The one-step oxidative esterification of methanol and methacrolein to yield methyl methacrylate (MMA) at elevated temperatures and pressures is a crucial chemical procedure for producing MMA. ...However, the conditions under which fire and explosions may occur during this procedure must be determined. This study models gas mixing to predict concentration distribution. Simulation results indicate stability with increasing pressure but wider gradients with higher temperature. Experimental studies on the flammable limits of methanol and methanol/methacrolein vapor mixtures under high temperatures and pressures show that the initial pressure has a significant impact on expanding the explosive limit of flammable vapor, whereas temperature has a relatively minor effect. The combustible limit of the mixed vapor is predicted using the heat balance approach, and a comparison with experimental data shows that the anticipated and real values coincide well.
•The mixing uniformity numerical calculation of methanol and methylacrolein vapor was applied.•The flammability limit of mixed vapor under high temperature and high pressure was determined.•The combustible limit of mixed vapor is predicted by TBM method.
The efficient hydrogen-production through the Aluminum-water reaction has become a prominent subject of interest. The impediment encountered in the reaction can be effectively alleviated by ...Aluminum-based alloy. In this study, density functional theory (DFT) was utilized to explore the mechanism of water decomposition stage on the surface of aluminum and gallium alloy (AGA). Through surface reaction calculations of 12 stable AGA configurations, it was gradually revealed that the optimal alloy ratio was gallium-to-aluminum at 3.5:1. Analysis of the density of states (DOS) indicated that the presence of gallium amplified the activity of surface aluminum. Moreover, frontier orbital theory and charge density maps confirmed that, due to the weak interaction between Ga and ions, the presence of H2 inhibited Ga passivation, thereby enhancing the reactivity of AGA. This paper provided valuable insights into the surface reaction mechanisms of AGA using DFT, offering theoretical support for hydrogen production processes.
•Density functional theory investigated the early stages of AGA-water reaction.•Modeling AGA (Ga proportions 73.8%–81.2%) yields 12 stable configurations.•Ga:Al = 3.5:1 exhibits highest energies for O2, H2O, and co-adsorption.•Ga enhances AGA's catalytic activity, shown in DOS graphs comparisons.•AGA plays dual roles in surface hydrogen dynamics.
Porous materials have received extensive attention due to their superior adsorption properties, but there are few studies on oil adsorption. In this paper, a new self-design high-temperature reactor ...carried out MCC adsorption experiments, and a complete test system was used to study the adsorption characteristics, pyrolysis kinetics and pyrolysis products. The results of SEM and XRD showed that G3H gradually wetted the surface of MCC and the crystallinity increased. In addition, the pyrolysis parameters of MCC-adsorption-G3H (MAG) were measured by DSC and STA. The results showed that MCC was pyrolyzed in one step while MAG was in two. Meanwhile, thermodynamic model fitting indicated that the first stage was Fn and the second was Cnm autocatalytic. Notably, the variation of pyrolysis activation energy in the first stage was similar to that of adsorption capacity. Pyrolysis products of G3H were measured by Py-GC-MS, and pyrolysis residues of MAG were tested by FTIR. Combined with the volatiles determined by TG-IR, the influence of G3H on the pyrolysis characteristics was obtained, and the pyrolysis path of MAG was summarized. The results showed that porous materials can recycle oil and provided a guideline for industrial production.
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•G3H increases pyrolysis rate to 97.13%.•MAG’s main pyrolysis kinetic model is Cnm.•G3H advance synthesis of pyrolysis products.
Microfluidic chips have shown their potential for applications in fields such as chemistry and biology, and 3D printing is increasingly utilized as the fabrication method for microfluidic chips. To ...address key issues such as the long printing time for conventional 3D printing of a single chip and the demand for rapid response in individualized microfluidic chip customization, we have optimized the use of DLP (digital light processing) technology, which offers faster printing speeds due to its surface exposure method. In this study, we specifically focused on developing a fast-manufacturing process for directly printing microfluidic chips, addressing the high cost of traditional microfabrication processes and the lengthy production times associated with other 3D printing methods for microfluidic chips. Based on the designed three-dimensional chip model, we utilized a DLP-based printer to directly print two-dimensional and three-dimensional microfluidic chips with photosensitive resin. To overcome the challenge of clogging in printing microchannels, we proposed a printing method that combined an open-channel design with transparent adhesive tape sealing. This method enables the rapid printing of microfluidic chips with complex and intricate microstructures. This research provides a crucial foundation for the development of microfluidic chips in biomedical research.
The inadequacy of conventional surgical techniques for wound closure and repair in soft and resilient tissues may lead to poor healing outcomes such as local tissue fibrosis and contracture. ...Therefore, the development of adhesive and resilient hydrogels that can adhere firmly to irregular and dynamic wound interfaces and provide a “tension-free proximity” environment for tissue regeneration has become extremely important. Herein, we describe an integrated modeling-experiment-application strategy for engineering a promising hydrogel-based bioadhesive based on recombinant human collagen (RHC) and catechol-modified hyaluronic acid (HA-Cat). Molecular modeling and simulations were used to verify and explore the hypothesis that RHC and HA-Cat can form an assembly complex through physical interactions. The complex was synergistically crosslinked via a catechol/o-quinone coupling reaction and a carbodiimide coupling reactions, resulting in superior hydrogels with strong adhesion and resilience properties. The application of this bioadhesive to tissue adhesion and wound sealing in vivo was successfully demonstrated, with an optimum collagen index, epidermal thickness, and lowest scar width. Furthermore, subcutaneous implantation demonstrated that the bioadhesive exhibited good biocompatibility and degradability. This newly developed hydrogel may be a highly promising surgical adhesive for medical applications, including wound closure and repair.
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•Tenogenic patch can promote the tendon-like morphology, adhesion, proliferation and migration of tendon fibroblasts in vitro.•The tenogenic patch enhanced the collagen fiber ...regeneration in the acute rotator cuff tear model.•The patch scaffold can strengthen tendon and the regeneration of tendon-to-bone insertion.
Rotator cuff tear of shoulder is a common tendon injury. Current therapeutic strategies are unsatisfactory because of poor biomechanical properties of the repaired rotator cuff tendons. To solve this problem, a newly biofabricated tenogenic patch by uniaxial cold-drawing technology was applied for the treatment of acute rotator cuff tear and its therapeutic effects were evaluated in vitro and in vivo. The cytocompatibility results indicated that the engineered patch was capable of promoting the spreading, migration and proliferation of tendon fibroblasts in vitro. Stress–strain curves of the sutured patch indicated improved elasticity followed by the yield phenomena, nonlinear plasticity and obviously delaminated rupture. The tenogenic patch also showed significantly enhanced collagen I deposition and better tendon-to-bone healing in the rat rotator cuff tear models in vivo. Furthermore, implantation with the tenogenic patch also promoted the fibrocartilage formation in Safranin-O/Fast green-staining. The analysis of biomechanical properties showed that the tenogenic patch is capable of improving the ultimate load of the repaired tendon. Therefore, the tenogenic patch may constitute an efficient strategy to enhance tendon-to-bone healing for clinical repair applications of rotator cuff tear.
Antarctic krill proteins (AKPs) were successfully succinylated by using succinic anhydride, and the physicochemical and functional properties of the succinylated proteins as well as their ability to ...protect active curcumin were investigated. The results showed that the succinylation reaction decreased the particle size and hydrophobicity but increased the surface charge of AKPs, which greatly improved the solubility and emulsification of the proteins. On this basis, the succinylated AKPs presented an excellent ability to encapsulate curcumin to prepare emulsions and endowed the emulsions with good physical performance to resist the stress of photothermal treatment, salt and different temperatures. Notably, the succinylated proteins protected encapsulated curcumin from degradation more effectively than the reported protein-phenolic conjugates of carboxymethyl dextrin (CMD)-curcumin and zein-curcumin. These findings indicate that the succinylated AKPs are a promising food resource and present great potential for application in the food industry.
•Antarctic krill proteins were covalently modified via succinylation reaction.•The solubility and emulsifying ability of the succinylated proteins were improved.•The succinylated proteins-stabilized emulsions presented an excellent stability.•The succinylated proteins endowed the emulsions with good resistance to stress.•The succinylated proteins effectively protected the curcumin from being degraded.
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•Nanosecond laser etching crafts micro-nano superhydrophobic surface on 304 stainless steel.•Unique multi-scale, multi-level, and layered features enhance durability and wetting ...performance.•Constructed surface exhibits strong hydrophilic properties, withstanding wear beyond 6 m.•Improved mechanical durability compared to previous superwetted surfaces.
This paper aims to utilize a nanosecond laser and a two-step laser etching method on a 304 stainless steel plate to construct a multi-scale hierarchical composite micro-nano superhydrophilic surface. This surface combines various characteristics such as micro-nano, multi-scale, layered, and multi-level features. By creating this unique surface microstructure, we can alter the surface morphology and roughness to further enhance the mechanical durability and wetting performance of the superhydrophilic stainless steel surface. Through this approach, the constructed surface exhibits strong hydrophilic properties and can withstand wear for distances up to and beyond 6 m.
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•Nanosecond lasers create micro/nano-structures on stainless steel, enabling superwetting for efficient water collection.•Adjusting laser parameters enables rapid water droplet ...spreading (0.2 s) for superhydrophilic surface creation.•Superhydrophilic surface modified with lauric acid achieves superhydrophobicity, with a 159° contact angle and 1° sliding angle.•Triangular pattern with 111° tip angle enhances water collection by 144%, ideal for water-scarce fog environments.
This study demonstrates the effectiveness of nanosecond pulsed laser technology in creating micro/nano-structures on stainless steel surfaces to produce superwetting properties, which can enhance water collection. By tuning laser parameters, a superhydrophilic surface was initially formed on stainless steel, enabling water droplets to spread entirely within 0.2 s. The surface was subsequently modified using lauric acid to achieve superhydrophobic characteristics, exhibiting a 159° contact angle and a 1° sliding angle. Water collection tests revealed that the superhydrophobic surface outperformed the original one, collecting 0.3922 g of water, an 86.76% improvement. Further optimization by introducing non-uniform wetting patterns led to even better results, with the triangular design featuring a 111° tip angle yielding the highest collection weight of 0.5129 g – a 144% increase compared to the unaltered surface. This efficient and convenient method holds promise for fog-based water collection in regions facing water scarcity.
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