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highly selective and eco-friendly dihydroisoquinoline synthesis via Cu/Co synergistic catalysis in Cu NPs@MOFs catalyst under mild conditions

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science China Chemistry 2024年第5期67卷 1561-1568页

作者： Peng-Fei Guo ze-Long Liang Yue-e Jiao hang Xu Bin Zhao Key Laboratory of Advanced energy Material Chemistry Renewable Energy Conversion and Storage CenterDepartment of ChemistryNankai UniversityTianjin 300071China

3,4-Dihydroisoquinoline(DhIQ)is an important precursor used in the production of drugs for treating cancer,hIV,Alzheimer's disease,*** studies on DhIQ synthesis show low catalytic selectivity due to the susceptible over-oxidation feedstock of1,2,3,4-tetrahydroisoquinoline(ThIQ),which often requires alkali ***,it is desirable yet challenging to explore a highly selective and efficient oxydehydrogenation capacity for DhIQ synthesis under eco-friendly reaction ***,a novel framework 1 was synthesized,exhibiting 1D channels with the size of 4.6 A×9.6 A and high solvent/p h/thermal stability.A stable framework allows it to encapsulate Cu nanoparticles(NPs)to form Cu NPs@1-x(x=1,2,3,and 4)with varying loading amounts of Cu NPs at 2.0 wt%,3.0 wt%,4.0 wt%,and 6.0 wt%,*** NPs@1-3 could selectively catalyze the reaction from ThIQ to DhIQ with a high selectivity of 98%and a recorded turnover frequency(TOF)of 22.1 h-1under eco-friendly mild *** corresponding catalytic activity can maintain at least five recyclings and can be further applied to gram-scale ***,the efficient preparation of DhIQ catalyzed by Cu NPs@1-3 could be realized even under air ***,the anticancer molecule precursor synthesis of 6,7-dimethoxy-3,4-dihydroisoquinoline was also selectively catalyzed by Cu NPs@*** investigations revealed that high catalytic performance can be attributed to the stable framework and the synergistic catalytic effect of the loaded Cu NPs and Co metal *** importantly,this work represents the first example of MOF catalysts for selectively thermo-catalytic DhIQ synthesis and demonstrates a simple approach to obtain efficient catalysts for selective oxydehydrogenation in the production of unsaturated compounds.

关键词： metal-organic frameworks Cu NPs@MOFs 3 4-dihydroisoquinoline selective oxydehydrogenation synergistic catalysis

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Robustness of the octupole collectivity in 144Ba within the cranking covariant density functional theory in 3D lattice

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Nuclear science and Techniques 2024年第8期35卷 124-131页

作者： ze‑Kai Li Yuan‑Yuan Wang Mathematics and Physics Department North China Electric Power UniversityBeijing 102206China hebei Key Laboratory of Physics and energy Technology North China Electric Power UniversityBaoding 071000China

The octupole deformation and collectivity in octupole double-magic nucleus 144Ba are investigated using the Cranking covariant density functional theory in a three-dimensional lattice *** reduced B(e3)transition probability is implemented for the first time in semiclassical approximation based on the microscopically calculated electric octupole *** available data,including the I-ωrelation and electric transitional probabilities B(e2)and B(e3)are well ***,it is shown that the ground state of 144Ba exhibits axial octupole and quadrupole deformations that persist up to high spins(I≈24h).

关键词： Octupole collectivity Cranking covariant density functional theory Rotational spectrum electric transitional probabilities

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hall Algebras and Quantum symmetric Pairs of Kac-Moody Type Ⅱ

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Acta Mathematica sinica,english series 2024年第3期40卷 806-822页

作者： Ming LU Run ze shANG Department of Mathematics Sichuan UniversityChengdu 610064P.R.China

We extend the ■hall algebra realization of ■quantum groups arising from quantum symmetric pairs,which establishes an injective homomorphism from the universal ■quantum group of Kac-Moody type to the ■hall algebra ... 详细信息

关键词： Quantum symmetric pairs hall algebras Quiver with involutions

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One-pot synthesis of hierarchical Flower-like Ws_(2) Microspheres as Anode Materials for Lithium-ion Batteries

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Journal of Wuhan University of Technology(Materials science) 2024年第1期39卷 1-6页

作者：张向华 TAN hen WANG ze XUe Maoquan school of Mechanical engineering Jiangsu University of TechnologyChangzhou 213001China school of Materials engineering Jiangsu University of TechnologyChangzhou 213001China Changzhou Vocational Institute of Industry Technology Changzhou 213164China

3D hierarchical flowerlike Ws_(2) microspheres were synthesized through a facile one-pot hydrothermal *** as-synthesized samples were characterized by powder X-ray powder diffraction (XRD),energy-dispersive spectroscopy (eDs),scanning electron microscopy (seM) and *** images of the samples reveal that the hierarchical flowerlike Ws_(2) microspheres with diameters of about 3-5μm are composed of a number of curled *** tests such as charge/discharge,cyclic voltammetry,cycle life and rate performance were carried out on the Ws_(2) *** an anode material for lithium-ion batteries,hierarchical flowerlike Ws_(2) microspheres show excellent electrochemical *** a current density of100 mA·g^(-1),a high specific capacity of 647.8 mA·h·g^(-1) was achieved after 120 discharge/charge *** excellent electrochemical performance of Ws_(2) as an anode material for lithium-ion batteries can be attributed to its special 3D hierarchical structure.

关键词： Ws_(2) microspheres lithium-ion batteries electrochemical performance

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A methodology for laser tool setters calibration and its precise mathematical model

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Chinese Journal of Aeronautics 2024年第7期37卷 564-581页

作者： Tao FANG Zixi FANG ze Zhong CheN Zhiyong ChANG school of Mechanical engineering Northwestern Polytechnical UniversityXi’an 710072China Gina Cody school of engineering and Computer science Concordia UniversityMontrealQuebec H3G 1M8Canada Changsha Optimum CNC Corporation Changsha 410221China Institute for Aero-engine smart Assembly of shaanxi Province Xi’an 710072China

On-machine tool setting is a pivotal approach in achieving intelligent manufacturing,and laser tool setters have become a crucial component of smart machine *** tool setters play a crucial role in precisely measuring the dimensions of cutting tools during the part machining process,focusing on tool length and *** a measuring instrument,the positions of the laser axis of the laser tool setter need to be accurately calibrated before ***,in actual calibration scenarios,traditional calibration methods face challenges due to installation errors in the tool setter and geometric errors in the measuring *** address this issue,this study proposes a novel calibration ***,the calibration mechanism of the laser beam axis is *** on the accurate mathematical model of the laser beam and the measuring rod,and using the polygon clipping algorithm,the mathematical mechanism of the laser tool setter’s work is ***,a novel method is introduced to calculate the compensation distance between the laser beam reference point and the rod bottom center point at each moment during ***,by utilizing the kinematic chain of the tool setter calibration system,a new calibration method is developed to accurately calibrate the position of the laser beam axis in the machine tool coordinate ***,the accuracy of the calibration method is verified through simulation experiments and calibration *** method improves the calibration accuracy of the tool setter,and the mathematical model of the laser tool setter can be extended to the measurement of tools,thereby improving the precision of tool *** research significantly improves the efficient production performance of smart machine tools.

关键词： On-machine tool setting smart machine tools Mathematical model Calibration method Laser tool sette

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Benchmarking visual sLAM methods in mirror environments

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Computational Visual Media 2024年第2期10卷 215-241页

作者： Peter herbert Jing Wu ze Ji Yu-Kun Lai school of Computer science and Informatics Cardiff UniversityAbacws BuildingSenghennydd RdCardiff CF244AGUK school of engineering Cardiff UniversityQueen’s BuildingsThe ParadeCardiff CF243AAUK

Visual simultaneous localisation and mapping(vsLAM)finds applications for indoor and outdoor navigation that routinely subjects it to visual complexities,particularly mirror *** effect of mirror presence(time visible and its average size in the frame)was hypothesised to impact localisation and mapping performance,with systems using direct techniques expected to perform ***,a dataset,Mirrenv,of image sequences recorded in mirror environments,was collected,and used to evaluate the performance of existing representative *** ORB-sLAM3 and BundleFusion appear to show moderate degradation of absolute trajectory error with increasing mirror duration,whilst the remaining results did not show significantly degraded localisation *** mesh maps generated proved to be very inaccurate,with real and virtual reflections colliding in the reconstructions.A discussion is given of the likely sources of error and robustness in mirror environments,outlining future directions for validating and improving vsLAM performance in the presence of planar *** Mirrenv dataset is available at https://***/10.17035/d.2023.0292477898.

关键词： visual simultaneous localisation and mapping(vsLAM) mirror localisation mapping reflection datase

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Micro defects formation and dynamic response analysis of steel plate of quasi-cracking area subjected to explosive load

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Defence Technology（防务技术） 2024年第1期31卷 580-593页

作者： Zheng-qing Zhou ze-chen Du Xiao Wang hui-ling Jiang Qiang Zhou Yu-long Zhang Yu-zhe Liu Pei-ze Zhang Research Institute of Macro-safety science University of Science and TechnologyBeijing100083China school of Civil and Resource engineering University of Science and Technology BeijingBeijing100083China school of Mechanical engineering Nantong UniversityNantong226019China China North Industry Advanced Technology Generalization Institute Beijing100089China China Academy of Ordnance science China

As the protective component,steel plate had attracted extensive attention because of frequently threats of explosive *** this paper,the evolution of microstructure and the mechanism of damage in the quasi-cracking area of steel plate subjected to explosive load were discussed and the relationships between micro defects and dynamic mechanical response were *** the explosion experiment,five observation points were selected equidistant from the quasi-cracking area of the section of the steel plate along the thickness direction,and the characteristics of micro defects at the observation points were analyzed by optical microscope(OM),scanning electron microscope(seM) and electron backscattered diffraction(eBsD).The observation result shows that many slip bands(sBs) appeared,and the grain orientation changed obviously in the steel plate,the two were the main damage types of micro *** addition,cracks,peeling pits,grooves and other lager micro defects were appeared in the lower area of the *** stress parameters of the observation points were obtained through an effective numerical *** mechanism of damage generation and crack propagation in the quasicracking area were clarified by comparing the specific impulse of each observation point with the corresponding micro *** result shows that the generation and expansion of micro defects are related to the stress area(*** upper compression area,the neutral plane area,and the lower tension area).The micro defects gather and expand at the grain boundary,and will become macroscopic damage under the continuous action of tensile ***,the micro defects at the midpoint of the section of the steel plate in the direction away from the explosion center(*** horizontal direction) were also *** was found that the specific impulse at these positions were much smaller than that in the thickness direction,the micro defects were only sBs and a few micro cracks,and the those decrea

关键词： explosive load Quasi-cracking area Micro defects steel plate Dynamic response Numerical simulation

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Melt flow,heat transfer and solidification in a flexible thin slab continuous casting mold with vertical-combined electromagnetic braking

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Journal of Iron and steel Research International 2024年第2期31卷 401-415页

作者： Lin Xu ze-feng han Christian Karcher en-gang Wang Key Laboratory of electromagnetic Processing of Materials(Ministry of education) Northeastern UniversityShenyang110819LiaoningChina Key Laboratory of Liaoning Province for Clean Combustion Power Generation and heating Technology Shenyang Institute of EngineeringShenyang110136LiaoningChina Institute of Thermodynamics and Fluid Mechanics Technische Universität IlmenauIlmenau98684Germany

During continuous casting of steel slabs,the application of electromagnetic braking technology(eMBr)provides an effective tool to influence solidification by controlling the pattern of melt flow in the ***,the quality of the final product can be improved considerably.A new electromagnetic braking(eMBr)method,named vertical-combined electromagnetic braking(VC-eMBr),is proposed to be applied to a flexible thin slab casting(FTsC)*** evaluate the beneficial effects of the VC-eMBr,the melt flow,heat transfer,and solidification processes in the FTsC mold are studied by means of numerical *** detail,a Reynolds-averaged Navier–stokes turbulence model together with an enthalpy-porosity approach was *** numerical findings are compared with respective simulations using the traditional *** results demonstrate that the application of the VC-eMBr contributes significantly to preventing relative slab *** contrast to the Ruler-eMBr,the additional vertical magnetic poles of the VC-eMBr preferentially suppress the direct impact of jet flow on the narrow face of FsTC mold and considerably diminish the level fluctuation near the meniscus *** instance,by applying a magnetic flux density of 0.3 T,the maximum amplitude of meniscus deflection reduces by about 80%.Moreover,the braking effect of the VC-eMBr effectively improves the homogeneity of temperature distribution in the upper recirculation region and increases the solidified shell thickness along the casting *** this basis,the newly proposed VC-eMBr shows a beneficial effect in preventing relative slab defects for FTsC thin slab continuous casting.

关键词： electromagnetic braking Mold Melt flow heat transfer solidification

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elevational and temporal patterns of pollination success in distylous and homostylous buckwheats(Fagopyrum)in the hengduan Mountains

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Plant Diversity 2024年第5期46卷 661-670页

作者： Ling-Yun Wu shuang-Quan huang ze-Yu Tong Faculty of Resources and environmental science Hubei UniversityWuhan 430062China Institute of evolution and ecology School of Life SciencesCentral China Normal UniversityWuhan 430079China

Reproductive strategies of sexually dimorphic plants vary in response to the ***,we ask whether the sexual systems of Fagopyrum species(i.e.,selfing homostylous and out-crossing distylous)represent distinct adaptive strategies to increase reproductive success in changing alpine *** answer this question,we determined how spatial and temporal factors(e.g.,elevation and peak flowering time)affect reproductive success(i.e.,stigmatic pollen load)in nine wild Fagopyrum species(seven distylous and two homostylous)among 28 populations along an elevation gradient of 1299-3315 m in the hengduan Mountains,southwestern *** also observed pollinators and conducted hundreds of hand pollinations to investigate inter/intra-morph compatibility,self-compatibility and pollen limitation in four Fagopyrum species(two distylous and two homostylous).We found that Fagopyrum species at higher elevation generally had bigger flowers and more stigmatic pollen loads;lateflowering individuals had smaller flowers and lower pollen *** pollen deposition was more variable in distylous species than in homostylous *** seed set was not pollenlimited in all species,we found that fruit set was much lower in distylous species,which rely on frequent pollinator visits,than in homostylous species capable of autonomous *** findings that pollination success increases at high elevations and decreases during the flowering season suggest that distylous and homostylous species have spatially and temporally distinct reproductive strategies related to environment-dependent pollinator activity.

关键词： Biodiversity hotspot elevation gradient Fagopyrum stigmatic pollen load Temporal pattern

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Multiscale spatiotemporal meteorological drought prediction:A deep learning approach

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Advances in Climate Change Research 2024年第2期15卷 211-221页

作者： Jia-Li ZhANG Xiao-Meng hUANG Yu-ze sUN Department of earth system science Ministry of Education Key Laboratory for Earth System ModellingInstitute for Global Change StudiesTsinghua UniversityBeijing 100084China

Reliable monitoring and thorough spatiotemporal prediction of meteorological drought are crucial for early warning and decision-making regarding drought-related *** utilisation of multiscale methods is effective for a comprehensive evaluation of drought occurrence and progression,given the complex nature of meteorological ***,the nonlinear spatiotemporal features of meteorological droughts,influenced by various climatological,physical and environmental factors,pose significant challenges to integrated prediction that considers multiple indicators and time *** address these constraints,we introduce an innovative deep learning framework based on the shifted window transformer,designed for executing spatiotemporal prediction of meteorological drought across multiple *** formulate four prediction indicators using the standardized precipitation index and the standard precipitation evaporation index as core methods for drought definition using the eRA5 reanalysis *** indicators span time scales of approximately 30 d and one ***-term indicators capture more anomalous variations,whereas long-term indicators attain comparatively higher accuracy in predicting future *** focus on the east Asian region,notable for its diverse climate conditions and intricate terrains,to validate the model's efficacy in addressing the complexities of nonlinear spatiotemporal *** model's performance is evaluated from diverse spatiotemporal viewpoints,and practical application values are analysed by representative drought *** results substantiate the effectiveness of our proposed model in providing accurate multiscale predictions and capturing the spatiotemporal evolution characteristics of *** of the four drought indicators accurately delineates specific facets of the meteorological drought ***,three representative drought events,namely flash drought,sustained drought and severe drought,

关键词： Meteorological drought spatiotemporal prediction Multiscale swim transformer Deep learning

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