Abundant aquatic environments and sufficient material supplies in lacustrine rift basins favor organic matter (OM) accumulation. However, how multistage faulting intensity, tectonic styles, and resultant paleogeomorphological evolution jointly regulate OM enrichment remains unclear, particularly the spatial heterogeneity of such controls across different sag settings. Taking three sags across the central-eastern Bohai Bay Basin (Bozhong Sag (BZS), southern subsag of the Liaozhongnan Sag (SLZS), and Bodong Sag (BDS)) as the target, this study conducted integrated analysis of organic and elemental geochemistry of the organic matter. The spatiotemporal dynamics of organic matter distribution was revealed, and sedimentary environments were reconstructed. By integration with paleogeomorphological analysis, this study elucidates the control of tectonic dynamics on OM enrichment. Results show that during the tectonically stable period, wide-shallow, high-salinity waters dominated by intrabasinal material inputs preserve abundant Type I OM. During the tectonically active stage, spatial variations in fault activity intensity and tectonic styles shaped the basin's geomorphology with alternating sags and uplifts, increasing extra-basinal material input and leading to mixed OM sources. The BZS (basin center) was mainly controlled by extensional activities, resulting in deep, extensive waters. Gentle topography facilitated unimpeded clastic input; however, the concomitant inflow of riverine freshwater was unfavorable to OM preservation. The SLZS, affected by strike-slip extensional activity, formed a local topographic high with shallow waters, where continuous hydrodynamic disturbance and limited terrestrial OM input inhibited OM accumulation. The BDS (marginal sag), influenced by multidirectional overlapping strike-slip/extensional activities, had enclosed deep saline waters due to peripheral uplifts and is the optimal condition among coeval sags. A conceptual model for OM enrichment was established, which aids in predicting high-quality source rocks and in guiding shale oil/gas exploration in continental lacustrine rift basins.
Hydrogels are polymeric matrices very similar to living tissue due to their elasticity, porosity, and ability to absorb high water content. They are highly attractive materials for a wide range of biomedical applications, such as tissue engineering, wound healing, and drug delivery. In this regard, hydrogels of semi-interpenetrating polymer networks (semi-IPNs) based on the biopolymers chitosan and poly-(γ-glutamic acid) (γ-PGA) were prepared as systems with improved properties compared to hydrogels of individual polymers. The resulting hydrogels were characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), porosity testing, compressive strength, cell viability, and swelling capacity. FTIR spectra of the semi-IPNs confirmed the presence of the functional groups of each polymer. SEM images revealed a porous structure of the hydrogels, which became denser and more compact with increasing γ-PGA content. This behavior was corroborated by the porosity test, which decreased with the formation of the γ-PGA-reinforced network. The swelling capacity study of the hydrogels demonstrated their sensitivity to pH and temperature. For the semi-IPN hydrogels, SF1 had the highest swelling ratio (20.55) at pH 3.6 and T = 37 °C. The formation of the semi-IPNs brought about improvements in mechanical properties compared to the chitosan hydrogel. The presence of γ-PGA contributed to improved biocompatibility of the materials, especially in formulations with 0.025 and 0.05 g of this biopolymer. These results suggest that the obtained chitosan/γ-PGA semi-interpenetrating networks may be promising materials with great potential for use in biomedical applications.
Methanol steam reforming is a promising method to achieve on-site hydrogen production for fuel cell applications. The characteristics of fluid flow, heat transfer, and mass transfer within advanced reactors still call for further investigation. A computational fluid dynamics simulation study of methanol steam reforming in a monolith reactor based on multiscale modeling is presented in this work. The washcoat model reveals that effectiveness factors decrease with increasing coating thickness and temperature, but H2 production alleviates diffusion limitations, allowing such effects to be neglected in downstream regions. The reactor model shows that product selectivity is primarily governed by temperature, with higher temperatures promoting methanol decomposition and thereby increasing CO formation. Methanol conversion and H2 yield are also strongly temperature-dependent, while the substrate of high thermal conductivity and larger length-to-diameter ratios improve thermal uniformity and performance. Additionally, methanol conversion declines with higher reactant flow rates, although higher flow rates enhance the absolute H2 yield. Honeycomb substrates should be designed to possess high cell density and thin channel walls, which poses challenges for mechanical properties and manufacturing. In addition, under conditions of low flow velocity, diffusion phenomena at the reactor inlet require particular attention in numerical simulations.
Traditional bentonite grease suffers from inadequate tribological properties. Layered double hydroxides (LDHs) have great potential as lubricant additives owing to their unique lamellar structure, tunable chemical composition, and high anion-exchange capacity, which enable strong interfacial interactions and stable dispersion in lubricating media. In this study, Mg Al-layered double hydroxide (MA-LDH) was synthesized as a crystalline lamellar compound with a controllable morphology and particle size. MA-LDH was prepared under hydrothermal conditions at pH 8-12 and 120-180 °C. The effects of MA-LDH synthesis conditions and additive concentration on the properties of bentonite grease were systematically investigated. Scanning electron microscopy revealed that the particle size distribution of MA-LDH became increasingly nonuniform as the pH and hydrothermal temperature increased. MA-LDH synthesized at pH 10 and 120 °C exhibited excellent particle size uniformity and dispersibility. Within the investigated additive range (0.1-12 wt %), an MA-LDH concentration of 1.5 wt % produced the best tribological performance. Compared with the base bentonite grease, the grease containing 1.5 wt % MA-LDH showed a 34.2% reduction in average coefficient of friction, an 89.2% decrease in wear volume, and a 150% increase in load-carrying capacity. The incorporation of MA-LDH optimizes load distribution, facilitates interfacial sliding, and enhances the film-forming ability, thereby improving the tribological performance of the bentonite grease.
The study on the hydraulic fracturing potential of coalbed methane (CBM) reservoirs aims to assess the ability of coal seams to increase permeability and gas well productivity under the action of hydraulic fracturing. It provides a theoretical basis and technical support for optimizing reservoir fracturing design and improving the efficiency of CBM development, thereby addressing the issue of unstable production enhancement effects of the reservoirs. This review analyzes the primary factors influencing the hydro-fracturing potential of CBM reservoirs, taking into account both geological conditions and mechanical characteristics, and discusses the key physical and numerical simulation techniques for stimulating CBM reservoirs. Physical simulation techniques mainly focus on pore-fracture structure characterization, rock mechanics testing, logging interpretation, and injection falloff testing in the well. Numerical simulation technologies mainly focus on geomechanics simulation, digital core simulation, fracture propagation simulation, and fracturing operation simulation. There are many problems in the current research. The results of indoor tests differ significantly from the field application effects. The calculation accuracy of the evaluation parameters for the hydro-fracturing potential of CBM reservoirs is low. The construction of digital models is influenced by mathematical statistical methods, leading to the fallacy of equivalent cognition. The prediction of the fracturing improvement effect of CBM reservoirs faces systematic deviations in engineering applications. There is a lack of a comprehensive evaluation system that covers the coordination of multienergy systems, as well as environmental and economic factors. The analysis suggests that the breakthrough paths for future research should focus on the following aspects. Improve the physical compatibility between the experimental conditions and the actual reservoir environment. Innovate modeling methods that integrate geological measurement mechanisms and data-driven approaches. Establish a dynamic simulation system that covers the evolution of multi-scale fractures and the coupling of stress. Construct a multi-source dynamic evaluation system that integrates the goals of energy integration systems, environmental constraints, and economic benefits. This is to establish a geological-engineering collaborative research framework covering the entire time and space domain, thereby promoting the precise and efficient transformation of reservoirs and the efficient development of CBM.
As is known, colorless polyimide (CPI) is usually regarded as a substrate material for transparent flexible printed circuit boards (FPCB) as a high-performance optical-grade polymer film. The problem of CPI films being nonwetting with the metal interface in the preparation of transparent FPCB urgently needs to be solved. The 6FDA and 3FPODA monomers containing flexible structures were selected to prepare CPI films with TFDB by the copolymerization reaction for improving the optical properties. Two series of copolymerized CPI films (3F6FP/C-PI-x and 3F6FP/H-PI-x) with different ratios of dianhydride were prepared by using chemical imidization and thermal imidization methods. The solubility, optical properties, thermal properties, and mechanical properties of the two series of CPI films were characterized to explore the introduction of the 3FPODA monomer on the optical, thermal, and mechanical properties of CPI films. According to the research on the two series of copolymerized CPI films, it was found that the introduction of 3FPODA and 6FDA with a copolymerization method could improve the thermal and mechanical properties of optical-grade CPI films significantly. The optical, thermal, and mechanical properties of the CPI films prepared by the chemical imidization method are superior to those of the CPI films prepared by the thermal imidization method, which indicates that the chemical imidization method is more suitable for preparing such optical-grade CPI films. Based on the most excellent comprehensive performance, the optical indicators and other key properties of the 3F6F/C-PI-4 CPI film could meet the requirements for preparing transparent FPCB.
Soft tissue injuries resulting from trauma or degeneration are challenging to treat due to limited regenerative capacity, particularly in complex tissues, such as the central nervous system (CNS), nerves, and cartilage, where biomechanical and biochemical factors hinder effective repair. In these cases, tissue engineering presents a promising approach by combining biomaterials, cells, and bioactive signals to enhance soft tissue regeneration; however, its success relies on the compatibility between implanted materials and native tissue. Among the advances in this field, 3D bioprinting enables precise spatial control of the scaffold architecture and cell positioning, making it well-suited for developing constructs that mimic native tissue. In this study, we developed and characterized a series of bioink formulations based on a dual network system of gelatin methacrylate (GelMA) combined with gellan gum (GG). The GelMA/GG hydrogels were evaluated using rheological and compression testing as well as biodegradation and cell viability assays, including live/dead fluorescence microscopy. Formulations containing two different concentrations of GelMA (2.5 and 4.0% w/w) and GG (0.25 and 0.50% w/w) were tested, and the rheological results showed a strong dependence of the elastic component (G') on GG concentration. For the 2.5% GelMA formulations, increasing the GG content significantly enhanced the Young's modulus. In 4.0% GelMA formulations, stiffness increased as the GG concentration rose. Higher GG content decreased biodegradation over 14 days in phosphate-buffered saline and reduced cell viability due to the hydrogel's increased stiffness. The bioinks demonstrated suitable rheological properties for bioprinting, achieving over 98% cell viability after 1 day. Additionally, formulations such as 4.0% GelMA with 0.25% GG and 2.5% GelMA with 0.5% GG exhibited high cell viability (above 85%) when maintained even after longer culture periods, such as 14 days. These results indicate that GelMA/GG hydrogels have great potential as versatile, tunable bioinks for soft-tissue engineering in the CNS. Future research will focus on modifying the hydrogel network's rigidity to enhance cell viability further and refine its application in bioprinting strategies for regenerating soft tissues in the central nervous system.
Paper-like feel, high contrast, and ultralow power consumption feature prominently in electrophoretic displays and are widely used in electronic readers, tags, blackboards, and other fields. But most of the commercially mature electrophoretic systems remain in black-white pattern and badly need color electrophoresis to meet higher display demands. So, we first modified the integration surface of iron oxide nanoparticle with silica shell and polyethylenimine corona together using an improved one-pot Stöber method, resulting in red electrophoretic particles with a mean size of about 300 nm and a high potential of over +100 mV. By incorporating white nanoparticles, we successfully achieved alternating red-white electrophoretic display with a contrast ratio of 1.54, demonstrating a short response time of 550-1100 ms and a recovery time of 770-1210 ms. It is anticipated to provide a facile reinforcing approach to electrophoretic ink for color electrophoresis.
The circular conversion of agricultural residues into functional materials offers a sustainable strategy to reduce waste, lower carbon footprints, and replace resource-intensive adsorbents. In this study, sugarcane bagasse, an abundant agroindustrial byproduct, was valorized into activated carbons (ACs) through phosphoric acid activation and employed for the decolorization of remelted brown sugar solutions. Characterization by N2 sorption, X-ray photoelectron spectroscopy, and temperature-programmed desorption revealed that oxygen-containing surface functional groups, especially hydroxyl moieties, significantly enhanced colorant removal, whereas carboxylic, lactone, and quinone groups hindered adsorption efficiency. The optimized AC (BAC700) achieved >90% decolorization, surpassing commercial activated carbon and ion-exchange resin despite its moderate surface area. By substituting costly synthetic resins with waste-derived carbons, this approach reduces production costs, environmental impact, and dependence on fossil-based adsorbents. These findings highlight the importance of coupling waste valorization with surface chemistry engineering to advance sustainable separation processes in food production and related industries.
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