Abstract To address the conductivity and volume-expansion bottlenecks of MoS2 anodes, we report a scalable, binder-free MoS2@TiO2 heterojunction fabricated by an in situ two-stage magnetron sputtering strategy. Vertically aligned MoS2 nanosheets are conformally capped with an amorphous, oxygen-vacancy-rich TiO2 skin. The electrode retains 507 mAh g–1 with ∼100% Coulombic efficiency after 500 cycles at 2 A g–1 and delivers 1135 mAh g–1 even at 20 A g–1. XPS/UPS quantifies high-density oxygen vacancies (Ovs) in TiO2, while DFT reveals these vacancies lower Li+ adsorption energy to −4.003 eV and drive electron accumulation into MoS2. EIS verifies a charge-transfer resistance of only 22.4 Ω, and CV confirms pseudocapacitive-dominated kinetics. DOS/band-alignment analysis substantiates that Ovs generate a built-in electric field pointing from TiO2 to MoS2, which promotes interfacial charge redistribution and accelerates Li+ adsorption and diffusion. These atomistic insights into the interfacial electronic structure modulation highlight an industrially compatible interface-engineering route for fast-charging lithium-ion anodes.
Abstract Carbon materials are widely used in electrochemical technologies due to their tunable structure and chemical versatility. Hydrothermal carbonization (HTC) of biomass offers a sustainable synthesis route, yet quantitative links between processing conditions and material properties remain unclear. In this study, glucose-derived hydrochars were produced by systematically varying HTC temperature (180–210 °C), residence time (0.5–3 h), and precursor concentration. Increasing reaction severity promoted carbon retention in the solid phase while reducing soluble intermediates. Spectroscopic analyses (FTIR, XPS, Raman) revealed progressive heteroatom removal and development of sp2 carbon domains. Subsequent pyrolysis further enhanced structural ordering and reduced oxygen functionalities without altering morphology. Electrochemical measurements showed stable double-layer capacitance for pristine hydrochars (66 μF cm–2), with moderate improvement after pyrolysis (79 μF cm–2). Oxygen evolution reaction kinetics remained typical of metal-free carbons. Overall, this work establishes clear correlations among HTC conditions, carbon partitioning, structural evolution, and electrochemical behavior, supporting rational design of biomass-derived carbon materials.
Abstract Comprehensive characterization of multiscale pore structures in unconventional reservoirs is crucial for evaluating gas storage, migration pathways, and production potential. This study presents an integrated, multimethod investigation of Lower Jurassic low-rank coal, low-maturity shale, and tight sandstone from the Fukang area, Junggar Basin, China. High-pressure mercury intrusion porosimetry (HMIP), low-temperature N2/CO2 adsorption, and low-field nuclear magnetic resonance (LF-NMR) were applied to quantify pore geometry, connectivity, and heterogeneity across nano–micro–macro scales. FHH and Brooks–Corey models were applied to evaluate pore heterogeneity and connectivity. Results reveal marked lithology-dependent contrasts. Shale is dominated by micropores (∼50%) with limited connectivity, functioning primarily as an adsorption reservoir. Coal exhibits a high proportion of medium-to-large pores (macropores ∼42.7%), comprising well-connected through/linked pores and ink-bottle geometries, facilitating both gas storage and migration. Tight sandstone presents multimodal pore-throat distributions, ranging from well-connected, low-displacement-pressure bodies to fine-throat, poorly connected bodies. LF-NMR and HMIP consistently indicate that coal and well-connected sandstones dominate fluid transport, whereas shale micropores contribute minimally to mobility. Fractal analysis quantifies multiscale heterogeneity: fractal parameters obtained from low-relative-pressure regions (D1) are highest in coal (∼2.76), intermediate in tight sandstone (∼2.66), and lowest in shale (∼2.57), while fractal parameters obtained from high-relative-pressure regions (D2) peak in tight sandstone (∼2.72), reflecting complex internal pore-throat networks. Brooks–Corey analysis reveals that wide-throat complexity primarily controls permeability. This multitechnique, fractal-based framework establishes a robust, cross-lithology methodology for evaluating pore connectivity, storage–flow partitioning, and production potential. The results offer transferable insights for continental unconventional reservoirs with heterogeneous pore systems.
Abstract This study investigates the temperature-dependent corrosion of bismuth-based low-melting alloys (Sn-58Bi and Sn-65.7Bi-2.3Sb) in simulated geological CO2 storage environments. Experiments were conducted in a high-pressure autoclave, with post-corrosion analysis including gas breakthrough tests, digital microscopy, and XPS. Results show that corrosion depth and rate increase with temperature. When temperature rose from 30 °C to 90 °C, the corrosion-related degradation extent of cement plugs increased from 15.2 mm to 31.6 mm, significantly higher than the increases for Sn-58Bi (0.35 to 0.65 mm) and Sn-65.7Bi-2.3Sb (0.11 to 0.29 mm). The degradation mechanisms of the two types of sealing materials were fundamentally different: class G cement plugs mainly experienced CO2-induced bulk degradation within the cement matrix, resulting in structural deterioration, whereas bismuth-based alloy plugs exhibited limited bulk corrosion and were primarily affected by localized degradation at the alloy–casing interface. XPS identified (BiO)2CO3 as the primary corrosion product. Corrosion impaired sealing integrity: after 90 °C exposure, the breakthrough pressure of cement dropped by 73%, compared to only 2.4% for Sn-58Bi and 0.6% for Sn-65.7Bi-2.3Sb. The study concludes that corrosion accelerates with temperature in CO2-rich environments, and Sn-65.7Bi-2.3Sb exhibits superior corrosion resistance to Sn-58Bi, providing experimental insights into the corrosion resistance and sealing performance evolution of these alloys under simulated CCUS conditions.
Abstract Significant discrepancies in in situ gas content and occurrence characteristics exist among different siliceous shale subfacies of the Wufeng–Longmaxi Formation, yet the underlying controlling mechanisms remain poorly understood, particularly in normal-pressure shale gas reservoirs. This study systematically investigated the gas-bearing heterogeneity and its dominant controls in the Anchang syncline, a representative normal-pressure block in northern Guizhou. A suite of laboratory analyses, including TOC determination, XRD mineralogy, FE-SEM, low-temperature N2 adsorption, and high-pressure methane adsorption, were employed. The results indicate that siliceous shales are divided into mixed-siliceous shale facies (S-2) and clay-bearing siliceous shale facies (S-4). S-2 is dominated by organic matter pores, exhibiting a higher total pore volume and specific surface area. In contrast, S-4 features abundant clay-related inorganic pores with underdeveloped organic pores. S-2 demonstrates superior methane adsorption capacity, with an average maximum absolute adsorption capacity of 3.676 cm3/g compared to 3.456 cm3/g for S-4. The TOC content and hydrophilic clay mineral proportion are the primary controls on adsorption capacity. SDR model results reveal that S-2 has a higher average in situ total gas content of 4.293 cm3/g with an adsorbed gas ratio of 79.27%, while S-4 averages 3.622 cm3/g with an adsorbed gas ratio of 87.47% and limited free gas. Gas-bearing properties are synergistically controlled by TOC, pore structure, mineral composition, and water saturation. Crucially, the higher water saturation of S-4, driven by its clay-rich composition, allows water to easily invade pores under normal-pressure conditions, weakening capillary sealing and causing a far more severe free gas loss than in S-2. Integrated analysis reveals that S-2 displays superior gas-bearing properties and more favorable occurrence conditions, positioning it as the prime exploration target in the Anchang syncline.
Abstract Zika virus (ZIKV), a mosquito-borne flavivirus, has emerged as a public health concern. Although asymptomatic or mild febrile illness in adults, ZIKV infection can lead to severe outcomes in pregnant women, including fetal microcephaly and congenital Zika syndrome. A hallmark of ZIKV pathogenesis is the virus-induced remodeling of the endoplasmic reticulum into specialized replication organelles (ROs), which function as spatially organized hubs that actively couple viral RNA synthesis with the host translation machinery. These specialized ROs enhance viral genome amplification, prioritizes viral mRNA translation, and minimizes the cytosolic exposure of immunostimulatory viral double-stranded RNA intermediates. This review explores how this spatial coupling underlies the unique tropism of ZIKV towards neural progenitor cells, a characteristic that sets it apart from other neurotropic flaviviruses. In particular, ZIKV adaptations that simultaneously promote viral replication and disrupt host neurogenesis are critically discussed.
Abstract Hydrogels possess exceptional biocompatibility and have therefore been widely utilized in biomedical applications. However, their broader development is often constrained by limited intrinsic functionality and inadequate dynamic responsiveness. Metal complexes offer a promising solution to these limitations by introducing dynamic coordination interactions, catalytic properties, and multi-stimuli responsiveness, enabling new avenues for hydrogel functionalization. This review begins with a systematic examination of four principal strategies for integrating metal complexes into hydrogel matrices: physical embedding, chemical grafting, coordination-based cross-linking, and in situ complex formation. This review methodically compares these four integration strategies rather than treating them as interchangeable routes. Emerging evidence indicates that incorporating metal complexes can endow hydrogels with enhanced biomedical capabilities, including anti-inflammatory, anticancer, and antibacterial activities. Despite these advances, several challenges persist, particularly with respect to biocompatibility, long-term structural and functional stability, and scalable manufacturing. Consequently, we propose the implementation of application-specific design criteria and a translational framework covering metal pharmacokinetics, biodegradation, manufacturing reproducibility, and long-term safety. Future research is therefore expected to focus on the development of biomimetic, multi-responsive hydrogel systems that support precision therapeutics and regenerative medicine. This analysis distinguishes metal-coordinated hydrogels from metal-free hydrogels and unconfined metal nanomaterials, while identifying the evidence still required for clinical development.
Abstract Carbapenem-resistant Pseudomonas aeruginosa (CR-PA) has been designated a “priority” pathogen by the World Health Organization, calling for the development of new control strategies. However, no such new drugs are currently available. In this study, we restored bacterial sensitivity to meropenem through a metabolic state-reprogramming approach. Glutamate was identified as the key reprogramming metabolite that converts an antibiotic-resistant metabolic state to an antibiotic-sensitive state in both lab-evolved and clinically isolated CR-PA. This reprogramming leads to increased meropenem uptake, which overcomes drug efflux and enzymatic hydrolysis, elevates intracellular drug concentrations, and restores meropenem killing efficacy in vitro and in vivo. Mechanistically, glutamate metabolic flux enters fatty acid biosynthesis via the pyruvate cycle, elevating lauric acid levels. Increased lauric acid enhances outer membrane permeability, thereby raising intracellular meropenem accumulation. Glutamate is a nutritional amino acid, and the dose used in this study is lower than that in routine clinical use. Collectively, these findings provide an effective, convenient, and economical approach to restore meropenem killing efficacy against CR-PA.
Abstract The integration of ion-tuned waterflooding with surfactant flooding has emerged as a promising strategy for enhanced oil recovery (EOR), yet the mechanisms governing ion-surfactant interactions at fluid–fluid and fluid–solid interfaces remain insufficiently understood. This study systematically investigated the effects of divalent cations (Ca2+ and Mg2+) on the interfacial behavior and displacement performance of cationic, zwitterionic, and nonionic surfactants. Surfactant solutions were prepared with low-salinity (1000 mg/L) and high-salinity (50000 mg/L) CaCl2 and MgCl2 brines. Interfacial tension, dilatational modulus, and contact angle measurements were conducted to characterize fluid–fluid and fluid–solid interactions, followed by pore-scale displacement experiments in microfluidic devices containing dead-end pore structures. The results demonstrated that the influence of divalent cations strongly depended on the surfactant type and salinity. For the cationic surfactant, high-salinity CaCl2 significantly reduced the IFT, whereas MgCl2 exhibited a weaker IFT-reduction effect. Divalent cations progressively decreased the dilatational modulus of the cationic surfactant interface, indicating an enhanced interfacial mobility. In contrast, the zwitterionic surfactant exhibited minimal changes in IFT but showed an increased dilatational modulus upon salt addition, suggesting the formation of a more rigid interfacial film through ion-mediated intermolecular interactions. The nonionic surfactant displayed limited sensitivity to divalent cations with only moderate variations in IFT and interfacial rheology. Wettability measurements revealed that divalent cations altered the adsorption behavior of the cationic surfactant on quartz surfaces, while their influence on the zwitterionic and nonionic surfactants was comparatively weak. Microfluidic displacement experiments showed that higher oil recovery correlates with a balance between interfacial tension and dilatational modulus, particularly when their values are comparable. Statistical analysis further identified salinity as the dominant factor controlling oil recovery and revealed a significant synergistic interaction between selected surfactant species and salinity with the largest effect size. These findings provide mechanistic insights into ion-surfactant interactions and offer guidance for the design and optimization of ion-tuned surfactant flooding processes for enhanced oil recovery.
Abstract Plant phenolics represent a prospective source of renewable antifungal drugs, yet the molecular mechanisms underlying their activity within the structurally varied phenolic components of natural products like wood vinegar remain ambiguous. Nine phenolic compounds from corncob (Zea mays) and Areca catechu wood vinegars, encompassing the phenol, guaiacol, syringol, and benzenediol categories were examined by in silico methods. Geometries and global reactivity descriptors were derived using density functional theory at the B3LYP-D3BJ/def2-TZVP/CPCM(water) level, homolytic O–H bond dissociation enthalpies (BDEs) and phenoxyl-radical spin-density distributions were calculated to evaluate and elucidate radical-scavenging capacity, while consensus lipophilicity (log P) was estimated to assess membrane permeability. To establish the reactivity trend on a quantitative and transferable basis, the dataset was expanded to include 12 para-, meta-, and ortho-substituted phenols (totaling 21 compounds), the O–H bond dissociation energy in the para-series exhibits a linear correlation with the Hammett constant σ+ (ρ ≈ +8.3 kcal mol–1, r = 0.987). Computed bond dissociation energies (BDEs) were compared with experimental literature values (phenol, 83.2 vs 86.7 ± 0.7 kcal mol–1), validating a consistent B3LYP deviation that neutralizes in the relative assessments upon which the analysis depends. The initial O–H bond dissociation energies for the nine natural compounds varied between 73.7 and 83.2 kcal mol–1, with phenol exhibiting the lowest reactivity and the two benzenediols demonstrating the highest reactivity. log P and BDE exhibited statistical independence (r = 0.15), establishing two orthogonal axes of structure-activity, however the Hirshfeld oxygen spin population of the phenoxyl radical showed a strong correlation with BDE (r = 0.911), indicating that spin delocalization is the underlying physical cause of the observed reactivity trend. Docking with Candida albicans sterol 14α-demethylase (CYP51, PDB 5TZ1) revealed phenolic affinities ranging from −5.0 to −7.6 kcal mol–1, which are inferior to the clinical azole fluconazole (−8.4 kcal mol–1) and the native inhibitor VT-1161 (−12.2 kcal mol–1), the affinity correlated with log P (r = −0.76) but not with BDE, suggesting that direct inhibition of CYP51 is at best a secondary factor. The diminished second O–H bond dissociation energies of benzenediols facilitate a quinone redox cascade that, when measured against a peroxyl reference bond, categorizes the phenols into radical-terminating monophenols and redox-cycling propagators. The framework offers a structural justification for the antifungal properties of lignin-derived phenolics at the individual component level and emphasizes the unexploited low-BDE/high-log P area as a focus for enhancement.
Abstract This study evaluated the mechanical performance, contaminant release, and life-cycle impacts of recycled plastic blocks manufactured from beach-collected and facility-sourced plastic waste. Four formulations combining polyethylene terephthalate, high-density polyethylene, low-density polyethylene, sand, and glass were evaluated. Unweathered blocks had compressive strengths between 20.6–24.3 N/mm2, suitable for paving applications; however, higher plastic fractions led to lower strength and higher porosity. UV weathering reduced strength by 6–12% and increased metal leaching by up to ∼400%. Per- and polyfluorinated concentrations peaked at 13.8 ng/L; concentrations decreased slightly after weathering due to polymer photo-oxidation and embrittlement that enhanced sorption capacity and retention. Formulations with lower plastic content (∼33%) had higher strength and lower leaching. Life-cycle assessment identified extrusion and waste-plastic processing as dominant contributors to climate change (0.12 kg CO2-eq/kg block) and particulate matter (0.42 x 10–3 kg PM10-eq/kg block), driven by fossil-based energy use and process emissions. Blocks with higher plastic ratios exhibited greater environmental burdens, matching leaching trends. These findings revealed that incorporating waste plastics into construction materials can support waste management and infrastructure, but durability, contaminant release, and processing emissions are sensitive to the formulation. Optimizing plastic-to-aggregate ratios and improving processing efficiency can improve durability while reducing environmental and health risks.
Abstract Leishmaniasis is a neglected disease that affects around two million people every year. Current treatments are often highly toxic or prone to resistance, underscoring the urgent need for new therapeutic strategies. PROTACs may offer a promising alternative, as they can potentially mitigate both toxicity and resistance. However, very little is known about the ubiquitin–proteasome system (UPS) in Leishmania. Notably, only two E3 ligases containing a CULT domain have been identified so far, and none carrying a von Hippel–Lindau (VHL) domain─the classical E3 ligase used by clinically advanced PROTACs. In this work, we take an important step toward understanding the UPS in Leishmania, and we propose that in this organism the UbC4 E2 enzyme, rather than an E3, may be directly exploited to develop a PROTAC able to engage a protein of interest. Here, we report the biochemical and structural characterization of the Leishmania major ubiquitin-conjugating enzyme 4 (UbC4). Through a fragment screening campaign, we identified 10 fragments binding to distinct cavities on UbC4. Among these, five interact with the same noncatalytic pocket that is poorly conserved in humans, while one fragment binds near the catalytic cysteine. Using DeepFrag predictions and molecular docking, we explored fragment elongation strategies to enhance affinity for their respective binding sites, with the goal of guiding the development of E2-recruiting PROTACs or UPS inhibitors for the treatment of leishmaniasis.
Abstract Flavonoid-mediated inhibition of xanthine oxidase (XO) is well established at the empirical level; however, while molecular docking, MD, and MM-PBSA/MM-GBSA methods have been widely applied, the quantum-mechanical origin of the structure–activity relationship at the molybdenum cofactor (MoCo) remains unresolved. Hybrid QM/MM calculations (B3LYP/def2-SVP) on five dietary flavonoids bound to the MoCo active site of bovine XO (50 snapshots total) revealed that all five exhibit net charge redistribution at the MoCo interface, with the magnitude varying nearly 9-fold. The charge-redistribution descriptor |CTlig| correlated with Ki (r = – 0.922, p = 0.026; Spearman ρ = – 1.000), and Hirshfeld charge analysis independently confirmed the Mulliken-derived ranking (r = 0.942, p = 0.017), while representative def2-TZVP calculations preserved the principal compound hierarchy (Spearman ρ = 0.900), supporting robustness to both charge partitioning and basis-set effects. Frontier orbital analysis links the observed structure–activity relationship to the saturated C2–C3 bond of naringenin, which interrupts π-conjugation and limits electronic communication toward the MoCo environment. The electrostatic interaction energy further correlated with Ki (r = – 0.890, p = 0.043), whereas total interfragment contact density showed no correlation, indicating that within this five-compound series, inhibitory potency was more closely associated with charge-redistribution magnitude and electrostatic interaction than with the interfragment contact-density descriptor.
Abstract Colossal permittivity (In,Nb) codoped TiO2 ceramics are promising for microelectronic applications but suffer from high low-frequency dielectric loss primarily due to leakage currents across grain boundaries. This work demonstrates that Zr4+ doping at Ti-sites in (In0.5Nb0.5)0.05Ti0.95O2 effectively mitigates this issue. A series of (In0.5Nb0.5)0.05Ti0.95-xZrxO2 (x = 0–0.20) ceramics were synthesized via solid-state reaction. Zr4+ incorporation refines grain size from ∼56.1 μm (undoped) to ∼2.5 μm (x = 0.20) and promotes the precipitation of an insulating ZrTiO4 secondary phase at grain boundaries for compositions with x ≥ 0.10. These microstructural modifications synergistically enhance the grain boundary resistance, which peaks at 10.50 × 106 Ω·cm for the x = 0.10 composition, nearly an order of magnitude higher than the undoped ceramic. Consequently, the low-frequency dielectric loss is significantly reduced, with the x = 0.10 composition sintered at 1450 °C exhibiting a minimal loss tangent. Complex impedance analysis reveals the introduction of a new interfacial polarization associated with the ZrTiO4/INTO phase boundaries. XPS analysis confirms that Zr doping suppresses oxygen vacancy concentration without altering the Ti3+/Ti4+ ratio crucial for electron-pinned defect dipoles. The optimized composition (x = 0.10) also shows improved nonlinear coefficient (α = 2.8) and breakdown field (Eb = 530 V/cm), alongside stable low loss (tanδ < 0.05) over a broad temperature range at 1 kHz. This study presents a viable defect-engineering strategy utilizing Zr4+ doping to achieve low-loss colossal permittivity in (In,Nb) codoped TiO2-based ceramics for practical applications.
Abstract Cystic fibrosis (CF) lung infections are recurrent and frequently associated with multidrug-resistant bacteria, limiting the efficacy of the currently available antibiotic therapies. Bacteriophages have emerged as a promising alternative; however, their clinical translation is constrained by their limited stability and inefficient delivery within the airway microenvironment. Here, oleic acid-modified oligochitosan (OCS-OA) nanoparticles were developed as controlled-release nanocarriers to promote bacterial clearance during infection. Three OCS-OA formulations (10, 20, and 30% OA substitution) were modified via an amidation reaction and confirmed by attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR). Surface tension analysis demonstrated the amphiphilic behavior and self-assembly of the modified oligosaccharides into micelle-like nanostructures. The bacteriophage (vB_Eco_K-02) was efficiently encapsulated (>90%), and the resulting formulations were characterized by scanning transmission electron microscopy (STEM), atomic force microscopy (AFM), dynamic light scattering (DLS), and ζ-potential. Formulations prepared with 10 and 20% OCS-OA preserved phage lytic activity against a clinical Escherichia coli strain isolated from CF patients, while the 30% formulation showed reduced activity, suggesting restricted phage release at a higher hydrophobic content.
Abstract Layered Aurivillius ferroelectrics offer a route to multifunctional band-gap engineering, yet the role of oxygen vacancies in band-edge reconstruction in Fe/Co-modified compositions remains poorly resolved. Here, oxygen annealing of Bi3.25La0.75Ti2.60(Fe0.50,Co0.50)0.40O12 (BLFC4) ceramics widens the optical band gap by 63%, from 1.35 eV (as-sintered) to 2.20 eV after 10 h of treatment, accompanied by a 5-fold drop in non-lattice oxygen (22.11% → 4.12%) and a reduction in Ti3+ from 42.68 to 10.47%, as quantified by X-ray photoelectron spectroscopy. Concurrently, X-ray diffraction reveals a decrease in octahedral tilt from 19° to 4°, while Raman spectroscopy shows up to 74% narrowing of B-site vibrational modes, together signaling systematic defect healing accompanied by a visible color change from black to light gray. Density functional theory rationalizes this behavior through a site-dependent vacancy mechanism: vacancies adjacent to Co-centered octahedra collapse the band gap toward a near-metallic state by introducing Co 3d states at the Fermi level, whereas vacancies near Fe leave the wide semiconducting gap intact. These combined results identify oxygen vacancy concentration rather than cation co-doping alone as the dominant lever controlling band-gap width, providing a quantitative, mechanistic framework for engineering Aurivillius ferroelectrics toward optoelectronic and photovoltaic applications.
Abstract Titanium dioxide–cobalt ferrite functionalized sugarcane bagasse biochar (SBC/TiO2–CoFe2O4) was developed as a multifunctional adsorbent for arsenate [As(V)] removal from water. While numerous binary TiO2-biochar or magnetic biochar systems have been reported, limited studies have explored the synergistic integration of both TiO2 and CoFe2O4 on a biochar matrix, particularly for arsenate removal under alkaline conditions. The material was synthesized via the sol–gel approach using sugarcane bagasse biochar pyrolyzed at 450 °C. Its adsorption performance toward arsenate was systematically evaluated at pH 8.5, selected due to its relevance to alkaline arsenic-contaminated groundwater and its proximity to the point of zero charge (PZC ≈7.8) of the composite. Surface and structural analyses using FTIR, SEM, and EDS provided evidence for the successful deposition of TiO2–CoFe2O4 particles onto the biochar matrix. Under the optimized adsorption conditions (0.1 g adsorbent, initial As(V) concentration of 2 mg L–1), the composite achieved an experimental equilibrium adsorption capacity of 0.39 mg g–1, while 87.3% arsenic removal was obtained after 24 h of contact time. The adsorption kinetics followed the pseudo-second-order model. Nonlinear isotherm fitting indicated best overall agreement with the Redlich–Peterson model (R2 = 0.669, AIC = −18.32), consistent with adsorption on an energetically heterogeneous composite surface; the Langmuir theoretical maximum capacity is reported as qmax = 0.526 mg g–1 for isotherm characterization purposes. Thermodynamic analysis confirmed a spontaneous (ΔG° < 0), endothermic (ΔH° > 0), entropy-driven adsorption process. ICP-OES analysis of the regenerant further demonstrated minimal Fe, Co, and Ti release (≤0.055% of the nominal metal content over four regeneration cycles), confirming high structural stability during repeated reuse. Overall, the SBC/TiO2–CoFe2O4 composite demonstrated promising multifunctionality by combining moderate adsorption capacity, magnetic recoverability, and reusability under environmentally relevant dilute conditions rarely tested in prior composite-biochar studies, highlighting its laboratory-scale potential as a sustainable biochar-based system for arsenate remediation in alkaline aqueous environments. Although phosphate competition experiments confirmed the expected inhibitory effect of competing oxyanions, further evaluation under complex natural groundwater conditions is warranted prior to field application.
Abstract The upstream biopharmaceutical processes of monoclonal antibody (mAb) production generate high-dimensional and irregularly sampled time-series data with many missing values, which can limit the robustness and reusability of data-driven models. In this study, a data-driven workflow has been developed for a previously published industrial fed-batch dataset for the mAb production process. The workflow provides comprehensive data analysis from data cleaning and imputation through model benchmarking and interpretability to enable soft sensing and predictive modelling of mAb bioreactors. Initially, the missing value imputation and their evaluation were carried out using eight supervised machine learning (ML) regressors with temporally engineered time-dependent features. Light gradient boosting machine (LightGBM) provided the best imputed data among the eight ML models and was used as the imputation model for all the variables. Compared with a previously published dual-hybrid imputation method, the LightGBM-based imputation pipeline preserved all observed measurements exactly. It reproduces more accurately both marginal distributions and the multivariate geometry of the data. Using this imputed dataset, thirty-four single and stacked ML models were benchmarked for two industrially relevant tasks. These were used for (i) pointwise soft sensing of the mAb titer using concurrent process variables and (ii) early-stage prediction of final mAb titer using data from 1–7 days. Nonlinear tree-based ensembles achieved test R2 up to 0.98 for soft sensing and 0.93 for early prediction as compared to linear and kernel-based models. However, stacked ensembles provided modest but consistent gains in accuracy and robustness over the best single tree-based ensembles. Finally, permutation variable importance, Shapley additive explanations, and partial dependence analysis showed that elapsed culture time, total cell density, culture volume, glutamine, and glutamate are the most important variables of the predicted titer, whereas tightly controlled variables such as glucose and pH contribute little within the studied operating range. This is the first study that combined modern ML-based imputation, extensive model benchmarking, and explainable artificial intelligence on an industrial mAb dataset to develop both soft sensors and early prediction models. Overall, the workflow offers a simple, reusable, and explainable framework for handling missing data and building soft sensors in industrial mAb upstream development with the potential to reduce analytical burden, speed up feedback, and support data-driven decision-making in mAb upstream processes.
Abstract Aqueous zinc batteries have become an attractive alternative for energy storage due to their low cost, safety, and low toxicity compared to traditional lithium-ion batteries, which suffer from safety concerns. However, they are limited by the lack of high-performance, stable cathodes. Herein, we report the electrochemical study of iron phthalocyanine-reduced graphene oxide hybrid materials as cathodes for aqueous zinc batteries. The prepared materials had a voltage of 1.2 V and displayed high cyclic stability with a capacity retention of over 70% after 2500 cycles and a high-rate performance up to 2000 mA/g, which represents an improvement compared to bare iron phthalocyanine, highlighting the positive effect of the incorporation of reduced graphene oxide to prepare a hybrid. Furthermore, incorporating fluorine into the phthalocyanine ring led to improved battery performance, which highlights the positive effect of tuning the phthalocyanine ring for the design of high-performance phthalocyanine-based cathodes for aqueous zinc-ion batteries.
Abstract Green synthesis has emerged as a sustainable alternative for preparing nanostructured electrocatalysts using renewable biological resources. In this work, NiO nanoparticles were synthesized using an ethanolic extract of Sargassum sp. as a biogenic mediator, and the influence of calcination temperature (300, 500, and 700 °C) on their physicochemical and electrocatalytic properties was systematically investigated. X-ray diffraction confirmed the formation of NiO cubic phase and showed an increase in crystallite size with increasing calcination temperature. FTIR, Raman, XPS, and EPR analyses revealed temperature-dependent changes in surface composition and defect chemistry, including mixed Ni2+/Ni3+ species and oxygen-vacancy-related centers. EPR signals at g ≈ 2.0005–2.0006 are assigned to F+-type centers. Electrochemical measurements in 1.0 mol L–1 KOH showed that NiO-300 exhibited the highest OER activity, requiring an overpotential of 352 mV to reach 10 mA cm–2, compared with 368 and 356 mV for NiO-500 and NiO-700, respectively. Although NiO-300 displayed the lowest estimated electrochemically active surface area among the samples, it consistently showed the lowest charge-transfer resistance, indicating more favorable interfacial kinetics. Its enhanced performance is therefore associated with the combined effects of defect-related surface species, oxygen-vacancy-related centers, and improved charge-transfer dynamics. Chronopotentiometric measurements at 10 and 100 mA cm–2 further demonstrated the excellent electrochemical stability of NiO-300, while post-OER XRD and Raman analyses confirmed the preservation of its crystalline framework after prolonged operation.
