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Tuning the porosity of {Co12IICo8III（μ3-Oh）24（X）}11+ supramolecular frameworks by reaction time for D2/h2 separation

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Science China Chemistry 2025年

作者： Zhuozhou Xie Zhu Zhuo Zi-ang Nan Qing Li Xiufang Li Zi-Xiu Lu Linzhe Lü Jin Liu Luyao Liu Wenjing Wang Wei Wang Daqiang Yuan You-Gui h.ang State Key Laboratory of Structure Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences University of Chinese Academy of Sciences Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials Xiamen Institute of Rare Earth Materials Haixi InstitutesChinese Academy of Sciences State Key Laboratory of Physical Chemistry of Solid Surfaces Department of Chemistry College of Chemistry and Chemical EngineeringXiamen University

Systematicly tuning the porosities of porous materials is crucial for targeted gas mixture separation,yet it remains a longstanding *** a common strategy,altering the phenylene ring count in the organic building units has been exploited to adjust pore apertures in metal organic frameworks （MOFs） and covalent organic frameworks （COFs）,resulting in only a stepwise pore size variation of approximately 2.8?.Unlike MOFs and COFs,the porosities for supramolecular assembly frameworks are highly dependent on the packings of the molecular building units in the *** above strategy cannot be applied to supramolecular assembly frameworks and other strategies are required to adjust pore apertures in supramolecular frameworks,especially to achieve porous materials with the optimal pore size for D2/h2separation （～3?）.here,we successfully modulate the porosity of supramolecular frameworks of[CoII1+12CoIII8L12（μ3-Oh）24（X）]1clusters （L=mono-deprotonated 1-iminoisoindole-3-amine,X=ClO?4or Cl?） by controlling the duration of self-assembly *** simply adjusting the reaction time,we obtain three[CoII12CoIII8L12（μ3-Oh）24（X）]11+supramolecular frameworks:[CoII12CoIII8（μ3-Oh）24（ClO4）L12)]·（Cl）4·（hCO2）7（1）,[CoII12CoIII8L12（μ3-Oh）24（Cl）]·（ClOI4）4·（Cl）6·（hCO2）·（h2O）10（2）,and[CoI12CoIII8L12（μ3-Oh）24（Cl）]·（Cl）11·（h2O）12（3）.The different stacking patterns of the[CoII12CoIII8L12（μ3-Oh）24（X）]11+clusters in these frameworks lead to significantly varied stabilities and *** 1 exhibits permanent porosity with interconnected channels and maintains stability under harsh *** contrast,compound 2 is nearly nonporous,and compound 3 becomes unstable upon *** pores of compound 1 show higher affinity to D2than h2,and the pore aperture diameter of compound 1 （～3.06?） meets the optimal porosity for D2/***,compound 1 demonstrates moderate D2/h2separation at 77 K (retention time:～7 min/g for D2/h2/Ne （10/10/80 vol%） in a flow of 5 mL

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A micromechanical model based on hypersingular integro-differential equations for analyzing micro-crazed interfaces between dissimilar elastic materials

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Applied Mathematics and Mechanics(English Edition) 2020年第2期41卷 193-206页

作者： X.Wang W.T.ang h.FAN School of Mechanical and Aerospace Engineering Nanyang Technological University50 Nanyang AvenueSingapore 639798Singapore

The current work models a weak(soft) interface between two elastic materials as containing a periodic array of micro-crazes. The boundary conditions on the interfacial micro-crazes are formulated in terms of a system of hypersingular integro-differential equations with unknown functions given by the displacement jumps across opposite faces of the micro-crazes. Once the displacement jumps are obtained by approximately solving the integro-differential equations, the effective stiffness of the micro-crazed interface can be readily computed. The effective stiffness is an important quantity needed for expressing the interfacial conditions in the spring-like macro-model of soft interfaces. Specific case studies are conducted to gain physical insights into how the effective stiffness of the interface may be influenced by the details of the interfacial micro-crazes.

关键词： micromechanical modeling micro-crazed interface effective stiffness coefficient hypersingular integro-differential equation

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highly Efficient and Stable hydrogen Production in All ph Range by Two-Dimensional Structured Metal-Doped Tungsten Semicarbides

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Research 2019年第1期2019卷 991-1004页

作者： Edison h.ang Khang N.Dinh Xiaoli Sun Ying h.ang Jun Yang Zhili Dong Xiaochen Dong Wei h.ang Zhiguo Wang hua Zhang Qingyu Yan Energy Research Institute Interdisciplinary Graduate SchoolNanyang Technological University637553Singapore Centre for Programmable Materials School of Materials Science and EngineeringNanyang Technological University639798Singapore Institute of Advanced Materials Nanjing Tech UniversityNanjing 210000China School of Physical Electronics University of Electronic Science and Technology of ChinaChengdu 610054China Department of Chemistry City University of Hong KongKowloonHong Kong

Transition-metal-doped tungsten semicarbide nanosheets(M-doped W_(2)C NSs,M=Fe,Co,and Ni)have been synthesized through carburization of the mixture of tungsten trioxide,polyvinylpyrrolidone,and metal *** nanosheets grow directly on the W mesh and have the lateral dimension of several hundreds of nm to a few�m with a thickness of few tens *** is demonstrated that the M-doped W_(2)C NSs exhibit superior electrocatalytic activity for hydrogen evolution reaction(hER).Impressively,the Nidoped W_(2)C NSs(2 at%Ni)with the optimized hER activity show extremely low onset overpotentials of 4,9,and 19 mV and modest Tafel slopes of 39,51,and 87 mV dec−1 in acidic(ph=0),neutral(ph=7.2),and basic(ph=14)solutions,respectively,which is close to the commercial Pt/C *** functional theory(DFT)calculations also demonstrate that the Gibbs free energy for h adsorption of Ni-W_(2)C is much closer to the optimal valueG_(h∗)=-0.073 eV as compared to-0.16 eV of W_(2)***,nearly 100%Faradaic efciency and long-term stability are obtained in those *** realization of highly tolerant metal semicarbide catalyst performing on par with commercial Pt/C in all range of ph ofers a key step towards industrially electrochemical water splitting.

关键词： highly closer realization

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Precise asymptotics in the law of the logarithm for random fields in hilbert space

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第4期8卷 651-659页

作者： FU Ke-ang Zhang Li-xin Department of Mathematics Zhejiang University Hangzhou 310027 China

Consider the positive d-dimensional lattice Z^d（d≥2） with partial ordering ≤, let {XK; K∈Z＋^d} be i.i.d, random variables taking values in a real separable hilbert space （h, ｜｜·｜｜） with mean zero and covariance operator ∑ and set partial sums SN =∑K≤nXK,K,N∈Z＋^d. Under some moment conditions, we obtain the precise asymptotics of a kind of weighted infinite series for partial sums SN as ε↓ by using the truncation and approximation methods. The results are related to the convergence rates of the law of the logarithm in hilbert space, and they also extend the results of （Gut and Spataru, 2003）.

关键词： The law of the logarithm Random field hilbert space. Tail probabilitv. Truncation method

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Precise Rates in the Law of the Logarithm for the Moment Convergence in hilbert Spaces

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Acta Mathematica Sinica,English Series 2009年第2期25卷 191-208页

作者： Ke ang FU Li Xin Zhang Department of Mathematics Zhejiang University Hangzhou 310027 P. R. China School of Statistics and Mathematics Zhejiang Gongshang University Hangzhou 310035 P. R. China

Let （X, Xn; n ≥1） be a sequence of i.i.d, random variables taking values in a real separable hilbert space （h, ｜｜·｜｜） with covariance operator ∑. Set Sn = X1 ＋ X2 ＋ ... ＋ Xn, n≥ 1. We prove that, for b 〉 -1, lim ε→0 ε^2（b＋1） ∞ ∑n=1 （logn）^b/n^3/2 E{｜｜Sn｜｜-σε√nlogn}=σ^-2（b＋1）/（2b＋3）（b＋1） B｜｜Y｜^2b＋3holds if EX=0,and E｜｜X｜｜^2（log｜｜x｜｜）^3bv（b＋4）〈∞ where Y is a Gaussian random variable taking value in a real separable hilbert space with mean zero and covariance operator ∑, and σ^2 denotes the largest eigenvalue of ∑.

关键词： the law of the logarithm moment convergence tail probability strong approximation

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Contributions of adsorption, bioreduction and desorption to uranium immobilization by extracellular polymeric substances

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Frontiers of Environmental Science & Engineering 2023年第9期17卷 125-135页

作者： Chen Zhou Ermias Gebrekrstos Tesfamariam Youneng Tang ang Li Biodesign Swette Center for Environmental Biotechnology Arizona State UniversityTempeAZ 85281USA Department of Civil and Environmental Engineering FAMU-FSU College of EngineeringFlorida State UniversityTallahasseeFL 32310USA State Key Laboratory of Urban Water Resource and Environment School of EnvironmentHarbin Institute of TechnologyHarbin 150090China

hexavalent uranium(U(VI))can be immobilized by various *** role of extracellular polymeric substances(EPS)in U(VI)immobilization has not been *** work provides a model framework to quantify the contributions of three processes involved in EPS-mediated U(VI)immobilization:adsorption,bioreduction and *** associated EPS was extracted from a pure bacterial strain,Klebsiella sp.J1,and then exposed to h_(2) and O_(2)(no bioreduction control)to immobilize U(VI)in batch experiments.U(VI)immobilization was faster when exposed to h_(2) than O_(2) and stabilized at 94%for h_(2) and 85%for O_(2),*** non-equilibrium data from the h_(2) experiments were best simulated by a kinetic model consisting of pseudo-second-order adsorption(ka=2.87×10^(−3) g EPS·(mg U)^(−1)·min^(−1)),first-order bioreduction(kb=0.112 min−1)and first-order desorption(kd=7.00×10^(−3) min^(−1))and fitted the experimental data with R^(2) of *** adsorption was dominant in the first minute of the experiments with h_(2),bioreduction was dominant from the second minute to the 50th *** 50 min,adsorption was negligible,and bioreduction was balanced by *** work also provides the first set of equilibrium data for U(VI)adsorption by EPS *** equilibrium experiments with O_(2) were well simulated by both the Langmuir isotherm and the Freundlich isotherm,suggesting multiple mechanisms involved in the interactions between U(VI)and *** thermodynamic study indicated that the adsorption of U(VI)onto EPS was endothermic,spontaneous and favorable at higher temperatures.

关键词： Adsorption Bioreduction Desorption Kinetics Isotherm Uranium

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Modeling and flapping vibration suppression of a novel tailless flapping wing micro air vehicle

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Chinese Journal of Aeronautics 2022年第3期35卷 309-328页

作者： Siqi Wang Bifeng SONG ang ChEN Qiang FU Jin CUI School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China Yangtze River Delta Research Institute of Northwestern Polytechnical University Taicang 215400China Research&Development Institute of Northwestern Polytechnical University in shenzhen Shenzhen 518057China School of Aeronautic Science and Engineering Beihang UniversityBeijing 100083China

This paper establishes and analyzes a high-fidelity nonlinear time-periodic dynamic model and the corresponding state observer for flapping vibration suppression of a novel tailless Flapping Wing Micro Air Vehicle(FWMAV),named ***,a complete modeling of NPU-Tinybird is determined,including the aerodynamic model based on the quasi-steady method,the kinematic and dynamic model about the mechanism of flapping and attitude control,combined with the single rigid body dynamic *** on this,a linearized longitudinal pitch dynamic cycle-averaged model is obtained and analyzed through the methods of neural network fitting and system identification,preparing for the design of flapping vibration suppression *** vibration is an inherent property of the tailless FWMAV,which arises from the influence of time-periodic aerodynamic forces and *** can be captured by attitude and position sensors on the plane,which impairs the flight performance and efficiency of flight controller and *** deal with this problem,a novel state observer for flapping vibration suppression is designed.A robust optimal controller based on the linear quadratic theory is also designed to stabilize the closed-loop *** results are given to verify the performance of the observer,including the closed loop responses combined with robust optimal controller,the comparison of different parameters of observer and the comparison with several classic methods,such as Kalman filter,h-infinity filter and low-pass filter,which prove that the novel observer owns a fairly good suppression effect on flapping vibration and benefits for the improvement of flight performance and control efficiency.

关键词： Flapping vibration Flapping wing Linear quadratic theory Robust control State observer

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GAAF:Searching Activation Functions for Binary Neural Networks Through Genetic Algorithm

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Tsinghua Science and Technology 2023年第1期28卷 207-220页

作者： Yanfei Li Tong Geng Samuel Stein ang Li huimin Yu Department of Information Science and Electronic Engineering Zhejiang UniversityHangzhou 310027China h Pacific Northwest National Laboratory RichlandWA 99354USA

Binary neural networks(BNNs)show promising utilization in cost and power-restricted domains such as edge devices and mobile *** is due to its significantly less computation and storage demand,but at the cost of degraded *** close the accuracy gap,in this paper we propose to add a complementary activation function(AF)ahead of the sign based binarization,and rely on the genetic algorithm(GA)to automatically search for the ideal *** AFs can help extract extra information from the input data in the forward pass,while allowing improved gradient approximation in the backward *** novel AFs are identified through our GA-based search,while most of them show improved performance(up to 2.54%on ImageNet)when testing on different datasets and network ***,periodic functions are identified as a key component for most of the discovered AFs,which rarely exist in human designed *** method offers a novel approach for designing general and application-specific BNN *** will be released on Github.

关键词： binary neural networks(BNNs) genetic algorithm activation function

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Effects of osmotic stress on the expression profiling of aquaporin genes in the roughskin sculpin(Trachidermus fasciatus)

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Acta Oceanologica Sinica 2020年第6期39卷 19-25页

作者： Qian Ma Xinfu Liu ang Li shufang Liu Zhimeng Zh.ang College of Fisheries Guangdong Ocean UniversityZhanjiang 524088China Yellow Sea Fisheries Research Institute Chinese Academy of Fishery SciencesQingdao 266071China

Aquaporins(AQPs)are a family of integral membrane proteins that have been shown to be important for osmoregulation in many *** identify potential stress resistance-related aqp genes in salinity adaptation of the roughskin sculpin Trachidermus fasciatus,we investigated the time-course expression dynamics of seven aquaporin genes(aqp1,4,7,8,10,11 and 12)in three osmoregulatory tissues(kidney,gill and intestine)and one metabolic tissue(liver).The fish were subjected to two different acute osmotic treatments(seawater-tofreshwater transfer respectively achieved in 1 h and 24 h,namely,E-acute and acute group).The expression profiling of the seven aqp genes were performed using quantitative real-time PCR(qRT-PCR).At the time of all sampling time points(0 h,12 h,24 h and 48 h),no expression of aqp4 was found in the gill,liver and intestine;no expression of aqp7 was found in the gill and *** differences of aqp expression were determined in the four target tissues,and the mRNA levels were largely variable among gene members and *** patterns of the time-course expression were detected in most of the aqp genes in *** between the two acute groups,except that only one gene(aqp12)in the kidney and three genes(aqp7,aqp8 and aqp10)in the intestine revealed different expression *** results suggest that the expression response of aqp genes was similar under osmotic changes with different rates.

关键词： Trachidermus fasciatus aquaporin salinity changes stress response gene expression

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Oxidation Modification of Polyacrylonitrile-Based Carbon Fiber and Its Electro-Chemical Performance as Marine Electrode for Electric Field Test

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Journal of Ocean University of China 2020年第2期19卷 361-368页

作者： ZAI Xuerong LIU ang TIAN Yuhua ChAI Fanggang FU Yubin College of Chemistry and Chemical Engineering Ocean University of ChinaQingdao 266100China School of Materials Science and Engineering Ocean University of ChinaQingdao 266100China

A novel sensor for ocean electric field testing has been fabricated by polyacrylonitrile-based on carbon fibers with electro-chemical *** surface profile characteristics of the carbon fibers were characterized by scanning electron microscope,Fourier transform infrared spectra and contact *** voltammetry and Tafel curves have been used to study its electro-chemical *** identical electrodes in sea water as the electric field sensor will swiftly respond to applied electric field which causes positive and negative ions to move in opposite direction,resulting in a electric potential difference(ΔE).Test result indicates that the offset potential is typically below 1 m V with a drift of 60-170μVd^-*** self noise level is 1.07 nV√hz^(1/2)@1 *** electric field response indicates that the modified electrode pair shows better response to AC sine signal of amplitude and frequency(5 mV and 1 mhz)respectively than its *** electric field response model of the modified electrodes is creatively presented according to its electric double layer capacitance and Faraday *** advantages of the carbon fiber electric field electrode will make it have potential application prospect.

关键词： carbon fiber electrode electro-chemical oxidation modification electro-chemical performance electric field response electric field test

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