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Enantioselective Construction of Polycyclic Chromanes through Organocatalytic Sequential Quintuple Reaction via One-Pot Step-Wise Procedure

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Chinese Journal of Chemistry 2024年第18期42卷 2197-2202页

作者： Jie Wang hang Qin Ya-li Song Fei Cao Zhi-Hao You Key Laboratory of Pharmaceutical Quality Controlof Hebei Province College of Pharmaceutical SciencesHebei UniversityBaodingHebei 071002China Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of Education BaodingHebei 071002China

An efficient and highly stereoselective synthetic method to access polycyclic chromanes has been achieved through organocatalyzed one-pot step-wise reactions involving 2-hydroxycinnamaldehydes,2-aminochalcones,and malononitrile as *** reactions underwent a quintuple process by aza-Michael/Michael/Knoevenagel/oxa-Michael/aldol-type reaction in sequence to give products bearing 3 new generated rings and 5 chiral centers in moderate to quantitative yields with excellent stereoselectivities.

关键词： Asymmetric catalysis Organocatalysis Cyclization Quintuple reaction Polycycles Heterocycles Chromane One-pot reaction

Intelligent Predetermination of Generator Tripping Scheme: Knowledge Fusion-based Deep Reinforcement Learning Framework

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 66-75页

作者： lingkang Zeng Wei Yao Ze Hu hang Shuai Zhouping li Jinyu Wen Shijie Cheng State Key Laboratory of Advanced Electromagnetic Engineering and Technology School of Electrical and Electronics EngineeringHuazhong University of Science and TechnologyWuhan 430074China Dispatching and Control Center Central China Branch of State Grid Corporation of ChinaWuhan 430077China. Department of Electrical Engineering and Computer Science University of TennesseeKnoxvilleTN 37996USA

Generator tripping scheme(GTS)is the most commonly used scheme to prevent power systems from losing safety and ***,GTS is composed of offline predetermination and real-time scenario ***,it is extremely time-consuming and labor-intensive for manual predetermination for a large-scale modern power *** improve efficiency of predetermination,this paper proposes a framework of knowledge fusion-based deep reinforcement learning(KF-DRL)for intelligent predetermination of ***,the Markov Decision Process(MDP)for GTS problem is formulated based on transient instability ***,linear action space is developed to reduce dimensionality of action space for multiple controllable ***,KF-DRL leverages domain knowledge about GTS to mask invalid actions during the decision-making *** can enhance the efficiency and learning ***,the graph convolutional network(GCN)is introduced to the policy network for enhanced learning *** simulation results obtained on New England power system demonstrate superiority of the proposed KF-DRL framework for GTS over the purely data-driven DRL method.

关键词： Deep reinforcement learning generator tripping scheme graph convolutional network invalid action masking knowledgefusion

Variational quantum algorithm for node embedding

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Fundamental Research 2024年第4期4卷 845-850页

作者： Zeng-rong Zhou hang li Gui-Lu Long Research Center for Quantum Sensing Zhejiang LabHangzhou 311121China Bejing Academy of Quantum Information Sciences Beijing 100193China State Key Laboratory of Low-Dimensional Quantum Physics and Department of Physics Tsinghua UniversityBeijing 100084China

Quantum machine learning has made remarkable progress in many important ***,the gate complexity of the initial state preparation is seldom considered in lots of quantum machine learning algorithms,making them ***,we propose a quantum algorithm for the node embedding problem that maps a node graph's topological structure to embedding *** resulting quantum embedding state can be used as an input for other quantum machine learning *** O(log(N))qubits to store the information of N nodes,our algorithm will not lose quantum advantage for the subsequent quantum information ***,owing to the use of a parameterized quantum circuit with O(poly(log(N)))depth,the resulting state can serve as an efficient quantum *** addition,we explored the measurement complexity of the quantum node embedding algorithm,which is the main issue in training parameters,and extended the algorithm to capture high-order neighborhood information between ***,we experimentally demonstrated our algorithm on an nuclear magnetic resonance quantum processor to solve a graph model.

关键词： Quantum machine learning Quantum computation Node embedding Variational quantum algorithm Nuclear magnetic resonance

EVEscape: Revealing potential escape sites based on the viral variation landscape

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Biophysics Reports 2024年第2期10卷 133-134页

作者： Yaling li Aiping Wu hang-Yu Zhou Zhejiang Lab State Key Laboratory of Common Mechanism Research for Major Diseases Suzhou Institute of Systems MedicineChinese Academy of Medical Sciences & Peking Union Medical College

The continuous mutation and evolution of viruses to evade the host immune response present a formidable challenge to combating infectious diseases. Accurate prediction of viral immune escape sites is crucial for disease diagnosis, therapy development, vaccine design, and other strategies aimed at combating emerging infectious diseases. During the COVID-19 pandemic,

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Mechanism research progress on transition metal compound electrode materials for supercapacitors

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Rare Metals 2024年第9期43卷 4076-4098页

作者： Zhi-Hui Xu Xue-Lei li Qing-Wen li Kai Lv Jing-Shun liu Xiu-Kun hang Aruuhan Bayaguud School of Materials Science and Engineering Inner Mongolia University of TechnologyHohhot 010051China School of Materials Science and Engineering Tianjin University of TechnologyTianjin 300384China College of Chemistry and Chemical Engineering Inner Mongolia UniversityHohhot 010021China

Supercapacitors(SCs)have remarkable energy storage capabilities and have garnered considerable interest due to their superior power densities and ultra-long cycling ***,their comparatively low energy density limits their extensive application in large-scale commercial *** materials directly affect the performance of ***,the development of cutting-edge electrode materials and modification of their morphological and structural properties are vital for advancing the performance of *** metal compounds have a high specific capacity and good cycling durability,making them the most promising electrode active materials for high-energy density ***,their inadequate conductivity,unfavorable ion diffusion rates,substantial volume expansion and phase transitions during charging and discharging are obstacles to their stable and efficient integration into *** address these challenges,this study provides a comprehensive summary of the current advancements in transition metal nanomaterials as electrode materials for SCs,an overview of the current research status,and the prevailing ***,this study highlights synthetic techniques and management strategies for electrode materials derived from transition metal compounds,targeting the resolution of the aforementioned ***,a concise discussion is provided on the future directions of SC development,with an emphasis on the utilization of transition metal compound electrode materials.

关键词： Supercapacitors Transition metal compounds electrode Existing problems Synthetic methods Regulation strategies

Iron–doped bismuth oxybromides as visible-light-responsive Fenton catalysts for the degradation of atrazine in aqueous phases

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Journal of Environmental Sciences 2024年第3期137卷 321-332页

作者： Yong-li Cai Yu-hang Xu Ji-Zun Xiang Zhi-Qiang Zhang Qiu-Xiang He Ya-Feng li Jian Lü Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation College of Resources and EnvironmentFujian Agriculture and Forestry UniversityFuzhou 350002China State Key Laboratory of Photocatalysis on Energy and Environment Fuzhou UniversityFuzhou 350116China

Pesticides and its degradation products,being well–known residues in soil,have recently been detected in many water bodies as pollutants of emerging concerns,and thus there is a contemporary demand to develop viable and cost–effective techniques for the removal of related organic pollutants in aqueous ***,a visible-light-responsive Fenton system was constructed with iron–doped bismuth oxybromides(Fe–BiOBr)as the *** the advantage of sustainable Fe(Ⅲ)/Fe(Ⅱ)conversion and optimized H_(2)O_(2)utilization,the optimal Fe–BiOBr–2 catalyst showed an excellent atrazine removal efficiency of 97.61%in 120 min,which is superior than the traditional homogeneous Fenton and the majority of heterogeneous processes documented in the *** this photo–Fenton system,hydroxyl(·OH)and superoxide(·O_(2)^(-))radicals were dominant active species contributed to the oxidative degradation of *** to the production of various active radicals,five degradation pathways were proposed based on the identification of intermediates and degradation ***,this work not only demonstrates a fundamental insight into creating highly efficient and atom economic photo-Fenton systems,but also provides a complementary strategy for the treatment of organic pollutants in water.

关键词： Bismuth oxybromide Photo–Fenton Atrazine Catalytic degradation

Rational design of superior catalysts from topological semimetals with nontrivial energy window

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Rare Metals 2024年第5期43卷 1956-1964页

作者： Min Zhao li-Rong Wang Wei liu Ming-hang li Ying liu Xue-Fang Dai Guo-Dong liu Xiao-Ming Zhang Key Laboratory of Reliability and Intelligence of Electrical Equipment School of Materials Science and Engineering ManufacturingHebei University of TechnologyTianjin 300130China

Materials featuring topological energy bands and nontrivial surface states hold significant promise in unlocking unprecedented opportunities for innovating electrocatalytic ***,it remains a challenge to realize superior topological catalysts which can carry both high catalytic activity and excellent catalytic ***,we propose that a family of Ni-based binary materials hosting fantasying topological conjunct-nodalpoint state and a large nontrivial energy window(NEWD)represents an ideal choice for such superior topological catalysts in hydrogen evolution *** presence of conjunct-nodal-points ensures long Fermi arcs on the surface,thereby enabling an extremely high catalytic *** NEWD plays a crucial role in stabilizing the high catalytic activity against external perturbations,such as strain and electron/hole *** roles for conjunctnodal-points and NEWD are substantiated by the observable weakening of catalytic performance during topological phase transitions,which result in the removal of the conjunct-nodal-points,NEWD and their corresponding long Fermi *** work unveils a hidden mechanism and opens a feasible route for developing superior quantum catalysts from novel topology point of view.

关键词： First-principles modeling Topological semimetal Nontrivial surface states Hydrogen evolution reaction

Acoustofluidics-enhanced biosensing with simultaneously high sensitivity and speed

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Microsystems & Nanoengineering 2024年第3期10卷 335-346页

作者： Yuang li Yang Zhao Yang Yang Wenchang Zhang Yun Zhang Sheng Sun lingqian Zhang Mingxiao li hang Gao Chengjun Huang Institute of Microelectronics of the Chinese Academy of Sciences Beijing 100029P.R.China University of Chinese Academy of Sciences Beijing 101408P.R.China Department of Medicine Brigham and Women’s HospitalHarvard Medical SchoolBostonMA 02115USA

Simultaneously achieving high sensitivity and detection speed with traditional solid-state biosensors is usually limited since the target molecules must passively diffuse to the sensor surface before they can be *** techniques have been applied to shorten the diffusion time by continuously moving molecules through the biosensing ***,the binding efficiencies of the biomolecules are still limited by the inherent laminar flow inside microscale *** this study,focused traveling surface acoustic waves were directed into an acoustic microfluidic chip,which could continuously enrich the target molecules into a constriction zone for immediate detection of the immune reactions,thus significantly improving the detection sensitivity and *** demonstrate the enhancement of biosensing,we first developed an acoustic microfluidic chip integrated with a focused interdigital transducer;this transducer had the ability to capture more than 91%of passed ***,polystyrene microbeads were pre-captured with human IgG molecules at different concentrations and loaded for detection on the *** representative results,~0.63,2.62,11.78,and 19.75 seconds were needed to accumulate significant numbers of microbeads pre-captured with human IgG molecules at concentrations of 100,10,1,and 0.1 ng/mL(~0.7 pM),respectively;this process was faster than the other methods at the hour level and more sensitive than the other methods at the nanomolar *** results indicated that the proposed method could significantly improve both the sensitivity and speed,revealing the importance of selective enrichment strategies for rapid biosensing of rare molecules.

关键词： fluid continuously simultaneous

The Changes of Histone Methylation Induced by Adolescent Social Stress Regulate the Resting-State Activity in mPFC

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Research 2024年第3期2023卷 273-283页

作者： Jiesi Wang Wei Zhang hang Xu Bart Ellenbroek Jiajie Dai li Wang Chaogan Yan Weiwen Wang CAS Key Laboratory of Mental Health Institute of PsychologyChinese Academy of SciencesBeijing.China Department of Psychology University of Chinese Academy of SciencesBeijingChina School of Psychology Victoria University of WellingtonKelburnWellington 6012New Zealand CAS Key Laboratory of Behavioral Science Institute of PsychologyChinese Academy of SciencesBeijingChina.

Early-life stress can lead to sustained alterations in regional resting-state brain functions, but the underlying molecular mechanism remains unclear. Stress can also induce sustained changes in epigenetic modifications across brain regions, which are not limited to a few genes;rather, they often tend to produce global levels of change. The functional implication of these changes also remains to be elucidated. We hypothesize that global epigenetic changes may partly modulate the resting-state functions of brain regions to influence behavior. To test this hypothesis, we used an adolescent social stress (ASS) model in mice and examined the relationship between epigenetic modifications and regional resting-state brain activity using resting-state functional magnetic resonance imaging (rs-fMRI). The results showed that, compared to the control mice, the stressed mice showed increased anxiety and social avoidance behaviors and greater levels of dimethylation of histone H3 at lysine 9 (H3K9me2) in the medial prefrontal cortex (mPFC). In addition, the resting-state activity represented by the amplitude of low-frequency fluctuation (ALFF) was significantly lower in the mPFC of stressed mice. To verify the relationship of H3K9me2 and ALFF, the specific inhibition of H3Kme2 was performed by using the drug UNC0642, which reversed the anxiety behavior induced by ASS and significantly increase the ALFF value of mPFC in both normal and ASS animals. Our study is the first to report an association between histone modifications and rs-fMRI findings, providing a new perspective for understanding of the significance of regional brain epigenetic changes and a possible molecular explanation for rs-fMRI findings.

关键词： sustained mPFC alterations