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NHC-mediated photocatalytic para-selective C–H acylation of aryl alcohols: regioselectivity control via remote radical spiro cyclization

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Science China Chemistry 2025年

作者： Tinglei zhang Lala Wang Xiaolin Peng Tianhui Liao Dongmei Chen Ting Tu Donghan Liu Ziye Cheng Shiqing Huang Shi-Chao Ren xinglong zhang Yonggui Robin Chi State Key Laboratory of Green Pesticide Key Laboratory of Green Pesticide and Agricultural Bioengineering Ministry of Education Guizhou University Qiannan Medical College for Nationalities School of Chemistry Chemical Engineering and Biotechnology Nanyang Technological University Department of Chemistry The Chinese University of Hong Kong Institute of High Performance Computing Agency for Science Technology and Research

Friedel-Crafts reaction and transition-metal catalysis represent primary methodologies for arene acylation; however, suffer from certain limitations, such as electronic effect-dependent reactivity, regioselectivity issues, the necessity of directing group, and relatively exceptionally limited exploration in meta-and para-acylations. N-heterocyclic carbene(NHC) catalysis has recently emerged as a promising alternative strategy for arene acylation, offering distinct regioselectivity profiles that are challenging to achieve through known methods. Herein, an NHC-mediated photo-catalytic para-selective C–H acylation of aryl alcohols is disclosed. The reaction employs a remote radical-induced temporary spiro cyclization strategy, proceeding via tandem radical dearomatization, radical acylation, rearomatization processes. Combined experimental and computational mechanistic studies support the proposed reaction pathway and observe an exclusive para-selectivity regardless of the nature of the substituents on the substrates. Despite the less satisfactory yields, the current method exhibits non-electronic nature-based reactivity and regioselectivity, enabling quick access to acylated arenes that are difficult or impossible for reported methods.

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LaTLS: A Lattice-Based TLS Proxy Protocol

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Chinese Journal of Electronics 2022年第2期31卷 313-321页

作者： zhang xinglong CHENG Qingfeng LI Yuting State Key Laboratory of Mathematical Engineering and Advanced Computing

The function of the Internet proxy is to check and convert the data exchanged between client and server. In fact, the two-party secure communication protocol with good security is turned into an unsafe multiparty protocol. At present, there are relatively few proxy protocols that can be applied in practice. This paper analyzes the classic agent protocol mcTLS and pointed out the security issues. We focus on the security of TLS 1.3 and proposed a lattice-based multi-party proxy protocol:La TLS. LaTLS can be proved secure in the eCK model, it can resist key-sharing attacks, counterfeiting attacks, replay attacks, and achieve forward security. Compared with traditional DH and ECDH schemes, LaTLS is more effcient. Its security is based on the shortest vector problem, therefor it has anti-quantum attack properties.

关键词： security issues Internet lattice-based multiparty proxy protocol relatively few proxy protocols data exchanged LaTLS key sharing attacks unsafe multiparty protocol Internet proxy shortest vector problem protocols antiquantum attack properties forward security two-party secure communication protocol classic agent protocol mcTLS classic agent protocol computer network security

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Deep reinforcement learning based active surge control for aeroengine compressors

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Chinese Journal of Aeronautics 2024年第7期37卷 418-438页

作者： xinglong zhang Zhonglin LIN Runmin JI Tianhong zhang College of Energy and Power Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China School of Mechanical Engineering and Automation Fuzhou UniversityFuzhou 350108China

This study proposes an active surge control method based on deep reinforcement learning to ensure the stability of compressors when adhering to the pressure rise command across the wide operating range of an ***,the study establishes the compressor dynamic model with uncertainties,disturbances,and Close-Coupled Valve(CCV)actuator *** upon this foundation,a Partially Observable Markov Decision Process(POMDP)is defined to facilitate active surge *** address the issue of unobservability,a nonlinear state observer is designed using a finite-time high-order sliding ***,an Improved Soft Actor-Critic(ISAC)algorithm is developed,incorporating prioritized experience replay and adaptive temperature parameter techniques,to strike a balance between exploration and convergence during *** addition,reasonable observation variables,error-segmented reward functions,and random initialization of model parameters are employed to enhance the robustness and generalization ***,to assess the effectiveness of the proposed method,numerical simulations are conducted,and it is compared with the fuzzy adaptive backstepping method and Second-Order Sliding Mode Control(SOSMC)*** simulation results demonstrate that the deep reinforcement learning based controller outperforms other methods in both tracking accuracy and ***,the proposed active surge controller can effectively ensure stable operation of compressors in the high-pressure-ratio and high-efficiency region.

关键词： Aeroengine surge Active surge control Moore-Greitzer model Deep reinforcement learning Soft actor-critic Nonlinear observer

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Pneumatic pressure control based on improved NMPC and its application to aeroengine surge simulation

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Chinese Journal of Aeronautics 2023年第4期36卷 468-485页

作者： xinglong zhang Zhonglin LIN Jiaao LI Tianhong zhang College of Energy and Power Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China School of Mechanical Engineering and Automation Fuzhou UniversityFuzhou 350108China

In the semi-physical simulation of aeroengines,using the pneumatic pressure servo control technology to provide realistic pneumatic excitation to the sensors and electronic controller can improve the confidence of the simulation and reduce the test cost and ***,the existing methods could not satisfy the precise simulation of large-amplitude and high-frequency pulsating pressure during aeroengine *** this paper,a pneumatic pressure control system with asymmetric groups of the High-Speed on–off Valve(HSV)is designed,and an Improved Nonlinear Model Predictive Control(INMPC)method is ***,the volumetric flow characteristics of HSV are tested and analyzed with Pulse Width Modulation(PWM)signal ***,a simplified HSV model with the volume flow characteristic correction is *** on these,an integrated model for the whole system is further established and used as the prediction model in *** improve the computational speed of the rolling optimization process,the mapping scheme from control signal to PWM duty cycle of HSVs and the objective function with exterior penalty function are ***,the random step,sinusoidal and real engine surge data are set as the reference pressure in multiple comparative experiments to verify the effectiveness of the pressure tracking system.

关键词： Aeroengine surge simulation Asymmetric valve groups High-speed on–off valve Nonlinear model predictive control Pneumatic pressure tracking control

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Event-triggered shared lateral control for safe-maneuver of intelligent vehicles

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Science China(Information Sciences) 2021年第7期64卷 48-65页

作者： Yan JIANG xinglong zhang Xin XU Xing ZHOU Zhengzheng DONG College of Intelligence Science and Technology National University of Defense Technology

With the increasing number of cars, road traffic accidents have caused a lot of losses every year and human factors play an important role in many cases. Applying active safety assistance control or shared control techniques in intelligent vehicles is promising to reduce the number of traffic accidents. In this context, the dynamic optimization of the shared control policy and the smooth transitions of control authority between human drivers and intelligent driving systems are critical issues to be solved. Motivated by this,this paper proposes an event-triggered shared control approach for safe-maneuver of intelligent vehicles with online risk assessment. In the proposed approach, a Bayesian regularized artificial neural network(BRANN)is designed to predict vehicle trajectories and build a quantization function to assess the risk level owing to potential collision events. The shared controller dynamically optimizes the shared control policies between the human and the intelligent driving system via solving a model predictive control(MPC) problem. The predicted driving behaviors in the prediction horizon are pre-computed with a finite-horizon model predictor steering the predicted trajectories contributed by human driving. Moreover, smooth transitions back to human driving mode are realized via adding penalties on the shared control of the intelligent driving *** simulation scenarios in the PreScan environment, i.e., rear-end collision avoidance, lane-keeping and unskilled driving, are studied to test the effectiveness of the proposed approach. The simulation results,including the comparison with a linear quadratic regulator(LQR)-based shared controller, are reported,which show that the proposed approach can timely evaluate dangerous events and realize safe driving in terms of collision avoidance and lane-keeping. Also, the proposed approach outperforms the LQR-based shared controller in terms of smooth transitions.

关键词： trajectory prediction risk assessment shared lateral control model predictive control

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A self-learning human-machine cooperative control method based on driver intention recognition

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CAAI Transactions on Intelligence Technology 2024年第5期9卷 1101-1115页

作者： Yan Jiang Yuyan Ding xinglong zhang Xin Xu Junwen Huang College of Intelligence Science and Technology National University of Defense TechnologyChangshaChina Department of Computer Science Technical University of MunichGarchingGermany

Human-machine cooperative control has become an important area of intelligent driving,where driver intention recognition and dynamic control authority allocation are key factors for improving the performance of cooperative decision-making and *** this paper,an online learning method is proposed for human-machine cooperative control,which introduces a priority control parameter in the reward function to achieve optimal allocation of control authority under different driver intentions and driving safety ***,a two-layer LSTM-based sequence prediction algorithm is proposed to recognise the driver's lane change(LC)intention for human-machine cooperative steering ***,an online reinforcement learning method is developed for optimising the steering authority to reduce driver workload and improve driving *** driver-in-the-loop simulation results show that our method can accurately predict the driver's LC intention in cooperative driving and effectively compensate for the driver's non-optimal driving *** experimental results on a real intelligent vehicle further demonstrate the online optimisation capability of the proposed RL-based control authority allocation algorithm and its effectiveness in improving driving safety.

关键词： Self-leaming Control Hmman-machine Cooperation Intelligent Vehicles Reinfocement Learning

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Unidirectionally aligned diphenylalanine nanotube/ microtube arrays with excellent supercapacitive performance

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Nano Research 2014年第6期7卷 929-937页

作者： Jinlei zhang xinglong Wu Zhixing Gan Xiaobin Zhu Yamin Jin National Laboratory of Solid State Microstructures and Department of Physics Nanjing University Nanjing 210093 China

High-temperature （150-220 ℃） growth leads to the formation of some peptide nanotube/microtube （NT/MT） arrays but the NTs/MTs exhibit closed ends, irreversible phase modification and eliminations of piezoelectric and hydrophilic properties. Here we demonstrate the fabrication of unidirectionally aligned and stable diphenylalanine NT/MT arrays with centimeter scale area at room temperature by utilizing an external electric field. The interactions between the applied electric field and dipolar electric field on the NTs and surface positive charges are responsible for the formation. The unidirectionally aligned MT array exhibits a supercapacitance of 1,000 μF·cm^-2 at a scanning rate of 50 mV·s^-1; this is much larger than the values reported previously in peptide NT/MT arrays.

关键词： FF nanotubes/microtubes aligned growth surface charge supercapacitance

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A deep Koopman operator-based modelling approach for long-term prediction of dynamics with pixel-level measurements

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CAAI Transactions on Intelligence Technology 2024年第1期9卷 178-196页

作者： Yongqian Xiao Zixin Tang Xin Xu xinglong zhang Yifei Shi College of Intelligence Science and Technology National University of Defense TechnologyChangshaChina

Although previous studies have made some clear leap in learning latent dynamics from high-dimensional representations,the performances in terms of accuracy and inference time of long-term model prediction still need to be *** this study,a deep convolutional network based on the Koopman operator(CKNet)is proposed to model non-linear systems with pixel-level measurements for long-term *** adopts an autoencoder network architecture,consisting of an encoder to generate latent states and a linear dynamical model(i.e.,the Koopman operator)which evolves in the latent state space spanned by the *** decoder is used to recover images from latent *** to a multi-step ahead prediction loss function,the system matrices for approximating the Koopman operator are trained synchronously with the autoencoder in a mini-batch *** this manner,gradients can be synchronously transmitted to both the system matrices and the autoencoder to help the encoder self-adaptively tune the latent state space in the training process,and the resulting model is time-invariant in the latent ***,the proposed CKNet has the advantages of less inference time and high accuracy for long-term *** are per-formed on OpenAI Gym and Mujoco environments,including two and four non-linear forced dynamical systems with continuous action *** experimental results show that CKNet has strong long-term prediction capabilities with sufficient precision.

关键词： deep neural networks image motion analysis image sequences sequential estimation

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Polo-like kinase 1 suppresses lung adenocarcinoma immunity throughnecroptosis

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Oncology Research 2023年第6期31卷 937-953页

作者： PENGCHENG zhang xinglong zhang YONGFU ZHU YIYI CUI JING XU WEIPING zhang Department of Oncology The Third Affiliated Hospital of Zhejiang Chinese Medical UniversityHangzhouChina Department of Oncology Anhui Zhongke Gengjiu HospitalHefeiChina Department of Oncology The First Affiliated Hospital of Anhui University of Chinese MedicineHefeiChina Department of Biochemistry and Molecular Biology School of Integrated Chinese and Western MedicineAnhui University of Chinese MedicineHefeiChina

Polo-like kinase 1(PLK1)plays a crucial role in cell mitosis and has been associated with ***,the role of PLK1 and necroptosis in lung adenocarcinoma(LA)remains *** this study,we analyzed The Cancer Genome Atlas(TCGA)and Genotype-Tissue Expression databases to evaluate the prognostic value and mechanistic role of PLK1 in ***1 was found to be highly expressed in LA and was positively associated with advanced disease staging and poor survival *** enrichment analysis showed that PLK1 was involved in cell mitosis,neurotransmitter transmission,and drug *** analysis using single-sample gene set enrichment analysis and ESTIMATE algorithm revealed a correlation between PLK1 expression and immune infiltration in *** of PLK1 using miRNA transfection in LA cells reduced cell proliferation and increased apoptosis,as well as upregulating the expression of necroptosis-related proteins,such as RIPK1,RIPK3,and ***,nude mouse transplantation tumor experiments demonstrated that silencing PLK1 reduced the growth capacity of LA *** findings suggest that PLK1 plays a critical role in LA progression by regulating necroptosis and immune infiltration,and may serve as a potential therapeutic target for ***,PLK1 expression can be used as a prognostic biomarker for LA patients.

关键词： PLK1 Lung adenocarcinoma Prognosis biomarker Immune infiltration Necroptosis

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Spatial compartmentalization of metal nanoparticles within metal-organic frameworks for tandem reaction

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Nano Research 2022年第2期15卷 1178-1182页

作者： Ting Pan Islam E.Khalil Zhiling Xu Hongfeng Li xinglong zhang Gengwu Xiao Weina zhang Yu Shen Fengwei Huo Key Laboratory of Flexible Electronics(KLOFE)and Institute of Advanced Materials(IAM) Nanjing Tech UniversityNanjing 211816China

Fabrication of multifunctional catalysts has always been the pursuit of synthetic chemists due to their efficiency,cost-effectiveness,and environmental ***,it is difficult to control multi-step reactions in one-pot,especially the spatial compartmentalization of incompatible active ***,we constructed metal-organic framework(MOF)composites which regulate the location distribution of metal nanoparticles according to the reaction path and coupled with the diffusion of substrates to achieve tandem *** designed UiO-66-Pt-Au catalyst showed good activity and selectivity in hydrosilylation-hydrogenation tandem reaction,because the uniform microporous structures can control the diffusion path of reactants and intermediates,and Pt and Au nanoparticles were arranged in core-shell spatial distribution in *** contrast,the low selectivity of catalysts with random deposition and physical mixture demonstrated the significance of artificial control to the spatial compartmentalization of active sites in tandem catalytic reactions,which provides a powerful approach for designing high-performance and multifunctional heterogeneous catalysts.

关键词： metal-organic frameworks metal nanoparticles spatial compartmentalization tandem reaction heterogeneous catalysis

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