Direct regeneration of electrode materials is the optimal choice for sodium-ion batteries (SIBs) recycling due to their high economic efficiency and environmental friendliness. The residual contaminants of spent hard carbon (HC) anodes are predominantly water-soluble sodium salts, which might enable efficient direct regeneration of HC, which is a key issue for addressing the economic challenges of recycling. This study characterizes the failure mechanisms of large format prismatic SIBs and develops a straightforward strategy for the direct regeneration of hard carbon. The exsolution of the transition metal Fe from NaNi1/3Fe1/3Mn1/3O2 induced the formation of thick interfacial layers on both the anode and cathode, impeding sodium ion transport. Pyrolysis and acid-washing techniques facilitated the decomposition of impurities and the removal of Fe elements, successfully restoring the sodium storage performance of HC, with an initial reversible specific capacity of 300.3 mAh g-1. Furthermore, a more uniform and thinner interfacial film enriched with NaF was constructed using 0.5 % HMDS and 0.5 % NaDFOB additives in the full cell with a capacity retention of 74.6 % after 200 cycles. This study highlights the low cost and convenience of direct regeneration of hard carbon, which is conducive to creating a circular economy for the SIBs industry in the future.
Two singularity-removing Chebyshev collocation methods are proposed for discretizing nonlinear fractional differential equation with singular solution at the initial and terminal points. By reformulating the problem into the Volterra integral equation of the second kind, we obtain the fractional series solution around the origin via successive approximation, which depicts the initial singularity of the unknown solution accurately. By removing the singularity at the origin, we design two Chebyshev collocation methods to solve the equivalent Volterra integral equation and Hadamard finite-part integral equation on a regular interval. The convergence of the scheme for the equivalent Volterra integral form is proved. For blow-up problem, we perform the Pad & eacute; technique for the obtained series solution to detect the blow-up time. We also explore the blow-up behavior of the solution for three typical types of nonlinear term. By removing the dominant term of the blow-up behavior from the equation, the accuracy of the collocation methods is improved significantly. Finally, numerical examples demonstrate the high efficiency and exponential convergence of the singularity-removing Chebyshev collocation methods.
The study surveyed 451 undergraduate students from a Chinese university and found that teacher autonomy support affects student engagement through the chain mediating effect of student’s motivational belief and SRL. This study not only explores the direct impact of teacher support on student engagement but also investigates the mediating mechanisms of this influence. This paper helps to fully reveal the relationship between teacher support and student engagement, providing theoretical support for colleges and universities to formulate effective educational policies to enhance the learning engagement of college students. The study cannot only deepen our understanding of college students' learning engagement behaviors, but also provide practical guidance for constructing a learning environment that promotes college students' learning engagement.
Problematic smartphone use (PSU) has become a significant global concern with major implications for mental health and well-being. Using a multi-site longitudinal design (N = 282, follow-up ranging from 5 months to 5 years), this study examined the predictive role of the default mode network (DMN) in PSU development and its underlying psychological and transcriptomic mechanisms. We found that baseline gray-matter volume (GMV) in the anterior DMN-particularly the ventromedial prefrontal cortex (vmPFC)-and regional homogeneity (ReHo) in the posterior DMN-especially the posterior cingulate cortex (PCC)-significantly predicted the severity of subsequent PSU. Additionally, these neural features exhibited distinct psychological mediation pathways, demonstrating a double dissociation effect: the structural features of the anterior DMN influenced PSU through fear of missing out (FoMO) at follow-up, whereas posterior-DMN functional features operated via follow-up negative affect (NA). Transcriptomic analysis revealed that genes associated with PSU-related brain functional patterns (n = 150) are enriched in synaptic transmission and glutamatergic pathways, showing an expression imbalance between excitatory and inhibitory neurons, with expression peaking from infancy to adolescence. GAMBA analysis identified three gene modules linked to DMN metabolic activity. Together, these findings illuminate the anterior-posterior dissociation within the DMN in PSU development and highlight specific psychological-neurobiological pathways and transcriptomic signatures that provide a molecular framework for understanding the biological processes underlying PSU.
We introduce a mock galaxy catalog built for the China Space Survey Telescope (CSST) extragalactic surveys using the primary runs of the Jiutian N-body simulation suites. The catalogs are built by coupling the galaxy evolution and assembly (gaea) semi-analytical model of galaxy formation with merger trees extracted from the simulations using the hierarchical bound-tracing (hbt+) algorithm. The spectral energy distributions (SEDs) and broadband magnitudes are computed using the neural-network-based stellar population synthesizer StarDuster, which is trained on radiative transfer simulations to account for detailed galaxy geometry in modeling dust obscuration. Galaxy light-cones up to z = 5 are subsequently generated with the Blic light-cone builder, which interpolates the properties of galaxies over time using an optimized interpolation scheme. The resulting catalogs exhibit good convergence in many statistical properties of the galaxy population produced from two different resolution simulations. The catalogs reproduce a number of observed galaxy properties across a range of galaxy mass and redshift, including the stellar mass functions, the luminosity function, gas mass fraction, galaxy size-mass relation, and galaxy clustering. We also present the photometric and redshift distributions of galaxies expected to be observed in the CSST surveys.
