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Sn-fused perylene diimides: Synthesis, mechanism, and properties

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Chinese Chemical letters 2024年第10期35卷 244-248页

作者： Wenzhong Zhang Zirui Yan Lingcheng chen yi Xiao State Key Laboratory of Fine Chemicals Dalian University of TechnologyDalian 116024China

The first example of metal Sn-fused perylene diimides(PDI)derivative(Sn-PDI)was designed,synthesized,and *** obtain this type compound,a simple one-pot synthesis,named stannylative cycloaddition reaction,has been successfully developed via a palladium-based catalyst *** novel mechanism exhibits that the reaction experiences oxidative addition,Pd-cyclization,stannylation,Pd-Sn-cyclization,and reductive elimination processes *** stannylative cycloaddition does realize uniqueσ-πhyperconjugation effect and therefore significantly influencing on the photophysical,electrochemical and excited state *** with those of PDI,both of the absorption and fluorescence spectra of Sn-PDI display large red-shifts over 20 *** electron energy levels of Sn-PDI have changed with an uncommon *** Sn-PDI gives a considerably raised highest occupied molecular orbital(HOMO)level of-6.00 eV More importantly,the singlet excitons of Sn-PDI could efficiently intersystem cross(ISC)into triplet state with a long lifetime of 17.8μs,which is far longer than that(4.4 ns)of PDI.

关键词： Functional dyes Perylene diimides Organometallic heterocyclics Hyperconjugation Triplet state

Sodium intake:a double-edged sword wielded by the brain

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Science China(Life Sciences) 2024年第7期67卷 1545-1547页

作者： Lingyu Xu Xiaolong Ma yi Wang Zhong chen Key Laboratory of Neuropharmacology and Pharmaceutical Sciences Zheiiang Chinese Medical UniversityHangzhou 310053China Institute of Pharmacology&Toxicology College of Pharmaceutical SciencesZhejiang UniversityHangzhou 310058China

Taste receptors on the tongue discriminate between five fundamental tastes:sour,sweet,bitter,salty,and umami(Chandrashekar et al.,2006).Typically,stimuli that evoke bitterness and acidity prompt aversive responses by animals,whereas sweet and umami flavors are appetitive and *** is unique in that it transitions from an appetitive to an aversive stimulus with increasing concentrations.

关键词： prompt sweet sword

Evaluation on cutting performance of novel PDC cutter for pipe jacking machine

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Underground Space 2024年第1期14卷 34-52页

作者： Long-Chuan Deng yi-Xiang Yuan Xiao-Zhao Li Qian-Wei Zhuang Chi Zhang yi-Wei chen School of Earth Sciences and Engineering Nanjing UniversityNanjingJiangsu 210023China Shanghai Tunnel Engineering Co.Ltd. Shanghai 200232China State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhouJiangsu 221116China School of Mechanics and Engineering Science Shanghai UniversityShanghai 200444China

It is inevitable to cut reinforced concrete(RC)appeared in cross passage of city metro by cutting tools when constructing in densely populated *** previous cutters employed to cut RC are insufficient and easily damaged,so a new polycrystalline diamond compact(PDC)cutter is used to solve this *** on the theoretical analysis of cutting mechanism,both circular and tapered PDC cutters with cutting edge angle of 90and negative front rack angle of 10are used to cut *** peeling and breaking patterns of cutting concrete are proposed,the nodular and grainy chips are the preferred modes in cutting steel *** LS-DYNA is employed to investigate the cutting performance in *** simulation results show that the average and peak cutting forces increase with the growth of penetration depth,cutting speed,and roundness,and subsequently the recommended penetration depth less than 1.2 mm is obtained to cut RC due to the existence of steel ***,the linear cutting platform is adopted to investigate the force ability and damage state of PDC *** is concluded that the cutting force increases abruptly and fluctuates heavily when cutting the coarse *** patterns occurred in both numerical and experimental results are generally ***,the steel bar is pulled out and the PDC cutter is damaged at the penetration depth of 0.8 mm,while a good cut occurs at the penetration depth of 0.3 *** tapered PDC cutter with a relatively low cutting force is prone to be broken compared with circular PDC *** is suggested that the circular PDC cutter at the penetration depth of 0.3 mm should be used to cut RC in practical engineering.

关键词： PDC cutter RC Pipe jacking machine Linear cutting tests Damage and wear LS-DYNA

Exercise-induced adaptation of neurons in the vertebrate locomotor system

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Journal of Sport and Health Science 2024年第2期13卷 160-171页

作者： Yue Dai yi cheng Renkai Ge Ke chen Liming Yang Key Lab of Adolescent Health Assessment and Exercise Intervention of Ministry of Education College of Physical Education and Health CareEast China Normal UniversityShanghai 200241China Shanghai Key Laboratory of Multidimensional Information Processing School of Communication and Electronic EngineeringEast China Normal UniversityShanghai 200241China School of Physical Education and Health Care East China Jiaotong UniversityNanchang 330013China Key Laboratory of High Confidence Software Technologies of Ministry of Education School of Computer SciencePeking UniversityBeijing 100871China

Vertebrate neurons are highly dynamic cells that undergo several alterations in their functioning and physiologies in adaptation to various external *** particular,how these neurons respond to physical exercise has long been an area of active *** of the vertebrate locomotor system’s adaptability suggest multiple mechanisms are involved in the regulation of neuronal activity and properties during *** this brief review,we highlight recent results and insights from the field with a focus on the following mechanisms:(a)alterations in neuronal excitability during acute exercise;(b)alterations in neuronal excitability after chronic exercise;(c)exercise-induced changes in neuronal membrane properties via modulation of ion channel activity;(d)exercise-enhanced dendritic plasticity;and(e)exercise-induced alterations in neuronal gene expression and protein *** hope is to update the community with a cellular and molecular understanding of the recent mechanisms underlying the adaptability of the vertebrate locomotor system in response to both acute and chronic physical exercise.

关键词： Dendritic plasticity Excitability Exercise Ion channel modulation Neuron adaptation

Equilibrium Reinsurance Strategy and Mean Residual Life Function

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 758-777页

作者： Dan-ping LI Lv chen Lin-yi QIAN Wei WANG School of Statistics Key Laboratory of Advanced Theory and Application in Statistics and Data Science-MOEEast China Normal UniversityShanghai 200062China Academy of Statistics and Interdisciplinary Sciences Key Laboratory of Advanced Theory and Application in Statistics and Data Science-MOEEast China Normal UniversityShanghai 200062China School of Mathematics and Statistics Ningbo UniversityNingbo 315211China

In this paper,we analyze the relationship between the equilibrium reinsurance strategy and the tail of the distribution of the *** Mean Residual Life(MRL)has a close relationship with the tail of the distribution,we consider two classes of risk distributions,Decreasing Mean Residual Life(DMRL)and Increasing Mean Residual Life(IMRL)distributions,which can be used to classify light-tailed and heavy-tailed distributions,*** assume that the underlying risk process is modelled by the classical CramérLundberg model *** the mean-variance criterion,by solving the extended Hamilton-Jacobi-Bellman equation,we derive the equilibrium reinsurance strategy for the insurer and the reinsurer under DMRL and IMRL,***,we analyze how to choose the reinsurance premium to make the insurer and the reinsurer agree with the same reinsurance *** find that under the case of DMRL,if the distribution and the risk aversions satisfy certain conditions,the insurer and the reinsurer can adopt a reinsurance premium to agree on a reinsurance strategy,and under the case of IMRL,the insurer and the reinsurer can only agree with each other that the insurer do not purchase the reinsurance.

关键词： mean residual life excess-of-loss reinsurance insurer reinsurer stochastic control

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lean methane combustion over zeolite-supported Pd catalysts:Structure-performance relationship and deactivation mechanism

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Journal of Environmental Sciences 2024年第11期145卷 128-138页

作者： Xingyu Liu Jingkun chen Bowen Han Renna Li le Shi Zhongbiao Wu Xiaole Weng Key Laboratory of Environment Remediation and Ecological Health Ministry of EducationCollege of Environmental and Resource SciencesZhejiang UniversityHangzhou 310058China ZJU-Hangzhou Global Scientific and Technological Innovation Center Zhejiang UniversityHangzhou 311200China Zhejiang Provincial Engineering Research Centre of Industrial Boiler&Furnace Flue Gas Pollution Control Hangzhou 310058China

Zeolites are a promising support for Pd catalysts in leanmethane(CH_(4))***,three types of zeolites(H-MOR,H-ZSM-5 and H-Y)were selected to estimate their structural effects and deactivation mechanisms in CH_(4)*** show that variations in zeolite structure and surface acidity led to distinct changes in Pd ***/H-MOR with external high-dispersing Pd nanoparticles exhibited the best apparent activity,with activation energy(Ea)at 73 kJ/mol,while Pd/H-ZSM-5 displayed the highest turnover frequency(TOF)at 19.6×10^(−3)sec^(−1),presumably owing to its large particles with more step sites providing active sites in one particle for CH_(4)***/H-Y with dispersed PdO within pore channels and/or Pd2+ions on ion-exchange sites yielded the lowest apparent activity and ***,Pd/H-MOR and Pd/H-ZSM-5 were both stable under a dry condition,but introducing 3 vol.%H_(2)O caused the CH_(4)conversion rate on Pd/H-MOR drop from 100%to 63%and that on Pd/H-ZSM-5 decreased remarkably from 82%to 36%.The former was shown to originate fromzeolite structural dealumination,and the latter principally owed to Pd aggregation and the loss of active PdO.

关键词： Methane combustion Pd catalysts Zeolite Structure-performance relationship Deactivation mechanism

Spherical Bi_(2)O_(3)/ATO catalyst with N_(2)pre-reduction electrocatalytic reduction of CO_(2)to formic acid

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Journal of Environmental Sciences 2024年第6期140卷 331-340页

作者： Junying yi Yuli chen Dongze Lai Bihong Lv Xiaomin Wu Guohua Jing Department of Environmental Science&Engineering College of Chemical EngineeringHuaqiao UniversityXiamenFujian 361021China

To achieve carbon neutrality,the Chinese government needs to gain a comprehensive understanding of the sources and drivers of greenhouse gas(GHG)emissions,particularly at the county *** County in eastern China is a typical example of an industrial transformation from quarrying to a low-carbon *** study analyzed the decoupling types and structural characteristics of GHG emissions and the driving factors of carbon dioxide(CO_(2))emissions in the Anji from 2006 to 2019,and explored the differences between countylevel and provincial-level or city-level *** was observed that energy-related activities are the main source of GHG emissions in Anji and that economic development is the driving factor behind the increasing CO_(2)***,industrial transformation and upgradation coupled with the alternative use of clean energy limit the growth of GHG *** study details the GHG emissions of county during the industrial transformation stage and provides corresponding policy recommendations for county governments.

关键词： N_(2)prereduction CO_(2)electroreduction Bi_(2)O_(3)/ATO catalyst Formate

Genomic divergence and mutation load in the Begonia masoniana complex from limestone karsts

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Plant Diversity 2024年第5期46卷 575-584页

作者： yiqing chen Lina Dong Huiqin yi Catherine Kidner Ming Kang Key Laboratory of National Forestry and Grassland Administration on Plant Conservation and Utilization in Southern China Guangzhou 510650China University of Chinese Academy of Sciences Beijing 100049China Guangxi Key Laboratory of Conservation and Restoration Ecology in Karst Terrain Guangxi Institute of BotanyGuangxi Zhang Autonomous Region and the Chinese Academy of SciencesGuilin 541006China Institute of Molecular Plant Sciences University of EdinburghDaniel Rutherford Building Max Born CrescentThe King's BuildingsEdinburgh EH93BFUK Royal Botanic Garden Edinburgh 20a Inverleith RowEdinburgh EH35LRUK State Key Laboratory of Plant Diversity and Specialty Crops South China Botanical GardenChinese Academy of SciencesGuangzhou 510650China

Understanding genome-wide diversity,inbreeding,and the burden of accumulated deleterious mutations in small and isolated populations is essential for predicting and enhancing population persistence and ***,these effects are rarely studied in limestone karst ***,we re-sequenced the nuclear genomes of 62 individuals of the Begonia masoniana complex(***,***,*** and ***)and investigated genomic divergence and genetic load for these four *** analyses revealed four distinct clusters corresponding to each species within the ***,there was only limited admixture between *** and *** occurring in overlapping geographic *** species experienced historical bottlenecks during the Pleistocene,which were likely caused by glacial climate *** detected an asymmetric historical gene flow between group pairs within this timeframe,highlighting a distinctive pattern of interspecific divergence attributable to karst geographic *** found that isolated populations of *** have limited gene flow,the smallest recent population size,the highest inbreeding coefficients,and the greatest accumulation of recessive deleterious *** findings underscore the urgency to prioritize conservation efforts for these isolated *** study is among the first to disentangle the genetic differentiation and specific demographic history of karst Begonia plants at the whole-genome level,shedding light on the potential risks associated with the accumulation of deleterious mutations over generations of ***,our findings may facilitate conservation planning by providing critical baseline genetic data and a better understanding of the historical events that have shaped current population structure of rare and endangered karst plants.

关键词： Conservation genomics Karst landscape Demographic history Inbreeding Isolated populations Mutation load

An anti-icing scaling method for wind tunnel tests of aircraft thermal ice protection system

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Chinese Journal of Aeronautics 2024年第6期37卷 1-6页

作者： Yu LIU Qiang WANG Xian yi Ningli chen Jinghao REN Weihao LI Key Laboratory of Icing and Anti/de-icing China Aerodynamics Research and Development CenterMianyang 621000China State Key Laboratory of Aerodynamics Mianyang 621000China

The efficiency of the aircraft Ice Protection Systems(IPSs)needs to be verified through icing wind tunnel ***,the scaling method for testing the IPSs has not been systematically established yet,and further research is *** the present study,a scaling method specifically designed for thermal IPSs was derived from the governing equation of thin water *** scaling parameters were adopted to address the heat and mass transfer involved in the thermal anti-icing *** method validation,icing wind tunnel tests were conducted using a jet engine nacelle model equipped with a bleed air *** non-dimensional surface temperature and runback ice closely matched for both the reference and scaled *** validation confirms that the scaling method is capable of achieving the similarity of surface temperature and the runback ice *** anti-icing scaling method can serve as an important supplement to the existing icing similarity theory.

关键词： Scaling method Ice protection system Water film Anti-icing test Icing wind tunnel