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Double Moving Extremes Ranked Set Sampling Design

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 75-90页

作者： Meng Chen Wang-xue Chen Rui Yang department of mathematics and Statistics Jishou UniversityJishou416000China

The traditional simple random sampling(SRS)design method is inefficient in many *** proposed some new designs to increase *** this paper,as a variation of moving extremes ranked set sampling(MERSS),double MERSS(DMERSS)is proposed and its properties for estimating the population mean are *** turns out that,when the underlying distribution is symmetric,DMERSS gives unbiased estimators of the population ***,it is found that DMERSS is more efficient than the SRS and MERSS methods for usual symmetric distributions(normal and uniform).For asymmetric distributions considered in this study,the DMERSS has a small bias and it is more efficient than SRS for usual asymmetric distribution(exponential)for small sample sizes.

关键词： double moving extremes ranked set sampling symmetric distribution efficiency

Intelligent laser-induced graphene sensor for multiplex probing catechol isomers

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Chinese Chemical Letters 2024年第7期35卷 227-234页

作者： Tian Cao Xuyin Ding Qiwen Peng Min Zhang Guoyue Shi School of Chemistry and Molecular Engineering Shanghai Key Laboratory for Urban Ecological Processes and Eco-RestorationEast China Normal UniversityShanghai 200241China

Herein,we unveil the intelligent detection of multiple catechol isomers in complex environments utilizing both laser-induced graphene(LIG)and artificial neural network(ANN).The large scale-up manufacturing of LIG-based sensors(LIGS)with three-electrode configuration on polyimide(PI)is achieved by direct laser-writing and screen-printing *** LIGS shows excellent electrochemical performance toward catechol isomers,i.e.,hydroquinone(1,4-dihydroxybenzene,HQ),catechol(1,2-dihydroxybenzene,CT),and resorcinol(1,3-dihydroxybenzene,RC),with a low limit of detection(LOD)(CC,0.079μmol/L;HQ,0.093μmol/L;RC,1.18μmol/L).Moreover,the ANN model is developed for machine-intelligent to predict concentrations of catechol isomers under an interfering environment via a single *** six unique parameters extracted from the differential pulse voltammetry(DPV)response,the machine learning-based regression provides a coefficient of correlation with 0.998 and is able to correctly predict the total and individual concentrations in complex river ***,this work provides a guide for the preparation and application of LIGS via facile and cost-efficient mass production and the development of an intelligent sensing platform based on the ANN model.

关键词： Laser-induced graphene Phenolic pollutants Electrochemical detection Artificial neural network

Precise Asymptotics in Limit Theorems for a Supercritical Branching Process with Immigration in a Random Environment

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Acta Mathematica Sinica,English Series 2024年第8期40卷 1850-1874页

作者： Chun Mao HUANG Rui ZHANG Zhi Qiang GAO department of mathematics Harbin Institute of Technology(Weihai)Weihai 264209P.R.China School of Mathematical Sciences Beijing Normal UniversityBeijing 100875P.R.China

Let(Zn)be a supercritical branching process with immigration in an independent and identically distributed random *** necessary moment conditions,we show the exact convergence rate in the central limit theorem on log Zn and establish the corresponding local limit theorem by using the moments of the natural submartingale and the convergence rates of its *** similar approach and with the help of a change of measure,we also present the so-called integrolocal theorem and integral large deviation theorem to characterize the precise asymptotics of the upper large deviations.

关键词： Branching process with immigration random environment central limit theorem large deviation

THE ABSENCE OF SINGULAR CONTINUOUS SPECTRUM FOR PERTURBED JACOBI OPERATORS

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Acta Mathematica Scientia 2024年第2期44卷 515-531页

作者：傅钲淇黎雄 department of Basic Sciences Naval Submarine AcademyQingdao266199China Laboratory of mathematics and Complex Systems(Ministry of Education) School of Mathematical SciencesBeijing Normal UniversityBeijing100875China

This paper is mainly about the spectral properties of a class of Jacobi operators(H_(c,b)u)(n)=c_(n)u(n+1)+c_(n-1)u(n-1)+b_(n)u(n),.where∣c_(n)−1∣=O(n^(−α))and b_(n)=O(n^(−1)).We will show that,forα≥1,the singula... 详细信息

关键词： Jacobi operator singular continuous spectrum Prüfer variables

Engineering Cu_(2)O/Cu/N-C interface to induce directional migration of charge for driving photocatalytic homo-coupling of terminal alkynes

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Nano Research 2024年第8期17卷 6895-6902页

作者： Xiaoqin Yan Tianyi Xu Wenwen Zhan Yang Yang Yang Yu Jianjian Yi Xiaoxiao He Lei Yang Jianwei Zhao Liming Sun Xiguang Han Jiangsu Key Laboratory of Green Synthetic Chemistry for Functional Materials Department of ChemistrySchool of Chemistry&Materials ScienceJiangsu Normal UniversityXuzhou 221116China State Key Laboratory of Precision Spectroscopy East China Normal UniversityShanghai 200241China College of Environmental Science and Engineering Yangzhou UniversityYangzhou 225009China Shenzhen HUASUAN Technology Co. LtdShenzhen 518055China

The efficient utilization of visible light catalysts for organic reactions necessitates not only the effective separation of photogenerated electrons and holes to participate in the reaction,but also their ability to form key intermediates with reactant *** present study successfully synthesized a crusiform-like mesoporous structure of nitrogen-doped carbon-coated Cu_(2)O/Cu(Cu_(2)O/Cu/N-C)with a Cu_(2)O/dual electron acceptor interface using etched HKUST-1 as the precursor.A series of theoretical and experimental studies have demonstrated that the Cu_(2)O/Cu/N-C interface in the photocatalytic homo-coupling of terminal alkynes not only effectively enhances the separation of photogenerated electron−hole pairs,but also facilitates the formation of the key intermediate[Cu_(2)O/Cu/N-C]-phenylacetylide and promotes the rearrangement of its internal *** a result,the homo-coupling reaction can be effectively *** primary reason for the functional role of Cu_(2)O/Cu/N-C interface lies in the downward bending of energy band from Cu_(2)O to N-doped C layers,induced by the different work functions of Cu_(2)O,Cu and N-doped C ***,Cu_(2)O/Cu/N-C photocatalysts demonstrate exceptional photocatalytic activity in the homo-coupling reaction of terminal alkynes under blue-light irradiation and air *** present study presents a novel research methodology for the development of highly efficient visible light catalysts to facilitate organic reactions in future applications.

关键词： photocatalysis homo-coupling of terminal alkynes directional migration of charges heterojunction interface Cu_(2)O carbon coated

Derivatives of Intersection Local Time for Two Independent Symmetricα-stable Processes

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Acta Mathematica Sinica,English Series 2024年第5期40卷 1273-1292页

作者： Huan ZHOU Guang Jun SHEN Qian YU department of mathematics Anhui Normal UniversityWuhu 241002P.R.China department of mathematics Nanjing University of Aeronautics and AstronauticsNanjing 211106P.R.China Key Laboratory of Mathematical Modelling and High Performance Computing of Air Vehicles(NUAA) MIITNanjing 211106P.R.China

In this paper,we consider the derivatives of intersection local time for two independent d-dimensional symmetricα-stable processes X^(α) and X^(α)with respective indices α and α.We first study the sufficient condition for the existence of the derivatives,which makes us obtain the exponential integrability and H?lder *** we show that this condition is also necessary for the existence of derivatives of intersection local time at the ***,we also study the power variation of the derivatives.

关键词： Symmetric stable processes intersection local time exponential integrability power variation

Positive Solutions of Second Order Discrete Problem on Infinite Intervals

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Journal of Mathematical Research with Applications 2024年第4期44卷 511-520页

作者： Haiyi WU Tianlan CHEN department of mathematics Northwest Normal University

In this paper,by using the discrete Arzelá-Ascoli Lemma and the fixed-point theorem in cones,we discuss the existence of positive solutions of the following second order discrete Sturm-Liouville boundary value problem on infinite intervals■where?u(x)=u(x+1)-u(x) is the forward difference operator,■is continuous,a>0,B and C are nonnegative constants,■

关键词： positive solutions second order discrete problems infinite intervals fixed-point theorem in cones

A combined Liouville integrable hierarchy associated with a fourth-order matrix spectral problem

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Communications in Theoretical Physics 2024年第7期76卷 1-8页

作者： Wen-Xiu Ma department of mathematics Zhejiang Normal UniversityJinhua 321004China department of mathematics King Abdulaziz UniversityJeddah 21589Saudi Arabia department of mathematics and Statistics University of South Florida TampaFL 33620-5700United States of America Material Science Innovation and Modelling Department of Mathematical SciencesNorth-West UniversityMafikeng CampusMmabatho 2735South Africa

This paper aims to propose a fourth-order matrix spectral problem involving four potentials and generate an associated Liouville integrable hierarchy via the zero curvature formulation.A bi-Hamiltonian formulation is furnished by applying the trace identity and a recursion operator is explicitly worked out,which exhibits the Liouville integrability of each model in the resulting *** specific examples,consisting of novel generalized combined nonlinear Schrodinger equations and modified Korteweg-de Vries equations,are given.

关键词： integrable hierarchy Hamiltonian structure zero curvature equation Lax pair matrix spectral problem

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Existence of Solutions for Systems of k-Dimensional Minkowski-Curvature Problems with Neumann Conditions

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Journal of Mathematical Research with Applications 2024年第1期44卷 35-42页

作者： Tianlan CHEN Yali ZHAO Haiyi WU department of mathematics Northwest Normal University

We prove the existence of solutions of the system for nonlocal Neumann problems with Minkowski-curvature operator■,where k,N≥1 are integers,f:[0,1]×Rk→Rkis continuous and g:[0,1]→Rkis a function of bounded *** pr... 详细信息

关键词： Minkowski-curvature operator Perturbation method Neumann problem solutions