Search

This study focuses on the preparation of Mo0.5VNbTiCr0.25 refractory high-entropy alloy (RHEA) coatings on the surface of Zr-4 alloy using laser cladding technology. The coated samples underwent 24-h aging heat treatment at temperatures of 600 °C, 800 °C, and 1000 °C, as well as laser remelting. The crystal structure, microstructure, microhardness, and wear resistance of each RHEA coating sample were comprehensively analyzed using X-ray diffraction (XRD), scanning electron microscopy (SEM), electron backscattering diffraction (EBSD), Vickers hardness test, and general-purpose friction and wear test. The different effects of aging heat treatment and laser remelting treatment on the microstructure and properties of Mo0.5VNbTiCr0.25 RHEA coatings were investigated. The results showed that each group of RHEA coating samples had good metallurgical bonding with the substrate without obvious defects such as pores and cracks. The coated samples were mainly composed of body-centered cubic (BCC) phases and a small amount of hexagonal close-packed (HCP) phases. The mechanical properties of the laser remelted samples were the best, with a microhardness value of 526 HV0.2, and the best wear resistance. The wear mechanisms included adhesive wear, oxidative wear, and creep wear. [ABSTRACT FROM AUTHOR]

5-Hydroxymethylfurfural (HMF), serving as a versatile platform compound bridging biomass resource and the fine chemicals industry, holds significant importance in biomass conversion processes. The electrooxidation of HMF plays a crucial role in yielding the valuable product (2,5-furandicarboxylic acid), which finds important applications in antimicrobial agents, pharmaceutical intermediates, polyester synthesis, and so on. Defect engineering stands as one of the most effective strategies for precisely synthesizing electrocatalytic materials, which could tune the electronic structure and coordination environment, and further altering the adsorption energy of HMF intermediate species, consequently increasing the kinetics of HMF electrooxidation. Thereinto, the most routine and effective defect are the anionic vacancies and cationic vacancies. In this concise review, the catalytic reaction mechanism for selective HMF oxidation is first elucidated, with a focus on the synthesis strategies involving both anionic and cationic vacancies. Recent advancements in various catalytic oxidation systems for HMF are summarized and synthesized from this perspective. Finally, the future research prospects for selective HMF oxidation are discussed. [ABSTRACT FROM AUTHOR]

Electrocatalytic oxidation of alcohols using heterogeneous catalysts is a promising aqueous, energy-efficient and environmentally friendly approach, especially for coupling different alcohols to prolong the carbon chain via co-oxidation. Precisely regulating critical steps to tailor electrode materials and electrolyte composition is key to selectively coupling alcohols for targeted synthesis. However, selectively coupling different alcohols remains challenging due to the lack of effective catalyst and electrolyte design promoting specific pathways. Herein, we demonstrate a paired electrolysis strategy for combining anodic oxidative coupling of ethanol (EtOH) and benzyl alcohol (PhCH2OH) to synthesize cinnamaldehyde (CAL) and cathodic ammonia production. The strategies involve: (i) utilizing the salt-out effect to balance selective oxidation and coupling rates; (ii) developing platinum-loaded nickel hydroxide electrocatalysts to accelerate intermediate coupling kinetics; (iii) introducing thermodynamically favorable nitrate reduction at the cathode to improve coupling selectivity by avoiding hydrogenation of products while generating valuable ammonia instead of hydrogen. We achieved 85% coupling selectivity and 278 μmol/h NH3 productive rate at 100 mA/cm2 with a low energy input (∼1.63 V). The membrane-free, low energy, scalable approach with a wide substrate scope highlights promising applications of this methodology. This work advances heterogeneous electrocatalytic synthesis through rational design principles that integrate anodic oxidative coupling with cathodic nitrate reduction reactions, having synergistic effects on efficiency and selectivity. [ABSTRACT FROM AUTHOR]

Transgenic ruminants are a valuable resource for both animal breeding and biomedical research. The development of transgenic breeding is proceeding slowly, because it suffers from low efficiency of gene transfer and possible safety problems from uncontrolled random integration. However, new breeding methods combined with genome editing and somatic cell nuclear transfer or microinjection can offer an economic and efficient way to produce gene-edited ruminants, which can serve as bioreactors or have improved disease resistance, animal welfare and product quality. Recent advances in precise genome editing technologies, especially clustered regularly interspaced short palindromic repeat (CRISPR)/Cas9 nucleases, are enabling the systematic development of gene-edited ruminant production. This review covers the development of gene-edited ruminants, the particulars of site-specific engineered nucleases and the state of the art and new insights into practical applications and social acceptance of genome editing technology in ruminants. It is concluded that the production of gene-edited ruminants is feasible and through improvements in genome editing technology it is possible to help feed the world.

Hypoxia‐associated radioresistance in rectal cancer (RC) has severely hampered the response to radioimmunotherapy (iRT), necessitating innovative strategies to enhance RC radiosensitivity and improve iRT efficacy. Here, a catalytic radiosensitizer, DMPtNPS, and a STING agonist, cGAMP, are integrated to overcome RC radioresistance and enhance iRT. DMPtNPS promotes efficient X‐ray energy transfer to generate reactive oxygen species, while alleviating hypoxia within tumors, thereby increasing radiosensitivity. Mechanistically, the transcriptomic and immunoassay analysis reveal that the combination of DMPtNPS and RT provokes bidirectional regulatory effects on the immune response, which may potentially reduce the antitumor efficacy. To mitigate this, cGAMP is loaded into DMPtNPS to reverse the negative impact of DMPtNPS and RT on the tumor immune microenvironment (TiME) through the type I interferon‐dependent pathway, which promotes cancer immunotherapy. In a bilateral tumor model, the combination treatment of RT, DMPtNPS@cGAMP, and αPD‐1 demonstrates a durable complete response at the primary site and enhanced abscopal effect at the distant site. This study highlights the critical role of incorporating catalytic radiosensitizers and STING agonists into the iRT approach for RC. [ABSTRACT FROM AUTHOR]