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Gradient‑Layered MXene/Hollow Lignin Nanospheres Architecture Design for flexible and Stretchable Supercapacitors

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Nano-Micro Letters 2025年第2期17卷 447-462页

作者： Haonan Zhang Cheng Hao Tongtong fu Dian Yu jane Howe Kaiwen Chen Ning Yan Hao Ren Huamin zhai jiangsu Provincial Key Lab of Sustainable Pulp and Paper Technology and Biomass Materials NanJing Forestry UniversityNanjing 210037People’s Republic of China Department of Chemical Engineering and Applied Chemistry University of Toronto200 College StreetTorontoON M5S 3E5Canada Department of Materials Science and Engineering University of Toronto184 College StreetTorontoON M5S 3E4Canada College of Materials Science and Engineering Nanjing Forestry UniversityNanjing 210037People’s Republic of China

With the rapid development of flexible wearable electronics,the demand for stretchable energy storage devices has *** this work,a novel gradient-layered architecture was design based on single-pore hollow lignin nanospheres(HLNPs)-intercalated two-dimensional transition metal carbide(Ti_(3)C_(2)T_(x) MXene)for fabricating highly stretchable and durable *** depositing and inserting HLNPs in the MXene layers with a bottom-up decreasing gradient,a multilayered porous MXene structure with smooth ion channels was constructed by reducing the overstacking of MXene ***,the micro-chamber architecture of thin-walled lignin nanospheres effectively extended the contact area between lignin and MXene to improve ion and electron accessibility,thus better utilizing the pseudocapacitive property of *** these strategies effectively enhanced the capacitive performance of the *** addition,HLNPs,which acted as a protective phase for MXene layer,enhanced mechanical properties of the wrinkled stretchable electrodes by releasing stress through slip and deformation during the stretch-release cycling and greatly improved the structural integrity and capacitive stability of the *** electrodes and symmetric flexible all-solid-state supercapacitors capable of enduring 600%uniaxial tensile strain were developed with high specific capacitances of 1273 mf cm^(−2)(241 f g^(−1))and 514 mf cm^(−2)(95 f g^(−1)),***,their capacitances were well preserved after 1000 times of 600%stretch-release *** study showcased new possibilities of incorporating biobased lignin nanospheres in energy storage devices to fabricate stretchable devices leveraging synergies among various two-dimensional nanomaterials.

关键词： Hollow lignin nanospheres MXene Gradient-layered architecture Wrinkled electrodes Stretchable supercapacitors

资源支持、组织能力与价值创造:社区互助养老服务可持续生产的驱动路径

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海南大学学报（人文社会科学版） 2025年第1期43卷 107-118页

作者：翟绍果韩煜西北大学公共管理学院陕西西安710127

社区互助养老服务何以可持续生产,基于“环境-组织-价值”分析框架,以我国37个社区互助养老典型案例为样本,运用模糊集定性比较分析方法;(fsQCA)探究社区互助养老服务可持续生产的组态驱动路径。研究表明:;(1)外部支持、社区资源、主体... 详细信息

社区互助养老服务何以可持续生产,基于“环境-组织-价值”分析框架,以我国37个社区互助养老典型案例为样本,运用模糊集定性比较分析方法;(fsQCA)探究社区互助养老服务可持续生产的组态驱动路径。研究表明:;(1)外部支持、社区资源、主体协同、制度化水平、技术赋能与价值创造通过组态效应影响社区互助养老服务的可持续生产;(2)外部支持与社区资源、制度化水平与技术赋能具有潜在替代性,社区资源和价值创造是组态形成的关键因素;(3)党政统合型、社区自组织型、技术嵌入型和协同驱动型是驱动社区互助养老服务可持续生产的4种优化路径。实现社区互助养老服务高水平的可持续生产应坚持系统联动思维,释放多元组态的复合驱动效应,重视社区资源和价值创造的关键作用,选择适宜不同地区发展基础的互助养老模式。

关键词：社区互助养老可持续生产驱动路径

维普期刊数据库博看期刊

THE VALIDITY Of THE MODIfIED MORI-TANAKA METHOD fOR COMPOSITES WITH SLIGHTLY WEAKENED INTERfACE

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Acta Mechanica Solida Sinica 1997年第2期10卷 108-117页

作者： zhai, j Luo, HA SHANGHAI jIAO TONG UNIV DEPT ENGN MECHSHANGHAI 200030PEOPLES R CHINA

This paper presents a direct Mori-Tanaka approach to calculate the effective moduli of particle-reinforced composites and fiber-reinforced composites with spring-like imperfect interfaces. By a comparison between these results and those obtained from the approximate Mori-Tanaka method developed by Qu for composites with slightly weakened interface, the validity of the Qu's method is revealed.

关键词： composite materials imperfect interface effective moduli Mori-Tanaka method

Angular velocity determination of spinning solar sails using only a sun sensor

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Chinese journal of Aeronautics 2017年第1期30卷 412-418页

作者： zhai Kun School of Aerospace Engineering Tsinghua University Beijing 100084 China

The direction of the sun is the easiest and most reliable observation vector for a solar sail running in deep space exploration. This paper presents a new method using only raw measurements of the sun direction vector to estimate angular velocity for a spinning solar sail. In cases with a constant spin angular velocity, the estimation equation is formed based on the kinematic model for the apparent motion of the sun direction vector; the least-squares solution is then easily calculated. A performance criterion is defined and used to analyze estimation accuracy. In cases with a variable spin angular velocity, the estimation equation is developed based on the kinematic model for the apparent motion of the sun direction vector and the attitude dynamics equation. Simulation results show that the proposed method can quickly yield high-precision angular velocity estimates that are insensitive to certain measurement noises and modeling errors.

关键词： Condition number Least-squares method Solar sail Spinning Velocity determination

Cutting Characteristics of Zr-Based Bulk Metallic Glass

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journal of Materials Science & Technology 2015年第2期31卷 153-158页

作者： D.X.Han G.Wang j.Li K.C.Chan S.To f.f.Wu Y.L.Gao Q.j.zhai Laboratory for Microstructures Shanghai University Department of Industrial and System Engineering The Hong Kong Polytechnic University

Cutting behavior exerts a considerable influence on the fabrication of bulk metallic glass(BMG) components. In this study,the influences of machining parameters(i.e.,depth of cutting,feed rate,and spindle rate) on the turned surface of a Zr-based BMG after observing the 3D morphologies of this surface were *** results showed that the influence of the spindle rate on the surface morphologies is more substantial as compared to the depth of cutting and the feed rate. Nanoscratch tests were conducted to further characterize the separation mechanism of the chips,which revealed that the chips are torn off the surface of a BMG because of inhomogeneous localized maximum shear stress.

关键词： Bulk metallic glass Ultra-precision machining Surf

STUDY ON NANOMETER ZINC PARTICLES fABRICATED BY GAS EVAPORATION METHOD

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Acta Metallurgica Sinica(English Letters) 2003年第3期16卷 161-168页

作者： A.A.A.Saleh X.j.zhai Y.C.zhai Y.fu A.L.Zhang School of Materials and Metallurgy Northeastern UniversityShenyang110004ChinaSchool of Materials and MetallurgyNortheastern UniversityShenyang110004ChinaSchool of Materials and MetallurgyNortheastern UniversityShenyang110004ChinaSchool of Materials and MetallurgyNortheastern UniversityShenyang110004ChinaSchool of Materials and MetallurgyNortheastern UniversityShenyang110004China

Nanometer Zn particles with mean diameters 12-100nm made by evaporating its powders in argon gas were studied mainly by X-ray diffraction and electron microscopy. They are collected at various distances and those factors influencing the mean particle size were studied. The optimal synthetic conditions were obtained, i.e., evaporation temperature is 1200℃; argon flow rate is 0.4m3/h; amount of powder charged is 3g; distance from evaporation source is 10cm. It was found that the size of particles was governed by argon flow rate, evaporation temperature, amount of metal charged and distance from the source. The size increases remarkably with distance in the space where no metal vapor exists. This implies that the crystallites grow by coalescence. Electron micrographs and diffraction patterns are reproduced to show the size, shape and state of oxidations. Nanoparticles with definite crystal habits were sometimes observed among those with irregular ones.

关键词： gas evaporation method nanometer Zn XRD TEM

Multi-stage crustal growth and cratonization of the North China Craton

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Geoscience frontiers 2014年第4期5卷 457-469页

作者： Mingguo zhai State Key Laboratory of Continental Geodynamics Northwest University Key Laboratory of Mineral Resources Institute of Geology and GeophysicsChinese Academy of Sciences

The North China Craton（NCC） has a complicated evolutionary history with multi-stage crustal growth,recording nearly all important geological events in the early geotectonic history of the *** studies propose that the NCC can be divided into six micro-blocks with ＆gt;～3.0-3.8 Ga old continental nuclei that are surrounded by Neoarchean greenstone belts（CRB）.The micro-blocks are also termed as highgrade regions（HGR） and are mainly composed of orthogneisses with minor gabbros and BIf-bearing supracrustal beds or lenses,all of which underwent strong deformation and metamorphism of granulite- to high-grade *** micro-blocks are,in turn,from east to west,the jiaoliao（jL）,Qianhuai（QH）,Ordos（ODS）,ji’ning（jN） and Alashan（ALS） blocks,and Xuchang（XCH） in the *** studies led to a consensus that the basement of the NCC was composed of different blocks/terranes that were finally amalgamated to form a coherent craton at the end of *** U-Pb data show that TTG gneisses in the HGRs have two prominent age peaks at ca.2.9-2.7 and2.6-2.5 Ga which may correspond to the earliest events of major crustal growth in the *** isotopic model ages range from ca.3.8 to 2.5 Ga and mostly are in the range of 3.0-2.6 Ga with a peak at2.82 *** studies revealed a much larger volume of TTG gneisses in the NCC than previously considered,with a dominant ca.2.7 Ga magmatic zircon *** of the ca.2.7 Ga TTG gneisses underwent metamorphism in 2.6-2.5 Ga as indicated by ubiquitous metamorphic rims around the cores of magmatic zircon in these *** ca.2.6-2.5 Ga orthogneisses have Hf-in-zircon and Nd wholerock model ages mostly around 2.9-2.7 Ga and some around 2.6-2.5 Ga,indicating the timing of protolith formation or extraction of the protolith magma was from the ***,it is suggested that the 2.6-2.5 Ga TTGs probably represent a coherent event of continental accretion and major reworking（crustal melting）.As a distinct charac

关键词： Crustal growthMulti-stageCratonizationNCC

On Some Sums Involving Small Arithmetic functions

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Acta Mathematica Sinica,English Series 2024年第10期40卷 2497-2518页

作者： Wen Guang zhai Department of Mathematics China University of Mining and TechnologyBeijing 100083P.R.China

Let f be any arithmetic function and define S_(f)(x):=Σ_(n≤x)f([x/n]).If the function f is small,namely,f(n)﹤﹤n^(ε),then the error term E_(f)(x)in the asymptotic formula of S_f(x)has the form O(x^(1/2+ε)).In this paper,we shall study the mean square of E_(f)(x)and establish some new results of E_(f)(x)for some special functions.

关键词： Small arithmetic function exponential sum asymptotic formula

DCVAE-adv:A Universal Adversarial Example Generation Method for White and Black Box Attacks

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Tsinghua Science and Technology 2024年第2期29卷 430-446页

作者： Lei Xu junhai zhai College of Mathematics and Information Science Hebei UniversityBaoding 071002China

Deep neural network(DNN)has strong representation learning ability,but it is vulnerable and easy to be fooled by adversarial *** order to handle the vulnerability of DNN,many methods have been *** general idea of existing methods is to reduce the chance of DNN models being fooled by observing some designed adversarial examples,which are generated by adding perturbations to the original *** this paper,we propose a novel adversarial example generation method,called *** from the existing methods,DCVAE-adv constructs adversarial examples by mixing both explicit and implicit perturbations without using original ***,the proposed method can be applied to both white box and black box *** addition,in the inference stage,the adversarial examples can be generated without loading the original images into memory,which greatly reduces the memory *** compared DCVAE-adv with three most advanced adversarial attack algorithms:fGSM,AdvGAN,and AdvGAN++.The experimental results demonstrate that DCVAE-adv is superior to these state-of-the-art methods in terms of attack success rate and transfer ability for targeted *** code is available at https://***/xzforeverlove/DCVAE-adv.

关键词： deep neural network adversarial examples white box attack black box attack robustness