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Analysis of relative error in detection caused by signal-induced noise in Na lidar system

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Science China Earth Sciences 2018年第1期61卷 109-118页

作者： ZHANG YunPeng YI fan kong Wei School of Electronic Information Wuhan University

Signal-induced noise(SIN) in a photomultiplier tube(PMT) introduces bias into the Na density results that are retrieved from the backscattered signals of Na resonance fluorescence lidar systems. The response characteristics of a PMT when stimulated by a series of light pulses with a fixed width of 1 μs are therefore used to develop a precise SIN model to estimate the relative error caused by SIN. Unless the strong signals that are returned from the lower atmosphere are excluded, the measured density results are always smaller than the actual values, and the resulting relative error may be 50% or more. Three potential solutions to reduce the SIN were quantified for comparison, including use of a chopper system, use of a gated circuit, and separation of the laser beam and the telescope receiver. When optimized parameters are used for these technologies, the relative error can then be reduced to less than 2%.

关键词： Lidar Signal-induced noise Photomultiplier tube

Rate of strong consistency of the maximum quasi-likelihood estimator in quasi-likelihood nonlinear models

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Applied Mathematics(A Journal of Chinese Universities) 2008年第4期23卷 391-400页

作者： XIA Tian kong fan-chao Dept. of Statist. Yunnan Univ. Kunming 650091 China Dept. of Math. Anhui Univ Hefei 230039 China

Quasi-likelihood nonlinear models （QLNM） include generalized linear models as a special case. Under some regularity conditions, the rate of the strong consistency of the maximum quasi-likelihood estimation （MQLE） is obtained in QLNM. In an important case, this rate is O（n-^1/2（loglogn）^1/2）, which is just the rate of LIL of partial sums for i.i.d variables, and thus cannot be improved anymore.

关键词： maximum quasi-likelihood estimator quasi-likelihood nonlinear models strong consistency

Large Deviation Results for Generalized Compound Negative Binomial Risk Models

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Acta Mathematicae Applicatae Sinica 2009年第1期25卷 151-158页

作者： fan-chao kong Chen Shen School of Mathematics Anhui University and Hefei Teachers College Hefei 230001 China

In this paper we extend and improve some results of the large deviation for random sums of random variables. Let {Xn;n 〉 1} be a sequence of non-negative, independent and identically distributed random variables with common heavy-tailed distribution function F and finite mean μ ∈R^＋, {N（n）; n ≥0} be a sequence of negative binomial distributed random variables with a parameter p C （0, 1）, n ≥ 0, let {M（n）; n ≥ 0} be a Poisson process with intensity λ 〉 0. Suppose {N（n）; n ≥ 0}, {Xn; n≥1} and {M（n）; n ≥ 0} are mutually independent. Write S（n） =N（n）∑i=1 Xi-cM（n）.Under the assumption F ∈ C, we prove some large deviation results. These results can be applied to certain problems in insurance and finance.

关键词： Poisson process negative binomial sequence large deviation heavy-tailed distribution ruinprobabili

Electrochemical deposition of Li_(2)S_(2)/Li_(2)S in aprotic Li–S batteries

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Particuology 2024年第7期90卷 516-521页

作者： Zhifeng Yao Xiaozhong fan Long kong School of Civil Engineering Xi'an University of Architecture&TechnologyXi'an 710055China Institute of Flexible Electronics(IFE) Northwestern Polytechnical UniversityXi'an 710129China

Lithium–sulfur(Li–S)batteries stand out the energy storage systems because of extremely high energy density(2600 W h Kg−1)and low-cost sulfur ***,the sluggish deposition from liquid Li polysulfides(LiPSs)to solid Li2S leads to mild power density and short cycle *** and regulating Li_(2)S_(2)/Li2S deposition are conceived to be importance to deliver second-plateau capacity in acceptable kinetics,which has the potential to operation Li–S batteries under electrolyte-lean *** perspective aims to summarize the proposed models that can describe the nucleation and propagation of three-dimensional Li_(2)S_(2)/Li2S,as well as affords critical views how electrolyte dictates LiPS conversion from liquid to *** hopes to encourage necessary scaffold strategies and electrolyte formulations to further improve energy density and life span of Li–S batteries.

关键词： Lithium–sulfur batteries Electrolyte Li_(2)S precipitation Characterization

Unadulterated carbon as robust multifunctional electrocatalyst for overall water splitting and oxygen transformation

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Nano Research 2020年第2期13卷 401-411页

作者： fantao kong Yu Qiao Chaoqi Zhang Xiaohong fan Aiguo kong Yongkui Shan School of Chemistry and Molecular Engineering East China Normal UniversityShanghai 200241China

Developing the highly efficient and durable non-precious metal electrocatalysts by taking advantage of inexpensive and abundant resources is of paramount importance for the widespread application of energy conversion and storage techniques such as fuel cells and metal-air ***,the sponge-like unadulterated carbontube-graphene complexes(D/G-CTs-1,000)with multifarious intrinsic defect active sites are fabricated by boric acid-hydrothermal and pyrolysis *** close contact or juncture between open nanotubes and few-layer graphene in D/G-CTs-1,000 constructs the hierarchical networks with plentifuchannels,the larger surface area and outstanding *** a result,the as-prepared D/G-CTs-1,000 electrocatalyst exhibits an excellent trifunctional electrocatalytic performance for oxygen reduction reaction(ORR),oxygen evolution reactior(OER)and hydrogen evolution reaction(HER).The primary Zn-air batteries and overall water splitting system using D/G-CTs-1,000 as the electrode materials delivers higher power density outperforming the advanced Pt/C-based batteries and the overall watersplitting performance comparable to those using the non-precious metal/carbon-based materials as *** work provides a universal and efficient synthetic strategy to produce the unadulterated carbons with high activity and long-time durability as trifunctional electrocatalysts and promote the widespread applications of metal-free electrocatalysts in sustainable energy conversior technology.

关键词： boric acid-splicing unadulterated carbon electrocatalysis rechargeable Zn-air battery overall water splitting

Admissibility for Linear Estimator of Parameter on Growth Curve Model with Respect to Linear Constraint

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Acta Mathematicae Applicatae Sinica 2009年第1期25卷 171-176页

作者： Ming-xiang Cao fan-chao kong Department of Mathematics Hefei Teachers College Heifei 230061 China Department of Mathematics Anhui University Hefei 230038 China

By using the vector-method of matrix, we study Growth Curve Model with respect to linear constraint. Under matrix loss function and vector loss function, we obtain necessary and sufficient conditions for admissibility... 详细信息

关键词： Growth curve model linear estimators admissibility

General Admissibility for Linear Estimators in a General Multivariate Linear Model under Balanced Loss Function

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Acta Mathematica Sinica,English Series 2013年第9期29卷 1823-1832页

作者： Ming Xiang CAO fan Chao kong Department of Mathematics Hefei Normal University School of Mathematics Anhui University

A generalization of Zellner’s balanced loss function is proposed. General admissibility in a general multivariate linear model is investigated under the generalized balanced loss function. And the sufficient and necessary conditions for linear estimators to be generally admissible in classes of homogeneous and nonhomogeneous linear estimators are given, respectively.

关键词： Balanced loss function linear estimators general optimality general admissibility

Enhanced wetting and properties of carbon/carbon-Cu composites with Cr_3C_2 coatings by Cr-solution immersion method

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Journal of Materials Science & Technology 2018年第3期34卷 458-465页

作者： Bo kong Jinming Ru Hongdi Zhang Tongxiang fan State Key Laboratory for Metal Matrix Composite Shanghai Jiaotong University Institute of Advanced Manufacturing and Modern Equipment Technology Jiangsu University

A facile ammonium-dichromate solution immersion method was introduced to synthesize the copperwettable Cr3C2 coating on and inside the carbon-carbon （C/C） preform. The formation mechanism and the microstructures of the Cr3C2 coatings were studied. The contact angle between molten copper and the C/C decreased from 140°to 60°, demonstrating the significant improvement in the wettability. The Cr3C2- coated C/C-Cu composite with only 4.2% porosity and 3.69 gcm^-3 density was manufactured through copper infiltration. As a result, the thermal and electrical conductivity of the modified C/C-Cu increased significantly due to the infiltrated copper. Also the mechanical properties of the composites including both the flexural and compressive strengths were enhanced by over 100%. The modified C/C-Cu composite exhibited lower friction coefficients and wear rates for different load levels than those of the commercial C/Cu composite. These results demonstrate the potential of the modified C/C-Cu material for use in electrical contacts.

关键词： Enhanced wetting and properties of carbon/carbon-Cu composites with Cr3C2 coatings by Cr-solution immersion method Cr Cu

Magnetically recyclable copper modified GO/Fe_3O_4 catalyst for efficient synthesis of quinazolinones

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Chinese Chemical Letters 2016年第6期27卷 827-831页

作者： Lu-Lu kong Li-Yan fan Department of Chemistry Tongji University

A series of bioactive quinazolinones were effectively synthesized by the condensation of halide benzamide with amino acid using magnetically recyclable GO/Fe3O4–CuI as catalyst. Magnetic GO/Fe3O4–CuI was prepared via a simple chemical method and characterized by FTIR, powder XRD, and *** heterogeneous copper catalyst can be easily separated from reaction mixtures by an external permanent magnet and reused without any obvious loss in activity which shows its applicability as a reusable and promising catalyst for quinazolinones synthesis.

关键词： Quinazolinones GO/Fe3O4–CuI Magnetically Recyclable Heterogeneous