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A Quadruply Bridged Non-Offset Face-to-Face Porphyrin Dimer and Cross-Shaped Pentameric Porphyrin Tapes Based on 2,7,12,17-Tetrakis(pinacolatoboryl) NiIIPorphyrin

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Angewandte Chemie 2023年第13期135卷

作者： Meng Ye Fangling Deng Dr. Ling Xu Dr. Yutao Rao Dr. Bangshao Yin Prof. Dr. Mingbo Zhou Ryo Kurosaki Prof. Dr. Naoki Aratani Prof. Dr. Atsuhiro Osuka Prof. Dr. Jianxin Song Key Laboratory of Chemical Biology and Traditional Chinese Medicine Ministry of Educational of China Key Laboratory of the Assembly and Application of Organic Functional Molecules of Hunan Province College of Chemistry and Chemical Engineering Hunan Normal University Changsha 410081 China Division of Materials Science Nara Institute of Science and Technology (NAIST) 8916-5 Takayama-cho Ikoma 630-0192 Japan

2,7,12,17-Tetrakis(pinacolatoboryl) Ni II porphyrin 5 Ni was synthesized in 75 % yield by Ir-catalyzed borylation of porphine followed by Ni II metalation and has been demonstrated to be a useful synthon, giving 2,7,12,17-tetraaryated Ni II porphyrins 6 a – d , peripherally octaarylated Ni II porphyrins 8 a – d , quadruply bridged face-to-face non-offset Ni II -porphyrin dimer 12 , and cross-shaped β-meso singly linked porphyrin pentamers and nonamers. Oxidation of cross-shaped β-meso singly linked porphyrin pentamers 14 Ni and 14 Zn gave fused pentameric tapes 15 Ni and 15 Zn . The structures of 12 , 14 Zn , and 15 Ni have been revealed by X-ray diffraction analysis. Optical separation of 12 has been accomplished, showing a bisignate coupling pattern for exciton-coupled blue-shifted Soret band. Pentameric porphyrin tape 15 Zn exhibits a red-shifted absorption band at 1156 nm and seven reversible redox waves.

关键词： Borylporphyrins Near-Infrared Absorption Non-Offset Dimer Porphyrins Synthons

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Chiral Phosphoric Acid Catalyzed Asymmetric Hydrolysis of Biaryl Oxazepines for the Synthesis of Axially Chiral Biaryl Amino Phenol Derivatives

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Angewandte Chemie 2023年第39期135卷

作者： Liwen Wei Jiaomeng Li Yi Zhao Qinglong Zhou Zhikang Wei Yuhang Chen Dr. Xinglong Zhang Prof. Dr. Xing Yang Key Laboratory of Chemical Biology and Traditional Chinese Medicine (Ministry of Educational of China) Key Laboratory of the Assembly and Application of Organic Functional Molecules of Hunan Province College of Chemistry and Chemical Engineering Hunan Normal University Changsha 410081 P. R. China Institute of High Performance Computing Agency for Science Technology and Research (A*STAR) Singapore 138632 Singapore

The development of catalytic asymmetric reaction with water as the reactant is challenging due to the reactivity- and stereoselectivity-control issues resulted from the low nucleophilicity and the small size of water. We disclose herein a chiral phosphoric acid (CPA) catalyzed atroposelective ring-opening reaction of biaryl oxazepines with water. A series of biaryl oxazepines undergo the CPA catalyzed asymmetric hydrolysis in a highly enantioselective manner. The key for the success of this reaction is the use of a new SPINOL-derived CPA catalyst and the high reactivity of biaryl oxazepine substrates towards water under acidic conditions. Density functional theory calculations suggest that the reaction proceeds via a dynamic kinetic resolution pathway and the CPA catalyzed addition of water to the imine group is both enantio- and rate-determining.

关键词： Atropisomerism Bridged Biaryls Hydrolysis Organocatalysis Ring-Opening

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Study on the Toxicity of Acetochlor to Loaches

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Agricultural Biotechnology 2020年第3期9卷 49-52,66页

作者： Yan WANG Peng DONG Pei XU Yuxiang LIN Zexin CHEN Yihong HU Chenzhong JIN Yiding WANG Kaifa GUO Qianxia ZHU Key Laboratory of Pesticide Hamless Application/Hunan Provincial Collaborative Innovation Center for Field Weeds Control Hunan University of HumanitiesScience and TechnologyLoudi 417000China Xinsheng Planting and Breeding Farmers Specialized Cooperative of Shuangfeng County Hunan ProvinceShuangfeng 417100China

[Objectives] This study was conducted to investigate the toxic effect of acetochlor in loaches. [Methods]Loaches were put into the acetochlor solution with concentrations of 0,0. 062 5,0. 125,0. 25,0. 5 and 1 μl/L,respectively. The effects on dismutase( SOD),peroxidase( POD),catalase( CAT) and glutathione( GSH) activity and malondialdehyde( MDA) content in the liver of loaches were analyzed after 12,24,48 and 72 h of exposure. [Results] The activity of SOD,POD,CAT and GSH increased with the stress time and concentration,reached their maximums at 48 h after acetochlor treatment,and then ***,MDA content increased with the stress time and concentration. [Conclusions] Acetochlor had obvious oxidative stress on loaches,and the activity of SOD,POD,CAT and GSH showed an obvious induction-inhibition effect with the increase of acetochlor concentration and the extension of stress time.

关键词： Acetochlor Loach Antioxidative enzyme system Malondialdehyde

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A joint call for actions to advance taxonomy in China

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Zoological Systematics 2022年第3期47卷 188-197页

作者： Chaodong Zhu Arong Luo Ming Bai Michael COrr Zhonge Hou Siqin Ge Jun Chen Yibo Hu Xuming Zhou Gexia Qiao Hongzhi Kong Limin Lu Xiaohua Jin Lei Cai Xinli Wei Ruilin Zhao Wei Miao Qingfeng Wang Zhongli Sha Qiang Lin Meng Qu Jianping Jiang Jiatang Li Jing Che Xuelong Jiang Xiaoyong Chen Lianming Gao Zongxin Ren Chunlei Xiang Shixiao Luo Donghui Wu Dong Liu Yanqiong Peng Tao Su Chenyang Cai Tianqi Zhu Wanzhi Cai Xingyue Liu Hu Li Huaijun Xue Zhen Ye Xuexin Chen Pu Tang Shujun Wei Hong Pang Qiang Xie Feng Zhang Feng Zhang Xianjin Peng Aibing Zhang Taiping Gao Changfa Zhou Chen Shao Libin Ma Zhaoming Wei Yunxia Luan Ziwei Yin Wu Dai Cong Wei Xiaolei Huang Jingxian Liu Xiangsheng Chen Tianci Yi Zhisheng Zhang Zhulidezi Aishan Qin Li Hongying Hu CAS Key Laboratory of Zoological Systematics and Evolution Institute of ZoologyChinese Academy of SciencesBeijing 100101China CAS Key Laboratory of Animal Ecology and Conservation Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China State Key Laboratory of Systematic and Evolutionary Botany Institute of BotanyChinese Academy of SciencesBeijing 100093China State Key Laboratory of Mycology(SKLM) Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China CAS Key Laboratory of Aquatic Biodiversity and Conservation Institute of HydrobiologyChinese Academy of SciencesWuhan 430072China Wuhan Botanical Garden Chinese Academy of SciencesWuhan 430074China Department of Marine Organism Taxonomy&Phylogeny Institute of OceanologyChinese Academy of SciencesQingdao 266071China CAS Key Laboratory of Tropical Marine Bio-resources and Ecology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization&Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province Chengdu Institute of BiologyChinese Academy of SciencesChengdu 610041China State Key Laboratory of Genetic Resources and Evolution&Yunnan Key Laboratory of Biodiversity and Ecological Security of Gaoligong Mountain Kunming Institute of ZoologyChinese Academy of SciencesKunming 650221China CAS Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China CAS Key Laboratory of Plant Resource Conservation and Sustainable Utilization South China Botanical GardenChinese Academy of SciencesGuangzhou 510650China CAS Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun 130102China CAS Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglunMenglaYunnan 66630

Taxonomy plays an important role in understanding the origin, evolution, and ecological functionality of biodiversity. There are large number of unknown species yet to be described by taxonomists, which together with their ecosystem services cannot be effectively protected prior to description. Despite this, taxonomy has been increasingly underrated insufficient funds and permanent positions to retain young talents. Further, the impact factordriven evaluation systems in China exacerbate this downward trend, so alternative evaluation metrics are urgently necessary. When the current generation of outstanding taxonomists retires,there will be too few remaining taxonomists left to train the next generation. In light of these challenges, all co-authors worked together on this paper to analyze the current situation of taxonomy and put out a joint call for immediate actions to advance taxonomy in China.

关键词： Endangered taxonomists morphology-based taxonomy integrative taxonomy capacity building systematics

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Signatures of linear Breit-Wheeler pair production in polarized γγ collisions

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Physical Review D 2022年第7期105卷 L071902-L071902页

作者： Qian Zhao Liang Tang Feng Wan Bo-Chao Liu Ruo-Yu Liu Rui-Zhi Yang Jin-Qing Yu Xue-Guang Ren Zhong-Feng Xu Yong-Tao Zhao Yong-Sheng Huang Jian-Xing Li Ministry of Education Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter Shaanxi Province Key Laboratory of Quantum Information and Quantum Optoelectronic Devices School of Physics Xi’an Jiaotong University Xi’an 710049 China College of Physics and Hebei Key Laboratory of Photophysics Research and Application Hebei Normal University Shijiazhuang 050024 China School of Astronomy and Space Science Nanjing University 210023 Nanjing Jiangsu China CAS Key Labrotory for Research in Galaxies and Cosmology Department of Astronomy School of Physical Sciences University of Science and Technology of China Hefei Anhui 230026 China School of Physics and Electronics Hunan University Changsha 410082 China School of Science Shenzhen Campus of Sun Yat-sen University Shenzhen 518107 China Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China

The polarization characteristics of the linear Breit-Wheeler (LBW) pair-production process in polarized γγ colliders have been investigated via our developed spin-resolved binary collision simulation method. We find that the polarization of γ-photons modifies the kinematics of scattering particles and induces the correlated energy-angle shift of LBW pairs, and the latter’s polarization characteristic depends on the helicity configures of scattering particles. We confirm that the polarized γγ collider with an asymmetric setup can be performed with currently achievable laser-driven high-density x rays and high-brilliance γ-photon beams to produce abundant polarized LBW pairs, fulfilling the detection power of polarimetries. Our method and results on the polarized LBW process have plenty of significant applications in strong-field physics, high-energy physics and astrophysics, such as calibrating and monitoring the polarized γγ collider and challenging the current understanding of astrophysical objects through enhancing the opacity of γ-photons to exacerbate the inconsistency between some observations and standard models.

关键词： Beam code development & simulation techniques Beam polarization Beam processes Gamma-ray generation in plasmas Relativistic multiple-particle dynamics Secondary beams Monte Carlo methods Quantum Monte Carlo

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Lightning Trip Warning Based on GA-BP Neural Network technology

Lightning Trip Warning Based on GA-BP Neural Network Technol...

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HVDC (HVDC), International Conference on

作者： Gu Su Tang Chongwang Deng Zhiyong Wang Zhenyu Wang Jia Feng Yongkun State Grid Hunan Power Transmission Maintenance Company Changsha China Hunan Province Key Laboratory of Intelligent Live Working Technology and Equipment (Robot) State Grid Hunan Power Transmission Maintenance Company Changsha China

ISBN: (数字)9781728175935

ISBN: (纸本)9781728175942

Due to the complex operation environment of transmission lines and many factors affecting lightning trip, it is difficult to realize real-time warning of lightning trip of transmission lines. This paper presents a new real-time warning method for lightning trip based on the combination of lightning location system, transmission line data and GA-BP neural network technology. Firstly, the factors affecting line tripping are determined and input data are preprocessed. Then, a lightning trip prediction model based on GA-BP neural network is established. The total number of lightning trips can be predicted by summing up the results of all the intervals of the line to be warned. Finally, according to the classification standard of early warning, the lightning trip warning of the whole line is realized. The example shows that the correct classification rate is 80%, the accuracy rate is 86.67%, the false alarm rate and the leakage alarm rate are 23.53% and 13.33% respectively. The performance index of the model is ideal, so the model has a good prediction effect for the real-time lightning trip warning of transmission lines.

关键词： Lightning Power transmission lines Real-time systems Poles and towers Genetic algorithms Biological neural networks Power transmission

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Design and Implementation of Log Data Analysis Management System Based on Hadoop

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Journal of Information Hiding and Privacy Protection 2020年第2期2卷 59-65页

作者： Dunhong Yao Yu Chen School of Computer Science and Engineering Huaihua UniversityHuaihua418000China Key Laboratory of Wuling-Mountain Health Big Data Intelligent Processing and Application in Hunan Province Universities Huaihua418000China Key Laboratory of Intelligent Control Technology for Wuling-Mountain Ecological Agriculture in Hunan Province Huaihua418000China School of Computer Science and Engineering Yulin Normal UniversityYulin537000China

With the rapid development of the Internet,many enterprises have launched their network *** users browse,search,and click the products of these platforms,most platforms will keep records of these network behaviors,these records are often heterogeneous,and it is called log *** effectively to analyze and manage these heterogeneous log data,so that enterprises can grasp the behavior characteristics of their platform users in time,to realize targeted recommendation of users,increase the sales volume of enterprises’products,and accelerate the development of ***,we follow the process of big data collection,storage,analysis,and visualization to design the system,then,we adopt HDFS storage technology,Yarn resource management technology,and gink load balancing technology to build a Hadoop cluster to process the log data,and adopt MapReduce processing technology and data warehouse hive technology analyze the log data to obtain the ***,the obtained results are displayed visually,and a log data analysis system is successfully *** has been proved by practice that the system effectively realizes the collection,analysis and visualization of log data,and can accurately realize the recommendation of products by *** system is stable and effective.

关键词： Log data Hadoop data analysis data visualization

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The role of 4D flow MRI in deep vein thrombosis research

Meta-Radiology

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Meta-Radiology 2025年第1期3卷

作者： Li, Meizhi Wu, Shangjie Liang, Xiao Gao, Chuanqi Hu, Muhua Chen, Zhu He, Pei Jia, Tingting Xiong, Li Department of Pulmonary and Critical Care Medicine The Second Xiangya Hospital of Central South University Changsha China Department of Medical Administration The Second Xiangya Hospital of Central South University Changsha China Clinical Medical Research Center for Pulmonary and Critical Care Medicine in Hunan Province Changsha China Hunan Research Centre for Evidence-based Medicine The Second Xiangya Hospital of Central South University Changsha China Department of Biomedical Engineering School of Basic Medical Science Central South University Changsha China Department of Radiology Second Xiangya Hospital Central South University Changsha China Hunan Key Laboratory for Super Microstructure and Ultrafast Process School of Physics and Electronics Central South University Changsha China National Engineering Research Center for Medical Big Data Application Technology and Big Data Institute Central South University Changsha China General Surgery Department of Second Xiangya Hospital Central South University Changsha China General Surgery Intelligent Healthcare Division of Clinical Medical Research Center of Hunan Province Changsha China

Four-dimensional (4D) flow Magnetic Resonance Imaging (MRI) technology has emerged as a valuable tool in angiography, offering unique insights into the hemodynamics and flow patterns. This research aims to explore the role of 4D flow MRI in advancing our understanding of Deep Vein Thrombosis (DVT), covering its applications in diagnosing, characterizing and mechanism of DVT, as well as its potential for guiding treatment strategies. The qualitative and quantitative information provided by 4D flow MRI enables a comprehensive assessment of blood flow in different vascular regions, shedding light on the relationship between hemodynamic changes and the onset and progression of vascular diseases. Nevertheless, most quantitative research findings for 4D hemodynamic indicators are lacking, and their use is mainly limited to examining arterial conditions. More exploration will be necessary to determine their applicability in studying venous vessels. © 2025 The Authors

关键词： 4D flow MRI Deep vein thrombosis Image analysis algorithms Noninvasive imaging

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A Study on The Portrait and Investigation Method of Stealing Electricity 2020

A Study on The Portrait and Investigation Method of Stealing...

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Proceedings of the 3rd International Conference on Information Technologies and Electrical Engineering

作者： Maotao Yang Xiangqi Xiao Yanjiao Huang Rui Huang Wencheng Xiao Liang Yang State Grid Hunan Electric Power Company Limited Power Supply Service Center(Metrology Center) Hunan Province Key Laboratory of Intelligent Electrical Measurement and Application Technology Changsha China State Grid Hunan management Training Center Changsha China China Resources Power Holdings Company Limited Shenzhen China Guangzhou Guangjian Construction Engineering Testing Center Co. Ltd. Guangzhou China

ISBN: (纸本)9781450388665

in this paper, we extract the data of the knowledge base, marketing business system, power information collection system, integrated power quantity and line loss management system, decompose the data dimension and extract the characteristics of electricity theft, draw the portrait of electricity theft behavior, construct the identification database of electricity theft behavior.

关键词： Multi-dimensional Feasibility Electricity Stealing

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Research on A Multi-Dimensional Intelligent Deduction and Risk Early Warning Evaluation Method of Electricity Stealing Situation 2020

Research on A Multi-Dimensional Intelligent Deduction and Ri...

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Proceedings of the 3rd International Conference on Information Technologies and Electrical Engineering

作者： Xiangqi Xiao Rui Huang Maotao Yang Wencheng Xiao Liang Yang Yanjiao Huang State Grid Hunan Electric Power Company Limited Power Supply Service Center(Metrology Center) Hunan Province Key Laboratory of Intelligent Electrical Measurement and Application Technology Changsha China China Resources Power Holdings Company Limited Shenzhen China Guangzhou Guangjian Construction Engineering Testing Center Co. Ltd. Guangzhou China State Grid Hunan management Training Center Changsha China

ISBN: (纸本)9781450388665

Currently, most researches on anti-electricity stealing technologies have not combined seasonal power consumption features, social and economic information for electric stealing situational warnings, and cannot effectively solve the problem of large workload and low accuracy in manual anti-electricity stealing monitoring. In addition, they cannot provide reliable technical support for front-line staff of electricity consumption inspection and anti-electricity stealing to accurately and efficiently carry out anti-electricity stealing analysis and investigation work. In view of this situation, this paper proposes a multi-dimensional intelligent deduction and risk early warning evaluation method of electricity stealing situation.

关键词： Risk Multi-dimensional Electricity Stealing

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