Search Results (129)

Accurate immobilization is critical in head and neck (H&N) radiotherapy to ensure precise dose delivery while minimizing irradiation of surrounding healthy tissues. However, conventional thermoplastic masks cannot secure 100% replicas of the patient’s surface and are often limited by mechanical weakness, patient discomfort, and workflow inefficiencies. Recently, the best replicas of the patient’s face have been obtained by exploring personal CT or MRI scans of patients that are used for manufacturing of immobilization masks. This study aimed to design and evaluate customizable immobilization masks using acrylonitrile butadiene styrene (ABS)-based composites reinforced with bismuth oxide (Bi₂O₃) and to compare their mechanical performance against commercial thermoplastic masks. ABS and ABS/Bi₂O₃ composite filaments (5, 10, and 20 wt%) were fabricated and characterized by tensile testing. A patient-specific virtual mask was modeled and subjected to finite element analysis (FEA) under clinically relevant loading scenarios, including neck flexion and lateral bending. Results were benchmarked against two commercial thermoplastic masks. ABS and ABS-based composites exhibited significantly higher stiffness (1.7–2.5 GPa) and yield strength (20–25 MPa) compared to commercial thermoplastics (0.25–0.3 GPa, ~7 MPa; p < 0.001). FEA simulations revealed markedly reduced displacement in ABS masks (1–5 mm at 2 mm thickness; <1 mm at 4 mm thickness) relative to commercial masks, which exceeded 20 mm under lateral load. Hybrid configurations with reinforced edges further optimized rigidity while limiting material usage. Customized ABS-based immobilization masks outperform conventional thermoplastics in mechanical stability and displacement control, with the potential to reduce planning margins and improve patient comfort. In addition, ABS-based masks can be recycled, and Bi₂O₃-filled composites can be reused for printing new immobilization masks, thus contributing to a reduced amount of plastic waste. These findings support their promise as next-generation immobilization devices for precision radiotherapy, warranting further clinical validation, workflow integration and sustainable implementation within a circular economy. Full article

In this study, we have investigated heterostructural TiO₂/BiVO₄ anodes to determine the effect of the amount and form of BiVO₄ nanoparticles on TiO₂ on the response of photoanodes under UV and visible illumination. BiVO₄ nanopowders were prepared and annealed at temperatures ranging from 200 to 500 °C. Structural and optical characterization indicates that as the annealing temperature is increased, a phase transition from a weakly ordered to a dominant monoclinic BiVO₄ phase is observed, which is accompanied by an increase in visible light absorption. Subsequently, the most crystalline powder was utilized to deposit BiVO₄ on nanostructured TiO₂ either as a compact overlayer (drop-casting) or as a progressively grown nanoparticle (TiO₂@S series) in the successive ionic layer adsorption and reaction process (SILAR). Photoelectrochemical measurements were performed, revealing a morphology-dependent photocurrent response under UV and visible illumination. A further increase in the number of cycles systematically increases the photocurrent in the visible light range while limiting the response to UV radiation. The TiO₂@d photoanode demonstrates the highest relative activity within the visible range; however, it also generates the lowest absolute photocurrent, indicating the presence of significant transport and recombination losses within the thick BiVO₄ layer. The results demonstrate that the presence of BiVO₄ nanoparticles on TiO₂ exerts a substantial influence on the separation of charge between semiconductors and the synergistic utilization of photons from the UV and visible ranges. This research yielded a proposed scheme of mutual band arrangement and charge carrier transfer mechanism in TiO₂@BiVO₄ heterostructures. Full article

The ubiquitous presence of tetracycline in water sources due to its prevalent usage in antibiotics poses a potential risk to ecosystems and to human health. There is therefore a dire need for efficient methods of tetracycline removal. To this end, we constructed a series of super-small-sized BiVO₄ composites with different loading amounts of 5 wt%, 10 wt%, 15 wt%, 20 wt%, and 25 wt% on SiO₂ support by a hydrothermal–calcination method for efficient photocatalytic degradation of tetracycline. XRD and SEM results revealed that these composites all exhibited good crystallinity and well-dispersed morphologies. Particularly, the 20 wt% BiVO₄@SiO₂ of this series of composites showed superior photocatalytic performance, with 84.1% efficiency in tetracycline degradation, higher than any of its counterparts. This can be explained by its wide light-absorption range and high charge-separation efficiency, as confirmed by UV-Vis absorption spectra and quenched fluorescence spectra. This work offers a new method for the design and construction of tetracycline degradation photocatalysts. Full article

Supramolecular nanoparticles offer an efficient strategy to enhance the solubility, stability, and bioavailability of poorly water-soluble therapeutic molecules. In this study, water-dispersible SNPs were successfully prepared from dicarboxyl-bis-pillar[5]arene (H) and cetyltrimethylammonium bromide (CTAB) using a microemulsion method. Dynamic light scattering revealed that the resulting CTAB/H nanoparticles possessed a size distribution centered around 40 nm, a positive surface charge (+15 mV), and exhibited high colloidal stability over three months. ¹H NMR, 2D TOCSY, 2D NOESY, diffusion ordered NMR spectroscopy, and UV-Vis investigations confirmed the inclusion of the CTAB alkyl chain within the pillar[5]arene cavity, supporting the formation of stable supramolecular assemblies capable of efficiently encapsulating the poorly water-soluble flavonol quercetin (Q). The CTAB/H system displayed low cytotoxicity (up to 50 µg/mL) and pronounced antioxidant activity, as evidenced by DPPH, ABTS, and FRAP assays. Quercetin-loaded nanoparticles (CTAB/H/Q) enhanced cellular uptake and exhibited a marked cytoprotective effect against H₂O₂-induced oxidative stress in NIH-3T3 fibroblasts. Full article

To address the challenge of characterizing bonding strength in hybrid bonding, this paper proposes a method based on post-bonding crack-induced di-cantilever bending (PBC-DCB). The commonly used industrial blade insertion (BI) method only measures the edge strength of wafer-to-wafer samples via bevel geometry, failing to characterize the wafer center or die-to-wafer samples (as they lack a bevel) and exhibiting limited accuracy due to irregular crack edges. This study develops a di-cantilever beam test initiated by a specially prepared post-bonding notch. By deriving the relationship between load–displacement and bonding strength based on fracture mechanics and optimizing sample preparation and testing parameters, quantitative measurement of interface fracture strength is achieved. Experimental results show the method has a deviation < 5% from BI with better repeatability, verifying its reliability. It successfully distinguishes bonding strength between wafer center and edge and reveals that SiCN dielectric layers have 17.34% higher strength and better uniformity than SiO₂. This provides a reliable testing tool for hybrid bonding quality and process optimization, with broad prospects in industrial production and scientific research. Full article

Phosphorus (P) scarcity and pollution demand sustainable recovery strategies. This study engineered a functional straw biochar (F-SBC) from corn straw through synergistic KOH activation and MgCl₂ modification for efficient P recovery and slow release. Characterization revealed that KOH pretreatment expanded pore size and enhanced MgO loading. Batch adsorption experiments demonstrated F-SBC achieved a remarkable P adsorption capacity of 24.70 ± 0.57 mg·g⁻¹, and exhibited > 95% removal efficiency across pH 5~9. Adsorption kinetics followed the pseudo-second-order model, and isotherms fitted the Langmuir model, indicating chemisorption-dominated monolayer adsorption. Mechanistic studies identified synergistic contributions from chemical precipitation, inner-sphere complexation, bi-metallic electrostatic attraction, and physical confinement. F-SBC exhibited slow-release properties, alongside sustained adsorption capacity. Competitive anions (HCO₃⁻/CO₃²⁻) significantly promoted desorption, while Cl⁻ showed minimal impact. This KOH/MgCl₂ co-modification strategy creates a cost-effective, regenerable biochar with superior P recovery and controlled-release potential, advancing sustainable P management from agricultural waste towards a circular bioeconomy. Full article

A novel artificial light-harvesting system (LHS) for the photooxidation reaction was constructed by the phenyl-bis-naphthyl derivative (PBN) and water-soluble phosphate-pillar[5]arene (WPP5). After host–guest interaction, WPP5 integrated with PBN to form WPP5-PBN amphiphiles, which self-assembled to WPP5-PBN nanoparticles. Based on the aggregate state of PBN in WPP5-PBN nanoparticles, WPP5-PBN nanoparticles emitted a significant yellow fluorescence as energy donors. Due to the yellow fluorescence fully covering the absorption of sulforhodamine 101 (SR101), SR101 was used as energy acceptors and loaded in WPP5-PBN nanoparticles for constructing the WPP5-PBN-SR101 LHS, whose energy transfer efficiency and antenna effect were 66.32% and 22.34. Notably, after the energy of the WPP5-PBN antenna transferred to SR101, more singlet oxygen (¹O₂) production was observed in the WPP5-PBN-SR101 LHS, which was successfully used as a photocatalyst to catalyze the oxidation reaction of 4-methoxythioanisole to 1-methoxy-4-(methylsulfinyl)benzene, imitating the solar energy conversion to chemical energy. Full article

A study on the selective solvent extraction (SX) of molybdenum (Mo) and rhenium (Re) from two industrial pregnant leach solutions (PLSs) was carried out using Alamine 336 as the extractant and the ionic liquid (IL) 1-octyl-3-methyl Imidazolium bis (trifluoromethylsulfonyl) imide [Omim][Tf₂N] as the diluent. One industrial PLS was rich in Mo (VI) (PLS-Mo) and the second one rich in Re (VII) (PLS-Re). Experiments were carried out in open vials in which the concentration of Alamine336 in the diluent, the aqueous-to-organic ratio (A/O), and the stripping with ammonium carbonate (${\left(\mathrm{N}{\mathrm{H}}_4\right)}_2\mathrm{C}{\mathrm{O}}_3$) were carried out systematically. Results indicate that decreasing the aqueous-to-organic (A/O) ratio led to an enhancement in the extraction performances of both Mo (VI) and Re (VII), reaching recoveries of 95%–98% at an A/O ratio of 1:1. However, differences between PLSs became evident at higher ratios, as Re extraction declined more sharply than Mo. Third-phase formation was observed only in the Mo-containing PLS. The PLS–Re system did not exhibit the formation of a third phase due to a lower concentration of metal (1 g/L Mo). The use of ammonium carbonate for stripping led to enhanced recoveries, achieving 84.4% for Re and 46.8% for Mo. A total of 50 extraction-stripping cycles were carried out in this work. These demonstrated nearly total initial extraction, but performance decreased over the cycles because of insufficient stripping and solvent loading. Overall, [Omim][Tf₂N] proved to be an effective and environmentally friendly alternative to conventional diluents for Mo and Re separation and recovery from industrial leach solutions. Full article

Polyurea grease (PU) is widely used in the lubrication of heavy machinery, but it can still suffer from structural or performance degradation under extreme conditions such as high temperatures and heavy loads. This study successfully synthesized a hybrid polyurea grease (LiTFSI-PU) by incorporating lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) into polyurea matrix. LiTFSI coordinates with the carbonyl groups (C=O) in the thickener molecules to form weakly Lewis acidic complex, thereby reinforcing the soap fiber network structure. As a result, LiTFSI-PU exhibits increased apparent viscosity under shear. The tribological properties of LiTFSI-PU were evaluated under both ambient and elevated temperature conditions. At a load of 200 N and 150 °C, the average coefficient of friction for the 3 wt% LiTFSI-PU formulation was 0.094, which is 32.3% lower than that of the baseline polyurea grease (PU), while the wear volume was reduced by 77.5%. XPS and FIB-STEM/EDS analyses confirmed that LiTFSI-PU forms a multicomponent protective film in situ during friction, which simultaneously shields the substrate and provides lubrication. The additive strategy proposed in this work offers novel insights for the development of high-performance lubricants suitable for extreme thermomechanical conditions. Full article

Nanothermites are widely applied as specific power sources for microscale initiators and pyrotechnics. Increasing the charge density enhances energy storage within a confined combustion chamber, but it also alters the reaction kinetics. To systemically explore this phenomenon, the combustion and pressurization characteristics of electrosprayed nanothermite-based hybrid energetic materials (THEMs) with different metallic oxides (Fe₂O₃, CuO, and Bi₂O₃) and various energetic additives (nitrocellulose (NC), octogen (HMX), ammonium perchlorate (AP), and hexanitrohexaazaisowurtzitane (CL-20)) across various loading densities were tested. The results showed that increasing the loading density decreased the porosity of the loaded nanothermites and then rapidly decreased the convective heat transfer efficiency during the combustion propagation process. When the loading density exceeded a critical value, a dramatic decrease in the peak pressure, several orders-of-magnitude decrease in the pressurization rate, and an order-of-magnitude increase in the combustion duration occurred. Due to the dual effects of the porous microstructure on heat and mass transfer, the critical density of both the electrosprayed Al/CuO/NC/CL-20 composites and their physically mixed counterparts is between 37.9 and 43.9% theoretical maximum density (TMD). Because of the different synergistic catalytic effects, the fast reactivity at the high-loading-density maintaining capacity of the applied additives was AP > HMX ≈ CL-20 > NC. Owing to their intrinsic properties of low ignition temperature and high gas yield, the Bi₂O₃-THEMs could maintain high-speed reactivity even at 59.7% TMD. These results provide valuable insights into the rational design and tailoring of the reactivity of nanothermites for specific applications. Full article

This research successfully synthesized a novel n-n heterojunction Bi₂O₂CO₃/AgVO₃ nanocomposite photocatalyst via the in situ chemical deposition process. Characterization results strongly confirmed the formation of a tight heterojunction at the Bi₂O₂CO₃/AgVO₃ interface. The nanocomposite exhibited characteristic XRD peaks and FT-IR vibrational modes of both Bi₂O₂CO₃ and AgVO₃ simultaneously. Electron microscopy images revealed AgVO₃ nanorods tightly and uniformly loaded onto the surface of Bi₂O₂CO₃ nanosheets. Compared to the single-component Bi₂O₂CO₃, the composite photocatalyst exhibited a red shift in its optical absorption edge to the visible region (515 nm) and a decrease in bandgap energy to 2.382 eV. Photoluminescence (PL) spectra demonstrated the lowest fluorescence intensity for the nanocomposite, indicating that the recombination of photogenerated electron–hole pairs was suppressed. After 90 min of visible-light irradiation, the degradation efficiency of Bi₂O₂CO₃/AgVO₃ toward methylene blue (MB) reached up to 99.55%, with photodegradation rates 2.51 and 2.79 times higher than those of Bi₂O₂CO₃ and AgVO₃, respectively. Furthermore, the nanocomposite exhibited excellent cycling stability and reusability. MB degradation was gradually enhanced with increasing the photocatalyst dosage and decreasing initial MB concentration. Radical trapping experiments and absorption spectroscopy of the MB solution revealed that reactive species h⁺ and ·O₂⁻ could destroy and decompose the chromophore groups of MB molecules effectively. The possible mechanism for enhancing photocatalytic performance was suggested, elucidating the crucial roles of charge carrier transfer and active species generation. Full article

Bi₂Sr₂CaCu₂O_8+x (Bi2212) high-temperature superconductor exhibits broad application prospects in strong magnetic fields, superconducting magnets, and power transmission due to its exceptional electrical properties. However, during practical applications, Bi2212 superconducting round wires are prone to mechanical loading effects, leading to crack propagation and degradation of superconducting performance, which severely compromises their reliability and service life. To elucidate the damage mechanisms under mechanical loading and their impact on critical current, this study establishes a two-dimensional model with existing cracks based on phase field fracture theory, simulating crack propagation behaviors under varying conditions. The results demonstrate that crack nucleation and propagation paths are predominantly governed by stress concentration zones. The transition zone width of cracks is controlled by the phase field length scale parameter. By incorporating electric fields into the phase field model, coupled mechanical-electrical simulations reveal that post-crack penetration causes significant current shunting, resulting in a marked decline in current density. The research quantitatively explains the mechanism of critical current degradation in Bi2212 round wires under tensile strain from a mechanical perspective. Full article

This research introduces a synergistic photoelectrocatalytic (PEC) system designed for the effective degradation of tetracycline (TC), integrating a PO₄³⁻-grafted Mo-doped BiVO₄ (PO₄³⁻-Mo:BiVO₄) photoanode with a Pd-loaded ordered mesoporous carbon (Pd/CMK-3) cathode. The incorporation of Mo doping and PO₄³⁻ modification significantly improved the photoanode’s charge separation efficiency, achieving a photocurrent density of 2.9 mA cm⁻², and fine-tuned its band structure to enhance hydroxyl radical (·OH) generation. Meanwhile, the Pd/CMK-3 cathode promoted a two-electron oxygen reduction reaction pathway, producing hydrogen peroxide (H₂O₂) and facilitating molecular oxygen activation via atomic hydrogen (H*) intermediates. Under optimized conditions—1.0 V vs. Ag/AgCl of anodic potential, pH 6.58, and oxygen saturation—the combined system accomplished 80% TC degradation within 60 min, markedly surpassing the performance of the photoanode (72%) or cathode (71%) alone. Notably, this synergistic approach also reduced energy consumption to 0.0065 kWh m⁻³, outperforming individual components. Radical quenching experiments and liquid chromatography–mass spectrometry (LC-MS) analysis revealed that the photogenerated holes (h⁺) and ·OH were the key reactive species responsible for TC mineralization. The system demonstrated remarkable stability, with only a 2.96% decline in activity, and effectively degraded other contaminants, such as phenol, 4-chlorophenol, and ciprofloxacin. This study highlights an energy-efficient PEC strategy that harnesses the combined strengths of anodic oxidation and cathodic molecular oxygen activation to significantly enhance the removal of organic pollutants. Full article

Catalytic upgrading of pyrolysis oils is an important step for producing replacement hydrocarbon-rich liquid biofuels from biomass and can help to advance pyrolysis technology. Catalysts play a pivotal role in influencing the selectivity of chemical reactions leading to the formation of main compounds in the final upgraded liquid products. The present work involved a systematic study of solvent-free catalytic reactions of cyclohexanone in the presence of hydrogen gas at 160 °C for 3 h in a batch reactor. Cyclohexanone can be produced from biomass through the selective hydrogenation of lignin-derived phenolics. Three types of catalysts comprising undoped NbOPO₄, 10 wt% NiO/NbOPO₄, and 30 wt% NiO/NbOPO₄ were studied. Undoped NbOPO₄ promoted both aldol condensation and the dehydration of cyclohexanol, producing fused ring aromatic hydrocarbons and hard char. With 30 wt% NiO/NbOPO₄, extensive competitive hydrogenation of cyclohexanone to cyclohexanol was observed, along with the formation of C₆ cyclic hydrocarbons. When compared to NbOPO₄ and 30 wt% NiO/NbOPO₄, the use of 10 wt% NiO/NbOPO₄ produced superior selectivity towards bi-cycloalkanones (i.e., C₁₂) at cyclohexanone conversion of 66.8 ± 1.82%. Overall, the 10 wt% NiO/NbOPO₄ catalyst exhibited the best performance towards the production of precursor compounds that can be further hydrodeoxygenated into energy-dense aviation fuel hydrocarbons. Hence, the presence and loading of NiO was able to tune the activity and selectivity of NbOPO₄, thereby influencing the final products obtained from the same cyclohexanone feedstock. This study underscores the potential of lignin-derived pyrolysis oils as important renewable feedstocks for producing replacement hydrocarbon solvents or feedstocks and high-density sustainable liquid hydrocarbon fuels via sequential and selective catalytic upgrading. Full article

The use of semiconductors for photocatalytic degradation of organic pollutants has garnered considerable attention as a promising solution to environmental challenges. Compared to TiO₂, BiPO₄ exhibits superior photocatalytic activity. However, its large band gap restricts its light absorption to the UV region. One effective technique for extending BiPO₄’s absorption wavelength into the visible spectrum is the construction of the heterostructure. This study aimed to synthesize monodisperse BiPO₄ nanorods via a solvothermal approach and fabricate BiPO₄/g-C₃N₄ heterojunctions with varying loadings through in situ deposition. Tetracyclines were employed as the target pollutant to evaluate the photocatalytic performance and stability of the prepared materials. The results indicated that 5 wt% of composite exhibited better photocatalytic performance than single catalysts, which showed the highest photodegradation efficiency of approximately 98% for tetracyclines. The prepared bi-photocatalyst presented favorable stability under sunlight irradiation, the photocatalytic activity of which remained almost unchanged after four cycles. The enhanced photocatalytic activity was attributed to the synergistic effect. Additionally, the possible degradation mechanism was elucidated utilizing the semiconductor energy band theory. Overall, this work presents new perspectives on synthesizing innovative and efficient visible-light-driven photocatalysts. It also offers a mechanistic analysis approach by integrating theoretical calculations with experimental observations. Full article