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Application of Backward Nonlinear Local Lyapunov Exponent Method to Assessing the Relative Impacts of Initial Condition and Model Errors on Local Backward Predictability

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Advances in Atmospheric Sciences 2021年第9期38卷 1486-1496页

作者： Xuan li Jie FENG Ruiqiang DING Jianping li Department of Atmospheric and Oceanic Sciences and Institute of Atmospheric Sciences Fudan UniversityShanghai 200438China State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing 100875China Frontiers Science Center for Deep Ocean Multispheres and Earth System(FDOMES)/Key Laboratory of Physical Oceanography/Institute for Advanced Ocean Studies Ocean University of ChinaQingdao 266100China Laboratory for Ocean Dynamics and Climate Pilot Qingdao National Laboratory for Marine Science and Technology(QNLM)Qingdao 266237China

Initial condition and model errors both contribute to the loss of atmospheric ***,it remains debatable which type of error has the larger impact on the prediction lead time of specific *** this study,we perform a theoretical study to investigate the relative effects of initial condition and model errors on local prediction lead time of given states in the Lorenz *** the backward nonlinear local Lyapunov exponent method,the prediction lead time,also called local backward predictability limit(LBPL),of given states induced by the two types of errors can be quantitatively *** show that the structure of the Lorenz attractor leads to a layered distribution of LBPLs of *** an individual circular orbit,the LBPLs are roughly the same,whereas they are different on different *** spatial distributions of LBPLs show that the relative effects of initial condition and model errors on local backward predictability depend on the locations of given states on the dynamical trajectory and the error *** the error magnitude is fixed,the differences between the LBPLs vary with the locations of given *** larger differences are mainly located on the inner trajectories of *** the error magnitudes are different,the dissimilarities in LBPLs are diverse for the same given state.

关键词： Initial condition model errors error magnitude error location LBPL

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Appraisal of coastal recreational resources in Qingdao by travel cost method

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Frontiers of Environmental Science & Engineering 2009年第3期3卷 341-347页

作者： Jingmei li Tieying liU Yuanyuan ZHANG Lei li School of Economics Ocean University of ChinaQingdao 266071China

This paper serves to appraise the monetary cost of coastal recreational resources in Qingdao using the travel cost method(TCM),which is typically used in developed *** total revenue produced by Qingdao’s coastal recreational resources is about RMB 5.511010 annually,based on questionnaires given at Qingdao’s major tourist *** questionnaires establish correlation functions that factor in the number of tourists,travel expenses,*** data processing software named Eviews was used to determine the tourist demand regression curve and to calculate their residual and actual travel *** results of this study can provide a scientific basis for applicable industries interested in development and management ***,this study assesses the reasonable usage of coastal recreational resources.

关键词： coastal recreational resources travel cost method(TCM) regression analysis Qingdao China

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Modified Cascade Synchronization Scheme for Discrete-Time Hyperchaotic Systems

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Communications in Theoretical Physics 2008年第10期50卷 919-924页

作者： ZHU Hai-Xing li Yong-Zhi AN Hong-li Department of Mathematics Southeast University Nanjing 210096 China Department of Computer Science and Engineering Nanjing Forestry University Nanjing 210037 China Nonlinear Science Center and Department of Mathematics Ningbo University Ningbo 315211 China

In this paper, the modified cascade synchronization scheme is proposed to investigate the synchronization in discrete-time hyperchaotic systems. By choosing a general kind of proportional scaling error functions and based on rigorous control theory, we take the discrete-time hyperchaotic system due to Wang and 3D generalized Henon map as two examples to achieve the modified cascade synchronization, respectively. Numerical simulations are used to verify the effectiveness of the proposed technique.

关键词： chaos synchronization discrete-time hyperchaotic systems modified cascade synchronization

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Synthesis of Mesoporous （Ga1-xZnx）（N1-xOx） Using Layered Double Hydroxides as Precursors for Enhanced Visible-light Driven H2 Production

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Chinese Journal of Chemistry 2017年第2期35卷 196-202页

作者： li, Xuedong Zhang, Qinghong Wang, Hongzhi li, Yaogang Donghua Univ Coll Mat Sci & Engn State Key Lab Modificat Chem Fibers & Polymer Mat Shanghai 201620 Peoples R China Donghua Univ Engn Res Ctr Adv Glasses Mfg Technol Shanghai 201620 Peoples R China

Mesoporous （Ga1-xZnx）（N1-xOx） hexagonal nanoplates were prepared by nitridation of layered double hydrox- ides （LDHs） containing Zn2＋ and Ga3＋ ions with different [Zn]/[Ga] ratios. Their specific surface areas ranged from 21.25 to 50.95 m2/g were much higher than those previously reported. The （Ga1-xZnx）（N1-xOx） showed broad visible light absorption and reduced band gaps with increasing Zn content. When [Zn]/[Ga]=2, the （Ga1-xZnx）（N1-xOx） absorbed strongly the light of wavelength less than 525 nm and showed the highest visible light driven 142 production efficiency. After totally repeated runs for 30 h, the H2-production activity of （Ga1-xZnx）（N1-xOx） did not fall off, indicating its good photochemical stability and photocatalytic activity for long time. Herein, the results pro- vide new insights into （Ga1-xZnx）（N1-xOx） as high performance photocatalyst and their potential application in visi- ble-light driven water splitting H2 production.

关键词： (Ga1-xZnx)(N1-xOx) photocatalyst visible light H2 production

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Assessment of temporal and spatial variations in water quality using multivariate statistical methods： a case study of the Xin＇anjiang River, China

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Frontiers of Environmental Science & Engineering 2014年第6期8卷 895-904页

作者： Xue li Pengjing li Dong WANG Yuqiu WANG College of Environmental Science and Engineering Nankai University Tianjin 300071 China Chinese Academy for Environmental Planning Water Environment Institute Beijing 100012 China

This study evaluated the temporal and spatial variations of water quality data sets for the Xin＇anjiang River through the use of multivariate statistical techniques, including cluster analysis （CA）, discriminant analysis （DA）, correlation analysis, and principal component analysis （PCA）. The water samples, measured by ten parameters, were collected every month for three years （2008-2010） from eight sampling stations located along the river. The hierarchical CA classified the 12 months into three periods （First, Second and Third Period） and the eight sampling sites into three groups （Groups 1, 2 and 3） based on seasonal differences and various pollution levels caused by physicochemical properties and anthropogenic activ- ities. DA identified three significant parameters （tempera- ture, pH and ***） to distinguish temporal groups with close to 76% correct assignment. The DA also discovered five parameters （temperature, electricity conductivity, total nitrogen, chemical oxygen demand and total phosphorus） for spatial variation analysis, with 80.56% correct assignment. The non-parametric correlation coefficient （Spear- man R） explained the relationship between the water quality parameters and the basin characteristics, and the GIS made the results visual and direct. The PCA identified four PCs for Groups 1 and 2, and three PCs for Group 3. These PCs captured 68.94%, 67.48% and 70.35% of the total variance of Groups 1, 2 and 3, respectively. Although natural pollution affects the Xin＇anjiang River, the main sources of pollution included agricultural activities, industrial waste, and domestic wastewater.

关键词： Xin'anjiang River multivariable statistical analysis temporal variation spatial variation water quality

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A numerical study on the effect of tidal flat's slope on tidal dynamics in the Xiangshan Bay, China

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Acta Oceanologica Sinica 2018年第9期37卷 29-40页

作者： li li YE Taoyan HE Zhiguo XIA Yuezhang Ocean College Zhejiang University State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of OceanographyState Oceanic Administration

The Xiangshan Bay is a semi-enclosed and narrow bay, which is characterized by large scale tidal flats and has been historically utilized through coastal construction and aquaculture engineering. The hydrodynamic model using the Finite Volume Coastal Ocean Model（FVCOM） was constructed to examine the changes of tidal dynamics due to the variation of tidal flat slopes. According to the model results, a decreased slope of a tidal flat would amplify the M2 tidal amplitude and delay the M2 tidal phase in the inner harbor, due to an increased tidal prism, and vice versa. The amplitude of the main shallow-water tide M4 would be amplified/dampened in the entire bay due to the changed bottom friction, if the tidal flat＇s slope were reduced/increased at the Tie inlet. The phase was advanced. The change of a tidal flat＇s slope at the Tie inlet had greater impacts on tidal amplitude,phase and duration asymmetry, than that at the Xihu inlet. The impact of changes of the tidal flat slope at the Xihu inlet was small and was constrained locally. Changes in the tidal flats＇ slopes at the Tie and Xihu inlets changed the tidal duration asymmetry, residual current and tidal energy via modulating tides. The ebb dominance decreased when the tidal flat＇s slope at the Tie inlet was changed. Decreased/increased ebb dominance occurred when the tidal flat＇s slope was reduced/increased at the Xihu inlet. The residual current and tidal energy density was amplified/dampened and more/less tidal energy was dissipated, with reduced/increased slope at both of the inlets. The findings in this study are instructive to coastal engineering and estuarine management.

关键词： tidal flat's slope tidal dynamics tidal asymmetry tidal energy Xiangshan Bay

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Immobilization of PANI on Mesoporous Carbon： Preparation and Supercapacitor Performance

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Transactions of Nanjing University of Aeronautics and Astronautics 2018年第4期35卷 630-638页

作者： li Jinjin liu Yang li Kunyang Bao Shujuan Urban Vocational College of Sichuan Chengdu 610101 P.R. China Institute for Clean Energy & Advanced Materials Faculty of Materials and Energy Southwest UniversityChongqing 400715 P.R. China

Polyaniline(PANI)was effectively immobilized on the surface of ordered mesoporous carbon(OMC)by using Mn_2O_3 as sacrificial *** observed microstructure and morphology indicate that a thin layer of PANI was coated on OMC *** a supercapacitor electrode material,the discharge capacity of the optimized PANI/OMC could reach 467 F/g,which is far higher than that of OMC,PANI and Mn_2O_3/***,PANI/OMC composites with different content of PANI are obtained by adjusting the amount of Mn_2O_3 on OMC and their properties are *** results show that a thin layer of PANI can improve the capacity of PANI/OMC composites effectively and the further increase of PANI reduces the capacity of PANI/OMC *** sacrificial template method presented here is beneficial to coating a layer of polymer on carbon materials,and the content of polymer layer can be controlled by adjusting the amount of Mn_2O_3 in Mn_2O_3/OMC.

关键词： Mn2O3 sacrificial template polyaniline(PANI) supercapacitor

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Embrittlement and toughening in CGHAZ of ASTM4130 steel

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Science China(Physics,Mechanics & Astronomy) 2011年第8期54卷 1447-1454页

作者： li liYing WANG Yong HAN Tao li ChaoWen College of Mechanical and Electronic Engineering China University of Petroleum Dongying 257061 China

In the present investigation, a thermal welding simulation technique was used to investigate the mechanical properties and microstructure features of the coarse-grained heat-affected zone (CGHAZ) of ASTM4130 steel. The effect of post welding heat treatment (PWHT) and welding heat inputs on the toughness of CGHAZ was also analyzed. The results show that CGHAZ has the lowest toughness, which is only 5.5%-7.1% of the base metal. CGHAZ is mainly composed of dislocation martensite, up-per and lower bainite, and M-A constituents. But after PWHT, carbides precipitate from non-equilibrium microstructures of CGHAZ accompanying some retained austenite which transforms into low bainite, thereby enhancing toughness over the base metal. Therefore, the key microstructure factors affecting fracture toughness are lathlike non-equilibrium microstructure and lowered supersaturation before and after PWHT respectively. When welding heat input is between 12 kJ/cm and 28 kJ/cm, the mechanical properties in CGHAZ of ASTM4130 with single-pass welding can satisfy the requirements when PWHT is applied.

关键词： ASTM4130 steel coarse-grained heat-affected zone embrittlement toughening

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Molecular and functional characterization of three novel carboxylesterases in the detoxification of permethrin in the mosquito, Culex quinquefasciatus

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Insect Science 2022年第1期29卷 199-214页

作者： Youhui Gong Ming li Ting li Nannan liu Department of Entomology and Plant Pathology Auburn UniversityAuburnAlabamaUSA State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijingChina Department of Biology Sciences University of CaliforniaSan DiegoCaliforniaUSA

Carboxylesterases (CarEs) belong to a super family of multifunctional enzymes associated with the degradation of endogenous and exogenous compounds. Many insect CarEs are known to play important roles in catalyzing the hydrolysis of organophosphates (OPs), carbamates, and synthetic pyrethroids (SPs). The elevation of esterase activity through gene amplification and overexpression of estα2 and estβ2 genes contributes to the development of resistance to OP insecticides in the mosquito Culex quinquefasciatus. Three additional CarE genes are upregulated in permethrin-resistant Cx. quinquefasciatus according to an RNA-seq analysis, but their function remains unknown. In this study, we, for the first time, characterized the function of these three novel genes using in vitro protein expression, an insecticide metabolism study and molecular docking analysis. All three CarE genes were significantly overexpressed in resistant mosquito larvae, but not adults, compared to susceptible strain. No gene copy differences in these three genes were found in the mosquitoes tested. In vitro high-performance liquid chromatography (HPLC) revealed that CPIJ018231, CPIJ018232, and CPIJ018233 metabolized 30.4% ± 2.9%, 34.7% ± 6.8%, and 23.2% ± 2.2% of the permethrin, respectively. No mutations in resistant strains might significantly affect their CarE hydrolysis ability. A docking analysis further confirmed that these three CarEs from resistant strain all potentially metabolize permethrin. Taken together, these three carboxylesterase genes could play important roles in the development of permethrin resistance in Cx. quinquefasciatus larvae through transcriptional overexpression, metabolism, and detoxification.

关键词： carboxylesterase Culex quinquefasciatus gene expression in vitro protein expression metabolism permethrin resistance

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Calculation model of military aircraft suryiyability to a missile

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High Technology Letters 2014年第2期20卷 117-123页

作者：杨哲 li Shulin li Shouan Zhou li Zhang Jun The Engineering Institute Air Force Engineering University Aviation University of Air Force Air Force Equipment Research Academy

Since missiles are main threat against aircrafts in air war,a model is proposed for calculating the aircraft survivability to a *** hit characteristic of aircraft to a missile is analyzed,and then Monte Carlo method is applied to generate missile detonation location according to its distribution *** addition,based on the analysis of fragment trajectory and critical components,the intersection point of these two is *** the kill probability of critical component to a fragment can be calculated,and the aircraft survivability to a missile is obtained ***,the feasibility of the proposed method is *** results show that this method captures the basic effects of missile detonation locations on aircraft survivability,which may provide an effective reference to aircraft survivability research.

关键词： survivability missile miss distance Monte Carlo kill probability

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