Search Results (10,461)

Dielectric barrier discharge (DBD) was used as a source of low-temperature plasma generated in a mixture of air and argon at atmospheric pressure for the deposition of a TiO₂ layer from a precursor on a brass or glass substrate. The DBD was generated between two plane-parallel electrodes covered with a dielectric barrier and supplied with an AC high voltage at a frequency of 5 kHz. In this paper, a TiO₂ layer was deposited from vaporised titanium tetraisopropoxide (TTIP), as a precursor, conveyed via argon as a carrier gas in air. The deposited layer was then annealed at a temperature of 450 °C for a time of 2 h. The results of laboratory investigations show that DBD plasma generated in a mixture of air and argon at atmospheric pressure with a precursor can be a useful tool to produce an anatase TiO₂ thin porous layer. The physical properties of the obtained layers were characterised by scanning electron microscopy, energy-dispersive spectroscopy, and Raman spectroscopy. Layer morphology was different depending on the substrate used: in the case of the brass substrate, the layer was built from particles with an average size larger than that of the layer built on the glass substrate. The effect of substrates with different electrical properties on TiO₂ layer morphology deposited in DBD has not yet been investigated. Full article

The present study explores the potential improvement of the mechanical properties of bio-based polyamide 11 (PA11) for demanding industrial application using natural and surface-treated mica at 1, 2 and 5 wt%. Suppressed water uptake by up to 4% was revealed with an unfavorable effect of the surface treatment. Impact strength decreased with filler content from 39.6 kJ m⁻² to between 22–10 kJ m⁻², while stiffness and resistance towards deformation improved: flexural modulus rose from 518.5 MPa to 596 MPa at 5 wt%-treated small particle, and elastic modulus changed from 542.7 MPa to 705.6 MPa. Particle size dependent trends were observed in crystallinity by Differential Scanning Calorimetry (DSC). Surface treatment promoted the presence of a mesophase form, which was also presented by Scanning Electron Microscopy (SEM). Dynamic Mechanical Analysis (DMA) revealed increased internal friction, temperature-dependent modifications in the elastic properties and a glass transition temperature of 36.6 °C. X-ray Diffraction (XRD) proved an unusual decrease in basal spacing of mica from 9.92 to 9.82 Å due to silanization; however, the compounding process provoked some increase again up to 10.03 Å. Results highlight a viable pathway to modify the properties of PA11 with a primarily role in the filler concentration and dimensions over the surface characteristics. Full article

Background: Glioma remains an intractable and highly aggressive brain tumor, mainly due to the daunting obstacle presented by the blood–brain barrier (BBB). To overcome this challenge and enhance therapeutic efficacy, a dual-drug delivery system was engineered. This system co-encapsulated curcumin, a nutraceutical with multitargeted anticancer potential, with atorvastatin calcium, a repurposed anticancer agent, within lipidic nanocapsules (LNCs). Methods: LNCs were prepared via the phase inversion temperature method and optimized using a Box–Behnken design. The optimized LNCs were subsequently functionalized with folic acid (FA) to enable active targeting. FA-LNCs were characterized using XPS, TEM, in vitro release, and MTT cytotoxicity assays. Atorvastatin and curcumin were radiolabeled separately with iodine-131 to evaluate the in vivo pharmacokinetics in a glioma-bearing mouse model. Results: The optimized LNCs and FA-LNCs displayed a mean particle size of 97.98 ± 2.27 nm and 181.60 ± 2.83 nm, a polydispersity index of 0.32 ± 0.07 and 0.40 ± 0.02, and a zeta potential of −15.85 ± 1.35 mV and −11.90 ± 2.80, respectively. XPS and FTIR analyses verified FA conjugation. Both LNCs and FA-LNCs enhanced the in vitro cytotoxicity compared to free drugs; however, the most pronounced effect of FA functionalization was observed in vivo. Most significantly, FA-LNCs achieved markedly greater glioma accumulation than non-functionalized LNCs, with AUC values 2.0-fold higher for atorvastatin and 2.6-fold higher for curcumin. When compared to the free drug solutions, this efficiency was even more pronounced, with atorvastatin and curcumin showing enhancements of 8.2 and 12.4 times, respectively. Conclusions: FA-LNCs markedly improved glioma targeting efficiency and reduced systemic clearance, which underscores the therapeutic potential of integrating nutraceuticals with repurposed agents to achieve effective glioma therapy. Full article

Background: Natural compounds such as fisetin have promising in breast cancer treatment, but their poor pharmacokinetics limit their therapeutic application. This study utilized a synergistic approach by combining fisetin-loaded Nigella sativa (N.S.) oil nanovesicles (FIS-NSs) and carbohydrate-based microneedles (FIS-NSs-MNs) to improve breast cancer management. Methods: Chemical composition of NS petroleum ether extract using gas chromatography–mass spectrometry (GC/MS). FIS-NSs were prepared and characterized for particle size, polydispersity, zeta potential, encapsulation efficiency, and stability. These vesicles were embedded into gelatin, hyaluronic acid, and carboxymethyl cellulose microneedles. In vitro drug release, ex vivo permeation, cytotoxicity against breast cancer cells, and in vivo antitumor efficacy in Ehrlich tumor models were evaluated. Results: Optimized FIS-NSs displayed nanoscale size (190 ± 0.74 nm), low P.D.I (0.25 ± 0.07), high surface charge (+37 ± 0.57 mV), and high encapsulation (88 ± 0.77%). In vitro investigations showed sustained FIS release (~85% over 72 h), while ex vivo permeation showed higher absorption than free fisetin. Both FIS-NSs and FIS-NSs-MNs showed dose-dependent cytotoxicity against breast cancer cells, with lower IC₅₀ than free fisetin (24.7 µM). In vivo, FIS-NSs-MNs and tumor burden inhibition (~77%), reduced oxidative stress (54%), restored antioxidant defenses, and decreased inflammatory markers. Immunohistochemical analysis for caspase-3 showed apoptosis activation within tumor tissues. Conclusions: These findings demonstrate that FIS administration via NS-MNs improves drug stability, penetration, and apoptotic activity, resulting in enhanced anticancer effects. This innovative nanovesicle–microneedle platform provides a non-invasive, effective, and patient-friendly approach for the effective treatment of breast cancer, with potential for broader applications in oncological nanomedicine. Full article

Diffusion bonding (DB) of aluminum alloys faces significant technical challenges, requiring thorough surface preparation and precise control of process parameters. To enhance the joint quality of 7B04 aluminum alloy sheets, pure aluminum (Al) and 7075 aluminum alloy powders were used as interlayers. In the DB experiments, nano-sized Al powder and micro-sized 7075 powders with different particle sizes served as interlayer materials. Compared to DB without an interlayer, using powder interlayers substantially reduced the bonding temperature while improving overall joint performance, with deformation kept below 6%. The lap shear strength (LSS) of the bonded 7B04 joints was significantly higher when 45 μm and 75 μm 7075 powders were used, compared to the 5 μm 7075 powder. The joint with a 50 nm Al powder interlayer achieved a maximum LSS of up to 220 MPa and exhibited considerably higher microhardness. Additionally, the mixed Al/7075 powder interlayer effectively decreased voids at the joint interface, contributing to increased LSS. Full article

The in situ conversion of oil shale with air injection has the advantage of self-generated heat. The fragmentation degree of oil shale affects the oxidative pyrolysis process. In this paper, the basic properties of oil shale were analyzed, and weight loss observation and high-pressure TGA-DSC (thermogravimetric analysis and differential scanning calorimetry) tests in an air atmosphere were conducted using the cores and particles. The oil shale’s oxidative pyrolysis characteristics and the effect of its particle sizes were evaluated. The results show that the porosity and permeability conditions, TOC (total organic carbon), and inorganic mineral composition of oil shale are highly heterogeneous, with higher permeability and greater TOC along the bedding direction. The derivative of the TGA curve shows a single peak, and the heat flow curve shows a double peak that can be used to determine the oil shale’s oxidation type. The oxidative pyrolysis stage of organic matter can be divided into three temperature ranges, of which the medium temperature range is where the most combustion weight loss and heat release occurs. The activation energy of oxidative pyrolysis, which is affected by factors such as particle size, organic matter content, and pyrolysis temperature, is 46.92–248.11 kJ/mol, indicating the varying degrees of difficulty in initiating the reaction under different conditions. The pre-exponential factor is 3.15 × 10²–6.27 × 10¹¹ 1/s, and the enthalpy value is 2.575–4.045 kJ/g. The combustion indexes and reaction enthalpy under different particle sizes are more correlated with their own organic matter content. As oil shale particle size decreases, the variation law of the activation energy and pre-exponential factor changes with temperature from an initial continuous increase to a decrease, then increases again with the smallest kinetic parameters in the medium temperature zone. A small particle size, high organic matter content, and high pressure are more conducive to initiating the oxidative pyrolysis reaction to achieve in situ conversion of organic matter. Full article

Human rhinovirus 16 (HRV-16) is a major cause of common colds and can exacerbate asthma and COPD, yet no approved antiviral treatments exist. Heparin, a highly sulfated polysaccharide, is known to block viral infection of many viruses that require attachment to heparan sulfate proteoglycans (HSPGs). Here, we investigated whether heparin inhibits HRV-16 infection. HRV-16 uses ICAM-1 as its attachment receptor and lacks a confirmed HSPG-binding mechanism. Notably, heparin inhibited HRV-16 infection in vitro in a dose- and time-dependent manner. Pre-treatment of either cells or virus particles with unfractionated heparin significantly reduced HRV-16 RNA expression at 24 and 48 h post-infection. In contrast, low-molecular-weight heparins blocked infection of HRV-16 significantly less effectively compared to unfractionated heparins. Our findings suggest that the inhibitory effect of unfractionated heparin on HRV-16 infection is likely independent of specific HSPGs interactions and may be mediated by the size and highly negative charge of unfractionated heparin. Importantly, the ability of unfractionated heparin to block viruses that do not require HSPGs for attachment implies a broader antiviral potential as a prophylactic or therapeutic agent against a variety of respiratory viruses. Full article

Phosphorus (P) is a critical factor in enhancing agricultural yield improvement, but the over-application of P fertilizers has led to the widespread accumulation of ineffective P in soils worldwide. Artificial humic acid (AHA) has gained recognition as a new method for enhancing P effectiveness in soils. This study aims to explore the patterns and mechanisms underlying the effect of AHA on P effectiveness. A 60-day indoor incubation experiment was conducted using a soil column system, in which the soil was fractionated into five distinct particle size classes: 2 mm, 4 mm, 6 mm, 8 mm, and 10 mm. Findings revealed that AHA effectively promoted the accumulation of Olsen-P in fine-textured soils. Following the application of AHA, the fraction of particles with a size of 2 mm exhibited the highest increase in Olsen-P, at 15.4%, whereas the fraction with a size of 8 mm showed the lowest increase, at 0.2% relative to the control, at the 60th day. Additionally, AHA promoted the migration of HCl-P while enhancing the immobilization of Olsen-P. During the initial cultivation phase, the concentrations of HCl-P in the topsoil (0 cm) differed little from those in the deeper soil (40 cm). As cultivation progressed, the concentrations of NaOH-P and HCl-P in the 0 cm soil decreased more markedly than those at the 40 cm depth by the later cultivation stage. Finally, the structural equation modeling results indicated that among NaHCO₃-P, NaOH-P, and HCl-P, NaOH-P had the most significant effect on Olsen-P. These findings offer valuable insights into how AHA could be used to improve the effectiveness of P in soils. Full article

La³⁺/Bi³⁺ co-doped BaTiO₃ ceramics were synthesized via ball milling followed by heat treatment at 1200 °C according to the Ba_1−3xLa_2xTi_1−3xBi_4xO₃ formula, with dopant levels ranging from x = 0.0 to 0.006. X-ray diffraction and Rietveld refinement confirmed a ferroelectric tetragonal phase for all compositions, with the highest tetragonality (c/a = 1.009) observed for x = 0.001 exceeding that of pure BaTiO₃ (1.0083). High-resolution electron microscopy analysis revealed faceted particles with mean sizes between 362.5 nm and 488.3 nm. Low-doped samples (x = 0.001 and 0.002) exhibited higher permittivity than undoped BaTiO₃, with the maximum dielectric constant (ε_r = 2469.0 at room temperature and 7499.7 at the Curie temperature) recorded for x = 0.001 at 1 kHz. At x = 0.006, minimal permittivity variation indicated a stable dielectric response. A decrease in the Curie temperature was observed with increasing doping levels, indicating a progressive tendency toward the cubic phase. Critical exponent γ values (0.94–1.56) indicated a sharp phase transition for low-doped samples and a diffuse transition for highly doped BaTiO₃. These results showed that La³⁺/Bi³⁺ co-doping effectively tunes the structural and dielectric properties of BaTiO₃ ceramics. Full article

Objective: This study aimed to develop eco-friendly zinc oxide nanoparticles (ZnO NPs) using Punica granatum (pomegranate) peel extract and to evaluate their antioxidant, antimicrobial, and photoprotective potential. Method: ZnO NPs were synthesized via a green chemistry route employing polyphenol- and flavonoid-rich peel extract as reducing and stabilizing agents. The nanoparticles were characterized using FTIR, SEM, XRD, DSC, DLS, and UV–Vis spectroscopy. Biological activities were assessed through in vitro assays including antioxidant (DPPH), anti-collagenase, anti-elastase, anti-tyrosinase, antimicrobial activity, and SPF determination. In vivo photoprotective efficacy was further evaluated in UVB-irradiated rat models, with histological analysis to confirm structural skin changes. Results: The optimized ZnO NPs exhibited an average particle size of ~194 nm with a zeta potential of −18.2 mV, indicating good stability. They demonstrated notable antioxidant activity (DPPH IC₅₀ = 52.91 µg/mL), substantial tyrosinase inhibition (72% at 200 µg/mL), and antibacterial activity with inhibition zones up to 19 mm against S. aureus and 17 mm against E. coli. The nanoparticles also showed excellent UV absorption, with an SPF value of 29.8, exceeding the FDA threshold for effective sun protection. In vivo, topical application of ZnO NPs in UVB-exposed rats led to a 69% reduction in epidermal thickness and preservation of collagen fibers compared with UV controls. Conclusions: These findings confirm that P. granatum peel extract–mediated ZnO NPs possess significant antioxidant, antimicrobial, and photoprotective activities. Full article

The exceptional physicochemical properties of selenium nanoparticles (SeNPs) have led to their widespread development. The function of SeNPs is significantly influenced by their shape and particle size, which are in turn determined by the applied synthesis methods. This work presents a critical and comparative analysis of physical, chemical, and biosynthetic methods. The key point is to elaborate on how different methods precisely regulate the particle size, morphology, and stability that are crucial to their functional efficacy. This work emphasizes the importance of creating standardized protocols for characterizing SeNPs in order to make meaningful comparisons between the effectiveness of various studies. We further elucidate the underlying mechanisms of SeNPs’ anti-tumor, antioxidant, and antibacterial activities. A key novelty of this work lies in its systematic construction of a bridge between the synthesis, properties, functions, applications, and translational potential and its provision of a critical assessment. Finally, the review identifies and summarizes the principal challenges hindering clinical and commercial translation, including the imperative for standardized toxicological evaluation, scalable synthesis, and regulatory alignment. Full article

Nickel–iron (Ni-Fe) catalysts are widely used in industry due to their cost-effectiveness and versatile catalytic properties. This work investigates the structural and morphological characteristics of Ni-Fe catalysts supported on γ-Al₂O₃, synthesized with varying Ni/Fe atomic ratios (from 1:1 to 20:1). The catalysts were characterized using a combination of experimental techniques including X-ray fluorescence (XRF), X-ray diffraction (XRD), scanning and transmission electron microscopy (SEM/TEM), and selected-area electron diffraction (SAED). Theoretical modeling using the USPEX evolutionary algorithm complemented the experimental data by predicting stable Ni-Fe crystal structures. The results revealed uniform metal distribution on the support with particle sizes ranging from 4.1 to 4.5 nm. SAED analysis confirmed the formation of an intermetallic FeNi phase, particularly in samples with higher iron content. This study demonstrates Ni-Fe interaction effects and will be of interest to researchers in catalysis and materials science working on the development of bimetallic systems. Full article

This study aimed to elucidate the effect of pH on the stability of soluble soybean polysaccharide (SSPS)-stabilized dairy beverages. A single-factor experimental design was employed using model systems containing 1.0% (w/v) protein and 0.4% (w/v) SSPS, with pH values adjusted from 3 to 7. System stability was comprehensively evaluated through centrifugation sedimentation rate, particle size distribution, ζ-potential, viscosity, and LUMisizer analysis. As pH increased from 3 to 7, the stability first decreased and then increased, showing the lowest stability at pH 5 and the highest stability at pH 6–7. At pH 5, large SSPS–protein aggregates formed due to the proximity to the isoelectric point (pI) of milk proteins, resulting in increased viscosity (6.83 mPa·s) and reduced ζ-potential (−5.8 mV). Conversely, at pH 6–7, strong electrostatic repulsion and steric stabilization led to small, uniformly dispersed particles and minimal transmittance change (<5%) in LUMisizer analysis. These findings clarify the stabilizing mechanism of SSPS and provide practical guidance for pH regulation in the formulation of dairy beverages. Full article

The sustainable conversion of biogenic waste into high-value materials presents a promising approach for addressing environmental and industrial challenges. This work reports an advancement into antioxidant-enriched phosphate minerals derived from green conversion of biogenic calcium carbonates of crustaceans. We demonstrate the effectiveness of Raman technology in controlling conversion using phosphoric acid treatment. The effects of reaction parameters—including acid stoichiometry, granular size distribution, and thermal treatment at 700 °C and 1200 °C—were systematically evaluated. Raman spectroscopy results validated by X-ray diffraction (XRD) and SEM-EDX analyses revealed mixed-phase minerals monetite, brushite, whitlockite or hydroxylapatite, respectively. Notably, reducing particle size enhanced conversion efficiency by increasing the reactive surface area, while the use of excess phosphoric acid facilitated conversion to monocalcium phosphate and promoted the degradation of the organic matrix. Thermal treatment further altered the product composition: heating at 700 °C produced a whitlockite-rich phase, whereas treatment at 1200 °C shifted the balance toward hydroxylapatite. The synthesized calcium phosphate compounds, including hydroxylapatite, monocalcium phosphate, whitlockite, and brushite, hold significant practical utility in biomedical applications (such as bone grafts and dental implants), agriculture, and industrial processing. Moreover, we have proven that by controlling the reaction parameters the final product composition can be tailored according to the specific needs. A greener approach yields brushite, monetite, or monocalcium phosphate, while a more energy-demanding process, including heating to 1200 °C, yields a high-purity hydroxylapatite. This research offers a sustainable analytical route for producing high-purity calcium phosphate materials from wasted biomaterials, contributing to both the bioeconomy as well as scientific innovation. Full article

Micro(nano)plastics (MNPs), as a globally emerging environmental pollutant, are now ubiquitous in natural environments and can continuously enter the human body through ingestion, inhalation, and dermal contact. This widespread exposure has raised significant concerns regarding the potential health risks posed by MNPs. Although epidemiological studies are still in the early stages, accumulating in vitro cellular experiments have provided key evidence suggesting that nano- to micro-sized plastic particles can cross physiological barriers in the human body. These particles enter cells via endocytosis or direct penetration through the cell membrane, triggering toxic effects such as oxidative stress, immune responses, mitochondrial dysfunction, and DNA damage, which can potentially lead to cell apoptosis. These findings highlight that the direct interaction between MNPs and human cells could be a core mechanism underlying their potential health hazards. This review systematically summarizes the toxic effects of MNPs exposure on various human cell types, exploring the underlying molecular mechanisms and providing insights for future research into the toxicological impacts of MNPs and their implications for human health risk assessment. Full article