Terbium-161 (Tb-161) emits gamma rays and beta radiation, enabling both therapeutic and imaging applications. However, the multiple gamma emissions of 161Tb can affect image quality by increasing the scattering rate during SPECT imaging. To improve image quality, appropriate scatter correction methods, such as Dual-Energy Window (DEW) and Triple-Energy Window (TEW) need to be optimized. Although these methods are used in clinical practice, studies investigating the efficacy of spectral analysis approaches for next-generation radionuclides with multiple gamma emissions, such as 161Tb, are limited. This study aims to evaluate the effects of DEW and TEW scatter correction methods on image quality and quantitative accuracy in 161Tb SPECT imaging compared to uncorrected images. Three distinct reference geometries were utilized to determine the gamma camera calibration factor (CF) and to evaluate the image quality parameters. Five image protocols were used, each with different combinations of main photopeak and scatter energy windows. Image quality parameters (CF, contrast-to-noise ratio (CNR), signal-to-noise ratio (SNR), spatial resolution) and activity bias (%) were compared using LifeX software in both uncorrected and corrected SPECT images. The CF calculated in images acquired with an energy window of 48.9keV was found to be higher than that calculated in an energy window of 74.6keV. The best CNR was calculated for images acquired in air with a photopeak of 48.9keV±10% and a scatter window of 6%. In scattered media, it was observed in images obtained with a photopeak of 74.6keV±10% and a scatter window of 6%. When scatter correction was applied, the images' SNR values decreased slightly, ranging from 1.188 to 1.724 across all media. Scatter correction techniques reduced the FWHM values for all protocols except the air medium, thereby improving spatial resolution. Activity bias results showed an overestimation in uncorrected protocols including the 48.9keV peak. Conversely, utilizing the 74.6keV peak with TEW correction improved quantitative accuracy to a 3.7%-4.2% absolute bias. Our results show that both DEW and TEW correction approaches improve spatial resolution and increase CNR by reducing scattering contributions and background noise. However, as expected with the subtraction of scattered effects, these enhancements are accompanied by a slight decrease in SNR. The TEW method performed better than the DEW method in terms of quantitative accuracy under scattering conditions. In SPECT imaging using therapeutic amounts of Tb-161, high image quality can be achieved with an energy window of 74.6keV±10%.

Accurate range verification is crucial in hadrontherapy to fully exploit the ballistic advantages of charged particles and prevent damage to healthy tissues. Among the proposed approaches, prompt gamma imaging (PGI) has emerged as an effective technique for real-time monitoring, but its performance is limited by the intense neutron background generated during irradiation, especially withcarbon-ions. This work presents a Monte Carlo study performed with the FLUKA code to investigate prompt gamma and neutron emission in proton and carbon-ion therapy. A prototype detection system based on a knife-edge collimator coupled to a pixelated LYSO scintillator was simulated to evaluate its capability for range verification. The aim is to quantify how neutron fields and neutron induced signals bias or degrade range related quantities, and how these effects differ between proton and carbon-ionbeams. The analysis includes the characterization of prompt gamma energy spectra and spatial profiles, the assessment of neutron fields within a treatment room, and the decomposition of the detector signal into primary gammas, secondary gammas, andneutrons. Results show that prompt gamma profiles correlate well with the Bragg peak position, particularly within the 3-7MeV energy window, while carbon ions exhibit higher prompt gamma yields but also significantly stronger neutron backgrounds compared to protons. Detector simulations highlight the impact of neutron capture on lutetium, producing distinct peaks that must be accounted for in the detector signal analysis. The fall-off retrieval precision (FRP) analysis indicates that the distal fall-off of prompt gamma profiles can be used to estimate the Bragg peak position, while secondary radiation components introduce additional fluctuations that affect the achievable precision, particularly for carbon-ionbeams. The study provides a detailed characterization of prompt gamma and neutron contributions in proton and carbon-ion therapy and highlights the main physical factors affecting PGI-based range monitoring, particularly in the presence of neutron-induced backgrounds. These results provide useful insights for the design and optimization of prompt gamma detection systems in clinicalapplications.

We present a computational framework for the systematic exploration of high-dimensional potential energy surfaces associated with host-guest interactions in porous materials. As case studies, the adsorption of benzyl alcohol, benzene, benzaldehyde, CO, CO2, H2S, and methanol in the metal-organic frameworks MFM-300(Sc) and MFM-300(In) was investigated. A stochastic sampling strategy generated thousands of candidate configurations, which were first screened at the semiempirical PM7 level and subsequently refined using dispersion-corrected density functional theory. To identify representative low-energy structures while preserving configurational diversity, a data-driven selection procedure based on outlier detection and unsupervised clustering of energetic and geometric descriptors was implemented. The exploration of approximately 39 000 configurations reveals that the adsorption landscapes are characterized by multiple low-lying minima within narrow energy windows, particularly for weakly interacting guest molecules. This behavior reflects the complex and highly corrugated potential energy surfaces associated with confinement in MOF pores and highlights the limitations of approaches based on chemically intuitive initial guesses or single optimized structures. The multilevel protocol provides a statistically robust and computationally efficient strategy for identifying adsorption sites and representative configurations in porous materials, and offers a transferable framework for exploring configurational landscapes in host-guest systems, heterogeneous interfaces, and other complex condensed-phase environments.

Objective. The 3D CZT SPECT-CT offers betterγray detection, particularly improved energy resolution, which could be useful for more accurately accounting for scattered radiation. These new cameras also benefit from advanced reconstruction methods. Notably, the BSREM algorithm controls noise during the iterative process. This study aims to investigate the influence of using a narrow energy window for scatter correction on image quality and quantification performance. It will also examine the regularisation methods (and their parameters) implemented by the manufacturer.Approach. Acquisitions were performed on two99mTc-filled phantoms (a thorax-mimicking phantom including a myocardium insert and a cylindrical tank). Scatter was taken into account using the Jaszczak subtraction method (DEW) and a narrow photopeak window (SEW). The images were reconstructed using the Median Root Prior and Relative Difference Prior regularisation methods. The following were evaluated: sensitivity, sharpness index (a spatial resolution indicator), contrast-to-noise ratio, signal-to-noise ratio, and concentration recovery.Main results.Sensitivity was independent of the regularisation method and was measured at (942.4±2.1) and (1074.4±12.8) counts.(MBq.s)-1, respectively, for DEW and SEW. The sharpness index ranged from (0.138±0.014) to (0.033±0.003) mm-1, the contrast-to-noise ratio ranged from (4.0±0.2) to (2.1±0.1), and the signal-to-noise ratio ranged from (11.2±0.4) to (4.1±0.1). Concentration recovery decreased with theβparameter for both MRP and RDP, as well as for both scatter corrections.Significance. Using a narrower spectrometric window makes the system more sensitive, providing equivalent image and quantification quality to that achieved using the Jaszczak subtraction method. When the BSREM reconstruction method is used, the quality of the images and the quantification in myocardial SPECT-CT are highly dependent on the regularisation methods and their parameters.

This study introduces an innovative “energy–structure–performance”framework to quantify mixing intensity in stirred crude oil desalting,moving beyond traditional metrics such as stirring speed and duration.By analyzing droplet size distribution and estimating input energyvia a Reynolds number–Power number approach, we identifieda critical input-energy window centered around 50 J. Within this range,desalting efficiency exhibits a characteristic rise–fall trendthat closely mirrors the evolution of the Sauter mean diameter (D32) along the energy axis, emphasizing the pivotal role ofdroplet structure in translating energy input into performance. Mechanistically,operating within this optimal energy window promotes droplet coalescencewhile minimizing shear-induced overemulsification. These results providea physically grounded methodology for refining engineering operations,allowing precise control of mixing valves and optimization of energyinput to achieve enhanced salt removal and improved phase separationefficiency.

Low-temperature plasma processing is a promising technique for tailoring transition metal dichalcogenides (TMDs). For chalcogen substitution processing, a key challenge is to identify the ion energy window that enables selective chalcogen removal while preserving the metal lattice. Using ab initio molecular dynamics (AIMD), we demonstrate that oxygen and fluorine functionalization widen the processing window by significantly lowering the sulfur sputtering energy threshold (Esputt,S) of MoS2 from ∼30 to ∼10 eV via formation of sputtering products such as SO2 and SFn. Additionally, we show that experimentally relevant cryogenic temperatures strongly affect Esputt,S(T) . The dependence is confirmed via AIMD and also predicted by a mechanistic parameter-free theory, suggesting that Esputt (T) generalizes to other TMDs, functionalizations, and surface impact conditions. Our results highlight oxygen/fluorine functionalization, ionic impact angle, and material temperature to be key control parameters for selective, damage-controlled chalcogen removal in TMD processing.

Abstract We report a broadband spectroscopic-ellipsometry study of high-quality (Cu, C)Ba2Ca3Cu4Oy thin films (hereafter abbreviated as (Cu, C)-1234), aimed at tracking the temperature dependence of the electronic structure from 0.5 to 4.2 eV. From the extracted complex dielectric function, we obtain the real optical conductivity σ1 (ω) and quantify spectral-weight redistribution in four energy windows that separate the low-energy intraband response in contrast to the mid- and high-energy Cu-O interband/charge-transfer excitations. Upon cooling, the spectra display a redistribution of optical spectral weight that spans more than 1 eV, far larger than the superconducting gap, indicating correlation effects beyond a weak-coupling picture. The low-energy intraband spectral weight is suppressed near a pairing-onset temperature Tconset and partially recovers below the zero-resistance temperature Tc0, while weight in Zhang-Rice-singlet and LHB-UHB charge-transfer channels increases, with the largest high-energy enhancement appearing at or just below Tc0. These observations may indicate a two-stage evolution of the electronic structure, in which precursor pairing or phase fluctuations first reduce the single-particle coherence, followed by further spectral reorganization at lower temperatures. However, considering the relatively broad resistive transition of the film, the observed spectral-weight changes may also be influenced by percolative superconductivity or by a distribution of local transition temperature in the film. This eV-scale spectral-weight redistribution may reflect related electronic or lattice effects discussed in previous studies of cuprates. Our results demonstrate that low- and high-energy electronic degrees of freedom are cooperatively involved in the superconducting transition of multilayer cuprates, thereby motivating layer-resolved spectroscopies and theoretical efforts to clarify the microscopic coupling mechanisms.

Abstract Topological semimetals (TSMs) featuring symmetry-protected band degeneracies have attracted considerable attention due to their exotic quantum properties and potential applications. While nodal line (NL) and nodal surface (NS) semimetals have been extensively studied, the realization of a material where both NL and NS coexist and are intertwined, particularly with an ideal electronic band structure, remains a significant challenge. Here, we predict via first-principles calculations and symmetry analysis a metastable boron allotrope, Porous-B$_{18}$ (space group $P6_3/m$, No. 176), as a pristine TSM hosting a NS and two straight NLs near the Fermi level. The structure, a honeycomb-like porous 3D framework, exhibits excellent dynamical, thermal (stable up to 1000 K), and mechanical stability. Its electronic band structure is remarkably clean: only the highest valence band (HVB) and the lowest conduction band (LCB) cross linearly within a large energy window of 1.84 eV, free from trivial-band interference. The nodal surface lies on the $k_z = \pm \pi$ planes, protected by combined time-reversal symmetry ($T$) and twofold screw-rotational symmetry ($S_{2z}$), yielding a full-plane Kramers-like degeneracy. The two nodal lines along $K$-$H$ and $K'$-$H'$ are protected by inversion and time-reversal symmetries, carry a quantized Berry phase of $\pm \pi$, and connect orthogonally to the nodal surface, forming an intertwined nodal network. Drumhead surface states on the $(1\bar{1}0)$ surface further confirm the nontrivial topology. Porous-B$_{18}$ thus provides an ideal platform for investigating the interplay between nodal-line and nodal-surface fermions and exploring novel quantum transport phenomena.

The recent emergence of altermagnetism has enriched the classification of magnetic states. The symmetry constrained even-parity and odd-parity altermagnets are mainly limited to collinear and noncollinear spins in two- and three-dimensional materials. In this work, guided by the symmetry classification, we propose a general strategy for designing unconventional p-wave altermagnets in one-dimensional (1D) collinear antiferromagnets with the switchable spin-splitting under circularly polarized light, also extendable to the odd-parity altermagnets in two-dimensional (2D) collinear antiferromagnets. First-principles calculations on experimentally synthesized 1D and 2D triangulene crystals further validate our design principles, realizing the extrinsic p-wave and f-wave altermagnets. By coupling 2D altermagnetic triangulene crystals to s-wave superconductors, the high-Chern-number topological superconductivity can be achieved within spin-splitting energy windows. Our work introduces a new mechanism to engineer light-induced 1D and 2D odd-parity altermagnets and provides a molecular platform to explore the metal-free altermagnetism in π-conjugated covalent organic frameworks.

The digital cadmium-zinc-telluride (CZT)-based SPECT system offers good energy resolution. However, the impacts of dual-energy window scatter correction on image quality under narrower primary energy windows remain to be determined. This study aimed to assess the impacts of SC (with scatter correction) and NOSC (without scatter correction) on image quality under different primary energy windows. We used a standard NEMA/IEC 2007 phantom containing six hollow spheres of various sizes to simulate the human body at four target-to-background ratios (T/B ratio, the ratio of the average radioactive activity concentration in the target region to that in the background region, 32:1, 16:1, 8:1, and 4:1, respectively), by filling with 99mTcO4-. For clinical validation, we recruited 20 patients and analyzed their whole-body bone scan images. Phantom and patient images were acquired with the Discovery NM/CT 670 CZT with list mode. Image quality of phantom was measured by calculating indicators from the NEMA NU 2-2018 standard, including percent background variability and percent contrast. Image quality of patients was measured by calculating coefficient of variation (COV), contrast-to-noise ratio (CNR), and signal-to-noise ratio (SNR). Visual quality was evaluated by two experts. Higher percent background variability and COV values were present when SC was applied regardless of which energy window, acquisition time, or T/B ratio used, and statistically significant differences were observed between all SC and NOSC groups for both phantoms and patients. For phantoms, percent contrast values of most SC groups were higher than those of NOSC groups. For patients, CNRs and SNRs of SC groups were higher than those of NOSC groups (all P < 0.05). Visually, SC had higher visual scores than NOSC for both phantoms and patients. SC significantly improves image contrast while minimizing concomitant image noise to a great extent and provides good visual image quality across different primary energy windows overall.

Abstract We study smooth linear spectral statistics of twisted Laplacians on random n -covers of a fixed compact hyperbolic surface X . We consider two aspects of such statistics. The first is the fluctuations of such statistics in a small energy window around a fixed energy level when averaged over the space of all degree n covers of X . The second is the centered energy variance of a typical surface, a quantity similar to the normal energy variance. In the first case, we show a central limit theorem. Specifically, we show that the distribution of such fluctuations tends to a Gaussian with variance given by the corresponding quantity for the Gaussian Orthogonal/Unitary Ensemble (GOE/GUE). In the second case, we show that the centered energy variance of a typical random n -cover is that of the GOE/GUE. In both cases, we consider a double limit where first we let n —the covering degree—go to ∞ then let L → ∞ where 1/ L is the window length. A fundamental component of our proofs are the results we prove in [11] which concern the random cover model for random surfaces.

Recent developments in vehicle-to-grid (V2G) technology have positioned electric vehicles (EVs) as essential components for increasing the use of renewable energy and managing peak demand. However, while V2G systems utilize blockchain technology for secure energy transactions, they encounter notable inefficiencies due to the high volume of transactions when the number of energy participants increases. The communication overhead associated with processing energy supply and demand is significant. In addition, current energy distribution systems do not fully exploit the potential of EVs. They cannot schedule multiple discharge cycles for a single vehicle over specific periods. Furthermore, existing systems do not provide mechanisms that allow EVs to make smart autonomous decisions about their charging and discharging operations. Instead, they are usually dependent on fixed schedules or manual inputs, which further exacerbates the inefficiency of energy management and market integration. This paper proposes a novel edge-driven two-tier blockchain-based V2G method to optimize the energy management of distributed electric vehicles. The architecture incorporates local dual networks within an electric vehicle blockchain (EVBC) and an energy market blockchain (EMBC), coordinated by a high-level blockchain that manages unfulfilled requests. A dynamic segment-based energy allocation algorithm (DSBEA) is introduced, where the control system allocates energy requests by matching EV offers while continuously updating each EV's remaining energy and available time window after each assignment. The evaluation showed a significant reduction in total time cost compared to baseline methods, with reductions ranging from 42% to 80% in various energy trading scenarios. In addition, the proposed method achieved a 68.6% increase in energy fulfillment compared to the best existing approaches.

ABSTRACT This work reports a density functional theory (DFT) study of the adsorption and desorption of hydrogen on the van der Waals (vdW) heterostructure (1QL)/Gr(ML). Three configurations are compared: pristine, single, and double Se‐vacancies. The calculations are performed along with the investigation of charge density distribution within a specific energy window. Our results indicate that hydrogen atoms chemisorb through the bond formation with the surface atoms. The adsorption energy, charge transfer, and electronic properties are analyzed to understand the interaction strength. The adsorption energies for one H atom on pristine and vdW heterostructures are –2.12 and –2.67 eV, respectively, while the system shows moderate adsorption (–1.03 eV) with moderate desorption time, indicating reversible hydrogen behavior. For multiple hydrogen adsorption (2H, 4H, 6H) on system, adsorption energy becomes progressively more negative, suggesting that the Se vacancy enhance hydrogen binding with increasing coverage. Desorption‐time calculations indicate excellent hydrogen‐sensing and recovery potential at elevated temperatures. Linear Dirac dispersion of graphene remains preserved near the Fermi level, and defected surfaces shows improved stability and reversible behavior highlighting their potential for hydrogen‐storage and catalytic applications.

Abstract Atomic layer etching (ALE) of AlN is an important process for enabling high-precision patterning in advanced photonic and electronic devices. In this study, ALE of sputter-deposited AlN thin films was carried out using an ALE approach consisting of Cl 2 -based surface modification followed by an Ar ion bombardment step. The developed process exhibited highly self-limiting behavior with etch-per-cycle approaching the thickness of a single AlN monolayer, a process synergy of 82%, and a post-etch RMS surface roughness as low as 0.6 nm. To define the ALE ion energy window, ion energy distribution functions were measured and calibrated by taking into account the voltage drop across the dielectric layer on the wafer surface. This calibration revealed a significant reduction in effective energy of ions reaching the wafer surface and a corresponding shift in the ALE ion energy window when expressed in terms of the peak-to-peak voltage. The ALE ion energy window for AlN was experimentally determined to be between 142–196 eV, which is in good agreement with molecular dynamics simulations predicting the lower threshold of the window to be 150 eV. These findings underscore the importance of considering dielectric stack thickness in ALE and conventional plasma processing.

ABSTRACT Quantum spin Hall edge transport in 2D transition‐metal dichalcogenides depends on whether their 1D edge channels are preserved under realistic substrates and device boundaries. Here we implement spin‐orbit coupling in DFTB and GFN‐xTB within the Amsterdam Modeling Suite, and apply it to heterostructures. Edge‐projected spectra reveal robust edge states in ribbons; these states remain robust against a laterally infinite H substrate, which only shifts the Dirac point via long‐wavelength corrugation without introducing additional in‐gap states. By contrast, terminated H edges generate trivial dispersion branches in the same energy window that hybridize only weakly with the topological edge modes. In the bulk, Fermi‐level states are ‐derived; at the small twist angle, lattice‐relaxation‐induced strain drives miniband reconstruction, whereas at the large twist angle, the layers become electronically decoupled. These findings suggest the conditions – controlled twist angle and avoidance of terminated H edges – for achieving quantized conductance and unambiguous spectroscopic detection of helical edges.

Metal nanoparticles produced by wire electrical explosion inherently contain structural defects that generate extra stored energy, making them promising additives for energetic materials. In this study, ReaxFF molecular dynamics simulations were performed to investigate the melting behavior and energy release mechanisms of defect‐containing copper nanoparticles. Copper nanoparticles with diameters of 2–4 nm and vacancy defect concentrations of 2%–10% were analyzed using radial distribution functions, potential energy, face‐centered cubic (FCC) fraction, and extra stored energy. The results show that the transition temperature decreases with decreasing particle size, consistent with the Gibbs–Thomson effect, and that melting initiates at low‐coordination surface atoms before propagating into the FCC core. Notably, the extra stored energy exhibits sharp peaks at the melting transition, reaching approximately 580 kcal/mol at 10% defect concentration. These findings demonstrate that defect‐induced energy is rapidly released during melting, highlighting the potential of defect‐engineered copper nanoparticles as additives for ignition and combustion enhancement in energetic materials.

Topological catalysts are special class of high-activity catalysts that have topological surface state with high-mobility electrons to promote electron transfer. Among topological materials, high-fold degenerate topological semimetals (TSMs) with chiral structures are particularly effective in hydrogen evolution reaction (HER) catalysis due to the larger energy window of nontrivial surface states and longer Fermi arcs than other classes. In this work, based on high-throughput calculations and the database of high-fold degenerate TSMs with chiral structures that we have established, we predict 16 high-activity topological catalysts with Gibbs free energy ∣ΔG∣ smaller than that of Pt. Among them, PtGa and PtPbTe with space group P213 and Pd3Pb2S2 with space group I213 exhibit outstanding catalytic behavior. Furthermore, by comparing the adsorption energy on the surfaces with and without topological surface state in the same compound straightly, the substantive fact that the extremely long topological surface state provides virtual improvement of HER catalytic performance is verified. Thus, this work not only discovers a lot of HER topological catalysts, but also provides and corroborates an innovative strategy to design high-activity catalysts, i.e., constructing monometallic catalysts into TSMs.

Objective.This work aims to evaluate the performance characteristics of S-positron emission tomography (PET), a compact, phoswich detector small animal PET prototype developed at Shenzhen Bay Laboratory (SZBL), in accordance with the National Electrical Manufacturers Association (NEMA) NU4-2008 protocol.Approach.The S-PET system comprises twenty flat-panel detectors arranged in two rings, with an inner diameter of 80 mm and an axial field of view (FOV) of 104.5 mm. Each detector adopts a phoswich depth of interaction design, consisting of two layers of scintillator crystal arrays, an oblique edge-cut glass lightguide, and two multi-pixel photon counter arrays. The front layer (annihilation photon entrance) is a 30 × 60 pixelated cerium-doped lutetium yttrium orthosilicate (LYSO) array (0.79 × 0.79 × 5 mm3per crystal), while the back layer (towards multi-pixel photon counters) is a 20 × 40 pixelated bismuth germanate (BGO) array (1.22 × 1.22 × 7.5 mm3per crystal). This phoswich design enables identification of most cross-layer crystal scatter (CLCS) events. Performance evaluation was conducted following NEMA NU4-2008 standards, including sensitivity, energy resolution, spatial resolution, noise equivalent count rate (NECR), scatter fraction (SF), image uniformity, spillover ratio, and recovery coefficient (RC).Main results.Within the 350-650 keV energy window, the peak absolute sensitivity at the FOV center was 14.9% (with CLCS events) and 11.9% (without CLCS events). The average system energy resolution was 10.7% ± 2.0% for LYSO and 28.1% ± 4.5% for BGO, derived from averaging individual crystal spectra. For three-dimensional ordered-subsets expectation maximization reconstructed images with spatially variant point spread function modeling, the spatial resolution of a point source in air ranged from 0.65 mm to 1.08 mm, with an average of 0.78 ± 0.12 mm across all measured locations. For the mouse-sized phantom, the peak NECR was 237.4 kcps at 11.9 MBq, with a SF of 13.0%; for the rat-sized phantom, these values were 110.3 kcps at 11.9 MBq and 23.3%, respectively. For the NEMA image quality phantom, the uniformity was 6.3%, spillover ratios in water-filled and air-filled cold region chambers were 11.1% and 7.9%, respectively, and RCs ranged from 0.36 to 0.89.Significance.The comprehensive performance results demonstrate that the S-PET prototype developed at SZBL possesses high spatial resolution and high sensitivity. These characteristics meet the requirements of preclinical research, particularly forin vivoimaging of small animals such as mice and rats.

Heat-, water-, and chemical-free delamination of lithium iron phosphate (LFP) cathodes from Al foil was achieved using electrical pulsed discharge. Three feedstocks were tested: production scrap lacking electrolytes, freshness-equivalent spent cells (SOH100), and degraded cells (SOH83). Energy inputs of 0.56–0.59 J mg–1 were supplied. Scrap without LiPF₆ required 0.59 J mg–1 to exceed 98% delamination, indicating that interfacial failure depended on Joule heating and thermal stress. Residual LiPF₆ generated HF in situ, weakening the PVDF bond and delivering ≥ 97% delamination across the energy window in SOH100. The spot-like interfacial degradation in SOH83 disrupted current pathways, requiring higher energy and reducing delamination ratio. Thermal modelling showed concentrating current within Al foil raised the interface to 536–554 K, sufficient to melt PVDF and induce through-thickness stress while avoiding bulk heating. The recovered powders from all runs were free of Al-foil contamination (< 0.1 wt.%). X-ray diffraction before and after discharge showed identical LFP peak positions and intensities, confirming no chemical conversion or crystallinity loss occurred, enabling direct recycling. A new electrode with 10 wt.% recovered LFP delivered 148 mAh g–1 at 0.1 C without increased impedance. Pulsed discharge provides high-yield, contamination-free pretreatment for phosphate-cathode direct recycling.

Controllable X-ray density calibration: A safe replacement for Cs-137 radioactive source.