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N-heterocyclic carbene-catalyzed atroposelective synthesis of axially chiral 5-aryl 2-pyrones from enals

Science China Chemistry 2022年第10期65卷 1953-1961页

作者： Guanjie Wang Juhui Huang Linxue Zhang Jinna Han Xiaoxiang Zhang Jie Huang Zhenqian Fu Wei Huang Key Laboratory of Flexible Electronics&Institute of Advanced Materials Institute of Advanced SynthesisSchool of Chemistry and Molecular EngineeringNanjing Tech UniversityNanjing 211816China Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources College of Chemical EngineeringNanjing Forestry UniversityNanjing 210037China Ningbo Institute Chongqing Technology innovation CenterFrontiers Science Center for Flexible Electronics(FSCFE)Northwestern Polytechnical UniversityXi’an 710072China

Axially chiral molecules have been widely used in inorganic,material and medicinal *** with well-established N-heterocyclic carbene(NHC)-catalyzed asymmetric construction of centrally chiral molecules,NHC-catalyzed atroposelective synthesis of axially chiral molecules remains largely ***,alkynyl acyl azolium intermediates were commonly used in constructing a heteroaryl ring to furnish axially enantioenriched *** inherent character of the intermediates often led to react with sterically hindered substrates ***,we have successfully disclosed the atroposelective synthesis of axially chiral heteroaryl-aryls from sterically hindered enols through the use of chiral NHCs as catalysts for highly enantioselective Coates-Claisen rearrangements via catalytically generatedα,β-unsaturated acyl *** approach will enable the concise synthesis of valuable tetra-ortho-substituted 2-pyrones in one step with good yield and chirality control.

关键词： N-heterocyclic carbene organocatalysis atroposelective synthesis 2-pyrones enals

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High-Performance Green Quasi-2D Perovskite Light-Emitting Diodes via Passivated Defects

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advanced Optical Materials 2024年第13期12卷

作者： Yang, Wei Ban, Xin-Xin He, Xiao-Li Huang, Xin-Mei Wang, Xiao-Yu Zhang, Yong Gao, Chun-Hong School of Physics and Materials Science Guangzhou University Guangzhou510006 China School of Physical Science and Technology MOE key laboratory on Luminescence and Real-Time Analysis Southwest University Chongqing400715 China School of Environmental and Chemical Engineering Jiangsu Key Laboratory of Function Control Technology for Advanced Materials Jiangsu Ocean University Jiangsu Lianyungang222005 China

In next generation semiconductors, metal halide perovskite materials would replace traditional light-emitting materials since their exceptional photoelectronic characteristics. The future development of perovskite light-emitting diodes have generated challenges such as abundant surface or interfacial defects and exciton quenching. To overcome these challenges, the light-emitting layer is modified utilizing benzimidazole/phosphine oxide hybrid 1,3,5-tris(1-(4-(diphenylphenylphosphoryl)phenyl)-1H-benzo[d]imidazol-2-yl)benzene (TPOB) and 1,3,5-tris(diphenylphosphoryl)benzene (TPO) with high triple energy state. It is demonstrated by X-ray photoelectron spectroscopy results that the oxygen atoms in the P = O functional group of TPOB and TPO provided lone electron pairs coordinate to the unsaturated Pb2+ in turn led to a decrease in the electron cloud density of Pb2+ and Br-, which can suppress defects. Additionally, this technique improved the morphology of film, reduced surface roughness, and facilitated carrier transport, all of which are crucial for achieving high-emission efficiency. As a result, the optimal devices has EQEs of 16.20 (TPOB) and 20.48% (TPO), respectively. Furthermore, the devices demonstrated excellent reproducibility. Excitingly, the champion EQE value for the optimal device is 22.64%. Simultaneously, it can increase the stability of the devices and the lifetimes are increased from 1231 s (Pristine) to 5421 (TPOB) and 5631 s (TPO). © 2024 Wiley-VCH GmbH.

关键词： Metal halides

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IEEE Transactions on Consumer Electronics 2025年

作者： Jiang, Zheng Zhou, Zhou Zhou, Quan Guo, Yongan Yang, Jing Ou, Weihua Nanjing University of Posts and Telecommunications Jiangsu Key Laboratory of Intelligent Information Processing and Communication Technology Nanjing China Nantong China Chinese Academy of Sciences State Key Laboratory of Robotics Shenyang Institute of Automation Shenyang China Guizhou University State Key Laboratory of Public Big Data Guiyang China Guizhou Normal University School of Big Data and Computer Science Guiyang China

Contrastive loss and its variants are very popular for visual representation learning in an unsupervised scenario, where positive and negative pairs are produced to train a feature encoder based on data augmentation. However, treating only the original image and its augmented versions as positive pairs may lead to problems, since two training images that share the same object category may be misclassified as negative pairs. To address this issue, this paper introduces a plug-in-play affinity similarity module (ASM) used in any contrastive learning framework for unsupervised visual representation learning. In this approach, positive and negative pairs are determined not only based on data augmentation, but also according to the similarity of their feature embeddings. The core idea is that two training samples with higher feature similarities are likely to belong to the same object category, suggesting that they should be classified as a positive pair with high probability, and vice versa for negative pairs. Accordingly, we have also developed an improved affinity similarity-based contrastive loss (ASCL) that leverages the newly generated positive and negative training pairs produced by the ASM. To demonstrate the effectiveness of our method, we extensively evaluate its performance on the ImageNet dataset, showing that it achieves satisfactory results. © 1975-2011 IEEE.

关键词： Unsupervised learning

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Variable admittance compliance control of upper limb training and rehabilitation robot based on genetic algorithm optimization 25

Variable admittance compliance control of upper limb trainin...

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Proceedings of the 2025 International Conference on Health Big Data

作者： Changjian Zhu Youwei Zhang Jialu Zhou Zenghai Shan School of Mechanical Engineering Nanjing Institute of Technology Nanjing Jiangsu China Graduate Workstation of Nanjing Kangni Mechanical & Electrical Co. Ltd Nanjing Jiangsu China State Key Laboratory of Intelligent Manufacturing of Advanced Construction Machinery Xuzhou Jiangsu China

ISBN: (纸本)9798400713446

The insufficient motion compliance of rope-driven rehabilitation robots during rehabilitation training, combined with the inability of widely used admittance control techniques in robotics to adapt to real-time compliance adjustments for rope-driven rehabilitation robots, presents a challenge. Moreover, traditional variable admittance control exhibits poor adaptability when faced with the individual differences of different patients, making it difficult to dynamically adjust control parameters based on the patient's real-time status and needs, leading to suboptimal rehabilitation outcomes. Therefore, this article takes the independently developed rope traction upper limb rehabilitation robot as the research object, and adopts a combination of genetic algorithm (GA), fuzzy controller, and admittance control to improve training effectiveness and safety. A new rehabilitation training equipment variable admittance control strategy is proposed to meet both clinical rehabilitation and daily training needs. This strategy utilizes genetic algorithm to optimize the parameters of the fuzzy controller, so that the output of the fuzzy controller can meet the real-time adjustment of admittance characteristics according to the patient's motion state, achieving precise control of force and motion, as well as autonomous adjustment of the flexibility of the rehabilitation robot. Simulation and experimental results show that the fuzzy control variable admittance model optimized based on genetic algorithm improves the accuracy by about 3.178% compared with the traditional admittance model, and at the same time, the system can still maintain good stability under load changes. During the patient's training process, the variable admittance control model optimized by the genetic algorithm demonstrated significant performance improvements in the upper limb rehabilitation robot system. This model enables the system to reach a stable state in a shorter time while maintaining smooth and accur

关键词： Admittance control

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Simultaneous enhancement of tensile strength and electrical conductivity of drawn Cu–20 wt.% Fe wire through intermediate annealing

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Journal of Iron and Steel Research International 2025年 1-16页

作者： Yang, Fei Wu, Can-Hui Wang, Yuan-Fang Li, Rui-Feng Shi, Feng-Jian Huo, Wen-Yi Dong, Li-Ming Zhou, Jun Qiao, Yan-Xin Fang, Feng School of Materials Science and Engineering Jiangsu University of Science and Technology Jiangsu Zhenjiang 212000 China Jiangsu Key Laboratory of Advanced Metallic Materials Southeast University Jiangsu Nanjing 211189 China Oil Production Technology Research Institute Liaoning Panjin 124000 China College of Mechanical and Electrical Engineering Nanjing Forestry University Jiangsu Nanjing 210037 China NOMATEN Centre of Excellence National Centre for Nuclear Research Mazowsze Otwock 05-400 Poland School of Automotive Engineering Changshu Institute of Technology Jiangsu Changshu 215500 China

The deformation of Cu–20 wt.% Fe alloy wires leads to a significant improvement in mechanical properties and a decrease in electrical conductivity. Simultaneous improvements in strength and conductivity were achieved by intermediate annealing of drawn Cu–20 wt.% Fe wires. As the annealing temperature increased, the strength of Cu–20 wt.% Fe alloy wire decreased monotonically, but the electrical conductivity first increased and then decreased, reaching its peak value after annealing at 500 °C. The decrease in strength is related to dislocation recovery and static recrystallization of Cu and Fe phases, and the increase in electrical conductivity mainly results from the aging precipitation of solid solution Fe. After annealing at 500 °C, there was no obvious recrystallization of Cu phase, and many of the nano-Fe particles precipitated from Cu matrix. An annealing temperature of 600 °C induced the recrystallization of Cu matrix and an increase in Fe solid solubility, resulting in a decrease in strength and electrical conductivity. Subsequently, the wires annealed at 500 °C were drawn to 2 mm. Compared with those of the continuously drawn Cu–20 wt.% Fe alloy wires, the deformation ability, strength, and electrical conductivity of Cu–20 wt.% Fe alloy wires subjected to intermediate annealing treatment are significantly greater. This is mainly related to the sufficient precipitation of Fe in Cu matrix and the strengthening of refined Fe fibers parallel to the drawing direction. © China Iron and Steel Research Institute Group Co., Ltd. 2025.

关键词： Cu–Fe alloy wire Drawing deformation Electrical conductivity Intermediate annealing Mechanical property

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Super Stable Selenium Nickel-Iron Electrocatalyst for Oxygen Evolution Reaction in Natural Seawater

SSRN

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SSRN 2024年

作者： Wang, Jue Li, Zhi Feng, Libei Lu, Dachun Fang, LiWei Zhang, Qinfang Hedman, Daniel Tong, Shengfu Key Laboratory for Advanced Technology in Environmental Protection of Jiangsu Province School of Materials Science and Engineering Yancheng Institute of Technology Jiangsu Yancheng224051 China Ulsan44919 Korea Republic of Department of Sustainable Energy Materials and Sciences Jinhua Advanced Research Institute Zhejiang Jinhua321013 China

Efficient and stable catalysts for oxygen evolution reaction (OER) in seawater presents a major challenge for hydrogen production through water electrolysis. In this work, we present an ultra-stable NiFe foam catalyst with a Se-doped Ni/Fe oxide surface prepared through a combination of chemical vapor deposition and electrochemical exfoliation. This method effectively modifies the surface of the commercial NiFe foam to a rough and stable Se-doped Ni/Fe oxide surface, displaying exceptional OER performance in both freshwater and seawater with more than 54 days stability. Experimental characterization and density functional theory calculations reveal that high concentration of NiSe on the surface, with subsurface layers consisting of Ni alloyed with a moderate concentration of Fe, optimizes the adsorption free energy of oxygen-containing intermediates. Our results demonstrate a surface engineering approach to activate NiFe foam as a robust OER catalyst for seawater electrolysis, which is beneficial for the hydrogen economy and for the environment. © 2024, The Authors. All rights reserved.

关键词： Chemical vapor deposition

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Intra-Vehicle Optical Networks

Intra-Vehicle Optical Networks

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International Conference on Optical Communications and Networks (ICOCN)

作者： Qin Liang Gordon Ning Liu School of Electronic and Information Engineering Soochow University Suzhou Jiangsu China Suzhou Key Laboratory of Advanced Optical Communication Network Technology Soochow University Suzhou China

Intelligent connected vehicles require high bandwidth due to the increased sensors and improved architectures. Optical communications provide several advantages over copper cables in intra-vehicle networks, but face m... 详细信息

ISBN: (数字)9798350367652

ISBN: (纸本)9798350367669

关键词： Temperature sensors Temperature distribution Connected vehicles Bandwidth Optical fiber networks Downlink Reliability engineering

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Development of Phase-Field Modeling in Materials Science in China:A Review

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Acta Metallurgica Sinica(English Letters) 2023年第11期36卷 1749-1775页

作者： Yuhong Zhao Hui Xing Lijun Zhang Houbing Huang Dongke Sun Xianglei Dong Yongxing Shen Jincheng Wang Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing100083China MOE Key Laboratory of Material Physics and Chemistry Under Extraordinary Shaanxi Basic Discipline(Liquid Physics)Research CenterNorthwestern Polytechnical UniversityXi’an710129China State Key Laboratory of Powder Metallurgy Central South UniversityChangsha410083China School of Materials Science and Engineering Beijing Institute of TechnologyBeijing100081China Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments School of Mechanical EngineeringSoutheast UniversityNanjing211189China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou450001China University of Michigan-Shanghai Jiao Tong University Joint Institute Shanghai Jiao Tong UniversityShanghai200240China State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an710072China School of Materials Science and Engineering Collaborative Innovation Center of Ministry of Education and Shanxi Province for High-Performance Al/Mg Alloy MaterialsNorth University of ChinaTaiyuan030051China Institute of Materials Intelligent Technology Liaoning Academy of MaterialsShenyang110004China

Phase-field method,as a powerful and popular approach to predict the mesoscale microstructure evolution in various materials science,provides a bridge from atomic-scale methods to the macroscale and has been widely used at an ever-increasing *** paper aims to briefly review the origin,basic idea,and development of phase-field models in a historical *** focus is placed on the classical and state-of-the-art applications in China,including liquid–solid,solid–solid,gas–solid,ferroelectrics/ferromagnetics phase transformation,and crack *** introducing the academic activities in the phase-field community in China,some suggestions for the future development directions of phase-field method are finally mentioned.

关键词： Phase-field method Microstructure Phase transformation Various materials design

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The Optimum Conditions of Loose Particles Detection for Microelectronic Packaging

The Optimum Conditions of Loose Particles Detection for Micr...

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Electronics Packaging technology Conference (EPTC)

作者： Xinfang Duan Lei Su Ke Li Jiefei Gu Xinwei Zhao Michael Pecht Jiangsu Key Laboratory of Advanced Food Manufacturing Equipment and Technology School of Mechanical Engineering Jiangnan University Wuxi China Center for Advanced Life Cycle Engineering University of Maryland College Park MD USA

ISBN: (数字)9798331522001

ISBN: (纸本)9798331522018

To achieve effective detection of loose particles within small cavities in microelectronic devices, this paper proposes the optimal detection conditions of loose particles in ceramic packaging for microelectronic devices based on simulation. Through establishing a particle-cavity collision dynamics model in ADAMS, the motion process of particles under sinusoidal excitation is simulated. Subsequently, the paper examines the impact of different accelerations, frequencies, loose particles' properties, and cavity heights on optimal detection conditions. Furthermore, the paper presents the optimal conditions for vibration testing, providing a valuable reference for the effective detection of loose particles in hermetically sealed microelectronic devices.

关键词： Vibrations Analytical models Noise Dynamics Life estimation Packaging Microelectronics Ceramics Testing Electronics packaging

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Three-Dimensional Plant Pivotal Organs Photogrammetry on Cherry Tomatoes Using an Instance Segmentation Method and a Spatial Constraint Search Strategy

SSRN

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SSRN 2023年

作者： Rong, Jiacheng Yang, Yan Zheng, Xiajun Wang, Song Yuan, Ting Wang, Pengbo College of Engineering China Agricultural University Beijing100083 China School of Mechanical and Electric Engineering Jiangsu Provincial Key Laboratory of Advanced Robotics Soochow University Suzhou215123 China

Phenotypic analysis of tomato crops is crucial for automated crop management since it provides robots with fundamental perceptual capabilities necessary for advanced tasks such as 3D reconstruction and precise harvesting localization. However, the heterogeneous growth posture of tomato clusters and tiny pedicel characteristics present challenges in accurately capturing critical tomato organs. This work introduces a visual methodology that efficiently processes point clouds of tomato organs, including instance segmentation-based tomato organ segmentation and a point cloud constrained-search strategy for tomato organ matching. The segmentation of plant organs involves two stages. Firstly, YOLOv5-4D is utilized to detect the region of interest (ROI) on tomatoes. Then, the improved SOLOv2 instance segmentation algorithm integrating with Coordinate Attention is developed to enhance the segmentation performance of tiny pedicels. In the test dataset, YOLOv5-4D achieves an mAP of 0.953 at a speed of 78.1 FPS, while the enhanced SOLOv2 delivers a performance of 20.8 FPS with an mAP of 0.742. Furthermore, a point cloud constraint-based search method is proposed to address the issue of matching tomato organs in 3D space. Initially, some point cloud filters are used to remove outliers, and then the constraint conditions of fruit-bearing stems and pedicels are designed based on the biological characteristics of the tomato. Finally, a point cloud search method is designed to optimize the matching between fruits and other fruit-bearing organs. In the on-site experiments, the proposed visual pipeline was used to match tomatoes in 150 different scenarios, achieving a success rate of 86.7%. The results demonstrate that the developed methodology is effective in accurately identifying and matching tomato plants in various real-world scenarios. © 2023, The Authors. All rights reserved.

关键词： Fruits

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