The seriousness of the energy crisis and the environmental impact of global anthropogenic activities have led to an urgent need to develop efficient and green fuels. Hydrogen, as a promising ...alternative resource that is produced in an environmentally friendly and sustainable manner by a water splitting reaction, has attracted extensive attention in recent years. However, the large‐scale application of water splitting devices is hindered predominantly by the sluggish oxygen evolution reaction (OER) at the anode. Therefore, the design and exploration of high‐performing OER electrocatalysts is a critical objective. Considering their low prices, abundant reserves, and intrinsic activities, NiFe‐based bimetal compounds are widely studied as excellent OER electrocatalysts. Moreover, recent progress on NiFe‐based OER electrocatalysts in alkaline environments is comprehensively and systematically introduced through various catalyst families including NiFe‐layered hydroxides, metal–organic frameworks, NiFe‐based (oxy)hydroxides, NiFe‐based oxides, NiFe alloys, and NiFe‐based nonoxides. This review briefly introduces the advanced NiFe‐based OER materials and their corresponding reaction mechanisms. Finally, the challenges inherent to and possible strategies for producing extraordinary NiFe‐based electrocatalysts are discussed.
This review briefly introduces the advanced NiFe‐based oxygen evolution reaction (OER) materials and their corresponding reaction mechanisms. After providing this background, recent progress on NiFe‐based OER electrocatalysts through various catalyst families is comprehensively and systematically presented, and the inherent challenges and probable strategies for producing extraordinary NiFe‐based electrocatalysts are finally discussed.
Given that more than two thirds of all energy is lost, mostly as waste heat, in utilization processes worldwide, thermoelectric materials, which can directly convert waste heat to electricity, ...provide an alternative option for optimizing energy utilization processes. After the prediction that superlattices may show high thermoelectric performance, various methods based on quantum effects and superlattice theory have been adopted to analyze bulk materials, leading to the rapid development of thermoelectric materials. Bulk materials with two‐dimensional (2D) structures show outstanding properties, and their high performance originates from both their low thermal conductivity and high Seebeck coefficient due to their strong anisotropic features. Here, the advantages of superlattices for enhancing the thermoelectric performance, the transport mechanism in bulk materials with 2D structures, and optimization methods are discussed. The phenomenological transport mechanism in these materials indicates that thermal conductivities are reduced in 2D materials with intrinsically short mean free paths. Recent progress in the transport mechanisms of Bi2Te3‐, SnSe‐, and BiCuSeO‐based systems is summarized. Finally, possible research directions to enhance the thermoelectric performance of bulk materials with 2D structures are briefly considered.
Thermoelectric bulk materials with 2D structures possess natural structures similar to artificial superlattices, hence enabling the utilization of enhancement methods for superlattices. General optimization methods for Bi2Te3 are reviewed; meanwhile, the progress of advanced research into SnSe and BiCuSeO as promising thermoelectric materials is summarized.
High‐dielectric solvents were explored for enhancing the sulfur utilization in lithium–sulfur (Li−S) batteries, but their applications have been impeded by low stability at the lithium metal anode. ...Now a radical‐directed, lithium‐compatible, and strongly polysulfide‐solvating high‐dielectric electrolyte based on tetramethylurea is presented. Over 200 hours of cycling was realized in Li|Li symmetric cells, showing good compatibility of the tetramethylurea‐based electrolyte with lithium metal. The high solubility of short‐chain polysulfides, as well as the presence of active S3.− radicals, enabled pouch cells to deliver a discharge capacity of 1524 mAh g−1 and an energy density of 324 Wh kg−1. This finding suggests an alternative recipe to ether‐based electrolytes for Li−S batteries.
Li−S batteries: A lithium‐compatible and strongly polysulfide‐solvating high‐dielectric electrolyte based on tetramethylurea was proposed to direct a solvation‐mediated radical reaction pathway. It enables Li−S pouch cells to deliver an energy density of 324 Wh kg−1. Key: red=electrochemical, black=chemical, dashed=diffusion/precipitation.
Esophageal squamous cell carcinoma (ESCC) is one of the deadliest cancers. We performed exome sequencing on 113 tumor-normal pairs, yielding a mean of 82 non-silent mutations per tumor, and 8 cell ...lines. The mutational profile of ESCC closely resembles those of squamous cell carcinomas of other tissues but differs from that of esophageal adenocarcinoma. Genes involved in cell cycle and apoptosis regulation were mutated in 99% of cases by somatic alterations of TP53 (93%), CCND1 (33%), CDKN2A (20%), NFE2L2 (10%) and RB1 (9%). Histone modifier genes were frequently mutated, including KMT2D (also called MLL2; 19%), KMT2C (MLL3; 6%), KDM6A (7%), EP300 (10%) and CREBBP (6%). EP300 mutations were associated with poor survival. The Hippo and Notch pathways were dysregulated by mutations in FAT1, FAT2, FAT3 or FAT4 (27%) or AJUBA (JUB; 7%) and NOTCH1, NOTCH2 or NOTCH3 (22%) or FBXW7 (5%), respectively. These results define the mutational landscape of ESCC and highlight mutations in epigenetic modulators with prognostic and potentially therapeutic implications.
Chromophores that exhibit aggregation‐induced emission (i.e., aggregation‐induced emission luminogens AIEgens) emit intense fluorescence in their aggregated states, but show negligible emission as ...discrete molecular species in solution due to the changes in restriction and freedom of intramolecular motions. As solvent‐swollen quasi‐solids with both a compact phase and a free space, gels enable manipulation of intramolecular motions. Thus, AIE‐active gels have attracted significant interest owing to their various distinctive properties and promising application potential. Herein, a comprehensive overview of AIE‐active gels is provided. The fabrication strategies employed are detailed, and the applications of AIEgens are summarized. In addition, the gel functions arising from the AIE moieties are revealed, along with their structure–property relationships. Furthermore, the applications of AIE‐active gels in diverse areas are illustrated. Finally, ongoing challenges and potential means to address them are discussed, along with future perspectives on AIE‐active gels, with the overall aim of inspiring research on novel materials and ideas.
As emerging luminescent materials, aggregation‐induced‐emission (AIE)‐active (AIE‐active) gels integrate the characteristics of AIE with those of gels, which impart them with various distinctive and advantageous properties in addition to promising application potential. An overview of the progress of AIE‐active gels in terms of their fabrication, functions, and applications is provided.
The objective of this study was to investigate the effects of trimetazidine (TMZ) and coenzyme Q10 (CoQ10) on cisplatin-induced cardiotoxicity in rat cardiomyocytes.
Rat cardiomyocytes were isolated ...and subjected to cisplatin (200 μM) treatment with and without TMZ (200 μM) and CoQ10 (200 mg/L) pretreatment. The cell viability, apoptosis, oxidant and antioxidant indicators, and mitochondrial dysfunction were examined.
TMZ or CoQ10 significantly attenuated cisplatin-induced cell viability inhibition (p<0.01) and apoptosis (p<0.001), and the combined use of TMZ and CoQ10 pretreatment exerted a pronounced effect compared to the effects of using each of these agents individually (p<0.05). TMZ or CoQ10 inhibited the levels of reactive oxidative species (ROS, p<0.01) and malondialdehyde (MDA, p<0.001 and p<0.01, respectively), elevated the activities of antioxidant enzymes superoxide dismutase (SOD, p<0.01) and catalase (CAT, p<0.01 and p<0.05, respectively), evidently enhanced nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2, p<0.05), alleviated mitochondrial membrane potential (ΔΨm) loss (p<0.05), and down-regulated the release of cytochrome c (cyto-c) into the cytosol (p<0.01) in cisplatin-treated cells. The combined use of TMZ and CoQ10 treatment was more effective than using either agent alone (p<0.01 for ROS, MDA, CAT, and cytosolic cyto-c; p<0.05 for SOD, nuclear Nrf2, and ΔΨm loss).
TMZ and CoQ10 showed protective effects against cisplatin-induced cardiotoxicity via attenuating oxidative stress.
There has been a renaissance of interest in exploring highly efficient thermoelectric materials as a possible route to address the worldwide energy generation, utilization, and management. This ...review describes the recent advances in designing high-performance bulk thermoelectric materials. We begin with the fundamental stratagem of achieving the greatest thermoelectric figure of merit ZT of a given material by carrier concentration engineering, including Fermi level regulation and optimum carrier density stabilization. We proceed to discuss ways of maximizing ZT at a constant doping level, such as increase of band degeneracy (crystal structure symmetry, band convergence), enhancement of band effective mass (resonant levels, band flattening), improvement of carrier mobility (modulation doping, texturing), and decrease of lattice thermal conductivity (synergistic alloying, second-phase nanostructuring, mesostructuring, and all-length-scale hierarchical architectures). We then highlight the decoupling of the electron and phonon transport through coherent interface, matrix/precipitate electronic bands alignment, and compositionally alloyed nanostructures. Finally, recent discoveries of new compounds with intrinsically low thermal conductivity are summarized, where SnSe, BiCuSeO, MgAgSb, complex copper and bismuth chalcogenides, pnicogen-group chalcogenides with lone-pair electrons, and tetrahedrites are given particular emphasis. Future possible strategies for further enhancing ZT are considered at the end of this review.
Evapotranspiration (ET) is one of the key variables in the water and energy exchange between land surface and atmosphere. This paper develops an end-member-based two-source approach for estimating ...land surface ET (i.e., the ESVEP model) from remote sensing data, considering the differing responses of soil water content at the upper surface layer to soil evaporation and at the deeper root zone layer to vegetation transpiration. The ESVEP model first diverges the soil-vegetation system net radiation into soil and vegetation components by considering the transmission of direct and diffuse shortwave radiation separately from the transmission of longwave radiation through the canopy, then calculates the four dry/wet soil/vegetation end-members with the diverged soil and vegetation net radiations, and last separates soil evaporation from vegetation transpiration based on the two-phase ET dynamics and the four end-member temperatures. The model can overall produce reasonably good surface energy fluxes and is no more sensitive to meteorology, vegetation, and remote sensing inputs than other two-source energy balance models and surface temperature versus vegetation index (T_{R} -VI) trapezoid models. A reasonable agreement could be found with a small bias of ±8 W/\text{m}^{2} and a root-mean-square error within 60 W/\text{m}^{2} (comparable to accuracies published in other studies) when both model-estimated sensible heat flux and latent heat flux from MODIS remote sensing data are validated with ground-based large aperture scintillometer measurements.
The development of efficient and sustainable methods to access saturated N‐heterocycles is of great importance because of the prevalence of these structures in natural products and bioactive ...compounds. Pd‐catalyzed aza‐Wacker type cyclization is a powerful method and provides access to N‐heterocycles bearing an alkene moiety available for further synthetic manipulations from readily available materials. Herein we disclose a catalyst‐ and reagent‐free formal aza‐Wacker type cyclization reaction for the synthesis of functionalized saturated N‐heterocycles. Key to the success is to conduct the reactions in a continuous‐flow electrochemical reactor without adding supporting electrolyte or additives. The reactions are characterized by broad tolerance of di‐, tri‐ and tetrasubstituted alkenes.
A continuous‐flow electrochemical aza‐Wacker‐type cyclization reaction that is free of catalyst, oxidant, supporting electrolyte, and additives is presented. The method is scalable and compatible with di‐, tri‐, and tetrasubstituted alkenes.
Thermoelectric materials offer an alternative opportunity to tackle the energy crisis and environmental problems by enabling the direct solid-state energy conversion. As a promising candidate with ...full potentials for the next generation thermoelectrics, tin selenide (SnSe) and its associated thermoelectric materials have been attracted extensive attentions due to their ultralow thermal conductivity and high electrical transport performance (power factor). To provide a thorough overview of recent advances in SnSe-based thermoelectric materials that have been revealed as promising thermoelectric materials since 2014, here, we first focus on the inherent relationship between the structural characteristics and the supreme thermoelectric performance of SnSe, including the thermodynamics, crystal structures, and electronic structures. The effects of phonon scattering, pressure or strain, and oxidation behavior on the thermoelectric performance of SnSe are discussed in detail. Besides, we summarize the current theoretical calculations to predict and understand the thermoelectric performance of SnSe, and provide a comprehensive summary on the current synthesis, characterization, and thermoelectric performance of both SnSe crystals and polycrystals, and their associated materials. In the end, we point out the controversies, challenges and strategies toward future enhancements of the SnSe thermoelectric materials.
PDF
