Search Results (49)

The photocatalytic efficiency of graphitic carbon nitride (g-C₃N₄) for the decomposition of aqueous rhodamine B (RhB) was investigated. To examine the combined effects of sonication and electron beam (EB) irradiation on the photocatalytic efficiency, g-C₃N₄ was sonicated in 1,3-butanediol and subsequently irradiated with EB. The photocatalytic efficiency was improved by the low-dose EB irradiation due to the generation of structural defects that acted as active reaction sites. Sonication before EB irradiation induced mild exfoliation and further improved photocatalytic efficiency. Prolonged sonication enhanced this improvement, primarily by increasing the specific surface area of g-C₃N₄. The positive effect of sonication was more remarkable for g-C₃N₄ irradiated with low-dose EB than for g-C₃N₄ irradiated with higher-dose EB. The photocatalytic RhB decomposition rate measured for g-C₃N₄ sonicated for 480 min and irradiated at 200 kGy was approximately 6.8 times higher than that measured for the untreated g-C₃N₄. The difference between the sonication effects can be ascribed to the electrostatic interactions and the resultant agglomeration of the g-C₃N₄ particles after EB irradiation. High-dose EB irradiation caused electrification followed by coarsening of the particles, whereas low-dose EB irradiation did not produce these results and led to positive effects due to the EB-induced g-C₃N₄ structural alteration. Full article

Enhancing the surface mechanical properties and extending the service life of 45CrNiMoV mold steel are critical goals in mold development. To achieve these objectives, electron beam (EB) irradiation was employed to treat the 45CrNiMoV mold steel. This high-energy physical process enables precise modification of the surface microstructure. By meticulously controlling EB parameters, including energy, dose, and scanning mode, significant structural alterations occur in the surface layer. Consequently, the surface microhardness more than doubles, reaching 812.7 HV. This enhancement is attributed to grain refinement, increased dislocation density, and potential formation of new phases induced by EB irradiation. Beyond hardness improvement, the wear resistance of the treated specimen increases by 2.5-fold. Under standardized testing conditions, wear loss decreases markedly from 0.28 mg to 0.11 mg. This reduction in wear loss not only extends the mold’s operational lifespan but also minimizes maintenance and replacement requirements, thereby reducing production downtime and associated costs. This study transcends mere presentation of experimental data by comprehensively elucidating the intricate relationship between surface microstructure and the overall mechanical properties of 45CrNiMoV mold steel. Advanced characterization techniques, including scanning electron microscopy (SEM) and X-ray diffraction (XRD), were utilized to uncover the underlying mechanisms. The refined microstructure, characterized by fine grains and elevated dislocation density, impedes dislocation movement and crack propagation, thereby enhancing both hardness and wear resistance. Full article

The photocatalytic activity of silica–titania (S-T) fibers synthesized via sol–gel and electrospinning was evaluated using methyl orange (MO), eriochrome black T (EB), and methylene blue (MB) as model dyes. Characterization by X-ray diffraction confirmed the presence of anatase and rutile TiO₂ phases, while UV-Vis spectroscopy determined a bandgap energy of 3.2 eV. Scanning electron microscopy revealed fibers with an average diameter of 214 nm. Under UV irradiation, nearly complete dye removal (initial concentration: 30 mg/L; catalyst dosage: 0.1 g/L) was achieved within 8 h. The reaction kinetics followed the Langmuir–Hinshelwood model, with significant differences in apparent reaction rates (k_a) among the dyes, attributable to their distinct structural and functional properties. This study establishes silica–titania fibers as a high-performance, highly versatile composite photocatalyst. Achieving 98% degradation efficiency, their key innovation is their fibrous morphology, which solves the critical problem of powder catalyst recovery. This enables a paradigm shift from simple lab efficiency to practical, sustainable application. Full article

High-density polyethylene (HDPE) is a valuable material, but its application under certain operational conditions is limited by oxidation resistance. To mitigate this, rice husk ash (RHA), a silica-rich (~95%) byproduct, was incorporated as a reinforcing filler. This study evaluates the effect of electron beam (EB) irradiation, at doses up to 100 kGy, on the properties of HDPE/RHA composites, focusing on mechanical performance and the polymer–filler interface. The results demonstrate that EB irradiation induces crosslinking and enhances interfacial interaction between the HDPE matrix and RHA filler. While the overall tensile strength of neat HDPE tended to decrease with irradiation dose (from 28.5 ± 1.2 MPa to 24.1 ± 1.5 MPa at 100 kGy), the optimization of dose and filler contents produced notable results: A maximum tensile strength of 29.0 ± 1.1 MPa was achieved in the composite containing 5 wt% RHA at 75 kGy. Furthermore, irradiation stabilized the material’s behavior, resolving the heterogeneous dispersion observed in non-irradiated samples with low RHA content. Regarding toughness, Izod’s impact resistance increased from 3.2 ± 0.2 kJ/m² to 3.7 ± 0.3 kJ/m² for the 10 wt% RHA composites irradiated at 50 kGy. Statistical analysis (ANOVA, p < 0.05) confirmed the significance of these changes. In conclusion, electron beam irradiation is an effective tool for optimizing the mechanical properties and performance uniformity of HDPE/RHA composites, making them promising candidates for applications requiring enhanced durability and consistency, such as food packaging. Full article

This study compared the effects of storage time and electron beam (EB) irradiation on microbial counts and chemical stability of dried flowers from two hemp cultivars over 12 weeks. Cannabinoid and terpene content, as well as microbial load, were evaluated at 0, 4, 8, and 12 weeks in EB-irradiated and non-irradiated samples. Microbial count in non-irradiated flowers reached up to 4.1 × 10⁶ colony-forming units (CFU)/g; EB irradiation reduced these levels to <10² CFU/g. Cannabinoid contents were unaffected by EB irradiation and remained stable throughout storage. Terpene content decreased by 8.4% immediately after irradiation, followed by further declines during storage, reaching 22.3% and 24.0% average losses in non-irradiated and EB-irradiated samples after 12 weeks, respectively. EB irradiation caused a higher decrease in monoterpenes (10.8%) than in sesquiterpenes (2.5%). These findings confirm that EB irradiation is an effective sterilization method for hemp flowers that preserves chemical integrity. Storage time also significantly reduced microbial loads in non-irradiated samples; TAMC in cultivar B declined from 20,728 CFU/g to <LOQ (100 CFU/g), and TYMC decreased 16-fold. Cultivar A exhibited a sharp initial TAMC reduction followed by fluctuations and TYMC levels that were 7-fold lower by Week 12, reflecting natural microbial decay during hemp flower storage. Full article

Hydrogels exhibit remarkable physicochemical properties, including high water absorption and retention capacities, as well as controlled release behavior. Their inherent biodegradability, biocompatibility, and non-toxicity make them suitable for a wide range of applications. Cellulose, a biodegradable, renewable, and abundantly available polysaccharide, is a viable source for hydrogel preparation. Ionizing radiation, using electron-beam (EB) or gamma (γ) irradiation, provides a promising approach for synthesizing hydrogels. This study reviews recent advancements in cellulose-based hydrogels, focusing on cellulose and its derivatives, brief information regarding ionizing radiation, comparison between EB and γ-irradiation, synthesis and modification through ionizing radiation technology, and their environmental and agricultural applications. For environmental remediation, these hydrogels have demonstrated significant potential in water purification, particularly in the removal of heavy metals, dyes, and organic contaminants. In agricultural applications, cellulose-based hydrogels function as soil conditioners by enhancing water retention and serving as carriers for agrochemicals. Full article

This study investigates the combined use of electron beam irradiation (EBI) and nanotechnology to develop improved food packaging films. EBI, commonly applied for sterilization, can alter polymer microstructure, while irradiated cellulose nanocrystals (CNCs) offer enhanced functionality when incorporated into biopolymer matrices. Here, CNCs were irradiated with doses up to 50 kGy, leading to the formation of carboxyl and aldehyde groups, confirmed by FTIR analysis, as a consequence of the initial formation of free radicals and peroxides that may subsist in that original form or be converted into various carbonyl groups. Flexible films were obtained by incorporating pristine and EB-irradiated CNCs in an internal mixer, using minute amounts of poly(ethylene oxide) (PEO) to facilitate the dispersion of the filler within the polymer matrix. The resulting PLA/PEO/CNC films were evaluated for their mechanical, thermal, barrier, and antioxidant properties. The results showed that structural modifications of CNCs led to significant enhancements in the performance of the composite films, including a 30% improvement in water barrier properties and a 50% increase in antioxidant activity. These findings underscore the potential of irradiated CNCs as effective additives in biopolymer-based active packaging, offering a sustainable approach to reduce dependence on synthetic preservatives and potentially extend the shelf life of food products. Full article

Nanofiltration (NF) technology has extensive application in the treatment of wastewater generated in the dyeing industry. However, NF membranes often encounter fouling issues during the operation process. In this work, the superhydrophilic and self-cleaning multilayer nanofiltration membrane was prepared by self-assembling polyelectrolyte incorporating the anatase PSS-TiO₂ nanoparticles. The negatively charged PSS-TiO₂ nanoparticles were beneficial to the formation of the nanohybrid selective layers via electrostatic interforce. The prepared (PEI/PSS-TiO₂)_4.0 hybrid membrane showed favorable photoinduced superhydrophilicity. The water contact angle of the membrane decreased with the UV irradiation from 35.7° to 1.6°. The negatively charged (PEI/PSS-TiO₂)_4.0 membrane exhibited a 100% rejection rate to XO and EbT, with a permeance flux of 5.2 and 6.4 L/(m²·h·bar), respectively. After UV irradiation for 60 min, the permeance flux could be further increased to 13.4 and 14.0 L/(m²·h·bar), and the rejection remained at 97.8% and 96.7%. Owing to the low content of TiO₂ NPs photocatalytic effect under UV irradiation, the fabricated hybrid membrane exhibited a compromised permeance recovery of about 80.6%. Full article

A straightforward chemical polymerization process was used to create the polyaniline/LiClO₄/CuO nanoparticle (PLC) nanocomposite, which was then exposed to varying doses of electron beam (EB) radiation and studied. The FESEM, XRD, FTIR, DSC, TG/DTA, and electrochemical measurements with higher EB doses showed clear changes. The FTIR spectra of the PLC nanocomposite showed variations in the C-N and carbonyl groups at 1341 cm⁻¹ and 1621 cm⁻¹, respectively. After a 120 kGy EB dose, the shape changed from a smooth, uneven surface to a well-connected, nanofiber-like structure, creating pathways for electricity to flow through the polymer matrix. The EB irradiation improved the thermal stability by decreasing the melting temperature, and the XRD and DSC studies reveal that the decrease in crystallinity is attributed to the dominant chain scission mechanism. The enhanced absorption and red shift in the wavelength (from 374 nm to 400 nm) observed in the UV-Visible spectroscopy were caused by electrons transitioning from a lower to a higher energy state, with a progressive drop in the band gaps (E_g) from 2.15 to 1.77 eV following irradiation. The dielectric parameters increased with the temperature and electron beam doses because of the dissociation of the ion aggregates and the emergence of defects and/or disorders in the polymer band gaps. This was triggered by chain scission, discontinuity, and bond breaking in the molecular chains at elevated levels of radiation energy, leading to an augmented charge carrier density and, subsequently, enhanced conductivity. The cyclic voltammetry study revealed an enhanced electrochemical stability at a high scan rate of about 600 mV/s for the PLC nanocomposite with the increase in the EB doses. The I-V characteristics measured at room temperature exhibited nonohmic behavior with an expanded current range, and the electrical conductivity was estimated, using the I-V curve, to be around 1.05 × 10⁻⁴ S/cm post 20 kGy EB irradiation. Full article

Exchange-biased specimens were produced by molecular beam epitaxy (MBE) of ferromagnetic (FM) Co-on-CoO substrates after the substrates had been irradiated by heavy ions to induce defects in the antiferromagnet (AFM). Measurements were obtained at different temperatures for different sample orientations with respect to the external magnetic field. While the EB was relatively small, measurements of the bulk magnetization at low temperatures revealed unusually shaped hysteresis loops. The surface magnetization, however, showed simple, nearly rectangular hysteresis loops. This study focuses on the advantage of complementary information on surface and bulk magnetization from optical and non-optical measurement methods. Full article

Nowadays, volatile organic compounds (VOCs) increasingly jeopardize ecosystem sustainability and human well-being. In this study, UiO-66 and its different electron beam (EB) irradiation doses (100, 300, 500 kGy) modified materials supported Pt catalysts, Pt/UiO-66 and Pt/UiO-66-X (X = 100, 300, and 500, representing the irradiation doses), were synthesized, and a series of characterizations were conducted on the samples. On this basis, the effectiveness of these catalysts was evaluated through the degradation of ethyl acetate. The study findings indicated that the sample irradiated at 100 kGy demonstrated superior catalytic performance. Thereafter, extensive tests with regard to water resistance, stability, and cycle performance indicated that the Pt/UiO-66-100 catalyst was characterized by satisfactory reusability and catalytic stability, even when faced with high heat and humidity. Further work with in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and thermal desorption–gas chromatography–mass spectrometry (TD-GC–MS) uncovered the process of degradation of ethyl acetate. This research provides a guideline for the design of high-performance VOC degradation catalysts through EB modification. Full article

Herein, we synthesized Ti-MOF through a solvothermal method and subsequently calcined it to form anatase TiO₂. We further developed a Bi₂O₃@TiO₂ mixed oxide using impregnation and calcination processes. These oxides showed significant photocatalytic activity for degrading Eriochrome Black T (EBT) dye under visible light irradiation. We characterized the prepared samples using various techniques, including XRD, XPS, FTIR, BET, SEM, EDX, TEM, and UV-DRS analyses. Our results indicated that TiO₂ and 10%Bi₂O₃@TiO₂ achieved 80% and 100% degradation of EBT dye solution (50 ppm) within 30 min in acidic medium with a 50 mg catalyst dose, respectively. The calcination of the Ti-MOF into TiO₂ improved its sensitivity to visible light. The Bi₂O₃@TiO₂ composite was also effective in degrading other organic pollutants, such as Congo Red (degradation ~99%), Malachite Green (degradation ~95%), Methylene Blue (degradation ~81%), and Safranine O (degradation ~69%). The impregnation of Bi₂O₃ increased the surface acidity of TiO₂, enhancing its photocatalytic activity by promoting hydroxyl group formation through increased water adsorption. Additionally, 10%Bi₂O₃@TiO₂ demonstrated excellent chemical stability and reusability, maintaining high degradation efficiency over four cycles. Density Functional Theory (DFT) and Time-Dependent DFT (TD-DFT) calculations were performed to understand the degradation mechanisms. UV-Vis absorption spectrum simulations suggested that the anionic HEB⁻² (O24) or EB⁻³ forms of the EBT dye are likely to undergo degradation. This study highlights the potential of Bi₂O₃@TiO₂ composites for effective photocatalytic applications in environmental remediation. Full article

Diclofenac (DCF) degradation in aqueous solution under electron beam (EB) irradiation after nanobubbling treatment was studied and compared with treatments using nanobubbling or EB irradiation alone. It was found that the removal efficiency of DCF increased by increasing the adsorbed dose, and it depended on the initial concentration of DCF in solution, being higher for the lower concentrations. Furthermore, when using the nanobubbling treatment alone, about 16% of the DCF was removed from the aqueous solution due to the OH radicals generated during the process. On the other hand, using EB treatment at 0.5 kGy, the degradation of DCF increased from 36% to 51% when adding a nanobubbling pretreatment before the EB radiation. At higher doses (5 kGy), the degradation of DCF was 96% using EB radiation and 99% using nanobubbling before EB radiation, indicating that the nanobubbling effect was not synergistic. With an increase in the adsorbed doses, EB radiation seemed to play a more important role on the degradation of DCF, probably due to the reactive species generated. Moreover, the solutions treated with nanobubbling and EB radiation presented higher COD values and radiolytic by-products with aromatic rings with chlorine. This work can support the development of innovative strategies to treat municipal wastewaters using ionizing radiation technologies. Full article

In present times, with increasing emphasis on circular economies, municipal wastewater treatment plants (WWTPs) are considered resource recovery facilities. The targeted resources are water, biogas, and sludge, organic residuals containing nutrients and elements needed by plants (nitrogen and phosphorus). Sludge is a byproduct that constitutes the largest volume of all other byproducts obtained in wastewater treatment plants. Its processing and disposal are challenging for environmental engineers because of its complexity. Thus, quick development and implementation in industrial practice of sludge valorization and utilization technologies is required, where high nutrient content must be taken into account. Also, the occurrence of a variety of pathogens in sewage sludge is a matter of concern, even in the case of developed countries. The use of untreated sludge or wastewater in agricultural activities poses a serious risk of bacterial and parasitic infection in human beings. To overcome such issues, the application of ionizing radiation processing, especially electron beam (EB), can be considered a promising method. Its effectiveness in pathogen removal has been proven by researchers. Water radiolysis products created during irradiation of water are highly reactive and cause some effects such as DNA damage, ${}_{ }{}^{•}OH$ radical production, etc. Additionally, ionizing radiation technologies in sewage sludge treatment enhance the efficiency of the methane fermentation process. Depending on specific needs, different types of ionizing radiation sources can be discussed. Based on the review information and our research results, the basic engineering parameters of hybrid installation have been presented as the conclusion of the report. In this technical solution, a notably effective additional step would be the use of EB irradiation, combined with conventional wastewater treatment, to achieve efficient removal of pollutants. Full article

Electron beam–powder bed fusion (PBF-EB) is an additive manufacturing process that utilizes an electron beam as the heat source to enable material fusion. However, the use of a charge-carrying heat source can sometimes result in sudden powder explosions, usually referred to as “Smoke”, which can lead to process instability or termination. This experimental study investigated the initiation and propagation of Smoke using in situ high-speed synchrotron radiography. The results reveal two key mechanisms for Smoke evolution. In the first step, the beam–powder bed interaction creates electrically isolated particles in the atmosphere. Subsequently, these isolated particles get charged either by direct irradiation by the beam or indirectly by back-scattered electrons. These particles are accelerated by electric repulsion, and new particles in the atmosphere are produced when they impinge on the powder bed. This is the onset of the avalanche process known as Smoke. Based on this understanding, the dependence of Smoke on process parameters such as beam returning time, beam diameter, etc., can be rationalized. Full article