Search Results (32,463)

Gas extraction is the main method to reduce the gas content of a coal seam and prevent coal and gas outburst. The sealing depth is one of the key parameters affecting the sealing effect. The principle of the high-density direct current method is to lay electrodes underground, and by injecting a stable DC current into the underground medium, the potential difference is measured to calculate the apparent resistivity, which reflects the difference in electrical conductivity of the underground rock or coal body, and then inferring the physical characteristics, such as its structure, water content, or stress state. Based on the basic principle of the high-density direct current method, this study analyzed the change rule of resistivity after the secondary stress of the roadway; tested the distribution of the roadway stress field in Juji Mine; and finally, determined the sealing depth of this coal seam. The main conclusions were as follows: The resistivity of the loose crushing zone after the roadway disturbance stress corresponded to the plasticity and destruction stage of the coal body, and the resistivity was larger compared with that of the original rock stress area. The stress concentration zone corresponded to the compression stage, where the destruction of the coal and rock state was smaller, and the resistivity was smaller compared with that of the original rock stress area. The range of the loose circle of the roadway of the coal seam was 6 m, and the range of the stress concentration zone was 6–17.5 m. The range of resistivity changes of the loose crushing zone was larger, and it had a large range of resistance, which had a good effect. The resistivity of the loose broken zone varied widely and was random, while the visual resistivity of the stress concentration zone was basically the same and was stable. Full article

In the pursuit of advancing the knowledge of energetic materials, we successfully formulated the energetic perovskite DAI-X1 with the chemical formula (C₁₂H₅₀I₆N₃Na₂O₃₆). Energetic perovskites hold great promise in various applications, including high-energy storage and propulsion systems, due to their unique combination of high energy density and structural versatility. DAI-X1, in particular, has attracted our attention because of its potential for optimized performance in these areas. We conducted an in-depth investigation into the high-pressure stability of DAI-X1 using in situ high-pressure Raman spectroscopy analysis. DAI-X1 possesses a cubic ABX₃ perovskite structure, and notable modifications in its Raman spectroscopic characteristics were noted within the pressure interval of 2.5–7.8 GPa, indicating structural instability under high pressure and suggesting a possible phase transition. Upon pressure release following compression to 12.5 GPa, the Raman spectra exhibit partial reversibility of the phase transition, as certain characteristic peaks return to their original positions while others retain irreversible shifts. This study establishes fundamental understanding for investigating high-pressure responses in DAI-X1 and analogous energetic materials. Full article

Background/Objectives: Hypercholesterolemia, accompanied by vascular inflammation, leads to the premature initiation and progression of atherosclerosis, and both are considered nowadays as well-established cardiovascular (CV) risk factors. For several years, proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9is), drugs that reduce the degradation of the receptors for low-density lipoprotein cholesterol (LDLRs), have appeared to be a very efficient lipid-lowering therapy among patients with complications resulting from atherosclerotic cardiovascular disease (ASCVD). Previous studies showed that drugs used to fight hypercholesterolemia (predominantly statins) have significant pleiotropic effects, including anti-inflammatory effects. To date, data on the potential impact of PCSK9 inhibitors, especially inclisiran, on the course of inflammation is still lacking. Therefore, we conceived a study to evaluate the effects of inclisiran on the markers of subclinical inflammation (e.g., pentraxin 3 (PTX3), interleukin-18 (IL-18), and soluble cluster of differentiation 40 ligand (CD40L)) and compared their magnitude in patients at high CV risk, with and without established heterozygous familial hypercholesterolemia (HeFH). Methods: A total of 24 patients at high cardiovascular risk, according to European Society of Cardiology (ESC) guidelines, with or without concomitant HeFH diagnosed using Dutch Lipid Clinic Network (DLCN) criteria, were enrolled in this study. Lipid concentrations and levels of subclinical inflammatory markers of atherosclerosis were measured at the beginning and after 3 months of therapy. Results: After three months of therapy with inclisiran, a statistically significant reduction included total cholesterol (TC): study group 1: from 287.6 ± 94.15 to 215.2 ± 89.08 [mg/dL], p = 0.022 and study group 2: from 211.71 ± 52.72 to 147.64 ± 55.44 [mg/dL], p < 0.001, and low-density lipoprotein cholesterol (LDL-c): study group 1: from 180.79 ± 73.33 to 114.65 ± 71.54 [mg/dL], p = 0.031 and study group 2: from 129.62 ± 46.75 to 63.39 ± 43.6 [mg/dL], p < 0.001. Moreover significant drops were observed in concentrations of PTX3: study group 1: from 1336.33 ± 395.15 to 1121.75 ± 351.17 [pg/mL], p = 0.013 and study group 2: from 1610.76 ± 537.78 to 1376.92 ± 529.19 [pg/mL], p = 0.017), and IL-18: study group 1: from 11.89 (9.72–13.98) to 9.15 (8.62–10.06) [pg/mL], p = 0.005 and study group 2: from 11.58 (10.87–16.97) to 9.65 (8.43–10.95) [pg/mL], p = 0.003). There were no significant changes in the levels of sCD40L. Conclusions: This study confirmed the ability of inclisiran to reduce LDL-c levels in patients at high cardiovascular risk just after one dose of the drug. Furthermore, it appeared that beyond its lipid-lowering effect, the drug may also affect some inflammatory processes involved in the initiation and progression of atherosclerosis. Full article

The development of ion exchange chromatography to polish biopharmaceuticals requires extensive experimental benchmarking. As part of the Design of Experiments (DoE), statistical models increased efficiency somewhat and are still state of the art; however, the capability to predict process conditions is limited due to their nature as interpolating models. Applying the DoE still requires numerous experiments and is constrained to the design space, posing a risk of missing the potential optimum. To make a leap in model-based process development, applying extrapolating models can tremendously extend the design space and also allow for process understanding and knowledge transfer. While existing chromatography modeling software explains experimental data, it often lacks predictive power for new conditions. In academic–industrial cooperation, we demonstrate a new high-fidelity model based on biophysics for developing ion-exchange chromatography in biomanufacturing, making it a general tool in rationalizing process development for the present demand of recombinant proteins and monoclonal antibodies and the emerging demand of new modalities. Using the new computational tool, we achieved predictability and attained high accuracy; with minimal experimental effort to calibrate the system, the mathematical model predicted sensitive process conditions, and even described product-related impurities, antibody charge variants. Thus, the computational tool can be deployed for process-by-design and material-by-design approaches. Full article

While urban greenery is known to regulate microclimates and reduce air pollution, its integrated effects remain insufficiently quantified. Through field monitoring and ENVI-met 5.1 modeling of high-rise residential areas in Jinan, the results demonstrate that: (1) vegetation exhibits distinct spatial impacts in air-quality impacts, reducing roadside PM_2.5 by 26.63 μg/m³ while increasing building-adjacent levels by 17.5 μg/m³; (2) shrubs outperformed trees in PM_2.5 reduction (up to 65.34%), particularly when planted in inner rows, whereas tree crown morphology and spacing showed negligible effects; (3) densely spaced columnar trees optimize cooling, reducing T_a by 3–4.8 °C and the physiological equivalent temperature (PET*) by 8–12.8 °C, while planting trees on the outer row and shrubs on the inner row best balanced thermal and air-quality improvements; (4) each 1 m²/m³ leaf area density (LAD) increase yields thermal benefits (ΔT_a = −1.07 °C, ΔPET* = −1.93 °C) but elevates PM_2.5 by 4.32 μg/m³. These findings provide evidence-based vegetation design strategies for sustainable urban planning. Full article

Understanding the competitive adsorption mechanism is essential for the development of adsorptive separation of ethylene (C₂H₄) and ethane (C₂H₆). In this work, density functional theory calculations and molecular dynamics simulations were employed to investigate the adsorption of C₂H₄ and C₂H₆ in two LTA-type zeolites, ITQ-29 and 5A. The results show that the adsorption energies of the gas molecules in zeolite 5A are more negative than in ITQ-29, and the difference in adsorption energy between C₂H₄ and C₂H₆ in zeolite 5A is significantly larger than in ITQ-29, 13.3 versus 6.2 kJ/mol. Zeolite ITQ-29 demonstrates high C₂H₄/C₂H₆ ideal selectivity (43.5 at 5 ns) while exhibiting slow C₂H₄ uptake efficiency due to the small pore windows, hindering C₂H₄ diffusion (1.05 × 10⁻¹⁰ m²/s at 298 K). In contrast, zeolite 5A facilitates the faster diffusion of C₂H₄ molecules (3.25 × 10⁻⁹ m²/s at 298 K) and exhibits a modest C₂H₄/C₂H₆ selectivity of 1.11 at 5 ns in single-gas adsorption and 2.72 in equimolar binary mixture adsorption. To enhance C₂H₄/C₂H₆ selectivity, methyl phosphonic acid is introduced onto zeolite 5A to add a sieving layer that enables the C₂H₄ molecules to preferentially permeate, and the optimal coverage of methyl phosphonic acid is 50%, yielding a C₂H₄/C₂H₆ selectivity of 17.5 at 5 ns in mixture adsorption and preserving the C₂H₄ uptake efficiency. The insights into the competitive diffusion of molecules in the coating layer and inside the zeolites provide a theoretical basis for the rational design of high-performance adsorbents. Full article

In response to the global imperative to reduce greenhouse gas emissions and fossil fuel dependency, electric vehicles (EVs) have emerged as a sustainable transportation alternative, primarily utilizing lithium-ion batteries (LIBs) due to their high energy density and efficiency. However, LIBs are highly sensitive to temperature fluctuations, significantly affecting their performance, lifespan, and safety. One of the most critical threats to the safe operation of LIBs is thermal runaway (TR), an uncontrollable exothermic process that can lead to catastrophic failure under abusive conditions. Moreover, thermal runaway propagation (TRP) can rapidly spread failures across battery cells, intensifying safety threats. To address these challenges, developing advanced battery thermal management systems (BTMS) is essential to ensure optimal temperature control and suppress TR and TRP within LIB modules. This review systematically evaluates advanced cooling strategies, including indirect liquid cooling, water mist cooling, immersion cooling, phase change material (PCM) cooling, and hybrid cooling based on the latest studies published between 2020 and 2025. The review highlights their mechanisms, effectiveness, and practical considerations for preventing TR initiation and suppressing TRP in battery modules. Finally, key findings and future directions for designing next-generation BTMS are proposed, contributing valuable insights for enhancing the safety and reliability of LIB applications. Full article

Network polymers with β-cyclodextrin moieties were prepared by nucleophilic substitution reactions between polyamines, linear polyethyleneimine (LPEI), polyallylamine (PAA), (ε-poly-L-lysine) (EPL), and monochlorotriazinyl-β-cyclodextrin (MCTCD) in methanol/water mixed solvent or water. The reactions under conditions of high material concentration (30 wt%) and a feed ratio of [MCT]/[NH] = 0.5 (mol/mol) successfully yield porous polymers via reaction-induced phase separation. The molecular structure of the polyamines and reaction conditions strongly affected the morphology of the resulting porous polymers. The porous polymers were composed of connected particles, gathered (slightly connected) particles, and/or disordered bulky structures, with sizes of 10⁻⁹ m–10⁻⁸ m. An increase in the molecular weight of LPEI and PAA and the feed molar ratio of [MCT]/[NH] tended to decrease the particle size. Young’s moduli of the LPEI-MCTCD and PAA-MCTCD porous polymers increased with an increase in bulk density, which was derived from small particle sizes. The wide particle size distribution and disordered structure caused collapse by the compression under 50 N of pressure. An LPEI-MCTCD adsorbed methyl orange, methylene blue, and phenolphthalein through ionic interactions, π–π interaction, and/or β-cyclodextrin inclusion. Full article

Hierarchical porous carbon materials hold great potential for energy storage applications due to their high porosity, large specific surface area, and excellent electrical conductivity. Cellulose and sodium alginate are naturally abundant high-molecular-weight biopolymer materials. Utilizing them as precursors for the fabrication of high-performance electrochemical carbon materials is highly significant for achieving carbon neutrality goals. In this study, porous carbon aerogels were successfully synthesized using a combination of freeze-drying and a simple carbonization process, with nanocellulose and sodium alginate as precursors. Among the prepared samples, SC-0.03 (sodium alginate: nanocellulose = 0.1:0.03) exhibited the best performance, achieving a specific surface area of 713.7 m² g⁻¹. This material features an optimized hierarchical pore structure and a substantial intrinsic oxygen doping content, resulting in excellent capacitance performance. Benefiting from these structural advantages and their synergistic effects, the SC-0.03 electrode demonstrated a high specific capacitance of 251.5 F g⁻¹ at a current density of 0.5 A g⁻¹. This study shows that the construction of three-dimensional porous structures by taking advantage of the self-supporting properties of natural polymer materials does not require the introduction of external binders. Due to the nanoscale dimensions and high aspect ratio, nanocellulose enables the formation of a more refined and interconnected hierarchical pore network, enhancing ion accessibility and conductivity. The hierarchical porous carbon aerogel developed in this study, based on a biomass self-reinforcement strategy, not only shows great promise as an advanced energy storage material but also possesses environmentally friendly properties, offering new insights for the development of sustainable energy materials. Full article

Mg alloys are highly attractive for biodegradable surgical clips because of their low density and good biocompatibility; however, their limited strength and ductility restrict their widespread application. To overcome this limitation, this study employed screw rolling (SR) to produce a Mg–3Zn–0.2Ca alloy with a fine microstructure and an average grain size of 1.6 µm. Experimental results showed that the SR process improved the comprehensive tensile properties of the alloy, increasing the yield strength, ultimate tensile strength, and elongation from 192.6, 234.4 MPa, and 21.7% for the pre-extruded alloy to 252.3, 289 MPa, and 39.5%, respectively. Quantitative analysis of the strengthening behaviour identified grain refinement as the primary strengthening mechanism, along with considerable contributions from Orowan and dislocation strengthening. The ultra-high-tensile ductility was primarily attributed to the low internal stress, nano-sized precipitates, texture weakening, and activation of multiple slip systems. These findings provide a strategy for simultaneously increasing the ductility and strength of Mg alloys and lay a foundation for applying them as biodegradable clips. Full article

Small-scale inshore fisheries significantly contribute to the total landing volumes and have an important role in Vietnamese socioeconomic development, food security, livelihoods, and social well-being. The setnet fishery has been used throughout coastal communities of Vietnam for many decades. Being a passive fishing gear, the catch efficiency of setnet depends on various conditions such as fish density, season, oceanography, environment, and others. However, very little information exists about the relationship between catch rates and national conditions. Recognizing this research gap, this study examined the effect of temporal and environmental conditions on the catch rates of the narrow-barred Spanish mackerel (Scomberomorus commerson) setnet fishery using long-term data from 2005 to 2016. Overall, the catch of narrow-barred Spanish mackerel decreased over the course of the study. The generalized additive model (GAM) showed that catch rates were significantly affected by sea surface temperature (SST), which peaked at 27 °C. After this temperature point, the catch rates significantly decreased. Temporal variables also contributed to the catch variation. The setnet caught the highest yield in April and May, and more fish were caught during periods of low nightlight intensity than during high illuminated periods. Our study contributes to the understanding of critical factors affecting the catch rates of valuable species, which helps to determine the optimal fishing process of the setnet fishery within the shifting of marine heatwaves. Full article

Green technology innovation (GTI) is crucial for achieving synergistic development in reducing pollution and carbon emissions (CEs). The spatio-temporal evolutionary aspects of carbon emission intensity (CEI) in resource-based cities (RBCs) and the heterogeneity of the carbon emission reduction effects of GTI from zoning, grading, and classification perspectives are investigated using kernel density estimation, Markov chains, and panel regression models. Our results are as follows: the CEI of RBCs displays a fluctuating downwards trend from 2006 to 2022. Spatially, the main feature is that the north is higher than the south. Second, GTI has significantly reduced the CEI of RBCs through structural optimization, energy savings, and efficiency improvement, as verified in different development stages and dominant resource types. In addition, national high-tech zones (NHTZs) have significantly contributed to reducing CEI in RBCs. The proposed countermeasures include increasing investment in GTI, establishing an exchange platform for GTI, and implementing differentiated policies according to local conditions, which are important for constructing an ecological civilization in RBCs. Full article

Micro-hole aerostatic bearings have emerged as critical components in ultra-precision machining systems, offering a superior load capacity, stiffness, and stability compared to traditional orifice-based designs. These enhancements are primarily attributed to the high-density configurations of micro-holes and the reduction in hole diameter. However, research on the design and analysis of micro-hole aerostatic bearings for high-rotational-speed applications remains limited. In this study, the finite element method (FEM) was employed to solve the Reynolds equation, thereby conducting a systematic evaluation of the static and high-speed performance characteristics of micro-hole aerostatic thrust bearings. The effects of restrictor types, micro-hole layouts, structural parameters, and centrifugal deformation under high-rotational-speed conditions on bearing performance have been comprehensively examined. The objective of this study is to provide a basis for the design of micro-hole high-speed aerostatic spindles. Full article

Recycling in the construction industry is a necessity, not just a fashionable trend in scientific research. The use of coal slag aggregates in concrete means a significant reduction in environmental footprint and should be a priority. For these reasons, this study presents tests of the physical and mechanical properties of high-performance concrete (HPC) with coal slag (CS) used as a replacement for natural coarse aggregate in the amounts of 10%, 20%, and 30% after a long curing time. The investigation determined the porosity, water absorption, density, compressive strength, flexural strength, tensile splitting strength, modulus of elasticity, and ultrasonic pulse velocity (UPV), and analyzed HPC microstructure at 28, 56 days, as well as 2 years of maturation. The use of coal slag resulted in significant increases in compressive strength, flexural strength, and tensile splitting strength compared to reference concrete. However, for HPC with CS, a slight decrease in the elastic modulus and UPV was obtained. The SEM analysis showed a very good adhesion of the cement paste to the slag aggregate. In general, research shows that it is possible to obtain durable high-performance concrete with a 30% replacement of natural aggregate by coal slag. Full article

The article describes a mathematical model of methanol steam reforming taking place at the anode of a molten carbonate fuel cell (MCFC). An artificial neural network with an appropriate structure was subjected to a learning process on the data obtained during an experiment on the laboratory stand for testing high-temperature fuel cells located at the Institute of Heat Engineering of the Warsaw University of Technology. The backpropagation of error method was used to train the neural network. The training data included the results of methanol steam reforming in the fuel cell for steam-to-carbon ratios of 2:1, 3:1, and 4:1. The artificial neural network was then asked to generate results for other steam-to-carbon ratios. As a result, the artificial neural network predicted that the highest power density for a molten carbonate fuel cell working on methanol would be obtained with a steam-to-carbon ratio of 2.8:1. The article’s key achievement is the application of artificial intelligence to calculate an unusual steam-to-carbon ratio for the methanol steam reforming process occurring directly at the anode of an MCFC fuel cell. The solution proposed in the article contributed to reducing the number of experimental studies. Full article