Search Results (487)

Utilizing waste tire crumb rubber (CR) in asphalt modification is a promising method to enhance pavement performance while addressing the issue of waste tire disposal. Elevating CR content without compromising the pavement performance of asphalt is crucial for its practical and sustainable applications. However, conventional crumb-rubber-modified asphalt (CRMA) exhibits weakened physical and pavement properties when the CR content exceeds 25 wt%. Here, we propose a hybridization strategy combining CR and devulcanized CR (DCR) to produce high-performance modified asphalt with a total rubber content of up to 43wt%. Modified asphalt containing 30wt% CR and 13 wt% DCR (30CR-13DCRMA) demonstrates remarkable physical properties, with a softening point of 78.4 °C and a ductility of 15.33 cm. Rheology tests further reveal its superior rutting resistance (G*/sin δ), fatigue tolerance (G*·sin δ), and overall pavement performance compared to neat CR- or DCR-modified asphalt. Through rheological analysis, sol fraction measurement, gel permeation chromatography (GPC), and atomic force microscope (AFM) tests, it is revealed that the synergistic effect of CR and DCR can enhance the absorption capabilities of rubber particles, promoting their full swelling and resulting in a biphasic hard/soft microstructure within the asphalt matrix. This structural reorganization contributes to the outstanding comprehensive properties of this modified asphalt. This work establishes a hybrid-rubber asphalt system with high CR incorporation and well-balanced performance, offering a viable pathway toward sustainable pavement engineering. Full article

Epicatechin is a flavonoid of the catechin subclass, found in fruits and medicinal plants such as açaí and green tea, widely studied for its anti-inflammatory properties. However, flavonoids often present chemical instability, low aqueous solubility, and poor bioavailability, limiting their therapeutic potential. This study aimed to incorporate epicatechin into nanocapsules to improve its applicability and evaluate whether the formulation maintains its anti-inflammatory effects via modulation of the NLRP3 inflammasome. Nanocapsules containing 0.25 mg/mL of epicatechin (NC-ECs) were prepared with Eudragit L-100 using interfacial deposition of a preformed polymer. The formulations were characterized for particle size, polydispersity index, zeta potential, and pH, as well as thermal stability over 45 days. Encapsulation efficiency and drug content were determined by high-performance liquid chromatography (HPLC), and morphology analyzed by atomic force microscopy (AFM). Cytocompatibility was assessed in VERO cells, and anti-inflammatory activity was investigated in THP-1-derived macrophages stimulated with LPS + nigericin. The NC-ECs displayed suitable physicochemical properties, high encapsulation efficiency (96%), and full drug loading. The formulation also showed good cytocompatibility and preserved anti-inflammatory activity through NLRP3 inflammasome modulation at low concentrations. These findings indicate NC-ECs as a promising nanotechnological strategy for treating inflammatory diseases involving NLRP3, highlighting its potential contribution to nanomedicine. Full article

Diamond, as an exceptional material with many superior properties, requires a single crystal in a reasonably large size for practical industrial applications. However, achieving large-area single-crystal diamond (SCD) growth without the formation of polycrystalline rims remains challenging. Microwave plasma chemical vapor deposition (MPCVD) using a gas mixture of 10% CH₄-H₂ was used for the homoepitaxial growth of (001) SCD. The effect of nitrogen gas addition in the range of 0–2000 ppm on lateral growth was investigated. Deposition with 180 ppm N₂ over a growth duration of 20 h to reach a thickness of 0.95 mm resulted in significantly enhanced lateral growth without the appearance of a polycrystalline diamond (PCD) rim for the grown diamond, and the total top surface area of SCD increased by an area gain of 1.6 relative to the substrate. The corresponding vertical and lateral growth rates were 47.3 µm/h and 52.5 µm/h, respectively. Characterization by Raman spectroscopy and atomic force microscopy (AFM) revealed uniform structural integrity across the whole surface from the laterally grown regions to the center, including the entire expanded area, in terms of surface morphology and crystalline quality. Moreover, measurements of the etch pit densities (EPDs) showed a substantial reduction in the laterally grown regions, approximately an order of magnitude lower than those in the central region. The high quality of the homoepitaxial diamond layer was further verified with (004) X-ray rocking curve analysis, showing a narrow full width at half maximum (FWHM) of 11 arcsec. Full article

Single-atom catalysts (SACs) have attracted extensive attention owing to their outstanding catalytic performance and nearly complete atom utilization efficiency. However, the environmental sustainability of SACs across their full life cycle has not yet been systematically investigated. This review emphasizes the necessity of integrating life cycle assessment (LCA) into SACs to support their sustainable development. By analyzing the structural characteristics, synthesis strategies, and representative application fields, this study examines how LCA principles can be employed to reveal the hidden environmental burdens associated with raw material extraction, synthesis processes, usage stages, and end-of-life management. Based on existing LCA case studies of catalytic materials, this review identifies the key challenges in the SACs field and proposes a preliminary framework for sustainable SAC design with LCA as a guiding approach. Finally, the review summarizes the current challenges and future perspectives, emphasizing that developing more specific evaluation standards, improving database construction, and adopting dynamic assessment methods are essential to shift LCA from a passive evaluation tool to an active design strategy that drives the green development of next-generation SACs. Full article

We investigate the spatial structure of quantum entanglement in one- and two-dimensional lattice systems containing structural defects, using the Time-Dependent Quantum Monte Carlo (TDQMC) method. By constructing reduced density matrices from ensembles of guide waves, we resolve spatial variations in both Coulomb-mediated entanglement and coherence without requiring full many-body wavefunctions. This approach reveals localized regions, entanglement islands, where quantum correlations are enhanced or suppressed due to the presence of vacancies or interaction inhomogeneities. In 1D systems, entanglement tends to concentrate near defects, while in 2D systems, we observe bridge-like and radially symmetric domains. Our results demonstrate that TDQMC offers a scalable and physically transparent framework for real-space quantum information analysis, with implications for information transfer in atomic-size structures, quantum materials, entanglement-based sensing, and coherent state engineering. Full article

The emergence of metalenses has opened new possibilities for miniaturizing optical systems. However, the limited group delay provided by meta-atoms restricts their aperture size under broadband operation. This challenge has stimulated the development of hybrid refractive–metalens systems, which overcome the performance limitations of individual metalenses while achieving a more compact form factor than conventional refractive lens assemblies. Here, we propose a design methodology for hybrid lenses that combines ray tracing with full-wave simulation. We analyze key aspects of the metalens within the hybrid system for a wide wavelength band—specifically, dispersion and transmission efficiency. Based on this approach, we designed a high-resolution hybrid lens operating in the 435–656 nm visible band with a 35° field of view. The results demonstrate that the proposed lens achieves imaging performance equivalent to that of conventional refractive systems while reducing the total track length by 29%. This validates the effectiveness of our design method, indicating its strong potential for application in compact and lightweight optical systems. Full article

We do not know a priori chemical composition of a star. However, with more high resolution spectra becoming more abundant thanks to the development of space-born observations, atomic data including Stark broadening parameters for various spectral lines for elements in various ionisation stages are becoming more feasible. Particularly are important spectral lines of C-N-O peak in the distribution of abundances of chemical elements. For the calculation of Stark broadening parameters, spectral line full widths at half intensity maximum (FWHM) and shifts, we used semiclassical perturbation method. As the result, Stark widths and shifts for 36 spectral lines of neutral oxygen, broadened by the collisions with electrons, protons and helium ions, have been obtained and compared with other theoretical calculations. These data are of interest for a number of problems in astrophysics, plasma physics, as well as for inertial fusion and various plasmas in technology. Full article

Quantum spin transport in integrable systems reveals a rich nonequilibrium phenomena that challenges the conventional hydrodynamic framework. Recent advances in ultracold atom experiments with state preparation and single-site addressing have enabled the understanding of this anomalous behavior. Particularly, the full universality characterization of exotic initial states, as well as their measurement representation, remain unknown. By employing tensor network and contrast methods, we systematically investigate spin transport in the quantum XXZ spin chain and extract dynamical scaling exponents emerging from two paradigmatic and experimentally attainable initial states, i.e., multi-periodic domain-wall (MPDW) and spin-helix (SH) states. Our results using different values of anisotropic parameters $\Delta \in [0,1.2]$ demonstrate the evident impeded transport and the difference between the two states with increasing $\Delta$ values. Large-scale and consistent simulations confirm the contrast method as a viable scaling extraction approach for exotic states with periodicity within experimentally accessible timescales. Our work establishes a foundation for studying initial memory and the corresponding relations of emergent transport behavior in nonequilibrium quantum systems, opening avenues for the identification of their unique universality classes. Full article

Bilayer transition metal dichalcogenides (TMDs) are promising materials for next-generation field-effect transistors (FETs) due to their atomically thin structure and favorable transport properties. In this study, we employ density functional theory (DFT) to compute the electronic band structures and phonon dispersions of bilayer WS₂, WSe₂, and MoS₂, and the electron-phonon scattering rates using the EPW (electron-phonon Wannier) method. Carrier transport is then investigated within a semiclassical full-band Monte Carlo framework, explicitly including intrinsic electron-phonon scattering, dielectric screening, scattering with hybrid plasmon–phonon interface excitations (IPPs), and scattering with ionized impurities. Freestanding bilayers exhibit the highest mobilities, with hole mobilities reaching 2300 cm²/V·s in WS₂ and 1300 cm²/V·s in WSe₂. Using hBN as the top gate dielectric preserves or slightly enhances mobility, whereas HfO₂ significantly reduces transport due to stronger IPP and remote phonon scattering. Device-level simulations of double-gate FETs indicate that series resistance strongly limits performance, with optimized WSe₂ pFETs achieving ON currents of 820 A/m, and a 10% enhancement when hBN replaces HfO₂. These results show the direct impact of first-principles electronic structure and scattering physics on device-level transport, underscoring the importance of material properties and the dielectric environment in bilayer TMDs. Full article

In this paper, a broadband photoconductive antenna (PCA) with enhanced full-band radiation power is proposed based on dual-frequency complementary technology. In the proposed PCA, dual-frequency metallic bar resonators are combined with the coplanar transmission line. Dual-frequency resonant cascades in the meta-atomic electrodes enable effective manipulation of the dissipated terahertz energy along the coplanar lines of PCAs and efficient scattering of terahertz energy into the far field, thereby enhancing far-field radiation power. To validate the proposed antenna, the prototype of the proposed PCA is manufactured and measured. Compared with the conventional PCA, experimental results indicate that our PCA increases the THz radiation power of the entire radiation frequency band (0.02–1.5 THz) by 4.5 times. In addition, our experiments demonstrate that the proposed PCA overcomes the narrowband resonant response characteristics of traditional methods, significantly improving energy utilization efficiency. This design offers a reproducible and universal approach to effectively harness this dissipated terahertz energy, opening a path to rapidly advancing the practicality of terahertz techniques. Full article

The urgent need to reduce greenhouse gas emissions and shift towards renewable energy has increased attention on biochar as a viable negative emission strategy. This review assesses the potential of biochar produced from organic and waste biomass via thermochemical processes—including pyrolysis, gasification, and hydrothermal carbonization—to address climate and energy challenges. Recent advances in biochar production are critically examined, highlighting how process design controls improve key properties such as carbon stability, atomic ratios, porosity, and energy density. These factors influence biochar’s performance in carbon sequestration and its utility across industrial sectors, ranging from agriculture and construction to energy generation and carbon capture systems. Results indicate that large-scale adoption of biochar could lower carbon emissions, enhance soil fertility, and produce renewable fuels like hydrogen, while also benefiting circular economy initiatives. However, obstacles remain, including economic costs, feedstock logistics, process optimization, and potential environmental or social impacts. This review underscores that unlocking biochar’s full promise will require interdisciplinary research, robust quality standards, and supportive policies. With integrated efforts across science, industry, and policy, biochar can serve as an effective and sustainable technology for emission reduction and contribute significantly to global carbon neutrality goals. Full article

A fully connected neural network was trained to model the K-shell ionization cross sections based on two input features: the atomic number and the incoming electron overvoltage. The training utilized a recent, updated compilation of experimental data covering elements from H to U, and incident electron energies ranging from the threshold to relativistic values. The neural network demonstrated excellent predictive performance, compared with the experimental data, when available, and with full theoretical predictions. The developed model is provided in the ikebana code, which is openly available and requires only the user-selected atomic number and electron energy range as inputs. Full article

The move toward environmentally friendly methods in the global manufacturing sector has led to the use of minimum quantity lubrication (MQL) as an eco-friendly alternative to traditional flood cooling. However, the natural limits of MQL in high-performance settings have led to the use of nanotechnology, which has resulted in the creation of nanofluids, engineered colloidal suspensions that significantly improve the thermophysical and tribological properties of base fluids. This paper gives a complete overview of the latest developments in nanofluid technology for use in machining. It starts with the basics of MQL and the rules for making, describing, and keeping nanofluids stable. The review examines the application and effectiveness of single and hybrid nanofluids in various machining processes. It goes into detail about how they improve tool life, surface integrity, and overall efficiency. It also examines the benefits of integrating nanofluid-assisted MQL (NMQL) with more advanced and hybrid systems, including cryogenic cooling (cryo-NMQL), ultrasonic atomization, electrostatic–magnetic assistance, and multi-nozzle delivery systems. The paper also gives a critical look at the main problems that these technologies face, such as the long-term stability of nanoparticle suspensions, their environmental and economic viability as measured by life cycle assessment (LCA), and the important issues of safety, toxicology, and disposal. This review gives a full picture of the current state and future potential of nanofluid-assisted sustainable manufacturing by pointing out important research gaps, like the need for real-time LCA data, cost-effective scalability, and the use of artificial intelligence (AI) to improve processes, and by outlining future research directions. Full article

The contamination of food and beverages with heavy metals, such as Cd, presents significant health risks, underscoring the need for reliable and sensitive analytical methods. This study introduces the development of a rapid, cost-effective, and environmentally friendly method for Cd determination in cachaça, a traditional Brazilian sugarcane spirit. Magnetic nanoparticles (Fe₃O₄) functionalized with tetraethyl orthosilicate are synthesized and employed as adsorbents in a dispersive magnetic solid-phase extraction procedure. The extracted Cd is quantified using flame atomic absorption spectrometry. A full factorial experimental design is used to optimize key parameters, including the sorbent mass, adsorption time, desorption time, and acid concentration. The method demonstrates excellent analytical performance, with a linear calibration range (R² = 0.99), detection limit of 0.0046 mg L⁻¹, and quantification limit of 0.0200 mg L⁻¹. Moreover, validation results show high precision (coefficient of variation < 9.10%) and accuracy (recovery rates between 92.00% and 120.00%). When analyzing commercial cachaça samples, cadmium was detected in all five specimens. Notably, in one sample the cadmium concentration exceeded Brazil’s maximum permissible limit of 0.0200 mg kg⁻¹, underscoring the importance of this work for ensuring food safety. The proposed method offers a sensitive, reproducible, and sustainable approach for analysis of potentially toxic trace metals in alcoholic beverages, reinforcing its potential for routine monitoring and regulatory compliance. Full article

To study the adsorption of lanthanide (Ln) atoms on graphene containing a Stone–Wales defect, we used a cluster model (SWG) and performed calculations at the PBE-D2/DNP level of the density functional theory. Our previous study, where the above combination was complemented with the ECP pseudopotentials, was only partially successful due to the impossibility of calculating terbium-containing systems and a serious error found for the SWG complex with dysprosium. In the present study we employed the DSPP pseudopotentials and completely eliminated the latter two failures. We analyzed the optimized geometries of the full series of fifteen SWG + Ln complexes, along with their formation energies and electronic parameters, such as frontier orbital energies, atomic charges, and spins. In many regards, the two series of calculations show qualitatively similar features, such as roughly M-shaped curves of the adsorption energies and trends in the changes in charge and spin of the adsorbed Ln atoms, as well as the spin density plots. However, the quantitative results can differ significantly. For most characteristics we found no evident correlation with the lanthanide contraction. The only dataset where this phenomenon apparently manifests itself (albeit to a limited and irregular degree) is the changes in the closest Ln^…C approaches. Full article