Search Results (9,154)

This study explores the use of lignocellulosic Tectona grandis seeds (TGs), hydrochar (HC-230-4), and activated carbon (AC-850-5) produced via hydrothermal carbonization and followed by CO₂ activation for removing acridine yellow G (AYG) and acridine orange 14 (ABO) from water. HC-230-4 showed a rich presence of surface functional groups and irregular morphology with some sphere-like structures. In contrast, AC-850-5 exhibited a much higher surface area (729.7 m²/g), though with fewer surface functional groups than HC-230-4. The batch method was used to study the effects of contact time, pH, dye concentration, and temperature. Among the materials, AC-850-5 showed the highest adsorption capacity of 198 mg/g for AYG and 171 mg/g for ABO at 25 °C, around 12% higher than commercial activated carbon. The adsorption process was spontaneous and endothermic, fitting well to the Langmuir isotherm model, suggesting monolayer coverage. The adsorption kinetics followed the pseudo-second-order model, indicating that the rate depends on the surface site availability. Intraparticle diffusion analysis further confirmed a multi-step adsorption process. These findings show the strong potential of TG-derived activated carbon as an effective and sustainable material for removing acridine dyes from polluted water. Full article

JP-10 (exo-tetrahydrodicyclopentadiene) is a high-energy-density hydrocarbon broadly used in advanced aerospace propulsion as a regenerative cooling fluid; in this study, we aimed to clarify how fuel pressure affects its thermal degradation (oxidative and pyrolytic) in near-isothermal flowing reactor. Experiments were performed under oxidative conditions (wall temperature 623.15 K, p = 0.708–6.816 MPa) and pyrolytic conditions (wall temperature 793.15 K, p = 2.706–7.165 MPa); carbon deposits were quantified by LECO analysis, oxidation activity was assessed by temperature-programmed oxidation (TPO), and morphology was performed by FESEM and EDS. Results show that oxidative coking is minimal (5.37–14.95 μg·cm²) and largely insensitive to pressure in the liquid phase (1.882–6.816 MPa), whereas at 0.708 MPa (gas/phase-change conditions), deposition increases, implicating phase and local heat-transfer effects. Under oxidative conditions, deposits are predominantly amorphous carbon with a disordered structure, formed at relatively low temperatures, with only a few fiber-like metal sulfides identified by EDS. In contrast, under pyrolysis conditions, the deposits are predominantly carbon nanotubes, exhibiting well-defined tubular morphology formed at elevated temperatures via metal-catalyzed growth. The pyrolysis coking yield is substantially higher (66.88–221.89 μg·cm⁻²) and increases with pressure. The findings imply that the pressure influences the coking of JP-10 via phase state under oxidative conditions and residence time under pyrolytic conditions, while basic morphologies of coke deposits remain similar; operationally, maintaining the working pressure higher than the saturated vapor pressure can mitigate oxidation coking associated with phase transitions, and minimizing residence time can mitigate pyrolytic coking. Full article

Comprehending the effects of climate change on the range of endangered species is essential for formulating successful conservation strategies. This research examines two nationally protected dung beetle species (Heliocopris dominus and Heliocopris bucephalus) in China to forecast their probable habitat range under present and future climate scenarios. Employing MaxEnt modeling with validated occurrence records and environmental variables, we discerned critical factors affecting their distribution and anticipated changes in habitat suitability. Results reveal that isothermality, temperature seasonality, maximum temperature of the warmest month, and annual precipitation are the principal environmental drivers. Presently, appropriate habitats are primarily located in southern Yunnan and Hainan, with future forecasts indicating a northward extension into additional areas. These findings offer critical insights for choosing conservation zones for these vulnerable species amid shifting climate conditions. Full article

Nitrogen (N) and phosphorus (P) play vital roles in crop growth. However, conventional fertilizers exhibit low utilization efficiency, making them prone to causing resource wastage and water eutrophication. Although metal–organic frameworks (MOFs) have shown great potential for application in controlled-release fertilizers (CRFs), currently reported MOF-based CRFs suffer from low nutrient content, which limits their further application. To address this issue, this study synthesized a series of hierarchically porous MOFs, denoted as MIL-156(X), using sodium acetate as a modulator under hydrothermal conditions. These materials were subsequently loaded with urea and phosphate from aqueous solution to form MOFs-based CRFs (N-P-MIL-156(X)). Results indicate that MIL-156(X) retain microporous integrity while incorporating abundant mesopores. Increasing modulator content reduced particle size and average pore diameter but increased specific surface area and adsorption capacity for urea and phosphate. MIL-156-H (with a high modulator content addition) exhibited the highest adsorption capacity, conforming to Langmuir isotherm and pseudo-second-order kinetics. The adsorption mechanisms of urea and phosphate involved hydrogen bonding and the formation of Ca intra-spherical complexes, respectively. N-P-MIL-156-H contained 10.8% N and 16.3% P₂O₅, with sustained release durations exceeding 42 days (N) and 56 days (P₂O₅) in an aqueous solution. Pot trials demonstrated significantly higher nutrient use efficiency (N-44.8%, P₂O₅-16.56%) and a 12.22% yield increase compared to conventional fertilization (N-35.6%, P₂O₅-13.32%). Thus, N-P-MIL-156-H-based fertilization significantly promotes rice growth and N/P utilization efficiency, offering a promising strategy for developing controlled-release fertilizers and improving nutrient management. Full article

Phosphorus-based compounds play a crucial role in agricultural productivity. However, excessive phosphorus discharge into water bodies contributes to eutrophication. This study proposes a circular approach for phosphorus recovery and reuse through the thermal valorization of Posidonia oceanica residues, an abundant marine biomass along Mediterranean coasts. After energy recovery from this waste (12.3 MJ kg⁻¹), the resulting ash was assessed as an effective adsorbent for aqueous phosphorus removal. Batch experiments were conducted to evaluate adsorption kinetics and equilibrium, considering the influence of key operational variables, such as temperature, pH, and adsorbent dosage. Under optimal conditions, the material achieved a maximum retention of approximately 55–60 mgP g⁻¹. The Freundlich model successfully describes the equilibrium isotherm data, indicating a heterogeneous adsorbent and an overall endothermic process. Phosphorus removal was favored at basic pH values (9.5–10.5), where the monohydrogen phosphate predominates. Leaching tests further revealed that saturated material releases phosphorus and other minerals in a manner clearly dependent on the final pH, with higher phosphorus release under more acidic conditions. These results suggest that Posidonia ash could serve as a low-cost adsorbent while also acting as a potential phosphorus source in soils. Full article

As the production of electric vehicles grows, the rare earth elements Pr and Nd become increasingly significant, as they are key in magnetic materials production. In order to achieve the green and efficient recovery of Pr and Nd from the rare earth leachate, this paper selected kaolinite and halloysite as adsorbents to conduct rare earth solution adsorption experiments for exploring the effects of the initial leachate concentration, the solution pH, and the adsorption temperature on the adsorption process. The adsorption characteristics of Pr and Nd by clay minerals were analyzed by quantum chemical calculation. The results showed that the adsorption effects of clay minerals on Pr and Nd decreased with the rise of leachate concentration. When leachate pH increased, the adsorption efficiency of kaolinite and halloysite for Pr firstly increased and then decreased, and the optimal adsorption efficiency was 13.33% and 24.778% at pH 6, respectively. The adsorption effects of kaolinite and halloysite on Nd enhanced gradually with the increase in pH, which increased to 15.925% and 30.482% at pH 7, respectively. With temperature increased, the adsorption of Pr and Nd by kaolinite and halloysite was positively correlated. The isothermal adsorption model was fitted to the experimental data, and it was found that the adsorption of Pr and Nd by kaolinite and halloysite was consistent with the Langmuir model, with R² above 0.96, indicating that the adsorption process was a single molecular layer adsorption. The results provide theoretical support for the effective recycling of Pr and Nd, which is of great significance for the utilization of rare earth resources in permanent magnets. Full article

The acceleration of climate change and increasing weather-related disasters require more active utilization of renewable energy. To maximize the use of renewable energy, energy storage is an essential part. Liquid piston gas compressors have recently drawn attention because of their applicability to compressed air-based energy storage. Aqueous foam can be used to enhance the efficiency of liquid piston gas compression by boosting heat transfer. To validate the effectiveness of the combination of liquid piston and aqueous foam in a multi-stage compression system, which can contribute to higher efficiency, the present work performed experimental study at various pressure levels. Compressions were performed with and without aqueous foam at three different initial pressure levels of 1, 2, and 3 bars. For each cycle of compression, a pressure ratio of 2 was used, and the impact of pressure levels on compression efficiency was measured. With the use of foam, isothermal efficiencies of 91.4, 88.2, and 86.6% were observed at 1, 2, and 3 bar(s), which improved by 2.2, 2.1, and 1.3% compared to the baseline compressions. To identify the cause of the effectiveness variations, the volume changes in the foam at the different pressure levels were visually compared. In higher-pressure tests, a significant reduction in the foam amount was observed, and this change may contribute to the decreased effectiveness of the technique. Full article

For the first time, the kinetics of isothermal curing and thermal degradation of polyethylene glycol maleate (pEGM)–based systems and their composites with mineral fillers were investigated in the presence of a benzoyl peroxide/N,N-Dimethylaniline redox-initiating system. DSC analysis revealed that the curing process at 20 °C can be described by the modified Kamal autocatalytic model; the critical degree of conversion (α_c) decreases with increasing content of the unsaturated polyester pEGM and in the presence of fillers. In particular, for unfilled systems, α_c was 0.77 for pEGM45 and 0.60 for pEGM60. TGA results demonstrated that higher pEGM content and the incorporation of fillers lead to increased thermal stability and residual mass, along with a reduction in the maximum decomposition rate (dTGₘₐₓ). Calculations using the Kissinger–Akahira–Sunose and Friedman methods also confirmed an increase in the activation energy of thermal degradation (E_a): E_KAS was 419 kJ/mol for pEGM45 and 470 kJ/mol for pEGM60, with the highest values observed for pEGM60 systems with fillers (496 kJ/mol for SiO₂ and 514 kJ/mol for CaCO₃). Rheological studies employing three-interval thixotropy tests revealed the onset of thixotropic behavior upon filler addition and an increase in structure recovery after deformation of up to 56%. These findings underscore the potential of pEGM-based systems for low-temperature curing and for the design of composite materials with improved thermal resistance. Full article

The use of additive manufacturing (AM) has seen increased utilization over the last decade, thanks to well-documented advantages such as lower startup costs, reduced wastage, and the ability to rapidly prototype. The poor surface finish of unprocessed AM components is one of the major drawbacks of this technology, with the research literature suggesting a measurable impact on flow characteristics and burner operability. For instance, surface roughness has been shown to potentially increase resistance to boundary layer flashback—an area of high concern, particularly when utilizing fuels with high hydrogen content. A more detailed understanding of the underlying thermophysical mechanisms is, therefore, required. Computational fluid dynamics can help elucidate the impact of these roughness effects by enabling detailed data interrogation in locations not easily accessible experimentally. In this study, roughness effects on a generic gas turbine swirler were numerically modeled using a low-y+ detached eddy simulation (DES) approach. Three DES models were investigated utilizing a smooth reference case and two rough cases, the latter employing a literature-based and novel equivalent sand-grain roughness (k_s) correlation developed for this work. Existing experimental isothermal and CH₄ data were used to validate the numerical simulations. Detailed investigations into the effects of roughness on flow characteristics, such as swirl number and recirculation zone position, were subsequently performed. The results show that literature-based k_s correlations are unsuitable for the current application. The novel correlation yields more promising outcomes, though its effectiveness depends on the chosen turbulence model. Moreover, it was demonstrated that, for identical k_s values, while trends remained consistent, the extent to which they manifested differed under reacting and isothermal conditions. Full article

Thermal barrier coatings (TBCs) extend gas-turbine blade lifetime by improving high-temperature oxidation resistance and mechanical performance. We investigated the microstructural evolution, TGO growth, and Al depletion in air-plasma-sprayed (APS) single-layer YSZ top coat over a NiCrCoAlY bond coat on Ni-based superalloy circular plates, heat treated isothermally at 850 °C and 1000 °C for 50–5000 h. Cross-sectional SEM/EDS analysis showed TGO quadratic thickening kinetics at both temperatures, reaching ~10 µm at 1000 °C/5000 h, the growth rate of which was ~5.8 times higher than at 850 °C. On top of the single-layer TGO of Al₂O₃ observed from the onset, a NiCrCo oxide layer appeared and grew from ≥500 h at 850 °C, with increasing growth rate and cracking. The layer configuration of the YSZ top coat, the TGO of Al₂O₃, and the bond coat (comprising β-NiAl and γ-NiCr) on top of GTD111, showed an Al concentration gradient in the bond coat starting at 850 °C for 250 h, which intensified with increased duration and temperature. The decrease in Al concentration in the bond coat and the growth of TGO are due to the dissolution of β-NiAl and subsequent Al diffusion to the Al₂O₃ TGO. Full article

Vincristine is a classical chemotherapeutic agent widely used for its ability to disrupt microtubule polymerization, yet additional molecular effects may contribute to its anticancer activity. G-quadruplexes (G4s), non-canonical nucleic acid structures enriched in regulatory regions of the genome and in mitochondrial DNA, have emerged as relevant modulators of cellular homeostasis. In this study, we investigated whether vincristine can influence G4 biology. Cancer cells treated with vincristine were analyzed by immunofluorescence, revealing a consistent increase in nuclear and mitochondrial G4 foci. In particular, mitochondrial G4s were significantly elevated by approximately 1.5–2.5 fold compared to untreated cells, an effect accompanied by a detectable reduction in membrane potential, indicative of impaired organelle function. In addition, biophysical analyses on representative G4-forming sequences were carried out. Proton nuclear magnetic resonance titrations showed localized chemical shift perturbations upon vincristine addition, circular dichroism confirmed preservation of G4 topology, and isothermal titration calorimetry indicated weak but enthalpically favorable interactions. Taken together, these results suggest that vincristine perturbs both the cellular G4 landscape and mitochondrial homeostasis, while also engaging G4 DNA in vitro. Although additional studies are required to establish the mechanistic details, this work provides proof-of-concept for a previously unrecognized dimension of vincristine’s anticancer action. Full article

Isothermal hot compression tests were performed on an Al-4.8Cu-0.25Mg-0.32Mn-0.17Si alloy using a Gleeble-3500 thermomechanical simulator within the temperature range of 350–510 °C and strain rate range of 0.001–10 s⁻¹, achieving a true strain of 0.9. The constitutive equation and hot processing maps were established to predict the flow behavior of the alloy. The hot deformation mechanisms were investigated through microstructural characterization using inverse pole figure (IPF), grain boundary (GB), and grain orientation spread (GOS) analysis. The results demonstrate that both dynamic recovery (DRV) and dynamic recrystallization (DRX) occur during hot deformation. At high lnZ values (high strain rates and low deformation temperatures), discontinuous dynamic recrystallization (DDRX) dominates. Under middle lnZ conditions (low strain rate or high deformation temperature), both continuous dynamic recrystallization (CDRX) and DDRX are the primary mechanisms. Conversely, at low lnZ values (low strain rates and high temperatures), CDRX and geometric dynamic recrystallization (GDRX) become predominant. The DRX process in the Al-Cu-Mg alloy is controlled by the deformation temperature and strain rate. Full article

Liquid biopsies promise major advantages for cancer screening and diagnosis. By detecting biomarkers in peripheral blood samples, liquid biopsies reduce the need for invasive techniques and provide important genetic information integral to the emerging molecular classification of cancers. Unfortunately, the concentrations of most biomarkers, particularly circulating tumour nucleic acids, are vanishingly small—beyond the sensitivity and specificity of most assays. Clustered Regularly Interspaced Short Palindromic Repeats diagnostics (herein labelled ‘CRISPR-Dx’) use gene editing tools to detect, rather than modify, nucleic acids with extremely high specificity. These tools are commonly combined with isothermal nucleic acid amplification to also achieve sensitivities comparable to high-performance laboratory-based techniques, such as digital PCR. CRISPR assays, however, are inherently well suited to adaptation for point-of-care (POC) use, and unlike antigen-based POC assays, are significantly easier and faster to develop. In this review, we summarise current CRISPR-Dx platforms and their analytical potential for cancer biomarker discovery, with an emphasis on enhancing early diagnosis, disease monitoring, point-of-care testing, and supporting cancer therapy. Full article

This study investigates the hydrogen adsorption performance of activated carbon (AC) derived from rice husks and modified with magnesium and nickel salts. Adsorption isotherms were recorded at 25 °C and 50 °C up to 80 bar, simulating practical storage conditions. The unmodified AC exhibited the highest hydrogen uptake (0.62 wt% at 25 °C), attributed to its high surface area and dominant ultramicroporosity (<0.9 nm). Modifications with Mg and Ni reduced adsorption capacity, likely due to partial pore blockage and decreased surface functionality, as confirmed by FTIR, Raman, and XRD analyses. Despite this, all samples demonstrated stable cyclic adsorption–desorption behavior and consistent isotherm profiles. Hysteresis observed in the modified samples suggests capillary condensation within mesopores. Thermodynamic analysis confirmed the exothermic nature of hydrogen adsorption. Among the modified materials, ACM10 (Mg-modified) exhibited the best performance (0.54 wt%), highlighting the importance of optimizing the metal content. The obtained results indicate that the micropore size distribution and accessible surface functionality critically govern the hydrogen storage capacity, suggesting that unmodified AC is a promising candidate for low-temperature hydrogen storage systems. Full article

As a clean and renewable energy source with huge reserves, hot dry rock geothermal resources have received wide attention. The geothermal field plays a crucial role in studying the heat source mechanism of hot dry rock, defining target areas, and evaluating resources. In this study, the three-dimensional structural inversion of the Gonghe Basin is carried out using magnetotelluric sounding, and the Curie isothermal surface is obtained by analyzing regional aeromagnetic data. By coupling low-resistance and high-conductivity zones with temperature distribution and integrating the Curie isothermal surface with high-temperature anomalies of some melts, we constructed an initial temperature field model based on comprehensive geophysical data. The temperature field model of the Gonghe Basin is established by using the adaptive finite-element temperature conduction control equation and the constraints of the temperature data from geothermal wells. The temperature field model provides a basis for the future exploration of hot dry rock resources in the Gonghe area. Full article