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Interpretation and characterization of rate of penetration intelligent prediction model

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Petroleum Science 2024年第1期21卷 582-596页

作者： Zhi-Jun Pei Xian-Zhi song Hai-tao Wang Yi-qi Shi Shou-Ceng Tian Gen-Sheng Li College of Petroleum Engineering China University of Petroleum(Beijing)Beijing102249China State Key Laboratory of Petroleum Resources and Prospecting Beijing102249China Kunlun Digital Technology Co. Ltd.Beijing102206China

Accurate prediction of the rate of penetration(ROP)is significant for drilling *** the intelligent ROP prediction model based on fully connected neural networks(FNN)outperforms traditional ROP equations and machine learning algorithms,its lack of interpretability undermines its *** study proposes a novel interpretation and characterization method for the FNN ROP prediction model using the Rectified Linear Unit(ReLU)activation *** leveraging the derivative of the ReLU function,the FNN function calculation process is transformed into vector *** FNN model is linearly characterized through further simplification,enabling its interpretation and *** proposed method is applied in ROP prediction scenarios using drilling data from three vertical wells in the Tarim *** results demonstrate that the FNN ROP prediction model with ReLU as the activation function performs exceptionally *** relative activation frequency curve of hidden layer neurons aids in analyzing the overfitting of the FNN ROP model and determining drilling data *** the well sections with similar drilling data,averaging the weight parameters enables linear characterization of the FNN ROP prediction model,leading to the establishment of a corresponding linear representation ***,the quantitative analysis of each feature's influence on ROP facilitates the proposal of drilling parameter optimization schemes for the current well *** established linear characterization equation exhibits high precision,strong stability,and adaptability through the application and validation across multiple well sections.

关键词： Fully connected neural network Explainable artificial intelligence Rate of penetration ReLU active function Deep learning Machine learning

ANALYSIS OF THE IMPLICIT-EXPLICIT ULTRA-WEAK DISCONTINUOUS GALERKIN METHOD FOR CONVECTION-DIFFUSION PROBLEMS

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Journal of Computational Mathematics 2024年第1期42卷 1-23页

作者： Haijin Wang Anping Xu qi tao School of Science Nanjing University of Posts and TelecommunicationsNanjing 210023China Beijing Computational Science Research Center Beijing 100193China

In this paper,we first present the optimal error estimates of the semi-discrete ultra-weak discontinuous Galerkin method for solving one-dimensional linear convection-diffusion ***,coupling with a kind of Runge-Kutta type implicit-explicit time discretization which treats the convection term explicitly and the diffusion term implicitly,we analyze the stability and error estimates of the corresponding fully discrete *** fully discrete schemes are proved to be stable if the time-stepτ≤τ0,whereτ0 is a constant independent of the mesh-size ***,by the aid of a special projection and a careful estimate for the convection term,the optimal error estimate is also obtained for the third order fully discrete *** experiments are displayed to verify the theoretical results.

关键词： The ultra-weak discontinuous Galerkin method Convection-diffusion Implicitexplicit time discretization Stability Error estimate

Impacts of proppant distribution on development of tight oil reservoirs with threshold pressure gradient

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Petroleum Science 2024年第1期21卷 445-457页

作者： Ming Yue Wei-Yao Zhu Fei-Fei Gou Tian-Ru song Yu-Chun You qi-tao Zhang State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development Beijing102206China School of Civil and Resource Engineering University of Science and Technology BeijingBeijing100083China

Field evidence indicates that proppant distribution and threshold pressure gradient have great impacts on well *** at the development of unconventional oil reservoirs in Triassic Chang-7 Unit,Ordos Basin of China,we presented an integrated workflow to investigate how(1)proppant placement in induced fracture and(2)non-linear flow in reservoir matrix would affect well productivity and fluid flow in the *** with our research before(Yue et al.,2020),here we extended this study into the development of multi-stage fractured horizontal wells(MFHWs)with large-scale complicated fracture *** integrated workflow is based on the finite element method and consists of simulation models for proppant-laden fluid flow,fracture flow,and non-linear seepage flow,*** results indicate that the distribution of proppant inside the induced cracks significantly affects the productivity of the *** we assign an idealized proppant distribution instead of the real distribution,there will be an overestimation of 44.98%in daily oil rate and 30.63%in cumulative oil production after continuous development of 1000 ***,threshold pressure gradient(TPG)also significantly affects the well performance in tight oil *** we simply apply linear Darcy’s law to the reservoir matrix,the overall cumulative oil production can be overrated by 77%after 1000 days of *** general,this research provides new insights into the development of tight oil reservoirs with TPG and meanwhile reveals the significance of proppant distribution and non-linear fluid flow in the production scenario design.

关键词： Proppant distribution Tight oil reservoir Multi-stage fractured horizontal well Threshold pressure gradient Moving boundary

A new liquid membrane diffusion model for characterizing the adsorption kinetics of europium by using a continuous measurement of adsorption platform

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Nuclear Science and Techniques 2024年第1期35卷 59-72页

作者： Hao-qi Yu tao Yu Jian-Hua Ye State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China CGN Cangnan Nuclear Power Co. Ltd.Cangnan 325800China Jiangxi Province Key Laboratory of Polymer Micro/Nano Manufacturing and Devices East China University of TechnologyNanchang 330013China School of Nuclear Science and Engineering East China University of TechnologyNanchang 330013China

To explore the kinetic adsorption under continuous and nonequilibrium states, an integration of continuous measurement and adsorption platform kinetics method was proposed, which was initially called the ICM-AP kinetics method, and a corresponding kinetic adsorption experimental method was developed. Adsorption experiments of europium(Eu) on Ca-bentonite,Na-bentonite, and the D231 cation exchange resin were performed using the ICM-AP kinetics method and continuous measurements. Because the kinetic experimental results observed in this study were different from those of traditional batch adsorption data, pseudo-first-order or pseudo-second-order kinetic models were unsuitable for fitting the experimental ***, a liquid membrane diffusion(LMD) model was developed based on the assumption of simultaneous adsorption/desorption to discuss the mechanism of kinetic adsorption. The kinetic adsorption mechanism was also studied by using *** results indicated that the proposed adsorption model can fit the experimental data more suitably, and the adsorption/desorption behaviors of Eu on bentonite and the D231 resin were simultaneously observed, suggesting that the adsorption kinetics of Eu(Ⅲ) was mainly dominated by hydrated Eu(Ⅲ) ions on the liquid membrane.

关键词： ICM-AP method LMD model Adsorption mechanism Eu(Ⅲ)

A systematic COSMO-RS study on mutual solubility of ionic liquids and C6-hydrocarbons

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Green Chemical Engineering 2024年第1期5卷 97-107页

作者： Chuxin qi Zhen song Hongye Cheng Lifang Chen Zhiwen qi State Key Laboratory of Chemical Engineering School of Chemical EngineeringEast China University of Science and Technology130 Meilong RoadShanghai200237China

When considering the usage of ionic liquids(ILs)for reactions and separations involving non-polar or weak-polar hydrocarbons,the knowledge of the mutual solubility behaviors of ILs and hydrocarbons is of the utmost *** this work,taking four typical C6-hydrocarbons namely benzene,cyclohexene,cyclohexane,and hexane as representatives,the mutual solubility of ILs and non-polar or weak-polar hydrocarbons are systematically studied based on the COSMO-RS *** reliability of COSMO-RS for these systems is first evaluated by comparing experimental and predicted hydrocarbon-in-IL activity coefficient at infinite dilution and binary/ternary liquid-liquid equilibria of related ***,the mutual solubility of the four hydrocarbons and13,650 ILs(composed by 210 cations and 65 anions)are *** effect of different IL structural characteristics including alkyl chain length,cation family/symmetry/functional group,and anion on the IL-hydrocarbon mutual solubility behaviors are further analyzed by the analyses of interaction energy and screen charge *** mutual solubility databases and the structural effects identified thereon could provide useful guidance for IL selection in related applications.

关键词： C6-hydrocarbons Ionic liquids Mutual solubility COSMO-RS Structural effect analysis

Electrochemical filtration for drinking water purification:A review on membrane materials,mechanisms and roles

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Journal of Environmental Sciences 2024年第7期141卷 102-128页

作者： Yuying qi Donghao Li Shixuan Zhang Fengxiang Li tao Hua College of Environmental Science and Engineering Nankai UniversityTianjin 300350China Key Laboratory of Pollution Process and Environmental Criteria Ministry of EducationTianjin 300350China Tianjin Engineering Center of Environmental Diagnosis and Contamination Remediation Tianjin 300350China

Electrochemical filtration can not only enrich low concentrations of pollutants but also produce reactive oxygen species to interact with toxic pollutants with the assistance of a power supply,making it an effective strategy for drinking water *** addition,the application of electrochemical filtration facilitates the reduction of pretreatment procedures and the use of chemicals,which has outstanding potential for maximizing process simplicity and reducing operating costs,enabling the production of safe drinking water in smaller *** recent years,the research on electrochemical filtration has gradually increased,but there has been a lack of attention on its application in the removal of low concentrations of pollutants from low conductivity *** this review,membrane substrates and electrocatalysts used to improve the performance of electrochemical membranes are briefly ***,the application prospects of emerging single-atom catalysts in electrochemical filtration are also ***,several electrochemical advanced oxidation processes coupled with membrane filtration are described,and the related working mechanisms and their advantages and shortcomings used in drinking water purification are ***,the roles of electrochemical filtration in drinking water purification are presented,and the main problems and future perspectives of electrochemical filtration in the removal of low concentration pollutants are discussed.

关键词： Electrochemical filtration Drinking water Conductive membrane Low concentration Electrocatalyst

Hybrid pedestrian positioning system using wearable inertial sensors and ultrasonic ranging

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Defence Technology（防务技术） 2024年第3期33卷 327-338页

作者： Lin qi Yu Liu Chuanshun Gao tao Feng Yue Yu School of Communication and Information Engineering Chongqing University of Posts and TelecommunicationsChongqing 400065China Department of Land Surveying and Geo-Informatics The Hong Kong Polytechnic UniversityHong Kong 999077China

Pedestrian positioning system(PPS)using wearable inertial sensors has wide applications towards various emerging fields such as smart healthcare,emergency rescue,soldier positioning,*** performance of traditional PPS is limited by the cumulative error of inertial sensors,complex motion modes of pedestrians,and the low robustness of the multi-sensor collaboration *** paper presents a hybrid pedestrian positioning system using the combination of wearable inertial sensors and ultrasonic ranging(H-PPS).A robust two nodes integration structure is developed to adaptively combine the motion data acquired from the single waist-mounted and foot-mounted node,and enhanced by a novel ellipsoid constraint *** addition,a deep-learning-based walking speed estimator is proposed by considering all the motion features provided by different nodes,which effectively reduces the cumulative error originating from inertial ***,a comprehensive data and model dual-driven model is presented to effectively combine the motion data provided by different sensor nodes and walking speed estimator,and multi-level constraints are extracted to further improve the performance of the overall *** results indicate that the proposed H-PPS significantly improves the performance of the single PPS and outperforms existing algorithms in accuracy index under complex indoor scenarios.

关键词： Pedestrian positioning system Wearable inertial sensors Ultrasonic ranging Deep-learning Data and model dual-driven

Cobalt(Ⅲ)hydride HAT mediated enantioselective intramolecular hydroamination access to chiral pyrrolidines

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Science China Chemistry 2024年第6期67卷 2002-2008页

作者： qi Meng tao qin Huanran Miao Ge Zhang qian Zhang Jilin Province Key Laboratory of Organic Functional Molecular Design&Synthesis Department of ChemistryNortheast Normal UniversityChangchun130024China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai200032China

Enantioenriched pyrrolidines and derivatives are ubiquitous substructures in compounds of importance to medicinal and biological ***,we report an efficient cobalt-catalyzed intramolecular asymmetric hydroamination reaction that produces chiral pyrrolidines with good to excellent yield and *** with previously reported radicalinvolved methodologies for enantioenriched pyrrolidines,these conditions feature two elegant versatilities,enabling(1)the use of cobalt-catalyzed hydrogen atom transfer(HAT)to generate organocobalt intermediates that bring radical reaction to organometallic chemistry,and(2)enantioselective intramolecular C-N bond forging through an S_(N)2-like displacement involving dynamic kinetic resolution(DKR).This approach provides a new alternative and efficient methodology for enantioselective radical-involved C-N bond construction that can be used in the synthesis of both chiral pyrrolidines and homologous nitrogen heterocycles.

关键词： asymmetric catalysis radical hydroamination cobalt catalysis hydrogen atom transfer

Dammarane-type triterpenoids from Gynostemma longipes and their protective activities on hypoxia-induced injury in PC12 cells

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Chinese Journal of Natural Medicines 2024年第5期22卷 466-480页

作者： LIANG Haizhen CHEN Xiaojuan LI qi ZHANG Mengmeng LU Pengxin ZHANG Jie song Juan ZHANG tao GUO Baolin MA Baiping Department of Pharmaceutical Sciences Beijing Institute of Radiation MedicineBeijing 100850China Institute of Medicinal Plant Development Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100193China AnKang Chia Tai Pharmaceutical Co. Ltd.Shaanxi 725000China

Sixteen new dammarane-type triterpenoid saponins(1-16)featuring diverse structural variations in the side chain at C-17,along with twenty-one known analogues(17-37),have been isolated from the rhizomes of Gynostemma longipes ***,a plant renowned for its medicinal and edible *** structural elucidation of these compounds was accomplished through comprehensive analyses of 1D and 2D NMR and HRMS spectroscopic data,supplemented by comparison with previously reported *** assays on the isolates for their protective effects against hypoxia-induced damage in pheochromocytoma cells(PC12 cells)revealed that nine saponins exhibited significant anti-hypoxic *** investigation into the anti-hypoxia mechanisms of the representative saponins demonstrated that compounds 22 and 36 markedly reduced the levels of hypoxia-induced ***,these compounds were found to decrease the release of lactate dehydrogenase(LDH)and malondialdehyde(MDA),while increasing the activity of superoxide dismutase(SOD),thereby indicating that the saponins could mitigate hypoxia-induced injuries by ameliorating apoptosis and oxidative *** findings offer substantial evidence for the future utilization and development of ***,identifying dammarane-type triterpenoid saponins as its active anti-hypoxic constituents.

关键词： Gynostemma longipes Dammarane-type saponins Anti-hypoxia effect Apoptosis