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Interfacial Zn2+-solvation regulator towards reversible and stable Zn anode

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Journal of Energy Chemistry 2025年第1期100卷 684-692页

作者： Miao Zhou Xiongbin Luo Hang Li shan Guo Zhuang tong Xiaotao Zhou Xu Li Zhaohui Hou Shuquan Liang Guozhao Fang College of Mechanical Engineering Key Laboratory of Hunan Province for Advanced Carbon-based Functional Materials Hunan Institute of Science and Technology School of Materials Science and Engineering Key Laboratory of Electronic Packaging and Advanced Functional Materials of Hunan Province Central South University College of Materials and Metallurgy Guizhou University National Energy Metal Resources and New Materials Key Laboratory Central South University

Aqueous zinc-ion batteries （AZIBs） are fundamentally challenged by the instability of the electrode/electrolyte interface,predominantly due to irreversible zinc （Zn） deposition and hydrogen ***,the intricate mechanisms behind the electrochemical discrepancies induced by interfacial Zn2+-solvation and deposition behavior demand comprehensive *** molecules endowed with special functional groups （such as hydroxyl,carboxyl,etc.） have the potential to significantly optimize the solvation structure of Zn2+and regulate the interfacial electric double layer （EDL）.By increasing nucleation overpotential and decreasing interfacial free energy,these functional groups facilitate a lower critical nucleation radius,thereby forming an asymptotic nucleation model to promote uniform Zn ***,this study presents a pioneering approach by introducing trace amounts of n-butanol as solvation regulators to engineer the homogenized Zn （H-Zn） anode with a uniform and dense *** interfacial reaction and structure evolution are explored by in/ex-situ experimental techniques,indicating that the H-Zn anode exhibits dendrite-free growth,no by-products,and weak hydrogen evolution,in sharp contrast to the bare ***,the H-Zn anode achieves a remarkable Zn utilization rate of approximately 20% and simultaneously sustains a prolonged cycle life exceeding 500 ***,the H-Zn//NH4V4O10（NVO） full battery showcases exceptional cycle stability,retaining 95.04%capacity retention after 400 cycles at a large current density of 5 A *** study enlightens solvation-regulated additives to develop Zn anode with superior utilization efficiency and extended operational lifespan.

关键词： Solvation

南天区5 GHz VLBI成图普查的一些统计研究

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天体物理学报 1998年第2期19卷 137-141页

作者：沈志强万同山中国科学院上海天文台

本文发表对已完成的两轮南天区５ＧＨｚＶＬＢＩ成图普查观测的统计研究．在简要总结两轮观测结果的基础上，将它们分别与ＰｅａｒｓｏｎＲｅａｄｈｅａｄ（ＰＲ）普查样本源和Ｗｅｈｒｌｅ等人普查的变源。

关键词：河外射电源 VLBI 普查统计分析南天区成图

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无中导洞连拱隧道掌子面纵向间距优化

科学技术与工程 2022年第21期22卷 9355-9363页

作者：王永东柏文军陈媛媛刘洋万善通长安大学公路学院西安710064

作为一种大跨径地下结构形式连拱隧道结构复杂,无中导洞法能在提高施工速度的基础上降低中隔墙渗漏水。为研究连拱隧道无中导洞法施工活动对隧道先后行洞的影响程度,以陈家滩隧道为研究对象,通过数值模拟研究了不同间距下先后行洞的影... 详细信息

作为一种大跨径地下结构形式连拱隧道结构复杂,无中导洞法能在提高施工速度的基础上降低中隔墙渗漏水。为研究连拱隧道无中导洞法施工活动对隧道先后行洞的影响程度,以陈家滩隧道为研究对象,通过数值模拟研究了不同间距下先后行洞的影响范围、先后行洞的影响程度以及中隔墙的倾覆趋势。结果表明:当先行洞开挖至控制截面5 m范围内时,对围岩的影响最大,其围岩位移释放系数增量达到了40%以上;超过控制截面10 m时其围岩释放系数达到了93%以上,影响程度较小;超过20 m时影响程度可以忽略。当先后行洞纵向间距大于35 m时,影响程度接近10%,纵向间距大于40 m时,影响程度小于10%。从中隔墙的倾覆程度来看,当先行洞开挖完成时,中隔墙的倾斜程度达到最大,倾斜度约为3.28×10^(-4);而纵向间距大于30 m时倾斜度差值为0.351×10^(-4),此时中隔墙倾斜程度较大极差较小,有利于中隔墙受力。故先后行洞开挖掌子面纵向间距建议控制在30~40 m。

关键词：公路隧道连拱隧道无中导洞法开挖面纵向间距

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软弱围岩隧道锁脚微型桩支护结构研究

公路 2022年第1期67卷 349-355页

作者：聂玉文万善通李国安刘晓王永东广东省交通规划设计研究院股份有限公司广州市510507 长安大学公路学院西安市710064

针对软弱围岩隧道施工过程中存在的支护变形、围岩坍塌等问题,提出一种锁脚微型桩支护结构。运用理论分析手段,阐述了锁脚微型桩的承载作用和注浆加固作用,改善了软弱围岩和支护结构的应力状态,充分发挥了初期支护的承载作用,抑制了隧... 详细信息

针对软弱围岩隧道施工过程中存在的支护变形、围岩坍塌等问题,提出一种锁脚微型桩支护结构。运用理论分析手段,阐述了锁脚微型桩的承载作用和注浆加固作用,改善了软弱围岩和支护结构的应力状态,充分发挥了初期支护的承载作用,抑制了隧道变形。依托其古顶隧道,采用现场试验的手段,分别对围岩压力、钢拱架应力、拱顶下沉和周边收敛变化特征与规律进行研究。研究结果表明:隧道开挖对拱顶和左右拱腰位置影响较大,其围岩压力分布值最大;同等软弱围岩地质条件下施作锁脚微型桩支护结构,隧道钢拱架应力增大了20%~40%,隧道拱顶下沉和周边收敛量减小约30%~40%左右。施作锁脚微型桩支护结构可提高围岩稳定性,增加支护刚度,减小围岩变形,使得初期支护效果得到提升。

关键词：隧道工程软弱围岩锁脚微型桩作用机理现场试验

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Multi-face detection based on downsampling and modified subtractive clustering for color images

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第1期8卷 72-78页

作者： KONG wan-zeng ZHU shan-an School of Electrical Engineering Zhejiang University Hangzhou 310027 China

This paper presents a multi-face detection method for color images. The method is based on the assumption that faces are well separated from the background by skin color detection. These faces can be located by the proposed method which modifies the subtractive clustering. The modified clustering algorithm proposes a new definition of distance for multi-face detection, and its key parameters can be predetermined adaptively by statistical information of face objects in the image. Downsampling is employed to reduce the computation of clustering and speed up the process of the proposed method. The effectiveness of the proposed method is illustrated by three experiments.

关键词： Multi-face detection Skin color Modified subtractive clustering Downsampling

An R(x)-orthonormal theory for the vibration performance of a non-smooth symmetric composite beam with complex interface

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Acta Mechanica Sinica 2019年第1期35卷 228-241,I0007页

作者： Chein-shan Liu Bo-tong Li College of Mechanics and Materials Hohai UniversityNanjing 210098China Center of Excellence for Ocean Engineering Department of Mechanical and Mechatronic EngineeringTaiwan Ocean UniversityKeelung 202-24China School of Mathematics and Physics University of Science and Technology BeijingBeijing 100083China

A composite beam is symmetric if both the material property and support are symmetric with respect to the middle point. In order to study the free vibration performance of the symmetric composite beams with different complex nonsmooth/discontinuous interfaces, we develop an R(x)-orthonormal theory, where R(x) is an integrable flexural rigidity function. The R(x)-orthonormal bases in the linear space of boundary functions are constructed, of which the second-order derivatives of the boundary functions are asked to be orthonormal with respect to the weight function R(x). When the vibration modes of the symmetric composite beam are expressed in terms of the R(x)-orthonormal bases we can derive an eigenvalue problem endowed with a special structure of the coefficient matrix A :=[aij ],aij= 0 if i + j is odd. Based on the special structure we can prove two new theorems, which indicate that the characteristic equation of A can be decomposed into the product of the characteristic equations of two sub-matrices with dimensions half lower. Hence, we can sequentially solve the natural frequencies in closed-form owing to the specialty of A. We use this powerful new theory to analyze the free vibration performance and the vibration modes of symmetric composite beams with three different interfaces.

关键词： Symmetric composite beams R(x)-orthogonality of second-order derivatives of boundary functions R(x)-orthonormal theory Non-smooth/discontinuous interface Sequentially closed-from natural frequencies

Whole-lifetime Coordinated Service Strategy for Battery Energy Storage System Considering Multi-stage Battery Aging Characteristics

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Journal of Modern Power Systems and Clean Energy 2022年第3期10卷 689-699页

作者： Feilong Fan Yan Xu Rui Zhang tong wan IEEE Energy Research Institute@NTU Nanyang Technological UniversitySingapore College of Smart Energy Shanghai Jiao Tong UniversityShanghaiChina School of Electrical and Electronic Engineering Nanyang Technological UniversitySingapore The University of New South Wales SydneyAustralia University of Sydney SydneyAustralia

One battery energy storage system(BESS)can be used to provide different services,such as energy arbitrage(EA)and frequency regulation(FR)support,etc.,which have different revenues and lead to different battery degradation *** paper proposes a whole-lifetime coordinated service strategy to maximize the total operation profit of BESS.A multi-stage battery aging model is developed to characterize the battery aging rates during the whole *** the uncertainty of electricity price in EA service and frequency deviation in FR service,the whole problem is formulated as a twostage stochastic programming *** the first stage,the optimal service switching scheme between the EA and FR services are formulated to maximize the expected value of the whole-lifetime operation *** the second stage,the output power of BESS in EA service is optimized according to the electricity price in the hourly timescale,whereas the output power of BESS in FR service is directly determined according to the frequency deviation in the second *** above optimization problem is then converted as a deterministic mixed-integer nonlinear programming(MINLP)model with bilinear *** Cormick envelopes and a bound tightening algorithm are used to solve *** simulation is carried out to validate the effectiveness and advantages of the proposed strategy.

关键词： Battery energy storage system(BESS) wholelifetime coordinated service multi-stage battery aging model two-stage stochastic programming mixed-integer nonlinear programming(MINLP)

Sufficient Conditions for Maximally Edge-Connected Hypergraphs

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Journal of the Operations Research Society of China 2021年第1期9卷 119-129页

作者： Lin-Ken tong Er-Fang shan Department of Mathematics Shanghai UniversityShanghai 200444China School of Management Shanghai UniversityShanghai 200444China

The edge-connectivity of a graph or a hypergraph is defined as the minimum number of edges whose removal renders the graph or hypergraph disconnected.A graph or hypergraph is called maximally edge-connected if the edge-connectivity equals its minimum *** this paper,we show that some classical sufficient conditions for graphs to be maximally edge-connected can be generalized to hypergraphs.

关键词： Hypergraph Edge-connectivity Maximally edge-connected

Positive Solutions for Second-Order m-Point Boundary Value Problems on Time Scales

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Acta Mathematica Sinica,English Series 2006年第6期22卷 1797-1804页

作者： wan tong LI Hong Rui SUN School of Mathematics and Statistics Lanzhou University Lanzhou 730000 P. R. China

Let T be a time scale such that 0, T ∈ T. By means of the Schauder fixed point theorem and analysis method, we establish some existence criteria for positive solutions of the m-point boundary value problem on time scales where α ∈ Ctd（（O,T,[0,∞））,f∈ Ckd（[0,∞）×[0,∞））,β,γ ∈[0,∞）,ξi ∈（0,p（T）.b,ai∈ （0,∞）（for i = 1,..., m - 2） are given constants satisfying some suitable hypotheses. We show that this problem has at least one positive solution for sufficiently small b 〉 0 and no solution for sufficiently large b. Our results are new even for the corresponding differential equation （T = R） and difference equation （T = Z）.

关键词： time scales positive solution Schauder fixed point theorem