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Journal of Computational Mathematics 2024年第2期42卷 337-354页

作者： Wansheng wang Department of Mathematics Shanghai Normal UniversityShanghai 200234China

Stability and global error bounds are studied for a class of stepsize-dependent linear multistep methods for nonlinear evolution equations governed by ω-dissipative vector fields in Banach *** break through the order barrier p≤1 of unconditionally contractive linear multistep methods for dissipative systems,strongly dissipative systems are *** employing the error growth function of the methods,new contractivity and convergence results of stepsize-dependent linear multistep methods on infinite integration intervals are provided for strictly dissipative systems(ω<0)and strongly dissipative *** applications of the main results to several linear multistep methods,including the trapezoidal rule,are *** theoretical results are also illustrated by a set of numerical experiments.

关键词： Nonlinear evolution equation Linear multistep methods ω-dissipative operators Stability Convergence Banach space

On Existence of the Even L_(p)Gaussian Minkowski Problem for p>n

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Chinese Annals of Mathematics,Series B 2024年第2期45卷 179-192页

作者： Hejun wang School of Mathematics and Statistics Shandong Normal UniversityJi'nan 250014China

This paper concerns the even L_(p)Gaussian Minkowski problem in n-dimensional Euclidean space R^(n).The existence of the solution to the even L_(p)Guassian Minkowski problem for p>n is obtained.

关键词： Convex body Existence L_(p)Gaussian surface area measure The even L_(p)Gaussian Minkowski problem

Nonclassical correlations in two-dimensional graphene lattices

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Communications in Theoretical Physics 2024年第4期76卷 72-79页

作者： Hao wang Shanghai Normal University Tianhua College ShangHai 201815China

We investigate nonclassical correlations via negativity,local quantum uncertainty(LQU)and local quantum Fisher information(LQFI)for two-dimensional graphene *** explicitly analytical expressions for negativity,LQU and LQFI are *** close forms of LQU and LQFI confirm the inequality between the quantum Fisher information and skew information,where the LQFI is always greater than or equal to the LQU,and both show very similar behavior with different ***,the effects of the different system parameters on the quantified quantum correlation are *** LQFI reveals more nonclassical correlations than LQU in a two-dimensional graphene lattice system.

关键词： negativity local quantum uncertainty(LQU) local quantum Fisher information(LQFI) graphene lattices nonclassical correlations

Numerical three-dimensional modeling of earthen dam piping failure

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Water Science and Engineering 2024年第1期17卷 72-82页

作者： Zhengang wang Independent Researcher HerndonVA 20171USA

A physically-based numerical three-dimensional earthen dam piping failure model is developed for homogeneous and zoned soil *** model is an erosion model,coupled with force/moment equilibrium *** flow and two-dimensional(2D)shallow water equations(SWE)are solved to simulate dam break flows at different breaching *** rates of different soils with different construction compaction efforts are calculated using corresponding erosion *** dam's real shape,soil properties,and surrounding area are *** outer 2D-SWE grids are used to control upstream and downstream hydraulic conditions and control the boundary conditions of orifice flow,and inner 2D-SWE flow is used to scour soil and perform force/moment equilibrium *** model is validated using the European Commission IMPACT(Investigation of Extreme Flood Processes and Uncertainty)Test#5 in Norway,Teton Dam failure in Idaho,USA,and Quail Creek Dike failure in Utah,*** calculated peak outflows are within 10%errors of observed *** results show that,for a V-shaped dam like Teton Dam,a piping breach location at the abutment tends to result in a smaller peak breach outflow than the piping breach location at the dam's center;and if Teton Dam had broken from its center for internal erosion,a peak outflow of 117851 m'/s,which is 81%larger than the peak outflow of 65120 m3/s released from its right abutment,would have been released from Teton Dam.A lower piping inlet elevation tends to cause a faster/earlier piping breach than a higher piping inlet elevation.

关键词： 3D dam breach model 2D shallow water equations 3D slope stability analysis Piping failure Teton Dam Quail Creek Dike

Light People: Professor Fanglin Bao and his cover story

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Light(Science & Applications) 2024年第6期13卷 1015-1020页

作者： Ji wang School of Science Westlake UniversityHangzhouZhejiangPR China

Qu Yuan,a renowned ancient Chinese poet,once pondered in his work Heavenly Inquiry:“If the sun’s light is absent,from where does the radiance of the Hero Flower emanate?”The ability to see clearly in the darkest of nights has long been a sought-after magical power by *** holds not only immense technological significance for computer vision and remote sensing but also profound implications for transcending the dichotomy between day and night in our daily *** Fanglin Bao from Westlake University has made significant breakthroughs in this field,bringing us closer to a world where we can transform night into *** groundbreaking research on Heat-Assisted Detection and Ranging(HADAR)and night vision was featured as the cover story in Nature on July 26,2023.

关键词： bringing breakthrough holds

Predict the spatiotemporal distribution of solar magnetic field and understand the evolutionary feature of solar activity

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Science China Earth Sciences 2024年第8期67卷 2702-2704页

作者： Jingxiu wang National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China

Solar activities are closely related to human production and daily *** warm sunlight nurtures life on Earth,but the Sun also occasionally exhibits eruptive activities that significantly impact and threaten the Earth’s *** eruptive activities occur as large-scale energy release processes in localized regions of the solar atmosphere,primarily manifested through the enhanced electromagnetic radiation and energetic particle emissions in solar flares,as well as the ejection of mass and magnetic flux in coronal mass ejections(CMEs).

关键词： Solar Earth evolutionary

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The effect of salt anion in ether‐based electrolyte for electrochemical performance of sodium‐ion batteries:A case study of hard carbon

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Carbon Energy 2024年第8期6卷 285-297页

作者： Jiabao Li Jingjing Hao Quan Yuan Ruoxing wang Frederick Marlton Tianyi wang Chengyin wang Xin Guo Guoxiu wang College of Chemistry and Chemical Engineering Yangzhou UniversityYangzhouJiangsuChina School of Mathematical and Physical Sciences Centre for Clean Energy TechnologyFaculty of ScienceUniversity of Technology SydneySydneyAustralia

Compared with the extensively used ester‐based electrolyte,the hard carbon(HC)electrode is more compatible with the ether‐based counterpart in sodium‐ion batteries,which can lead to improved cycling stability and robust rate ***,the impact of salt anion on the electrochemical performance of HC electrodes has yet to be fully *** this study,the anionic chemistry in regulating the stability of electrolytes and the performance of sodium‐ion batteries have been systematically *** work shows discrepancies in the reductive stability of the anionic group,redox kinetics,and component/structure of solid electrolyte interface(SEI)with different salts(NaBF_(4),NaPF_(6),and NaSO_(3)CF_(3))in the typical ether solvent(diglyme).Particularly,the density functional theory calculation manifests the preferred decomposition of PF_(6)−due to the reduced reductive stability of anions in the solvation structure,thus leading to the formation of NaF‐rich *** investigation on redox kinetics reveals that the NaPF_(6)/diglyme can induce the fast ionic diffusion dynamic and low charge transfer barrier for HC electrode,thus resulting in superior sodium storage performance in terms of rate capability and cycling life,which outperforms those of NaBF_(4)/diglyme and NaSO_(3)CF_(3)/***,this work offers valuable insights for optimizing the electrochemical behaviors of electrode materials by regulating the anionic group in the electrolyte.

关键词： ether‐based electrolyte reaction kinetics salt anion SEI components sodium storage

Natural forests exhibit higher organic carbon concentrations and recalcitrant carbon proportions in soil than plantations:a global data synthesis

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Journal of Forestry Research 2024年第5期35卷 131-141页

作者： Xiuqing Nie Hui wang Jian wang Shirong Liu Ecology and Nature Conservation Institute Chinese Academy of ForestryKey Laboratory of Forest Ecology and Environment of National Forestry and Grassland AdministrationNo.2 DongxiaofuHaidian DistrictBeijing 100091People’s Republic of China

Different chemical compositions of soil organic carbon(SOC)affect its persistence and whether it signifi-cantly differs between natural forests and plantations remains *** synthesizing 234 observations of SOC chemical compositions,we evaluated global patterns of concentra-tion,individual chemical composition(alkyl C,O-alkyl C,aromatic C,and carbonyl C),and their distribution *** results indicate a notably higher SOC,a markedly larger proportion of recalcitrant alkyl C,and lower easily decomposed carbonyl C proportion in natural ***-ever,SOC chemical compositions were appreciably more evenly distributed in *** on the assumed con-ceptual index of SOC chemical composition evenness,we deduced that,compared to natural forests,plantations may have higher possible resistance to SOC decomposition under *** tropical regions,SOC levels,recalcitrant SOC chemical composition,and their distributed evenness were significantly higher in natural forests,indicating that SOC has higher chemical stability and possible resistance to *** factors had minor effects on alkyl C in forests globally,while they notably affected SOC chemi-cal composition in tropical *** could contribute to the differences in chemical compositions and their distrib-uted evenness between plantations and natural stands.

关键词： Global data synthesis Natural forest Plantations Soil organic carbon Soil organic carbon chemical composition

Boring holes in Au nanoplates by active surface etching

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Nano Research 2024年第9期17卷 8610-8617页

作者： Haiyang Hu Yuntao wang Qian wang Xudong Peng An Su Hong wang Hongyu Chen Institute of Advanced Synthesis(IAS)and School of Chemistry and Molecular Engineering Jiangsu National Synergetic Innovation Centre for Advanced MaterialsNanjing Tech UniversityNanjing 211816China Department of Environmental Science and Engineering University of Science and Technology of ChinaHefei 230026China Department of Chemistry School of Science and Key Laboratory for Quantum Materials of Zhejiang ProvinceResearch Center for Industries of the FutureWestlake UniversityHangzhou 310030China Institute of Natural Sciences Westlake Institute for Advanced StudyHangzhou 310024China

In contrast to the conventional etching that makes nanoparticles rounder and our previous sharpening etching mode that causes serrated edges,here,we developed a new boring etching mode that targets the faces of Au nanoplates to make *** critical factors are the pre-incubation step with the ligand 2-mercapto-5-benzimidazolecarboxylic acid(MBIA)and the subsequent removal of excess ligands in the ***,etching is focused onto the few sites with initial loss of ligands,which cannot be quickly *** choice of ligand MBIA is also of importance,as it carries negative charge and repels each *** inability of forming a dense layer probably plays a critical role in the site-selectivity for faces,because ligands at the higher curvature edges and corners are expected to have less *** etching results from the comproportionation reaction between Au3+and Au0 in the nanoplates,where Br-coordination to Au and the extra stabilization from cetyltrimethylammonium bromide(CTAB)are *** believe that the ability of boring holes is an important tool for future synthetic designs.

关键词： Au nanoplates active surface etching boring etching mode cetyltrimethylammonium bromide(CTAB)passivation holes

Underwater Pulse Waveform Recognition Based on Hash Aggregate Discriminant Network

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Journal of Ocean University of China 2024年第3期23卷 654-660页

作者： wang Fangchen ZHONG Guoqiang wang Liang College of Computer Science and Technology Ocean University of ChinaQingdao 266100China College of Marine Technology Ocean University of ChinaQingdao 266100China

Underwater pulse waveform recognition is an important method for underwater object *** existing works focus on the application of traditional pattern recognition methods,which ignore the time-and space-varying characteristics in sound propagation channels and cannot easily extract valuable waveform *** propagation channels in seawater are time-and space-varying convolutional *** the extraction of the waveform features of underwater acoustic signals,the effect of high-accuracy underwater acoustic signal recognition is identified by eliminating the influence of time-and space-varying convolutional channels to the greatest extent *** propose a hash aggregate discriminative network(HADN),which combines hash learning and deep learning to minimize the time-and space-varying effects on convolutional channels and adaptively learns effective underwater waveform features to achieve high-accuracy underwater pulse waveform *** the extraction of the hash features of acoustic signals,a discrete constraint between clusters within a hash feature class is *** constraint can ensure that the influence of convolutional channels on hash features is *** addition,we design a new loss function called aggregate discriminative loss(AD-loss).The use of AD-loss and softmax-loss can increase the discriminativeness of the learned hash *** results show that on pool and ocean datasets,which were collected in pools and oceans,respectively,by using acoustic collectors,the proposed HADN performs better than other comparative models in terms of accuracy and mAP.

关键词： convolutional channel hash aggregate discriminative network aggregate discriminant loss waveform recognition