Search Results (7,635)

Contacted liquid fluids, in most cases, have the tendency to directly merge into a single larger fluid to minimize the surface energy. We present an abnormal drop formation process of contacted Cu liquid films with a radius of 101.7 Å or larger on carbon substrates by using molecular dynamics simulations. The formation process consists of consecutive pinch-off and full coalescence stages connected by detachment. The dominant motions of the bridge, away from the center and downward to the substrate, lead to the pinch-off of the initially connected droplets. The motions of the droplets, which are near each other at all times, leads to the repeated contact and full coalescence of the separated droplets. The abnormality is attributed to the competition between the motions of the droplets and the tiny liquid bridge that connects the droplets. The influence of the surface structures of substrates, especially carbon nanotubes, on the formation behavior is discussed by analyzing the mean square displacement, velocity fields, and density and scaling profiles. This study provides guidance for controlling drop formation behavior by regulating the surface structures of carbon substrates. Full article

Wood is a renewable and sustainable environmentally friendly building material. With proper design, it can help buildings achieve lower carbon emissions. However, since wood is a flammable material, its combustion performance in fires has attracted attention. In modern timber structures, glulam is a widely used engineered wood product. Thus, in this paper, glulam specimens made of four kinds of commonly used soft-wood species were used to compare their combustion performance, and the cone calorimeter method was employed. The indicators including time to ignition, heat release rate per unit area, total heat release per unit area, specific extinction area per unit mass, mass of residue, yield of CO and yield of CO₂ were evaluated and compared. The results showed that all the glulam specimens would experience cracking wood and adhesive layer. The time to ignition and peak mass loss rate of the four softwood species in the study was positively correlated with their density. Among these species, Spruce exhibited the highest peak heat release rate and the highest peak CO₂ yield but lowest smoke production, while Douglas fir had a relatively late CO production time and the lowest mass loss percentage, Larch had the lowest heat release rate and total heat release. This study provides fundamental data for the selection of wood structural materials and for future research on wood flame-retardant treatments. Full article

The purpose of this study was to evaluate how a multi-component soil conditioner consisting of zeolite, calcium carbonate, potassium humate, and Ascophyllum nodosum extract affects selected soil properties (physical, chemical, and water-related properties, as well as microbial and enzymatic properties) and the growth and grain yield of spring barley (Hordeum vulgare L.). To achieve the goal, one-year research experiments were conducted at three conventionally tilled sites, which were situated on farms across three geographically separate regions in the Kuyavian–Pomeranian Region of Midwestern Poland. Most of the chemical properties, namely, total organic C, total N, pH in KCl, cation exchangeable capacity (CEC), as well as exchangeable (Mg, Ca, K, and Na) and available (Mg, K, and P) forms of nutrients, were not significantly affected by the conditioner or sampling time. Independent of the study location, the percentage of macropores in total porosity (TP) and dissolved nitrogen content (DNt) determined in July were considerably greater in the soil treated with Solactiv compared to the reference soil. Bulk density (BD), in turn, showed the opposite tendency, also suggesting the positive effect of the studied conditioner. At all study sites, application of the conditioner significantly reduced the percentage of micropores in total porosity (TP) (by 17%), while significantly increasing the content of macropores in TP (15%) and enhancing the percentage of available and readily available water capacity (8.5% and 14%). No clear changes in the results of C and N form and enzymatic activity were noted. The activities of DHA and FDAH behave differently in each study site, making it difficult to draw clear conclusions. The cellulase was the only enzyme that was significantly and positively affected by Solactiv at all study sites and for both sampling times. The values of dry matter of roots and plants, barley root length and surface, and barley grain yield were considerably greater in soil amended with Solactiv compared to the reference soil. Because some important soil and plant properties showed a positive response toward the tested conditioner, despite the low dose used, further studies should be conducted at a larger scale, focusing on different soils and plants. Full article

Magnesia-dolomite refractories have emerged as sustainable alternatives to traditional carbon- or chromium-containing linings in steelmaking and cement industries. Their outstanding thermochemical stability, high refractoriness, and strong basic slag compatibility make them suitable for converters, electric arc furnaces (EAF), and argon–oxygen decarburization (AOD) units. However, their practical application has long been constrained by hydration and thermal shock sensitivity associated with free CaO and open porosity. Recent advances, including optimized raw material purity, fused co-clinker synthesis, nano-additive incorporation (TiO${}_2$, MgAl${}_2$O${}_4$ spinel, FeAl${}_2$O${}_4$), and improved sintering strategies, have significantly enhanced density, mechanical strength, and hydration resistance. Emerging technologies such as co-sintered magnesia–dolomite composites and additive-assisted microstructural tailoring have enabled superior corrosion resistance and extended service life. This review provides a comprehensive analysis of physicochemical mechanisms, processing routes, and industrial performance of magnesia–dolomite refractories, with special emphasis on their contribution to technological innovation, decarbonization, and circular economy strategies in high-temperature industries. Full article

In this study, sheets of experimental high-carbon low-density steels (LDSs) with a thickness of 1.7 mm were processed in a combined tool designed for press-hardening. Press hardening, also known as hot stamping or hot press forming, is a manufacturing process used to create car body parts with exceptional mechanical properties and safety standards. These components often require tailored properties, meaning different mechanical characteristics in various parts of the component. LDSs have a lower specific density than conventional steels, so their use would be particularly suitable in automotive applications. Combined tools achieve distinct mechanical properties within a single part through thermomechanical processing. Simultaneous forming and heat treatment create tailored zones of high strength and ductility within the sheet metal. The hardened zone provides crashworthiness, while the more ductile zone absorbs kinetic energy and converts it into deformation energy. Hot stamping enables forming complex geometries from high-strength sheets with limited cold formability, a capability that can also be exploited for the aluminium-alloyed LDS under investigation in this work. Three different high-carbon LDSs with differences in chemical composition were subjected to this experiment, and the hardness, microstructure, and mechanical properties of the two areas of each sheet were evaluated. The aim is to determine their suitability for processing by press hardening and to try to achieve tailored properties (i.e., differences in ductility and strength across one part) as in a typical representative of 22MnB5 boron steel, where a strength limit of 1500 MPa at 5% ductility is achieved in the cooled part and 600 MPa at 15% in the heated part. Tailored properties were also achieved in the investigated LDS, but with only relatively small differences between the two tool areas. The omega profiles were produced by press hardening without visible defects, and it was possible to process the steels without any difficulties. Full article

Understanding interactions among ecosystem services (ESs) is vital for ecological conservation and governance. As a newly established national-level New Area in China, Xiong’an New Area holds significant ecological importance. This study first explores its long-term spatiotemporal changes in ESs using an “assessment-attribution-correlation-zoning” framework. Results show that net primary productivity (NPP) remained stable from 1990 to 2023; soil conservation (SC) and habitat quality (HQ) improved from 2018 to 2023; carbon storage (CS) declined significantly from 2010 to 2015; and water yield (WY) decreased continuously from 1990 to 2023. Rainfall was the key natural driver, while GDP and road network density were critical anthropogenic factors. Correlations among the five ESs weakened: synergies between soil conservation–water yield, soil conservation–carbon storage, soil conservation–habitat quality, water yield–carbon storage, and habitat quality–carbon storage diminished, and the water yield–habitat quality synergy turned into a trade-off. Spatial autocorrelation analysis revealed significant spatial heterogeneity in ESs. Carbon storage–habitat quality, carbon storage–soil conservation, habitat quality–soil conservation, net primary productivity–habitat quality, water yield–soil conservation, and net primary productivity–water yield showed low-low clustering; net primary productivity–carbon storage, net primary productivity–soil conservation, and water yield–habitat quality exhibited low-high clustering; and water yield–carbon storage showed high-high clustering. Finally, ESs were classified into six bundles via self-organizing maps, with the carbon–ecology maintenance bundle being the largest. These findings provide a basis for scientific ecosystem management and sustainable development in Xiong’an. Full article

Against the backdrop of China’s “carbon peaking” and “carbon neutrality” goals, as well as the advancement of new industrialization, the oil and gas industry is undergoing a critical transformation from resource-dependent growth toward innovation-driven, low-carbon, and high-quality development. The integrated advancement of high-end, intelligent, and green transformation—collectively referred to as the “Three Modernizations”—has become a vital pathway for promoting industrial upgrading and sustainable growth. Based on panel data from 30 Chinese provinces from 2009 to 2023, this study constructs a comprehensive evaluation index system covering 19 secondary indicators across three dimensions: high-end, intelligent, and green development. Using the entropy-weighted TOPSIS method, kernel density estimation, Dagum Gini coefficient decomposition, and σ–β convergence models, the study examines the spatiotemporal evolution, regional disparities, and convergence characteristics of HIG integration, and further explores its driving mechanisms through a two-way fixed effects model and mediation effect analysis. The results show that (1) the overall HIG integration index rose from 0.34 in 2009 to 0.46 in 2023, forming a spatial pattern of “high in the east, low in the west, stable in the center, and fluctuating in the northeast”; (2) regional disparities narrowed significantly, with the Gini coefficient declining from 0.093 to 0.058 and σ decreasing from 7.114 to 6.350; and (3) oil and gas resource endowment, policy support, technological innovation, and carbon emission constraints all positively promote integration, with regression coefficients of 0.152, 0.349, 0.263, and 0.118, respectively. Heterogeneity analysis reveals an increasing integration level from upstream to downstream, with eastern regions leading in innovation-driven development. Based on these findings, the study recommends strengthening policy and institutional support, accelerating technological innovation, improving intelligent infrastructure, deepening green and low-carbon transformation, promoting regional coordination, and establishing a long-term monitoring mechanism to advance the integrated high-quality development of China’s oil and gas industry. Overall, this study deepens the understanding of the internal logic and spatial dynamics of the “Three Modernizations” integration in China’s oil and gas industry, providing empirical evidence and policy insights for accelerating the construction of a low-carbon, secure, and efficient modern energy system. Full article

The search for high-capacity, stable anode materials is crucial for advancing lithium-ion battery (LIB) technology. Although carbon nanotubes (CNTs) are known for their excellent electrical conductivity and mechanical strength, their practical capacity is still limited. This study presents an advanced anode design by molecular functionalizing both single-walled and multi-walled carbon nanotubes (SWCNTs and MWCNTs) with tetrabromocobalt phthalocyanine (CoPc), resulting in CoPc/SWCNT and CoPc/MWCNT hybrid materials. Metal phthalocyanines (MPcs) are recognized for their tunable and redox-active properties. In CoPc, the redox-active metal centers and π-conjugated structure are uniformly attached to the CNT surface through strong π-π interactions. This synergistic combination significantly boosts the lithium-ion (Li-ion) storage capacity by offering numerous coordination sites for Li-ions and enhancing charge transfer kinetics. Electrochemical analysis shows that the CoPc-SWCNT active anode electrode material shows an impressive reversible capacity of 1216 mAh g⁻¹ after 100 cycles at a current density of 0.1 A g⁻¹, substantially surpassing the capacities of pristine CoPc (327 mAh g⁻¹) and a CoPc/MWCNT hybrid (488 mAh g⁻¹). Furthermore, the CoPc/SWCNT anode exhibited exceptional rate capability and outstanding long-term cyclability. These results underscore the effectiveness of non-covalent functionalization with SWCNTs in enhancing the electrical conductivity, structural stability, and active site utilization of CoPc, positioning CoPc/SWCNT hybrids as a highly promising anode material for high-performance Li-ion storage. Full article

Blue carbon ecosystems, particularly mangroves, seagrasses, and salt marshes, play a crucial role in climate regulation by capturing and storing huge stocks of carbon. Together with supporting fisheries production, protecting shorelines from erosion, and supplying timber and non-timber products to communities, blue carbon ecosystems offer investment opportunities through carbon markets, thus supporting climate change mitigation and sustainable livelihoods. The current study assessed above- and below-ground biomass, sediment carbon, and the capacity of the blue carbon ecosystems in Kwale and Lamu Counties, Kenya, to capture and store carbon. This was followed by mapping of hotspot areas of degradation and the identification of investment opportunities in blue carbon credits. Carbon densities in mangroves were estimated at 560.23 Mg C ha⁻¹ in Lamu and 526.34 Mg C ha⁻¹ in Kwale, with sediments accounting for more than 70% of the stored carbon. In seagrass ecosystems, carbon densities measured 171.65 Mg C ha⁻¹ in Lamu and 220.29 Mg C ha⁻¹ in Kwale, values that surpass the national average but are consistent with global figures. Mangrove cover is declining at 0.49% yr⁻¹ in Kwale and 0.16% yr⁻¹ in Lamu, while seagrass losses in Lamu are 0.67% yr⁻¹, with a 0.34% yr⁻¹ increase in Kwale. Under a business-as-usual scenario, mangrove loss over 30 years will result in emissions of 4.43 million tCO₂e in Kwale and 18.96 million tCO₂e in Lamu. Effective interventions could enhance carbon sequestration from 0.12 to 3.86 million tCO₂e in Kwale and 0.62 to 19.52 million tCO₂e in Lamu. At the same period, seagrass losses in Lamu would emit 5.21 million tCO₂e. With a conservative carbon price of 20 USD per tCO₂e, projected annual revenues from mangrove carbon credits amount to USD 3.59 million in both Lamu and Kwale, and USD 216,040 for seagrass carbon credits in Lamu. These findings highlight the substantial climate and financial benefits of investing in the restoration and protection of the two ecosystems. Full article

Sustainable soil management is crucial for balancing agricultural productivity and soil health in Mollisols under long-term tillage systems. This study evaluated the effects of no-tillage (NT), minimum conservation tillage (MCT), and conventional tillage (CT) on soil properties and maize yield in an irrigated Mollisol in Chapingo, Mexico, over 9, 22, and 25 yr, using a Latin square design with three replications. MCT significantly enhanced soil organic carbon (SOC), total nitrogen (TN), available phosphorus (AP), and exchangeable potassium (EK) compared to NT and CT, achieving the highest maize grain yield (7.21 t ha⁻¹). NT exhibited the greatest SOC and EK in the surface layer. Physical properties, such as bulk density and porosity, remained stable across systems, reflecting Mollisol resilience. Although MCT optimized fertility and productivity, nutrient declines from 2021 to 2024 highlight the need for adaptive management strategies to sustain long-term productivity, supporting global soil conservation and sustainable agriculture goals. Full article

Zeolitic imidazolate frameworks (ZIFs) can provide fascinating stereo morphology and tunable metal active sites, which plays an important role in the synthesis of various catalytic materials. However, it is still a problem to make use of these advantages to design efficient hydrogen evolution reaction (HER) catalysts. Herein, we use covalent coordination strategy to synthesize bimetallic Co_xZn_1−x(2-MeIM)₂ precursors with regular dodecahedral structures for providing uniform active sites and stable carbon skeleton. Furthermore, the ratio of Co and Zn atoms was optimized to balance the electron density and give full play to the synergistic catalytic effect. And then, the subsequent high temperature annealing process is used to construct the amorphous carbon layer, which can improve the overall stability of the material. The gas phase phosphating process realizes the transformation from ZIF material to metal phosphide resulting in enhanced hydrogen evolution activity. Finally, the optimized amorphous nitrogen-doped carbon (NC)-coated Zinc-doped cobalt phosphide (Zn_0.17Co_0.83P@NC) requires only 237.60 mV to reach the current density of 10 mA cm⁻² in alkaline medium, which is 223.22 mV lower than that of CoP, and has a stability of up to 18 h. This work provides a reference for the rational design of efficient and stable compound electrocatalysts for alkaline hydrogen evolution based on the bimetallic ZIF as a precursor. Full article

This study investigated sawdust-derived activated carbon (SAC) as a sustainable reinforcing filler for vulcanized rubber bushings (VRBs). Two types SAC200 (75 µm, carbonized at 200 °C) and SAC400 (38 µm, carbonized at 400 °C) were chemically activated and incorporated into natural rubber (NR) at 25–55 phr loadings, while SAC free VRBs served as controls. Fourier transform infrared (FTIR) analysis revealed that SAC400 exhibited stronger hydroxyl and carbonyl functional groups, indicating higher surface reactivity compared with SAC200. The incorporation of SAC increased cross-linking density, thereby enhancing both curing behavior and mechanical performance. VRBs reinforced with SAC400 demonstrated higher maximum torque (up to 38.07 kg·cm), shorter scorch time (5 min 58 s), and reduced cure time (11 min 05 s) relative to SAC200 and the control. Mechanical properties improved markedly, with hardness and tensile strength rising from 45 Shore A and 5.52 MPa in the control to 70 Shore A and 13.40 MPa in SAC400. Although elongation at break decreased slightly, it remained within the acceptable range for dynamic applications. Swelling resistance also increased, reaching 101.76% at 25 °C and 106.61% at 100 °C. Overall, SAC400 consistently outperformed SAC200 and the control, highlighting its potential as a renewable, biomass-derived filler for high-performance rubber bushings and promising a sustainable alternative to conventional fillers in industrial applications. Full article

China is developing renewable energy bases (REBs) in the desert and Gobi regions. However, the intermittency of renewable energy and the temporal mismatch between peak renewable generation and peak load demand severely disrupt the power supply reliability of these REBs. Hydrogen storage technology, characterized by high energy density and long-term storage capability, is an effective method for enhancing the power supply reliability. Therefore, this paper proposes a REB planning model in the desert and Gobi regions considering seasonal hydrogen storage introduction as well as electricity-carbon-hydrogen markets trading. Furthermore, a combination scenario generation method considering extreme scenario optimization is proposed. Among which, the extreme scenarios selected through an iterative selection method based on maximizing scenario divergence contain more incremental information, providing data support for the proposed model. Finally, the simulation was conducted in the desert and Gobi regions of Yinchuan, Ningxia Province, China, primarily verifying that (1) the REB incorporating hydrogen storage can fully leverage hydrogen storage to achieve seasonal and long-term electricity transfer and utilization. The project has a payback period of 10 years, with an internal rate of return of 13.30% and a return on investment of 16.34%, thus showing significant development potential. (2) Compared to the typical battery-involved REB, the hydrogen-involved energy storage facility achieved a 59.39% annual profit, a 10.98% internal rate of return, a 14.93% return on investment, and a 1.51% improvement in power supply reliability by sacrificing a 52.49% increase in construction cost. (3) Compared to REB planning based only on typical scenarios, the power supply reliability of REBs based on the proposed combination scenario generation method improved by 8.58%. Full article

Compressed carbon dioxide energy storage (CCES) has emerged as a promising solution for long-duration energy storage owing to its high energy density, adaptability to diverse environments, and compatibility with carbon capture technologies. This study develops a dynamic MATLAB 2024a/Simscape model for a 10 MW × 8 h gas–liquid CCES (GL-CCES) system featuring two-stage compression and two-stage expansion. Constant-pressure operation is maintained by check and throttle valves at the boundaries of the high-pressure tank. After startup, all system variables except those associated with the storage tank stabilize rapidly. The analysis reveals several critical dynamic phenomena: (1) a persistent mass-flow imbalance between charging and discharging processes under constant-pressure operation; (2) distinct phase transitions within the high-pressure tank that produce inflection points in thermodynamic evolution; and (3) strong ambient-temperature sensitivity that dictates system stability and efficiency boundaries. The system achieves a round-trip efficiency of 70.52% at 25 °C, which decreases to 67.01% at 21 °C. More importantly, the dynamic energy density (5.15 kWh m⁻³) is only 12.7% of the steady-state reference value. These results demonstrate the feasibility of GL-CCES for large-scale, long-duration energy storage, while also highlighting its pronounced sensitivity to ambient conditions, underscoring the need for optimized design and adaptive operational strategies. Full article

Electrocatalytic water splitting offers a promising route to sustainable H₂, but the oxygen evolution reaction (OER) in alkaline media remains the principal bottleneck for activity and durability. This review focuses on alkaline OER and integrates mechanism, kinetics, materials design, and cell-level considerations. Reaction mechanisms are outlined, including the adsorbate evolution mechanism (AEM) and the lattice oxygen mediated mechanism (LOM), together with universal scaling constraints and operando reconstruction of precatalysts into active oxyhydroxides. Strategies for electronic tuning, defect creation, and heterointerface design are linked to measurable kinetics, including iR-corrected overpotential, Tafel slope, charge transfer resistance, and electrochemically active surface area (ECSA). Representative catalyst families are critically evaluated, covering Ir and Ru oxides, Ni-, Fe-, and Co-based compounds, carbon-based materials, and heterostructure systems. Electrolyte engineering is discussed, including control of Fe impurities and cation and anion effects, and gas management at current densities of 100–500 mA·cm⁻² and higher. Finally, we outline challenges and directions that include operando discrimination between mechanisms and possible crossover between AEM and LOM, strategies to relax scaling relations using dual sites and interfacial water control, and constant potential modeling with explicit solvation and electric fields to enable efficient, scalable alkaline electrolyzers. Full article