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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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One-step construction of strongly coupled Co_(3)V_(2)O_(8)/Co_(3)O_(4)/MXene heterostructure via in-situ Co-F bonds for high performance all-solid-state asymmetric supercapacitors

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Rare Metals 2024年第2期43卷 682-691页

作者： ji Zhou Bin-Bin Liu Hu Zheng Wen-Qing Ma Qian Li Cai-Xia xu Institute for Advanced Interdisciplinary Research(iAIR) Collaborative Innovation Center of Technology and Equipment for Biological Diagnosis and Therapy in Universities of ShandongSchool of Chemistry and Chemical EngineeringUniversity of JinanJinan250022China

Co_(3)V_(2)O_(8)/Co_(3)O_(4)/Ti_(3)C_(2)T_(x) composite was easily synthesized via one-step succinct-operated hydrothermal *** interconnected Co_(3)V_(2)O_(8)/Co_(3)O_(4) nanowires network can in-situ grow and anchor on the surface of Ti_(3)C_(2)T_(x) via the strong Co-F bonds and contribute tremendously to depress Ti_(3)C_(2)T_(x) *** from the synergistically interplayed effect among the multiple interfaces and high conductivity of Ti_(3)C_(2)T_(x) as well as outstanding stability of the as-designed nanostructure,the optimum Co_(3)V_(2)O_(8)/Co_(3)O_(4)/Ti_(3)C_(2)T_(x)electrode reaches a commendable specific capacitance(up to 3800 mF·cm^(−2)),great rate capability(80%capacitance retention after 20-times current increasing),and preeminent cycling stability(95.4%/85.5%retention at 7000th/20,000th cycle).Moreover,the all-solid-state asymmetric supercapacitor based on Co_(3)V_(2)O_(8)/Co_(3)O_(4)/Ti_(3)C_(2)T_(x) and active carbon can deliver a high energy density of 84.0μWh·cm^(−2) at the power energy of 3.2 mW·cm^(−2),and excellent cycling durability with 87.0%of initial capacitance retention upon 20,000 *** work provides a practicable pathway to tailor MXene-based composites for high-performance supercapacitor.

关键词： Ti_(3)C_(2)T_(x) Co_(3)V_(2)O_(8)/Co_(3)O_(4) Heterostructure Cathode Supercapacitor

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Conventional and micro scale finite element modeling for metal cutting process:A review

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Chinese Journal of Aeronautics 2024年第2期37卷 199-232页

作者： Le WANG Caixu YUE Xianli LIU Ming LI Yongshi xu Steven Y.liang Key Laboratory of Advanced Manufacturing and Intelligent Technology Ministry of EducationHarbin University of Science and TechnologyHarbin 150080China George W.Woodruff School of Mechanical Engineering Georgia Institute of TechnologyAtlanta 30332USA

The metal cutting process is accompanied by complex stress field,strain field,temperature *** comprehensive effects of process parameters on chip morphology,cutting force,tool wear and residual stress are complex and *** element method(FEM)is considered as an effective method to predict process variables and reveal microscopic physical phenomena in the cutting ***,the finite element(FE)simulation is used to research the conventional and micro scale cutting process,and the differences in the establishment of process variable FE simulation models are distinguished,thereby improving the accuracy of FE *** reliability and effectiveness of FE simulation model largely depend on the accuracy of the simulation method,constitutive model,friction model,damage model in describing mesh element,the dynamic mechanical behavior of materials,the tool-chip-workpiece contact process and the chip formation *** this paper,the FE models of conventional and micro process variables are comprehensively and up-to-date reviewed for different materials and machining *** purpose is to establish a FE model that is more in line with the real cutting conditions,and to provide the possibility for optimizing the cutting process *** development direction of FE simulation of metal cutting process is discussed,which provides guidance for future cutting process modeling.

关键词： Conventional and micro scale Finite element simulation Metal cutting process Micro cutting Modeling

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Kilometer-resolution three-dimensional crustal deformation of Tibetan Plateau from InSAR and GNSS

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Science China Earth Sciences 2024年第6期67卷 1818-1835页

作者： Chuanjin LIU Lingyun ji liangyu ZHU Caijun xu Chaoying ZHAO Zhong LU Qingliang WANG School of Geodesy and Geomatics Wuhan UniversityWuhan 430079China The Second Monitoring and Application Center China Earthquake AdministrationXi’an 710054China College of Geological Engineering and Geomatics Chang’an UniversityXi’an 710054China Roy M.Huffington Department of Earth Sciences Southern Methodist UniversityDallasTX 75025USA

Located at the forefront of the collision between the Indian and Eurasian Plates,the Tibetan Plateau experiences intense crustal *** ground-based geodetic monitoring,such as GNSS and leveling,is challenging,due to factors such as high altitude and harsh climate,making it difficult to accurately determine a high-resolution crustal deformation field of the *** by ground observation conditions,InSAR technique has key advantages for obtaining extensive and high-resolution crustal deformation *** makes it indispensable for crustal deformation monitoring on the Tibetan *** study used Sentinel-1 data from 2014 to 2020 to compute the ascending and descending InSAR deformation fields for the Tibetan *** was conducted with a measurement accuracy of approximately 3 mm/*** upon this,we integrated InSAR and GNSS data to yield kilometer-resolution three-dimensional(3D)crustal deformation and strain rate fields for the Tibetan Plateau.A spherical wavelet analysis was used to decompose the 3D deformation field and separate the nontectonic crustal deformation to increase the strength of the tectonic deformation ***-wavelength(110 km)deformation mainly results from subsidence in the central plateau and uplifts along the Himalayan *** indicates that the Tibetan Plateau may have stopped the entire uplift and entered a local collapse ***,the deformation fields at different spatial scales reveal that the plateau exhibits discontinuous deformation in short wavelengths and continuous deformation in long *** findings of this study contribute to resolving the controversy between the Block and Continuum Deformation models of the Tibetan Plateau.

关键词： Tibetan Plateau InSAR GNSS 3D Deformation Deformation Model

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Metal-Organic Framework Enabling Poly(Vinylidene Fluoride)-Based Polymer Electrolyte for Dendrite-Free and Long-Lifespan Sodium Metal Batteries

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Energy & Environmental Materials 2024年第1期7卷 72-80页

作者： Yusi Lei liang Yue Yuruo Qi Yubin Niu Shujuan Bao jie Song Maowen xu Faculty of Materials and Energy Institute for Clean Energy & Advanced Materials Southwest University Shandong Zero-One-Four Advanced Materials Co. Ltd.

Sodium dentrite formed by uneven plating/stripping can reduce the utilization of active sodium with poor cyclic stability and,more importantly,cause internal short circuit and lead to thermal runaway and ***,sodium de... 详细信息

关键词： dendrite-free gel polymer electrolyte metal organic framework sodium batteries

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Span-based joint entity and relation extraction augmented with sequence tagging mechanism

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Science China(Information Sciences) 2024年第5期67卷 84-98页

作者： Bin ji Shasha LI Hao xu jie YU Jun MA Huijun LIU jing YANG College of Computer National University of Defense Technology

Span-based joint extraction simultaneously conducts named entity recognition(NER) and relation extraction(RE) in a text span form. However, since previous span-based models rely on span-level classifications, they cannot benefit from token-level label information, which has been proven advantageous for the task. In this paper, we propose a sequence tagging augmented span-based network(STSN), a spanbased joint model that can make use of token-level label information. In STSN, we construct a core neural architecture by deep stacking multiple attention layers, each of which consists of three basic attention *** the one hand, the core architecture enables our model to learn token-level label information via the sequence tagging mechanism and then uses the information in the span-based joint extraction; on the other hand, it establishes a bi-directional information interaction between NER and RE. Experimental results on three benchmark datasets show that STSN consistently outperforms the strongest baselines in terms of F1,creating new state-of-the-art results.

关键词： joint extraction named entity recognition relation extraction span sequence tagging mechanism

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A creep model for ultra-deep salt rock considering thermal-mechanical damage under triaxial stress conditions

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第2期16卷 588-596页

作者： Chao liang jianfeng Liu jianxiong Yang Huining xu Zhaowei Chen Lina Ran College of Water Resource and Hydropower Sichuan UniversityChengdu610065China CNPC Key Laboratory of Oil and Gas Underground Storage Engineering Langfang065007China CNPC Engineering Technology R&D Company Limited Beijing102206China

To investigate the specific creep behavior of ultra-deep buried salt during oil and gas exploitation,a set of triaxial creep experiments was conducted at elevated temperatures with constant axial pressure and unloading confining pressure *** results show that the salt sample deforms more significantly with the increase of applied temperature and deviatoric *** accelerated creep phase is not occurring until the applied temperature reaches 130℃,and higher temperature is beneficial to the occurrence of accelerated *** describe the specific creep behavior,a novel three-dimensional(3D)creep constitutive model is developed that incorporates the thermal and mechanical variables into mechanical ***,the standard particle swarm optimization(SPSO)method is adopted to fit the experimental data,and the sensibility of key model parameters is analyzed to further illustrate the model *** a result,the model can accurately predict the creep behavior of salt under the coupled thermo-mechanical effect in deep-buried *** on the research results,the creep mechanical behavior of wellbore shrinkage is predicted in deep drilling projects crossing salt layer,which has practical implications for deep rock mechanics problems.

关键词： Creep experiments Creep model Thermal and mechanical damage Fractional derivative

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Human activity over natural inputs determines the bacterial community in an ice core from the Muztag ata glacier

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Science China Earth Sciences 2024年第5期67卷 1489-1499页

作者： Yongqin LIU Nianzhi jiAO Mukan ji Keshao LIU Baiqing xu Bixi GUO Tandong YAO State Key Laboratory of Tibetan Plateau Earth System Resources and Environment(TPESRE)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China Center for Pan-third Pole Environment Lanzhou UniversityLanzhou 730013China University of Chinese Academy of Sciences Beijing 100101China State Key Laboratory for Marine Environmental Science Xiamen UniversityXiamen 361102China

Ice core provides a valuable vertical timeline of past climates and anthropogenic *** proxies have been widely used in these studies,but there are few biological indicators *** address this gap,we investigated the bacterial community from a 74 m ice core of Muztag ata glacier on the Tibetan Plateau to link biological indicators with past climate and anthropogenic *** analyzing the portion of the ice core with environmental proxies available(corresponding to 1907 to 1991),we observed an increase in bacterial richness throughout the ice core,which was associated with higher NH_(4)^(+),an indicator of agricultural *** bacterial community was jointly determined by human activity,natural input,and air temperature,with a strong human influence after the ***,the relative abundance of animal gut-associated bacteria,including Aerococcaceae,Nocardiaceae,Muribaculaceae,and Lachnospiraceae,was associated with livestock number changes in the Central Asian *** with other bacterial lineages,they jointly explained 59.8%of the livestock number *** study provides quantitative evidence of the associations between bacterial indicators and past climate and human activities,highlighting the potential of using bacterial proxies for ice core studies.

关键词： Ice core of Muztag ata glacier Climate change and anthropogenic activity Biological indicator Gut-associated bacteria livestock number in the Central Asian region

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A homing rescue gene drive with multiplexed gRNAs reaches high frequency in cage populations but generates functional resistance

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Journal of Genetics and Genomics 2024年第8期51卷 836-843页

作者： Shibo Hou jingheng Chen Ruobing Feng xuejiao xu Nan liang Jackson Champer Center for Bioinformatics Center for Life SciencesSchool of Life SciencesPeking UniversityBeijing 100871China

CRISPR homing gene drives have considerable potential for managing populations of medically and agriculturally significant *** operate by Cas9 cleavage followed by homology-directed repair,copying the drive allele to the wild-type chromosome and thus increasing in frequency and spreading throughout a ***,resistance alleles formed by end-joining repair pose a significant *** address this,we create a homing drive targeting the essential hairy gene in Drosophila *** resistance alleles are recessive lethal,while drive carriers have a recoded“rescue”version of *** drive inheritance rate is moderate,and multigenerational cage studies show drive spread to 96%–97%of the ***,the drive does not reach 100%due to the formation of functional resistance alleles despite using four *** alleles have a large deletion but likely utilize an alternate start ***,revised designs targeting more essential regions of a gene may be necessary to avoid such functional *** of the rescue element’s native 3'UTR with a homolog from another species increases drive inheritance by 13%–24%.This was possibly because of reduced homology between the rescue element and surrounding genomic DNA,which could also be an important design consideration for rescue gene drives.

关键词： Genedrive Homing drive Rescueelement Population modification Multiplexed gRNAs Resistance alleles Cage study

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A Pre-Selection-Based Ant Colony System for Integrated Resources Scheduling Problem at Marine Container Terminal

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Computers, Materials & Continua 2024年第8期80卷 2363-2385页

作者： Rong Wang Xinxin xu Zijia Wang Fei ji Nankun Mu School of Electronic and Information Engineering South China University of TechnologyGuangzhou510641China School of Computer Science and Technology Ocean University of ChinaQingdao266100China School of Computer Science and Cyber Engineering Guangzhou UniversityGuangzhou510006China School of Computer Science Chongqing UniversityChongqing400044China

Marine container terminal(MCT)plays a key role in the marine intelligent transportation system and international logistics ***,the efficiency of resource scheduling significantly influences the operation performance of *** solve the practical resource scheduling problem(RSP)in MCT efficiently,this paper has contributions to both the problem model and the algorithm ***,in the problem model,different from most of the existing studies that only consider scheduling part of the resources in MCT,we propose a unified mathematical model for formulating an integrated *** new integrated RSP model allocates and schedules multiple MCT resources simultaneously by taking the total cost minimization as the ***,in the algorithm design,a pre-selection-based ant colony system(PACS)approach is proposed based on graphic structure solution representation and a pre-selection *** the one hand,as the RSP can be formulated as the shortest path problem on the directed complete graph,the graphic structure is proposed to represent the solution encoding to consider multiple constraints and multiple factors of the RSP,which effectively avoids the generation of infeasible *** the other hand,the pre-selection strategy aims to reduce the computational burden of PACS and to fast obtain a higher-quality *** evaluate the performance of the proposed novel PACS in solving the new integrated RSP model,a set of test cases with different sizes is *** results and comparisons show the effectiveness and efficiency of the PACS algorithm,which can significantly outperform other state-of-the-art algorithms.

关键词： Resource scheduling problem(RSP) ant colony system(ACS) marine container terminal(MCT) pre-selection strategy

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