Search Results (1,530)

The resource utilization of eutrophic cyanobacterial biomass provides a sustainable route for developing biochar-based catalytic materials for dye wastewater treatment. Herein, eutrophic cyanobacteria from Dianchi Lake, Kunming, were used as raw materials to prepare functional catalytic materials via pyrolysis-modification. A trimetallic photocatalyst, CuFeZnXBC₄₀₀ (XBC = cyanobacterial biochar), was fabricated for methylene blue (MB) degradation without hydrogen peroxide or other external oxidants. The samples were characterized by scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET) analysis, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), liquid chromatography–mass spectrometry (LC–MS), and three-dimensional fluorescence spectroscopy. At an initial MB concentration of 100 mg/L and pH 11, under UV irradiation, CuFeZnXBC₄₀₀ achieved nearly 99% MB removal within 60 min and retained over 90% activity after eight cycles. Transient photocurrent measurements and quenching experiments indicated that photogenerated holes (h⁺) were the dominant oxidative species, while superoxide radicals (·O₂⁻) contributed to the reaction and hydroxyl radicals (·OH) played a limited role. LC–MS analysis supported the chemical transformation of MB, and three possible degradation pathways were proposed. The development of CuFeZnXBC400 provides a new biochar-based material and a potential strategy for cyanobacterial biomass utilization and organic dye wastewater treatment. Full article

The rapid expansion of electric vehicles is generating large volumes of spent lithium iron phosphate (LFP) batteries, yet the environmental performance of closed-loop regeneration under industrial conditions remains insufficiently quantified. Here we develop a life cycle assessment of a closed-loop recycling–regeneration pathway using factory-level inventory data from an integrated plant, benchmarking 1 kg of regenerated LFP cathode-active material (CAM) at the plant gate against virgin LFP CAM (ecoinvent v3.10; ReCiPe 2016 Midpoint). Relative to virgin production, the closed-loop route reduces global warming potential (GWP100) by 7.73% (from 6.59 to 6.08 kg CO₂-eq kg⁻¹ CAM), fossil fuel potential (FFP) by 3.80%, surplus ore potential (SOP) by 97.57%, and carcinogenic human toxicity (HTPc) by 36.72%—a clear but heterogeneous advantage, large for mineral resources and modest for climate. Iron phosphate and lithium carbonate recovery dominate the burdens, with H₂O₂ being the largest single GWP100 contributor (23.7%) and the most sensitive inventory parameter, while the SOP advantage is highly robust. Grid-decarbonization scenarios widen the GWP100 reduction to 22.4% under near-zero-carbon electricity. The carbon competitiveness of closed-loop LFP regeneration is therefore governed by the balance between avoided virgin-material burdens and reagent- and energy-intensive recovery operations. Full article

Decarbonizing heavy-duty transport in the mining sector requires a deep understanding of the interplay between specific energy consumption, payload dynamics, and ambient thermal stressors. This study presents an integrated, physics-informed machine learning framework to compare the energy intensity of battery-electric (EV) and diesel internal combustion engine (ICE) tippers on a real quarry route in Poland. We develop a bidirectional, route-aware model using physical force balance and high-resolution elevation data to estimate net energy consumption and regenerative braking potential over a complete closed-loop cycle. Furthermore, an Artificial Intelligence analysis utilizing a Random Forest regressor is implemented to simulate and quantify the non-linear impacts of ambient temperature, haul road rolling resistance, and payload mass on the specific energy intensity ($E_{spec}$). Results indicate that while EV energy demand surges in sub-zero climates due to parasitic battery thermal management loads, electric powertrains exhibit a profound thermodynamic advantage during loaded downhill segments, acting as net energy generators via recuperation. The proposed multi-factor approach provides a robust predictive tool for optimizing fleet deployment, infrastructure positioning, and decarbonization pathways in transitionary mining environments. Full article

Background: The development of data processing platforms makes it possible to monitor human behavior outside the laboratory, which facilitates decision-making regarding physical activity, health, and training. Objective: Analyze the available scientific evidence on data logging in the field of sports and physical activity using development boards and microcontroller platforms. Materials and Methods: A systematic review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The selection and inclusion of studies in this review were based on the inclusion and exclusion criteria derived from the participants, interventions, outcomes (PIO) strategy. Methodological quality was assessed using the Methodological Index for Non-Randomized Studies (MINORS). Results: After all the information screening was completed, 23 documents met the eligibility criteria. The studies addressed a wide range of sports practices, including swimming, athletics, skiing, cycling, badminton, tennis, strength training, weightlifting, rehabilitation, outdoor route monitoring, and female contact-sport scenarios such as rugby, resulting in the implementation of microcontrollers in heterogeneous settings. Conclusions: For sports and health professionals, microcontroller-based systems can represent an effective way to implement objective and individualized monitoring, especially in high-performance contexts. For research, it is recommended that future studies focus on homogeneous comparisons with reference standards, larger and more diverse samples (including women), and longitudinal evaluations in real-world training and competition scenarios, so that these solutions evolve from functional prototypes into robust and transferable tools. Full article

Main memory carries data outside the processor’s trust boundary, so commodity systems-on-chip (SoCs) increasingly encrypt it; yet, in-line memory encryption engine itself becomes a differential power analysis (DPA) target whose key, if recovered, unlocks all of dynamic random-access memory (DRAM). We present PACE, a page-adaptive, cache-anchored memory encryption engine for RISC-V that makes nth-order DPA resistance practical and keeps cryptographic latency off the cache eviction critical path. PACE inserts a TileLink adapter between the last-level cache and the memory port and applies, per physical page, one of four policies (plaintext/confidentiality/confidentiality+integrity/+masking-order-d) selected from RISC-V page table bits through a memory-mapped control plane. Confidentiality uses counter mode whose per-line keystream is precomputed during cache residency; integrity is tree-free at the embedded operating point via on-chip counters and tags, with a live split counter block-MAC Bonsai Merkle tree for scale-out. DPA resistance is layered: ISAP-style fresh re-keying caps the data complexity per key at $q\approx 1$, and domain-oriented masking (DOM, d + 1 shares) protects the sole key processing block to order d. We implement PACE in Chisel on a Rocket SoC (Chipyard) and evaluate it with open-source tooling. A deterministic TileLink-level harness proves ciphertext-in-memory and detects tamper/replay/splice, and the live Tier-B engine (DRAM counters and per-line message authentication codes (MACs) plus an on-chip-rooted block-MAC tree) is validated from end to end on full Rocket and BOOM SoCs and on the FPGA; the masked Ascon-p S-box is proven order-d secure (d = 1, 2) under a glitch- and transition-aware model by three independent formal tools (COCO, PROLEAD, and SILVER, the last also deciding the full composability lattice and confirming exact glitch-robust order-2 probing security), with COCO extending the exact verdict to the highest synthesized order d = 3 (secure at probing orders 1–3); a simulated trace correlation power analysis (CPA) recovers the full key from an unprotected core and is defeated by masking, with a mutual information analysis confirming the $N\propto {\sigma }^{2(d+1)}$ trace amplification law. We further realize PACE on field-programmable gate array (FPGA) silicon: the engine plus an on-chip ring oscillator power sensor is placed, routed, timing-closed at 100 MHz, and programmed on a Xilinx XC7Z020, and we drive a fixed-vs-random Test Vector Leakage Assessment (TVLA) campaign read back entirely over a JTAG (Joint Test Action Group). A multi-core configuration and a Linux control-plane driver are likewise validated. Across synthetic access patterns and named application kernels (AES, SHA-256, matrix multiplication, pointer chasing) on both in-order Rocket and out-of-order BOOM, application-level overhead is within measurement noise of plaintext for cache resident workloads (masking, in particular, is cycle-identical to plain confidentiality), and we characterize the cost of each policy, masking order, and re-keying interval, demonstrating side-channel-hardened memory encryption on open RISC-V hardware. Full article

Deoxidized high-phosphorus (DHP) copper is widely used in marine heat-exchangers and seawater piping, where long-term structural reliability demands both high strength and a deformation-tolerant microstructure to resist damage initiation. Constrained groove pressing (CGP) is a scalable severe plastic deformation route for metallic sheets; however, the sharp trapezoidal junctions of the conventional die impose parasitic bending strains that produce sinusoidal in-plane hardness variations and anisotropic properties. This study introduces a modified CGP (MCGP) process in which the sharp crest and valley of each 45° tooth are replaced by tangent circular arcs (R₁ = 1.6 mm at the crest, R₂ = 4.8 mm at the valley), removing geometric discontinuities while exactly preserving the groove angle, pitch, and die envelope for drop-in compatibility with existing equipment. DHP copper sheets processed by conventional CGP and MCGP were systematically compared using optical microscopy, SEM, XRD, microhardness, tensile testing, and finite-element analysis. MCGP delivered exceptional mechanical performance: yield strength of 281.19 MPa, ultimate tensile strength of 451.94 MPa (96.4% above the as-received state and 23.8% above conventional CGP), mean hardness of 131.38 HV, and the finest apparent (instrument-uncalibrated) coherent diffraction-domain size of 22.75 nm. Finite-element modelling revealed a lower peak equivalent plastic strain with a more continuously distributed through-thickness deformation path, despite an unchanged nominal grooving strain (≈0.56). Notably, while the modified die redistributes deformation rather than amplifying the nominal strain, the measured through-thickness hardness inhomogeneity factor increased from 7.14% to 21.97% due to strain concentration in the mid-thickness region, indicating that full homogenisation requires further arc-radius optimisation. Nevertheless, the substantial gains in strength and microstructural refinement demonstrate that MCGP offers a promising processing route for producing DHP copper components with enhanced strength and refined microstructures, which may contribute to improved damage tolerance. However, it is acknowledged that direct tests on seawater corrosion, corrosion fatigue, and thermal cycling were not performed in this study; the implications for marine service life are inferred from the established literature on the benefits of grain refinement for corrosion and fatigue resistance. Future work incorporating marine environmental performance tests is recommended to validate these implications. Full article

The core outlet temperature is an important safety parameter for pressurized water reactors (PWRs), and its accurate determination depends on highly reliable thermocouple sensors. In this study, two typical commercial K-type thermocouple alloys (de1 and de2) were used to fabricate mineral-insulated metal-sheathed (MIMS) thermocouples. A comparative severe accelerated aging test at 500 °C for 168 h was performed to investigate electromotive force (EMF) stability under high-temperature exposure conditions. After aging, both alloy types exhibited obvious positive EMF drift, and the maximum drift magnitude appeared at the calibration temperature of 400 °C. The measured irreversible EMF drift of de2 thermocouples was lower than that of de1 thermocouples. For the same de2 alloy, thermocouples fabricated with pre-oxidized thermoelement wires presented smaller irreversible drift than those made of bright wires. Reversible EMF drift and heating–cooling calibration hysteresis were more significant for de1 specimens. Stabilization treatment at 570 °C for 2 h followed by furnace cooling effectively reduced the thermal hysteresis of both alloys during temperature cycling. This study provides straightforward experimental data and practical processing references for optimizing the manufacturing route of nuclear-grade MIMS thermocouples with improved high-temperature EMF stability. Full article

Conventional hole finishing requires separate drilling and top/bottom chamfering, and excessive insert pressure can leave scratch-type marks on the hole wall. This study develops a clip-spring-based tool that performs drilling and top/bottom chamfering in a single machining cycle, with the chamfer depth passively set by equilibrium between the hole-wall reaction and the restoring force of a replaceable clip spring. A dual-angle insert–clip-spring interface produces a non-monotonic force drop followed by a low-incremental-stiffness plateau, separating high-force burr engagement from lower-force hole passage. Four insert-geometry and spring-bottom-shape combinations were analyzed by nonlinear finite element analysis, and the two embossed-bottom cases were supported by compression tests. The dual-angle/embossed case showed a 72% Force Dip, which compression testing reproduced together with the low-force plateau, and one-step machining confirmed process feasibility. The measured hole-wall roughness decreased fourfold, from Ra 1.7 μm to 0.4 μm. These results demonstrate a passive geometric route to Force Dip generation and self-equilibrating depth setting under the tested condition. Full article

Glow-discharge plasma (GDP) poling is revisited as an electrode-free method for activating piezoelectricity in poly(vinylidene fluoride) (PVDF) films. Although this method was proposed several decades ago, its effect on the properties of PVDF films has remained poorly understood. In this work, we demonstrate that GDP enables efficient poling of oriented PVDF films without pre-deposited electrodes and investigate the relationship between plasma treatment time, structural evolution, and piezoelectric response. Commercially available 25 μm-thick oriented PVDF films (PolyK) were treated in a DC glow discharge for 15 s to 15 min and characterized using FTIR, DSC, piezoresponse force microscopy, UV–Vis–NIR spectrophotometry, quasi-static d₃₃ measurements and water contact-angle measurements. GDP poling produced a side-averaged piezoelectric coefficient d₃₃ of up to ~25 pC/N within 1–5 min, with local maxima at approximately 1, 2.5, and 5 min. This behavior was accompanied by pronounced changes in the domain structure, including an increase in the ferroelectric domain size from 86 to 552 nm, while the crystallinity and electroactive phase fraction changed only moderately. Plasma treatment also increased the wettability of the plasma-facing surface, reducing the water contact angle from about 85° to 42° within 3 min. At longer treatment times (>5 min), however, the piezoelectric response decreased and the optical transparency deteriorated because of increased haze and turbidity, most likely associated with plasma-induced chemical modification of the surface layers. These results indicate that GDP poling has an effective processing window of 1–5 min. The proposed approach provides a vacuum-compatible and electrode-free route for preparing PVDF films with increased surface wettability for flexible piezoelectric sensors, wearable electronics, and integrated polymer-based devices, because it is compatible with electrode deposition on an already activated polymer surface within a single vacuum cycle. Full article

Aligned recycled carbon fiber (rCF)/polyetherimide (PEI) tapes are a promising material for lightweight aerospace thermoplastic composite structures with reduced environmental impact, provided that their directional properties can be translated into robust components. To assess the viability of rCF/PEI for aircraft interior applications, this study tracks the development of the “Eco Bracket” across four key stages: sustainability screening, coupon characterization, microstructural interpretation, and application-level structural assessment. A project-level life-cycle assessment compared an Additive Fusion Technology (AFT) rCF/PEI bracket with cast and milled aluminum routes and yielded a short-term climate impact of 0.678 kg CO₂-eq for rCF/PEI, representing a significant reduction compared to 5.1 kg CO₂-eq for cast aluminum and 20.9 kg CO₂-eq for milled aluminum. Coupon testing characterized the anisotropic mechanical response of the rCF/PEI tape, including the elastic moduli and strengths under axial and transverse tension, in-plane shear, and axial and transverse compression. Scanning electron microscopy of a representative fracture surface showed a rough, fiber-dominated morphology with exposed fiber bundles, pull-out, and local variations in matrix coverage, supporting the interpretation that consolidation and local wet-out quality govern the transfer from coupon capability to component performance. At the application level, the manufactured rCF/PEI bracket achieved a peak load of 3517.6 N, corresponding to 93% of the strength of an industry-standard polyetherketoneketone (PEKK) reference bracket, and failed in the fastener-hole region predicted as critical by the finite element model. The combined results indicate that aligned rCF/PEI tapes can deliver mechanical properties consistent with the design requirements of aircraft interior brackets, while process robustness, fiber-path fidelity, and local consolidation quality remain the key barriers to repeatable component performance. Full article

Soil moisture is a fundamental variable controlling hydrologic partitioning, land–atmosphere exchange, and biogeochemical cycling. Although widely characterized through observations, remote sensing, and data-driven approaches, the representation of soil water fluxes and subsurface processes in predictive models remains less systematically synthesized. Here, we present a structured review of widely used predictive models, focusing on their process formulations, spatial discretization, and treatment of soil water fluxes across scales. The synthesis reveals consistent trade-offs among physical realism, scalability, data intensity, and computational efficiency. Conceptual models based on tipping-bucket approaches simplify soil water movement as threshold-driven storage processes and underrepresent transient redistribution and deep soil moisture dynamics. Storage-routing models introduce flux-based redistribution but rely on empirical parameterization that dampen transient flux dynamics. Physically based models resolve hydraulic gradients and provide the highest process fidelity but require extensive data and computational resources. Across scales, the absence or simplification of preferential flow and lateral subsurface flow constitutes the dominant structural limitation, producing systematic smoothing of soil moisture variability. The review provides a comparative basis for model selection and highlights critical directions for improving the representation of subsurface hydrologic dynamics in predictive frameworks. Full article

This study presents a screening-level conceptual, stoichiometric, and scenario assessment of a pathway linking sulfur dioxide (SO₂) capture from coal-fired flue gas to sulfuric acid production and the downstream reaction of sulfuric acid with pretreated scrap aluminum. A regenerable sodium sulfite (Wellman–Lord) capture route, followed by gas polishing and drying, catalytic SO₂ oxidation, controlled SO₃ absorption, acid conditioning, and an Al–H₂SO₄ reactor, is used as the reference configuration. The sulfur balance distinguishes sulfur in coal, ash retention, gaseous SO_x, SO₃/acid mist, absorber inlet and stack slip, captured sulfur, regenerated sulfur, and sulfate purge. Under the central assumptions, 1 t of sulfur in coal yields 0.849 t of recovered sulfur equivalent, 2.599 t of H₂SO₄, 0.477 t of aluminum feed, 2.419 t of anhydrous-equivalent Al₂(SO₄)₃, 4.240 t of commercial aluminum sulfate on a 17 wt% Al₂O₃ basis, and 42.4 kg of H₂ at 80% aluminum conversion. The upstream base-energy screen is 3.3–7.2 GJth and 0.18–0.45 MWhe per tonne of sulfur in coal. Diluting the acid to the selected 0.5–1.0 M aluminum-reaction window and subsequently producing a 17 wt% Al₂O₃ product creates a minimum water-removal load of 21.6–47.6 t and a latent-heat floor of approximately 49–108 GJth/t S. Retail prices are replaced by 2024 customs unit values, and internal-acid-production and sulfuric-acid-opportunity-cost boundaries are evaluated separately. In the central opportunity-cost case, the H₂ value must reach approximately 6.9 USD/kg merely to balance material values before CAPEX, OPEX, energy, purification, transport, and environmental-compliance costs. The Afşin–Elbistan A case is treated as a full-design-throughput illustration based on an historical 18 Mt/y coal requirement, not as a measured current operating average; coal sulfur is tested over 1.0–2.5 wt%. The aluminum step is restricted to cooled and diluted 0.5–1.0 M H₂SO₄ at 40–60 °C, and direct H₂ production from 96 to 98 wt% acid is not assumed. Plant-specific capacity factor, time-matched coal assays, flue-gas flow, oxygen-corrected stack data, reaction kinetics, gas purity, and product quality remain to be verified. The integrated sustainability screening indicates conditional circular-economy potential rather than a demonstrated sustainability advantage: sulfur recovery must be weighed against energy and water demand, sulfate purge and wastewater, diversion of recyclable aluminum from remelting, hydrogen purification, and market-scale product offtake. The pathway therefore remains a research hypothesis requiring experimental validation, process simulation, techno-economic assessment, comparative life-cycle assessment, safety analysis, and market verification. Full article

Thermoforming remains the predominant fabrication route for clear thermoplastic orthodontic appliances, yet it reduces and redistributes sheet thickness, which governs force delivered to teeth. Simultaneous thermoforming of two models may reduce fabrication time and material waste; however, its effect on final appliance thickness has not been evaluated. This in vitro study compared appliance thickness after thermoforming over a single model or two models simultaneously, using ten commercial aligner brands with different polymer composition and initial thickness. Thickness was measured with a digital caliper at anterior, canine and posterior sites, and analyzed using three-way ANOVA with Tukey post hoc tests. A significant three-way interaction (measurement point × number of models × brand; p < 0.001) was found. Significant single- versus dual-model differences emerged in some brand–region combinations; in most, dual-model appliances were thicker than single-model appliances. Four brands showed no significant difference at any site. Within the limits of this study, simultaneous fabrication of two appliances in a single thermoforming cycle produced appliances with thicknesses comparable to, and often slightly greater than, those fabricated over a single model. Simultaneous thermoforming maintained comparable appliance thickness and may improve manufacturing efficiency. Full article

Developing fiber-shaped supercapacitors (FSCs) with high capacitance, high energy density, and exceptional rate performance is crucial for reliable, stable and high-performance wearable electronics. Here, a polyaniline (PANI) @ MXene Ti₃C₂T_x/graphene (PTG) aerogel fiber was rationally fabricated via a confined hydrothermal method followed by freeze-drying treatment. The graphene sheets construct the skeleton of the aerogel fiber, which possesses a porous and interlinked structure, providing interconnected diffusion channels and a high specific surface area that promote electrolyte migration and abundant ion adsorption sites. Moreover, the covalent modification between PANI nanoparticles and Ti₃C₂T_x sheets can significantly improve interfacial coupling and provide abundant redox sites, resulting in a reduced energy barrier of electron transfer, good interfacial stability and superior H⁺ storage capability. As a consequence, the PTG aerogel fiber electrode delivers an excellent specific mass capacitance of 484.8 F g⁻¹, impressive rate properties (244.4 F g⁻¹ at 10 A g⁻¹) and exceptional cycle ability (85.2% after 5000 cycles). Additionally, the fabricated symmetrical FSC exhibits considerable electrochemical performance, including high capacitance and good energy density. This work depicts a novel route to prepare a graphene fiber-based electrode for high-performance FSCs in an intelligent wearable system. Full article

Pulse-reverse electrodeposition was investigated as a route to reduce Au consumption while maintaining coating continuity and corrosion performance in thin Ni/Au finishes. A pulse-plated Ni barrier layer with an average thickness of approximately 4.45 μm was first prepared on brass, followed by Au deposition from a potassium dicyanoaurate-based electrolyte containing a cobalt additive. Pulse frequency, duty cycle, forward current density, and reverse current density were evaluated with respect to Au thickness, surface morphology, corrosion potential, roughness, and electrochemical impedance. The processing window was selected hierarchically by requiring an Au thickness of 0.3–0.6 μm, a relatively noble corrosion potential, a compact surface with few visible defects, low roughness, and a consistent impedance response; charge-transfer resistance was not treated as the sole criterion. Within the present bath, substrate, electrode geometry, and power-supply configuration, 800 Hz, 22% duty cycle, 0.11 A·dm⁻² forward current density, and −0.004 A·dm⁻² reverse current density provided the most balanced overall response. Full article