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Developing sustainable and efficient catalysts for ammonia synthesis from atmospheric molecular N2 under ambient conditions presents a significant 21st‐century challenge. Two‐dimensional heterostructures, particularly single‐atom catalysts (SACs) supported on two‐dimensional materials, have emerged as a promising avenue due to their remarkable catalytic activity and selectivity. Electrides, characterized by an abundance of free electrons and high surface activity, have attracted substantial attention in this context. Through density functional theory (DFT) calculations, this study proposes electride‐graphene heterostructures (EGHS) as catalysts to effectively regulate charge distribution at the catalytic center, facilitating the optimization of catalytic performance. The EGHS model addresses challenges related to excessive adsorbate binding, mitigating electron transfer compared to electride monolayer adsorption. This novel approach utilizes heterogeneous heterostructures to finely tune the catalytic site, optimizing electron input for enhanced catalysis. Based on the optimized charge transfer for N2 activation, the Cr‐doped EGHS (Cr@EGHS) exhibits a promising performance in the nitrogen reduction reaction, leading to, a relatively low limiting potential of −0.85 V and high selectivity. The hypothesis charge transfer depend on N2 activation is further supported by modulating the distance between component layers of heterostructure. These findings contribute to design principles for 2D heterostructure catalysts and offer a reference for experimental synthesis. [ABSTRACT FROM AUTHOR]

This paper introduces the application of a monitoring system for multi-level lifting of inclined roadway in Tianzhu Coal Mine, and briefly expounds the system structure, working process and innovative application. The application of this system can effectively reduce the hidden danger of equipment in the track transportation of inclined lane and the hidden danger of pedestrians breaking into the rules and regulations during the lifting process, solve the problem of “pedestrians without driving, driving without pedestrians” from the technical level, and provide a good operation and management platform for the safety management of inclined shaft lifting.

Developing advanced hydrogen storage materials with high capacity and efficient reversibility is a crucial aspect for utilizing hydrogen source as a promising alternate to fossil fuels. In this paper, we have systematically investigated the hydrogen storage properties of neutral and negatively charged C9N4 monolayer based on density functional theory (DFT). Our foundings indicate that injecting additional electrons into the adsorbent significantly boosts the adsorption capacity of C9N4 monolayer to H2 molecules. The gravimetric density of negatively charged C9N4 monolayer can reach up to 10.80 wt% when fully covered with hydrogen. Unlike other hydrogen storage methods, the storage and release processes happen automatically upon introducing or removing extra electrons. Moreover, these operations can be easily adjusted through activating or deactivating the charging voltage. As a result, the method is easily reversible and has tunable kinetics without requiring particular activators. Significantly, C9N4 is proved to be a suitable candidate for efficient electron injection/release due to its well electrical conductivity. Our work can serve as a valuable guide in the quest for a novel category of materials for hydrogen storage with high capacity. [ABSTRACT FROM AUTHOR]

Background The value of the widely applied maternal cytomegalovirus (CMV) serological testing approach in predicting intrauterine transmission in highly seroprevalent regions remains unknown. Methods A nested case-control study was conducted based on a maternal-child cohort study. Newborns with congenital CMV (cCMV) infection were included, and each of them was matched to 3 newborns without cCMV infection. Retrospective samples were tested for immunoglobulin G (IgG) avidity and immunoglobulin M (IgM) antibodies in maternal serum and CMV DNA in maternal blood and urine to analyze their associations with cCMV infection. Results Forty-eight newborns with cCMV infection and 144 matched newborns without infection were included in the study. Maternal IgM antibodies and IgG avidity during pregnancy were not statistically associated with intrauterine transmission. The presence of CMV DNAemia indicated a higher risk of cCMV infection, with odds ratio values of 5.7, 6.5, and 13.0 in early, middle, and late pregnancy, respectively. However, the difference in CMV shedding rates in transmitters and nontransmitters was not significant in urine. Conclusions The value of current maternal CMV serological testing in regions with high seropositivity rates is very limited and should be reconsidered. The detection of DNAemia would be helpful in assessing the risk of intrauterine transmission. [ABSTRACT FROM AUTHOR]

Urea is not only a primary fertilizer in modern agriculture but also a crucial raw material for the chemical industry. In the past hundred years, the prevailing industrial synthesis of urea heavily relies on the Bosch–Meiser process to couple NH3 and CO2 under harsh conditions, resulting in high carbon emissions and energy consumption. The conversion of carbon‐ and nitrogen‐containing species into urea through electrochemical reactions under ambient conditions represents a sustainable strategy. Despite the increasing reports on urea electrosynthesis, a comprehensive review that delves into a profound, atomic‐level comprehension of the fundamental reaction mechanisms is currently absent. In this Perspective, recent advancements in electrochemical urea synthesis from CO2/CO and various nitrogenous species (i.e., N2, NOx−, and NO) under ambient conditions are presented, with special emphasis on theoretical understanding of the C─N coupling reaction mechanisms. Several key strategies to facilitate the C─N coupling are then pinpointed, which not only enhance their applicability in practical experiments but also highlight the significant progress achieved in this field. At the end, the major obstacles and potential opportunities in advancing urea electrosynthesis accelerated by theoretical simulations and in situ techniques are discussed. This review is hoped to act as a roadmap to ignite fresh insights and inspiration for the development of electrocatalytic urea synthesis. [ABSTRACT FROM AUTHOR]