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Stereoselective Addition of N-Alkylhydroxylamines to α,β-Unsaturated Nitro Compounds

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Chinese Chemical Letters 2006年第7期17卷 859-862页

作者： Ai Jun LI ji cheng chu Hong Sheng GUO Xue Qin ZHOU Dong Zhi LIU School of Chemical Engineering and Technology Tianjin University Tianjin 300072 Medical College Chinese People＇s Armed Police Force Tianjin 300071

N-Alkylhydroxylamines have been shown to undergo a stereospecific cis addition to 1-phenyl-2 -nitropropene compounds, whereas the corresponding O-alkylhydroxylamines give no diastereoselectivity. The concerted additio... 详细信息

关键词： N-Alkylhydroxylamines O-alkylhydroxylamines concerted addition mechanism α,β-unsaturated nitro compounds stereoselectivity.

Bilinear magnetoelectric resistance induced by spin Hall effect

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Science China Materials 2025年第2期68卷 687-688页

作者： Ruiyue chu cheng Song School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

Magnetoresistance(MR)is a fundamental transport phenomenon crucial for reading magnetic *** also plays a key role in understanding how time-reversal symmetry breaking affects electrical *** discoveries of anisotropic MR[1],giant MR[2],tunneling MR[3],and spin Hall magnetoresistance[4]have driven the development of diverse spintronic devices used in data storage,computing,and sensing ***,these MR effects do not scale linearly with the electric field(and thus,electric current).Recently,nonlinear MR,which scales specifically with the electric current(Ic),has been *** magnetic/non-magnetic bilayers,unidirectional spin Hall magnetoresistance(USMR)[5]shows a linear dependence on Ic,with voltage scaling quadratically with the applied electric field,due to interfacial spin-dependent and electron-magnon scattering mechanisms.

关键词： breaking symmetry linearly

Prospects on mangrove knowledge services in the smart era:From plant atlas to knowledge graphs

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Science China Earth Sciences 2025年第1期68卷 111-127页

作者： Zhi-Wei HOU Wenlong jiNG cheng-Zhi QIN ji YANG Qing XIA Xiaoling YIN Key Laboratory of Guangdong for Utilization of Remote Sensing and Geographical Information System Guangdong Open Laboratory of Geospatial Information Technology and ApplicationGuangzhou Institute of GeographyGuangdong Academy of SciencesGuangzhou510070China Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) Guangzhou511458China State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing100049China School of Traffic&Transportation Engineering Changsha University of Science and TechnologyChangsha410114China

Mangroves are crucial to the ecological security of the Earth and human *** management,conservation,and restoration are of great importance and necessitate the support of spatio-temporal information and multidisciplinary knowledge such as biology and *** knowledge services such as plant atlas provide illustrated textual knowledge of ***,this kind of service is oriented to information retrieval and is incapable of effectively mining and utilizing fragmented knowledge from multi-source heterogeneous data,facing the problem of“massive data,rare knowledge”.Knowledge graphs are capable of extracting,organizing,and fusing the knowledge contained in massive data into semantic networks that can be understood and computed by *** provide a solution for the realization of intelligent knowledge *** on the urgent need for mangrove knowledge acquisition,formal representation,and intelligent services,this paper proposes a research prospect on mangrove knowledge graphs and knowledge *** first analyze the similarities and differences between various domain-specific concepts of *** this basis,we define the mangrove knowledge graph as a large-scale knowledge base that integrates multi-disciplinary knowledge and spatio-temporal information with mangrove ecosystems as the ***,we propose a research framework for mangrove knowledge services that can realize the transformation from multi-modal data to intelligent knowledge services,including multiple research levels such as ubiquitous data sensing and aggregation,knowledge organization and graph construction,and intelligent mangrove knowledge ***,the methods and workflow for constructing mangrove knowledge graphs are ***,we discuss the challenges and possible future directions of mangrove knowledge services in the smart era,including the construction of a mangrove knowledge system that integrates the domain-specific charac

关键词： Mangrove Tupu Knowledge graph Multi-modal Knowledge service

Recent advances in semi-heterogenous photocatalysis in organic synthesis

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Chinese Chemical Letters 2025年第2期36卷 94-117页

作者： jia-cheng Hou Wei Cai Hong-Tao ji Li-Juan Ou Wei-Min He School of Chemistry and Chemical Engineering University of South China School of Pharmaceutical Sciences Hunan University of Medicine School of Materials Science and Engineering Hunan Institute of Technology

Semi-heterogeneous photocatalysis has emerged as a powerful and productive platform in organic chemistry, which provides mild and eco-friendly conditions for a diverse range of bond-forming *** synergy of homogeneous catalysts and heterogeneous catalysts inherits their main advantages, such as higher activities, easy separation and superior recyclability. In this review, we summarize the recent advances in recyclable semi-heterogenous protocols for the light promoted bond-forming reactions and identify directions for future research according to the different photocatalysts/metal/redox catalysts involved. Notably, this review is not a comprehensive description of reported literature but aim to highlight and illustrate key concepts, strategies, reaction model, reaction conditions and mechanisms.

关键词： Bond-forming Organic synthesis Photocatalysis Recyclable Semi-heterogeneous

A nuclide identification method ofγspectrum and model building based on the transformer

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Nuclear Science and Techniques 2025年第1期36卷 80-93页

作者： Fei Li chu-Yang Luo Ying-Zi Wen Sheng Lv Feng cheng Guo-Qiang Zeng jian-Feng jiang Bing-Hai Li College of Nuclear Technology and Automation Engineering Chengdu University of TechnologyChengdu 610000China Applied Nuclear Technology in Geosciences Key Laboratory of Sichuan Province Chengdu 610000China Department of Physics Universitat Politècnica de CatalunyaBarcelona 08028Spain Airborne Survey and Remote Sensing Center of Nuclear Industry Shijiazhuang 050000China Hebei Key Laboratory of Airborne Detection and Remote Sensing Technology Shijiazhuang 050000China

In current neural network algorithms for nuclide identification in high-background,poor-resolution detectors,traditional network paradigms including back-propagation networks,convolutional neural networks,recurrent neural networks,etc.,have been limited in research on γ spectrum analysis because of their inherent mathematical *** is difficult to make progress in terms of training data requirements and prediction *** contrast to traditional network paradigms,network models based on the transformer structure have the characteristics of parallel computing,position encoding,and deep stacking,which have enabled good performance in natural language processing tasks in recent ***,in this paper,a transformer-based neural network (TBNN) model is proposed to achieve nuclide identification for the first ***,the Geant4 program was used to generate the basic single-nuclide energy spectrum through Monte Carlo simulations.A multi-nuclide energy spectrum database was established for neural network training using random matrices of γ-ray energy,activity,and *** on the encoder–decoder structure,a network topology based on the transformer was built,transforming the 1024-channel energy spectrum data into a 32×32 energy spectrum sequence as the model *** experiments and adjustments of model parameters,including the learning rate of the TBNN model,number of attention heads,and number of network stacking layers,the overall recognition rate reached 98.7%.Additionally,this database was used for training AI models such as back-propagation networks,convolutional neural networks,residual networks,and long shortterm memory neural networks,with overall recognition rates of 92.8%,95.3%,96.3%,and 96.6%,*** indicates that the TBNN model exhibited better nuclide identification among these AI models,providing an important reference and theoretical basis for the practical application of transformers in the qualitative and quantitativ

关键词： Nuclide identification Neural network Transformer

Neurotransmitter-mediated artificial synapses based on organic electrochemical transistors for future biomimic and bioinspired neuromorphic systems

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Journal of Semiconductors 2025年第1期46卷 78-89页

作者： Miao cheng Yifan Xie jinyao Wang Qingqing jin Yue Tian Changrui Liu jingyun chu Mengmeng Li Ling Li Key Lab of Fabrication Technologies for Integrated Circuits Chinese Academy of SciencesBeijing 100029China Institute of Microelectronics Chinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences 100049 BeijingChina

Organic electrochemical transistors have emerged as a solution for artificial synapses that mimic the neural functions of the brain structure,holding great potentials to break the bottleneck of von Neumann ***,current artificial synapses rely primarily on electrical signals,and little attention has been paid to the vital role of neurotransmitter-mediated artificial *** is a key neurotransmitter associated with emotion regulation and cognitive processes that needs to be monitored in real time to advance the development of disease diagnostics and *** provide insights into the development of artificial synapses with neurotransmitter involvement,this review proposes three steps towards future biomimic and bioinspired neuromorphic *** first summarize OECT-based dopamine detection devices,and then review advances in neurotransmitter-mediated artificial synapses and resultant advanced neuromorphic ***,by exploring the challenges and opportunities related to such neuromorphic systems,we provide a perspective on the future development of biomimetic and bioinspired neuromorphic systems.

关键词： artificial synapses organic electrochemical transistors neurotransmitters neuromorphic systems

Interannual succession of phytoplankton community in a canyon-shaped drinking water reservoir during the initial impoundment period:Taxonomic versus functional groups

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Journal of Environmental Sciences 2025年第5期151卷 454-468页

作者： Yi Hou Ya cheng Kai Li Meng Yang Kangzhe Huang Gang ji Ruikang Xue Tinglin Huang Gang Wen Shaanxi Provincial Field Scientific Observation and Research Station of Water Quality in Qinling Mountains Xi’an University of Architecture and TechnologyXi’an 710055China Key Laboratory of Northwest Water Resource Environment and EcologyMOEXi’an University of Architecture and TechnologyXi’an 710055China School of Environmental and Municipal Engineering Xi’an University of Architecture and TechnologyXi’an 710055China

During the initial impoundment period of a canyon-shaped reservoir,the water body fluctuated violently regarding water level,hydrological condition,and thermal *** variations may alter the structure of phytoplankton community,resulting in algal blooms and seriously threatening the ecological security of the *** is of great significance to understand the continuous changes of phytoplankton in the initial impoundment period for the protection of reservoir water ***,a two-year in-situ monitoring study was conducted on water quality and phytoplankton in a representative canyonshaped reservoir named Sanhekou and the interannual changes of phytoplankton community and its response to environmental changes during the initial impoundment period were discussed at taxonomic versus functional classification *** results showed that the total nitrogen and permanganate index levels were relatively high in the first year due to rapid water storage and heavy rainfall input,and the more stable hydrological conditions in the second year promoted the increase of algae density and the transformation of community,and the proportion of cyanobacteria increased *** succession order of phytoplankton in the first year of the initial impoundment periodwas Chlorophyta-Bacillariophyta-Chlorophyta,or J/F/X1-P/MP/W1-A/X1/MP,*** the succession order in the second year was Cyanobacteria/Chlorophyta-Bacillariophyta-Chlorophyta,or L_(M)/G/P-P/A/X1-X1/J/*** temperature,relativewater column stability,mixing depth,and pHwere crucial factors affecting phytoplankton community *** study revealed the interannual succession law and driving factors of phytoplankton in the initial impoundment period and provided an important reference for the operation management and ecological protection of canyon-shaped reservoirs.

关键词： Canyon-shaped reservoir Functional groups Initial impoundment Interannual succession Water quality

Integrating well logs, 3D seismic, and earthquake data for comprehensive prediction of 3D in-situ stress orientations: A case study from the Weiyuan area in the Sichuan Basin, China

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Petroleum Science 2025年第1期22卷 210-221页

作者： Huan Cao Yang Zhao Hai-Chao Chen Le-Le Zhang cheng-Gang Xian ji-Dong Yang Lu Liu State Key Laboratory of Petroleum Resources and Engineering and Unconventional Petroleum Research Institute China University of Petroleum (Beijing) Department of Geophysics China University of Petroleum (East China) Aramco Beijing Research Center Aramco Asia

Determining the orientation of in-situ stresses is crucial for various geoscience and engineering applications. Conventional methods for estimating these stress orientations often depend on focal mechanism solutions(FMSs) derived from earthquake data and formation micro-imager(FMI) data from well ***, these techniques can be costly, depth-inaccurate, and may lack spatial coverage. To address this issue, we introduce the use of three-dimensional(3D) seismic data(active sources) as a lateral constraint to approximate the 3D stress orientation field. Recognizing that both stress and fracture patterns are closely related to seismic velocity anisotropy, we derive the orientation of azimuthal anisotropy from multi-azimuth 3D seismic data to compensate for the lack of spatial stress orientation information. We apply our proposed workflow to a case study in the Weiyuan area of the Sichuan Basin, China, a region targeted for shale gas production. By integrating diverse datasets, including 3D seismic, earthquakes, and well logs, we develop a comprehensive 3D model of in-situ stress(orientations and magnitudes). Our results demonstrate that the estimated anisotropy orientations from 3D seismic data are consistent with the direction of maximum horizontal principal stress(SHmax) obtained from FMIs. We analyzed 12earthquakes(magnitude > 3) recorded between 2016 and 2020 for their FMSs and compressional axis(Paxis) orientations. The derived SHmax direction from our 3D stress model is 110°ES(East-South), which shows excellent agreement with the FMSs(within 3.96°). This close alignment validates the reliability and precision of our integrated method for predicting 3D SHmax orientations.

关键词： In-situ stress orientation SHmax Azimuthal velocity anisotropy Focal source mechanism Formation micro-imager

Nanomaterials-mediated lysosomal regulation:a robust protein-clearance approach for the treatment of Alzheimer’s disease

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Neural Regeneration Research 2025年第2期20卷 424-439页

作者： Mengqi Hao jianjian chu Tinglin Zhang Tong Yin Yuankai Gu Wendanqi Liang Wenbo ji jianhua Zhuang Yan Liu jie Gao You Yin Department of Neurology Second Affiliated Hospital of Naval Medical University(Shanghai Changzheng Hospital)ShanghaiChina School of Health Science and Engineering University of Shanghai for Science and TechnologyShanghaiChina Changhai Clinical Research Unit Shanghai Changhai HospitalNaval Medical UniversityShanghaiChina Department of Clinical Pharmacy Xinhua HospitalShanghai Jiao Tong University School of MedicineShanghaiChina Department of Neurology Shanghai East HospitalSchool of MedicineTongji UniversityShanghaiChina

Alzheimer’s disease is a debilitating,progressive neurodegenerative disorder characterized by the progressive accumulation of abnormal proteins,including amyloid plaques and intracellular tau tangles,primarily within the ***,crucial intracellular organelles responsible for protein degradation,play a key role in maintaining cellular *** studies have suggested a link between the dysregulation of the lysosomal system and pathogenesis of neurodegenerative diseases,including Alzheimer’s *** the normal physiological function of lysosomes hold the potential to reduce the pathological burden and improve the symptoms of Alzheimer’s ***,the efficacy of drugs in treating Alzheimer’s disease is limited,with major challenges in drug delivery efficiency and ***,nanomaterials have gained widespread use in Alzheimer’s disease drug research owing to their favorable physical and chemical *** review aims to provide a comprehensive overview of recent advances in using nanomaterials(polymeric nanomaterials,nanoemulsions,and carbon-based nanomaterials)to enhance lysosomal function in treating Alzheimer’s *** review also explores new concepts and potential therapeutic strategies for Alzheimer’s disease through the integration of nanomaterials and modulation of lysosomal *** conclusion,this review emphasizes the potential of nanomaterials in modulating lysosomal function to improve the pathological features of Alzheimer’s *** application of nanotechnology to the development of Alzheimer’s disease drugs brings new ideas and approaches for future treatment of this disease.

关键词： Alzheimer’s disease autophagy dysfunction lysosomal acidification lysosomal system nanomaterials neurodegenerative diseases