Search Results (206)

This study presents a comprehensive computational analysis of flow rate efficiency during uranium extraction via the In Situ Recovery method. Using field data from a deposit located in Southern Kazakhstan, a series of mathematical models were developed to evaluate the distribution and balance of leaching solution. A reactive transport model incorporating uranium dissolution kinetics and acid–rock interactions were utilized to assess the accuracy of both traditional and proposed methods. The results reveal a significant spatial imbalance in sulfuric acid distribution, with up to 239.1 tons of acid migrating beyond the block boundaries. To reduce computational demands while maintaining predictive accuracy, two alternative methods, a streamline-based and a trajectory-based approach were proposed and verified. The streamline method showed close agreement with reactive transport modeling and was able to effectively identify the presence of intra-block reagent imbalance. The trajectory-based method provided detailed insight into flow dynamics but tended to overestimate acid overflow outside the block. Both alternative methods outperformed the conventional approach in terms of accuracy by accounting for geological heterogeneity and well spacing. The proposed methods have significantly lower computational costs, as they do not require solving complex systems of partial differential equations involved in reactive transport simulations. The proposed approaches can be used to analyze the efficiency of mineral In Situ Recovery at both the design and operational stages, as well as to determine optimal production regimes for reducing economic expenditures in a timely manner. Full article

Directed Energy Deposition is an additive manufacturing subgroup that uses a laser beam to melt the wire or powder to create a melt pool. In the current study, a scientometric analysis has been carried out to analyze the contribution of countries, publication type analysis, distribution of publications over the years, keywords analysis, author analysis, cited journal, categories, institutes of publication, and report the practical implications. Firstly, the database was extracted from the Web of Science and then post-processed with CiteSpace 6.2.R4 and VOSviewer 1.6.20 software. Afterward, the associated results had been extracted and reported. It was found that China is the leader according to publication, followed by the USA and Germany, which mostly published their achievements in article and proceeding paper formats, which are increasing annually. According to the keywords, additive manufacturing, Laser Metal Deposition, and fabrication are the most commonly used. Based on the CiteSapce and VOSviewer results, Lin, Xin and Huang, Weidong are the authors with the highest publication rates. In addition, Additive Manufacturing, Materials & Design, and Materials Science and Engineering: A are the most cited journals, and regarding the categories, materials science, multidisciplinary, applied physics, and manufacturing engineering are the most commonly used DED processes. Northwestern Polytechnical University, Fraunhofer Gesellschaft, and the United States Department of Energy (DOE) have performed the most research in the field of DED. Full article

In wind-assisted orchard spraying operations, the dynamic response of leaves—manifested through changes in their posture—critically influences droplet deposition on both sides of the leaf surface and the penetration depth into the canopy. These factors are pivotal in determining spray coverage and the spatial distribution of pesticide efficacy. However, current research lacks comprehensive quantification and correlation analysis of the temporal response characteristics of leaves under wind disturbances. To address this gap, a systematic analytical framework was proposed, integrating real-time leaf segmentation and tracking, geometric feature quantification, and statistical correlation modeling. High-frame-rate videos of fluttering leaves were acquired under controlled wind conditions, and background segmentation was performed using principal component analysis (PCA) followed by clustering in the reduced feature space. A fine-tuned Segment Anything Model 2 (SAM2-FT) was employed to extract dynamic leaf masks and enable frame-by-frame tracking. Based on the extracted masks, time series of leaf area and inclination angle were constructed. Subsequently, regression analysis, cross-correlation functions, and Granger causality tests were applied to investigate cooperative responses and potential driving relationships among leaves. Results showed that the SAM2-FT model significantly outperformed the YOLO series in segmentation accuracy, achieving a precision of 98.7% and recall of 97.48%. Leaf area exhibited strong linear coupling and directional causality, while angular responses showed weaker correlations but demonstrated localized synchronization. This study offers a methodological foundation for quantifying temporal dynamics in wind–leaf systems and provides theoretical insights for the adaptive control and optimization of intelligent spraying strategies. Full article

Antibiotic resistance is one of the most significant public health issues today. As a consequence, there is an urgent need for novel classes of antibiotics. This necessitates the development of highly efficient screening methods for the rapid identification of antibiotic-producing bacteria. Here, we describe a new method for high-throughput screening of antimicrobial compounds (AMC) producing halophilic bacteria. Our methodology used a newly designed 3D-printed Petri plate replicator used for drop deposition and colony replication. We employed this device in combination with a modified agar overlay assay to screen more than 7400 bacterial colonies. A total of 54 potential AMC producers were discovered at a success rate of 0.7%. Although 40% of them lost their antibacterial activity during the secondary screening, 22 strains retained inhibitory activity and were able to suppress the growth of one or more safe relatives of the ESKAPE group pathogens. The ethyl acetate extract from the most potent strain, Virgibacillus salarius POTR191, demonstrated moderate antibacterial activity against Enterococcus faecalis, Acinetobacter baumanii, and Staphylococcus epidermidis with minimal inhibitory concentrations of 128 μg/mL, 128 μg/mL, and 512 μg/mL, respectively. We propose that our replica plate assay could be used for target-based antimicrobial screening of various extremophilic bacteria. Full article

The coastline of the Yellow River Delta in China has experienced significant dynamic changes due to both natural and human activities. Investigating its coastal dynamics and understanding the equilibrium with riverine runoff and sediment discharge is crucial for ecological balance and sustainable development in the region. In this study, a coastline extraction algorithm was developed by integrating water index and dynamic frequency thresholds based on the Google Earth Engine platform. Long-term optical remote sensing datasets from Landsat (1988–2016) and Sentinel-2 (2017–2023) were utilized. The End Point Rate (EPR) and Linear Regression Rate (LRR) methods were employed to quantify coastline changes, and the relationship between coastal evolution and runoff–sediment dynamics was investigated. The results revealed the following: (1) The coastline of the Yellow River Delta exhibits pronounced spatiotemporal variability. From 1988 to 2023, the Diaokou estuary recorded the lowest EPR and LRR values (−206.05 m/a and −248.33 m/a, respectively), whereas the Beicha estuary recorded the highest values (317.54 m/a and 374.14 m/a, respectively). (2) The cumulative land area change displayed a fluctuating pattern, characterized by a general trend of increase–decrease–increase, indicating a gradual progression toward dynamic equilibrium. The Diaokou estuary has been predominantly erosional, while the Qingshuigou estuary experienced deposition prior to 1996, followed by subsequent erosion. In contrast, the land area of the Beicha estuary has continued to increase since 1997. (3) Deltaic progradation has been primarily governed by runoff–sediment dynamics. Coastline advancement has occurred along active river channels as a result of sediment deposition, whereas former river mouths have retreated landward due to insufficient fluvial sediment input. In the Beicha estuary, increased land area has exhibited a strong positive correlation with annual sedimentary influx. The critical sediment discharge required to maintain equilibrium has been estimated at 79 million t/a for the Beicha estuary and 107 million t/a for the entire deltaic region. These findings provide a scientific foundation for sustainable sediment management, coastal restoration, and integrated land–water planning. This study supports sustainable coastal management, informs policymaking, and enhances ecosystem resilience. Full article

Urbanization, escalating agriculture, tourism, and industrial development in the Chiang Mai–Lamphun groundwater basin in northern Thailand have increased water demand, causing widespread groundwater extraction. Over the past few decades, there has been a rapid, unrecoverable steady drop in groundwater levels in several areas in Chiang Mai and Lamphun provinces. This study employed hydrogeological investigations, hydrometeorological data analyses, stable isotopic analysis (δ¹⁸O and δ²H), and groundwater flow modeling using a 3D groundwater flow model (MODFLOW) to quantify groundwater recharge and delineate important groundwater recharge zones within the basin. The results showed that floodplain deposits exhibited the highest recharge rate, 104.4 mm/y, due to their proximity to rivers and high infiltration capacity. In contrast, younger terrain deposits, covering the largest area of 1314 km², contributed the most to total recharge volume with an average recharge rate of 99.8 mm/y. Seven significant recharge zones within the basin, where annual recharge rates exceeded 105 mm/y (average recharge of the entire basin), were also delineated. Zone 4, covering parts of densely populated Muaeng Lamphun, Ban Thi, and Saraphi districts, had the largest area of 330 km² and a recharge rate of 130.2 mm/y. Zone 6, encompassing Wiang Nong Long, Bai Hong, and Pa Sang districts, exhibited the highest recharge rate of 134.6 mm/y but covered a smaller area of 67 km². Stable isotopic data verified that recent precipitation predominantly recharged shallow groundwater, with minimal evaporation or isotopic exchange. The basin-wide average recharge rate was 104 mm/y, reflecting the combined influence of geology, permeability, and spatial distribution. These findings provide critical insights for sustainable groundwater management in the region, particularly in the context of climate change and increasing water demand. Full article

Fusarium verticillioides is one of the pathogenic fungi causing maize ear rot, and its secreted fumonisins accumulated in plants pose significant threats to human health. To reduce the incidence of maize ear rot and fumonisin contamination, this study isolated numerous endophytic fungi from maize plants. Through inhibition zone and dual culture assays, an endophytic fungal strain, FJ284, demonstrating notable antifungal activity against F. verticillioides was screened. 18S rDNA gene sequencing was employed for fungal identification, and the sequences were deposited in NCBI GenBank. FJ284 was identified as Penicillium oxalicum. The ethyl acetate extract of P. oxalicum was analyzed using gas chromatography–mass spectrometry (GC-MS), revealing 52 compounds, including several secondary metabolites with documented anticancer, antimicrobial, and antioxidant activities. Furthermore, a spectroscopic method was developed to assess the inhibitory effect of strain FJ284 against F. verticillioides, showing maximum inhibition at 48 h. Finally, Ultra-High-Performance Liquid Chromatography–Mass Spectrometry (UHPLC-MS) analyses confirmed that FJ284 significantly inhibited three fumonisins (suppression rates > 50%), with efficacy ranked as fumonisin B3 (FB3) > fumonisin B2 (FB2) > fumonisin B1 (FB1). Full article

This study investigated the impact of the nanocrystalline atomic layer-deposited hydroxyapatite (ALD-HA) coating of titanium (Ti) surface on the attachment and proliferation of human gingival fibroblasts (HGFs). Ti discs were divided into ALD-HA-coated and non-coated (NC) controls. HGFs were harvested from gingival biopsies of patients subjected to extraction of their third molar. The cells were cultivated on the Ti discs for 2 and 24 h to evaluate the initial cell attachment using confocal microscopy. Spreading of cells and the signals of focal adhesion proteins were measured. Moreover, the adhesion proteins vinculin and paxillin expression levels were evaluated using Western blot after 3 d of cultivation. In addition, the proliferation of HGF was assessed by cultivating the cells on Ti discs for 1, 3, and 7 d. Fibroblast spreading was significantly greater on ALD-HA surfaces than on NC surfaces after 2 h (p < 0.001). In addition, the signals of vinculin and paxillin were significantly higher on the ALD-HA than on the NC surfaces at 2 and 24 h. The confocal microscope analysis also revealed significantly higher expression of focal adhesion molecules on ALD-HA surfaces at both time points. Furthermore, the cell proliferation rate was significantly higher at d 3 (p = 0.022) and d 7 (p < 0.001) on the ALD-HA compared to the NC surfaces. These findings indicate that ALD-HA coating enhances focal adhesion formation, cell spreading, and proliferation on Ti surfaces, suggesting its potential to improve gingival tissue attachment to Ti implant surfaces. Full article

Natural rubber skim latex is commonly discarded as waste or turned into skim natural rubber products such as skim crepe and skim blocks. It is challenging to retrieve all residual rubbers in skim latex since it has a very low rubber content and many non-rubber components like protein. Manufacturers conventionally utilize concentrated sulfuric acid as a coagulant. This method generates many effluents and hazardous pollutants that negatively impact the environment. This work presents an innovative method for enhancing the skim latex’s value by employing an ultrafiltration membrane. This study aims to establish a hydrophilic PVDF-TiO₂ mixed-matrix membrane. The skim latex was processed through a membrane-based ultrafiltration process, which yielded two products: skim latex concentrate and skim serum. Skim latex deposits that cause fouling on the membrane surface can be identified by SEM-EDX and FTIR analysis. The PVDF–PVP-TiO₂ mixed-matrix membrane generated the maximum skim serum flux of 12.72 L/m²h in contrast to the PVDF pure membranes, which showed a lower flux of 8.14 L/m²h. CHNS analysis shows that a greater amount of nitrogen, which is indicative of the protein composition, was successfully extracted by the membrane separation process. These particles may adhere to the membrane surface during filtration, obstructing or decreasing the number of fluid flow channels. The deposition reduces the effective size of membrane pores, leading to a decline in flux rate. The hydrophilic PVDF-TiO₂ mixed-matrix membrane developed in this study shows strong potential for application in the latex industry, specifically for treating natural rubber skim latex, a challenging by-product known for its high fouling potential. This innovative ultrafiltration approach offers a promising method to enhance the value of skim latex by enabling more efficient separation and recovery. Full article

Background/Objectives: Cirsium setosum (commonly known as thistle) is a traditional Chinese medicinal plant with significant therapeutic potential, exhibiting hemostatic, antioxidant, and wound-healing properties. Electrospinning offers a versatile platform for fabricating nanoscale scaffolds with tunable functionality, making them ideal for drug delivery and tissue engineering. Methods: In this study, a bioactive extract from thistle was obtained and incorporated into a thermosensitive triblock copolymer (PNNS) and polycaprolactone (PCL) to develop a multifunctional nanofibrous scaffold for enhanced wound healing. The prepared nanofibers were thoroughly characterized using Fourier-transform infrared spectroscopy (FTIR), contact angle measurements, thermogravimetric analysis (TGA), and tensile fracture testing to assess their physicochemical properties. Results: Notably, the inclusion of PNNS imparted temperature-responsive behavior to the scaffold, enabling controlled deformation in response to thermal stimuli—a feature that may facilitate wound contraction and improve scar remodeling. Specifically, the scaffold demonstrated rapid shrinkage at a physiological temperature (38 °C) within minutes while maintaining structural integrity at ambient conditions (20 °C). In vitro studies confirmed the thistle extract’s potent antioxidant activity, while in vivo experiments revealed their effective hemostatic performance in a liver bleeding model when delivered via the composite nanofibers. Thistle extract and skin temperature-responsive contraction reduced the inflammatory outbreak at the wound site and promoted collagen deposition, resulting in an ideal wound-healing rate of above 95% within 14 days. Conclusions: The integrated strategy that combines mechanical signals, natural extracts, and electrospinning nanotechnology offers a feasible design approach and significant technological advantages with enhanced therapeutic efficacy. Full article

The optimal parameters for the microwave-assisted extraction of Epimedium brevicornum Maxim. were determined by using response surface methodology (RSM), increasing the extraction of flavonoids by 1.79 times. The resulting extract facilitated the green synthesis of zinc oxide nanoparticles (ZnONPs) with a wurtzite structure through a reaction with zinc nitrate. These ZnONPs were then incorporated into polycaprolactone (PCL) by using an electrospinning technique to produce nanofibers. The incorporation of ZnONPs resulted in an increase in Young’s modulus, biodegradation rate, and swelling ratio while decreasing the diameter and water contact angle of the nanofibers, thereby improving the hydrophilicity of PCL. ZnO demonstrates excellent biocompatibility with periodontal ligament stem cells (PDLSCs), increasing cell proliferation and enhancing alkaline phosphatase activity by 56.9% (p < 0.05). Additionally, mineralization deposition increased by 119% (p < 0.01) in the presence of 1% ZnO and showed a concentration-dependent response. After inducing PDLSC cultures with PCL–1% ZnO for 21 days, the protein expression levels of Runx2 and OCN increased by 50% (p < 0.05) and 30% (p < 0.001), respectively. Additionally, Col-1, Runx2, BSP, and OCN gene expression levels increased by 2.18, 1.88, 1.8, and 1.7 times, respectively. This study confirms that biosynthesized ZnONPs improve the physical properties of PCL nanofibers and effectively induce the osteogenic differentiation of PDLSCs. Full article

The mechanical properties of metals produced by Wire Arc Additive Manufacturing (WAAM) differ significantly from those of rolled sheets due to their cast-like structure and repeated thermal cycling. This study aims to develop a predictive model capable of accurately estimating the stress–strain behavior of deposited metal based on process parameters. To achieve this, a series of experiments were conducted, and test specimens were produced. Arc current and deposition rate were selected as factors in a quasi-D-optimal experimental design. Tensile test data were analyzed using the least squares method, resulting in the derivation of regression equations that relate the stress–strain characteristics to the deposition parameters. To verify that the location of specimen extraction does not influence the test results, both thermal modeling and metallographic analysis were employed. Three key findings were established: (1) Thermal simulations and metallographic observations indicate that after the deposition of the first 5–6 layers, the microstructure becomes relatively similar; (2) significant microstructural variation occurs only in the final layer; and (3) six new regression equations were developed to predict the mechanical properties of the deposited metal based on WAAM process parameters. Full article

In the field of degradable metals, Zn-based implants have gradually gained more attention. However, the relatively slow degradation rate compared with the healing rate of the damaged bone tissue, along with the excessive Zn²⁺ release during the degradation process, limit the application of Zn-based implants. The use of intermetallic compounds with more negative electrode potentials as sacrificial anodes of Zn-based implants is likely to be a feasible approach to resolve this contradiction. In this work, three intermetallic compounds, MgZn₂, CaZn₁₃, and Ca₂Mg₆Zn₃, were prepared. The phase structures, microstructures, and relevant properties, such as thermal stability, in vitro degradation properties, and cytotoxicity of the compounds, were investigated. The XRD patterns indicate that the MgZn₂ and CaZn₁₃ specimens contain single-phase MgZn₂ and CaZn₁₃, respectively, while the Ca₂Mg₆Zn₃ specimen contains Mg₂Ca and Ca₂Mg₆Zn₃ phases. After purifying treatment in 0.9% NaCl solution, high purity Ca₂Mg₆Zn₃ phase was obtained. Thermal stability tests suggest that the MgZn₂ and CaZn₁₃ specimens possess good thermal stability below 773 K. However, the Ca₂Mg₆Zn₃ specimen melted at around 739.1 K. Polarization curve tests show that the corrosion potentials of MgZn₂, CaZn₁₃, and Ca₂Mg₆Zn₃ in simulated body fluid (SBF) were −1.063 V_SCE, −1.289 V_SCE, and −1.432 V_SCE, which were all more negative than that of the pure Zn specimen (−1.003 V_SCE). Clearly, these compounds can act as sacrificial anodes in Zn-based implants. The immersion tests indicate that these compounds were degraded according to the atomic ratio of the elements in each compound. Besides that, the compounds can efficiently induce Ca-P deposition in SBF. Cytotoxicity tests demonstrate that the 10% extracts prepared from these compounds exhibit good cell activity on MC3T3-E1 cells. Full article

Germanium, a critical material for advanced technologies, is enriched in certain coal deposits and by-products, including coal combustion and gasification fly ashes. This review examines germanium concentrations and occurrence modes in coal, coal gangue, and their combustion or gasification by-products, as well as hydrometallurgical recovery methods at laboratory, pilot, and industrial scales. Fly ashes from both coal combustion and gasification are particularly promising due to their higher germanium content and recovery rates, which can exceed 90% under optimal conditions. However, the low germanium concentrations and high levels of impurities in the leachates pose challenges, necessitating the development of innovative and selective separation techniques, primarily involving solvent extraction, ion exchange, or adsorption. Full article

Zirconium sulfide nanoparticles (Zr_xS_y) are prepared on a flexible substrate of carbon cloth (CC) via a one-step synthesis approach using the low-pressure chemical vapor deposition (LPCVD) technique. The scanning electron microscopy (SEM) image reveals that the particle sizes are in the range of ca. 3~23 nm with an average value of ~13.02 nm. The synthesized Zr_xS_y nanoparticles are composed of ZrS₃ and Zr₉S₂ phases, which is verified by X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HR-TEM). By using the Zr_xS_y/CC as a supercapacitor flexible electrode, the capacitance extracted from the cyclic voltammetry measurement is 406 C g⁻¹ at a scan rate of 5 mV s⁻¹; the capacitance values obtained from GCD curves at a current density of 0.5 A g⁻¹ and 1 A g⁻¹ are 151 and 134 C g⁻¹, respectively. These results highlight the promising potential of Zr_xS_y as a supercapacitor material for future energy-storage technology. Full article