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Chinese Chemical Letters 2024年第2期35卷 484-488页

作者： Hao Zhang Qian Liu Zhurui shen School of Materials Science and Engineering Nankai UniversityTianjin 300350China

Photoreduction of CO_(2) to solar fuels has caused great interest,but suffers from low catalytic efficiency and poor ***,we designed a S-scheme heterojunction(Cu-TiO_(2)/WO_(3))with Cu single atom to significantly boost the photoreduction of CO_(2).Notably,the developed Cu-TiO_(2)/WO_(3) achieved the solardriven conversion of CO_(2) to CH_(4) with an evolution rate of 98.69μmol g^(−1) h^(−1),and the electron selectivity of CH_(4) reached 88.5%.The yield was much higher than those of pristine WO_(3),TiO_(2)/WO_(3) and Cu-TiO_(2) *** and theoretical analysis suggested that the S-scheme heterojunction accelerated charge migration and inhibited the recombination of electron-hole ***,the charge separation effect of the heterojunction meliorated the position of the *** uplifted d-band centers of Cu and Ti on Cu-TiO_(2)/WO_(3) not only improved the electron interaction between Cu single atoms and substrate-TiO_(2),accelerated the adsorption and activation of CO_(2) on the active sites of Cu single atom,but also optimized the Gibbs free energies of CH 4 formation pathway,leading to excellent selectivity toward CH_(4).This work provides new insights into the design of photocatalyst systems with high photocatalytic performance.

关键词： Cu single atom Heterojunction CO_(2)photoreduction d-band center DFT

The Faber Operator Acting on BMOA, BMO-Teichmüller Space and Chord-arc Curves

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Acta Mathematica Sinica,English Series 2024年第10期40卷 2359-2387页

作者： Tai Liang LIU Yu Liang shen Department of Mathematics Soochow University

After reviewing Grunsky operator and Faber operator acting on Dirichlet space, we discuss the boundedness of Faber operator on BMOA, a new subject which turns out to be closely related to the BMO theory of the universal Teichmüller space. In particular, we show that the Faber operator acts as a bounded operator on BMOA if the symbol conformal map stays nearly to the base point in the BMO-Teichmüller space. Meanwhile, we obtain several results on quasiconformal mappings, BMOTeichm¨uller space and chord-arc curves as well. As by-products, this provides a complex analysis approach to the boundedness of the Cauchy integral acting on BMO functions on a chord-arc curve near to the unit circle in the BMO-Teichmüller space.

关键词： 30C62 30H35 32G15 BMO BMO-Teichmüller space BMOA Carleson measure Cauchy integral chord-arc curve Faber operator Grunsky operator quasicircle quasiconformal mapping

Recent advances in the culture-independent discovery of natural products using metagenomic approaches

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Chinese Journal of Natural Medicines 2024年第2期22卷 100-111页

作者： shen Yiping LIU Nan WANG Zongqiang Laboratory of Microbial Drug Discovery China Pharmaceutical UniversityNanjing 211198China

Natural products derived from bacterial sources have long been pivotal in the discovery of drug ***,the cultivation of only about 1%of bacteria in laboratory settings has left a significant portion of biosynthetic diversity hidden within the genomes of uncultured *** in sequencing technologies now enable the exploration of genetic material from these metagenomes through culture-independent *** approach involves extracting genetic sequences from environmental DNA and applying a hybrid methodology that combines functional screening,sequence tag-based homology screening,and bioinformatic-assisted chemical *** this process,numerous valuable natural products have been identified and synthesized from previously uncharted metagenomic *** paper provides an overview of the recent advancements in the utilization of culture-independent techniques for the discovery of novel biosynthetic gene clusters and bioactive small molecules within metagenomic libraries.

关键词： Metagenomics Culture-independent approach Natural product Functional screening Sequence tag-based homology screening Syn-BNP

Structure and Representations for Electrical Lie Algebra of Type D_(5)

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Algebra Colloquium 2024年第2期31卷 271-284页

作者： Yulu Chen Ran shen Yucai Su College of Science Donghua UniversityShanghai 201620China 不详

In this paper,we prove that the electrical Lie algebra e D_(5)is isomorphic to the semidirect product of sp_(4)and a 2-step nilpotent Lie ***,we classify the irreducible highest weight modules for e D_(5).

关键词： electrical Lie algebra 2-step nilpotent Lie algebra highest weight module

Stereoselective Synthesis of 2-Deoxy-α-N-Glycosides from Glycals with 1,4,2-Dioxazol-5-ones

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Chinese Journal of Chemistry 2024年第18期42卷 2147-2152页

作者： Zhenpeng shen Guoyin Yin Yangyang Li The Institute for Advanced Studies Wuhan UniversityWuhanHubei 430072China

The synthesis of N-glycosides has received significant attention due to their crucial role in carbohydrate *** considerable advancements developed in the construction of N-glycosides,methods for the stereoselective construction of 2-deoxy-α-N-glycosides are still ***,we disclosed a nickel-catalyzed hydroamination of glycals under mild *** transformation could allow for the stereoselective synthesis of an array of 2-deoxy-α-N-glycosides with excellentα-***-catalyzed glycosylation reactions,particularly those involving anomeric C(sp")-metal bond formation,have proven to be an effective and stereoselective strategy for producing various ***,with highlight of the application of this reaction,y-sugar amino acidderivatives weresynthesized.

关键词： 2-Deoxy-α-N-glycosides Nickel catalysis Stereoselectivity Glycals Hydroamination Amides Glycosylation Alkenes ComprehensiveSummary

Second-order error analysis of the averaged L1 scheme L1 for time-fractional initial-value and subdiffusion problems

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Science China Mathematics 2024年第7期67卷 1641-1664页

作者： Jinye shen Fanhai Zeng Martin Stynes School of Mathematics Southwestern University of Finance and EconomicsChengdu611130China School of Mathematics Shandong UniversityJinan250100China Applied and Computational Mathematics Division Beijing Computational Science Research CenterBeijing100193China

Fractional initial-value problems(IVPs) and time-fractional initial-boundary value problems(IBVPs), each with a Caputo temporal derivative of order α ∈(0, 1), are considered. An averaged variant of the well-known L1 scheme is proved to be O(N^(-2)) convergent for IVPs on suitably graded meshes with N points, thereby improving the O(N^(-(2-α))) convergence rate of the standard L1 scheme. The analysis relies on a delicate decomposition of the temporal truncation error that yields a sharp dependence of the order of convergence on the degree of mesh grading used. This averaged L1 scheme can be combined with a finite difference or piecewise linear finite element discretization in space for IBVPs, and under a restriction on the temporal mesh width, one gets again O(N^(-2)) convergence in time, together with O(h^(2)) convergence in space,where h is the spatial mesh width. Numerical experiments support our results.

关键词： time-fractional subdiffusion averaged L1 scheme

Polymer Mechanochemistry on Reactive Species Generated from Mechanochemical Reactions

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Chinese Journal of Chemistry 2024年第12期42卷 1418-1432页

作者： Xiaolong Chen Hang shen Zhengbiao Zhang State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials Suzhou Key Laboratory of Macromolecular Design and Precision SynthesisCollege of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhouJiangsu 215123China

Comprehensive Summary Polymer mechanochemistry on reactive species has attracted more and more attentions over the past 20 years,as the mechanochemical generation of reactive species has a great potential in developing different polymeric materials for various purposes,such as stress detection,self-healing,self-strengthening,controllable degradation and release of small *** this review,we first discuss the recent progress on polymer mechanochemistry of the reactive species that are generated from the mechanochemical reactions of *** types of reactive species,including radical,zwitterion,ionic,carbene and neutral intermediates,and their applications were reviewed in *** mechanochemical reactions are sensitive to the mechanophore structure and polymer framework,we then discuss how mechanophore isomerism,polymer structure,polymer attachment point,and polymer architecture influence the mechanophore *** last,we provide our perspectives on the polymer mechanochemistry of reactivespecies.

关键词： Stimuli-responsive polymers Polymer mechanochemistry Mechanophore Mechanochemical reaction Reactive species

A Novel Locomotion Rule Rmbedding Long Short-Term Memory Network with Attention for Human Locomotor Intent Classification Using Multi-Sensors Signals

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Computers, Materials & Continua 2024年第6期79卷 4349-4370页

作者： Jiajie shen Yan Wang Dongxu Zhang Key Laboratory of Symbol Computation and Knowledge Engineering Ministry of EducationColleague of Computer Science and TechnologyJilin UniversityChangchun130012China College of Software and Key Laboratory of Symbolic Computation and Knowledge Engineering of Ministry of EducationJilin UniversityChangchun130012China

Locomotor intent classification has become a research hotspot due to its importance to the development of assistive robotics and wearable *** work have achieved impressive performance in classifying steady locomotion ***,it remains challenging for these methods to attain high accuracy when facing transitions between steady locomotion *** to the similarities between the information of the transitions and their adjacent steady ***,most of these methods rely solely on data and overlook the objective laws between physical activities,resulting in lower accuracy,particularly when encountering complex locomotion modes such as *** address the existing deficiencies,we propose the locomotion rule embedding long short-term memory(LSTM)network with Attention(LREAL)for human locomotor intent classification,with a particular focus on transitions,using data from fewer sensors(two inertial measurement units and four goniometers).The LREAL network consists of two levels:One responsible for distinguishing between steady states and transitions,and the other for the accurate identification of locomotor *** classifier in these levels is composed of multiple-LSTM layers and an attention *** introduce real-world motion rules and apply constraints to the network,a prior knowledge was added to the network via a rule-modulating *** method was tested on the ENABL3S dataset,which contains continuous locomotion date for seven steady and twelve transitions *** results showed that the LREAL network could recognize locomotor intents with an average accuracy of 99.03%and 96.52%for the steady and transitions states,*** is worth noting that the LREAL network accuracy for transition-state recognition improved by 0.18%compared to other state-of-the-art network,while using data from fewer sensors.

关键词： Lower-limb prosthetics deep neural networks motion classification

稀土聚环氧丙烷的合成及其碱土金属盐复合物的电性能

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石油化工 1990年第4期19卷 218-222页

作者：杨慕杰查丛向沈之荃浙江大学化学系杭州310027

以稀土化合物-环烷酸钕盐 Nd(naph)_3、三异丁基铝和水组成络合催化剂,在甲苯溶液中引发环氧丙烷聚合。研究了聚合规律,制得分子量达150万、结晶度可达35%的聚环氧丙烷(PPO)。首次合成PPO与碱土金属盐复合物 CaCl_2·(PPO)_n 和 MgCl_2... 详细信息

以稀土化合物-环烷酸钕盐 Nd(naph)_3、三异丁基铝和水组成络合催化剂,在甲苯溶液中引发环氧丙烷聚合。研究了聚合规律,制得分子量达150万、结晶度可达35%的聚环氧丙烷(PPO)。首次合成PPO与碱土金属盐复合物 CaCl_2·(PPO)_n 和 MgCl_2·(PPO)_n。研究了复合物的制备方法,电导与其热历史和结晶性的关系,以及碱土金属盐的种类及浓度对电导的影响。MgCl_2·(PPO)_8的电导在80℃时可达7.4×10^(15)Ω^(-1)·cm^(-1)。

关键词：稀土聚环氧丙烷碱土金属盐

A scoping review of methodologies for applying artificial intelligence to physical activity interventions

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Journal of Sport and Health Science 2024年第3期13卷 428-441页

作者： Ruopeng An Jing shen Junjie Wang Yuyi Yang Brown School Washington UniversitySt.LouisMO 63130USA Department of Physical Education China University of Geosciences BeijingBeijing 100083China School of Kinesiology and Health Promotion Dalian University of TechnologyDalian 116024China Division of Computational and Data Sciences Washington UniversitySt.LouisMO 63130USA

Purpose This scoping review aimed to offer researchers and practitioners an understanding of artificial intelligence(AI)applications in physical activity(PA)interventions;introduce them to prevalent machine learning(ML),deep learning(DL),and reinforcement learning(RL)algorithms;and encourage the adoption of AI *** A scoping review was performed in PubMed,Web of Science,Cochrane Library,and EBSCO focusing on AI applications for promoting PA or predicting related behavioral or health *** methodologies were summarized and categorized to identify synergies,patterns,and trends informing future ***,a concise primer on predominant AI methodologies within the realm of PA was provided to bolster understanding and broader *** The review included 24 studies that met the predetermined eligibility *** models were found effective in detecting significant patterns of PA behavior and associations between specific factors and intervention *** studies comparing AI models to traditional statistical approaches reported higher prediction accuracy for AI models on test *** of different AI models yielded mixed results,likely due to model performance being highly dependent on the dataset and *** increasing trend of adopting state-of-the-art DL and RL models over standard ML was observed,addressing complex human–machine communication,behavior modification,and decision-making *** key areas for future AI adoption in PA interventions emerged:personalized PA interventions,real-time monitoring and adaptation,integration of multimodal data sources,evaluation of intervention effectiveness,expanding access to PA interventions,and predicting and preventing *** The scoping review highlights the potential of AI methodologies for advancing PA *** the field progresses,staying informed and exploring emerging AI-driven strategies is essential for achieving significant improveme

关键词： Artificial intelligence Intervention Machine learning Neural network Physical activity