As emerging two-dimensional(2D)materials,carbides and nitrides(MXenes)could be solid solutions or organized structures made up of multi-atomic layers.With remarkable and adjustable electrical,optical,mechanical,and el...As emerging two-dimensional(2D)materials,carbides and nitrides(MXenes)could be solid solutions or organized structures made up of multi-atomic layers.With remarkable and adjustable electrical,optical,mechanical,and electrochemical characteristics,MXenes have shown great potential in brain-inspired neuromorphic computing electronics,including neuromorphic gas sensors,pressure sensors and photodetectors.This paper provides a forward-looking review of the research progress regarding MXenes in the neuromorphic sensing domain and discussed the critical challenges that need to be resolved.Key bottlenecks such as insufficient long-term stability under environmental exposure,high costs,scalability limitations in large-scale production,and mechanical mismatch in wearable integration hinder their practical deployment.Furthermore,unresolved issues like interfacial compatibility in heterostructures and energy inefficiency in neu-romorphic signal conversion demand urgent attention.The review offers insights into future research directions enhance the fundamental understanding of MXene properties and promote further integration into neuromorphic computing applications through the convergence with various emerging technologies.展开更多
CdS photocatalysts have broad application prospects in environmental purification,energy conversion,and organic synthesis.However,their practical use is often hindered by the rapid recombination of photo-generated ele...CdS photocatalysts have broad application prospects in environmental purification,energy conversion,and organic synthesis.However,their practical use is often hindered by the rapid recombination of photo-generated electron-hole pairs,which limits their efficiency on various reactions.Controlling morphological structures and crystal facets engineering are effective methods to enhance the photocatalytic performance of CdS.In this work,two different forms of CdS photocatalysts were synthesized by a hydrothermal method,namely nanoflower-shaped (CdS-NF) and nanorod-shaped (CdS-NR) for hydrogen peroxide (H_(2)O_(2)) production.The exposed crystal planes of CdS-NF are mainly (0 0 2) planes,while the accesible crystal planes of CdS-NR are notablly (1 0 1) planes.Notably,the photocatalytic hydrogen peroxide production yield of CdS-NR was high at 1225.13 μmol·h^(−1)·g^(−1),which is 1.78 times higher than the H_(2)O_(2) generation rate of CdS-NF.Moreover,through free radical capture experiments and DFT calculations,the reaction pathway was further explored.Both different configurations of cadmium sulfide based photocatalysts conform to the reaction mechanism of oxygen reduction as the main and water oxidation as the auxiliary.展开更多
Avian cognitive abilities rival those of primates.These capacities have been linked to high pallial neuronal density and prefrontal cortex-like dorsal ventricular ridge(DVR)circuitry.Although the DVR is now recognized...Avian cognitive abilities rival those of primates.These capacities have been linked to high pallial neuronal density and prefrontal cortex-like dorsal ventricular ridge(DVR)circuitry.Although the DVR is now recognized as a pallial structure homologous to the mammalian cortex,its morphological basis remains unclear.Here,we combine Nissl staining,Golgi-Cox labeling,and 3D reconstruction to map neuronal morphology across five telencephalic regions in the Rock Pigeon(Columba livia).From 64 fully reconstructed neurons,we quantified dendritic field area,total dendritic length,branching architecture,and radial arbor organization.DVR neurons showed the largest dendritic fields and the highest branching complexity.Single-nucleus transcriptomic data further revealed that the Nidopallium Caudolaterale(NCL),the core DVR subregion,expresses a neuronmorphogenesis gene module whose activity correlates with dendritic field size.Together,these results identify a molecular and morphological signature of DVR neurons and highlight the computational significance of Nidopallium Caudolaterale.This work provides an integrated comparison of telencephalic neuronal morphology and gene expression in birds.展开更多
While microwave(MW)discharge technology has been developed to address the challenges inherent in shar-pening metal-bonded diamond grinding wheels(MD-GW),the surface morphology and grinding performance characteristics ...While microwave(MW)discharge technology has been developed to address the challenges inherent in shar-pening metal-bonded diamond grinding wheels(MD-GW),the surface morphology and grinding performance characteristics of wheels processed through this method remain insufficiently characterized and warrant further investigation.This study employed an in-situ experimental setup to analyze MD-GW sharpened through MW discharge,with a focus on abrasive damage,grit protrusion height and uniformity,the number of effective abrasives,chip space,and bond morphology.The grinding performance of MW-sharpened MD-GW was assessed based on dynamic grinding ratios and surface quality in zirconia grinding experiments,using mechanical sharpening as the comparison group.The results revealed that MW sharpening enhanced abrasive integrity when compared to mechanical methods,albeit with minor graphitization and localized oxidative damage occurring.Furthermore,after being sharpened by the MW method,the grit protrusion height increased,demonstrating good uniformity,and simultaneously exhibiting a higher number of effective abrasives.Noticeable craters formed in proximity to the abrasives,augmenting chip space,but sputtering led to the formation of metal deposition layers on the abrasive surfaces.The MW-sharpened wheel exhibited superior grinding wear ratios,with dynamic grinding ratios initially increasing and subsequently decreasing as the grinding process pro-gressed.These enhancements in surface morphology allowed the MW-sharpened MD-GW to remove zirconia ceramics in a ductile manner,resulting in improved grinding surface quality.The importance of this study lies in the development of an innovative sharpening technique that improved the surface morphology quality of MD-GW,with potential ramifications for enhancing the efficiency and quality of grinding difficult-to-machine materials.展开更多
The morphology and heterojunction engineering are effective ways to boost the performance of Cubased catalysts. Herein, we have reported the designed synthesis of two-dimensional Cu-Cu O heterojunction nanosheets(2D C...The morphology and heterojunction engineering are effective ways to boost the performance of Cubased catalysts. Herein, we have reported the designed synthesis of two-dimensional Cu-Cu O heterojunction nanosheets(2D Cu-Cu O NS) based on 3-aminopropyl-triethoxysilane(APTES, KH550) aided synthetic strategy. The APTES can act as both the ligand and alkali(-OH) source to guide the large-scale synthesis of 2D Cu-based precursor, which can transform into 2D Cu-Cu O NS by the controllable post-treatment.The Si species from APTES can protect the particles from the severe aggregation and growth, guaranteeing the formation of 2D sheets composed of small-sized Cu-Cu O heterojunction(about 20 nm). The heterojunction interfaces can provide plentiful active sites to boost the catalytic ability. The 2D sheets can provide large accessible surface, being conducive to the contact of the catalyst and reactants. Benefiting from above virtues, the 2D Cu-Cu O NS showed the superior catalytic performance for the reduction of a series of nitro compounds, being superior to most reported non-noble metal-based catalysts. Notably,it exhibited good re-cycled performance with no obvious performance degradation after 10 consecutive catalysis. The present study will be promising to promote the application of the Cu-based catalysts, due to its ability to control the morphology and potential for the large-scale synthesis.展开更多
Understanding the morphological dynamics in highly braided rivers,like the Brahmaputra,is crucial for effective river management.To gain this understanding,data is essential for mathematical modeling,enabling short an...Understanding the morphological dynamics in highly braided rivers,like the Brahmaputra,is crucial for effective river management.To gain this understanding,data is essential for mathematical modeling,enabling short and medium-term predictions of morphological changes.Our study focused on the Palasbari-Gumi stretch of the Brahmaputra River,utilizing a two-dimensional morphological model(MIKE-21C).Our objectives were to predict erosion patterns,plan protective measures,and anticipate morphological changes.Author conducted multiple models runs under various hydrological scenarios.For coarse sand,the model projected an annual sediment load of 257 Mt/year in 2021,with a bankfull discharge of 314 Mt/year.Historical records noted 400 Mt/year sediment load in the Brahmaputra.Importantly,our model's predictions closely matched empirical data,especially regarding ADCP velocities,design flood levels,and annual sediment load.Peak model velocities deviated by less than 9%from ADCP measurements,predominantly within acceptable limits.Predicted flood levels for bankfull discharge conditions achieved nearly 96%accuracy at the Gumi site.This study highlights the role of predictive modeling in guiding river training measures,especially in dynamic braided river systems like the Brahmaputra,over a two-3 year horizon.展开更多
The proliferation of wearable biodevices has boosted the development of soft,innovative,and multifunctional materials for human health monitoring.The integration of wearable sensors with intelligent systems is an over...The proliferation of wearable biodevices has boosted the development of soft,innovative,and multifunctional materials for human health monitoring.The integration of wearable sensors with intelligent systems is an overwhelming tendency,providing powerful tools for remote health monitoring and personal health management.Among many candidates,two-dimensional(2D)materials stand out due to several exotic mechanical,electrical,optical,and chemical properties that can be efficiently integrated into atomic-thin films.While previous reviews on 2D materials for biodevices primarily focus on conventional configurations and materials like graphene,the rapid development of new 2D materials with exotic properties has opened up novel applications,particularly in smart interaction and integrated functionalities.This review aims to consolidate recent progress,highlight the unique advantages of 2D materials,and guide future research by discussing existing challenges and opportunities in applying 2D materials for smart wearable biodevices.We begin with an in-depth analysis of the advantages,sensing mechanisms,and potential applications of 2D materials in wearable biodevice fabrication.Following this,we systematically discuss state-of-the-art biodevices based on 2D materials for monitoring various physiological signals within the human body.Special attention is given to showcasing the integration of multi-functionality in 2D smart devices,mainly including self-power supply,integrated diagnosis/treatment,and human–machine interaction.Finally,the review concludes with a concise summary of existing challenges and prospective solutions concerning the utilization of2D materials for advanced biodevices.展开更多
The surface transfer doping model has been extensively adopted as a mechanism to account for the generation of hole accumulation layers below hydrogen-terminated diamond(H-diamond)surfaces.To achieve effective surface...The surface transfer doping model has been extensively adopted as a mechanism to account for the generation of hole accumulation layers below hydrogen-terminated diamond(H-diamond)surfaces.To achieve effective surface transfer doping,surface electron acceptor materials with high electron affinity(EA)are required to produce a high density of two-dimensional hole gas(2DHG)on the H-diamond subsurface.We have established ingenious theoretical models to demonstrate that even if these solid materials do not have a high EA value,they remain capable of absorbing electrons from the H-diamond surface by forming a negatively charged interface to act as a surface electron acceptor in the surface transfer doping model.Our calculations,particularly for the local density of states,provide compelling evidence that the effect of an interface with negative charges induces an upward band bending on the H-diamond side.Furthermore,the valence band maximum of the diamond atoms at the interface crosses the Fermi level,giving rise to strong surface transfer p-type doping.These results give a strong theoretical interpretation of the origin of 2DHG on H-diamond surfaces.The proposed guidelines contribute to further improvements in the performance of 2DHG H-diamond field effect transistors.展开更多
Laser-directed energy deposition(L-DED)is an advanced additive manufacturing technology primarily adopted in metal three-dimensional printing systems.The L-DED process is characterized by various defects,thus necessit...Laser-directed energy deposition(L-DED)is an advanced additive manufacturing technology primarily adopted in metal three-dimensional printing systems.The L-DED process is characterized by various defects,thus necessitating the extensive use of in-situ monitoring to enable real-time adjustments of process parameters by detecting molten-pool features.To address the challenge of accurately extracting the molten-pool morphology from an undetached spatter,an innovative monitoring method based on the U-Net(U-shaped network)is proposed herein.A lightweight architecture accelerates the processing speed,whereas an enhanced loss function incorporating weight maps augments the segmentation precision.The model performance is evaluated by comparing its segmentation accuracy and processing speed with those of the conventional U-Net,using the mean intersection over union(MIoU)as the segmentation metric.The improved model demonstrates superior segmentation accuracy at the interface between the molten pool and spatter,with a peak MIoU of 0.9798 achieved on the test set.Furthermore,this model processes each image in an extremely short time of 17.9 ms.Using this segmentation algorithm,the error in extracting the molten-pool width from single-track experiments is within 0.1 mm.The proposed method for monitoring the molten-pool morphology is suitable for deployment in online monitoring systems,thus providing a foundation for subsequent process-parameter regulation.展开更多
Multicomponent Gd_(1−x)Sm_(x)Ba_(0.5)Sr_(0.5)CoCuO_(5+δ)double perovskites are optimized for application in terms of chemical composi-tion and morphology for the use as oxygen electrodes in solid oxide cells.Structur...Multicomponent Gd_(1−x)Sm_(x)Ba_(0.5)Sr_(0.5)CoCuO_(5+δ)double perovskites are optimized for application in terms of chemical composi-tion and morphology for the use as oxygen electrodes in solid oxide cells.Structural studies of other physicochemical properties are con-ducted on a series of materials obtained by the sol-gel method with different ratios of Gd and Sm cations.It is documented that changing the x value,and the resulting adjustment of the average ionic radius,have a significant impact on the crystal structure,stability,as well as on the total conductivity and thermomechanical properties of the materials,with the best results obtained for the Gd_(0.75)Sm_(0.2)5Ba_(0.5)Sr_(0.5)CoCuO_(5+δ)composition.Oxygen electrodes are prepared using the selected compound,allowing to obtain low polarization resistance values,such as 0.086Ω·cm^(2)at 800℃.Systematic studies of electrocatalytic activity are conducted using La_(0.8)Sr_(0.2)Ga_(0.8)Mg_(_(0.2))O_(3−δ)as the electrolyte for all electrodes,and Ce_(0.8)Gd_(0.2)O_(2−δ)electrolyte for the best performing Gd_(0.75)Sm_(0.2)5Ba_(0.5)Sr_(0.5)CoCuO_(5+δ)electrodes.The electrochemical data are analyzed using the distribution of relaxation times method.Also,the influence of the preparation method of the electrode material is in-ve`stigated using the electrospinning technique.Finally,the performance of the Gd_(0.75)Sm_(0.2)5Ba_(0.5)Sr_(0.5)CoCuO_(5+δ)electrodes is tested in a Ni-YSZ(yttria-stabilized zirconia)anode-supported cell with a Ce_(0.8)Gd_(0.2)O_(2−δ)buffer layer,in the fuel cell and electrolyzer operating modes.With the electrospun electrode,a power density of 462 mW·cm^(−2)is obtained at 700℃,with a current density of ca.0.2 A·cm^(−2)at 1.3 V for the electrolysis at the same temperature,indicating better performance compared to the sol-gel-based electrode.展开更多
Zinc oxide(ZnO)serves as a crucial functional semiconductor with a wide direct bandgap of approximately 3.37 eV.Solvothermal reaction is commonly used in the synthesis of ZnO micro/nanostructures,given its low cost,si...Zinc oxide(ZnO)serves as a crucial functional semiconductor with a wide direct bandgap of approximately 3.37 eV.Solvothermal reaction is commonly used in the synthesis of ZnO micro/nanostructures,given its low cost,simplicity,and easy implementation.Moreover,ZnO morphology engineering has become desirable through the alteration of minor conditions in the reaction process,particularly at room temperature.In this work,ZnO micro/nanostructures were synthesized in a solution by varying the amounts of the ammonia added at low temperatures(including room temperature).The formation of Zn^(2+)complexes by ammonia in the precursor regulated the reaction rate of the morphology engineering of ZnO,which resulted in various structures,such as nanoparticles,nanosheets,microflowers,and single crystals.Finally,the obtained ZnO was used in the optoelectronic application of ultraviolet detectors.展开更多
A macro-tidal tropical estuary with high fluvial discharge is characterized by both fragility and remarkable dynamism.This study utilizes the Salween River Delta(SRD)as a case example to examine the interplay between ...A macro-tidal tropical estuary with high fluvial discharge is characterized by both fragility and remarkable dynamism.This study utilizes the Salween River Delta(SRD)as a case example to examine the interplay between morphology and vegetation under similar tidal conditions.Our analysis of correlations and inferences revealed several significant trends in the SRD:(1)an overall expansion of land area and intertidal vegetation,with the most pronounced changes occurring in the eastern sector;(2)the predominance of river discharge influencing the southwestern and northern sectors,contrasted with the primary impact of storm surges in the eastern sector;and(3)three distinct causal relationships among estuarine morphology,vegetation,storm surges,and river discharge:a direct model where river discharge shapes estuarine morphology,a progressive model in which river discharge affects vegetation distribution,subsequently influencing estuarine morphology,and a hybrid model where storm surges directly impact vegetation and indirectly modify its distribution through changes in estuarine morphology.The stability of sediment supply and the role of intertidal vegetation are crucial for the continuous seaward advance,providing a vital foundation for the protection and development of estuarine deltas.展开更多
Fueled by the increasing imperative for sustainable energy solutions and the burgeoning emphasis on health awareness,self-powered techniques have undergone notable strides in advancement.Triboelectric nanogenerators(T...Fueled by the increasing imperative for sustainable energy solutions and the burgeoning emphasis on health awareness,self-powered techniques have undergone notable strides in advancement.Triboelectric nanogenerators(TENGs)stand out as a prominent device capitalizing on the principles of triboelectrification and electrostatic induction to generate electricity or electrical signals.In efforts to augment the electrical output performance of TENGs and broaden their range of applications,researchers have endeavored to refine materials,surface morphology,and structural design.Among them,physical morphological modifications play a pivotal role in enhancing the electrical properties of TENGs by increasing the contact surface area,which can be achieved by building micro-/nano-structures on the surface or inside the friction material.In this review,we summarize the common morphologies of TENGs,categorize the morphologies into surface and internal structures,and elucidate their roles in enhancing the electric output performance of devices.Moreover,we systematically classify the methodologies employed for morphological preparation into physical and chemical approaches,thereby furnishing a comprehensive survey of the diverse techniques.Subsequently,typical applications of TENGs with special morphology divided by energy harvesting and self-powered sensors are presented.Finally,an overview of the challenges and future trajectories pertinent to TENGs is conducted.Through this endeavor,the aim of this article is to catalyze the evolution of further strategies for enhancing performance of TENGs.展开更多
Morphological alterations in dendritic spines have been linked to changes in functional communication between neurons that affect learning and memory.Kinesin-4 KIF21A helps organize the microtubule-actin network at th...Morphological alterations in dendritic spines have been linked to changes in functional communication between neurons that affect learning and memory.Kinesin-4 KIF21A helps organize the microtubule-actin network at the cell cortex by interacting with KANK1;however,whether KIF21A modulates dendritic structure and function in neurons remains unknown.In this study,we found that KIF21A was distributed in a subset of dendritic spines,and that these KIF21A-positive spines were larger and more structurally plastic than KIF21A-negative spines.Furthermore,the interaction between KIF21A and KANK1 was found to be critical for dendritic spine morphogenesis and synaptic plasticity.Knockdown of either KIF21A or KANK1 inhibited dendritic spine morphogenesis and dendritic branching,and these deficits were fully rescued by coexpressing full-length KIF21A or KANK1,but not by proteins with mutations disrupting direct binding between KIF21A and KANK1 or binding between KANK1 and talin1.Knocking down KIF21A in the hippocampus of rats inhibited the amplitudes of long-term potentiation induced by high-frequency stimulation and negatively impacted the animals’cognitive abilities.Taken together,our findings demonstrate the function of KIF21A in modulating spine morphology and provide insight into its role in synaptic function.展开更多
A functional interlayer based on two-dimensional(2D)porous modified vermiculite nanosheets(PVS)was obtained by acid-etching vermiculite nanosheets.The as-obtained 2D porous nanosheets exhibited a high specific surface...A functional interlayer based on two-dimensional(2D)porous modified vermiculite nanosheets(PVS)was obtained by acid-etching vermiculite nanosheets.The as-obtained 2D porous nanosheets exhibited a high specific surface area of 427 m^(2)·g^(-1)and rich surface active sites,which help restrain polysulfides(LiPSs)through good physi-cal and chemical adsorption,while simultaneously accelerating the nucleation and dissolution kinetics of Li_(2)S,effec-tively suppressing the shuttle effect.The assembled lithium-sulfur batteries(LSBs)employing the PVS-based inter-layer delivered a high initial discharge capacity of 1386 mAh·g^(-1)at 0.1C(167.5 mAh·g^(-1)),long-term cycling stabil-ity,and good rate property.展开更多
This paper investigates ruin,capital injection,and dividends for a two-dimensional risk model.The model posits that surplus levels of insurance companies are governed by a perturbed composite Poisson risk model.This m...This paper investigates ruin,capital injection,and dividends for a two-dimensional risk model.The model posits that surplus levels of insurance companies are governed by a perturbed composite Poisson risk model.This model introduces a dependence between the two surplus levels,present in both the associated perturbations and the claims resulting from common shocks.Critical levels of capital injection and dividends are established for each of the two risks.The surplus levels are observed discretely at fixed intervals,guiding decisions on capital injection,dividends,and ruin at these junctures.This study employs a two-dimensional Fourier cosine series expansion method to approximate the finite time expected discounted operating cost until ruin.The ensuing approximation error is also quantified.The validity and accuracy of the method are corroborated through numerical examples.Furthermore,the research delves into the optimal capital allocation problem.展开更多
Introduction: the left atrial appendage, a dormant embryonic vestige, would play a major role in cardiac hemodynamic changes, volume homeostasis and thrombi formation. It, therefore constitutes a therapeutic target. I...Introduction: the left atrial appendage, a dormant embryonic vestige, would play a major role in cardiac hemodynamic changes, volume homeostasis and thrombi formation. It, therefore constitutes a therapeutic target. Its morphology is extremely variable. Objective: it consisted on determining the morphological variations of the left auricle as well as their interest in the prevention of thrombi in the Senegalese. Material and Method: This study was conducted by dissecting 36 fresh hearts from Senegalese anatomical subjects with a sampling of the left atrial appendage, including specimens with normal morphological appearance. Their morphology was studied using the fresh and frozen plaster molding method. The data obtained were analyzed statistically. Results: the average age of the subjects was 33 years, with a sex ratio of 1.06, the cauliflower shape was dominant with 57% of cases and the cactus shape (4%) was less frequent. The cauliflower shape presented a clear angulation compared to the others without statistically significant differences according to age. Conclusion: This work showed a great morphological variability of the left atrial appendage. It can provide an update on the specificity of Senegalese. Taking these variations into account is important in the safe management of hemodynamic conditions and the improvement of the management of recurrent strokes.展开更多
Lithium-sulfur(Li-S)batteries with high energy density and capacity have garnered significant research attention among various energy storage devices.However,the shuttle effect of polysulfides(LiPSs)remains a major ch...Lithium-sulfur(Li-S)batteries with high energy density and capacity have garnered significant research attention among various energy storage devices.However,the shuttle effect of polysulfides(LiPSs)remains a major challenge for their practical application.The design of battery separators has become a key aspect in addressing the challenge.MXenes,a promising two-dimensional(2D)material,offer exceptional conductivity,large surface area,high mechanical strength,and active sites for surface reactions.When assembled into layered films,MXenes form highly tunable two-dimensional channels ranging from a few angstroms to over 1 nm.These nanoconfined channels are instrumental in facilitating lithium-ion transport while effectively impeding the shuttle effect of LiPSs,which are essential for improving the specific capacity and cyclic stability of Li-S batteries.Substantial progress has been made in developing MXenes-based separators for Li-S batteries,yet there remains a research gap in summarizing advancements from the perspective of interlayer engineering.This entails maintaining the 2D nanochannels of layered MXenes-based separators while modulating the physicochemical environment within the MXenes interlayers through targeted modifications.This review highlights advancements in in situ modification of MXenes and their integration with 0D,1D,and 2D materials to construct laminated nanocomposite separators for Li-S batteries.The future development directions of MXenes-based materials in Li-S energy storage devices are also outlined,to drive further advancements in MXenes for Li-S battery separators.展开更多
The preferential oxidation of CO(CO-PROX)reaction is a cost-effective method for eliminating trace amounts of CO from the fuel H2.Pt-based catalysts have been extensively studied for COPROX,with their activity influen...The preferential oxidation of CO(CO-PROX)reaction is a cost-effective method for eliminating trace amounts of CO from the fuel H2.Pt-based catalysts have been extensively studied for COPROX,with their activity influenced by the morphology of the support.Hydrothermal synthesis was employed to produce different morphologies ofγ-Al_(2)O_(3):flower-likeγ-Al_(2)O_(3)(f)exposing(110)crystal faces,sheet-likeγ-Al_(2)O_(3)(s)revealing(100)crystal faces,and rod-likeγ-Al_(2)O_(3)(r)displaying(111)crystal faces,followed by loading PtCo nanoparticles.The exposed crystal faces of the support impact the alloying degree of the PtCo nanoparticles,and an increase in the alloying degree correlates with enhanced catalyst reactivity.Pt_(3)Co intermetallic compounds were identified onγ-Al_(2)O_(3)(f)exposing(110)crystal faces,and PtCo/γ-Al_(2)O_(3)(f)showed high catalytic activity in the CO-PROX reaction,achieving 100%CO conversion across a broad temperature range of 50−225°C.In contrast,only partial alloying of PtCo was observed onγ-Al_(2)O_(3)(s).Furthermore,no alloying between Pt and Co occurred in PtCo/γ-Al_(2)O_(3)(r),resulting in a reaction rate at 50°C that was merely 11%of that of PtCo/γ-Al_(2)O_(3)(f).The formation of Pt3Co intermetallic compounds led to a more oxidized state of Pt,which significantly diminished the adsorption of CO on Pt and augmented the active oxygen species,thereby facilitating the selective oxidation of CO.展开更多
Titanium dioxide(TiO_(2))has been an important protective ingredient in mineral-based sunscreens since the 1990s.However,traditional TiO_(2)nanoparticle formulations have seen little improvement over the past decades ...Titanium dioxide(TiO_(2))has been an important protective ingredient in mineral-based sunscreens since the 1990s.However,traditional TiO_(2)nanoparticle formulations have seen little improvement over the past decades and continue to face persistent challenges related to light transmission,biosafety,and visual appearance.Here,we report the discovery of two-dimensional(2D)TiO_(2),characterized by a micro-sized lateral dimension(~1.6μm)and atomic-scale thickness,which fundamentally resolves these long-standing issues.The 2D structure enables exceptional light management,achieving 80%visible light transparency—rendering it nearly invisible on the skin—while maintaining UV-blocking performance comparable to unmodified rutile TiO_(2)nanoparticles.Its larger lateral size results in a two-orders-of-magnitude reduction in skin penetration(0.96 w/w%),significantly enhancing biosafety.Moreover,the unique layered architecture inherently suppresses the generation of reactive oxygen species(ROS)under sunlight exposure,reducing the ROS generation rate by 50-fold compared to traditional TiO_(2)nanoparticles.Through precise metal element modulation,we further developed the first customizable sunscreen material capable of tuning UV protection ranges and automatically matching diverse skin tones.The 2D TiO_(2)offers a potentially transformative approach to modern sunscreen formulation,combining superior UV protection,enhanced safety and a natural appearance.展开更多
基金supported by the NSFC(12474071)Natural Science Foundation of Shandong Province(ZR2024YQ051,ZR2025QB50)+6 种基金Guangdong Basic and Applied Basic Research Foundation(2025A1515011191)the Shanghai Sailing Program(23YF1402200,23YF1402400)funded by Basic Research Program of Jiangsu(BK20240424)Open Research Fund of State Key Laboratory of Crystal Materials(KF2406)Taishan Scholar Foundation of Shandong Province(tsqn202408006,tsqn202507058)Young Talent of Lifting engineering for Science and Technology in Shandong,China(SDAST2024QTB002)the Qilu Young Scholar Program of Shandong University。
文摘As emerging two-dimensional(2D)materials,carbides and nitrides(MXenes)could be solid solutions or organized structures made up of multi-atomic layers.With remarkable and adjustable electrical,optical,mechanical,and electrochemical characteristics,MXenes have shown great potential in brain-inspired neuromorphic computing electronics,including neuromorphic gas sensors,pressure sensors and photodetectors.This paper provides a forward-looking review of the research progress regarding MXenes in the neuromorphic sensing domain and discussed the critical challenges that need to be resolved.Key bottlenecks such as insufficient long-term stability under environmental exposure,high costs,scalability limitations in large-scale production,and mechanical mismatch in wearable integration hinder their practical deployment.Furthermore,unresolved issues like interfacial compatibility in heterostructures and energy inefficiency in neu-romorphic signal conversion demand urgent attention.The review offers insights into future research directions enhance the fundamental understanding of MXene properties and promote further integration into neuromorphic computing applications through the convergence with various emerging technologies.
基金support from Natural Science Foundation of Shandong Province(ZR2022MB049,ZR2021MB104)the National Natural Science Foundation of China(22078174).
文摘CdS photocatalysts have broad application prospects in environmental purification,energy conversion,and organic synthesis.However,their practical use is often hindered by the rapid recombination of photo-generated electron-hole pairs,which limits their efficiency on various reactions.Controlling morphological structures and crystal facets engineering are effective methods to enhance the photocatalytic performance of CdS.In this work,two different forms of CdS photocatalysts were synthesized by a hydrothermal method,namely nanoflower-shaped (CdS-NF) and nanorod-shaped (CdS-NR) for hydrogen peroxide (H_(2)O_(2)) production.The exposed crystal planes of CdS-NF are mainly (0 0 2) planes,while the accesible crystal planes of CdS-NR are notablly (1 0 1) planes.Notably,the photocatalytic hydrogen peroxide production yield of CdS-NR was high at 1225.13 μmol·h^(−1)·g^(−1),which is 1.78 times higher than the H_(2)O_(2) generation rate of CdS-NF.Moreover,through free radical capture experiments and DFT calculations,the reaction pathway was further explored.Both different configurations of cadmium sulfide based photocatalysts conform to the reaction mechanism of oxygen reduction as the main and water oxidation as the auxiliary.
基金supported by the National Natural Science Foundation of China(Grant Nos.32170642 and 32370682)。
文摘Avian cognitive abilities rival those of primates.These capacities have been linked to high pallial neuronal density and prefrontal cortex-like dorsal ventricular ridge(DVR)circuitry.Although the DVR is now recognized as a pallial structure homologous to the mammalian cortex,its morphological basis remains unclear.Here,we combine Nissl staining,Golgi-Cox labeling,and 3D reconstruction to map neuronal morphology across five telencephalic regions in the Rock Pigeon(Columba livia).From 64 fully reconstructed neurons,we quantified dendritic field area,total dendritic length,branching architecture,and radial arbor organization.DVR neurons showed the largest dendritic fields and the highest branching complexity.Single-nucleus transcriptomic data further revealed that the Nidopallium Caudolaterale(NCL),the core DVR subregion,expresses a neuronmorphogenesis gene module whose activity correlates with dendritic field size.Together,these results identify a molecular and morphological signature of DVR neurons and highlight the computational significance of Nidopallium Caudolaterale.This work provides an integrated comparison of telencephalic neuronal morphology and gene expression in birds.
基金Supported by Hunan Provincial Natural Science Foundation(Grant Nos.2023JJ60182 and 2025JJ50273)Scientific Research Fund of Hunan Provincial Education Department(Grant Nos.22B0561 and 23C0188)National Natural Science Foundation of China(Grant No.52305465).
文摘While microwave(MW)discharge technology has been developed to address the challenges inherent in shar-pening metal-bonded diamond grinding wheels(MD-GW),the surface morphology and grinding performance characteristics of wheels processed through this method remain insufficiently characterized and warrant further investigation.This study employed an in-situ experimental setup to analyze MD-GW sharpened through MW discharge,with a focus on abrasive damage,grit protrusion height and uniformity,the number of effective abrasives,chip space,and bond morphology.The grinding performance of MW-sharpened MD-GW was assessed based on dynamic grinding ratios and surface quality in zirconia grinding experiments,using mechanical sharpening as the comparison group.The results revealed that MW sharpening enhanced abrasive integrity when compared to mechanical methods,albeit with minor graphitization and localized oxidative damage occurring.Furthermore,after being sharpened by the MW method,the grit protrusion height increased,demonstrating good uniformity,and simultaneously exhibiting a higher number of effective abrasives.Noticeable craters formed in proximity to the abrasives,augmenting chip space,but sputtering led to the formation of metal deposition layers on the abrasive surfaces.The MW-sharpened wheel exhibited superior grinding wear ratios,with dynamic grinding ratios initially increasing and subsequently decreasing as the grinding process pro-gressed.These enhancements in surface morphology allowed the MW-sharpened MD-GW to remove zirconia ceramics in a ductile manner,resulting in improved grinding surface quality.The importance of this study lies in the development of an innovative sharpening technique that improved the surface morphology quality of MD-GW,with potential ramifications for enhancing the efficiency and quality of grinding difficult-to-machine materials.
基金the support of this research by the National Natural Science Foundation of China (No. 91961111)the Natural Science Foundation of Heilongjiang Province (No. ZD2021B003)。
文摘The morphology and heterojunction engineering are effective ways to boost the performance of Cubased catalysts. Herein, we have reported the designed synthesis of two-dimensional Cu-Cu O heterojunction nanosheets(2D Cu-Cu O NS) based on 3-aminopropyl-triethoxysilane(APTES, KH550) aided synthetic strategy. The APTES can act as both the ligand and alkali(-OH) source to guide the large-scale synthesis of 2D Cu-based precursor, which can transform into 2D Cu-Cu O NS by the controllable post-treatment.The Si species from APTES can protect the particles from the severe aggregation and growth, guaranteeing the formation of 2D sheets composed of small-sized Cu-Cu O heterojunction(about 20 nm). The heterojunction interfaces can provide plentiful active sites to boost the catalytic ability. The 2D sheets can provide large accessible surface, being conducive to the contact of the catalyst and reactants. Benefiting from above virtues, the 2D Cu-Cu O NS showed the superior catalytic performance for the reduction of a series of nitro compounds, being superior to most reported non-noble metal-based catalysts. Notably,it exhibited good re-cycled performance with no obvious performance degradation after 10 consecutive catalysis. The present study will be promising to promote the application of the Cu-based catalysts, due to its ability to control the morphology and potential for the large-scale synthesis.
文摘Understanding the morphological dynamics in highly braided rivers,like the Brahmaputra,is crucial for effective river management.To gain this understanding,data is essential for mathematical modeling,enabling short and medium-term predictions of morphological changes.Our study focused on the Palasbari-Gumi stretch of the Brahmaputra River,utilizing a two-dimensional morphological model(MIKE-21C).Our objectives were to predict erosion patterns,plan protective measures,and anticipate morphological changes.Author conducted multiple models runs under various hydrological scenarios.For coarse sand,the model projected an annual sediment load of 257 Mt/year in 2021,with a bankfull discharge of 314 Mt/year.Historical records noted 400 Mt/year sediment load in the Brahmaputra.Importantly,our model's predictions closely matched empirical data,especially regarding ADCP velocities,design flood levels,and annual sediment load.Peak model velocities deviated by less than 9%from ADCP measurements,predominantly within acceptable limits.Predicted flood levels for bankfull discharge conditions achieved nearly 96%accuracy at the Gumi site.This study highlights the role of predictive modeling in guiding river training measures,especially in dynamic braided river systems like the Brahmaputra,over a two-3 year horizon.
基金the support from the National Natural Science Foundation of China(22272004,62272041)the Fundamental Research Funds for the Central Universities(YWF-22-L-1256)+1 种基金the National Key R&D Program of China(2023YFC3402600)the Beijing Institute of Technology Research Fund Program for Young Scholars(No.1870011182126)。
文摘The proliferation of wearable biodevices has boosted the development of soft,innovative,and multifunctional materials for human health monitoring.The integration of wearable sensors with intelligent systems is an overwhelming tendency,providing powerful tools for remote health monitoring and personal health management.Among many candidates,two-dimensional(2D)materials stand out due to several exotic mechanical,electrical,optical,and chemical properties that can be efficiently integrated into atomic-thin films.While previous reviews on 2D materials for biodevices primarily focus on conventional configurations and materials like graphene,the rapid development of new 2D materials with exotic properties has opened up novel applications,particularly in smart interaction and integrated functionalities.This review aims to consolidate recent progress,highlight the unique advantages of 2D materials,and guide future research by discussing existing challenges and opportunities in applying 2D materials for smart wearable biodevices.We begin with an in-depth analysis of the advantages,sensing mechanisms,and potential applications of 2D materials in wearable biodevice fabrication.Following this,we systematically discuss state-of-the-art biodevices based on 2D materials for monitoring various physiological signals within the human body.Special attention is given to showcasing the integration of multi-functionality in 2D smart devices,mainly including self-power supply,integrated diagnosis/treatment,and human–machine interaction.Finally,the review concludes with a concise summary of existing challenges and prospective solutions concerning the utilization of2D materials for advanced biodevices.
基金supported by the National Nat-ural Science Foundation of China(Nos.62174122,U2241244,and 52302046)Major Program(JD)of Hubei Province(No.2023BAA008)+2 种基金the Fundamental Research Funds for the Central Universities(Nos.2042023kf0116 and 2042023kf1041)the Guangdong Basic and Applied Basic Research Foundation(Nos.2024A1515011764 and 2024A1515010383)the Open Fund of Hubei Key Laboratory of Electronic Manufacturing and Packaging Integration(Wuhan University)(No.EMPI2023016).
文摘The surface transfer doping model has been extensively adopted as a mechanism to account for the generation of hole accumulation layers below hydrogen-terminated diamond(H-diamond)surfaces.To achieve effective surface transfer doping,surface electron acceptor materials with high electron affinity(EA)are required to produce a high density of two-dimensional hole gas(2DHG)on the H-diamond subsurface.We have established ingenious theoretical models to demonstrate that even if these solid materials do not have a high EA value,they remain capable of absorbing electrons from the H-diamond surface by forming a negatively charged interface to act as a surface electron acceptor in the surface transfer doping model.Our calculations,particularly for the local density of states,provide compelling evidence that the effect of an interface with negative charges induces an upward band bending on the H-diamond side.Furthermore,the valence band maximum of the diamond atoms at the interface crosses the Fermi level,giving rise to strong surface transfer p-type doping.These results give a strong theoretical interpretation of the origin of 2DHG on H-diamond surfaces.The proposed guidelines contribute to further improvements in the performance of 2DHG H-diamond field effect transistors.
基金supported by National Natural Science Foundation of China(Grant Nos.52305440,52204263)Natural Science Foundation of Changsha City(Grant Nos.kq2208272,kq2208274)+1 种基金Tribology Science Fund of the State Key Laboratory of Tribology in Advanced Equipment(Grant SKLTKF22B09)National Key Research and Development Program of China(2022YFB3706902).
文摘Laser-directed energy deposition(L-DED)is an advanced additive manufacturing technology primarily adopted in metal three-dimensional printing systems.The L-DED process is characterized by various defects,thus necessitating the extensive use of in-situ monitoring to enable real-time adjustments of process parameters by detecting molten-pool features.To address the challenge of accurately extracting the molten-pool morphology from an undetached spatter,an innovative monitoring method based on the U-Net(U-shaped network)is proposed herein.A lightweight architecture accelerates the processing speed,whereas an enhanced loss function incorporating weight maps augments the segmentation precision.The model performance is evaluated by comparing its segmentation accuracy and processing speed with those of the conventional U-Net,using the mean intersection over union(MIoU)as the segmentation metric.The improved model demonstrates superior segmentation accuracy at the interface between the molten pool and spatter,with a peak MIoU of 0.9798 achieved on the test set.Furthermore,this model processes each image in an extremely short time of 17.9 ms.Using this segmentation algorithm,the error in extracting the molten-pool width from single-track experiments is within 0.1 mm.The proposed method for monitoring the molten-pool morphology is suitable for deployment in online monitoring systems,thus providing a foundation for subsequent process-parameter regulation.
基金funded by the National Science Centre,Poland,on the basis of the decision number UMO-2020/37/B/ST8/02097supported by the program“Excellence Initiative-Research University”for the AGH University of Krakow(IDUB AGH,No.501.696.7996,Action 4,ID 9880).
文摘Multicomponent Gd_(1−x)Sm_(x)Ba_(0.5)Sr_(0.5)CoCuO_(5+δ)double perovskites are optimized for application in terms of chemical composi-tion and morphology for the use as oxygen electrodes in solid oxide cells.Structural studies of other physicochemical properties are con-ducted on a series of materials obtained by the sol-gel method with different ratios of Gd and Sm cations.It is documented that changing the x value,and the resulting adjustment of the average ionic radius,have a significant impact on the crystal structure,stability,as well as on the total conductivity and thermomechanical properties of the materials,with the best results obtained for the Gd_(0.75)Sm_(0.2)5Ba_(0.5)Sr_(0.5)CoCuO_(5+δ)composition.Oxygen electrodes are prepared using the selected compound,allowing to obtain low polarization resistance values,such as 0.086Ω·cm^(2)at 800℃.Systematic studies of electrocatalytic activity are conducted using La_(0.8)Sr_(0.2)Ga_(0.8)Mg_(_(0.2))O_(3−δ)as the electrolyte for all electrodes,and Ce_(0.8)Gd_(0.2)O_(2−δ)electrolyte for the best performing Gd_(0.75)Sm_(0.2)5Ba_(0.5)Sr_(0.5)CoCuO_(5+δ)electrodes.The electrochemical data are analyzed using the distribution of relaxation times method.Also,the influence of the preparation method of the electrode material is in-ve`stigated using the electrospinning technique.Finally,the performance of the Gd_(0.75)Sm_(0.2)5Ba_(0.5)Sr_(0.5)CoCuO_(5+δ)electrodes is tested in a Ni-YSZ(yttria-stabilized zirconia)anode-supported cell with a Ce_(0.8)Gd_(0.2)O_(2−δ)buffer layer,in the fuel cell and electrolyzer operating modes.With the electrospun electrode,a power density of 462 mW·cm^(−2)is obtained at 700℃,with a current density of ca.0.2 A·cm^(−2)at 1.3 V for the electrolysis at the same temperature,indicating better performance compared to the sol-gel-based electrode.
基金funded by the National Natural Science F oundation of China(No.52172205)。
文摘Zinc oxide(ZnO)serves as a crucial functional semiconductor with a wide direct bandgap of approximately 3.37 eV.Solvothermal reaction is commonly used in the synthesis of ZnO micro/nanostructures,given its low cost,simplicity,and easy implementation.Moreover,ZnO morphology engineering has become desirable through the alteration of minor conditions in the reaction process,particularly at room temperature.In this work,ZnO micro/nanostructures were synthesized in a solution by varying the amounts of the ammonia added at low temperatures(including room temperature).The formation of Zn^(2+)complexes by ammonia in the precursor regulated the reaction rate of the morphology engineering of ZnO,which resulted in various structures,such as nanoparticles,nanosheets,microflowers,and single crystals.Finally,the obtained ZnO was used in the optoelectronic application of ultraviolet detectors.
基金National Natural Science Foundation of China,No.41906148,No.42271086Rejuvenating Yunnan Talents Support Plan Young Talent Program,No.XDYC-QNRC-2023-0322。
文摘A macro-tidal tropical estuary with high fluvial discharge is characterized by both fragility and remarkable dynamism.This study utilizes the Salween River Delta(SRD)as a case example to examine the interplay between morphology and vegetation under similar tidal conditions.Our analysis of correlations and inferences revealed several significant trends in the SRD:(1)an overall expansion of land area and intertidal vegetation,with the most pronounced changes occurring in the eastern sector;(2)the predominance of river discharge influencing the southwestern and northern sectors,contrasted with the primary impact of storm surges in the eastern sector;and(3)three distinct causal relationships among estuarine morphology,vegetation,storm surges,and river discharge:a direct model where river discharge shapes estuarine morphology,a progressive model in which river discharge affects vegetation distribution,subsequently influencing estuarine morphology,and a hybrid model where storm surges directly impact vegetation and indirectly modify its distribution through changes in estuarine morphology.The stability of sediment supply and the role of intertidal vegetation are crucial for the continuous seaward advance,providing a vital foundation for the protection and development of estuarine deltas.
基金financially supported by the Natural Science Foundation of Guangdong Province(No.2024A1515010639)PolyU Postdoc Matching Fund Scheme(No.1-W327),PolyU Grant(No.1-CE0H)+3 种基金Shenzhen Science and Technology Program(No.ZDSYS20220606100406016)Shenzhen Key Laboratory of Photonics and Biophotonics(No.ZDSYS20210623092006020)National Key Laboratory of Green and Long-Life Road Engineering in Extreme Environment(Shenzhen)(No.868-000003010103)National Natural Science Foundation of China(No.52208272)。
文摘Fueled by the increasing imperative for sustainable energy solutions and the burgeoning emphasis on health awareness,self-powered techniques have undergone notable strides in advancement.Triboelectric nanogenerators(TENGs)stand out as a prominent device capitalizing on the principles of triboelectrification and electrostatic induction to generate electricity or electrical signals.In efforts to augment the electrical output performance of TENGs and broaden their range of applications,researchers have endeavored to refine materials,surface morphology,and structural design.Among them,physical morphological modifications play a pivotal role in enhancing the electrical properties of TENGs by increasing the contact surface area,which can be achieved by building micro-/nano-structures on the surface or inside the friction material.In this review,we summarize the common morphologies of TENGs,categorize the morphologies into surface and internal structures,and elucidate their roles in enhancing the electric output performance of devices.Moreover,we systematically classify the methodologies employed for morphological preparation into physical and chemical approaches,thereby furnishing a comprehensive survey of the diverse techniques.Subsequently,typical applications of TENGs with special morphology divided by energy harvesting and self-powered sensors are presented.Finally,an overview of the challenges and future trajectories pertinent to TENGs is conducted.Through this endeavor,the aim of this article is to catalyze the evolution of further strategies for enhancing performance of TENGs.
基金supported by the National Key Research and Development Program of China,No.2021ZD0202503(to AHT)the National Natural Science Foundation of China,Nos.31872759(to AHT)and 32070707(to CF)+1 种基金Shenzhen Science and Technology Program,No.RCJC20210609104333007(to ZW)Shenzhen-Hong Kong Institute of Brain Science,Shenzhen Fundamental Research Institutions,No.2021SHIBS0002(to ZW).
文摘Morphological alterations in dendritic spines have been linked to changes in functional communication between neurons that affect learning and memory.Kinesin-4 KIF21A helps organize the microtubule-actin network at the cell cortex by interacting with KANK1;however,whether KIF21A modulates dendritic structure and function in neurons remains unknown.In this study,we found that KIF21A was distributed in a subset of dendritic spines,and that these KIF21A-positive spines were larger and more structurally plastic than KIF21A-negative spines.Furthermore,the interaction between KIF21A and KANK1 was found to be critical for dendritic spine morphogenesis and synaptic plasticity.Knockdown of either KIF21A or KANK1 inhibited dendritic spine morphogenesis and dendritic branching,and these deficits were fully rescued by coexpressing full-length KIF21A or KANK1,but not by proteins with mutations disrupting direct binding between KIF21A and KANK1 or binding between KANK1 and talin1.Knocking down KIF21A in the hippocampus of rats inhibited the amplitudes of long-term potentiation induced by high-frequency stimulation and negatively impacted the animals’cognitive abilities.Taken together,our findings demonstrate the function of KIF21A in modulating spine morphology and provide insight into its role in synaptic function.
文摘A functional interlayer based on two-dimensional(2D)porous modified vermiculite nanosheets(PVS)was obtained by acid-etching vermiculite nanosheets.The as-obtained 2D porous nanosheets exhibited a high specific surface area of 427 m^(2)·g^(-1)and rich surface active sites,which help restrain polysulfides(LiPSs)through good physi-cal and chemical adsorption,while simultaneously accelerating the nucleation and dissolution kinetics of Li_(2)S,effec-tively suppressing the shuttle effect.The assembled lithium-sulfur batteries(LSBs)employing the PVS-based inter-layer delivered a high initial discharge capacity of 1386 mAh·g^(-1)at 0.1C(167.5 mAh·g^(-1)),long-term cycling stabil-ity,and good rate property.
基金supported by the Shihezi University High-Level Talents Research Startup Project(Project No.RCZK202521)the National Natural Science Foundation of China(Grant Nos.12271066,11871121,12171405)+1 种基金the Chongqing Natural Science Foundation Joint Fund for Innovation and Development Project(Project No.CSTB2024NSCQLZX0085)the Chongqing Normal University Foundation(Grant No.23XLB018).
文摘This paper investigates ruin,capital injection,and dividends for a two-dimensional risk model.The model posits that surplus levels of insurance companies are governed by a perturbed composite Poisson risk model.This model introduces a dependence between the two surplus levels,present in both the associated perturbations and the claims resulting from common shocks.Critical levels of capital injection and dividends are established for each of the two risks.The surplus levels are observed discretely at fixed intervals,guiding decisions on capital injection,dividends,and ruin at these junctures.This study employs a two-dimensional Fourier cosine series expansion method to approximate the finite time expected discounted operating cost until ruin.The ensuing approximation error is also quantified.The validity and accuracy of the method are corroborated through numerical examples.Furthermore,the research delves into the optimal capital allocation problem.
文摘Introduction: the left atrial appendage, a dormant embryonic vestige, would play a major role in cardiac hemodynamic changes, volume homeostasis and thrombi formation. It, therefore constitutes a therapeutic target. Its morphology is extremely variable. Objective: it consisted on determining the morphological variations of the left auricle as well as their interest in the prevention of thrombi in the Senegalese. Material and Method: This study was conducted by dissecting 36 fresh hearts from Senegalese anatomical subjects with a sampling of the left atrial appendage, including specimens with normal morphological appearance. Their morphology was studied using the fresh and frozen plaster molding method. The data obtained were analyzed statistically. Results: the average age of the subjects was 33 years, with a sex ratio of 1.06, the cauliflower shape was dominant with 57% of cases and the cactus shape (4%) was less frequent. The cauliflower shape presented a clear angulation compared to the others without statistically significant differences according to age. Conclusion: This work showed a great morphological variability of the left atrial appendage. It can provide an update on the specificity of Senegalese. Taking these variations into account is important in the safe management of hemodynamic conditions and the improvement of the management of recurrent strokes.
基金supported by Beijing Natural Science Foundation(Nos.2232037 and 2242035)the National Natural Science Foundation of China(Nos.22005012,22105012 and 51803183)+1 种基金Chunhui Plan Cooperative Project of Ministry of Education(No.202201298)the China Postdoctoral Science Foundation Funded Project(No.2023M733520).
文摘Lithium-sulfur(Li-S)batteries with high energy density and capacity have garnered significant research attention among various energy storage devices.However,the shuttle effect of polysulfides(LiPSs)remains a major challenge for their practical application.The design of battery separators has become a key aspect in addressing the challenge.MXenes,a promising two-dimensional(2D)material,offer exceptional conductivity,large surface area,high mechanical strength,and active sites for surface reactions.When assembled into layered films,MXenes form highly tunable two-dimensional channels ranging from a few angstroms to over 1 nm.These nanoconfined channels are instrumental in facilitating lithium-ion transport while effectively impeding the shuttle effect of LiPSs,which are essential for improving the specific capacity and cyclic stability of Li-S batteries.Substantial progress has been made in developing MXenes-based separators for Li-S batteries,yet there remains a research gap in summarizing advancements from the perspective of interlayer engineering.This entails maintaining the 2D nanochannels of layered MXenes-based separators while modulating the physicochemical environment within the MXenes interlayers through targeted modifications.This review highlights advancements in in situ modification of MXenes and their integration with 0D,1D,and 2D materials to construct laminated nanocomposite separators for Li-S batteries.The future development directions of MXenes-based materials in Li-S energy storage devices are also outlined,to drive further advancements in MXenes for Li-S battery separators.
基金supported by the National Natural Science Foundation of China(22376063,21976057)the Fund of the National Engineering Laboratory for Mobile Source Emission Control Technology(NELMS2020A05)Fundamental Research Funds for the Central Universities.
文摘The preferential oxidation of CO(CO-PROX)reaction is a cost-effective method for eliminating trace amounts of CO from the fuel H2.Pt-based catalysts have been extensively studied for COPROX,with their activity influenced by the morphology of the support.Hydrothermal synthesis was employed to produce different morphologies ofγ-Al_(2)O_(3):flower-likeγ-Al_(2)O_(3)(f)exposing(110)crystal faces,sheet-likeγ-Al_(2)O_(3)(s)revealing(100)crystal faces,and rod-likeγ-Al_(2)O_(3)(r)displaying(111)crystal faces,followed by loading PtCo nanoparticles.The exposed crystal faces of the support impact the alloying degree of the PtCo nanoparticles,and an increase in the alloying degree correlates with enhanced catalyst reactivity.Pt_(3)Co intermetallic compounds were identified onγ-Al_(2)O_(3)(f)exposing(110)crystal faces,and PtCo/γ-Al_(2)O_(3)(f)showed high catalytic activity in the CO-PROX reaction,achieving 100%CO conversion across a broad temperature range of 50−225°C.In contrast,only partial alloying of PtCo was observed onγ-Al_(2)O_(3)(s).Furthermore,no alloying between Pt and Co occurred in PtCo/γ-Al_(2)O_(3)(r),resulting in a reaction rate at 50°C that was merely 11%of that of PtCo/γ-Al_(2)O_(3)(f).The formation of Pt3Co intermetallic compounds led to a more oxidized state of Pt,which significantly diminished the adsorption of CO on Pt and augmented the active oxygen species,thereby facilitating the selective oxidation of CO.
基金supported by the National Key Research and Development Project(No.2019YFA0705403)the National Natural Science Foundation of China(No.T2293693,52273311)+2 种基金the Guangdong Basic and Applied Basic Research Foundation(No.2020B0301030002)and the Shenzhen Basic Research Project(Nos.WDZC20200824091903001,JSGG20220831105402004,JCYJ20220818100806014)Shenzhen Major Science and Technology Projects(Nos.KCXFZ20240903094013018,KCXFZ20240903094203005)。
文摘Titanium dioxide(TiO_(2))has been an important protective ingredient in mineral-based sunscreens since the 1990s.However,traditional TiO_(2)nanoparticle formulations have seen little improvement over the past decades and continue to face persistent challenges related to light transmission,biosafety,and visual appearance.Here,we report the discovery of two-dimensional(2D)TiO_(2),characterized by a micro-sized lateral dimension(~1.6μm)and atomic-scale thickness,which fundamentally resolves these long-standing issues.The 2D structure enables exceptional light management,achieving 80%visible light transparency—rendering it nearly invisible on the skin—while maintaining UV-blocking performance comparable to unmodified rutile TiO_(2)nanoparticles.Its larger lateral size results in a two-orders-of-magnitude reduction in skin penetration(0.96 w/w%),significantly enhancing biosafety.Moreover,the unique layered architecture inherently suppresses the generation of reactive oxygen species(ROS)under sunlight exposure,reducing the ROS generation rate by 50-fold compared to traditional TiO_(2)nanoparticles.Through precise metal element modulation,we further developed the first customizable sunscreen material capable of tuning UV protection ranges and automatically matching diverse skin tones.The 2D TiO_(2)offers a potentially transformative approach to modern sunscreen formulation,combining superior UV protection,enhanced safety and a natural appearance.
