Search Results (1,215)

To investigate the polarization characteristics of AlO molecular emission in femtosecond laser-induced aluminum plasma, AlO molecular spectra were generated by irradiating an aluminum target with a femtosecond laser. The experimental results revealed a pronounced polarization response in the AlO emission. After a polarizer was introduced into the collection path, the signal-to-background ratio (SBR) increased from 8.30 to 10.80, while the relative standard deviation (RSD) decreased from 0.043 to 0.036, indicating improved spectral quality and stability. By modulating the laser polarization state using a half-wave plate and a quarter-wave plate, the AlO spectral intensity increased by a factor of 1.26 when the laser polarization was changed from horizontal to vertical, and by a factor of 1.75 when it was changed from linear to circular. Under circular, horizontal, and vertical polarization conditions, the SBR values obtained with a polarizer were consistently higher than those obtained without a polarizer, with the maximum value of 12.46 achieved under vertical polarization. These results demonstrate that both plasma polarization detection and laser polarization modulation can effectively achieve better-quality AlO molecular spectra. This work provides a useful reference for improving molecular spectral quality in femtosecond laser-induced spectroscopy. Full article

Effective thermal insulation of cryogenic liquid hydrogen (LH₂) storage tanks remains a critical engineering challenge, as conventional vacuum-based or monolithic systems are constrained by manufacturing complexity, mechanical vulnerability, and poor geometric adaptability. This study presents the design and numerical verification of a four-layer octagonal composite thermal shield fabricated via additive manufacturing: an AA5083 structural layer (5 mm), a boron nitride-doped ceramic plate (1 mm), up to 290 stacked graphene sheets in a sealed compartment, and an outer Fe₃S₄-TiO₂ nanocomposite layer (~30 µm). Steady-state and transient FEA in ANSYS evaluated three convective boundary conditions (h = 10, 15, and 20 W/m²·K), with the inner wall fixed at 20 K. Temperature distributions remained essentially invariant across all cases (20 K inner, ~20.12 K outer), confirming that thermal performance is governed by the multilayer architecture rather than convective intensity. The shield achieved a mean heat flux of 1684 W/m², R_total ≈ 0.163 m²K/W, and a boil-off rate of 13.9 g/hour. Comparative FEA against NASA US9617069 (q = 193.35 W/m²) and JP2018-119634A (q = 37.975 W/m²) highlights the compactness advantage of the proposed 6 mm shield; the coupled thermo-structural assessment yielded a safety factor of 64,182, confirming elastic-regime operation at 20 K. Full article

Solid-state sodium batteries based on polymer electrolytes offer a sustainable solution to overcome current and near-future needs regarding the growing energy and transport electrification issues. In this work, we propose the development of solvent-free polymer electrolytes based on an unsaturated polyether, which, once cross-linked, leads to an amorphous structure at room temperature that favors ionic transport towards reliable and robust solid-state sodium batteries operative at moderate temperatures. Using NaClO₄ and NaPF₆ as sodium salts, the best polymer electrolyte reaches an ionic conductivity in the range of 0.02 mS·cm⁻¹ (30 °C)–0.90 mS·cm⁻¹ (100 °C) with a lifetime superior to 2000 h after plating and stripping. Regarding electrochemical performance, a maximum specific capacity of 110.2 mAh·g⁻¹ (C/20) is obtained for the polymer electrolyte including NaClO₄, using Na and C/FePO₄ as anode and cathode, respectively, which represents about 65% of the theoretical value expected for FePO₄. In view of more sustainable energy storage devices, a life cycle assessment is also applied. While the polymer matrix is identified as the main environmental hotspot, the choice of Na salt significantly affects the overall impact, with NaClO₄ exhibiting lower climate change and particulate matter impacts than NaPF₆. Full article

Significance: This study addresses critical industrial and biomedical applications including glass blowing (thermal management of shrinking sheets), polymer sheet extrusion (controlled cooling), magnetic drug delivery (nanoparticle targeting), and nuclear reactor cooling (enhanced heat transfer). Aim: We present a novel nonlinear analysis of magnetohydrodynamic (MHD) boundary layer flow of a Jeffery Al₂O₃ nanofluid over a shrinking permeable plate with convective boundary conditions, uniquely integrating mixed convection, Ohmic dissipation, heat generation, Brownian motion, and thermophoresis within a non-Newtonian nanofluid framework. Methodology: The governing partial differential equations are transformed using similarity transformations and solved via the Adomian decomposition method (ADM). Comprehensive validation against RK4, RK45, and bvp4c demonstrates excellent agreement with maximum relative errors below $5\times {10}^{-4}$. Key Contribution: (i) Normal velocity decreases by 15–25% as the Biot number increases from $Bi=0.4$ to $0.6$; (ii) tangential velocity decreases by 20–30% as the magnetic parameter increases from $M=5$ to 15; (iii) temperature increases by 30–40% as the Eckert number increases from $Ec=0.5$ to $2.5$; (iv) ADM converges within 12–15 terms with $L_2$ errors $<{10}^{-5}$; (v) skin friction coefficient increases from $C_f=3.02713$ to $3.90082$ as $Q_0$ increases from 1 to 4; (vi) Nusselt number values: $Nu/\sqrt{Re}=0.4621$ at $Pr=0.7$, $0.8954$ at $Pr=2$, $3.2890$ at $Pr=20$. These quantitative findings provide design guidelines for engineers in thermal management and biomedical applications. Full article

To meet the requirements for passive heat dissipation and self-cleaning of aluminum alloy enclosures used in 5G base-station active antenna units (AAUs), a scalable surface modification strategy involving sandblasting, NaOH etching, and PFTEOS grafting was developed for 6061 aluminum alloy. Microscale rough structures were first constructed by sandblasting, and hierarchical micro/nano structures composed of microscale pits and nanoscale plate-like/coral-like features were subsequently formed through NaOH etching and boiling-water treatment. Finally, a low-surface-energy PFTEOS layer was grafted onto the structured surface to achieve superhydrophobicity. The effects of sandblasting pressure and etching time on surface morphology, chemical composition, wettability, and infrared emissivity were systematically investigated. The results show that sandblasting enhanced infrared emissivity by increasing surface roughness and promoting optical trapping, while NaOH etching further improved emissivity through the formation of hierarchical micro/nano structures and infrared-active AlOOH/Al₂O₃ phases. After PFTEOS grafting, the surface wettability changed from hydrophilic to superhydrophobic, while the high infrared emissivity was maintained. Compared with the untreated aluminum alloy, the modified surface exhibited a remarkable increase in water contact angle from 80.10° to 153.63° and infrared emissivity from 0.0102 to 0.8951. Moreover, the water contact angle remained above 150° after continuous water-jet impact, indicating good preliminary resistance to hydraulic shear. This work provides a feasible surface-engineering route for integrating high infrared emissivity and self-cleaning capability on aluminum alloy surfaces for outdoor thermal management applications. Full article

The NiO/Al₂O₃-CaO, CuO/Al₂O₃-CaO and CoO/Al₂O₃-CaO catalytic systems were investigated for the decomposition of ozone. Each of the three different Al₂O₃-CaO carriers was obtained after treatment of the initial precursor at 1100 °C for 2, 4 and 6 h, respectively, to examine the effect of annealing on support calcination. AAS, XRD, XPS, EPR, SEM and BET were applied for sample characterization. The carrier comprises a mixture of corundum α-Al₂O₃, θ-Al₂O₃ and Ca₃Al₂O₃. The XRD spectra of the active phases of the catalysts show the existence of Co₃O₄, NiO, Ni₂O₃ and CuO. The SEM micrographs reveal spherical particles for the NiO/Al₂O₃–CaO sample. In contrast, the CoO/Al₂O₃–CaO sample exhibits a morphology composed of wool-like fibers and perpendicularly oriented plate-like structures. The CuO/Al₂O₃–CaO sample consists not only of fibrous structures but also of distinct, separated aggregates. The obtained catalysts have highly developed specific surface areas. Their catalytic activity depends on the calcination conditions of the support, and the best results are observed after 2h treatment for all of the investigated samples due to the smaller crystallite size and higher specific surface area. The activity of the investigated catalysts for the ozone decomposition reaction follows the order NiO/Al₂O₃-CaO > CoO/Al₂O₃-CaO > CuO/Al₂O₃-CaO. Full article

Nanofluids, which are suspensions of nanoparticles within base fluids, are employed in industries such as electronics, automotives, nuclear power, and defense to enhance thermal management, mass transfer, and microchip cooling. This study investigates heat transfer generation on a stretching sheet incorporating aluminum oxide ${(\mathrm{A}\mathrm{l}}_2{\mathrm{O}}_3)$ and magnetite ${(\mathrm{F}\mathrm{e}}_3{\mathrm{O}}_4)$ nanoparticles under conditions of constant and varying wall temperatures. Key factors considered include variable viscosity, a periodic magnetic field, and thermal radiative flux, underscoring the thermal advantages of nanoparticles in nuclear reactor applications. The Crank–Nicolson method, an implicit finite difference technique, was utilized to solve the mathematical model, with partial differential equations discretized and approximated using an explicit method. An explicit iterative method was employed to solve the momentum and energy equations in a Python solver, while boundary values were analytically resolved based on discretized equations. In the explicit method, values at the subsequent time step (n + 1) were directly computed from the current time step (n) values. This approach necessitated a sufficiently small time step to satisfy the Courant–Friedrichs–Lewy (CFL) condition for numerical stability. The study examined the mass and heat transfer characteristics of a magnetizable nanofluid. While nanoparticles enhanced heat transfer, magnetic interactions, viscosity, and thermal radiation impeded it. A periodic magnetic field was applied perpendicularly to the plates with a constant pressure gradient, utilizing a magnetic phase angle to decelerate and control flow and heat convection modulation. Full article

Electrochemical oxidation (EO) possesses numerous advantages and great potential for organic pollutant degradation. However, traditional plate anodes for EO are limited by pollutant mass transfer, leading to low oxidation efficiency and high energy consumption. Herein, a three-dimensional (3D) polyacrylonitrile-based carbon fiber brush (PAN-CFB) anode was employed to enhance mass transfer and improve oxidation efficiency. The oxidation capacity of the PAN-CFB anode was compared with those of boron-doped diamond (BDD) and Ti/IrO₂-Ta₂O₅ plate anodes using oxalic acid (OA), phenol, and perfluorooctanoic acid (PFOA) as target pollutants, respectively. Experimental results demonstrated that the 3D PAN-CFB anode exhibits superior direct oxidation capacity compared to BDD and the Ti/IrO₂-Ta₂O₅ plate anode in degrading OA, which is attributed to the significantly enhanced mass transfer of OA toward the brush anode surface. Under a constant current of 400 mA for 240 min, the total organic carbon (TOC) removal from 50 mmol/L OA reached 90.5%, 57.5% and 6.6% for PAN-CFB, BDD and the Ti/IrO₂-Ta₂O₅ anode, respectively, and the energy consumption followed the order of PAN-CFB (5.5~8.9 kWh/kg_TOC) < BDD (11.2~19.3 kWh/kg_TOC) < Ti/IrO₂-Ta₂O₅ (76.1~120.7 kWh/kg_TOC). However, the 3D PAN-CFB anode exhibited poor stability at high potential and failed to promote phenol and PFOA degradation due to the weak direct oxidation capacity toward the two pollutants and the poor generation capacity of reactive oxygen species, associated with its low oxygen evolution potential. Therefore, future efforts should focus on developing stable 3D brush electrodes with a higher oxygen evolution potential to enable non-selective oxidation of a broader range of pollutants. Full article

Foot-and-Mouth Disease (FMD) is caused by the FMD virus. Indirect Sandwich Enzyme-Linked Immunosorbent Assay (IS-ELISA) was standardized to characterize the FMD serotype “O” virus. Total protein content in the guinea pig serum (whole serum), ammonium sulfate precipitated guinea pig serum (ASPGPS) protein and ion-exchange-based purified guinea pig serum (IEGPS) protein was measured as 52 µg/mL, 24 µg/mL and 10 µg/mL respectively. The whole serum of guinea pigs and rabbits showed the 1:32 and 1:64 anti-FMD serotype “O” virus neutralizing antibody titers, while the anti-FMD serotype “O” virus neutralizing antibody titer was 1:128 in the IEGPS proteins. IEGPS protein with 1:128 neutralizing antibody titers were used as capture/trapping antibodies in the standardization of the assay. The IEGPS protein 1:1000 diluted with 10 µg/mL of protein content was found to be optimum for capture/trapping antibodies. To cover residual blank spaces, different available blocking buffers were evaluated and Skimmed Milk Solution 5% in Phosphate-Buffered Saline (PBS5%) proved best amongst blocking buffers. Coating of 1:1000 diluted IEGPS at 37 °C for 1 h followed by storage at 4 °C for overnight was best for incubation time. FMD serotype “O” virus 1:100 diluted was optimum in IS-ELISA. Similarly rabbit anti-FMD serotype “O” virus specific immune serum 1:10,000 diluted and goat anti-rabbit IgG horseradish peroxidase conjugate 1:4000 diluted were found to be optimum during the standardization of the assay. Lastly ELISA plates proved to be best amongst the available plates for assay. In each experiment, the plateau region, test background and plate background were recorded. Lastly it became possible for the establishment of an optimized and potentially cost-effective IS-ELISA requiring further diagnostic validation in research and diagnostic laboratories in the country. Full article

With the growing demand for strategic metals and the gradual depletion of traditional metal ore deposits, coal and coal-bearing strata are regarded as potential sources of rare metals; consequently, research into the characteristics of associated elements in coal-bearing strata has become one of the primary avenues of searching for new alternative resources. To investigate the sedimentary environmental characteristics and controlling factors of the coal-bearing strata along the southern margin of the Junggar Basin, coal seams 9–15 of the Xishanyao Formation in Sulphur Gully (Early Middle Jurassic) were selected as the subject of this study. This study employed analytical techniques including industrial analysis, total sulphur analysis, X-ray powder diffraction (XRD), X-ray fluorescence spectroscopy (XRF) and inductively coupled plasma mass spectrometry (ICP-MS) to determine the mineralogical and elemental geochemical characteristics of coal samples from Seylangou mining area, specifically from coal seams 9–15 and their overlying and underlying strata. Based on analyses of elemental ratios such as Al₂O₃/TiO₂, Sr/Ba, Rb/Sr, Ni/Co and V/(Ni + V), the source of material during the deposition of this deposit was identified, and the characteristics of the depositional environment, as indicated by palaeosalinity, palaeoclimate and redox conditions, were revealed. The results indicate that the macroscopic coal-rock types of coal seams 9–15 at the Sulphur Gully Coal Mine on the southern margin of the Junggar Basin are predominantly semi-dull to dull, with small amounts of filamentous coal and lustrous coal. The average proportion of the vitrinite group in the coal is 42.75%, the inertinite group is 51.40%, and the liptinite is 2.25%. The average content of inorganic matter in the coal is 3.60%, and the average maximum reflectance of the vitrinite group is 0.651%. The coal represents a transitional stage from low-rank to medium-rank coal, corresponding to a metamorphic stage of Grade I–II. The coal is classified as a bituminous coal with medium total moisture, very low ash, medium-volatile matter, medium-to-high fixed carbon and very low sulphur. The minerals in the coal seam are predominantly kaolinite, calcite and quartz. The major elements in the ceiling of the coal seam are dominated by SiO₂, followed by Al₂O₃; the coal itself is dominated by CaO, SiO₂ and Al₂O₃; and the base plate of the coal seam is dominated by Al₂O₃. The trace elements Cs and Bi are relatively enriched in the coal seam ceiling; Sr is relatively enriched in the coal; whilst Li, Cr and other elements are highly enriched in the coal seam base plate. The source rocks of the coal and the roof consist of deposits of felsic igneous rock (dacite), whilst the source rocks of the floor consist of deposits of intermediate igneous rock (andesite). The depositional environment ranges from marine brackish water at the base to transitional slightly brackish water and then to terrestrial freshwater at the top; the depositional climate was cold and arid, and the depositional environment was oxidising. This study provides valuable insights for further research into the elemental geochemical characteristics, sediment sources and depositional environments of the Xishanyao Formation coal seams in Liuhuangou, Xinjiang. Full article

Ochetobibus elongatus (Kner) is a migratory fish found in the Yangtze River basin and areas south of it, and listed as a critically endangered (CR) fish on the China Red List of Vertebrates. To achieve group recovery and artificial breeding, this study investigated the dietary characteristics of O. elongatus based on high-throughput sequencing of its intestinal contents, and its digestive system morphology, and its histology. Results showed that the digestive system of O. elongatus lacked a stomach and mainly consisted of the oropharynx, pharyngeal teeth, esophagus, intestine, and anus. The gut index was 0.88, with clear segmentation of the foregut, midgut, and hindgut, and the visceral mass index was 7.35%. Histological analysis of the digestive system revealed the presence of keratinized dental plates or pharyngeal teeth in the pharynx, as well as a high density of taste bud cells in the soft palate of the oral cavity. The surface layer of the intestinal villi contained numerous mucous cells, with the average number of mucous cells per villus gradually increasing from the esophagus to the hindgut, and the foregut having the longest and most abundant mucosal folds. The esophagus exhibited well-developed circular and longitudinal muscle layers, while in the hindgut, both the circular and longitudinal muscle layers were slightly thicker than those in the midgut. High-throughput sequencing of the intestinal contents of O. elongatus revealed the following phyla based on 18S V4 meta-barcoding: Chlorophyta, Diatoms, Arthropoda, Basidiomycetes, and Ascomycetes, with the genus Hypophthalmichthys and algae being the main classifications. In contrast, based on COI meta-barcoding, the study newly identified the phyla Cnidaria and Mollusca, with the genera Chlorophyta, Scenedesmus, Pectinodesmus, and zooplankton such as Pseudodiaptomus. Metagenomic sequencing revealed that the gut microbiota at the phylum level was predominantly composed of Pseudomonadota, Ascomycota, Basidiomycota, Chytridiomycota, and Bacillota, with key genera including Cetobacter, Pseudomonas, Acinetobacter, Aeromonas, and Clostridium. This study indicates that O. elongatus is an omnivore with carnivorous tendencies. Basic biological research on O. elongatus is of great significance for the restoration of the population, artificial breeding, and the development of its artificially formulated feed. It also provides important data for the formulation of biodiversity conservation measures. Full article

Controlling the microstructure of electroless nickel coatings is crucial for optimizing the interfacial properties of carbon fibers. However, a systematic understanding of how dispersants can effectively leverage the refining effect of nanoparticles in composite plating systems remains lacking. This paper proposes the use of a composite dispersant, comprising polyethylene glycol (PEG) and sodium methylene bis-naphthalene sulfonate (NNO) at a 1:1 mass ratio, for nano-Al₂O₃ to achieve microstructure refinement of nickel coatings on carbon fiber surfaces. The results demonstrate that the composite dispersant modifies the surface state and dispersion stability of Al₂O₃ particles through synergistic adsorption, thereby regulating the nucleation and growth behavior of the Ni-P alloy. At an optimal composite dispersant concentration of 3 g/L, the coating exhibits the most compact structure, with Ni-P particle size refined to approximately 181 nm. The coating consists of two phases: crystalline Ni₃P and amorphous Ni-P. The dual adsorption effect of the dispersant—inhibiting Al₂O₃ agglomeration while improving the surface wettability of carbon fibers—is key to enhancing the refinement efficiency. Conversely, excessive dispersant addition leads to deteriorated coating quality. This study provides experimental evidence for understanding the multiphase interfacial interaction mechanism involving organic additives, nanoparticles, and metal deposition, and offers a novel strategy for controlling the surface functionalization of carbon fibers. Full article

Efficient thermal management is critical for maintaining the safety, durability, and performance of lithium-ion batteries used in electric vehicles (EVs). In this study, a comprehensive numerical investigation is conducted to evaluate the heat transfer characteristics of mono- and hybrid-nanofluids in a microchannel-cooled lithium-ion battery module. A three-dimensional computational model of a 5S7P battery module composed of cylindrical 21700 cells is developed. Battery heat generation during 3C high discharge rate operation is predicted using the Newman-Tiedemann-Gu-Kim (NTGK) electrochemical model, while coolant flow and heat transfer are simulated using the governing conservation equations for mass, momentum, and energy. The cooling system consists of six liquid-cooling plates with circular microchannels. The performance of water-glycol (50/50) coolant is compared with several mono nanofluids of Al₂O₃ and Cu, and hybrid nanofluids of Al₂O₃-Cu, Al₂O₃-MWCNT, Al₂O₃-Graphene, Cu-MWCNT, and Cu-Graphene across multiple coolant flow rates from 1–5 LPM. The results demonstrate that nanofluids significantly enhance convective heat transfer and reduce battery temperature compared with the conventional water-glycol coolant. Among the investigated coolants, the Al₂O₃-Cu hybrid nanofluid (0.45–0.45%) operating at 1 LPM achieves the best overall thermo-hydraulic performance with a performance evaluation criterion (PEC) of 1.065. Further analysis of nanoparticle composition ratios shows that a Cu-dominant hybrid mixture (Al₂O₃-Cu: 0.27–0.63%) slightly improves the PEC to 1.0657, indicating marginally superior cooling performance. The findings highlight the potential of hybrid nanofluids as advanced coolants for microchannel-based battery thermal management systems in EVs, particularly under moderate coolant flow conditions. Full article

Small long-lifetime pressurized water reactors (PWRs) impose higher requirements on the reactivity compensation capacity, power distribution control precision, and long-term burnup adaptability of burnable poisons due to their compact core volume and extended operational lifetime demands. Traditional experience-dependent design of burnable poison combinations struggles to balance multi-objective requirements and easily overlooks the compatibility of different burnable poison combinations, leading to issues such as uneven reactivity release, excessive fluctuations, or insufficient burnup depth in the designed schemes. To address these challenges, this study introduces the reference point-based non-dominated sorting genetic algorithm (NSGA-III) into the optimization design of burnable poison material combinations for small long-lifetime PWRs. Combined with deterministic methods, a multi-objective optimization model is established with core objectives, including controlling initial excess reactivity, reducing reactivity fluctuations, and improving burnup depth. The decision variables include the types of burnable poison materials, their combination ratios, the arrangement of poison-containing fuel plates, and the loading form of the burnable poisons. The calculation results show that the combination of Gd₂O₃ and B₄C exhibits the best comprehensive performance as burnable poisons; the combined application of Er₂O₃, Eu₂O₃, Sm₂O₃, ²³¹Pa, ²⁴¹Am, ²⁴⁰Pu, and ²³⁷Np requires further research in conjunction with core schemes; and Dy₂O₃ is not suitable as a burnable poison combination material. Full article

Muskmelon (Cucumis melo) is a widely cultivated and economically important fruit crop that is severely affected by Fusarium wilt caused by Fusarium oxysporum f. sp. melonis (race 1.2) (Fom). Conventional management practices have shown limited effectiveness and pose environmental and health risks; therefore, sustainable and eco-friendly alternatives are required to manage this disease. In the present study, 23 endophytic fungal isolates belonging to eight genera were isolated from Ecballium elaterium and screened to determine antifungal potential against Fom using an in vitro antagonistic assay. Two endophytic isolates (Fusarium sp. EeR4 and Fusarium clavum EeR24) exhibited an inhibitory effect against Fom on quarter-strength PDA plates. In growth chamber experiments, F. clavum EeR24-colonized melon seedlings and significantly protected plants from wilting compared to non-colonized pathogen-challenged seedlings. Under greenhouse conditions, F. clavum EeR24 significantly improved morphological and physiological traits, including plant height, weight, number of leaves, membrane stability, photosynthesis, stomatal conductance, and transpiration, in Cucumis melo. Endophytic colonization improved catalase (56%), guaiacol peroxide (47%), and superoxide dismutase activity (25%), and increased flavonoid and phenolic content by 11–59% compared to non-colonized Fom-challenged plants. Lipid peroxidation significantly decreased by 37% and proline accumulation increased by 70% in colonized plants compared to non-colonized plants. Histochemical analysis also indicated that endophytic colonization considerably reduced the levels of H₂O₂, O₂⁻, malondialdehyde, and cell mortality in Fom-challenged plants. In addition, the culture filtrate and organic residues of F. clavum EeR24 inhibited the mycelial growth of Fom by 52–58%, respectively. Furthermore, a study on spatial colonization of the endophyte and the pathogen using GFP and RFP tagging indicated that both the endophyte and the pathogen simultaneously colonized the root tissues of C. melo; however, the endophyte significantly reduced the pathogenicity of Fom. These results suggest that endophytic F. clavum EeR24 may be developed as an effective biocontrol agent for the management of Fusarium wilt in melon plants under field conditions. Full article