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Surface embedded binary Co-Cu hydroxy phosphate over surface of oxy/hydroxides for efficient nitrate reduction to ammonia

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Nano Research 2025年第1期18卷 195-207页

作者： Chun Zhu yifei Yang yike Jing Zhen Zeng Xuesong yi Wei sun Fei Yang Key Laboratory of Agro-Forestry Environmental Processes and Ecological Regulation of Hainan Province School of Environmental Science and EngineeringHainan UniversityHaikou 570228China

Electrochemical nitrate reduction reaction(NO3RR)to ammonia is a promising approach to address excess Ncontamination in aqueous environment but suffers from a limited ammonia yield and selectivity due to the low concentration and sluggish *** work reports a three-dimensional porous electrode with binary Co_(2)Cu_(1)hydroxy phosphate embedded into the surface of Ni_(3)Co_(1)oxy/hydroxides(CoCu-PH@NiCo/Ni,“PH”means phosphate-hydroxide),which delivers a yield of 4.13 mg·h^(-1)·cm^(-2)with a high Faraday efficiency of 92.6%under a low nitrate concentration of 40 mM and provide an impressive *** embedded structure of the as-prepared catalyst exhibits unique metal coordination ligands and valence states different from the unitary *** electrochemical in situ infrared spectra and theoretical calculations revealed that the Co sites with the ability to dissociate water molecular to form adsorbed OH*can effectively provide the required protons for the deoxygenation and hydrogenation steps during NO3-conversion,thereby,effectively reducing the energy barrier of the key transition states in the NO3RR process to improve the intrinsic *** demonstrate that the rational design of binary components with the appropriate ability to activate water molecules as well as the threedimensional porous skeletal structure are expected to promote effectively the low-concentration nitrates conversion to ammonia.

关键词： nitrate reduction hydroxy phosphate surface embedded water dissociation active hydroxy adsorbed

Robust Adaptive Control for Robotic Systems With Input Time-Varying Delay Using Hamiltonian Method

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IEEE/CAA Journal of Automatica Sinica 2018年第4期5卷 852-859页

作者： yong Ren Weiwei sun Institute of Automation Qufu Normal UniversityQufu 273165China School of Engineering Qufu Normal UniversityRizhao 276826China

This paper addresses the problem of robust adaptive control for robotic systems with model uncertainty and input time-varying delay. The Hamiltonian method is applied to develop the stabilization results of the robotic systems. Firstly, with the idea of shaping potential energy and the pre-feedback skill, the n degree-of-freedom(DOF) uncertain robotic systems are realized as an augmented dissipative Hamiltonian formulation with ***, based on the obtained Hamiltonian system formulation and by using of the Lyapunov-Krasovskii(L-K) functional method, an adaptive controller is designed to show that the robotic systems can be asymptotically stabilized depending on the input delay. Meanwhile, some sufficient conditions are spelt out to guarantee the rationality and validity of the proposed control law. Finally, study of an illustrative example with simulations shows that the controller obtained in this paper works very well in handling uncertainties and input delay in the robotic systems.

关键词： Adaptive controller Hamiltonian systems input delay Lyapunov-Krasovskii(L-K) functional robotic systems

Statistical description of depth-dependent turbulent velocity measured in Taihu Lake, China

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Water Science and Engineering 2018年第3期11卷 243-249页

作者： Lin Yuan Hong-guang sun yong Zhang yi-ping Li Bing-qing Lu State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University College of Mechanics and Materials Hohai University Department of Geological Sciences University of Alabama College of Environment Hohai University

Quantitative description of turbulence using simple physical/mathematical models remains a challenge in classical physics and hydrologic dynamics. This study monitored the turbulence velocity field at the surface and bottom of Taihu Lake, in China, a large shallow lake with a heterogeneous complex system, and conducted a statistical analysis of the data for the local turbulent structure. Results show that the measured turbulent flows with finite Reynolds numbers exhibit properties of non-Gaussian distribution. Compared with the normal distribution, the Levy distribution with meaningful parameters can better characterize the tailing behavior of the measured turbulence. Exit-distance statistics and multiscaling extended self-similarity(ESS) were used to interpret turbulence dynamics with different scale structures. Results show that the probability density function of the reverse structure distance and the multiscaling ESS can effectively capture the turbulent flow dynamics varying with water depth. These results provide an approach for quantitatively analyzing multiscale turbulence in large natural lakes.

关键词： Finite Reynolds number turbulence Reverse structure function Levy distribution Probability density function Multiscaling extended self-similarity(ESS)

Probing the interaction between asphaltene-wax and its effects on the crystallization behavior of waxes in heavy oil via molecular dynamics simulation

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Petroleum Science 2024年第4期21卷 2839-2848页

作者： yong Hu Xi Lu Hai-Bo Wang Ji-Chao Fang yi-Ning Wu JianFang sun SINOPEC Petroleum Exploration and Production Research Institute Beijing102206China Shandong Key Laboratory of Oilfield Chemistry School of Petroleum EngineeringChina University of Petroleum(East China)Qingdao266580ShandongChina

High content of asphaltenes and waxes leads to the high pour point and the poor flowability of heavy oil,which is adverse to its efficient development and its transportation in *** the interaction mechanism between asphaltene-wax is crucial to solve these problems,but it is still *** this paper,molecular dynamics simulation was used to investigate the interaction between asphaltenewax and its effects on the crystallization behavior of waxes in heavy *** show that molecules in pure wax are arranged in a paralleled *** wax molecules in heavy oil,which are close to the surface of asphaltene aggregates,are bent and arranged *** the mass fraction of asphaltenes in asphaltene-wax system(ω_(asp))is 0-25 wt%,the attraction among wax molecules decreases and the bend degree of wax molecules increases with the increase ofω_(asp).Theω_(asp)increases from 0 to 25 wt%,and the attraction between asphaltene-wax is stronger than that among *** causes that the wax precipitation point changes from 353 to 333 *** theω_(asp)increases to 50 wt%,wax molecules are more dispersed owing to the steric hindrance of asphaltene aggregates,and the interaction among wax molecules transforms from attraction to *** causes that the ordered crystal structure of waxes can't be formed at normal ***,the asphaltene,with the higher molecular weight or the more hetero atoms,has more obvious inhibition to the formation of wax ***,resins also have an obvious inhibition on the wax crystal due to the formation of asphalteneresin aggregates with a larger *** results reveal the interaction mechanism between asphaltene-wax,and provide useful guidelines for the development of heavy oil.

关键词： Heavy oil Interaction mechanism Asphaltenes Waxes Molecular dynamics

Rapid fabrication of modular 3D paper-basedmicrofluidic chips using projection-based 3D printing

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Bio-Design and Manufacturing 2024年第5期7卷 611-623页

作者： Mingjun Xie Zexin Fu Chunfei Lu Sufan Wu Lei Pan yong He yi sun Ji Wang Plastic and Reconstructive Surgery Center Department of Plastic and Reconstructive SurgeryZhejiang Provincial People’s HospitalAffiliated People’s HospitalHangzhou Medical CollegeHangzhou 310014China State Key Laboratory of Fluid Power and Mechatronic Systems School of Mechanical EngineeringZhejiang UniversityHangzhou 310058China Key Laboratory of Materials Processing and Mold Zhengzhou UniversityZhengzhou 450002China Key Laboratory of 3D Printing Process and Equipment of Zhejiang Province College of Mechanical EngineeringZhejiang UniversityHangzhou 310058China Cancer Center Zhejiang UniversityHangzhou 310058China

Paper-based microchips have different advantages,such as better biocompatibility,simple production,and easy handling,making them promising candidates for clinical diagnosis and other *** study describes amethod developed to fabricate modular three-dimensional(3D)paper-based microfluidic chips based on projection-based 3D printing(PBP)technology.A series of two-dimensional(2D)paper-based microfluidic modules was designed and *** evaluating the effect of exposure time on the accuracy of the flow channel,the resolution of this channel was experimentally ***,several 3D paper-based microfluidic chips were assembled based on the 2D ones using different methods,with good channel ***-based 2D and hydrogel-based 3D cell culture systems based on 3D paper-based microfluidic chips were verified to be ***,by combining extrusion 3D bioprinting technology and the proposed 3D paper-based microfluidic chips,multiorgan microfluidic chips were established by directly printing 3D hydrogel structures on 3D paperbased microfluidic chips,confirming that the prepared modular 3D paper-based microfluidic chip is potentially applicable in various biomedical applications.

关键词： Paper-based microfluidic chip Projection-based 3D printing(PBP) Modularization Cell culture

Existence and multiplicity of positive solutions for an elastic beam equation

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Applied Mathematics(A Journal of Chinese Universities) 2011年第3期26卷 253-264页

作者： sun yong-ping College of Electron and Information Zhejiang University of Media and Communications Hangzhou310018 China.

This paper investigates the boundary value problem for elastic beam equation of the formu″″（t） q（t）f（t, u（t）,u′（t）,u″（t）,u′″（t））, 0〈t〈1,with the boundary conditionsu=（0）=u′（1）=u″（0）=u′″（1）=0.The boundary conditions describe the deformation of an elastic beam simply supported at left and clamped at right by sliding clamps. By using Leray-Schauder nonlinear alternate, Leray-Schauder fixed point theorem and a fixed point theorem due to Avery and Peterson, we establish some results on the existence and multiplicity of positive solutions to the boundary value problem. Our results extend and improve some recent work in the literature.

关键词： Positive solution existence and multiplicity elastic beam equation fixed point theorem nonlinear alternate.

Three Symmetric Positive Solutions for Second-order Nonlocal Boundary Value Problems

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Acta Mathematicae Applicatae Sinica 2011年第2期27卷 233-242页

作者： yong-ping sun College of Electron and Information Zhejiang University of Media and Communications Hangzhou 310018China

Using the Leggett-Williams fixed point theorem, we will obtain at least three symmetric positive solutions to the second-order nonlocal boundary value problem of the form u″（t）＋g（t）f（t,u（t））=0,0〈t〈1,u（0）=u（1）=∫01m（s）u（s）ds. where m ∈ L1[0 1], g ：（0, 1）→ [0, ∞） is continuous, symmetric on （0, 1） and maybe singular at t = 0 and t = 1, f： [0, 1] × [0, ∞） → [0, ∞） is continuous and f（-, x） is symmetric on [0, 1] for all x∈ [0, ∞）.

关键词： symmetric positive solution nonlocal boundary value problem fixed point theorem

Monotone positive solution for three-point boundary value problem

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Applied Mathematics(A Journal of Chinese Universities) 2008年第3期23卷 279-285页

作者： sun yong-ping College of Electronics and Information Zhejiang University of Media and Communications Hangzhou310018 China

In this paper, the existence of monotone positive solution for the following secondorder three-point boundary value problem is studied：x″（t）＋f（t,x（t））=0,0〈t〈1,x′（0）=0,x（1）＋δx′（η）=0,where η ∈ （0, 1）, δ∈ [0, ∞）, f ∈ C（[0, 1] × [0, ∞）, [0, ∞））. Under certain growth conditions on the nonlinear term f and by using a fixed point theorem of cone expansion and compression of functional type due to Avery, Anderson and Krueger, sufficient conditions for the existence of monotone positive solution are obtained and the bounds of solution are given. At last, an example is given to illustrate the result of the paper.

关键词： three-point boundary value problem fixed point theorem monotone positive solution

Existence and iteration of monotone positive solutions for a third-order two-point boundary value problem

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Applied Mathematics(A Journal of Chinese Universities) 2008年第4期23卷 413-419页

作者： sun yong-ping School of Electronics and Information Zhejiang University of Media and Communications Hangzhou 310018 China

The existence of nondecreasing positive solutions for the nonlinear third-order twopoint boundary value problem u′″（t）＋ q（t）f（t,u（t）,u′（t）） = 0, 0 〈 t 〈 1, u（0） = u″（0） = u′（1） = 0 is studied.... 详细信息

关键词： third-order two-point boundary value problem monotone iterative method positive solution,existence iterative scheme