Journal of Fuel Chemistry and Technology•2026•DOI: 10.3724/2097-213X.2025.JFCT.0029
Pingshuo coal ash, characterized by high silicon-aluminum content (Si+Al >85%) and low Si/Al ratio (<1.5), exhibits ash fusion temperatures (AFTs) exceeding 1550 °C, rendering it unsuitable for entrained-flow gasifiers. This study investigates the effect of calcium-sodium composite flux on ash fusibility and mineral transformation. X-ray diffraction (XRD) and FactSage thermodynamic simulations were employed to analyze mineral evolution, while molecular dynamics (MD) simulations revealed the underlying melting mechanism. Results show that adding 20% composite flux (CaO/Na2O) lowers AFTs more effectively than equivalent additions of CaO or Na2O alone, indicating a synergistic effect. At a CaO/Na2O ratio of 3:7, the flow temperatures (FT) of two Pingshuo coal ashes decreased to 1377 °C and 1279 °C, respectively. The composite flux promotes reactions between quartz and Na2O/CaO, forming low-melting-point minerals such as nepheline, albite, and gehlenite, while inhibiting mullite formation. Additionally, Na+ disrupts the silicate network, inducing Ca2+ to preferentially coordinate with [AlO4]5- tetrahedra, further breaking Si-O-Si bonds. MD simulations show that atomic diffusion, quantified by mean square displacement (MSD), is significantly enhanced below 1600 K with composite flux addition compared to single fluxes. These findings provide a mechanistic basis for optimizing flux formulations to enable efficient gasification of high-AFT coals.
Chinese Journal of Environmental Engineering•2026•DOI: 10.12030/j.cjee.202510041
This study presents a full-scale engineering practice of retrofitting an idle upflow anaerobic sludge blanket (UASB) reactor into an aerobic granular sludge (AGS) system for treating low-strength municipal wastewater. The design capacity was 20,000 m3/d (maximum 24,000 m3/d), achieving separate treatment of industrial and domestic wastewater to reduce operational costs. Systematic analysis covered hydraulic capacity enhancement, effluent quality, pollutant removal efficiencies, sludge granulation progress, and operational costs. Results showed rapid start-up: the system reached 75% of design capacity by day 10 and 90% by day 26. During a 4-month operation, average removal efficiencies for COD, NH4+-N, TN, and SS were 83.2%, 97.0%, 75.9%, and 94.4%, respectively, even under low influent BOD5/TN ratios (typically below 4). Granulation progressed quickly: by day 44, average particle size was 2.6 times that of the inoculum and over 4 times that of flocs, with granules (>200 μm) accounting for 17.3%; by day 110, these values increased to 3.2 times and 5 times, with granule proportion reaching 33.4%. Compared to the previous year (June–August), the AGS process reduced electricity consumption, chemical consumption, and sludge production by 77.3%, 25.4%, and 30.4%, respectively, while saving 65.6% of footprint. This ten-thousand-ton case provides a practical basis for AGS technology application in China.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-4097-3
The on-demand patterning of two-dimensional transition metal dichalcogenides (TMDs) with tailored edges is critical for electronic and optoelectronic applications but remains technically challenging. Here, we report a stress-guided anisotropic etching strategy for producing large-area, well-ordered MoS2 nanostructures, including nano-ribbons and nano-squares, without templates. By applying uniaxial cumulative stress followed by selective thermal etching, MoS2 monolayers are statistically etched into ribbon-like structures whose width inversely correlates with applied stress magnitude. The newly etched edges are macroscopically straight or serrated, predominantly Mo-zigzag terminated, and enhance photoluminescence by a factor of ~8.0. The edge type depends on the angle between stress direction and crystallographic orientation, corroborated by theoretical calculations. Biaxial stressing generates well-defined nano-squares, offering a scalable, versatile patterning route for engineering 2D materials with tailored functional edges, promising for electrocatalytic and optoelectronic applications.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-026-4132-y
Manganese-iron-based mixed polyanionic cathodes are promising for sodium-ion batteries (SIBs) due to high energy density and operating voltage, but suffer from Jahn-Teller distortion of Mn3+ that degrades cycling stability. Here, a structural modulation strategy via Mg2+ doping is reported. Electrochemically inert Mg2+ forms stronger chemical bonds, adjusts lattice parameters, and suppresses Jahn-Teller distortion, enhancing structural stability. Mg2+ also widens sodium-ion diffusion channels, improving diffusion kinetics. Additionally, an in-situ three-dimensional carbon nanotube (CNT) conductive network boosts electronic conductivity. The resulting NFMPP-Mg@CNTs cathode delivers a discharge capacity of 126 mAh g−1 at 0.1 C (near theoretical 129 mAh g−1), retains 80% capacity after 3000 cycles at 0.5 C, and achieves an energy density of 401 Wh kg−1, among the highest reported for mixed phosphate systems. Ex-situ XPS and first-principles calculations confirm that Mg2+ resists geometric distortion by enhancing lattice stability and widening Na+ diffusion pathways (migration barrier reduced from 0.566 to 0.398 eV). This work provides a viable route for high-energy, long-life SIB cathodes suitable for large-scale energy storage.
SCIENCE CHINA Materials•2025•DOI: 10.1007/s40843-025-3565-y
Building heating and cooling account for 60% of operational energy consumption, and conventional radiative coolers suffer from thermal accumulation and high-temperature damage under continuous solar irradiance. This work reports a dual-functional polyimide (PI)-based phase change composite aerogel that integrates latent heat storage with radiative cooling. Carbonized PI fibers (CPIF) were fabricated via electrospinning, dispersed in polyamic acid aqueous solution, and freeze-dried followed by thermal imidization to yield CPIF/PI aerogels (CPs). Vacuum impregnation with molten polyethylene glycol (PEG) produced CPIF/PI phase change materials (CPPCMs), which were surface-coated with boron nitride (BN) to obtain shape-stable BN@CPPCMs. CPIF enhances thermal conductivity and, through compatibility with the PI matrix, improves structural stability. The BN coating raises solar reflectivity, suppressing operational temperature rise. The composite prevents single-function radiative coolers from thermal accumulation and high-temperature damage, achieving high enthalpy efficiency and effective temperature regulation. The protocol addresses the bottleneck of insufficient indoor temperature regulation in energy-efficient buildings by combining solar-thermal conversion and storage with passive radiative cooling in a single shape-stable architecture.