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Identifying the dynamic behaviors in complete reconstruction of Co-based complex precatalysts during electrocatalytic oxygen evolution

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Journal of Energy Chemistry 2025年第1期100卷 226-233页

作者： Jingfang Zhang Danyang Wu Linke Cai Youluan Lu Fanpeng cheng Lijuan Shi qun Yi Yao Liu Yi Huang Key Laboratory of Green Chemical Engineering Process of Ministry of Education Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of Education Hubei Key Laboratory of Novel Reactor and Green Chemical Technology School of Chemical Engineering & Pharmacy Wuhan Institute of Technology Key Laboratory of Pesticide & Chemical Biology of Ministry of Education Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction of Ministry of Education College of Chemistry Central China Normal University College of Materials Science and Engineering Fuzhou University

Transition metal-based nanomaterials have emerged as promising electrocatalysts for oxygen evolution reaction（OER）. Considerable research efforts have shown that self-reconstruction occurs on these nanomaterials under operating conditions of OER process. However, most of them undergo incomplete reconstruction with limited thickness of reconstruction layer, leading to low component utilization and arduous exploration of real catalytic mechanism. Herein, we identify the dynamic behaviors in complete reconstruction of Co-based complexes during OER. The hollow phytic acid（PA） cross-linked CoFe-based complex nanoboxes with porous nanowalls are designed because of their good electrolyte penetration and mass transport ability, in favor of the fast and complete reconstruction. A series of experiment characterizations demonstrate that the reconstruction process includes the fast substitution of PA by OH-to form Co（Fe）(OH)xand subsequent potential-driven oxidation to Co（Fe）OOH. The obtained CoFeOOH delivers a low overpotential of 290 mV at a current density of 10 mA cm-2and a long-term *** experiment results together with theory calculations reveal that the Fe incorporation can result in the electron rearrangement of reconstructed CoFeOOH and optimization of their electronic structure,accounting for the enhanced OER activity. The work provides new insights into complete reconstruction of metal-based complexes during OER and offers guidelines for rational design of high-performance electrocatalysts.

关键词： Complete reconstruction Co-based complex Precatalysts Oxygen evolution reaction

A PARALLEL NONOVERLAPPING DOMAIN DECOMPOSITION METHOD FOR STOKES PROBLEMS

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Journal of Computational Mathematics 2006年第2期24卷 209-224页

作者： mei-qun Jiang Pei-liang Dai Department of Mathematics Suzhou university Suzhou 215006 China Department of Mathematics Changshu Institute of Technology Changshu 215500 China

A nonoverlapping domain decomposition iterative procedure is developed and analyzed for generalized Stokes problems and their finite element approximate problems in R^N（N=2,3）. The method is based on a mixed-type consistency condition with two parameters as a transmission condition together with a derivative-free transmission data updating technique on the artificial interfaces. The method can be applied to a general multi-subdomain decomposition and implemented on parallel machines with local simple communications naturally.

关键词： Generalized Stokes problem Nonoverlapping Domain decomposition Mixedfinite element Crouzeix-Raviart element.

Flexible High Energy Density Sodium Dual-ion Battery with Long Cycle life

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Energy & Environmental Materials 2022年第4期5卷 1285-1293页

作者： Yongpeng Li qun Guan Jianli cheng Bin Wang Institute of Chemical Materials China Academy of Engineering PhysicsMianyang 621900China Institute of Fundamental and Frontiers Sciences Yangtze Delta Region Institute(Huzhou)University of Electronic Sciences and Technology of ChinaChengdu 611731China

Flexible fiber-shaped sodium dual-ion batteries(FSDIBS)as a proof of concept are fabricated by using the hierarchical ReS_(2) nanosheets anchored on the carbon nanotube(ReS_(2)@CNT)fiber as anode and graphite on the CNT as *** to large interlayer spacing and weak layer coupling force of the ReS_(2) nanosheets and the anion accommodation of the graphite combined with good flexibility of the CNT fiber,the FSDIBS demonstrate outstanding electrochemical performances with high working voltage and high specific volumetric energy density,durable cycling life,and good *** FSDIBS show a specific discharge capacity of 97.8 mAh cm^(−3) at a current density of 630 mA cm^(−3) and high specific energy density of 25.12 mWh cm^(−3)(based on the whole volume of the two electrodes)and superb stability with a capacity retention of 91.8%even after bending for 2100 ***,a series of ex situ/in situ characterizations are verified that the reversible shuttles of the Na^(+) cations and PF_(6)^(-) anions between the anode and cathode are simultaneously occurred during the charge/discharge process.

关键词： dual-ion batteries fiber-shaped flexibility ReS_(2) sodium ions

Modified joint probabilistic data association with classification-aided for multitarget tracking

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Journal of Systems Engineering and Electronics 2008年第3期19卷 434-439页

作者： Ba Hongxin Cao Lei He Xinyi cheng qun Air Force Command Coll. Beijing 100097 P. R. China Inst. of Command Automation PLA Univ. of Science & Technology Nanjing 210007 P. R. China Inst. of Combat Systems Naval Academy of Armament Beijing 100073 P. R. China Scientific Research Dept. PLA Univ. of Science & Technology Nanjing 210007 P. R. China

Joint probabilistic data association is an effective method for tracking multiple targets in clutter, but only the target kinematic information is used in measure-to-track association. If the kinematic likelihoods are similar for different closely spaced targets, there is ambiguity in using the kinematic information alone; the correct association probability will decrease in conventional joint probabilistic data association algorithm and track coalescence will occur easily. A modified algorithm of joint probabilistic data association with classification-aided is presented, which avoids track coalescence when tracking multiple neighboring targets. Firstly, an identification matrix is defined, which is used to simplify validation matrix to decrease computational complexity. Then, target class information is integrated into the data association process. Performance comparisons with and without the use of class information in JPDA are presented on multiple closely spaced maneuvering targets tracking problem. Simulation results quantify the benefits of classification-aided JPDA for improved multiple targets tracking, especially in the presence of association uncertainty in the kinematic measurement and target maneuvering. Simulation results indicate that the algorithm is valid.

关键词： multi-target tracking data association joint probabilistic data association classification information,track coalescence maneuvering target.

Report on Childhood Obesity in China (7) Comparison of NCHS and WGOC

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Biomedical and Environmental Sciences 2008年第4期21卷 271-279页

作者： YI-qun XU cheng-YE JI 无 Institute of Child and Adolescent Health Peking University of Health Science Center Beijing 100083 China COOPERATIVE STUDY ON CHILDHOOD OBESITY： WORKING GROUP ON OBESITY IN CHINA

Objective To test the validity of Working Group on Obesity in China （WGOC） reference in screening childhood obesity using obesity-related metabolic syndrome （MS） and its components as disease risk evidence. Methods A total of 2020 adolescents （1007 boys and 1013 girls） aged 14-16 years were sampled in Beijing, China. Anthropometric and biochemical measurements, as well as blood pressure parameters were available. Prevalence of overweight/obesity and related MS risk factors were analyzed across different body mass index （BMI） categories. The sensitivity and specificity of the WGOC cut-offs were compared with those of National Central Health Statistics （NCHS）. Results Significantly high prevalence of MS and its components were found both in the obesity and overweight groups, which were classified by the WGOC and NCHS references. Similar distribution pattern of MS risk factors existed among different BMI categories, but the frequency and clustering of these factors in the obesity group classified by the NCHS were much higher. Owing to its irrelevant high cut-offs for overweight/obesity （especially for girls since the mid- adolescence）, the NCHS reference had a high specificity but a low sensitivity. By contrast, the WGOC reference with a high sensitivity （90.1% for boys and 89.2% for girls） and a relative high specificity （96.4% and 92.8% for obese boys and girls, 78.1% and 68.9% for overweight boys and girls respectively） was more suitable to support the need for early screening, intervention, and treatment of childhood obesity in China. Conclusion High sensitivity is more important than specificity in choosing appropriate screening tools for childhood obesity. Validity test demonstrates that it is rational to use the WGOC reference, established on the basis of the Chinese own reference population as a uniform screening tool for childhood obesity, which can effectively overcome the unnecessary treatment and psychosociai implications of stigmatization caused by misclas

关键词： Body mass index Childhood obesity Overweight Metabolic syndromes Validity

Adaptive Backstepping Sliding Mode Control of Uncertain Semi-Strict Nonlinear Systems and Application to Permanent Magnet Synchronous Motor

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Journal of Systems Science & Complexity 2021年第2期34卷 552-571页

作者： WANG Fang WANG Jian-mei WANG Kun ZONG qun HUA Changchun School of Science Yanshan UniversityQinhuangdao 066004China School of Electrical and Information Engineering Tianjin UniversityTianjin 300072China School of Electrical and Engineering Yanshan UniversityQinhuangdao 066004China

A disturbance observer(DOB)based-backstepping sliding mode control scheme is discussed for a class of semi-strict nonlinear system with unknown parameters and mismatched ***,adaptive technique and DOB are respectively applied to tackle the unknown parameters and mismatched uncertainty,where the DOB can effectively alleviate the chattering problem of sliding mode control(SMC).Then,exponential sliding mode surface is proposed to improve the convergence rate of the sliding mode ***‘explosion of complexity’problem inherent in conventional backstepping control is overcome by designing the novel first-order *** stability of the closed-loop system is analyzed in the framework of Lyapunov stability theory,in which the tracking error converges to an arbitrarily small neighborhood around zero(ASNZ).At last,two examples are given to illustrate the effectiveness of the proposed control strategy.

关键词： Adaptive law DOB filter semi-strict nonlinear system SMC

The novel usage of thiourea nitrate in aryl nitration

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Chinese Chemical Letters 2014年第1期25卷 87-89页

作者： Ge Meng mei-Lin Zheng A-qun Zheng mei Wang Juan Shi School of Pharmacy Xi’an Jiaotong University School of Science Xi’an Jiaotong University

Thiourea nitrate （TN） was easily prepared from thiourea and nitric acid to explore its use as a new nitration reagent, Nitrations of various aromatic compounds utilizing TN in concentrated sulfuric acid were studied, TN could convert aromatic compounds to the corresponding nitrated derivatives with various abnormal yields under mild conditions. The results suggested that the reaction mechanism might be different from those of traditional nitration reagents.

关键词： Thiourea nitrate Nitration Thiourea Aromatic compounds

A Rapid and Convenient Synthesis of Acylals from Aldehydes and Acetic Anhydrides Catalyzed by SnCl_4/SiO_2

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Chinese Chemical Letters 2001年第7期12卷 565-568页

作者： Yi qun LI Li Hui cheng Department of Chemistry Jinan UniversityGuangzhou 510632

A variety of aldehydes were converted into acylals in excellent yields with acetic anhydride in the presence of a catalytic amount of tin (IV) chloride supported on silica gel at room temperature.

关键词： Acylals tin (IV) chloride supported on silica gel

Constituent phases of the passive film formed on 2205 stainless steel by dynamic electrochemical impedance spectroscopy

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International Journal of Minerals,Metallurgy and Materials 2011年第1期18卷 42-47页

作者： Xue-qun cheng cheng-tao Li Chao-fang Dong Xiao-gang Li Corrosion and Protection Center University of Science and Technology Beijing Beijing 100083 China Key Laboratory of the Ministry of Education of China for Corrosion and Protection Beijing 100083 China

The passive film formed on 2205 duplex stainless steel（DSS） in 0.5 M NaHCO3＋0.5 M NaCl aqueous solution was characterized by electrochemical measurements,including potentiodynamic anodic polarization and dynamic electrochemical impedance spectroscopy（DEIS）.The results demonstrate that there is a great difference between the passive film evolutions of ferrite and *** impedance values of ferrite are higher than those of *** impedance peaks of ferritic and austenitic phases correspond to the potential of 0.15 and 0.25 V in the low potential range and correspond to 0.8 and 0.75 V in the high potential *** evolutions of the capacitance of both phases are reverse compared to the evolutions of *** thickness variations obtained from capacitance agree well with those of impedance *** results can be used to explain why pitting corrosion occurs more easily in austenite phase than in ferrite phase.

关键词： stainless steel electrochemical impedance spectroscopy ferrite austenite passivation films