Conventional cutting fluids often rely on non-renewable mineral oils and hazardous additives, raising serious environmental and occupational safety concerns. Developing green, high-performance alternatives is therefore imperative for advancing sustainable manufacturing. Amphiphilic Fe3O4@SiO2-C12 core-shell nanoparticles were synthesized and used to stabilize vegetable oil-in-water Pickering emulsions as novel nano-cutting fluids. Systematic characterization confirmed the successful formation of superparamagnetic nanoparticles with tunable wettability. Response surface methodology (RSM) optimized the formulation to pH 8.9, 2.9 wt% cottonseed oil, and 0.18 wt% nanoparticles, achieving a zeta potential of −42.533 mV and wear scar diameter of 0.393 mm. The optimized Pickering emulsion demonstrated superior performance versus the commercial cutting fluid, including a low friction coefficient of 0.0666, a 17.09% reduction in wear scar diameter, a 10.21% decrease in tapping torque, and a 15.40% enhancement in thermal conductivity (0.645 W/(m·K)). X-ray photoelectron spectroscopy (XPS) and scanning electron microscope (SEM)-energy-dispersive spectroscopy (EDS) revealed a triple synergistic lubrication mechanism involving physical adsorption, tribochemical Fe2O3/FeO film formation, and nanoparticle-enabled micro-bearing and heat conduction. The Pickering emulsion also demonstrated excellent magnetic responsiveness, enabling rapid, magnetically controlled demulsification and oil-water separation for recycling. In this work, a high-performance and environmentally friendly cutting fluid was developed and evaluated for sustainable manufacturing applications.
Nitrogen oxides (NOx) are major atmospheric pollutants contributing to acid rain and photochemical smog. Selective catalytic reduction with ammonia (NH3-SCR) is a widely adopted technology for NOx removal, where catalyst design critically governs low-temperature efficiency. Graphene-based catalysts demonstrate exceptional potential in this context due to their tunable surface chemistry, high electron mobility, and thermal stability. This review comprehensively analyzes synthesis strategies, including chemical vapor deposition (CVD), sol–gel, hydrothermal, and solvothermal methods, and their correlation with catalytic morphology and activity. We specifically elucidate how oxygen/nitrogen functional groups and defect engineering enhancing NOx adsorption activation while mitigating sulfur poisoning through spatial confinement effects. The integration of computational modeling with experimental characterization reveals structure–activity relationships in graphene-supported metal clusters. Current challenges in scalable manufacturing and long-term stability under humid conditions are critically assessed, providing guidelines for advancing graphene catalysts toward industrial implementation.
In this paper, a custom-designed fixed-bed reactor was employed for the pyrolysis of wheat, corn, and sorghum straw at 300-500 degrees C, and the derived liquid products were systematically characterized via GC-MS. Wood vinegar was refined from wheat straw pyrolysis liquid, with its chemical composition and antimicrobial performance evaluated. Furthermore, wheat straw-derived pyrolytic carbon was applied for low-alcohol Baijiu clarification, and its effects on the liquor's physicochemical properties and flavor profile were systematically assessed. The results showed that the liquid products of the three straws shared similar component categories (dominated by acids, ketones, esters, alcohols, aldehydes and phenols), with consistent variation trends of component distribution along with pyrolysis temperature. The refined wood vinegar was dominated by acetic acid, and achieved over 99% antimicrobial efficiency against Escherichia coli and Candida albicans at 20-fold dilution. The optimal clarification condition was determined as 2.5 g/L pyrolytic carbon dosage with 30 h treatment; under this condition, the liquor transmittance was significantly improved, with only 6.29% loss of total esters, and the original typical flavor profile of the liquor was well retained. This work provides valuable data and technical reference for the full-component high-value utilization of agricultural straw.
We introduce an interface multicontinuum homogenization method (I-MCHM) for high-contrast elliptic problems whose subdomains may have distinct microscopic patterns and unequal numbers of continua. Multicontinuum models upscale microscopic fields to macroscopic continuum quantities; here the continua are the high- and low-permeability regions, and the macroscopic variables are the corresponding local averages of the fine-scale solution on observing cells of size H_ε. Although the fine-scale solution is continuous across a material interface, these macroscopic continuum fields need not coincide on the interface. Moreover, when adjacent subdomains retain different numbers of continua, a one-to-one coarse transmission condition cannot be defined. Standard subdomain-wise multicontinuum homogenization therefore determines the bulk equations but leaves the interaction among these coarse variables unspecified. I-MCHM closes this gap by constructing two-sided constrained local bases on interface neighborhoods and assembling a coarse bilinear form with bulk cut-cell integrals and interface-segment corrections over the subdomain adjacency graph, without prescribing a pointwise transmission law. Numerical experiments on straight, curved, and triple-junction geometries, including continuum-coupling ablations and unequal continuum counts, demonstrate the accuracy of the resulting upscaled model.
This study aims to elucidate the relationship between the molecular structure characteristics of shale asphaltene and shale gas preservation in the Sichuan Basin, China, through integrated experimental characterization and molecular simulation. Asphaltene samples were analyzed using elemental analysis, Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and nuclear magnetic resonance (NMR). Molecular simulations revealed that stronger methane-asphaltene interactions (total interaction energy: -186.59 to -238.54 kJ/mol) and lower solubility parameters (16.55-19.57 (J/cm(3))(1/2)) enhance shale gas retention. Aromatic cores are predominantly peri-condensed (the ratio of aromatic hydrogen to aromatic carbon, H-AU/C-A > 0.5), favoring gas adsorption. Two predictive models based on microstructural parameters (using a threshold of the product of crystallite height and the number of aromatic carbon atoms, L*C 60.59) classify samples by gas content. The novelty of this work lies in establishing a microstructure-based predictive framework for shale gas preservation, integrating multi-scale experimental and computational approaches to provide practical insights for efficient shale gas exploration and development.
