Search Results (24,816)

This work investigates the fabrication and performance of axially compressed isotropic epoxy-bonded NdFeB-type magnets produced from melt-spun powders with partial substitution of (Nd,Pr) by (La,Ce). Four alloy compositions were synthesized and processed into bonded magnets using two powder-to-binder weight ratios (95:5 and 96.5:3.5). Structural analysis confirms that all substituted alloys retain the tetragonal Nd₂Fe₁₄B phase (up to ~95 wt%) even at high substitution levels, while the lattice parameters decrease slightly with increasing (La,Ce) content. Microscopy analysis confirms a homogeneous distribution of the binder phase around the powder particles, demonstrating uniform binder–powder integration. Thermal analysis reveals composition-dependent Curie temperatures and enhanced crystallization onset in highly substituted powders. Magnetic measurements on both powders and bonded magnets show that increasing substitution leads to a gradual reduction in remanence, coercivity, and energy product, though all samples maintain strong hard-magnetic behavior. Increasing the powder fraction to 96.5 wt.% significantly improves all magnetic parameters due to higher magnetic-phase density and enhanced interparticle coupling, yielding bonded magnets with densities up to ~80% of the theoretical value. The resulting magnets achieve competitive performance, uniform field distribution and isotropic magnetization with (BH)max values about 65 kJ/m³, a coercivity around 660 kA/m, and superior thermal stability compared with commercial bonded NdFeB magnets. Overall, partial substitution with light rare-earth elements (La,Ce) provides a cost-effective route to high-density bonded NdFeB magnets that combine strong magnetic performance, enhanced thermal stability, and suitability for lightweight, complex-shaped industrial applications. Surprisingly, the coefficients of the temperature variation of coercivity and (BH)_max are much better compared to the commercial NdFeB bonded magnets. Full article

The accelerating transition to low carbon energy systems has intensified the demand for nickel and cobalt from low-grade (<1.5 wt.%) refractory lateritic ores. These low-grade laterites are however not amenable to conventional beneficiation due to their complex mineralogy, eclectic physicochemical properties, and fine Ni–Co dissemination. This review examines recent advances made in the extraction of nickel and cobalt from complex low-grade lateritic ores, emphasizing the interplay between ore mineralogy, chemistry, beneficiation, pretreatment, and processing route selection. Developments in selective ore comminution–classification have led to the generation of Ni-rich fine fractions (undersize) and Co-rich coarse fractions (oversize), enabling differentiated extraction strategies that improve resource utilization, frugal energy use, and process efficiency. Mechanical activation via stirred media milling, thermal calcination-induced structural disorder, and dehydroxylate goethite products, are shown to significantly enhance Ni–Co leaching kinetics under both atmospheric and heap leaching conditions. A critical comparison of pyrometallurgical (rotary-kiln electric furnace) and hydrometallurgical (HPAL, EPAL, heap, atmospheric, bioleaching) routes demonstrates that ore-specific optimization is essential to balance recovery, acid consumption, and greenhouse gas emissions. The novel resin in moist mix (RIMM) process, which integrates ambient leaching and in situ ion exchange selective recovery, is shown to offer potential for sustainable values extraction from sub-economic resources. Furthermore, the review highlights the key innovation challenges and concomitant opportunities for enhanced critical battery metal recovery from complex laterite ores. Full article

Vibrio anguillarum is a major pathogenic bacterium causing vibriosis in aquatic animals, leading to substantial economic losses in the global aquaculture industry. Previous studies have indicated that L-arginine modulates the virulence of the pathogen, but the underlying molecular mechanisms remain elusive. The present study aimed to clarify the regulatory role of L-arginine metabolism in V. anguillarum virulence. We first evaluated the effects of L-arginine and its major metabolites (agmatine, putrescine, spermine) on the hemolytic activity of V. anguillarum. Results showed that L-arginine and its metabolites regulated hemolytic activity in a concentration-dependent biphasic manner, with agmatine exerting the most potent promoting effect. To identify the critical metabolic branch involved, four isogenic mutants were constructed targeting key genes in arginine metabolism (adc, astA, astD). Phenotypic analysis revealed that only the adc deletion mutant (Δadc) exhibited near-complete loss of hemolytic activity, which was dose-dependently restored by supplementation with agmatine, putrescine, or spermine. Transcriptomic analysis identified 704 significantly differentially expressed genes (DEGs) between Δadc and WT strains, with downregulated DEGs enriched in virulence-associated pathways. Key hemolysin and secretion system genes were validated to be downregulated in ∆adc by quantitative real-time PCR (qRT-PCR). Additionally, Δadc displayed attenuated anti-phagocytic ability in Tetrahymena co-culture assays, impaired biofilm formation, and increased susceptibility to multiple classes of antibiotics. Collectively, our findings demonstrate that L-arginine modulates V. anguillarum hemolysis and overall virulence through the adc-mediated agmatine biosynthesis branch. This study fills the knowledge gap in the regulatory mechanism of L-arginine on V. anguillarum virulence and provides a potential target for the control of vibriosis in aquaculture. Full article

Given the increasing burden of diet-induced metabolic dysregulation, preventive nutritional strategies targeting early insulin resistance are of growing interest. The aim of this study was to evaluate the effects of white tea supplementation on body weight gain, insulin resistance, and the Gremlin-1/Bone Morphogenetic Protein-4 (BMP-4) axis in visceral adipose tissue under high-fat diet conditions in a non-obese experimental model. Thirty-two male Sprague–Dawley rats were randomized into four groups (n = 8/group): standard diet (control), only high-fat diet (HFD), high-fat diet plus orlistat (ORL: 30 mg/kg/day), and high-fat diet plus white tea (WT: 5 mg/kg/day). Interventions were administered once daily by oral gavage for 12 weeks. Body weight was recorded weekly. At the end of the study, serum insulin, Gremlin-1, and BMP-4 and retroperitoneal adipose tissue Gremlin-1 and BMP-4 levels were measured by ELISA. Adipose tissue GREM1 gene expression was quantified by qRT-PCR. Insulin resistance was estimated using the HOMA-IR index. Appropriate statistical analyses were conducted in line with the study design and data distribution. High-fat feeding resulted in the highest HOMA-IR values, whereas white tea supplementation reduced HOMA-IR compared to the HFD group (p = 0.008). Body weight gain was increased in both the HFD and ORL groups compared to the control (p = 0.009 and p = 0.012, respectively). The lowest weight gain was observed in the WT group, which was lower than the HFD group (p = 0.044). GREM1 expression showed a 1.92-fold increase in the HFD group relative to the control, with smaller increases in the WT and ORL groups; however, intergroup differences did not reach statistical significance (p = 0.063). Serum BMP-4 levels were lower in the WT group compared to the control (p = 0.012), while tissue BMP-4 and Gremlin-1 levels did not differ between groups. Correlation analyses revealed a moderate inverse association between serum Gremlin-1 and serum BMP-4 (rho = −0.493, p = 0.011) and a moderate positive correlation between serum BMP-4 and HOMA-IR (rho = 0.564, p = 0.003). White tea supplementation attenuated body weight gain and preserved insulin sensitivity in a non-obese high-fat diet model, as evidenced by reduced weight gain and lower HOMA-IR values compared with high-fat feeding alone. These metabolic improvements were accompanied by coordinated changes in circulating components of the Gremlin-1/BMP-4 axis, including reduced serum BMP-4 levels and associations between BMP-4, Gremlin-1, and insulin resistance. Although tissue-level alterations were modest, the observed systemic patterns are consistent with an exploratory association between white tea intake and early metabolic signaling changes; however, definitive pathway modulation cannot be inferred from the present dataset. Collectively, these findings support white tea as a nutrient-derived bioactive with preventive metabolic potential during the early stages of diet-induced metabolic dysregulation, prior to the development of overt obesity. Full article

The Upper Triassic Xujiahe Formation (T₃x) represents a critical terrestrial source rock system in the Sichuan Basin, exhibiting pronounced vertical and lateral heterogeneity. Previous stratigraphic subdivisions relied primarily on lithological correlations rather than a systematic sequence stratigraphic framework. This approach has led to significant inconsistencies in source rock evaluation. Furthermore, recent discoveries of large gas fields, coupled with data from newly drilled wells, necessitate a comprehensive reassessment of this system. In this study, we re-evaluate the geochemical characteristics and spatial distribution of these source rocks within a newly established sequence stratigraphic framework. This assessment utilizes a robust dataset comprising total organic carbon (TOC) content, Rock-Eval pyrolysis, and vitrinite reflectance (Ro) measurements. The results indicate that the source rocks of the New Member 5 (T₃x⁵) in the slope belt of Central Sichuan exhibit the highest hydrocarbon generative potential. These rocks are characterized by high organic abundance (with 40% of samples showing TOC ≥ 2.0 wt.%), are dominated by Type III and II₂ kerogen (humic–sapropelic), and have reached the mature to high-maturity stage (Ro ranging from 1.0% to 1.7%). Notably, the cumulative thickness of these high-quality source rocks reaches 100~150 m. Specifically, the T₃x⁵ intervals in the Qiulin and Tianfu areas are identified as the most favorable hydrocarbon-generating centers. This reassessment under the new stratigraphic division provides a refined theoretical basis for future exploration targeting the Xujiahe Formation in the Sichuan Basin. Full article

The Nanping pegmatite-type Nb-Ta deposit is one of the large-scale Li-Cs-Ta (LCT)-type pegmatite deposits in Southeast China. Nevertheless, the mineralization mechanism of this ore deposit remains unclear, primarily due to the lack of systematic research on the characteristics of ore-forming fluids and mineralization processes. To address this issue, analyses of the fluid inclusion characteristics, hydrogen–oxygen isotope compositions and in situ U-Pb geochronology of Nb-Ta minerals were performed on the No. 31 vein of the Nanping pegmatite deposit. In situ U-Pb dating of the Nb-Ta minerals with varying textures from different zones yields main mineralization ages clustered between 390 and 370 Ma, along with isolated younger ages around 270 Ma in specific mineral zones, indicating multiple mineralization episodes. The fluid inclusion homogenization temperatures of different zones range from 130 to 382 °C, and salinities between 2 and 16 wt% NaCl eqv, consistent with a medium-to-low temperature and salinity fluid system. Hydrogen and oxygen isotope data show that the ore-forming fluids were predominantly derived from magmatic fluids, mixed with later meteoric waters. This study clarifies the multistage mineralization history and fluid evolution of the Nanping pegmatite-type Nb-Ta deposit, providing key constraints for metallogenic models of pegmatite-hosted rare-metal deposits. Full article

Background/Objectives: TP53 mutation or deletion status is important for determining cellular responses to DNA-damaging drugs. Oxaliplatin (OXA) is combined with the fluoropyrimidine (FP) drug 5-fluorouracil (5-FU) in the FOLFOX regimen used to treat advanced colorectal cancer (CRC). However, the effects of TP53 deletion on 5-FU + OXA synergy are not well known. We investigated potential synergy between OXA and 5-FU and compared it with OXA synergy with a novel polymeric FP, CF10, in four cell lines harboring either wild-type (WT) or TP53-null status. Methods: Using CompuSyn and the highest single agent (HSA) models, we compared synergy between CF10 and OXA (COXA) and between 5-FU and OXA (FOXA). Cell cycle analysis was performed, as was Western blot quantification of canonical DNA damage pathway proteins. Likewise, immunofluorescent and confocal analysis allowed us to compare topoisomerase 1 cleavage complex and double-strand DNA break formation. Results: COXA synergy displayed minimal TP53 dependence with greatly improved potency compared to FOXA. COXA synergy resulted from OXA increasing: (i) Topoisomerase 1 (Top1) cleavage complex formation; (ii) DNA double-strand breaks (DSBs), and (iii) Checkpoint Kinase 1 and 2 (p-Chk1/2) phosphorylation, consistent with increased replication stress. Additionally, increased S-phase entry in TP53-null cells enhanced synergy between CF10, 5-FU, and OXA as S-phase drugs. Conclusions: Our results demonstrate that OXA synergizes with CF10 more effectively than with 5-FU through enhanced replication stress in both WT and TP53-null cells by causing greater Top1-mediated DNA double-strand breaks. Our studies provide a foundation for further testing of this combination in an orthotopic liver metastatic setting and eventual clinical development. Full article

This paper builds a one-dimensional transient numerical model of mixed fuel of woody and non-woody biomass to simulate the multistage conversion process of biomass in a moving grate-fired bed, including drying, pyrolysis, gasification, and char combustion. Based on time and space discretization, the model comprehensively considers the conservation of mass, momentum, and energy. It also introduces reaction kinetics and freeboard radiation coupling effects to more accurately describe the bed temperature distribution and reaction process. The analysis focuses on the effects of different non-woody biomass mixing ratios and moisture content. This provides references for optimization of the design of future furnaces and operating parameters and mixed fuel composition. The simulation results show that, for pure woody biomass, the surface temperature reaches approximately 200 °C in the first zone, followed by char reactions with peak temperatures up to 592 °C. The whole conversion process takes about 62% of the grate length. Increasing the pepper mixing ratio leads to lower bed temperatures due to the higher moisture content. The maximum bed temperature in the first zone decreases from 592 °C for pure wood to 551 °C at 30 wt.% pepper, with delayed pyrolysis and a thinner char reaction zone. When the pepper mixing ratio is below 20 wt.%, the combustion process maintains a stable temperature gradient and a continuous reaction front, compared to the mixing ratio of 30% pepper case. This confirms the feasibility of non-woody biomass application to combustion technology. Although a higher pepper mixing ratio leads to a slight temperature decrease, the reaction remains stable along the grate, indicating reliable combustion performance. Full article

Glycidyl azide polymer (GAP)-based polyurethane, a kind of energetic thermoplastic elastomer (ETPE), is a promising binder for advanced solid propellants, but its thermal decomposition involves overlapping competitive reactions that conventional single-step kinetic models cannot characterize accurately, limiting its engineering applications. To address this limitation, a constrained asymmetric Gaussian deconvolution strategy with fixed peak area ratios and shape constraints was developed in this work. This strategy was applied to resolve overlapping reaction rate curves converted from derivative thermogravimetric data of GAP-based ETPEs with 50 wt% GAP content at four heating rates of 5, 10, 15 and 20 K·min⁻¹. The complex decomposition process was successfully split into five stages, assigned to azide cleavage, polyether backbone scission, carbamate cleavage, hydrocarbon product degradation and residue decomposition, with a goodness of fit of R² > 0.998. Apparent activation energies of the five stages were determined through cross-validation by the Friedman and Flynn–Wall–Ozawa methods without prior assumption of reaction mechanisms, following the order of residue decomposition (181.4 ± 1.0 kJ·mol⁻¹) > hydrocarbon product degradation (159.9 ± 1.0 kJ·mol⁻¹) ≈ azide cleavage (156.5 ± 0.6 kJ·mol⁻¹) > backbone scission (135.1 ± 0.7 kJ·mol⁻¹) > carbamate cleavage (111.9 ± 1.1 kJ·mol⁻¹). Pre-exponential factors with lnA₀ values ranging from 22.2 to 34.0 were derived via the kinetic compensation effect. Finally, generalized master plots were employed to compare with classic solid-state reaction models for mechanistic insight, and the Šesták–Berggren model fit three major stages excellently (R² > 0.996) by accounting for synergistic nucleation-growth and phase boundary mechanisms, enabling high-precision kinetic equations. It should be noted that the constrained deconvolution method proposed in this work has general applicability for kinetic analysis of GAP-based ETPEs with different formulations and other complex energetic polymer systems, while the obtained kinetic parameters are composition-specific and only applicable to the corresponding ETPE formulation studied herein. Full article

Dried okara (DOK), a lignocellulosic byproduct from tofu production, was evaluated as both a carbon source and culture medium to enable cost-effective polyhydroxybutyrate (PHB) production. Hydrolysis with either HCl or H₂SO₄ generated 48–51 g/L reducing sugars with peak values reaching 60.2 g/L using 3% acid at 121 °C. Analysis of monosaccharides indicated pentoses, especially xylose, as the main sugars present. A novel strain, Burkholderia sp. EP10 exhibited direct growth and PHB accumulation in DOK hydrolysate without requiring detoxification, tolerating inhibitory compounds such as furfural and 5-hydroxymethylfurfural. In shake flask experiments, the strain achieved 6.9 g/L biomass and 26.3 wt% PHB, while in fermentor studies, biomass reached 10.9 g/L and PHB content was 29.3 wt% at a C/N ratio of 5.7. Notably, these outcomes were achieved without pH control, constituting a key benefit for operational simplification and cost minimization. The biopolymer was verified as PHB using gas chromatography, Fourier transform infrared spectroscopy, and proton nuclear magnetic resonance spectroscopy. The PHB displayed melting transitions at 163.5 and 172.4 °C, a degradation onset at 268 °C, and high molecular weight (4.66 × 10⁵ Da). Burkholderia sp. EP10 for sustainable PHB production via direct bioconversion of lignocellulosic hydrolysates, without the need for pH adjustment, detoxification, or complex medium development. Full article

The growing demand for wearable electronics and the Internet of Things (IoT) calls for flexible piezoelectric energy harvesters with substantially improved power output. Polyacrylonitrile (PAN) polymers, with their high polarization and excellent thermal stability, are among the most promising candidates for efficient flexible piezoelectric materials. However, the performance of existing PAN-based harvesters remains limited, and strategies for further enhancing their output are still insufficiently explored. Herein, this study aims to overcome the output bottleneck of PAN-based PENGs by implementing a novel mechanical excitation strategy. Using electrospun flexible PAN-BaTiO₃ nanocomposite films, we systematically compared the electromechanical responses under conventional compression and impact modes. Real-time synchronized force–current measurements in compression mode revealed that the output current increases progressively with drive frequency (2–10 Hz). Specifically, the PENG with PAN-20 wt.% BaTiO₃ achieved a peak current of 0.33 mA at 10 Hz, showing an approximately 7.9-fold enhancement over its pure PAN counterpart. More importantly, under 6 Hz impact excitation, the device exhibited a remarkable output current density of 1.0 mA cm⁻² and a peak power density of 256.5 µW cm⁻². This current density is 95 times higher than that in compression mode at a comparable frequency and surpasses the performance of most recently reported piezoelectric and triboelectric nanogenerators. With an effective area of 16 cm², the PENG could simultaneously illuminate up to 275 commercial LEDs or 100 individual bulbs and maintained stable operation over 63,530 cycles. This work overcomes the output bottleneck in low-frequency energy harvesting and provides an effective pathway toward practical energy-harvesting applications. Full article

Polymer–ceramic composites based on cyanate ester resins have attracted increasing attention for high-frequency electronic applications due to their low dielectric loss, thermal stability, and dimensional reliability; however, achieving a targeted dielectric constant while maintaining low loss remains a key challenge. In this study, transparent glass powders and BaTiO₃ ceramic fillers were incorporated into a cyanate ester matrix to systematically investigate structure–property relationships and optimize dielectric performance for antenna-related applications. Transparent glass powders were synthesized via a melt-quenching route and combined with submicron BaTiO₃ particles, while both fillers were surface-modified using 3-triethoxysilylpropyl isocyanate (TESPI) to enhance interfacial compatibility. Composite samples containing 5–30 wt% total filler were fabricated and characterized by XRD, FTIR, tensile testing, dielectric measurements, and SEM/EDX analyses. The results demonstrate that TESPI surface modification promotes strong interfacial bonding and homogeneous filler dispersion within the cyanate ester matrix. An optimal balance between mechanical integrity and dielectric performance was achieved at 15 wt% total filler loading (K3), exhibiting a dielectric constant close to 10 and the lowest dielectric loss (tan δ ≈ 0.0047 at 1 MHz). Microstructural observations confirm that excessive filler loading leads to agglomeration and increased dielectric loss. Overall, the combined use of transparent glass and BaTiO₃ fillers, together with effective interfacial engineering, enables precise tuning of dielectric properties in cyanate ester composites for high-frequency electronic applications. Full article

The fabrication of sustainable packaging films based on chitosan/starch (CTS/Starch) blends, reinforced with Chitosan Nanoparticles (CNPs), was achieved via the casting blend technique. This research explored the impact of varying CNPs loading on critical physicochemical properties, including water vapor permeation (WVP), thermal stability, and mechanical strength. To elucidate the structural and chemical complexities of the blend films, surface morphology was investigated via Scanning Electron Microscopy (SEM), internal architecture was visualized using Transmission Electron Microscopy (TEM), and molecular interactions were probed through Fourier Transform Infrared (FTIR) spectroscopy. The reduction in WVP from 6.18 ± 0.54 to 5.38 ± 0.93 g.m⁻¹.s⁻¹.pa⁻¹, equilibrium moisture content (EMC) from 16.52 ± 1.03% to 12.5 ± 1.05%, and water absorbency (WA) from 340 ± 1.63% to 88.65 ± 1.12% in CTS/Starch blend films demonstrated loaded with (0–8 wt%) CNPs loading. Concurrently, films with 2–8 wt% CNP loading exhibited an increase in opacity from 2.38 ± 1.01 mm⁻¹ to 4.83 ± 0.83 mm⁻¹, accompanied by a decrease in transmittance from 89.20 ± 0.50% to 79.70 ± 1.20%. These findings collectively indicated that the CNP-incorporated chitosan/starch composites offer enhanced ultraviolet light shielding and improved water barrier capabilities compared to the non-reinforced chitosan/starch films, underscoring their promising utility in food and pharmaceutical packaging applications. Full article

Granitic soils in the Highlands support the cultivation of Arabica coffee in northern Thailand; however, their geochemical and radiological properties are inadequately defined. This study examined major oxides, trace elements, natural radionuclides, and extractable phosphorus in granitic-derived coffee soils from the Agricultural Innovation Research, Integration, Demonstration, and Training Center (AIRID) in Chiang Mai. Twenty soil samples were obtained from 10 locations at two depth intervals (0–30 cm and 30–60 cm). Major and trace elements were analyzed via X-ray fluorescence (XRF), natural radionuclides were analyzed through high-purity germanium (HPGe) gamma spectrometry, and extractable phosphorus was determined using the Bray II method. The soils demonstrate remarkably high ⁴⁰K activity concentrations (1.2–1.9 kBq kg⁻¹) and increased K₂O contents (4.9–7.8 wt%), about three to five times more than worldwide soil averages according to Reimann & de Caritat, indicating enrichment from potassium-rich granitic rocks. Major oxide compositions suggest extensive tropical weathering, characterized by elevated SiO₂ (>60 wt%) and Al₂O₃ (>14 wt%), alongside significant depletion of CaO and MgO (<1 wt%). In topsoil, Bray II–extractable phosphorus constitutes 10–25% of total phosphorus and has a robust positive connection with P₂O₅ (R² = 0.95, p < 0.001), signifying surface accumulation and restricted vertical mobility. Multivariate analysis indicates lithogenic grouping of trace elements with negligible vertical redistribution. These findings establish a geochemical and radiological baseline for highland coffee soils in northern Thailand, with implications for soil fertility assessment, soil–plant transfer research, and evaluations of natural radioactive exposure related to coffee production. Full article

Inorganic magnesium potassium phosphate (MKP) coatings offer rapid, zero-volatile organic compound (VOC) corrosion protection for steel structures. However, their application is impeded by insufficient mechanical strength and limited barrier durability. This study integrates calcium sulfate whiskers (CSWs) into a sprayable MKP matrix. Unlike conventional polymeric or metallic fibers, CSWs demonstrate excellent chemical compatibility with the MKP matrix, enabling a dual-enhancement mechanism. The optimal formulation, containing 15 wt.% CSWs, boosts the 28-day compressive strength by 35% and the bond strength by 39%. Electrochemical analysis shows a 93.6% increase in coating resistance (R_f), indicating an improved physical barrier against corrosive species, along with a 52% reduction in corrosion current density. These improvements result from fiber bridging and a dissolution–reprecipitation process that densifies the whisker–matrix interface. Nevertheless, an excessive amount of CSW (20 wt.%) disrupts the matrix continuity and reduces performance. This work presents a high-strength, zero-VOC, spray-applied coating with a novel dual-enhancement mechanism for durable steel protection in aggressive environments. Full article