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Interfacial mechanisms of heterogeneous Fenton reactions catalyzed by iron-based materials： A review

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Journal of Environmental Sciences 2016年第1期28卷 97-109页

作者： Jie He xiaofang Yang Bin Men Dongsheng Wang State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China University of Chinese Academy of Sciences Beijing 100049 China

The heterogeneous Fenton reaction can generate highly reactive hydroxyl radicals（·OH）from reactions between recyclable solid catalysts and H2O2 at acidic or even circumneutral ***,it can effectively oxidize refractory organics in water or soils and has become a promising environmentally friendly treatment *** to the complex reaction system,the mechanism behind heterogeneous Fenton reactions remains unresolved but fascinating,and is crucial for understanding Fenton chemistry and the development and application of efficient heterogeneous Fenton ***-based materials usually possess high catalytic activity,low cost,negligible toxicity and easy recovery,and are a superior type of heterogeneous Fenton ***,this article reviews the fundamental but important interfacial mechanisms of heterogeneous Fenton reactions catalyzed by iron-based materials..OH,hydroperoxyl radicals/superoxide anions（HO2./O2^-.）and high-valent iron are the three main types of reactive oxygen species（ROS）,with different oxidation reactivity and *** on the mechanisms of ROS generation,the interfacial mechanisms of heterogeneous Fenton systems can be classified as the homogeneous Fenton mechanism induced by surface-leached iron,the heterogeneous catalysis mechanism,and the heterogeneous reaction-induced homogeneous *** heterogeneous Fenton systems catalyzed by characteristic iron-based materials are comprehensively ***,related future research directions are also suggested.

关键词： Heterogeneous Fenton reactions ROS interfacial mechanisms iron-based materials

Chaotic Motion Analysis for a Coupled Magnetic-Flow-Mechanical Model of the Rectangular Conductive Thin Plate

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Computer Modeling in Engineering & Sciences 2023年第11期137卷 1749-1771页

作者： Xinzong Wang xiaofang Kang Qingguan Lei School of Civil Engineering Anhui Jianzhu UniversityHefei230601China Key Laboratory of Intelligent Underground Detection Technology Anhui Jianzhu UniversityHefei230601China

The chaotic motion behavior of the rectangular conductive thin plate that is simply supported on four sides by airflow andmechanical external excitation in a magnetic field is *** to Kirchhoff’s thin plate theory,considering geometric nonlinearity and using the principle of virtualwork,the nonlinearmotion partial differential equation of the rectangular conductive thin plate is *** the separate variable method and Galerkin’s method,the system motion partial differential equation is converted into the general equation of the Duffing equation;the Hamilton system is introduced,and the Melnikov function is used to analyze the Hamilton system,and obtain the critical surface for the existence of *** bifurcation diagram,phase portrait,time history response and Poincarémap of the vibration system are obtained by numerical simulation,and the correctness is *** results showthatwhen the ratio of external excitation amplitude to damping coefficient is higher than the critical surface,the system will enter chaotic *** chaotic motion of the rectangular conductive thin plate is affected by different magnetic field distributions and airflow.

关键词： Rectangular conductive thin plate chaotic airflow magnetic field Melnikov function Galerkin’s method

新时代党的创新理论传播的系统矩阵——以传播学五大范畴为视点

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河北大学学报（哲学社会科学版） 2025年第1期50卷 99-109页

作者：尤文梦山东大学马克思主义学院山东济南250100

习近平新时代中国特色社会主义思想内涵丰富、思想宏阔、逻辑严密,对丰富发展马克思主义作出了一系列原创性贡献,想要转化为推动中国式现代化的磅礴力量,传播最为关键。从社会传播范畴出发,推动新时代党的创新理论传播要着力架构涵盖人... 详细信息

习近平新时代中国特色社会主义思想内涵丰富、思想宏阔、逻辑严密,对丰富发展马克思主义作出了一系列原创性贡献,想要转化为推动中国式现代化的磅礴力量,传播最为关键。从社会传播范畴出发,推动新时代党的创新理论传播要着力架构涵盖人内传播、人际传播、群体传播、组织传播和大众传播在内的“五位一体”的多层次、立体化传播矩阵,积极寻求新时代党的创新理论与大众思想文化的共通意义空间,使理论传播体现时代性、把握规律性、富于创造性,才能以理论的深度、视野的宽度、语言的温度及传播的力度巩固壮大主流思想舆论,让新时代党的创新理论成为时代最强音,用“中国理论”凝聚“中国力量”。

关键词：党的创新理论传播习近平新时代中国特色社会主义思想

Reasoning and predicting POMDP planning complexity via covering numbers

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Frontiers of Computer Science 2016年第4期10卷 726-740页

作者： Zongzhang ZHANG Qiming FU xiaofang ZHANG Quan LIU School of Computer Science and Technology Soochow University Suzhou 215000 China Collaborative Innovation Center of Novel Software Technology and Industrialization Nanjing 210000 China School of Electronic and Information Engineering Suzhou University of Science and Technology Suzhou 215000 China Key Laboratory of Symbolic Computation and Knowledge Engineering of Ministry of Education Jilin University Changchun 130012 China

Partially observable Markov decision processes （POMDPs） provide a rich mathematical framework for planning tasks in partially observable stochastic environments. The notion of the covering number, a metric of capturing the search space size of a POMDP planning problem, has been proposed as a complexity measure of approximate POMDP planning. Existing theoretical results are based on POMDPs with finite and discrete state spaces and measured in the l1- metric space. When considering heuristics, they are assumed to be always admissible. This paper extends the theoretical results on the covering numbers of different search spaces, including the newly defined space reachable under inadmissible heuristics, to the ln-metric spaces. We provide a simple but scalable algorithm for estimating covering numbers. Experimentally, we provide estimated covering numbers of the search spaces reachable by following different policies on several benchmark problems, and analyze their abilities to predict the runtime of POMDP planning algorithms.

关键词： POMDP planning complexity theory covering number search space

Degradation kinetics and mechanism of aniline by heat-assisted persulfate oxidation

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Journal of Environmental Sciences 2012年第5期24卷 821-826页

作者： xiaofang Xie Yongqing Zhang Weilin Huang Shaobing Huang College of Environmental Science and Engineering and the Key Laboratory of Pollution Control and Ecosystem Restoration in Industry Clusters Ministry of Education South China University of Technology Guangzhou 510006 China Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology Guangzhou 510275 China Department of Environmental Sciences Rutgers The State University of New Jersey New Brunswick NJ 08901 USA

Oxidation of aniline by persulfate in aqueous solutions was investigated and the reaction kinetic rates under different temperature, persulfate concentration and pH conditions were examined in batch experiments. The results showed that, the aniline degradation followed pseudo first-order reaction model. Aniline degradation rate increased with increasing temperature or persulfate concentration. In the pH range of 3 to 11, a low aniline degradation rate was obtained at strong acid system （pH 3）, while a high degradation rate was achieved at strong alkalinity （pH 11）. Maximum aniline degradation occurred at pH 7 when the solution was in a weak level of acid and alkalinity （pH 5, 7 and 9）. Produced intermediates during the oxidation process were identified using liquid chromatography-mass spectrometry technology. And nitrobenzene, 4-4’-diaminodiphenyl and 1-hydroxy-1,2-diphenylhydrazine have been identified as the major intermediates of aniline oxidation by persulfate and the degradation mechanism of aniline was also tentatively proposed.

关键词： persulfate oxidation kinetic mechanism aniline

Mixed mode oscillations as well as the bifurcation mechanism in a Duffing’s oscillator with two external periodic excitations

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Science China(Technological Sciences) 2019年第10期62卷 1816-1824页

作者： ZHANG xiaofang ZHENG JianKang WU GuoQing BI QinSheng Faculty of Civil Engineering and Mechanics Jiangsu UniversityZhenjiang212013China School of Mechanical Engineering Nantong Institute of TechnologyNantong226002China

The main purpose of the paper is to present an approach to account for the mechanism of bursting oscillations occurring in the systems with multiple periodic excitations. Since the traditional slow-fast analysis method can be used only for the systems with two scales in time domain, when there exists an order gap between the exciting frequencies and the natural frequency, how to explore the mechanism of the complicated dynamics remains an open problem, especially for the case when two exciting terms exist. To explain our approach, a relative simple Duffing’s oscillator with two external periodic excitations is introduced as an example. For the case when one exciting frequency is integer times of the other exciting frequency, by employing Moivre’s equation, the two exciting terms can be transformed into the functions of one basic periodic exciting term. Regarding the basic periodic exciting term as a slow-varying parameter, the two exciting terms can be changed into the functions of the slow-varying parameter, based on which the whole model can be transformed into a generalized autonomous system with one slow-varying parameter. Equilibrium branches as well as the related bifurcations of the generalized autonomous system can be derived with the variations of the amplitudes of the two excitations, which describes the relationship between the state variables of the generalized autonomous system and the slow-varying parameter. Considering the slow-varying parameter as a generalized state variable, one may obtain the so-called transformed phase portraits, which present the relationship between the state variable and the slowvarying parameter. The bifurcation mechanism of the mixed oscillations can be obtained by overlapping the equilibrium branches and the transformed phase portraits. Upon the approach, different types of bursting oscillations are presented. It is pointed that when the trajectory moves almost strictly along the segments of the stable equilibrium branches

关键词： multiple external periodic excitations two scales in frequency domain bursting oscillations bifurcation mechanism

Microstructure and Magnetic Anisotropy of FeCoNbB Films

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Chinese Journal of Aeronautics 2011年第6期24卷 823-828页

作者： YANG youran WANG Yanyan LI Ying BI xiaofang Key Laboratory of Aerospace Materials and Performance （Ministry of Education） School of Materials Science and Engineering Beihang University Beijing 100191 China

Effect of Nb contents on microstructure and magnetic properties of FeCoNbB films has been studied. X-ray diffraction （XRD） analysis reveals that Nb plays a role in refining grain and in facilitating formation of amorphous structure. When Nb content is more than 8 at%, the films transform from crystalline to amorphous structure, accompanied by variations in magnetic properties. An unusual out-of-plane anisotropy component is consequently observed. It can be suggested that the anisotropy induced by increasing Nb contents be attributed to stress-related magnetoelastic anisotropy. The undesirable anisotropy is greatly reduced by thermal annealing, reducing film thicknesses or applying an external magnetic field together with Si addition.

关键词： FeCoNbB films magnetic anisotropy Nb contents annealing film thickness

Variable strength combinatorial testing of concurrent programs

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Frontiers of Computer Science 2016年第4期10卷 631-643页

作者： xiaofang QI Jun HE Peng WANG Huayang ZHOU School of Computer Science and Engineering Southeast University Nanjing 211189 China Key Laboratory of Computer Network and Information Integration Ministry of Education Southeast University Nanjing 211189 China NARI Relays Electric Cooperation Nanjing 211102 China

Reachability testing is an important approach to testing concurrent programs. It generates and exercises syn- chronization sequences automatically and on-the-fly without saving any test history. Existing reach, ability testing can be classified into exhaustive and t-way testing. Exhaustive testing is impractical in many cases whilie t-way testing may decrease the capability of fault detection in some cases. In this paper, we present a variable strengda reachability testing strategy, which adopts the dynamic framework of reachability testing and uses a variable strength combinatorial strategy. Different parameter groups are provided with different covering strength. Variable strength testing covers no t-way combinations but the necessary combinations of parameters having mutual interactions in a concurrent program. It is more reasonable than t-way testing because uniform interactions between parameters do not often exist in concurrent systems. We propose a merging algorithm that implements the variable strength combinatorial testing strategy and conduct our experiment on several concurrent programs. The experimental results indicate that our variable strength reachability testing reaches a good tradeoff between the effectiveness and efficiency. It can keep the same capability of fault detection as exhaustive reachability testing while substantially reducing the number of synchronization sequences and decreasing the execution time in most cases.

关键词： software testing variable strength combinatorial testing concurrency testing reachability testing

Preparation and Characterization of Single-Phase Perovskite La_(0.6)Sr_(0.4)Co_(0.8)Fe_(0.2)O_(3-δ)

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Journal of Natural Gas Chemistry 2006年第1期15卷 58-62页

作者： Wenhui Yuan xiaofang Hu Li Li College of Chemical Engineering and Energy South China University of Technology Guangdong Key Laboratory of Green Chemicals Guangzhou 510640 China

Single-phase perovskite La0.6Sr0.4Co0.8Fe0.2O3-δ has been successfully prepared by using citrate-EDTA complexation method at relatively low calcination temperature. The structure and thermal decomposition process of the complex precursor have been investigated by means of differential scanning calorimetry-thermal gravimetric analysis （DSC/TGA）, X-ray diffraction （XRD）, and Fourier transform infrared spectroscopic （FT-IR） measurements. The precursor decomposed completely and started to form perovskite-type oxide above 420 ℃ according to the differential scanning calorimetry （DSC） and thermal gravimetric analysis （TGA） results. Single-phase perovskite La0.6Sr0.4Co0.8Fe0.2O3-δ obtained has been confirmed from the XRD pattern, and no peak of SrCO3 was found by XRD of the oxides synthesized at a relatively low temperature of 800℃. The reducibility of La0.6Sr0.4Co0.8Fe0.2O3-δ was also characterized by the temperature programmed reduction （TPR） technique. Disk shaped dense La0.6Sr0.4Co0.8Fe0.2O3-δ membrane was prepared by the isostatical pressing method. The oxygen flux rate of dense La0.6Sr0.4Co0.8Fe0.2O3-δ membrane was （2.8-18）× 10^-8 mol/（cm^2.s） in the temperature range of 800-1000 ℃.

关键词： perovskite La0.6Sr0.4Co0.8Fe0.2O3-δ oxygen permeation preparation characterization