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Journal of Energy Chemistry 2024年第10期97卷 470-477,I0010页

作者： Xiaoman Ye xuemei Xiao Zhijing Wu Xin Wu Lin Gu Sheng Liu School of Chemical Engineering and Technology Sun Yat-sen UniversityZhuhai 519082GuangdongChina The Key Lab of Low-Carbon Chemistry&Energy Conservation of Guangdong Province Sun Yat-sen UniversityGuangzhou 510275GuangdongChina

The notorious growth of zinc dendrite and the water-induced corrosion of zinc metal anodes(ZMAs)restrict the practical development of aqueous zinc ion batteries(AZIBs).In this work,a zinc metallized,imide-pillared covalent organic framework(ZPC)protective film has been engineered as a stable Zn^(2+)ion-conducting interphase to modulate interfacial kinetics and suppress side reactions for *** to bare Zn,ZPC@Zn exhibits a higher Zn^(2+)ionic conductivity,a larger Zn^(2+)transference number,a lower electronic conductivity,a smaller desolvation activation energy and correspondingly a significant suppression of corrosion,hydrogen evolution and Zn ***,the ZPC@Zn||ZPC@Zn symmetric cell obtains a cycling lifespan over 3000 h under 5 mA cm^(-2)for 1 mA h cm^(-2).The ZPC@Zn||NH_(4)V_(4)O_(10)coin-type full battery delivers a specific capacity of 195.8 mA h g^(-1)with a retention rate of78.5%at 2 A g^(-1)after 1100 cycles,and the ZPC@Zn||NH_(4)V_(4)O_(10) pouch full cell shows a retention of70.1%in reversible capacity at 3 A g^(-1)after 1100 *** present incorporation of imide-linked covalent organic frameworks in the surface modification of ZMAs will offer fresh perspectives in the search for ideal protective films for the practicality of AZIBs.

关键词： Aqueous zinc ion batteries Zinc metal anodes Surface modification Covalent organic frameworks Imide linkage

Extending Structures for Gel'fand-Dorfman Bialgebras

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Acta Mathematica Sinica,English Series 2024年第2期40卷 619-638页

作者： jia jia WEN Yan Yong HONG School of Mathematics Hangzhou Normal UniversityHangzhou 311121P.R.China

Gel'fand-Dorfman bialgebra,which is both a Lie algebra and a Novikov algebra with some compatibility condition,appeared in the study of Hamiltonian pairs in completely integrable *** also emerged in the description of a class special Lie conformal algebras called quadratic Lie conformal *** this paper,we investigate the extending structures problem for Gel'fand-Dorfman bialgebras,which is equivalent to some extending structures problem of quadratic Lie conformal ***,given a Gel'fand-Dorfman bialgebra(A,o,[.,.]),this problem is how to describe and classify all Gel'fand-Dorfman bialgebra structures on a vector space E(A⊂E)such that(A,o,[.,.])is a subalgebra of E up to an isomorphism whose restriction on A is the identity *** by the theories of extending structures for Lie algebras and Novikov algebras,we construct an object gH2(V,A)to answer the extending structures problem by introducing the notion of a unified product for Gel'fand-Dorfman bialgebras,where V is a complement of A in *** particular,we investigate the special case when dim(V)=1 in detail.

关键词： Gel'fand-Dorfman bialgebra Lie conformal algebra Extending structures problem Novikovalgebra

Optical Space Time Pulse Position Modulation over Exponential Weibull Turbulence Channel

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Chinese Journal of Electronics 2024年第2期33卷 527-535页

作者： Yue ZHANG Huiqin WANG xuemei MA Minghua CAO Qingbin PENG School of Computer and Communication Lanzhou University of Technology School of Foreign Languages Lanzhou University of Technology

An optical space time pulse position modulation(OSTPPM) scheme is proposed to satisfy the communication requirement of high transmission rate and better reliability. For the OSTPPM scheme, an improved threshold judgment-based orthogonal matching pursuit(IT-OMP) algorithm with low-complexity and near optimal performance is proposed. The average bit error rate of OSTPPM-IT-OMP scheme is investigated over the exponential Weibull channel, and its analytical expression is verified via Monte Carlo simulation. With the same simulation parameters, the signal to noise ratio of(4,4,2)-OSTPPM-IT-OMP is respectively 3.75 d B and 8.5 d B better than that of spatial pulse position modulation(SPPM) scheme and generalized spatial pulse position modulation(GSPPM)scheme at a bit error rate of 1 × 10-3. With the same transmission bits per symbol, the computational complexity of(3,4,2)-OSTPPM-IT-OMP scheme is reduced by 90.47% and 75.4% compared with(16,4,2)-SPPM and(5,4,2)-GSPPM schemes, respectively.

关键词： Wireless communication Wireless sensor networks Monte Carlo methods Bit error rate Matching pursuit algorithms Adaptive optics Optical modulation

Mechanical Properties and Electronic Structures of M(M=Ti,V,Cr,Mn and Fe)Dopedβ-Si_(3)N_(4) from First-Principle

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Journal of Wuhan University of Technology(Materials Science) 2024年第3期39卷 639-644页

作者：龙敏黄福祥 XU Liangyu LI xuemei YANG Zhou LENG Yue MEI Shini School of Materials Science and Engineering Chongqing University of TechnologyChongqing 400054China

The structures,mechanical properties and electronic structures of M metals(M=Ti,V,Cr,Mn and Fe)dopedβ-Si_(3)N_(4) were investigated by First-principles calculations within *** calculated lattice parameters ofβ-Si_(3)N_(4) were consistent with previous *** cohesive energy and formation enthalpy show that initialβ-Si_(3)N_(4) has the highest structural *** calculated elastic constant and the Voigt-Reuss-Hill approximation indicate that elastic moduli ofβ-Si_(3)N_(4) are slightly reduced by M *** on Poisson’s and Pugh’s ratio,β-Si_(3)N_(4) is a ductile material and the toughness ofβ-Si_(3)N_(4) increases with M doping,and Fe doping exhibited the best *** results of density of states,charge distributions and overlapping populations indicate thatβ-Si_(3)N_(4) has the strong covalent and ionic bond strength between N and Si.

关键词： first-principles β-Si_(3)N_(4) mechanical properties electronic structure

Eco-physiological characteristics of Tetracentron sinense *** in response to different light intensities

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Journal of Forestry Research 2024年第3期35卷 29-44页

作者： Rong Wang Xueheng Lu Hongyan Han xuemei Zhang Yonghong Ma Qinsong Liu Xiaohong Gan Key Laboratoryof Southwest Wildlife Resources Conservation Ministry of EducationChina West Normal UniversityNanchong 637009People's Republic of China Institute of Plant Adaptation and Utilization in Southwest Mountain China West Normal UniversityNanchong 637009People's Republic of China Office of the People's Government of Yuexi County Yuexi County 616650Liangshan Yi Autonomous PrefecturePeople's Republic of China

The regeneration of Tetracentron sinense *** poor in the understory and in open areas due to the charac-teristics of natural regeneration of the species on forest edges and in *** is unclear whether different light intensities in various habitats affect eco-physiological characteristics of saplings and their natural *** this study,the light intensity in *** habitats was simulated by artificial shading(L1:100%NS(natural sunlight)in the open;L2:50%NS in a forest gap or edge;L3:10%NS in understory)to investigate differences in morphology,leaf structure,physiology,and photosynthesis of 2-year-old sap-lings,and to analyze the mechanism of light intensity on sapling *** differences were observed in morphology(including leaf area,and specific leaf area)under different light *** to L1 and L3,chloroplast structure in L2 was *** increasing time,superoxide dismutase(SOD)and catalase(CAT)activities in L2 became gradually higher than under the other light intensities,while malondialdehyde(MDA)content was *** decreased osmoregulation substance contents of leaves but increased *** results suggest that light intensities significantly affect the eco-physiological characteristics of *** saplings and they would respond most favorably at intermediate levels of light by optimizing eco-physiological ***,50%natural sunlight should be created to promote saplings establishment and population recovery of *** during in situ conservation,including sowing mature seeds in forest edges or gaps and providing appropriate shade protection for seedlings and saplings in the open.

关键词： Chloroplast ultrastructure Eco-physiological characteristics Light intensities Sapling establishment Tetracentron sinense Oliv

Comprehensive applicability evaluation of four precipitation products at multiple spatiotemporal scales in Northwest China

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Journal of Arid Land 2024年第9期16卷 1232-1254页

作者： WANG Xiangyu XU Min KANG Shichang LI xuemei HAN Haidong LI Xingdong School of Mathematics Lanzhou Jiaotong UniversityLanzhou 730070China Key Laboratory of Cryospheric Science and Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China Faculty of Geomatics Lanzhou Jiaotong UniversityLanzhou 730070China

Precipitation plays a crucial role in the water cycle of Northwest *** accurate precipitation data is crucial for regional water resource management,hydrological forecasting,flood control and drought ***,the applicability of multi-source precipitation products for long time series in Northwest China has not been thoroughly *** this study,precipitation data from 183 meteorological stations in Northwest China from 1979 to 2020 were selected to assess the regional applicability of four precipitation products(the fifth generation of European Centre for Medium-Range Weather Forecasts(ECMWF)atmospheric reanalysis of the global climate(ERA5),Global Precipitation Climatology Centre(GPCC),Climatic Research Unit gridded Time Series Version 4.07(CRU TS v4.07,hereafter CRU),and Tropical Rainfall Measuring Mission(TRMM))based on the following statistical indicators:correlation coefficient,root mean square error(RMSE),relative bias(RB),mean absolute error(MAE),probability of detection(POD),false alarm ratio(FAR),and equitable threat score(ETS).The results showed that precipitation in Northwest China was generally high in the east and low in the west,and exhibited an increasing trend from 1979 to *** with the station observations,ERA5 showed a larger spatial distribution difference than the other *** overall overestimation of multi-year average precipitation was approximately 200.00 mm and the degree of overestimation increased with increasing precipitation *** multi-year average precipitation of GPCC and CRU was relatively close to that of station *** trend of annual precipitation of TRMM was overestimated in high-altitude regions and the eastern part of Lanzhou with more *** the monthly scale,GPCC performed well but underestimated precipitation in the Tarim Basin(RB=-4.11%),while ERA5 and TRMM exhibited poor accuracy in high-altitude ***5 had a large bias(RB≥120.00%)in winter months

关键词： precipitation products the fifth generation of European Centre for Medium-Range Weather Forecasts(ECMWF)atmospheric reanalysis of the global climate(ERA5) Global Precipitation Climatology Centre(GPCC) Climatic Research Unit gridded Time Series(CRU TS) Tropical Rainfall Measuring Mission(TRMM) applicability evaluation Northwest China

Commutators of Fractional Maximal Functions on Orlicz Spaces over Non-Homogeneous Metric Spaces

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Journal of Mathematical Research with Applications 2024年第6期 782-794页

作者： Guanghui LU xuemei LI College of Mathematics and Statistics Northwest Normal University

Let （X,d,μ） be a non-homogeneous metric measure space satisfying the geometrically doubling condition and the upper doubling *** this setting,the authors prove that the commutator ■ formed by ■ and the fractional maximal function M（α）is bounded from Lebesgue spaces Lp（μ） into spaces Lq（μ）,where ■ for ■ and ■.Furthermore,the boundedness of the ■ on Orlicz spaces LΦ（μ） is established.

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Efficiency-first spraying mission arrangement optimization with multiple UAVs in heterogeneous farmland with varying pesticide requirements

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Information Processing in Agriculture 2024年第2期11卷 237-248页

作者： Yang Li Yanqiang Wu Xinyu Xue xuemei Liu Yang Xu Xinghua Liu Nanjing Institute of Agricultural Mechanization Ministry of Agriculture and Rural AffairsNanjing 210014PR China College of Mechanical&Electronic Engineering Shandong Agricultural UniversityTai'an 271018PR China Key Laboratory of Modern Agricultural Equipment Ministry of Agriculture and Rural AffairsNanjing 210014PR China Shandong Provincial Key Laboratory of Horticultural Machinery and Equipment Tai’an 271018PR China Shandong Provincial Engineering Laboratory of Agricultural Equipment Intellectualization Tai’an 271018PR China

Combining multiple crop protection Unmanned Aerial Vehicles(UAVs)as a team for a scheduled spraying mission over farmland now is a common way to significantly increase ***,given some issues such as different configurations,irregular borders,and especially varying pesticide requirements,it is more important and more complex than other multi-Agent Systems(MASs)in common *** this work,we focus on the mission arrangement of UAVs,which is the foundation of other high-level cooperations,systematically propose Efficiency-first Spraying Mission Arrangement Problem(ESMAP),and try to construct a united problem framework for the mission arrangement of crop protection ***,to characterise the differences in sub-areas,the varying pesticide requirement per unit is well considered based on Normalized Difference Vegetation Index(NDVI).Firstly,the mathematical model of multiple crop-protection UAVs is established and ESMAP is ***,an acquisition method of a farmland’s NDVI map is proposed,and the calculation method of pesticide volume based on NDVI is ***,an improved Genetic Algorithm(GA)is proposed to solve ESMAP,and a comparable combination algorithm is *** simulations for algorithm analysis are carried out within MATLAB,and it is determined that the proposed GA is more efficient and accurate than the ***,a mission arrangement tested with three UAVs was carried out to validate the effectiveness of the proposed GA in spraying *** results illustrated that it performed well,which took only 90.6%of the operation time taken by the combination algorithm.

关键词： Efficiency-first optimization Mission arrangement Multi-UAVs Heterogeneous farmland

Facile synthesis of transition metal complexes with five coplanar metal-carbon σ-bonds

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National Science Review 2024年第4期11卷 11-12页

作者： Guocheng jia Department of Chemistry Hong Kong University of Science and Technology

Carbon is one of the most important elements in chemistry, forming a vast number of organic compounds. It can also form a variety of organometallic compounds with a metal–carbon bond. Metal alkyl, carbene and carbyne complexes are classical examples of organometallic compounds. A particularly interesting class of organometallic compounds are all-carbon metallacycles formed by combination of a metal and a hydrocarbon chain serving as a chelating agent with only carbon atoms as the donor atoms. Many interesting monocyclic metallacycles made of a chelating bidentate hydrocarbon chain are known, for example, metallacyclobutadienes, metallacyclopentadienes and metallabenzenes[1].

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多失效模式混联生产线生产率估算

同济大学学报（自然科学版） 2017年第2期45卷 281-288页

作者：刘雪梅贾勇琪祁国栋邵焕同济大学机械与能源工程学院上海201804

针对存在多失效模式的混联生产线生产率估算问题,综合考虑机器的时间相关失效(TDF)和操作相关失效(ODF),分析了机器正常加工、TDF、ODF和TDF&ODF四种状态,建立了各状态间转移关系.基于连续时间马尔可夫链模型,以两工作站单缓冲区生产单... 详细信息

针对存在多失效模式的混联生产线生产率估算问题,综合考虑机器的时间相关失效(TDF)和操作相关失效(ODF),分析了机器正常加工、TDF、ODF和TDF&ODF四种状态,建立了各状态间转移关系.基于连续时间马尔可夫链模型,以两工作站单缓冲区生产单元为基础,结合生产线近似分解法及并行机器等效法,提出了一种多失效模式下混联生产线生产率估算方法.最后,通过多个算例的仿真对比及某生产线实例,验证了本文方法的准确性与高效性.

关键词：生产率估算混联生产线多失效模式马尔可夫链