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Nano Research 2024年第4期17卷 2360-2367页

作者： Xiao-yan Li Manyi Duan Pengfei Ou Department of Electrical and Computer Engineering University of TorontoTorontoOntario M5S 1A4Canada School of Physics and Electronic Engineering Sichuan Normal UniversityChengdu 610101China Department of Chemistry Northwestern UniversityEvanstonIL 60208USA

The discovery of metal-nitrogen centers as the active sites for electrolysis has aroused significant interest in utilizing single-atom catalysts for nitrogen reduction reaction(NRR).Properly designed nanostructured catalysts that strongly interact with nitrogen molecules(N_(2))can promote adsorption and activation,thereby resulting in efficient catalysts with high stability,activity,and *** this study,using density functional theory calculations,we selected monolayer black phosphorus(BP)as the substrate and screened a series of single-atom transition metals confined in tri-coordinated and tetra-coordinated active centers(without and with N dopants)to electro-catalyze *** a result,we have identified two promising candidates(Hf_(1)-N_(1)P_(2)-1 and Tc_(1)-N_(4)),which exhibit not only low overpotentials of 0.56 and 0.49 V but also high thermodynamic and electrochemical stability,as well as good selectivity towards NRR over the competing hydrogen evolution *** also demonstrate the ability of Hf_(1)-N_(1)P_(2)-1 and Tc_(1)-N_(4) to activate and hydrogenate N_(2) by donating electrons and regulating charge *** study not only predicts new BP-based promising catalysts but also provides guidance for the rational design of high-performance NRR electrocatalysts under ambient conditions.

关键词： N_(2) electroreduction reaction single-atom catalysts black phosphorus density functional theory high-throughput calculations

Model-driven path planning for robotic plasma cutting of branch pipe with single Y-groove based on pipe-rotating scheme

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Advances in Manufacturing 2024年第1期12卷 94-107页

作者： yan Liu Qiu Tang Xin-Cheng Tian School of Control Science and Engineering Shandong UniversityJinan250061People’s Republic of China Engineering Research Center of Intelligent Unmanned System Ministry of EducationJinan250061People’s Republic of China School of Mechanical and Electronic Engineering Shandong Jianzhu UniversityJinan250101People’s Republic of China

The automatic cutting of intersecting pipes is a challenging task in *** improved automation and accuracy,this paper proposes a model-driven path planning approach for the robotic plasma cutting of a branch pipe with a single ***,it summarizes the intersection forms and introduces a dual-pipe intersection *** on this model,the moving three-plane structure(a description unit of the geometric characteristics of the intersecting curve)is constructed,and a geometric model of the branch pipe with a single Y-groove is ***,a novel mathematical model for plasma radius and taper compensation is ***,the compensation model and groove model are integrated by establishing movable ***,to prevent collisions between the plasma torch and workpiece,the torch height is planned and a branch pipe-rotating scheme is *** the established models and moving frames,the planned path description of cutting robot is provided in this novel *** accuracy of the proposed method is verified by simulations and robotic cutting experiments.

关键词： Automatic groove cutting of intersecting pipes Model-driven robot path planning Plasma beam radius and taper compensation

Integrated separation-electrochemical detection device based on wood column for online identification of enantiomer

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Nano Research 2024年第3期17卷 1893-1901页

作者： Junli Guo Yuanfei Xue Chenxi Zhao Junjian Zhao Zhida Gao Ye Mei yan-yan Song College of Sciences Northeastern UniversityShenyang 110004China State Key Laboratory of Precision Spectroscopy School of Physics and Electronic ScienceEast China Normal UniversityShanghai 200062China NYU-ECNU Center for Computational Chemistry at NYU Shanghai Shanghai 200062China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China

Chiral chemicals have attracted significant interest in the pharmaceutical industry,yet the separation methods to get pure enantiomers from racemic mixture are still *** date,the separation of enantiomers still mainly depends on chromatography using high-cost chiral stationary ***,wood channels were used as the handheld integrated device,and enantiomer separation was simultaneously detected using an electrochemical *** this method,a chiral UIO-66(L-UIO-66)modified enantiomer separation zone and carbonized wood based online detection zone are integrated along a single wood *** on the in situ separation results from the chronoamperometry data,the wood device shows excellent separation ability for a wide range of electrochemically active enantiomers,including 3,4-dihydroxyphenylalanine,amino acids,ascorbic acid,carnitine,and penicillamine with high chirality *** unbiased molecular dynamic simulations indicate that the excellent chiral recognition and separation are attributed to the different barriers from the bound states to the dissociated state of the enantiomers in the homochiral microenvironment of the *** integrated enantiomer separation-electrochemical detection device provides a novel,easy,and low-cost platform for the separation of pure enantiomer from racemic mixture.

关键词： wood column integrated separation-detection device enantioselectivity online sensing free energy barrier

Discriminative low-rank embedding with manifold constraint for image feature extraction and classification

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Optoelectronics Letters 2024年第5期20卷 299-306页

作者： yan Chunman WEI Shuhong School of Physics and Electronic Engineering Northwest Normal UniversityLanzhou 730070China Engineering Research Center of Gansu Province for Intelligent Information Technology and Application Lanzhou 730070China

The robustness against noise, outliers, and corruption is a crucial issue in image feature extraction. To address this concern, this paper proposes a discriminative low-rank embedding image feature extraction algorithm. Firstly, to enhance the discriminative power of the extracted features, a discriminative term is introduced using label information, obtaining global discriminative information and learning an optimal projection matrix for data dimensionality reduction. Secondly, manifold constraints are incorporated, unifying low-rank embedding and manifold constraints into a single framework to capture the geometric structure of local manifolds while considering both local and global information. Finally, test samples are projected into a lower-dimensional space for classification. Experimental results demonstrate that the proposed method achieves classification accuracies of 95.62%, 95.22%, 86.38%, and 86.54% on the ORL, CMUPIE, AR, and COIL20 datasets, respectively, outperforming dimensionality reduction-based image feature extraction algorithms.

关键词： manifold embedding dimensionality

Heterogeneous information phase space reconstruction and stability prediction of filling body–surrounding rock combination

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International Journal of Minerals,Metallurgy and Materials 2024年第7期31卷 1500-1511页

作者： Dapeng Chen Shenghua Yin Weiguo Long Rongfu yan Yufei Zhang Zepeng yan Leiming Wang Wei Chen School of Civil and Resources Engineering University of Science and Technology of BeijingBeijing 100083China Production Technology Department Longshou MineJinchuan Group Co.Ltd.Jinchang 737100China School of Civil Engineering and Architecture East China Jiaotong UniversityNanchang 330013China

Traditional research believes that the filling body can effectively control stress concentration while ignoring the problems of unknown stability and the complex and changeable stress distribution of the filling body–surrounding rock combination under high-stress *** monitoring data processing methods cannot fully consider the complexity of monitoring objects,the diversity of monitoring methods,and the dynamics of monitoring *** solve this problem,this paper proposes a phase space reconstruction and stability prediction method to process heterogeneous information of backfill–surrounding rock *** three-dimensional monitoring system of a large-area filling body–surrounding rock combination in Longshou Mine was constructed by using drilling stress,multipoint displacement meter,and *** information,such as the stress and displacement of the filling body–surrounding rock combination,was continuously *** with the average mutual information method and the false nearest neighbor point method,the phase space of the heterogeneous information of the filling body–surrounding rock combination was then *** this paper,the distance between the phase point and its nearest point was used as the index evaluation distance to evaluate the stability of the filling body–surrounding rock *** evaluated distances(ED)revealed a high sensitivity to the stability of the filling body–surrounding rock *** new method was then applied to calculate the time series of historically ED for 12 measuring points located at Longshou *** moments of mutation in these time series were at least 3 months ahead of the roadway return *** the ED prediction experiments,the autoregressive integrated moving average model showed a higher prediction accuracy than the deep learning models(long short-term memory and Transformer).Furthermore,the root-mean-square error distribution of the prediction results peaked at 0

关键词： deep mining filling body–surrounding rock combination phase space reconstruction multiple time series stability prediction

Research on casing deformation prevention technology based on cementing slurry system optimization

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Petroleum Science 2024年第2期21卷 1231-1240页

作者： yan yan Meng Cai Wen-Hai Ma Xiao-Chuan Zhang Li-Hong Han Yong-Hong Liu State Key Laboratory for Performance and Structure Safety of Petroleum Tubular Goods and Equipment Materials CNPC Tubular Goods Research InstituteXi©an710077ShaanxiChina College of Mechanical and Electrical Engineering China University of Petroleum(East China)Qingdao266580ShandongChina Shale Gas Evaluation and Exploitation Key Laboratory of Sichuan Province Chengdu610095SichuanChina CNPC Daqing Oilfield Company Daqing163453HeilongjiangChina

The casing deformation prevention technology based on the optimization of cement slurry is proposed to reduce the casing deformation of shale oil and gas wells during hydraulic fracturing. In this paper, the fracture mechanism of hollow particles in cement sheath was firstly analyzed by discrete element method, and the effect of hollow particles in cement on casing deformation was investigated by laboratory experiment method. Finally, field test was carried out to verify the improvement effect of the casing deformation based on cement slurry modification. The results show that the formation displacement can be absorbed effectively by hollow particles inside the cement transferring the excessive deformation away from casing. The particles in the uncemented state provide deformation space during formation slipping. The casing with diameter of 139.7 mm could be passed through by bridge plug with the diameter of 99 mm when the mass ratio of particle/cement reaches 1:4. According to the field test feedback, the method based on optimization of cement slurry can effectively reduce the risk of casing deformation, and the recommended range of hollow microbeads content in the cement slurry is between 15% and 25%.

关键词： Cement slurry Hollow ceramsite Casing deformation Formation slip Field test

High-Order Decoupled and Bound Preserving Local Discontinuous Galerkin Methods for a Class of Chemotaxis Models

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Communications on Applied Mathematics and Computation 2024年第1期6卷 372-398页

作者： Wei Zheng yan Xu School of Mathematical Sciences University of Science and Technology of ChinaHefei230026AnhuiChina

In this paper,we explore bound preserving and high-order accurate local discontinuous Galerkin(LDG)schemes to solve a class of chemotaxis models,including the classical Keller-Segel(KS)model and two other density-dependent *** use the convex splitting method,the variant energy quadratization method,and the scalar auxiliary variable method coupled with the LDG method to construct first-order temporal accurate schemes based on the gradient flow structure of the *** semi-implicit schemes are decoupled,energy stable,and can be extended to high accuracy schemes using the semi-implicit spectral deferred correction *** bound preserving DG discretizations are only worked on explicit time integration methods and are difficult to get high-order *** overcome these difficulties,we use the Lagrange multipliers to enforce the implicit or semi-implicit LDG schemes to satisfy the bound constraints at each time *** bound preserving limiter results in the Karush-Kuhn-Tucker condition,which can be solved by an efficient active set semi-smooth Newton *** numerical experiments illustrate the high-order accuracy and the effect of bound preserving.

关键词： Chemotaxis models Local discontinuous Galerkin(LDG)scheme Convex splitting method Variant energy quadratization method Scalar auxiliary variable method Spectral deferred correction method

High-temperature dielectric polymer composite for high power energy storage applications

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Science China Chemistry 2024年第8期67卷 2425-2426页

作者： Xiangyan Yu Haixue yan School of Engineering and Materials Science Queen Mary University of LondonLondon E14NSUK

Polymer-based dielectric films are the main component of dielectric capacitors due to their high power density, which plays an important role in power electrical systems using renewable energy, such as electric vehicles, solar panel, wind power [1]. However, the energy density of dielectrics is lower than that of other energy storage materials, such as batteries or supercapacitors. High energy density of the dielectric is related to high dielectric permittivity and high dielectric breakdown strength (DBS).

关键词： composite dielectric energy

Real-time model correction using Kalman filter for Raman-controlled cell culture processes

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Chinese Journal of Chemical Engineering 2024年第6期70卷 251-260页

作者： Xiaoxiao Dong Zhuohong He Xu yan Dong Gao Jingyu Jiao yan Sun Haibin Wang Haibin Qu Pharmaceutical Informatics Institute College of Pharmaceutical SciencesZhejiang UniversityHangzhou 310058China Hisun Biopharmaceutical Co.Ltd. Hangzhou 311404China

Raman spectroscopy has found extensive use in monitoring and controlling cell culture *** this context,the prediction accuracy of Raman-based models is of paramount ***,models established with data from manually fed-batch cultures often exhibit poor performance in Raman-controlled ***,there is a need for effective methods to rectify these *** objective of this paper is to investigate the efficacy of Kalman filter(KF)algorithm in correcting Raman-based models during cell ***,partial least squares(PLS)models for different components were constructed using data from manually fed-batch cultures,and the predictive performance of these models was ***,various correction methods including the PLS-KF-KF method proposed in this study were employed to refine the PLS ***,a case study involving the auto-control of glucose concentration demonstrated the application of optimal model correction *** results indicated that the original PLS models exhibited differential performance between manually fed-batch cultures and Raman-controlled *** glucose,the root mean square error of prediction(RMSEP)of manually fed-batch culture and Raman-controlled culture was 0.23 and 0.40 g·L^(-1).With the implementation of model correction methods,there was a significant improvement in model performance within Raman-controlled *** RMSEP for glucose from updating-PLS,KF-PLS,and PLS-KF-KF was 0.38,0.36 and 0.17 g·L^(-1),***,the proposed PLS-KF-KF model correction method was found to be more effective and stable,playing a vital role in the automated nutrient feeding of cell cultures.

关键词： Raman spectroscopy Model correction Algorithm Model-predictive control Bioprocess

The impact of water quality on the formation of halogenated benzoquinones and the adsorption efficiency by activated carbon

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Journal of Environmental Sciences 2024年第1期135卷 693-702页

作者： Yongjing Wang Song Gao Xinyu yan Songtao Wang Ruolin Zhang yan Zhou Lianhai Ren Cheng Li State Environmental Protection Key Laboratory of Food Chain Pollution Control Beijing Technology and Business UniversityBeijing 100048China Institute of Scientific and Technical Information of China Beijing 100038China Institute of Quality Standard and Testing Technology Beijing Academy of Agriculture and Forestry SciencesBeijing 100097China Key Laboratory of Cleaner Production and Integrated Resource Utilization of China National Light Industry Beijing Technology and Business UniversityBeijing 100048China

Halogenated benzoquinones(HBQs)could cause bladder cancer,but there were few related studies on the generation and *** this study,the impact of different precursors,pH,bromide concentration,and algae-derived organic matters on the formation of HBQs and the removal efficiency by activated carbon were *** was found that the chlorination of bisphenol A produced the most 2,6-dichloro-1,4-benzoquinone(2,6-DCBQ),reaching 14.86μg/L at 1 hr,followed by tyrosine,2-chlorophenol,P-hydroxybenzoic acid,trichlorophenol,and *** production of 2,6-DCBQ increased first and then decreased from 0 to 36 hr(chlorination doses 0-20 mg/L),indicating that HBQs were unstable in ***(THMs)were detected during chlorination,and the concentration increased with prolongation of reaction time.2,6-DCBQ production decreased and 2,6-dibromo-1,4-benzoquinone(2,6-DBBQ)production increased with increment bromide concentration and the bromide promoted the formation of *** production of 2,6-DCBQ decreased with increase of pH,and the maximum production was 141.38μg/L at pH of *** aeruginosa,Chlorella algae cells,and intracellular organic matters(IOM)could be chlorinated as potential precursors for *** most amount of 2,6-DCBQ was generated from algae cells of Microcystis aeruginosa,followed by Chlorella algae cells,Microcystis aeruginosa IOM,and Chlorella *** study compared the removal efficiency of HBQs by granular activated carbon(GAC)and columnar activated carbon(CAC)under different carbon doses and initial concentrations of *** was found that the removal efficiency by GAC(80.1%)was higher than that by CAC(51.8%),indicating that GAC has better control for HBQs.

关键词： HBQS DBPS Drinking water Algae derived organic matters Activated carbon