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Rare Metals 2019年第5期38卷 369-378页

作者： Ying chen shi Li Ruo-Yu Zhao Wei Li Zhao-Hui Ren Gao-rong Han State Key Laboratory of Silicon Materials School of Materials Science and Engineering Cyrus Tang Center for Sensor Materials and Application Zhejiang University

Vertically aligned TiO2/SrTiO3 core–shell heterostructured nanowire arrays with different shell thicknesses(5–40 nm)were fabricated on fluorine-doped tin oxide substrate via a hydrothermal *** characterization demonstrated that the TiO2 nanowires were uniformly coated by the singlecrystal SrTiO3 shell,where continuous and large-area interface could be clearly *** this means,significantly enhanced photoelectrochemical water splitting properties(0.78 mA·cm^-2 at 1.23 V ***)were successfully realized in well-designed sample(with a shell thickness of 5–10 nm)compared with those of pristine TiO2(0.38 mA·cm^-2 at 1.23 V ***).The improvement of photoelectrochemical properties was attributed to the improved charge injection and charge separation,which are calculated by the results of water oxidation and sulfite oxidation *** on these results,a mechanism was proposed that SrTiO3 shell acted as an electron–hole separation layer to improve the photocurrent *** the other hand,the sample with an over-thick SrTiO3 shell(20–40 nm)exhibited slightly reduced photoelectrochemical properties(0.66 mA·cm^-2),which could be explained by the increase of the recombination rate in thethicker SrTiO3 *** work provided a facile strategy to improve and modulate the photoelectrochemical performance of heterostructured photoanodes.

关键词： TiO2/SrTiO3 heterostructured nanowire arrays Photoelectrochemical water splitting Shell thickness Band alignment

Universal FRFT-based algorithm for parameter estimation of chirp signals

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Journal of Systems Engineering and Electronics 2012年第4期23卷 495-501页

作者： rong chen Yiming Wang School of Electronics and Information Engineering Soochow UniversitySuzhou 215006P.R.China National Laboratory of Information Control Technology for Communication System Jiaxing 314001P.R.China

The realization of the parameter estimation of chirp signals using the fractional Fourier transform （FRFT） is based on the assumption that the sampling duration of practical observed signals would be equal to the time duration of chirp signals contained in the former. However, in many actual circumstances, this assumption seems unreasonable. On the basis of analyzing the practical signal form, this paper derives the estimation error of the existing parameter estimation method and then proposes a novel and universal parameter estimation algorithm. Furthermore, the proposed algorithm is developed which allows the estimation of the practical observed Gaussian windowed chirp signal. Simulation results show that the new algorithm works well.

关键词： fractional Fourier transform (FRFT) chirp signal,parameter estimation observation window.

Formation and capturing of nanoparticles in Cu-1wt.%Fe alloy melt during directional solidification process

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Journal of Iron and Steel Research International 2017年第4期24卷 411-415页

作者： Tao Wang Xiao-hua chen Guo-dong shi Chang-rong Li Zi-dong Wang School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China

A single crystal Cu-1wt.%Fe alloy with finely dispersed iron-rich nanoparticles which keep coherent interface with the copper matrix was prepared under directional *** of nanoparticles in the alloy melt was investigated by performing differential scanning calorimeter tests and designed water quenching experiment at a certain *** show that iron-rich nanoparticles are formed in the Cu-1wt.%Fe alloy melt before primaryα-Cu forms,which is not consistent with equilibrium phase *** that iron-rich nanoparticles are uniformly captured in the matrix was described,which is that numerous nanoparticles follow Brownian motions and are engulfed in the solidified matrix which makes it possible to form uniformly distributed nanoparticles reinforced single crystal Cu-1wt.%Fe alloy.

关键词： Single crystal Copper alloy Nanoparticle Coherent interface Brownian motion

C-Glycoside Synthesis Enabled by Nickel Catalysis

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Chinese Journal of Chemistry 2023年第17期41卷 2217-2236页

作者： Weidong Shang rong shi Dawen Niu Targeted Tracer Research and Development Laboratory Institute of Respiratory HealthState Key Laboratory of Biotherapy and Cancer Center West China Hospital and Schoolof Chemical EngineeringSichuan UniversityChengduSichuan 610041China State Key Laboratory of Biotherapy and Cancer Center West China Hospital and Department of Chemical EngineeringSichuan UniversityChengduSichuan 610041China

Comprehensive Summary,C-Glycosides are critical,naturally occurring products and medicinal candidates,and extensive efforts have been made to explore efficient approaches for creating C-glycosidic ***-metal-catalysis,particularly nickel-catalyzed C-glycosylation reactions constitute a promising ***,achieving a stereoselective synthesis ofα-andβ-C-glycosides has been a long-standing *** address this problem,a variety of nickel-mediated strategies have been *** review highlights recent developments in the nickel-catalyzed diastereoselective C-glycosylation reactions and briefly summarizes the mechanistic understandings of these methods.

关键词： C-Glycosides Nickel Glycosylation Glycosyl radical Carbohydrates

On-Abnormal Maximal Subgroups of Finite Groups

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Acta Mathematica Sinica,English Series 2007年第5期23卷 885-888页

作者： shi rong LI Department of Mathematics Guangxi University Nanning 530004 P. R. China

For any saturated formation F of finite groups containing all supersolvable groups, the groups in F are characterized by F-abnormal maximal subgroups.

关键词： finite group saturated formation F-abnormal maximal subgroup Deskins completion

Synthesis and Crystal Structure of 1-(4-Chlorophenyl)-2-cyano-3-amino-3a-hydroxy- 3a,3b,6,7-tetrahydrobenzo[4,5]indene

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Chinese Journal of Structural Chemistry 2005年第12期24卷 1393-1396页

作者： shi Da-Qing shi Chun-Ling rong Liang-Ce Department of Chemistr） Xuzhou Normal University Xuzhou 221116 China The Key Laboratory of Biotechnology on Medical Plants of Jiangsu Province Xuzhou 221116 China

The title compound 1-（4-chlorophenyl）-2-cyano-3-amino-3a-hydroxy-3a,3b,6,7- tetrahydro-benzo[4,5]indene 2, has been synthesized by the reductive cyclization of 2-cyano-3- （4-chlorophenyl）-3-（1-tetralon-2-yl） propionitrile 1 induced by low-valent titanium reagent and its structure was determined by single-crystal X-ray diffraction. The crystal belongs to monoclinic, space group C2/c with a = 28.244（7）, b = 14.401（3）, c = 21.245（3）A,β= 115.71（2）°, V = 7786（3）A^3, Mr= 696.13, Dc = 1.188 g/cm^3, Z = 8,μ（MoKα） = 0.208 mm^-1, F（000） = 2916, R = 0.0783 and wR = 0.2350. X-ray analysis reveals that the five-membered ring （C（7）～C（l l）） adopts an envelop conformation, while the six-membered ring （C（10）～C（14）, C（19）） has a half-chair conformation. Meanwhile, intermolecular H-bond interactions result in the formation of polymer.

关键词： tetrahydrobenzoindene synthesis crystal structure low-valent titanium

Finite Element Analysis of 100 t Hot Metal Ladle in Process of Tipping

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Journal of Iron and Steel Research International 2010年第11期17卷 19-23页

作者： TIAN Hong-yu chen Fu-rong XIE Rui-jun LI shi-hui College of Materials Science and Engineering Inner Mongolia University of Technology Hohhot 010051 Inner Mongolia China Department of Mechanical and Electrical Engineering Baotou Light Industry Vocational and Technical College Baotou 014035 Inner Mongolia China

Hot metal ladle is an important part in continuous casting production line and its stress distribution has direct influence on its life. In the process of design and calibration of the large-sized hot metal ladle, it is of great significance to determine the stress distribution of each part of the ladle for safely and reliably running the device. Based on 100 t hot metal ladle which is designed by Baotou Iron and Steel Group, simulation of stress field was made by finite element software ANSYS 10.0 from different dumping angles. Through modeling, loading, restricting and calculating, strain and stress field distribution of the hot metal ladle were acquired. Finally, an assessment of strength and stiffness was made on the hot metal ladle. The results show that in the process of tipping for the hot metal ladle, maximum stress is 132 MPa and maximum strain is only 0. 064% ; maximum stress and strain have appeared in the stiffener plate which is located at the bottom of the trunnion, and strength and stiffness are qualified. The method, which is convenient and practical, reasonable and reliable, provides theoretical evidence for checking analysis and further optimal design of the hot metal ladle.

关键词： hot metal ladle stress field finite element analysis

The rice PLATZ protein SHORT GRAIN6 determines grain size by regulating spikelet hull cell division

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Journal of Integrative Plant Biology 2020年第6期62卷 847-864页

作者： shi-rong Zhou Hong-Wei Xue National Key Laboratory of Plant Molecular Genetics CAS Center for Excellence in Molecular Plant SciencesShanghai Institute of Plant Physiology and Ecologythe Chinese Academy of SciencesShanghai 200032China State Key Laboratory of Crop Genetics and Germplasm Enhancement Jiangsu Plant Gene Engineering Research CenterNanjing Agricultural UniversityNanjing 210095China School of Agriculture and Biology Shanghai Jiao Tong UniversityShanghai 200240China

Grain size is a major determinant of cereal grain yields;however,the relevant regulatory mechanisms controlling this trait have not been fully *** rice(Oryza sativa)mutant short grain6(sg6)was identified based on its reduced grain length and ***,we functionally characterized the role of SG6 in determining grain size through the regulation of spikelet hull cell ***6 encodes a previously uncharacterized plant ATrich sequence and zinc-binding(PLATZ)protein that is ubiquitously localized throughout the cell and is preferentially expressed in the early developing panicles but not in the *** overexpression of SG6 resulted in significantly larger and heavier grains,as well as increased plant heights,which is consistent with its elevated spikelet hull cell division *** two-hybrid analyses revealed that SG6 interacts with the core cell cycle machinery DP protein and several other putative cell division regulators,consistent with our transcriptomic analysis,which showed that SG6 activates the expression of many DNA replication and cell-cycle-related *** results confirm the crucial role of SG6 in determining grain size by regulating spikelet hull cell division and provide clues for understanding the functions of PLATZ family proteins and the network regulating cereal grain size.

关键词： sativa) fir cereal

Multiphonon-resonance quantum Rabi model and adiabatic passage in a cavity-optomechanical system

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Frontiers of physics 2022年第1期17卷 79-87页

作者： Zhi-rong Zhong Lei chen Jian-Qi Sheng Li-Tuo Shen shi-Biao Zheng Fujian Key Laboratory of Quantum Information and Quantum Optics College of Physics and Information EngineeringFuzhou UniversityFuzhou350108China

In this paper,we propose a scheme to achieve a multiphonon-resonance quantum Rabi model and adiabatic passage in a strong-coupling cavity optomechanical *** the scheme,when the driving bichromatic laser beam is adjusted to the off-resonant j-order red-and blue-sideband,the interaction between the cavity and mechanical oscillator leads to a j-phonon resonance quantum Rabi ***,we show that there exists a resonant multi-phonon coupling via intermediate states connected by counter-rotating processes when the frequency of the simulated bosonic mode is near a fraction of the transition frequency of the simulated two-level *** a typical example,we theoretically analyze the two-phonon resonance quantum Rabi model,and derive an effective Hamiltonian of the six-phonon ***,we present a method of six-phonon generation based on adiabatic passage across the *** simulations confirm the validity of the proposed ***,the proposed scheme can be extended to the realization of 3j-phonon state.

关键词： quantum Rabi model cavity-optomechanical system adiabatic passage

Finite-time tracking control and vibration suppression based on the concept of virtual control force for flexible two-link space robot

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Defence Technology（防务技术） 2021年第3期17卷 874-883页

作者： rong-Hua Lei Li chen School of Mechanical Engineering and Automation Fuzhou UniversityFuzhou350116China

The dynamic modeling, finite-time trajectory tracking control and vibration suppression of a flexible two-link space robot are studied. Firstly, the dynamic model of the system is established by combining Lagrange method with assumed mode method. In order to ensure that the base attitude and the joints of space robot can reach the desired positions within a limited time, a non-singular fast terminal sliding mode(NFTSM) controller is designed, which realizes the finite-time convergence of the trajectory tracking errors. Subsequently, for the sake of suppressing the vibrations of flexible links, a hybrid trajectory based on the concept of the virtual control force is developed, which can reflect the flexible modes and the trajectory tracking errors simultaneously. By modifying the original control scheme, a NFTSM hybrid controller is proposed. The hybrid control scheme can not only realized attitude stabilization and trajectory tracking of joints in finite time, but also provide a new method of vibration suppression. The simulation results verify the effectiveness of the designed hybrid control strategy.

关键词： Finite-time Terminal sliding mode Flexible links Vibration suppression Virtual control force