Optimizing electronic structure through point defect engineering for enhanced electrocatalytic energy conversion

Point defect engineering endows catalysts with novel physical and chemical properties,elevating their electrocatalytic efficiency.The introduction of defects emerges as a promising strategy,effectively modifying the electronic structure of active sites.This optimization influences the adsorption energy of intermediates,thereby mitigating reaction energy barriers,altering paths,enhancing selectivity,and ultimately improving the catalytic efficiency of electrocatalysts.To elucidate the impact of defects on the electrocatalytic process,we comprehensively outline the roles of various point defects,their synthetic methodologies,and characterization techniques.Importantly,we consolidate insights into the relationship between point defects and catalytic activity for hydrogen/oxygen evolution and CO_(2)/O_(2)/N_(2) reduction reactions by integrating mechanisms from diverse reactions.This underscores the pivotal role of point defects in enhancing catalytic performance.At last,the principal challenges and prospects associated with point defects in current electrocatalysts are proposed,emphasizing their role in advancing the efficiency of electrochemical energy storage and conversion materials.

Parameters Optimization and Performance Evaluation of the Tuned Inerter Damper for the Seismic Protection of Adjacent Building Structures

In order to improve the seismic performance of adjacent buildings,two types of tuned inerter damper(TID)damping systems for adjacent buildings are proposed,which are composed of springs,inerter devices and dampers in serial or in parallel.The dynamic equations of TID adjacent building damping systems were derived,and the H2 norm criterion was used to optimize and adjust them,so that the system had the optimum damping performance under white noise random excitation.Taking TID frequency ratio and damping ratio as optimization parameters,the optimum analytical solutions of the displacement frequency response of the undamped structure under white noise excitation were obtained.The results showed that compared with the classic TMD,TID could obtain a better damping effect in the adjacent buildings.Comparing the TIDs composed of serial or parallel,it was found that the parallel TIDs had more significant advantages in controlling the peak displacement frequency response,while the H2 norm of the displacement frequency response of the damping system under the coupling of serial TID was smaller.Taking the adjacent building composed of two ten-story frame structures as an example,the displacement and energy collection time history analysis of the adjacent building coupled with the optimum design parameter TIDs were carried out.It was found that TID had a better damping effect in the full-time range compared with the classic TMD.This paper also studied the potential power of TID in adjacent buildings,which can be converted into available power resources during earthquakes.

Two-Dimensional Metallophthalocyanine Nanomaterials for Electrocatalytic Energy Conversion

Growing energy demand drives the rapid development of clean and reliable energy sources.In the past years,the exploration of novel materials with considerable efficiency and durability has drawn attention in the area of electrochemical energy conversion.Transition metal macrocyclic metallophthalocyanines(MPcs)-based catalysts with a peculiar 2D constitution have emerged with a promising future account of their highly structural tailorability and molecular functionality which greatly extend their functionalities as electrocatalytic materials for energy conversion.This review summarizes the systematic engineering of synthesis of MPcs and their analogs in detail,and mostly pays attention to the frontier research of MPc-based high-performance catalysts toward different electrocatalytic processes concerning hydrogen,oxygen,water,carbon dioxide,and nitrogen,with a particular focus on discussing the interrelationship between the electrocatalytic activity and component/structure,as well as functional applications of MPcs.Finally,we give the gaps that need to be addressed after much thought.

VqMAPK3/VqMAPK6, VqWRKY33, and VqNSTS3 constitute a regulatory node in enhancing resistance to powdery mildew in grapevine

Grapevine powdery mildew is caused by Erysiphe necator,which seriously harms grape production in the world.Stilbene synthase makes phytoalexins that contribute to the resistance of grapevine against powdery mildew.A novel VqNSTS3 was identified and cloned from Chinese wild Vitis quinquangularis accession Danfeng-2.The novel VqNSTS3 was transferred into susceptible‘Thompson Seedless’by Agrobacterium-mediated transformation.The transgenic plants showed resistance to the disease and activated other resistance-related genes.VqNSTS3 expression in grapevine is regulated by VqWRKY33,and which binds to TTGACC in the VqNSTS3 promoter.Furthermore,VqWRKY33 was phosphorylated by VqMAPK3/VqMAPK6 and thus led to enhanced signal transduction and increased VqNSTS3 expression.ProVqNSTS3::VqNSTS3-GFP of transgenic VqNSTS3 in Arabidopsis thaliana was observed to move to and wrap the pathogen’s haustoria and block invasion by Golovinomyces cichoracearum.These results demonstrate that stilbene accumulation of novel VqNSTS3 of the Chinese wild Vitis quinquangularis accession Danfeng-2 prevented pathogen invasion and enhanced resistance to powdery mildew.Therefore,VqNSTS3 can be used in generating powdery mildew-resistant grapevines.

碱性介质中Ni-Fe层状双氢氧化物析氧催化剂的研究进展

电催化水裂解被广泛认为是一种非常有前景的制氢路线之一,这一反应过程包括析氢反应和析氧反应.与析氢反应相比,析氧反应涉及多步质子耦合-电子转移过程,需要较大的活化能垒和过电势,因此是水裂解反应的瓶颈.Ni-Fe层状双氢氧化物因其独特的层状结构和优异的析氧反应性能而备受关注.本文首先介绍了电催化析氧反应的机理以及评价电催化剂性能的关键参数和标准,讨论了Ni-Fe层状双氢氧化物催化剂的制备方法,随后重点综述了析氧反应性能优化策略,如构筑纳米结构、掺杂异原子、构建异质结构、负载单原子、调控缺陷位、扩大层间距等方法.最后,对Ni-Fe LDH催化剂未来发展提出了展望和挑战.

A Tuberculosis Outbreak at a School-Xinjiang Uygur Autonomous Region, China, 2019

Summary What is already known about this topic?Worldwide,tuberculosis(TB)continues to be the most important cause of death from a single infectious agent,and China has a high TB burden.Although the reported incidence of TB in students is lower than that in general population,TB outbreaks in schools have continuously been reported in the past years,suggesting that schools are a high-risk setting for TB transmission.

A Miniature Video Stabilization System for Flapping-Wing Aerial Vehicles

In this paper,a miniature video stabilization system is designed to deal with the image jitter and motion blur problem for°apping-wing aerial vehicles(FWAVs).First,a light and two-axis pan–tilt(about 13 g)is built for the FWAV to counteract most of the jitter e®ect.Then,an electronic image stabilization method combined with a Micro-Electro Mechanical Systems(MEMSs)gyroscope is proposed to further stabilize the images.Finally,°ight experiment results show that the designed video stabilization system e®ectively improves the quality of aerial videos.

Exploring the impact of new particle formation events on PM_(2.5) pollution during winter in the Yangtze River Delta,China

New particle formation(NPF)events are an increasingly interesting topic in air quality and climate science.In this study,the particle number size distributions,and the frequency of NPF events over Hefei were investigated from November 2018 to February 2019.The proportions of the nucleation mode,Aitken mode,and accumulation mode were 24.59%,53.10%,and 22.30%,respectively,which indicates the presence of abundant ultrafine particles in Hefei.Forty-six NPF events occurred during the observation days,accounting for 41.82%of the entire observation period.Moreover,the favorable meteorological conditions,potential precursor gases,and PM_(2.5)range of the NPF events were analyzed.Compared to non-NPF days,the NPF events preferentially occurred on days with lower relative humidity,higher wind speeds,and higher temperatures.When the PM_(2.5) was 15–20,70–80,and105–115μg/m^(3),the frequency of the NPF events was higher.Nucleation mode particles were positively related to atmospheric oxidation indicated by ozone when PM_(2.5) ranged from 15 to 20μg/m^(3),and related to gaseous precursors like SO_(2) and NO_(2) when PM_(2.5)was located at 70-80 and 105–115μg/m^(3).On pollution days,NPF events did not directly contribute to the increase in the PM_(2.5) in the daytime,however,NPF events would occur during the night and the growth of particulate matter contributes to the nighttime PM_(2.5) contents.This could lead to pollution that lasted into the next day.These findings are significant to the improvement of our understanding of the effects of aerosols on air quality.