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Journal of Wuhan University of Technology(Materials Science) 2014年第3期29卷 612-616页

作者：余宏谢泉 chen qian Institute of Advanced Optoelectronic Materials and Technology College of Science Guizhou University School of Physical Education Sciences Guizhou Normal College

Mg films of various thicknesses were deposited on Si（111） substrates at room temperature by resistive thermal evaporation method, and then the Mg/Si samples were annealed at 40 ℃ for 4 h. The effects of Mg film thickness on the formation and structure of Mg2Si films were investigated. The results showed that the crystallization quality of Mg2Si films was strongly influenced by the thickness of Mg film. The XRD peak intensity of Mg2Si （220） gradually increased initially and then decreased with increasing Mg film thickness. The XRD peak intensity of Mg2Si （220） reached its maximum when the Mg film of 380 um was used. The thickness of the Mg2Si film annealed at 400℃ for 4 h was approximately 3 times of the Mg film.

关键词： Mg film thickness Mg2Si films Mg2Si films thickness thermal evaporation annealing

Theoretical studies on alloying of germanene supported on Al (111) substrate

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Chinese Physics B 2020年第10期29卷 521-534页

作者： qian-Xing chen Hao Yang Gang chen Laboratory of Advanced Materials Physics and Nanodevices School of Physics and TechnologyUniversity of JinanJinan 250022China School of Physics and Electronics Shandong Normal UniversityJinan 250358China

Using density functional theory,we study the alloying of the buckled hexagonal germanene superlattice supported on Al(111)-(3×3),the sheet composed of triangular,rhombic,and pentagonal motifs on Al(111)-(3×3),and the buckled geometry on Al(111)-(√7×√7)(19°),which are denoted,respectively,by BHS,TRP,and SRT7,to facilitate the discussion in this *** could be alloyed in the low doping concentration *** stable configurations BHS,TRP,and SRT7 of the pure and alloyed germanenes supported on both Al(111) and its Al2 Ge surface alloy,except the SRT7 pure germanene on Al2 Ge,could re-produce the experimental scanning tunneling microscopy *** relatively stable AlGe alloy species are the Al3 Ge5 BHS-2 T,Al3 Ge5 TRP-2 T,and Al3 Ge3 SRT7-1 T on Al(111) while they are the Al4 Ge4 BHS-1 T,Al3 Ge5 TRP-2 T,and A127 Ge27 SRT7-(3×3)-9 T on Al2 Ge(the n in the nT means that there are n Ge atoms per unit which sit at the top sites and protrude upward).In addition,the Al3 Ge5 BHS-2 T and Al4 Ge4 BHS-1 T are the most stable alloy sheets on Al(111) and Al2 Ge,*** with the experimental studies,there exists no structural transition among these alloyed configurations,which suggests that the experimental conditions play a crucial role in selectively growing the pure or the alloyed germanene sheets,which may also help grow the one-atomic thick honeycomb structure on idea Al(111).

关键词： first-principles calculation alloyed two-dimensional material substrate for two-dimensional material growth two-dimensional nanostructure

Aqueous Room-Temperature Phosphorescence from Assembled Phosphors for Analytical Detection

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Chinese Journal of Chemistry 2023年第8期41卷 979-990页

作者： Peisheng Cao qian chen Peng Wu College of Chemistry Sichuan UniversityChengduSichuan610064 China Analytical&Testing Center State Key Laboratory of Hydraulics and Mountain River EngineeringSichuan UniversityChengduSichuan610064 China School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiangHenan453007 China

Comprehensive Summary Room-temperature phosphorescence(RTP)has gained much attention in organic light-emitting diodes(OLEDs),anti-counterfeiting,encryption and ***,efficient RTP is typically difficult due to the spin-forbidden transition nature and susceptibility to environment *** aqueous phase,such quenching is much more pronounced,leading to the collection of aqueous RTP even more *** systems(either organic or inorganic),provide an excellent microenvironment for accommodating of phosphors in aqueous phase,due to the excluding of typical phosphorescence quenchers(H2O and O2)and rigidification of phosphorescent molecules for inhibition of non-radiative transitions(molecular motions).Herein,we summarized the recent progress in harvesting RTP from aqueous systems via various assembling strategies,including small molecules,supramolecular inclusion,and inorganic *** specifically,the analytical explorations of these systems were discussed,from the perspective of the relationship between analytes and ***,the further developments of aqueous RTP analysis were also prospected.

关键词： Room-temperaturephosphorescence Luminescence Aqueous Assembly Analytical detection

Highly efficient photocatalytic Suzuki coupling reaction by Pd_(3)P/CdS catalyst under visible-light irradiation

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Chinese Chemical Letters 2021年第2期32卷 676-680页

作者： Huai-Qing Yang qian-qian chen Fulai Liu Rui Shi Yong chen Key Laboratory of Photochemical Conversion and Optoelecctronic MaterialsεCAS-HKU Joint Laboratory on New Materials Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Monodispersed palladium phosphide(Pd_(3)P)(5.2 ± 0.5 nm) was firstly applied to photocatalytic Suzuki coupling reaction under visible light irradiation with CdS nanoflake as a photo *** heterogeneous system exhibited... 详细信息

关键词： Pd_(3)P CdS Photocatalysis Suzuki coupling reaction

Deep-learning-enabled dual-frequency composite fringe projection profilometry for single-shot absolute 3D shape measurement

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Opto-Electronic Advances 2022年第5期5卷 33-48页

作者： Yixuan Li Jiaming qian Shijie Feng qian chen Chao Zuo Smart Computational Imaging(SCI)Laboratory Nanjing University of Science and TechnologyNanjing 210094China Jiangsu Key Laboratory of Spectral Imaging&Intelligent Sense Nanjing University of Science and TechnologyNanjing 210094China

Single-shot high-speed 3D imaging is important for reconstructions of dynamic *** fringe projection profilometry(FPP),however,it is still challenging to recover accurate 3D shapes of isolated objects by a single fringe *** this paper,we demonstrate that the deep neural networks can be trained to directly recover the absolute phase from a unique fringe image that involves spatially multiplexed fringe patterns of different *** extracted phase is free from spectrum-aliasing problem which is hard to avoid for traditional spatial-multiplexing *** on both static and dynamic scenes show that the proposed approach is robust to object motion and can obtain high-quality 3D reconstructions of isolated objects within a single fringe image.

关键词： fringe projection profilometry(FPP) phase unwrapping deep learning

Differential privacy histogram publishing method based on dynamic sliding window

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Frontiers of Computer Science 2023年第4期17卷 209-220页

作者： qian chen Zhiwei NI Xuhui ZHU Pingfan XIA School of Management Hefei University of TechnologyHefei 230009China Key Laboratory of Process Optimization and Intelligent Decision-making Ministry of EducationHefei 230009China

Differential privacy has recently become a widely recognized strict privacy protection model of data *** privacy histogram publishing can directly show the statistical data distribution under the premise of ensuring user privacy for data query,sharing,and *** dynamic data release is a study with a wide range of current industry ***,the amount of data varies considerably over different *** data processing will result in the risk of users’information leakage and unavailability of the ***,we designed a differential privacy histogram publishing method based on the dynamic sliding window of LSTM(DPHP-DL),which can improve data availability on the premise of guaranteeing data ***-DL is integrated by DSW-LSTM and DPHK+.DSW-LSTM updates the size of sliding windows based on data value prediction via long shortterm memory(LSTM)networks,which evenly divides the data stream into several ***+heuristically publishes non-isometric histograms based on k-mean++clustering of automatically obtaining the optimal K,so as to achieve differential privacy histogram publishing of dynamic *** experiments on real-world dynamic datasets demonstrate the superior performance of the DPHP-DL.

关键词： differential privacy dynamic data histogram publishing sliding window

A high-safety active/passive hybrid control approach for compressor surge based on nonlinear model predictive control

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Chinese Journal of Aeronautics 2023年第1期36卷 396-412页

作者： Hanlin SHENG qian chen Jie ZHANG Tianhong ZHANG Jiangsu Province Key Laboratory of Aerospace Power System College of Energy and Power EngineeringNanjing University of Aeronautics and AstronauticsNanjing 210016China

Surge active control can expand the stable operating range of the ***,the difficulty of flow measurement,dynamic uncertainty disturbance,actuator delay characteristics,hard constraints of control variable,and system security measures have not been fully considered in the existing active control system,which significantly hinders its engineering ***,a nonlinear model predictive surge active control method is first presented based on flow estimator designed by using a continuous-time Kalman filter for dealing with the hard constraint of control variable and the impact of actuator delay of compression system with dynamic ***,a high-safety active/surge passive hybrid control strategy is designed,dominated by the surge active control and supplemented by the surge passive control,to ensure the compression system’s safe and stable ***,the simulation results suggest that the flow estimator accurately estimates the compressor *** considering the delay impact of the actuators and sensors and measurement noise on the system,the proposed method exhibits stronger robustness than the existing *** active/surge passive hybrid control strategy can successfully ensure the compression system’s safe and stable *** paper is of high practical significance for the engineering application of future compressor surge active control technologies.

关键词： Active control Compressor surge Flow estimator Hybrid system Model predictive control

Distributed Intelligent Reflecting Surfaces-Aided Device-to-Device Communications System

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Journal of Communications and Information Networks 2021年第3期6卷 197-207页

作者： Chiya Zhang Wenyu chen qian chen Chunlong He School of Electronic and Information Engineering Harbin Institute of TechnologyShenzhen 518055China Peng cheng Laboratory(PCL) Shenzhen 5180523China Guangdong Key Laboratory of Intelligent Information Processing Shenzhen UniversityShenzhen 518060China National Mobile Communications Research Laboratory Southeast UniversityNanjing 211189China

Intelligent reflecting surface(IRS)is a revolutionizing and promising technology to improve the high transmission rate of the wireless communication ***,an IRS consists of a great amount of low-cost passive reflecting elements,which reflect the incident signals to the desired user by collaboratively using passive *** paper introduces IRSs into a device-to-device(D2D)underlying cellular system to enhance transmission rate performance of the D2D *** formulate an optimization problem of maximizing the transmission rate of the D2D pairs while satisfying the minimum required rate of the cellular *** address this problem by jointly optimizing the reuse indicator,received beamforming,power allocation,and phase shift *** coordinate descent(BCD)algorithm is adopted to decouple the original problem into four *** form solutions are obtained by solving the sub-problems of optimizing the received beamforming and power ***,Kuhn-Munkres(KM)algorithm and minimization-majorization(MM)algorithm are adopted to solve the sub-problems of optimizing the reuse indicator and phase shift matrices,*** results demonstrate that IRSs can effectively improve the transmission rate of the D2D pairs and our proposed distributed IRSs scheme outperforms the other benchmark schemes.

关键词： intelligent reflecting surface device-to-device communications block coordinate descent

A chemometric analysis on the fluorescent dissolved organic matter in a full-scale sequencing batch reactor for municipal wastewater treatment

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Frontiers of Environmental Science & Engineering 2017年第4期11卷 179-186页

作者： chen qian Wei chen Wei-Hua Li Han-Qing Yu CAS Key Laboratory of Urban Pollutant Conversion Department of Chemistry University of Science and Technology of China Hefei 230026 China School of Environmental & Energy Engineering Anhui Jianzhu University Hefei 230026 China

Rapid monitoring of water quality is crucial to the operation of municipal wastewater treatment plants （WWTPs）. Fluorescence excitation-emission matrix （EEM） in combination with parallel lhctor analysis （PARAFAC） has been used as a powerful tool for the characterization of dissolved organic matter （DOM） in WWTPs. However, a recent work has revealed the drawback of PARAFAC analysis, i.e., overestimating the component number. A novel method, parallel lhctor framework-clustering analysis （PFFCA）,＂has been cleveloped in our earlier work to resolve this drawback of PARAFAC. In the present work, both PARAFAC and PFFCA were used to analyze the EEMs of water samples from a full-scale WWTP from a practical application point of view. The component number and goodness-of- fit from these two methods were compared and the relationship between the relative score change of component and the actual concentration was investigated to evaluate the estimation error introduced by 9 both methods. PFFCA score and actual concentration exhibited a higher correlation coefficient （R- = 0.870） compared with PARAFAC （R2〈 0.771）, indicating that PFFCA provided a more accurate relative change estimation than PARAFAC. The results suggest that use of PARAFAC may cause confusion in selecting the component number, while EEM-PFFCA is a more reliable alternative approach for monitoring water quality in WWTPs.

关键词： Wastewater treatment plants (WWTPs) Excitation-emission matrix (EEM) Parallel factor (PARAFAC) Parallel factor framework-clustering analysis (PFFCA)

Novel high-safety aeroengine performance predictive control method based on adaptive tracking weight

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Chinese Journal of Aeronautics 2024年第7期37卷 352-374页

作者： qian chen Hanlin SHENG Jie ZHANG Jiacheng LI College of Energy and Power Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China College of Automation Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

Increasing attention has been attracted to the dynamic performance and safety of advanced performance predictive control systems of the next-generation *** latest research demonstrates that Subspace-based Improved Model Predictive Control(SIMPC)can overcome the difficulty in solving the predictive model in MPC/NMPC ***,applying constant design parameters cannot maintain consistent control effects in all ***,the designed system relies too much on sensor-measured data,and thus it is difficult to thoroughly validate the safety of the system because of its high *** means that any potential hardware/software faults will endanger the ***,this paper first presents a novel nonlinear mapping relationship to adaptively tune the tracking weight online with the change of Power Lever Angle(PLA)and real-time relative tracking ***,without introducing additional design parameters,an Adaptive Tracking Weight-based SIMPC(ATW-SIMPC)controller is designed to improve the control performance in all operating states ***,a Primary/Backup Hybrid Control(PBHC)strategy with the ATW-SIMPC controller as the primary system and the traditional speed(Nf)controller as the backup system is proposed to ensure *** designed affiliated switching controller and the real-time monitor therein can be used to realize reasonable and smooth switching between primary/backup systems,so as to avoid bump *** PBHC system switches to the Nf controller when the ATW-SIMPC controller is wrong because of potential hardware/software faults;otherwise,the ATW-SIMPC controller keeps acting on the *** main results prove that the ATW-SIMPC controller with the optimal nonlinear mapping relationship,compared with the existing SIMPC controller,uplifts the dynamic control performance by 32%and reduces overshoots to an allowable limit,resulting in a better control effect in full *** comparison results consistently i

关键词： Aeroengine Model predictive control Hybrid system Adaptive weight Safety