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Palladium-catalyzed stereoselective decarboxylative[4+2]cyclization of 2-methylidenetrimethylene carbonates with pyrrolidone-derived enones:Straightforward access to chiral tetrahydropyran-fused spiro-pyrrolidine-2,3-diones

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Chinese Chemical Letters 2024年第6期35卷 279-282页

作者： Ke Zhang Sheng zuo Pengyuan You Tong Ru Fen-Er Chen Key Laboratory of Natural Medicines of the Changbai Mountain Ministry of EducationCollege of PharmacyYanbian UniversityYanji 133002China College of Chemistry and Chemical Engineering Jiangxi Normal UniversityNanchang 330022China Engineering Center of Catalysis and Synthesis for Chiral Molecules Fudan UniversityShanghai 200433China Shanghai Engineering Center of Industrial Catalysis for Chiral Drugs Shanghai 200433China

A novel asymmetric[4+2]cycloaddition of 2-methylidenetrimethylene carbonate with pyrrolidonederived enones has been achieved to produce the functionalized tetrahydropyran-fused spirocyclic scaffolds via *** array of enantioenriched spiro-pyrrolidine-2,3-diones bearing adjacent quaternary and tertiary stereocenters are obtained in high yields with excellent enantioselectivities(up to 96% yield and 99% ee).The further transformation of the product has been accomplished for the construction of medical interesting β^(2,2)-amino acids and β-*** mechanistic research was well conducted.

关键词： Pyrrolidine-2,3-diones 2-Methylidenetrimethylene carbonate Asymmetric annulation Spiroheterocycles Allylic 1,3-strain

Fractal model of spontaneous imbibition in low-permeability reservoirs coupled with heterogeneity of pore seepage channels and threshold pressure

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Petroleum Science 2024年第2期21卷 1002-1017页

作者： Ming-Sheng zuo Hao Chen Xi-Liang Liu Hai-Peng Liu Yi Wu Xin-Yu Qi National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China College of Safety and Ocean Engineering China University of Petroleum(Beijing)Beijing102249China

Spontaneous imbibition(SI)is an important mechanism for enhancing oil recovery in low-permeability *** to the strong heterogeneity,and the non-Darcy flow,the construction of SI model for lowpermeability reservoirs is extremely ***,traditional SI models based on single or averaged capillary tortuosity ignore the influence of heterogeneity of pore seepage channels and the threshold pressure(TP)on ***,in this work,based on capillary model and fractal theory,a mathematical model of characterizing SI considering heterogeneity of pore seepage channels is *** this basis,the threshold pressure was introduced to determine the pore radius at which the wetted phase can displace *** proposed new SI model was verified by imbibition experimental *** study shows that for weakly heterogeneous cores with permeability of 0-1 m D,the traditional SI model can characterize the imbibition process relatively accurately,and the new imbibition model can increase the coefficient of determination by 1.05 ***,traditional model has serious deviations in predicting the imbibition recovery for cores with permeability of 10-50 m *** new SI model coupling with heterogeneity of pore seepage channels and threshold pressure effectively solves this problem,and the determination coefficient is increased from 0.344 to 0.922,which is increased by2.68 *** low-permeability reservoirs,the production of the oil in transitional pores(0.01-0.1μm)and mesopores(0.1-1μm)significantly affects the imbibition recovery,as the research shows that when the heterogeneity of pore seepage channels is ignored,the oil recovery in transitional pores and mesopores decreases by 7.54%and 4.26%,*** analysis shows that increasing interfacial tension,decreasing contact angle,oil-water viscosity ratio and threshold pressure will increase imbibition *** addition,there are critical values for the influence of these factors o

关键词： Spontaneous imbibition Low-permeability reservoir Fractal model Threshold pressure Capillary tube

Air pressure law of a reservoir constructed in karst sinkholes

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Journal of Mountain Science 2024年第3期21卷 1048-1057页

作者： YU Bo TAI Shengping ZHENG Kexun CHEN Shiwan HAN Xiao WANG Senlin zuo Shuangying Power China Guiyang Engineering Corporation Limited Guiyang 550081China College of Resources and Environmental Engineering Key Laboratory of Karst Georesources and EnvironmentMinistry of EducationGuizhou UniversityGuiyang 550025China

Karst sinkholes with natural negative landform provide favorable conditions for the pumped storage reservoir construction for less excavation ***,the construction of the reservoir would plug the natural karst channels for water and air,which would cause remarkable air pressure in karst channels when the groundwater level fluctuates.A large laboratory simulation test was carried out to study the air pressure variation of a reservoir built on the karst *** air pressure in the karst channel and inside the model was monitored during the groundwater rising and falling *** showed that the variation of air pressure in the karst channel and the surrounding rock exhibited a high degree of *** air pressure increased rapidly at the initial stage of water level rising,followed by a slight decrease,then the air pressure increased sharply when the water level approached the top of the karst *** initial peak of air pressure and the final peak of air pressure were defined,and both air pressure peaks were linearly increasing with the water level rising *** negative air pressure was also analyzed during the drainage process,which was linearly correlated with the water level falling *** causes of air pressure variation in karst channels of a pumped storage reservoir built on the karst sinkhole were *** initial rapid increase,then slight decrease and final sudden increase of air pressure were controlled by the combined effects of air compression in karst channel and air seepage into the surrounding *** the drainage process,the instant negative air pressure and gradual recovering of air pressure were controlled by the combined effects of negative air pressure induced by water level falling and air supply from surrounding *** work could provide valuable reference for the reservoir construction in karst area.

关键词： Simulation test Karst sinkhole Pumped storage reservoir Air pressure Flow rate

Revealing the intrinsic mechanisms for accelerating nitrogen removal efficiency in the Anammox reactor by adding Fe(Ⅱ)at low temperature

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Chinese Chemical Letters 2024年第8期35卷 341-348页

作者： Linjing Li Wenlai Xu Jianyong Ning Yaping Zhong Chuyue Zhang Jiane zuo Zhicheng Pan State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu 610059China State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China National Postdoctoral Research Station Haitian Water GroupChengdu 610213China National Enterprise Technology Center Haitian Water GroupChengdu 610213China Water Safety and Water Pollution Control Engineering Technology Research Center in Sichuan Province Chengdu 610213China Laboratory of Municipal Wastewater Treatment Technology in Sichuan Province Chengdu 610213China Institute of Environment and Ecology Tsinghua Shenzhen International Graduate SchoolShenzhen 518055China

Fe(Ⅱ)is an essential trace element for anaerobic ammonium oxidation bacteria(AAOB)metabolism,and can improve the nitrogen removal efficiency of anaerobic ammonia oxidation(Anammox).Here we oper-ated two identical expanded granular sludge bed(EGSB)reactors at low temperature(15±3℃)for 154 *** 1(R_(1))received additional Fe(Ⅱ)(0.12 mmol/L)during the late startup phase,while reactor 0(R_(0))served as the control and did not receive extra Fe(Ⅱ).Nitrogen removal in R_(1)became stable at 55 d of operation,ten days earlier than R_(0).The nitrogen removal rate(NRR)of R_(1) was 1.64 kg N m^(−3)d^(−1)and its TN removal rate was as high as 89%,while R_(0)only reached 75%.The addition of Fe(Ⅱ)was fur-ther beneficial to aggregation and stability of the granular sludge,and the used sludge of both reactors showed enrichment for AAOB populations compared to the inoculum,for instance,increased abundance of Candidatus-Kuenenia and in particular of Candidatus-Brocadia(from 0.17%to 10.10%in R_(0)and 7.79%in R_(1)).Diverse microbial species and complex microbial network structure in R_(1)compared to R_(0)promoted the coupled denitrogenation by Anammox,dissimilatory nitrate reduction to ammonium(DNRA),nitrate-dependent Fe oxidation(NDFO),and ferric ammonium oxidation(Feammox).In addition,the microbial community in R_(1)was more resistant to short-term low temperature(2-7℃)starvation,illustrating a further positive effect of adding Fe(Ⅱ)during the startup phase of an Anammox reactor.

关键词： Ambient low temperature Anammox Fe(Ⅱ) Extracellular polymeric substances Microbial community Microbial network analysis

Study on the optimal incident proton energy of ^(7)Li(p,n)^(7)Be neutron source for boron neutron capture therapy

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Nuclear Science and Techniques 2024年第3期35卷 170-180页

作者： Yi-Nan Zhu zuo-Kang Lin Hai-Yan Yu Ye Dai Zhi-Min Dai Xiao-Han Yu Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Science Beijing 100049China

Boron neutron capture therapy(BNCT)is recognized as a precise binary targeted radiotherapy technique that effectively eliminates tumors through the^(10)B(n,α)^(7)Li nuclear *** various neutron sources,accelerator-based sources have emerged as particularly promising for BNCT ***^(7)Li(p,n)^(7)Be reaction is highly regarded as a potential neutron source for BNCT,owing to its low threshold energy for the reaction,significant neutron yield,appropriate average neutron energy,and additional *** study utilized Monte Carlo simulations to model the physical interactions within a lithium target subjected to proton bombardment,including neutron moderation by an MgF_(2)moderator and subsequent BNCT dose analysis using a Snyder head *** study focused on calculating the yields of epithermal neutrons for various incident proton energies,finding an optimal energy at 2.7 ***,the Snyder head phantom was employed in dose simulations to validate the effectiveness of this specific incident energy when utilizing a^(7)Li(p,n)^(7)Be neutron source for BNCT purposes.

关键词： Boron neutron capture therapy ^(7)Li(p,n)7Be neutron source Incident proton energy Monte Carlo simulation

Recent advances and practical challenges of high-energy-density flexible lithium-ion batteries

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Frontiers of Chemical Science and Engineering 2024年第8期18卷 79-98页

作者： Guangxiang Zhang Xin Chen Yulin Ma Hua Huo Pengjian zuo Geping Yin Yunzhi Gao Chuankai Fu State Key Laboratory of Space Power-Sources Harbin Institute of TechnologyHarbin 150001China MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage School of Chemistry and Chemical EngineeringHarbin Institute of TechnologyHarbin 150001China

With the rapid iteration and update of wearable flexible devices,high-energy-density flexible lithium-ion batteries are rapidly ***,energy density,and safety are all important indicators for flexible lithium-ion batteries,which can be determined jointly by material selection and structural ***,recent progress on high-energy-density electrode materials and flexible structure designs are *** electrode materials and the next-generation high-energy-density electrode materials are analyzed in *** electrolytes with high safety and excellent flexibility are classified and *** strategies to increase the mass loading of active materials on the electrodes by designing the current collector and electrode structure are discussed with keys of representative *** the novel configuration structures to enhance the flexibility of batteries are *** the end,it is pointed out that it is necessary to quantify the comprehensive performance of flexible lithium-ion batteries and simultaneously enhance the energy density,flexibility,and safety of batteries for the development of the next-generation high-energy-density flexible lithium-ion batteries.

关键词： lithium-ion batteries flexibility high energy density safety

Explainable artificial intelligence models for mineral prospectivity mapping

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Science China Earth Sciences 2024年第9期67卷 2864-2875页

作者： Renguang zuo Qiuming CHENG Ying XU Fanfan YANG Yihui XIONG Ziye WANG Oliver P.KREUZER State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan 430074China School of Earth Sciences and Engineering Sun Yat-sen UniversityZhuhai 519000China Corporate Geoscience Group(CGSG) PO Box 5128 Rockingham BeachWA 6969Australia Economic Geology Research Centre(EGRU) College of Science and EngineeringJames Cook UniversityTownsvilleQLD 4811Australia

Mineral prospectivity mapping(MPM)is designed to reduce the exploration search space by combining and analyzing geological prospecting big *** geological big data are too large and complex for humans to effectively handle and *** intelligence(AI)algorithms,which are powerful tools for mining nonlinear mineralization patterns in big data obtained from mineral exploration,have demonstrated excellent performance in ***,AI-driven MPM faces several challenges,including difficult interpretability,poor generalizability,and physical *** this study,based on previous studies,we devised a novel workflow that aims to constructing more transparent and explainable artificial intelligence(XAI)models for MPM by embedding domain knowledge throughout the AI-driven MPM,from input data to model design and model *** newly proposed approach provides strong geological and conceptual leads that guide the entire AI-driven MPM model training process,thereby improving model interpretability and ***,the development of XAI models for MPM is capable of embedding prior and expert knowledge throughout the modeling process,presenting a valuable and promising area for future research designed to improve MPM.

关键词： Artificial intelligence Mineral prospectivity mapping Geological prospecting big data Domain knowledge Interpretability

Upcycling electroplating sludge into bioengineering-enabled highly stable dual-site Fe-Ni_(2)P@C electrocatalysts for efficient oxygen evolution

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Nano Research 2024年第8期17卷 6984-6992页

作者： Jiawen Liu Zunpeng zuo Feng Gao Kai Yi Jiahui Lin Mengye Wang Zhang Lin Feng Huang State Key Laboratory of Optoelectronic Materials and Technologies School of MaterialsSun Yat-Sen UniversityGuangzhou 510275China Department of Chemistry City University of Hong KongHong Kong 999077China School of Metallurgy and Environment Central South UniversityChangsha 410083China Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou 341000China

The advancement of bimetallic catalysts holds significant promise for the innovation of oxygen evolution reaction(OER)*** from adsorbate evolution mechanism(AEM)and lattice oxygen oxidation mechanism(LOM),the incorporation of dual active sites has the potential to foster novel OER pathways,such as the coupled oxygen evolution mechanism(COM),which can surpass the limitations of OER and elevate catalytic *** this study,uniformly distributed Fe/Ni dual-site Fe-Ni_(2)P@C electrocatalysts are crafted by upcycling metals in electroplating sludge via an eco-friendly and sustainable microbial engineering *** findings indicate that a substantial number of defects emerge at the Ni2P crystal during the OER process,laying the groundwork for lattice oxygen ***,the displacement of Ni/Fe in the crystal lattice intensifies the asymmetry of the electronic structure at the metal active sites,facilitating the deprotonation *** research introduces an innovative paradigm for the synthesis of effective and robust transition metal-based OER catalysts,with implications for sustainable energy generation technologies.

关键词： oxygen evolution reaction dual active sites adsorbate evolution mechanism lattice oxygen mechanism bioengineering

Brain-inspired dual-pathway neural network architecture and its generalization analysis

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Science China(Technological Sciences) 2024年第8期67卷 2319-2330页

作者： DONG SongLin TAN ChengLi zuo ZhenTao HE YuHang GONG YiHong ZHOU TianGang LIU JunMin ZHANG JiangShe College of Artiﬁcial Intelligence Xi’an Jiaotong UniversityXi’an 710049China School of Mathematics and Statistics Xi’an Jiaotong UniversityXi’an 710049China State Key Laboratory of Brain and Cognitive Science Institute of BiophysicsChinese Academy of SciencesBeijing 100101China Institute of Artiﬁcial Intelligence Hefei Comprehensive National Science CenterHefei 230088China University of Chinese Academy of Sciences Beijing 100049China

In this study, we explored the neural mechanism of global topological perception in the human visual system. We showed strong evidence that the retinotectal pathway in the archicortex of the human brain is responsible for global topological perception, and for modulating the local feature processing in the classical ventral visual pathway. Inspired by this recent cognitive discovery,we developed a novel CogNet architecture to emulate the global-local dichotomy of human visual cognitive mechanisms. The thorough experimental results indicate that the proposed CogNet not only significantly improves image classification accuracies but also effectively addresses the texture bias problem observed in baseline CNN models. We have also conducted mathematical analysis for the generalization gap for general neural networks. Our theoretical derivations suggest that the Hurst parameter, a measure of the curvature of the loss landscape, can closely bind the generalization gap. A larger Hurst parameter corresponds to a better generalization ability. We found that our proposed CogNet achieves a lower test error and attains a larger Hurst parameter,strengthening its superiority over the baseline CNN models further.

关键词： global topological perception dual-pathway generalization gap analysis Hurst parameter