Search Results (2,756)

The selective detection of small, highly hydrophilic metabolites differing only in stereochemistry represents a major challenge in biosensor development. Here, we present a computational investigation to elucidate the molecular basis of the experimentally observed selectivity of a protein-based electrochemical biosensor toward myo-inositol over D-chiro-inositol. Although the two stereoisomers differ only in the orientation of a single hydroxyl group, they induce distinct dynamic effects on the protein recognition element. Molecular docking revealed comparable binding regions and similar affinity scores, indicating that selectivity does not arise from differences in binding site or docking energy. To investigate dynamic contributions, all-atom molecular dynamics simulations were performed in triplicate (3 × 100 ns) using the AMBER99SB force field and explicit TIP3P water. Trajectory analyses showed that myo-inositol forms a more persistent hydrogen bond network, resulting in reduced residue-level flexibility, more stable ligand–protein interactions, and enhanced local structural stabilization. Overall, these findings support a dynamic model of stereoselective recognition in which ligand-induced modulation of protein conformational ensembles, rather than static affinity, governs biosensor performance. This work highlights the value of molecular dynamics simulations in the rational design of biosensors targeting structurally similar analytes. Full article

Exhaust piping in diesel engines is subject to severe thermal stress arising from high-temperature, high-pressure gas flows, and spray cooling with atomizing nozzles has become a widely adopted method to safeguard structural reliability. However, at present, the understanding of the spray fragmentation mechanism of two-phase flow under low inlet pressure is still not comprehensive. This study establishes a three-dimensional model of a gas–liquid impinging-jet nozzle and applies a coupled Volume-of-Fluid to Discrete-Phase-Model (VOF–DPM) approach to resolve the liquid breakup process in detail. High-speed imaging experiments were carried out to validate the numerical results. Orthogonal tests were conducted at five pressure levels for both gas and water—0.28, 0.24, 0.20, 0.16, and 0.12 MPa—producing 25 data pairs of spray cone angle and Sauter Mean Diameter (SMD). Within the 0–0.3 MPa air inlet pressure range explored here, raising the pressure consistently reduced the SMD and widened the cone angle, although both trends weakened as the pressure increased. Water inlet pressure exhibited a nonlinear influence, with local extrema appearing in the higher-pressure region. The overall SMD reached a minimum of 34.12 μm and a maximum of 149.04 μm. Using these 25 data points, a genetic algorithm was employed to optimize the pressure ratio under the constraint of total hydraulic power, yielding optimization strategies for different power budgets. An additional outcome of the simulation was the identification of a structural weakness: by reshaping the original flat impingement surface into a full conical surface, atomization quality improved by 29.36% under identical boundary conditions. These findings clarify the atomization mechanism of gas–liquid impinging jets under low inlet pressure and offer practical guidance for nozzle optimization. Full article

Gas-phase thermal deposition was used to form three organosilane self-assembled monolayers on indium tin oxide (ITO) anodes: amine-terminated (NH₂SAM), methyl-terminated (CH₃SAM), and trifluoropropyl-terminated (F₃SAM). Surface characterisation using water contact angle goniometry, ultraviolet photoelectron spectroscopy, and atomic force microscopy was combined with green organic light emitting diode (OLED) fabrication and J–V–L measurements to determine how terminal group chemistry and deposition time affect device performance. F₃SAM increased the ITO work function from 3.72 to 4.47–4.72 eV, resulting in ultrasmooth surfaces (Rₐ = 0.20 nm) and a maximum luminescence of ~6000 cd m⁻², eleven times higher than bare ITO (540 cd m⁻²). CH₃SAM enhanced luminescence through surface passivation at 10 min (3374 cd m⁻²), but decreased quickly with extended deposition durations due to multilayer roughening. NH₂SAM reduced the work function to 3.42 eV and gradually decreased hole injection, resulting in a turn-on voltage of 10–11 V after 180 min. These results indicate that terminal group polarity and deposition duration are the two most important parameters in gas-phase SAM engineering of ITO anodes for OLEDs. Full article

A new method has been established for determining trace amounts of platinum in water using ion liquid (IL)-dispersive liquid–liquid microextraction (DLLME) combined with graphite furnace atomic absorption spectroscopy (GFAAS). The method is based on the use of a self-prepared reagent, 5-(5-cyano-2-pyridineazo)-2,4-diaminotoluene (5-CN-PADAT), as a chelating agent, which reacts with Pt(IV) to form a hydrophobic chelate. The extraction solvent is 1-octyl-3-methylimidazolium hexafluorophosphate ([C₈mim][PF₆]), and ethyl acetate is used as the dispersive solvent. After the extraction is completed, the extraction phase formed by [C₈mim][PF₆] and ethyl acetate has a relatively low viscosity and can be directly used for the determination of GFAAS. A single-factor rotational method was employed to optimize conditions affecting DLLME extraction efficiency. The interactions among the factors affecting DLLME were analyzed using response surface optimization (RSM). Under optimal conditions, platinum concentrations exhibited good linearity within the range of 40–280 ng/mL, with a detection limit of 0.3 ng/mL. AGREEprep was used to discuss the ecological friendliness of the method, demonstrating its low cost, ease of operation, simple equipment requirements, and environmental friendliness. When applied to determining trace amounts of platinum in water samples, the results were satisfactory. Full article

Bacopa monnieri (BM) is a traditional medicinal herb that has been reported to have neuroprotective and cognitive-enhancing properties. In this study, the antioxidant, safety, and neuroprotective properties of BM extract (BME) were assessed in a lipopolysaccharide (LPS) model of cognitive impairment. Ethanol was used for extraction, after which the ethanolic extract was profiled to characterize total phenolic and flavonoid content and major bioactive constituents. The assessment of antioxidant activity was done through several in vitro tests (DPPH, ABTS, FRAP, NBT, OARC, and metal chelation). Toxicity was assessed in Caenorhabditis elegans using pharyngeal pumping and food clearance tests. For in vivo evaluation, rats were pre-treated with BME, and then LPS was administered, followed by evaluation of cognitive performance by the Morris water maze and Y-maze test. Phytochemical examination revealed the existence of phenolics and flavonoids, as well as bacoside A components. The extract showed good antioxidant activity, mainly via hydrogen atom transfer and single-electron transfer, suggesting effective radical scavenging and reducing ability, but no metal chelating activity was observed. Toxicity tests demonstrated that lower concentrations of the extract were well tolerated, and higher concentrations resulted in temporary inhibition of feeding behavior, indicating mild, dose-dependent effects. In the LPS-induced rat model, the inflammatory challenge produced significant cognitive deficits relative to normal controls, validating the model. Pre-treatment with BME at 70 mg/kg did not produce statistically significant rescue of any behavioral endpoint compared with the LPS-only group, although small-to-medium effect sizes in the protective direction were observed for several measures. Additionally, BME modulated LPS-induced neuroinflammatory responses by reducing cortical IL-1β, TNF-α, iNOS, and COX-2 levels while enhancing hippocampal AChE and PGE2 activity, suggesting region-specific anti-inflammatory and cholinergic regulatory effects. The most robust positive findings of this study are therefore the phytochemical characterization and the in vitro antioxidant profile of this standardized extract, which support its potential as a candidate for further investigation in inflammation-related cognitive impairment; the in vivo findings are preliminary and warrant confirmation in larger-scale, dose-ranging studies. Full article

Uranium dioxide (UO₂) is the standard fuel in light water reactors, but improving its mechanical performance is essential for achieving higher burnups. This study employs first-principles density functional theory with the DFT + U approach to investigate the effect of molybdenum (Mo) substitution on the elastic properties of UO₂. Supercell models with Mo concentrations from 3.125 to 9.375 at.% are constructed, and elastic constants are calculated using the stress–strain method, complemented by Bader charge and charge density analyses. The results reveal a non-monotonic concentration-dependent behavior: at 3.125 at.% Mo, the shear and Young’s moduli increase by ~16% and ~14%, respectively, indicating significant stiffening; at higher concentrations (6.25 and 9.375 at.%), both moduli decrease, leading to softening of UO₂ lattice. Bader charge analysis shows that Mo loses only 0.13 electrons (vs. 2.56 for U) and the Mo–O bond is much shorter than the U–O bond; this is evidence of covalent bonding between Mo and O atoms that acts as local strengthening centers at low doping. The softening at higher concentrations is attributed to increased lattice distortion and enhanced bond delocalization, supported by changes in Cauchy pressure, Debye temperature, and Vickers hardness. The calculated elastic modulus and hardness of pure UO₂ are in good agreement with previously reported experimental data. For Mo-doped UO₂ systems, this work establishes a quantitative composition–property relationship, providing a theoretical reference for future experimental investigations. Full article

The search for efficient photocatalysts for sustainable hydrogen production has driven growing interest in barium titanate (BaTiO₃)-based materials, particularly through polymorph control, surface engineering, and nonmetal and transition-metal doping. In this work, we provide an atomic-scale understanding of structural modifications in nitrogen-, fluorine-, and rhodium-doped BaTiO₃ using Density Functional Theory (DFT), as well as pristine and fluorine-substituted BaTiO₃ using reactive force-field molecular dynamics (ReaxFF-MD) simulations. DFT results for pristine and doped tetragonal BaTiO₃, as well as pristine hexagonal BaTiO₃, reveal that nitrogen and rhodium substitutions enhance the covalent character of Ti-N and Rh-O bonds and promote the redistribution of electron density, as evidenced by noncovalent interaction (NCI) and critical point (QTAIM) analyses, whereas fluorine substitution leads to more ionic Ti-F bonding. ReaxFF-MD simulations of pristine and fluorine-substituted BaTiO₃ in contact with water molecules demonstrate that fluorine substitution suppresses interfacial O-H bond formation and promotes ordered molecular hydration layers near titanium sites, as reflected in bond statistics and radial distribution functions. This study provides molecular insights into the role of N, F, and Rh doping in BaTiO₃ using DFT, and the role of fluorine doping in BaTiO₃ at the water–solid interface using ReaxFF-MD simulations, demonstrating that this integrated computational approach provides a solid basis for the rational design of next-generation materials for energy-related applications. Direct calculations of photocatalytic activity, charge transfer rates, and ferroelectric polarization effects were not performed in this work and remain important directions for future study. Full article

Efficient capture of respirable dust remains difficult in fully mechanized excavation roadways because fine particles readily migrate with airflow beyond the effective spray region. Here, a wind-assisted negative-pressure dust suppression device was developed by integrating annular Venturi entrainment with a mechanical air duct, enabling coupled airflow induction and droplet transport. The device was optimized using nozzle atomization tests, CFD-based orthogonal simulations, and laboratory-scale validation. The results show that an SK508 solid-cone nozzle provides suitable atomization for Venturi-induced suction. Using induced air inlet velocity and diffuser-inlet static pressure as evaluation indicators, the optimal Venturi unit was obtained at 0.1 MPa water pressure, 0.4 MPa air pressure, a 15° diffuser angle, and a throat-center nozzle position. For the integrated device, the best configuration was ten Venturi tubes, an impeller rotational speed of 2400 r/min, and an impeller position of 300 mm from the air duct inlet. In laboratory-scale tests, the complete wind-assisted negative-pressure mode outperformed fan-only, spray-only, wind-assisted spray, and negative-pressure secondary dust suppression modes, achieving maximum total and respirable dust suppression efficiencies of 87.39% and 86.68%. The results demonstrate the feasibility of coupling mechanical airflow with Venturi entrainment and support subsequent field-scale validation. Full article

This study presents a green-intensified system for the production of bio-based polyurethane foam using waste cooking oil (WCO) as the primary polyol source. The experimental setup was specifically designed to apply the concept of green intensification by integrating cavitation energy generated through ultrasonic irradiation with a high-shear mixing system. This hybrid approach facilitates the effective mixing of WCO-based bio-polyol with isocyanate, enhancing the reaction during foam formation. An ultrasonic atomizer was employed to convert water into a fine mist, which was then introduced into the reaction mixture using a controlled air blower. The misted water serves as an eco-friendly blowing agent, improving its dispersion within the polyol matrix. The results indicate that this method prolongs gel time, suggesting a more controlled and gradual blowing reaction. Furthermore, the combined use of ultrasonic irradiation and high-shear mixing significantly reduced foam density and produced a finer, more uniform cellular structure. These findings demonstrate that ultrasonic-assisted misting and emulsification not only enhance process efficiency but also contribute to the environmentally sustainable synthesis of bio-polyurethane foam. Full article

As the critical weak link in grouting reinforcement systems, the interfacial adhesion between cementitious grout and rock minerals is highly susceptible to performance degradation under high-temperature and water-rich conditions. In this paper, molecular dynamics simulations were performed across a temperature range of 293 K to 368 K to systematically investigate the effects of high-temperature and water-rich environments on the mechanical response, bonding structure, and dynamic behavior of the grout–rock interface. All simulations were performed using the LAMMPS package with the ClayFF force field. Two interface models, including a CSH/SiO₂ direct-contact model and a CSH/H₂O/SiO₂ water-containing model, were constructed and subjected to uniaxial tensile tests. Key findings are as follows: (i) The tensile strength and interaction energy of the CSH/SiO₂ interface exhibit distinct thermal degradation characteristics. The tensile strength decreases by 32.57%, and the interaction energy by 15.78% when the temperature rises from 293 K to 368 K. High temperatures induce expansion of the interface transition zone from 2.74 Å to 4.60 Å and loosening of the interface structure. (ii) High temperatures intensify atomic diffusion at the interface. The number and stability of Ca-O bonds and hydrogen bonds formed between CSH and SiO₂ are reduced, leading to a decline in interfacial adhesion. (iii) The presence of an interfacial water layer significantly impairs the tensile strength and interaction energy of the interface. Compared with the direct-contact interface, the interaction energy is reduced by 38% at 293 K, and the tensile strength decreases by 73.58%. Water molecules in the solution compete for bonding sites of hydrogen bonds and Ca-O bonds at the interface, weakening the direct interaction between CSH and SiO₂ and transforming it into an indirect interaction mediated by water molecules. Full article

Two-dimensional transition metal carbides and nitrides, known collectively as MXenes, are attractive photocatalyst candidates because their surface chemistry and atomic composition can be tuned over a wide compositional window. A crucial design quantity is the electronic bandgap, which selects whether a given MXene couples with solar radiation and aligns with the redox levels of water splitting. High-fidelity bandgap calculations using the PBE0 hybrid functional are computationally expensive, which has motivated several machine learning surrogates. To the best of our knowledge, this is the first study to integrate a continuous-depth Neural Ordinary Differential Equation backbone with multi-fidelity $\Delta$ learning, distribution-free split-conformal calibration, and uncertainty-aware Pareto screening into a single mathematically grounded pipeline for MXene bandgap prediction. In this work, we develop a physics-constrained neural ordinary differential equation (PC-NODE) that predicts MXene bandgaps from a compact 34-dimensional descriptor set, without relying on the density of states. The model couples a classifier head for the metal/semiconductor decision with a regression head for the gap magnitude, and enforces three physically motivated properties: non-negativity of the predicted gap and monotonicity between the low-fidelity Perdew–Burke–Ernzerhof (PBE) and the high-fidelity PBE0 estimates are obtained exactly through a softplus-parameterised $\Delta$ learning construction, while a hurdle coupling that drives metal predictions towards zero is enforced via a quadratic penalty and verified empirically. In short, two of the three physical constraints are guaranteed by construction, and the third is approximately enforced and verified empirically; the same distinction is maintained consistently in the methodology, the constraint audit and the conclusion. Trained on the 4356-structure MXgap database, a ten-seed ensemble reaches a mean absolute error of $0.186$ eV (per-seed $0.206\pm 0.006$ eV) and a coefficient of determination $R^2=0.880$ on the semiconductor test subset, with a classifier accuracy of $0.856$ and a Receiver Operating Characteristic Area Under the Curve (ROC-AUC) of $0.925$. A split-conformal calibration step then delivers prediction intervals whose empirical coverage matches the 90% target within 0.5 percentage points. Finally, an uncertainty-aware Pareto screening step applies the trained surrogate to a held-out subset of 396 lanthanum-based MXenes and identifies 74 candidates inside the photocatalytic water splitting window [1.23, 3.10] eV. The framework offers a mathematically grounded, data-efficient alternative to feature-heavy pipelines and is reproducible from the open MXgap resource. Full article

This study aims to demonstrate the feasibility of controlling particle size through a mathematical model in the design of industrially applicable ultrasonic spray nozzles by utilizing the vibrational characteristics of piezoelectric ceramics. A piezoelectric ceramic composition with a low sintering temperature and excellent thermal stability (Curie temperature above 300 °C) was developed and used as a ceramic vibrator. Furthermore, the resonance frequency and nozzle displacement were calculated using the COMSOL program and applied to a mathematical model to design an ultrasonic nozzle capable of producing a spray particle diameter of approximately 30 μm. The designed ultrasonic nozzle was fabricated, and its spray characteristics were analyzed. The consistency of the spray characteristics was examined by comparing them with the mathematical model based on changes in ultrasonic nozzle length, resonance frequency, and fluid viscosity. When the ultrasonic nozzle horn length was 22 mm, the resonance frequency was found to be 42.1 kHz, and at a flow rate of 65 mL/min. the average spray particle size was approximately 30–40 μm, indicating fine and uniform particles. In addition, it can be seen that as the length of the nozzle horn increases, the resonance frequency decreases, reducing the supply energy delivered to the liquid, and the particle size increases as shown in the mathematical analysis. The theoretical separation energy required to atomize pure water at a flow rate of 65 mL/min. is 2100 J, which was found to be greater than all energy loss occurring during the atomization process. However, it can be seen that as the length of the ultrasonic nozzle increases, the maximum atomization volume increases, and as viscosity increases, the energy required to separate a single atomized particle becomes greater. Full article

Developing low-cost, non-noble-metal electrocatalysts to replace platinum-based benchmarks for the alkaline hydrogen evolution reaction (HER) remains a critical challenge. Using density functional theory (DFT) calculations combined with the computational hydrogen electrode (CHE) model, we systematically investigate the thermodynamics, kinetics, and intrinsic reaction mechanism of HER on a TiO₂-supported Ni₃ trimer (Ni₃/TiO₂) in alkaline media. We find that the Ni₃ trimer, rather than the TiO₂ support, provides multiple active sites for intermediate adsorption. The trimeric Ni₃ motif generates delocalized electronic states, leading to electron-rich active sites that significantly lower the barrier for water dissociation, facilitate intermediate desorption, and sustain catalytic turnover. The reaction proceeds predominantly via the Volmer–Heyrovsky pathway, where either water dissociation or H₂ desorption can be the rate-determining step, depending on the applied potential. Crucially, the significantly reduced reaction barrier heights demonstrate that the alkaline HER activity of Ni₃/TiO₂ is comparable to that of benchmark Pt₁/TiO₂ single-atom catalysts (SACs). This work establishes a promising design strategy for constructing high-performance non-noble metal few-atom catalysts (FACs) to replace noble metal SACs for multi-step electrocatalytic reactions. Full article

Water pollution caused by antibiotics is a growing problem. Therefore, photodegradation by efficient catalysts is an environmentally friendly technology that can effectively degrade organic pollutants in water. In this work, a method was innovatively used to prepare a ternary heterostructure of plasmon-enhanced Ag-CuO/TiO₂. The composite was synthesized through a facile stepwise strategy involving the formation of CuO nanorods, TiO₂ coating, and subsequent deposition of Ag nanoparticles on their surface using AgNO₃, enabling intimate interfacial contact among the different components. The prepared samples were characterized by XRD, HRTEM, XPS, and UV-Vis. The chemical composition of the composite Ag-CuO/TiO₂ showed a Cu/Ti atomic ratio of 2.58, as well as a Ag/Cu ratio of 0.91. The UV-Vis spectrum reveals the largest absorption peak at 550 nm for the composite Ag-CuO/TiO₂. The prepared Ag-CuO/TiO₂ composites were applied to the visible-light degradation of tetracycline hydrochloride, with the photocatalytic degradation rate reaching 80.7% under the optimal conditions within 60 min, which is significantly better than CuO and CuO/TiO₂ without silver nanoparticles. Capture experiments indicated that h⁺ are involved during the course of the photodegradation and that h⁺ are the main active substances. Furthermore, the proposed mechanism for the photodegradation of the Ag-CuO/TiO₂ composites is given. It has potential applications in the treatment of organic pollutants in water. Full article

This article reviews the state of the art of laser ablation and deposition techniques applied so far to more than 50 elements, including metals, metalloids and lanthanides, yielding a wide variety of compounds in the form of thin films. Laser deposition processes have been performed in high-vacuum (HV) reactors at pressure values ranging between 10⁻¹ and 10⁻⁵ Pa, namely pulsed laser deposition (PLD), or, under different reactive gas ambient (O₂, N₂, CH₄, NH₃ and many others), so-called reactive pulsed laser deposition (RPLD), with the aim to form thin films with desirable chemical compositions. While a few metals have not been deposited as pure metallic films because they have no immediate technological interest, others, like alkali and alkaline earth metals, cannot be deposited in pure metallic form due to their very strong reactivity with oxygen, water vapor and hydrogen molecules which are always present, even in ultra-high-vacuum (UHV) systems, at pressure values of 10⁻⁵–10⁻¹⁰ Pa. Furthermore, elements of the Mendeleev periodic table with an atomic number higher than 88, such as actinides and synthetic elements, are dangerous to handle and deposit in the form of thin films due to their high radioactivity; therefore, they are excluded from this review. The inclusion of the non-metal thin films of carbon (C) and related chemical compounds prepared by PLD and RPLD in the present review is justified by the extensive research and the numerous scientific articles reported in the field. All the results obtained by PLD and RPLD techniques so far are discussed and presented in tabular format to guide the reader. Full article