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Fluorescence Turn-On/Off Responses of In(Ⅲ)-MOF to Short-Chain Perfluorocarboxylic Acids

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Transactions of Tianjin University 2023年第3期29卷 216-224页

作者： Jie Lv Yabo xie Lin-Hua Xie Jian-Rong Li Beijing Key Laboratory for Green Catalysis and Separation Department of Chemical EngineeringBeijing University of TechnologyBeijing 100124China

Short-chain perfluorocarboxylic acids(PFCAs) are a class of persistent organic pollutants that are widely used as substitutes for long-chain PFCAs. However, they also pose a non-negligible risk to ecosystems. In this study, we demonstrated that a fluorescent metal–organic framework(MOF)(named V-101) constructed from In^(3+)and an aromatic-rich tetratopic carboxylate ligand 5-[2,6-bis(4-carboxyphenyl) pyridin-4-yl] isophthalic acid(H4BCPIA) exhibited highly efficient turn-off and turn-on fluorescence responses toward five short-chain PFCAs in water and methanol, respectively. The limits of detection of V-101 toward five short-chain PFCAs are down to μg/L level, and it showed good anti-interference abilities toward short-chain PFCAs in the presence of common metal ions. The major mechanisms associated with fluorescence responses were molecular collisions and interactions between V-101 and short-chain PFCAs. This work demonstrates that the structure variety of MOFs imparts them with the potential of MOFs in the detection of short-chain PFCAs for pollution control.

关键词： Perfl uorocarboxylic acids Fluorescent detection Metal–organic framework(MOF)

High-speed train positioning based on a combination of Beidou navigation, inertial navigation and an electronic map

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Science China(Information Sciences) 2023年第7期66卷 237-252页

作者： Hui YANG Shuai-Qiang DONG Chun-Hua Xie School of Electrical and Automation Engineering East China Jiaotong University Key Laboratory of Advanced Control & Optimization of Jiangxi Province East China Jiaotong University State Key Laboratory of Performance Monitoring Protecting of Rail Transit Infrastructure East China Jiaotong University

To date, the studies on the combination positioning of high-speed trains have made great progress, but the positioning accuracy of these methods is relatively low. Map-matching positioning can improve positioning accuracy, but information transmission is time-consuming. Few studies incorporate it into combination positioning. To solve the problem, this paper proposes a high-speed train positioning method based on combining a Beidou navigation system, an inertial navigation system, and an electronic map. First, the combination positioning problem is transformed into a multi-objective optimization problem, which weights the direction similarity and distance error to form a fitness function and converts the railway line and the maximum error range of each positioning system into constraints. Second, an improved differential evolution algorithm is proposed to solve this problem. By referencing the gray wolf algorithm,the differential evolution algorithm updates individuals by varying toward the direction of multiple optimal values. Then, a new combination positioning algorithm for high-speed trains is proposed. In the simulation,the increase in positioning speed and accuracy is analyzed and validated. Compared to the current algorithms, the proposed algorithm performs better. The proposed method has practical value for improving the reliability and safety of train operations.

关键词： electronic map multi-objective optimization differential evolution algorithm Beidou navigation system high-speed train positioning

Single Peak Solutions for a Schr?dinger Equation with Variable Exponent

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Acta Mathematica Sinica,English Series 2023年第11期39卷 2207-2218页

作者： Zhong Yuan LIU Peng LUO hua Fei xie School of Mathematics and Statistics He’nan UniversityKaifeng 475004P.R.China School of Mathematics and Statistics&Hubei Key Laboratory of Mathematical Sciences Central China Normal UniversityWuhan 430079P.R.China School of Mathematics and Statistics Nanyang Normal UniversityNanyang 473061P.R.China

We study the following Schr?dinger equation with variable exponent−Δu+u=u^(p+∈a)(x),u>0 in R^(N),where∈>0,1 详细信息

We study the following Schr?dinger equation with variable exponent−Δu+u=u^(p+∈a)(x),u>0 in R^(N),where∈>0,1

关键词： Single peak solutions Schr?dinger equation variable exponent

Evolutionary under-sampling based bagging ensemble method for imbalanced data classification

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Frontiers of Computer Science 2018年第2期12卷 331-350页

作者： Bo SUN Haiyan CHEN Jiandong WANG Hua Xie College of Computer Science and Technology Nanjing University of Aeronautics and Astronautics Nanjing 210016 China National Key Lab of ATFM Nanjing University of Aeronautics and Astronautics Nanjing 211106 China

In the class imbalanced learning scenario, traditional machine learning algorithms focusing on optimizing the overall accuracy tend to achieve poor classification performance especially for the minority class in which we are most interested. To solve this problem, many effective approaches have been proposed. Among them, the bagging ensemble methods with integration of the under-sampling techniques have demonstrated better performance than some other ones including the bagging ensemble methods integrated with the over-sampling techniques, the cost-sensitive methods, etc. Although these under-sampling techniques promote the diversity among the generated base classifiers with the help of random partition or sampling for the majority class, they do not take any measure to ensure the individual classification performance, consequently affecting the achievability of better ensemble performance. On the other hand, evolutionary under-sampling EUS as a novel under- sampling technique has been successfully applied in searching for the best majority class subset for training a good- performance nearest neighbor classifier. Inspired by EUS, in this paper, we try to introduce it into the under-sampling bagging framework and propose an EUS based bagging ensemble method EUS-Bag by designing a new fitness function considering three factors to make EUS better suited to the framework. With our fitness function, EUS-Bag could generate a set of accurate and diverse base classifiers. To verify the effectiveness of EUS-Bag, we conduct a series of comparison experiments on 22 two-class imbalanced classification problems. Experimental results measured using recall, geometric mean and AUC all demonstrate its superior performance.

关键词： class imbalanced problem under-sampling bagging evolutionary under-sampling ensemble learning machine learning data mining

Bayesian inference of the crust–core transition density via the neutron-star radius and neutron-skin thickness data

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Nuclear Science and Techniques 2023年第6期34卷 125-133页

作者： Wen-Jie xie Zi-Wei Ma Jun-hua Guo Department of Physics Yuncheng UniversityYuncheng044000China

In this work,we perform a Bayesian inference of the crust-core transition density ρ_(t) of neutron stars based on the neutron-star radius and neutron-skin thickness data using a thermodynamical method.Uniform and Gaussian distributions for the ρ_(t) prior were adopted in the Bayesian approach.It has a larger probability of having values higher than 0.1 fm^(−3) for ρ_(t) as the uniform prior and neutron-star radius data were used.This was found to be controlled by the curvature K_(sym) of the nuclear symmetry energy.This phenomenon did not occur if K_(sym) was not extremely negative,namely,K_(sym)>−200 MeV.The value ofρ_(t) obtained was 0.075_(−0.01)^(+0.005) fm^(−3) at a confidence level of 68%when both the neutron-star radius and neutron-skin thickness data were considered.Strong anti-correlations were observed between ρ_(t),slope L,and curvature of the nuclear symmetry energy.The dependence of the three L-K_(sym) correlations predicted in the literature on crust-core density and pressure was quantitatively investigated.The most probable value of 0.08 fm^(−3) for ρ_(t) was obtained from the L-K_(sym) relationship proposed by Holt et al.while larger values were preferred for the other two relationships.

关键词： Crust–core transition density of neutron stars Neutron-star radius Neutron-skin thickness Bayesian inference approach L–K_(sym)

Static-feedback guaranteed cost control for linear systems with outage and loss of effectiveness actuator faults

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Journal of Control and Decision 2022年第4期9卷 407-419页

作者： Chun-Hua Xie Zhe Li Yanli Zhou School of Electrical and Automation Engineering East China Jiaotong UniversityNanchangPeople’s Republic of China Key Laboratory of Advanced Control&Optimization of Jiangxi Province NanchangPeople’s Republic of China cCollege of Electrical and Information Engineering Hunan UniversityChangshaPeople’s Republic of China

This paper investigates the static-feedback guaranteed cost control problem for linear systems with actuator faults including outage and loss of effectiveness.Under the actuator redundancy condition,theoretical analysis shows that a static-feedback guaranteed cost controller can always be well designed to ensure that the resulting closed-loop system is stable with desirable quadratic performance.In particular,the feedback gain can be determined through the solution of a modified algebraic Riccati equation.Furthermore,extension to the system with uncertainties is further studied.Compared with the dynamic feedback controller,the static-feedback controller consists only of logical gates/modules and it does not require any memory element,and hence it is simplest in a design perspective.Different from the existing results,the severe and timevarying actuator outage faults can be handled very well by the proposed control strategy.Finally,simulation on a linearised reduced-order aircraft system is provided for verifying the theoretical results.

关键词： Static-feedback guaranteed cost control linear systems actuator outage faults algebraic Riccati equation

Measurement of thermal conductivity,viscosity and density of ionic liquid [EMIM][DEP]-based nanofluids

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Chinese Journal of Chemical Engineering 2016年第3期24卷 331-338页

作者： Hua Xie Zongchang Zhao Jianhua Zhao Hongtao Gao School of Chemical Engineering Dalian University of Technology Institute of Marine Engineering and Thermal Science Dalian Maritime University

This article studied experimentally the effect of multi-wall carbon nanotubes(MWCNTs)on the thermo physical properties of ionic liquid-based nanofluids.The nanofluids were composed of ionic liquid,1-ethyl-3-methylimidazolium diethylphosphate [EMIM][DEP],or its aqueous solution[EMIM][DEP](1)+ H_2O(2)and MWCNTs without any surfactants.The thermal conductivity,viscosity and density of the nanofluids were measured experimentally.The effects of the mass fraction of MWCNTs,temperature and the mole fraction of water on the thermo physical properties of nanofluids were studied.Results show that the thermal conductivity of nanofluids increases within the range of 1.3%–9.7% compared to their base liquids,and have a well linear dependence on temperature.The viscosity and density of the nanofluids exhibit a remarkable increase compared with those of the base liquids.Finally,the correlation of the effective thermal conductivity and viscosity of the nanofluids was made using the models in the literatures.

关键词：导热系数测量纳米流体离子液体流体密度 DEP 粘度多壁碳纳米管热物理性质

Spectroscopic characterization of chain-to-ring structural evolution in platinum carbide clusters

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Journal of Energy Chemistry 2023年第2期77卷 529-534,I0014页

作者： Yu Zhang Shihu Du Zhi Zhao Haiyan Han Gang Li Jinghan Zou Hua Xie Ling Jiang State Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina College of Chemistry and Chemical Engineering Xinyang Normal UniversityXinyang 464000HenanChina School of Mathematics and Physics Hebei University of EngineeringHandan 056038HebeiChina

Metal carbides play an important role in catalysis and functional materials.However,the structural characterization of metal carbide clusters has been proven to be a challenging experimental target due to the difficulty in size selection.Here we use the size-specific photoelectron velocity-map imaging spectroscopy to study the structures and properties of platinum carbide clusters.Quantum chemical calculations are carried out to identify the structures and to assign the experimental spectra.The results indicate that the cluster size of the chain-to-ring structural evolution for the PtC_(n)^(-)anions occurs at n=14,whereas that for the PtC_(n) neutrals at n=10,revealing a significant effect of charge on the structures of metal carbides.The greatest importance of these building blocks is the strong preference of the Pt atom to expose in the outer side of the chain or ring,exhibiting the active sites for catalyzing potential reactions.These findings provide unique spectroscopic snapshots for the formation and growth of platinum carbide clusters and have important implications in the development of related single-atom catalysts with isolated metal atoms dispersed on supports.

关键词： Catalysis Functional material Metal carbide Photoelectron velocity-map imaging spectroscopy Quantum chemical calculation

CO activation by the heterobinuclear transition metal-iron clusters: A photoelectron spectroscopic and theoretical study

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Journal of Energy Chemistry 2021年第12期30卷 344-350,I0008页

作者： Jumei Zhang Zhiling Liu Gang Li Hongjun Fan Ling Jiang Hua Xie State Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina School of Life Science Ludong UniversityYantai 264025ShandongChina School of Chemical and Material Science Key Laboratory of Magnetic Molecules&Magnetic Information MaterialsMinistry of EducationShanxi Normal UniversityLinfen 041004ShanxiChina

Spectroscopic characterization of CO activation on multiple metal-containing catalysts remains an important and challenging goal for identifying the structure and nature of active site in many industrial processes such as Fischer-Tropsch chemistry and alcohol synthesis.Here,we use mass-selected photoelectron velocity-map imaging spectroscopy and quantum chemical calculations to study the reactions of CO molecules with several heterobinuclear transition metal-iron clusters M-Fe(M=Ti,V,Cr).The mass spectra reveal the favorable formation of MFe(CO)_(4)^(-)with relatively high thermodynamic stability.The MFe(CO)_(4)^(-)(M=Ti,V,Cr) complexes are established to have a metal-Fe bonded M-Fe(CO)_(4) structure with C_(3 v) geometry.While the positive charge and unpaired electrons are mainly located on the M atom,the natural charge of Fe(CO)_(4) is about-2 e.The MFe(CO)_(4)^(-)(M=Ti,V,Cr) can be seen as being formed via the interactions between the M^(+)fragment and the [Fe(CO)_(4)]^(2-)core,which satisfies the 18-electron rule.The CO molecules are remarkably activated in these MFe(CO)_(4)^(-).These results shed insight into the structure-reactivity relationship of heterobinuclear transition metal carbonyls and would have important implications for understanding of CO activation on alloy surfaces.

关键词： CO activation Metal carbonyl Alloy surface Photoelectron velocity-map imaging spectroscopy