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Search Results (794)

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20 pages, 10531 KB  
Article
Tungsten-Promoted Nickel–Molybdenum Catalysts Prepared by Electroless Deposition for Borohydride Hydrolysis
by Gitana Valeckytė, Zita Sukackienė, Virginija Kepenienė, Raminta Stagniūnaitė, Lukas Šimkus, Loreta Tamašauskaitė-Tamašiūnaitė and Eugenijus Norkus
Coatings 2026, 16(7), 754; https://doi.org/10.3390/coatings16070754 (registering DOI) - 25 Jun 2026
Abstract
The production of high-purity hydrogen from chemical hydrogen storage materials such as sodium borohydride (NaBH4) has been identified as a particularly promising candidate due to its high hydrogen storage capacity and environmentally benign hydrolysis products. The incorporation of tungsten (W), thereby [...] Read more.
The production of high-purity hydrogen from chemical hydrogen storage materials such as sodium borohydride (NaBH4) has been identified as a particularly promising candidate due to its high hydrogen storage capacity and environmentally benign hydrolysis products. The incorporation of tungsten (W), thereby developing W-promoted NiMo catalytic systems, results in the enhance activity toward NaBH4 hydrolysis, thereby developing ternary NiMoW catalytic systems. The synthesis of NiMoW-coated copper catalysts (NiMoW/Cu) containing 3–11 wt.% of W was accomplished using a cost-effective and efficient electroless deposition method from citrate-based plating baths containing Ni2+, Mo6+, and W6+ ions. Morpholine borane was utilized as the reducing agent in this process. The catalytic activity of the prepared coatings toward alkaline NaBH4 hydrolysis increased as the tungsten content decreased within the investigated range of 3–11 wt.%. The highest hydrogen generation rate, reaching 9.87 L min−1 gcat−1, was achieved using the NiMoW/Cu catalyst containing 3 wt.% of W at 343 K. The corresponding apparent activation energy was calculated to be 52 kJ mol−1. In addition, the catalyst demonstrated notable 89.1% stability, maintaining a high degree of catalytic activity after undergoing five successive hydrolysis cycles. The enhanced catalytic performance was attributed to synergistic interactions between Ni, Mo, and W and to the favorable surface morphology of the multicomponent coating, which promoted the hydrogen generation reaction. Full article
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26 pages, 12683 KB  
Article
Advanced Classification of Lithium-Ion Battery Defects Using Electrochemical Impedance Spectroscopy and Machine Learning
by Tobias G. Bergmann, Xinyang Liu-Théato, Binbin Zhu and Lea Leuthner
Batteries 2026, 12(7), 228; https://doi.org/10.3390/batteries12070228 (registering DOI) - 25 Jun 2026
Abstract
Metallic particle contaminants have been shown to have a detrimental effect on the reliability, performance and capacity of lithium-ion battery cells. In addition, they pose a significant safety risk. Typical contaminants, such as iron (Fe), copper (Cu) and aluminium (Al), often enter the [...] Read more.
Metallic particle contaminants have been shown to have a detrimental effect on the reliability, performance and capacity of lithium-ion battery cells. In addition, they pose a significant safety risk. Typical contaminants, such as iron (Fe), copper (Cu) and aluminium (Al), often enter the cell via mechanical abrasion from production equipment, as burrs during electrode cutting, or through environmental exposure during handling. In such instances, the degradation mechanisms are known to accelerate, dendrite formation is increased, and, in the most unfavourable circumstances, thermal runaway is the likely outcome. Contaminants that do not affect cell behavior during formation and the initial cycles, yet only compromise safety at a subsequent stage, are of particular concern. Affected cells are known to pass end-of-line testing and make their way into the market as latent safety risks. Consequently, there is an urgent requirement for non-destructive diagnostic methods that are capable of identifying latent defects. The issue under discussion is approached in the present paper through the utilization of an innovative methodology that integrates the distribution of relaxation time (DRT) analysis of electrochemical impedance spectroscopy (EIS) data with machine learning techniques. The objective of this integrated approach is to facilitate the detection of critically contaminated pouch cells with a high degree of sensitivity. Full article
(This article belongs to the Section Energy Storage System Aging, Diagnosis and Safety)
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20 pages, 729 KB  
Review
Molecular Mechanisms of Photobiomodulation in Retinal Diseases: Cytochrome c Oxidase, Mitochondrial Bioenergetics and Cytoprotective Signalling
by Rubens Camargo Siqueira
Int. J. Mol. Sci. 2026, 27(13), 5683; https://doi.org/10.3390/ijms27135683 (registering DOI) - 24 Jun 2026
Abstract
Photobiomodulation (PBM) is a non-invasive therapeutic strategy that uses red and near-infrared (NIR) light in the 590–950 nm range to modulate the cellular and molecular pathways involved in retinal homeostasis. At the molecular level, PBM acts primarily through photon absorption by cytochrome c [...] Read more.
Photobiomodulation (PBM) is a non-invasive therapeutic strategy that uses red and near-infrared (NIR) light in the 590–950 nm range to modulate the cellular and molecular pathways involved in retinal homeostasis. At the molecular level, PBM acts primarily through photon absorption by cytochrome c oxidase (CcO, complex IV of the mitochondrial electron transport chain), whose four metal centres—two copper (CuA and CuB) and two heme groups (heme a and heme a3)—absorb light across approximately 600–1000 nm. Photon capture promotes photodissociation of inhibitory nitric oxide (NO) from the binuclear CuB–heme a3 centre, accelerates electron transfer, restores the proton-motive force and increases ATP synthesis. These primary events trigger a coordinated molecular programme that includes (i) transient mitochondrial reactive oxygen species (ROS) bursts that activate the Nrf2/Keap1/ARE axis and upregulate phase II antioxidant enzymes (HO-1, NQO1, GCLC, SOD2, catalase, GPx); (ii) calcium- and cAMP-dependent secondary signalling that converges on PI3K/Akt, MAPK/ERK, AMPK and mTOR pathways; (iii) suppression of NF-κB-driven cytokine production (TNF-α, IL-1β, IL-6) and of NLRP3 inflammasome activation; (iv) downregulation of the HIF-1α/VEGF axis, particularly at 590 nm; (v) anti-apoptotic remodelling of the Bcl-2/Bax ratio with reduced cytochrome c release and caspase-3/9 activation; and (vi) PGC-1α/TFAM/NRF1-driven mitochondrial biogenesis, alongside restoration of fission/fusion homeostasis (Drp1, Mfn1/2, Opa1) and PINK1/Parkin-mediated mitophagy. Wavelength specificity has a defined molecular basis: 590 nm modulates VEGF signalling and RPE pump activity, 660 nm interacts with the CuB centre and enhances O2 binding at CcO, and 850 nm is absorbed by CuA and supports electron entry into complex IV. A second molecular axis is the bidirectional crosstalk between PBM and the circadian system: mitochondrial respiration, ATP turnover and CcO activity oscillate over the 24 h cycle under the control of the BMAL1/CLOCK and PER/CRY core machinery, the NAD+/SIRT1–SIRT3 axis and REV-ERBα. Preliminary preclinical and human observations suggest that NIR-induced bioenergetic and functional gains may be coupled to this rhythm, with greater benefit reported when light is delivered in the morning window (≈08:00–11:00); this time dependence should be regarded as an emerging hypothesis rather than an established clinical principle. The clinical evidence is unevenly developed across indications. It is most robust for non-exudative age-related macular degeneration, where multiwavelength PBM (590/660/850 nm; Valeda Light Delivery System) has shown disease-modifying potential in randomized controlled trials (LIGHTSITE I–III and the LIGHTSITE IIIB extension), with sustained BCVA gains and reduced incidence of geographic atrophy over 24 months and beyond. Evidence for retinitis pigmentosa, central serous chorioretinopathy and, with red-light monotherapy, childhood myopia is at present limited to small or short-term studies and remains preliminary. This narrative review synthesizes the molecular machinery engaged by PBM, integrates clinical findings across retinal diseases and discusses how chronotherapeutic delivery of light, aligned with the molecular clock, may further optimize therapeutic efficacy. Full article
(This article belongs to the Special Issue Progress in Photobiomodulation Therapy)
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32 pages, 5480 KB  
Article
Biological Activity of Copper(II) and Palladium(II) Complexes with a Tetradentate S,O-Donor Ligand
by Anita Sarić, Marina Mitrović, Ana Barjaktarević, Snežana Jovanović Stević, Biljana Petrović, Žiko Milanović, Dušan Lj. Tomović, Andriana M. Bukonjić, Djordje Petrović, Mirjana Jakovljević, Gordana P. Radić, Marina Jovanović, Irfan Ćorović, Nebojša Zdravković, Ivan Jovanović and Bojana Simović Marković
Int. J. Mol. Sci. 2026, 27(13), 5659; https://doi.org/10.3390/ijms27135659 (registering DOI) - 23 Jun 2026
Abstract
New copper(II) (C1) and palladium(II) (C2) complexes with S,O-tetradentate ligand (L) derived from thiosalicylic and thiopropionic acids were synthesized. In cell-based assays, (C1) exhibited the most pronounced activity within the tested compound series and was therefore advanced for mechanistic evaluation in 4T1 triple-negative [...] Read more.
New copper(II) (C1) and palladium(II) (C2) complexes with S,O-tetradentate ligand (L) derived from thiosalicylic and thiopropionic acids were synthesized. In cell-based assays, (C1) exhibited the most pronounced activity within the tested compound series and was therefore advanced for mechanistic evaluation in 4T1 triple-negative breast cancer cells. (C1) significantly reduced 4T1 cell viability by inducing early and late apoptosis, accompanied by mitochondrial membrane depolarization and enhanced cytochrome C release. Consistently, (C1) increased the Bax/Bcl-2 ratio, promoting a pro-apoptotic shift. In parallel, (C1) triggered autophagy, as evidenced by decreased p62 and LC3B levels, induced G0/G1 cell-cycle arrest, and suppressed proliferative signaling by downregulating Ki67, cyclin D, and phosphorylated AKT. The DNA-binding studies showed moderate to strong affinity, favoring minor groove binding, with higher affinity for (C1) than for (C2). Tryptophan fluorescence quenching indicated a strong interaction with BSA via a predominantly static mechanism, more pronounced for (C1). Molecular docking at the DNA and BSA binding sites corroborated experimental findings and suggested favorable interactions between the complexes and apoptosis-related proteins (CASP3, BAX, and BCL2). The integrated experimental and computational data identify (C1) as a biologically active compound with multimodal biological effects in vitro, supporting further structural optimization and mechanistic investigation. Full article
(This article belongs to the Special Issue Research on Metal-Based Drugs and Their Mechanisms of Action)
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22 pages, 7202 KB  
Article
Effect of Allocation and Allocation Avoidance Methods on Life-Cycle Impact Results for Tellurium Production from Copper Anode Slimes
by Ioanna Paschalidou, Kwame Awuah-Offei and Michael Moats
Sustainability 2026, 18(12), 6273; https://doi.org/10.3390/su18126273 - 18 Jun 2026
Viewed by 193
Abstract
The global transition toward green energy has increased demand for metals and intensified the need for sustainable supply sources. Tellurium (Te), an essential metal for photovoltaics technology, is produced primarily as a by-product of copper refinery slimes treatment. This study conducts a life-cycle [...] Read more.
The global transition toward green energy has increased demand for metals and intensified the need for sustainable supply sources. Tellurium (Te), an essential metal for photovoltaics technology, is produced primarily as a by-product of copper refinery slimes treatment. This study conducts a life-cycle assessment (LCA) study of Te production to investigate the effect of environmental impact allocation choices on LCA results in multi-product metal systems. A cradle-to-gate LCA model of the Te product system was developed in SimaPro v9.5.0.1 software by combining industrial data, Ecoinvent v3.7.1 datasets, and literature information. Environmental impacts were quantified using the ReCiPe v1.04 Midpoint method for a functional unit of 1 kg of refined Te. The product system’s multi-functionality was investigated using mass and economic allocation and a system sub-division method. Sensitivity analyses examined the effects of the Te concentration in anode slimes and their recovery efficiency on impact estimates. The results show that mass allocation assigns higher burdens to Te than economic allocation does. System sub-division yields significantly lower impacts than allocation procedures by attributing burdens only to Te-specific recovery processes. Higher Te grades and improved recovery efficiencies markedly reduced impact estimates. These findings demonstrate the importance of allocation choices on the LCA of by-product metals. Full article
(This article belongs to the Collection Environmental Assessment, Life Cycle Analysis and Sustainability)
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38 pages, 25629 KB  
Article
Economics and Environmental Impacts of Photovoltaic Panel Recycling in Germany
by Ramchandra Bhandari and Shazia Ahmed Ameer
Energies 2026, 19(12), 2862; https://doi.org/10.3390/en19122862 - 16 Jun 2026
Viewed by 347
Abstract
The rapid expansion of solar photovoltaic (PV) deployment has led to increasing concerns regarding end-of-life module management and the sustainability of material supply chains, where waste volumes are projected to reach 3.3–5.6 million tons by 2045. This study evaluates the environmental and economic [...] Read more.
The rapid expansion of solar photovoltaic (PV) deployment has led to increasing concerns regarding end-of-life module management and the sustainability of material supply chains, where waste volumes are projected to reach 3.3–5.6 million tons by 2045. This study evaluates the environmental and economic impact of advanced photovoltaic recycling in Germany, focusing on high-value material recovery from crystalline silicon modules. A Full Recovery of End-of-Life Photovoltaics (FRELP) pathway is developed, integrating light-pulse delamination and molten salt etching, and a comparative life cycle assessment and economic assessment framework is applied. The results indicate that advanced recycling achieves high recovery rates for silicon, silver, aluminum, copper and low-iron glass, yielding around €1174.88 per ton of panels recycled. Economic analysis shows that manufacturing PV modules from recycled materials reduces costs by approximately 60–77% compared to virgin material production, mainly due to avoided energy-intensive upstream processes. From an environmental perspective, the recycling-based pathway yields net benefits across impact categories, as avoided impacts from primary material extraction outweigh additional burdens associated with recycling. Overall, PV recycling in Europe is shown to be environmentally and economically favorable; however, technological maturity and policy constraints remain key barriers to large-scale implementation and a holistic overall recycling process, indicating the need for targeted policy support. Full article
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9 pages, 2398 KB  
Communication
A Rechargeable Zinc–Copper Voltaic Battery Built from Cost-Effective Electrodes and Electrolytes
by Jose Fernando Florez Gomez, Songyang Chang, Irfan Ullah, Juan C. Velez Reyes, Lisandro Cunci, Gerardo Morell and Xianyong Wu
Batteries 2026, 12(6), 215; https://doi.org/10.3390/batteries12060215 - 13 Jun 2026
Viewed by 306
Abstract
The zinc–copper (Zn-Cu) voltaic battery is the first battery made in human history, but the Cu2+ dissolution issue leads to the reaction’s irreversibility. To tackle this challenge, solid-state electrolytes, ion exchange membranes, and functional electrolytes have been proposed to mitigate the Cu [...] Read more.
The zinc–copper (Zn-Cu) voltaic battery is the first battery made in human history, but the Cu2+ dissolution issue leads to the reaction’s irreversibility. To tackle this challenge, solid-state electrolytes, ion exchange membranes, and functional electrolytes have been proposed to mitigate the Cu2+ dissolution; however, these approaches incur limitations like cell complexity, high cost, and anode corrosion. Herein, we develop a simple yet effective strategy to mitigate Cu2+ dissolution and build a rechargeable voltaic battery from cost-effective materials, including commercially available micro-copper powders and non-corrosive zinc acetate electrolyte. Importantly, the near-neutral Zn(Ac)2 electrolyte provides some amounts of hydroxide and facilitates the Cu2O/Cu solid–solid conversion reaction, thereby inhibiting the generation of soluble Cu2+ ions. As a result, the Zn-Cu battery exhibits a reversible capacity of ~130 mAh g−1, a feasible voltage of 0.87 V, and a stable cycling life over 100 cycles. Our work provides a feasible strategy for developing rechargeable and cost-effective Zn-Cu batteries. Full article
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21 pages, 32972 KB  
Article
Cobalt–Copper Bimetallic Mesoporous Carbon Catalyst Activated by Peroxymonosulfate for Efficient Degradation of Tetracycline
by Xueting Shi, Wei Yan, Jun Lu, Ranran Zhou, Qijie Jin, Liguo Chen, Mutao Xu, Changcheng Zhou and Haitao Xu
Catalysts 2026, 16(6), 544; https://doi.org/10.3390/catal16060544 - 12 Jun 2026
Viewed by 338
Abstract
To efficiently degrade tetracycline (TC) antibiotic pollution, cobalt-based (Co-OMCs/F) and cobalt–copper bimetallic ((Co+Cu)-OMCs/F) monolithic mesoporous carbon catalysts were synthesized using resorcinol–formaldehyde resin as a carbon precursor, with hexamethylenetetramine (HMT) and formaldehyde (CH2O) as crosslinking agents, followed by high-temperature carbonization under N [...] Read more.
To efficiently degrade tetracycline (TC) antibiotic pollution, cobalt-based (Co-OMCs/F) and cobalt–copper bimetallic ((Co+Cu)-OMCs/F) monolithic mesoporous carbon catalysts were synthesized using resorcinol–formaldehyde resin as a carbon precursor, with hexamethylenetetramine (HMT) and formaldehyde (CH2O) as crosslinking agents, followed by high-temperature carbonization under N2. The materials were characterized by XRD, SEM-EDX, HRTEM, and EPR. Key factors-metal loading, PMS concentration, initial pH, and flow rate-were investigated for their effects on TC degradation. Degradation mechanisms and stability were assessed via radical quenching and continuous-flow cycling tests. Results show optimal performance at a cobalt loading of 0.6 g. Compared to CH2O, HMT favors a three-dimensional interconnected mesoporous carbon framework with uniform metal distribution and high crystallinity. Under conditions of 25 mg/L TC, 0.33 mmol/L PMS, pH 7, and 2 mL/min flow rate, the (Co+Cu)-OMCs/F (HMT) catalyst achieved ~93% TC degradation over 9 h of continuous operation, and 95% after three reuse cycles, significantly outperforming the single-metal Cu-OMCs/F catalyst. Radical quenching and EPR identified superoxide radicals (·O2) as the dominant active species (~78% contribution), with sulfate radicals (SO4·−), hydroxyl radicals (·OH), and singlet oxygen (1O2) playing synergistic roles. The synergistic Co-Cu bimetallic effect, combined with the confinement effect of the mesoporous carbon support and HMT-induced uniform nucleation, endows the catalyst with high activity and long-term stability. This work provides a theoretical basis for designing efficient, reusable, monolithic mesoporous carbon-based PMS activation catalysts for advanced antibiotic wastewater treatment. Full article
(This article belongs to the Special Issue Green Catalytic Materials for Environmental Application)
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20 pages, 3173 KB  
Article
Plant-Mediated Fabrication of Copper-Oxide-Decorated Magnetic Nanocarriers for β-Galactosidase Immobilization: Toward Sustainable Biocatalysis in Lactose Processing
by Naif Abdullah R. Almalki
Inorganics 2026, 14(6), 159; https://doi.org/10.3390/inorganics14060159 - 12 Jun 2026
Viewed by 346
Abstract
This study reports the plant-mediated synthesis of copper-oxide-decorated magnetic iron oxide composite (CuO@Fe3O4) nanoparticles using Dolomiaea costus extract and their application as nanocarriers for β-galactosidase immobilization. The fabricated nanocomposite exhibited favorable physicochemical properties, achieving an immobilization efficiency of 83%, [...] Read more.
This study reports the plant-mediated synthesis of copper-oxide-decorated magnetic iron oxide composite (CuO@Fe3O4) nanoparticles using Dolomiaea costus extract and their application as nanocarriers for β-galactosidase immobilization. The fabricated nanocomposite exhibited favorable physicochemical properties, achieving an immobilization efficiency of 83%, with enhanced thermal and pH tolerance compared to the free enzyme. Kinetic analysis revealed a modest increase in Km and a 31% decrease in Vmax after immobilization, while maintaining 69% of the catalytic activity, confirming the system’s suitability for industrial lactose hydrolysis. Reusability and storage tests showed 79% retained activity after five cycles and 77% after 60 days at 4 °C. In milk hydrolysis, the immobilized enzyme achieved 77% conversion within 3 h, following pseudo-first-order kinetics. Biocompatibility was evaluated using HepG2 cells via the MTT assay. BDH, MDH, and ABC maintained high cell viability across the tested dilution range of 25–100% (v/v), indicating no detectable cytotoxic effect under the experimental conditions, whereas cisplatin showed marked cytotoxicity with an IC50 of 14.98 µg/mL. These findings demonstrate that the green-synthesized CuO@Fe3O4 support provides a safe, reusable, and magnetically recoverable platform for β-galactosidase immobilization, offering a promising sustainable strategy for producing lactose-free dairy products. Full article
(This article belongs to the Special Issue Sustainable Metal Catalysis for Green Chemical Transformations)
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30 pages, 3952 KB  
Article
A Mathematical Co-Design Framework for Synchronous Boost DC-DC Converters and PI Controllers Under Parasitic and Semiconductor Loss Effects
by Nikolay Hinov, Polya Gocheva and Valeri Gochev
Mathematics 2026, 14(12), 2086; https://doi.org/10.3390/math14122086 - 11 Jun 2026
Viewed by 179
Abstract
This paper proposes a mathematical co-design framework for synchronous Boost DC-DC converters and their PI voltage controllers. In contrast to the conventional sequential design approach, where the power stage is sized first and the controller is tuned afterward, the proposed method treats the [...] Read more.
This paper proposes a mathematical co-design framework for synchronous Boost DC-DC converters and their PI voltage controllers. In contrast to the conventional sequential design approach, where the power stage is sized first and the controller is tuned afterward, the proposed method treats the converter and the controller as a single coupled design problem. A nonlinear averaged model of the synchronous boost converter operating in continuous conduction mode is considered, explicitly incorporating the inductor series resistance, the capacitor equivalent series resistance, and the on-state resistances of the active switches. In addition, a simplified but physically interpretable loss model is included in order to capture inductor copper loss, capacitor ESR loss, semiconductor conduction loss, and switching loss. Based on this formulation, the joint design of the power stage and the PI controller is cast as a constrained multi-objective optimization problem whose decision variables include the inductance, capacitance, switching frequency, and controller gains. The optimization criteria account for output-voltage ripple, settling time, total losses, and current stress, while practical constraints related to duty cycle, current limits, ripple bounds, and closed-loop feasibility are enforced. The proposed framework makes it possible to compute Pareto-efficient designs and to reveal trade-offs that remain hidden under classical decoupled design procedures. Numerical case studies are structured to compare the proposed co-design strategy with a conventional sequential-design baseline. An optional technology-aware extension is also considered, allowing the influence of different semiconductor classes, such as Si, SiC, and GaN, to be assessed through technology-dependent loss and switching-frequency assumptions. The results indicate that the proposed framework provides a mathematically grounded and practically useful basis for integrated converter–controller synthesis in nonideal power electronic systems. Full article
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21 pages, 4328 KB  
Article
Reinforcement Learning-Based Policy for Haul-Truck Dispatch: A Framework for Earthmoving and Quarry Operations
by Mohsen Hatami, Ian Flood and Forough Foroutan
Buildings 2026, 16(11), 2274; https://doi.org/10.3390/buildings16112274 - 4 Jun 2026
Viewed by 285
Abstract
Truck-to-excavator assignment is a time-critical control problem in open-pit earthmoving systems (mines, quarries, and large cut-and-fill construction sites) where stochastic travel and service times, changing queues, and equipment outages continually alter the best dispatch decision. A deep reinforcement learning (DRL) dispatch policy is [...] Read more.
Truck-to-excavator assignment is a time-critical control problem in open-pit earthmoving systems (mines, quarries, and large cut-and-fill construction sites) where stochastic travel and service times, changing queues, and equipment outages continually alter the best dispatch decision. A deep reinforcement learning (DRL) dispatch policy is developed and trained using a discrete-event simulation (DES) digital twin of the Sungun copper mine haulage system. The dispatch task is formulated as a Markov decision process using state features that represent fleet locations, excavator and dump queues, and short-term congestion conditions. The resulting deep artificial neural network (DANN) policy is tuned via systematic hyperparameter optimisation and evaluated against a priority-based rule-of-thumb dispatch baseline under long-horizon operating tracks. Results show that the final trained policy improves the average production rate per truck cycle by approximately 17% while reducing avoidable waiting and maintaining stable performance over extended operation, with inference fast enough for real-time dispatch use. Model fidelity is supported by close agreement between simulated and observed daily completed-cycle counts. Robustness is assessed through controlled truck load-capacity perturbations, and scalability is examined through fleet-size sensitivity, which reveals diminishing returns as additional trucks are added under a fixed excavation–haulage configuration. Practical deployment considerations and implications for construction earthmoving logistics are discussed. Full article
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56 pages, 15811 KB  
Review
Thin-Film Solar Cells for Solar Thermal Cooling, Heating, and Energy Storage Systems: Materials, Manufacturing, and Emerging Applications
by Sunzid Hassan, Sabbir Alom Shuvo, Jarif Ul Alam, Nafiya Islam, Md Faiaz Al Islam, Yead Rahman, Iftesam Nabi, Fatima Yeasmin, Md Ashfaq Siddiquee, Ahsanul Alam Kabhi, Mehrab Hosain and M Shafiqur Rahman
Energies 2026, 19(11), 2684; https://doi.org/10.3390/en19112684 - 2 Jun 2026
Viewed by 435
Abstract
Thin-film solar cells (TFSCs) remain a cornerstone of the global transition toward renewable energy, characterized by consistent reductions in manufacturing costs and steady gains in power conversion efficiency. In addition to electricity generation, TFSCs play an important role in advanced solar thermal cooling, [...] Read more.
Thin-film solar cells (TFSCs) remain a cornerstone of the global transition toward renewable energy, characterized by consistent reductions in manufacturing costs and steady gains in power conversion efficiency. In addition to electricity generation, TFSCs play an important role in advanced solar thermal cooling, heating, and energy storage systems, where their tunable optical absorption, low thermal mass, and flexibility enable integration with photovoltaic–thermal (PV/T) collectors, thermally driven cooling cycles, and hybrid thermal–electrical storage architectures. This paper provides a comprehensive review of prominent TFSC technologies, including copper indium gallium selenide (CIGS), cadmium telluride (CdTe/CdS), amorphous silicon (a-Si), copper zinc tin sulfide (CZTS), organic photovoltaics (OPVs), and metal halide perovskite solar cells (PSCs), with a focus on their material structures, performance specifications, and current efficiency benchmarks. Compared to state-of-the-art reviews, this article distinguishes itself by addressing next-generation innovations, cross-domain solar thermal–photovoltaic applications, and economic analysis. Specifically, the integration of machine learning and simulation-based material dynamics is examined to accelerate material discovery, process optimization, and the characterization of novel TFPV components relevant to coupled thermal–electrical energy systems. Furthermore, the study explores how additive manufacturing is transforming the industry through the development of high-efficiency electrodes, electrohydrodynamic atomization for thin-film deposition, and the fabrication of flexible solar arrays suitable for thermally integrated and building-scale energy systems, including space applications. By integrating advancements in module efficiency, scalable manufacturing approaches, and techno-economic analysis, this paper positions TFSCs as sustainable, resource-abundant technologies essential for next-generation solar thermal cooling, heating, and energy storage infrastructures. Full article
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22 pages, 4352 KB  
Article
Physicochemical Properties of Pristine and Pyrolyzed CNO Synthesized via Wick Pyrolysis
by Abirami Srinivasan, Avanottingal Bhaskaran Prasanth, C. N. Shyam Kumar and Amrtha Bhide
C 2026, 12(2), 48; https://doi.org/10.3390/c12020048 - 29 May 2026
Viewed by 266
Abstract
Carbon nano-onions (CNOs) were synthesized at ambient conditions using the wick-pyrolysis technique with ghee as a precursor. A high-purity copper substrate produced unique CNOs, differing from those obtained with other metals. To purify the nanoparticles, they underwent treatment with a solvent mixture of [...] Read more.
Carbon nano-onions (CNOs) were synthesized at ambient conditions using the wick-pyrolysis technique with ghee as a precursor. A high-purity copper substrate produced unique CNOs, differing from those obtained with other metals. To purify the nanoparticles, they underwent treatment with a solvent mixture of acetone and deionized water or were pyrolyzed at 1000 °C under nitrogen without a catalyst. Various characterization techniques, including X-ray diffraction (XRD), Field Emission Scanning Electron Microscopy (FE-SEM), High-Resolution Transmission Electron Microscopy (HR-TEM), and Raman Spectroscopy, confirmed the successful formation of CNOs. Energy Dispersive Spectroscopy (EDS) and Elemental analysis (CHN) indicated the presence of oxygen in treated CNOs. X-ray photoelectron spectroscopy (XPS) revealed binding energies linked to C-O and C=O bonds. The average particle size was found to be 30–50 nm, with some agglomeration in pyrolyzed samples. A significant increase in surface area from 79.7 m2/g to 261.8 m2/g was observed, along with changes in pore radius and volume via Brunauer–Emmett–Teller (BET) analysis. Water contact angles on the CNO surface were measured at 125° and 138°, indicating hydrophobicity. Electrochemical tests on CNO-based composite electrodes yielded a specific capacitance of 109.7 F/g with 96% capacity retention over 5000 cycles. Full article
(This article belongs to the Section Carbon Materials and Carbon Allotropes)
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44 pages, 4883 KB  
Review
Gold Recovery Beyond Ores: Sources, Processes, Challenges, and Prospects
by Jovana Djokić, Stefan Nikolić, Stevan Dimitrijević, Shuiping Zhong and Željko Kamberović
Metals 2026, 16(6), 595; https://doi.org/10.3390/met16060595 - 29 May 2026
Viewed by 687
Abstract
Gold (Au) is a strategically critical metal whose technological relevance and increasing demand contrast with the long-term decline in primary ore grades. This review discusses gold recovery from primary ores providing the metallurgical and technological baseline for the comparative evaluation of unconventional Au-bearing [...] Read more.
Gold (Au) is a strategically critical metal whose technological relevance and increasing demand contrast with the long-term decline in primary ore grades. This review discusses gold recovery from primary ores providing the metallurgical and technological baseline for the comparative evaluation of unconventional Au-bearing resources. Emphasis is placed on electronic waste and copper anode slimes as highly valuable secondary raw materials containing gold concentrations comparable to, or exceeding, those in natural deposits. The review examines the origin, chemical and mineralogical characteristics, impurity profiles, and processing routes associated with these materials, including conventional and emerging pyro-, hydro-, and biometallurgical approaches. Material-specific constraints, matrix complexity, recovery efficiency, process limitations, and environmental aspects are discussed in relation to process applicability and technological feasibility. Particular attention is given to the differences between geologically constrained primary ores and heterogeneous secondary Au-bearing materials, whose engineered and continuously evolving compositions influence recovery strategies, limiting the direct application of conventional routes to secondary resources. Finally, the review highlights that primary ores remain the dominant source of global Au production, whereas secondary resources currently represent a complementary component, and outlines key challenges and future directions relevant to the broader utilization of these materials. Full article
(This article belongs to the Special Issue Advances in Mineral Processing and Hydrometallurgy—4th Edition)
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17 pages, 2681 KB  
Article
Fast Driving Cycle Efficiency Optimization of Interior Permanent Magnet Synchronous Machines Considering PWM-Induced Harmonic Losses
by Runqing Ni, Chengxin Zhong and Sa Zhu
Machines 2026, 14(6), 599; https://doi.org/10.3390/machines14060599 - 27 May 2026
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Abstract
A multi-objective optimization framework is developed in this work to improve the driving cycle efficiency of IPMSMs, into which a fast-computational approach for PWM-induced harmonic losses is embedded. At a set of characteristic operating points, iron losses are first evaluated under sinusoidal current [...] Read more.
A multi-objective optimization framework is developed in this work to improve the driving cycle efficiency of IPMSMs, into which a fast-computational approach for PWM-induced harmonic losses is embedded. At a set of characteristic operating points, iron losses are first evaluated under sinusoidal current source (SCS) excitation using Computationally Efficient Finite Element Analysis (CE-FEA), while a Time-Stepping Finite Element Analysis (TS-FEA) spanning one quarter of the electrical period provides the copper losses. For scenarios where the machine is driven by a pulse-width modulation (PWM) voltage source inverter, the harmonic losses arising from modulation are quickly assessed through a small-signal time-harmonic finite element method (THFEA)-based model. The resulting optimization procedure seeks a trade-off between two conflicting goals: minimizing overall losses and reducing material cost. Given an equal cost level, incorporating PWM-related harmonic losses into the design loop cuts down the total loss by 3.11% relative to a baseline that only considers SCS-supply losses. The extra computational burden amounts to 17 h, representing a time rise of roughly 22.65%. Full article
(This article belongs to the Section Electrical Machines and Drives)
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