developments in computational tiling algorithms, with a particular emphasis on algorithms of virtual growth. These algorithms rely on simple tiles and a set of modifiable connection rules to generate countless complex, non-periodic structures with precise control over their geometry and topology. Recent studies have shown that material systems synthesized using tile-based designs inspired by non-periodic biological architectures can exhibit favorable properties, including enhanced impact absorbance and stress modulation. Despite this progress, integration of structure and function remains limited, highlighting the need for hybrid approaches that incorporate performance-based feedback and optimization strategies. In this context, these tools are uniquely positioned not only as generators of designs of increasing structural complexity for advanced architected materials but also as promising models for investigating fundamental questions in developmental biology.

This study explores the synergistic effects of graphite nanoparticles (0.1 wt.%) and thermal annealing (100–600°C) on electroless Ni-B coatings for AISI 4140 steel. Graphite-enabled multifunctional performance—crystallization control, friction reduction, and antibacterial activity—are unlike conventional Ni-B systems. XRD showed amorphous-to-crystalline (Ni₃B/Ni₂B) transformation, with graphite acting as a nucleation agent below 300°C before degrading at 600°C. The 300°C-annealed composite achieved optimal properties: 0.2 friction coefficient (75% lower than uncoated steel), 60% higher wear resistance, and hardness of 777 HV (+ 3.6% over as-deposited), attributed to graphite lubrication and nanocrystalline Ni₃B formation. Antibacterial tests revealed a 3.4-mm inhibition zone against E. coli, though efficacy declined at higher temperatures due to graphite oxidation. All composites maintained superhydrophilicity (contact angle ≈ 0°) without mechanical compromise. By correlating annealing temperature with microstructure, this work provides a design framework for Ni-B/graphite coatings combining low friction (μ = 0.2), high hardness (785 HV), and antibacterial functionality—addressing critical needs for wear-resistant, hygienic surfaces in biomedical and industrial applications.

This study presents a novel electrochemical comparison of WC–Co and Cr₃C₂ coatings on steel substrates, addressing a critical gap in benchmarking corrosion resistance under controlled alkaline conditions. In 3.5% NaCl, potentiodynamic polarization revealed corrosion rates of 0.065668 mm/year for uncoated steel, 0.023323 mm/year for WC–Co, and a significantly lower 0.007667 mm/year for Cr₃C₂. The enhanced performance of Cr₃C₂ is linked to its superior passivation and microstructural stability. These findings establish a unified framework for evaluating coating efficacy in aggressive environments and offer actionable guidance for material selection in corrosion-critical sectors such as offshore, mining, and chemical processing.

The Cr-Mo-Si-Ni-Al alloy system was investigated with the goal of combining recent advances in the two-phase Cr-Mo-Si system [(Cr,Mo)-A2 matrix + (Cr,Mo)₃Si-A15 precipitates], with the approach of strengthening the Cr matrix with the low misfit precipitate NiAl (B2). The role of Mo and Si in the system was investigated in alloys that were arc-melted, annealed, and characterized for microstructure, hardness, fracture toughness, and compressive strength at various temperatures (21–1000 °C). Unlike the A15 phase, the B2 phase does not reduce the fracture toughness of the Cr solid solution matrix. The yield stress of the A2–B2 system is comparable to that of the A2–A15 system, but retains its strength up to higher temperatures (tested up to 1000 °C). The addition of Ni and Al to the Cr-Mo-Si system shifts the stability regime of the σ phase in the system to lower Mo and Si contents and lower temperatures. Since Ni shows high solubility in the σ phase, reducing the Ni/Al ratio reduces the amount of the σ phase. The implementation of NiAl precipitates to the Mo- and Si-strengthened Cr matrix has a beneficial effect on the high-temperature strength and low-temperature fracture toughness of the Cr-based alloys.

This review examines advanced metal manufacturing techniques, focusing on the thermodynamic principles that govern alloying, refining, and microstructural control. Conventional methods, including electric arc furnaces (EAF), ladle furnaces (LF), vacuum arc remelting (VAR), and electroslag remelting (ESR), are evaluated alongside emerging techniques such as laser engineering net shape (LENS), selective laser melting (SLM), electron beam additive manufacturing (EBM), wire arc additive manufacturing (WAAM), and binder jetting. The analysis reveals that challenges in traditional processes—such as impurity control and volatile element management—are mirrored in the new additive technologies. To fully realize the advantages of additive manufacturing, high-temperature thermodynamic measurements must be conducted and new methodologies for quantifying thermodynamic properties will need to be developed.