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Raster-scanning Donut simplifies MINFLUX and provides alternative implement on other scanning-based microscopes

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Light(Science & Applications) 2022年第10期11卷 2271-2275页

作者： Xinzhu Xu shu jia Peng Xi Department of Biomedical Engineering College of Future TechnologyPeking UniversityBeijing 100871China Wallace H.Coulter Department of Biomedical Engineering Georgia Institute of Technology and Emory UniversityAtlantaGeorgia 30332USA UTS-SUStech Joint Research Centre for Bio-medical Materials&Devices Department of Biomedical EngineeringCollege of EngineeringSouthern University of Science and TechnologyShenzhenGuangdong 518055China National Biomedical Imaging Center Peking UniversityBeijing 100871China

A donut excitation moves around a single molecule with a zigzag configuration lattice by *** a method implemented in scanning fluorescence microscopy simplifies the conventional MINFLUX *** of hollow zero-intensity excitation,single-pixel detection,time-correlated single photon counting,and drift stabilization,the system achieves localization precision and resolution very close to conventional MINFLUX theoretically and *** averaged high-SNR reference,and pixel-registered intensity from a single molecule is essential to reconstruct localization in maximum likelihood *** performance reaching nearly conventional MINFLUX's,the proposed raster-scanning MINFLUX can inspire researchers expertized in STED or confocal setup to quickly transform to MINFLUX and develop for further exploring on bio-specimens or optical applications.

关键词： scanning excitation stabilization

Hybrid optimization for charge planning problem in twin strands continuous casting production

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Journal of Iron and Steel Research International 2021年第5期28卷 520-529页

作者： jian Yi shu-jin jia Bin Du College of Information Science and Engineering Northeastern UniversityShenyang 110819LiaoningChina Institute of Intelligent Manufacturing Baosteel Central Research InstituteShanghai 201900China

Charge planning is one of batching problems for steelmaking and continuous casting production,and its optimization will be conducive to subsequent cast *** planning problem in the twin strands continuous casting production was studied,where casting width of the odd strand might be different from that of the even *** the different widths in the twin strands,the resulting counterweights and the constraints of steelmaking and continuous casting,a multiobjective optimization model was established to minimize the number of charges,the number of scale pairs,the surplus and the upgrading costs of steel ***,a hybrid optimization algorithm combined with heuristic and mutation-based estimation of distribution algorithm was proposed to solve the *** were conducted on several groups of test data collected from practical production orders of *** computational results demonstrate that the proposed algorithm can generate better solutions than the manual *** proposed model and algorithm proved to be effective and practical.

关键词： Steelmaking Continuous casting Production planning Charge Cast Estimation of distribution algorithm

Mass Spectrometric Fragmentation of 1-(Benzyloxycarbonyl)amino-2-alkyl/cycloalkyl Thioacetates:a Thioester Pyrolysis-type Rearrangement under Electron Impact Ionization

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Chinese Chemical Letters 2006年第8期17卷 1069-1072页

作者： shu XU jia Xi XU Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education College of Chemistry and Molecular Engineering Peking University Beijing 100871

The mass spectrometric fragmentation of 1-（benzyloxycarbonyl）amino-2-alkyl/cycloalkyl thioacetates has been studied with the aid of mass-analysed ion kinetic energy spectrometry under electron impact ionization. All compounds show a tendency to eliminate a ketene, thioacetic acid, and benzyl carbamate molecule, or an acetyl and benzyloxy radicals. A thioester pyrolysis-type rearrangement under electron impact ionizations was observed.

关键词： Electron impact ionization mass spectrometry rearrangement thioacetate.

Relationship between microstructure and corrosion behavior of high-grade pipeline steel in a low-temperature environment

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Journal of Iron and Steel Research International 2021年第8期28卷 1037-1046页

作者： jia-qiang Jing Jie Guo Ba Li shu-jun jia Yi Ren School of Oil and Gas Engineering Southwest Petroleum UniversityChengdu 610500SichuanChina Department of Structural Steels Central Iron and Steel Research InstituteBeijing 100081China State Key Laboratory of Metal Material for Marine Equipment and Application of Iron and Steel Research Institutes of Ansteel Group Corporation Anshan 114009LiaoningChina

The relationship between micro structure and corrosion behavior of high-grade pipeline steel under low-temperature conditions was comparatively investigated by the potentiodynamic polarization and electrochemical impedance spec-troscopy test combining with optical micrographs,scanning electron microscopy,transmission electron microscopy and electron back-scattered *** results showed that,compared with room and high temperature,low temperature could influence the corrosion behavior of high-grade pipeline steel,which means that the corrosion potential and current density decreased and the corrosion resistance increased ***,double layer structures of the interface became thicker and more *** low-temperature environment,acicular ferrite had the martensite/austenite constituents with less amount and smaller size,a higher density of low angle grain boundaries and smaller effective grain sizes compared with granular bainite,which demonstrated higher corrosion resistance.

关键词： Low temperature High-grade pipeline steel Corrosion behavior Resistance Acicular ferrite Granular bainite Martensite/austenite constituent

A Facile Approach to Regioselective 1-O-Deacylation of Peracylated Glycopyranoses

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Chinese Chemical Letters 2003年第3期14卷 233-234页

作者： jia Qiang DONG shu jia ZHANG Yan Guang WANG Department of Chemistry Zhejiang UniversityHangzhou 310027

The regioselective 1-O-deacylation of peracylated glycopyranoses 1a-d with zinc chloride and zinc oxide in THF/MeOH gave the corresponding tetra-O-acylglycopyranoses 2a-d in good yields.

关键词： Hydroxy sugars oligosaccaride zinc chloride.

A Deprojection Analysis of Abell 1650 with XMM-Newton

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Chinese Journal of Astronomy and Astrophysics 2006年第2期6卷 181-196页

作者： shu-Mei jia Yong Chen Li Chen Department of Astronomy Beijing Normal University Beijing 100875 Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academyof Sciences Beijing 100049

We revisit the XMM-Newton observation of the galaxy cluster Abell 1650 with a deprojection technique. We find that the radial deprojected spectra of Abell 1650 can be marginally fitted by a single-temperature model. In order to study the properties of the central gas, we fit the spectra of the central two regions with a two- temperature model. The fits then become significantly better and the cool gas about 1～2 keV can be connected with the gas cooling. Fitting the central spectrum （r≤1′） by using a cooling flow model with an isothermal component yields a small mass deposition rate of 10-7^＋11 M. yr^-1, while the standard cooling flow model can not fit this spectrum satisfactorily except that there exists a cut-off temperature having a level of about 3 keV. From the isothermal model we derive the deprojected electron density profile ne（r）, and then together with the deprojected temperature profile the total mass and gas mass fraction of cluster are also determined. We compare the properties of Abell 1650 with those of Abell 1835 （a large cooling flow cluster） and some other clusters, to explore the difference in properties between large and small cooling flow cluster, and what causes the difference in the cooling flow of different clusters. It has been shown that Abell 1835 has a steeper potential well and thus a higher electron density and a lower temperature in its center, indicating that the shape of the gravitational potential well in central region determines the cooling flow rates of clusters. We calculate the potential, internal and radiated energies of these two clusters, and find that the gas energies in both clusters are conserved during the collapsing stage.

关键词： galaxies: clusters: individual: Abell 1650 -galaxies: cooling flowsgalaxies: evolution - galaxies: intergalactic medium - X-rays: galaxies: clusters

Predicting Chaotic Time Series Using Recurrent Neural Network

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Chinese Physics Letters 2000年第2期17卷 88-90页

作者： ZHANG jia-shu XIAO Xian-Ci Department of Electronic Engineering University of Electronic Science and Technology of ChinaChengdu610054

A new proposed method, i.e. the recurrent neural network (RNN), is introduced to predict chaotic time series. The effectiveness of using RNN for making one-step and multi-step predictions is tested based on remarkable few datum points by computer-generated chaotic time series. Numerical results show that the RNN proposed here is a very powerful tool for making prediction of chaotic time series.

关键词： series computer neural

Predicting Hyper-Chaotic Time Series Using Adaptive Higher-Order Nonlinear Filter

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Chinese Physics Letters 2001年第3期18卷 337-340页

作者： ZHANG jia-shu XIAO Xian-Ci Department of Electronic Engineering University of Electronic Science and Technology of ChinaChengdu 610054

A newly proposed method,*** adaptive higher-order nonlinear finite impulse response(HONFIR)filter based on higher-order sparse Volterra series expansions,is introduced to predict hyper-chaotic time *** effectiveness of using adaptive HONFIR filter for making one-step and multi-step predictions is tested based on very few data points by computer-generated hyper-chaotic time series including Mackey-Glass equation and 4-dimensional nonlinear dynamical system.A comparison is made with some neural networks for predicting the Mackey-Glass hyper-chaotic time *** simulation results show that the adaptive HONFIR filter proposed here is a very powerful tool for making prediction of hyper-chaotic time series.

关键词： chaotic nonlinear Nonlinear

Multi-objective model and optimization algorithm based on column generation for continuous casting production planning

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Journal of Iron and Steel Research International 2019年第3期26卷 242-250页

作者： jian Yi shu-jin jia Bin Du Qing Liu Institute of Intelligent Manufacturing Baosteel Central Research Institute Shanghai 201900 China College of Information Science and Engineering Northeastern UniversityShenyang 110819 LiaoningChina State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing Beijing 100083 China

The optimization of continuous casting production planning(CCPP)in the steel industry was *** essence of CCPP is the productive capability balance of back-end facilities over the planning time *** facilities with the demands of productive capability are called the *** the basis of charge plans,the task of CCPP is to produce cast plans according to the rules of cast design in order to meet the ***,a multi-objective model was established with considering the demands of flows,the capability requirements of liquid steel refini ng devices,and the rules of cast ***,the model was decomposed into a master problem(set partitioning problem model)and a series of subproblem(pricing problem model)by using Dantzig-Wolfe decomposition ***,a column generation-based optimization algorithm(CGBOA)was *** experimental results on practical production data from Baosteel demonstrate that the proposed algorithm is effective and ***,a new decision support system based on CGBOA has been successfully established and applied to No.2 Steelmaking Plant at Baosteel.

关键词： Steelmaking Continuous casting Production planning Charge Cast Column generation