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Chinese Journal of Chemistry 2024年第13期42卷 1481-1486页

作者： Shuaichen Zhang jing Zhang Xiang Ling Yifan Zhao Yue ma Peng Sun State Key Laboratory for Quality Ensurance and Sustainable Use of Dao-di Herbs Artemisinin Research Center and Institute of Chinese Materia MedicaChina Academy of Chinese Medical SciencesBeijing 100700China Department of Pharmaceutics School of PharmacyChina Pharmaceutical UniversityState Key Laboratory of Natural MedicinesNanjingJiangsu 210009China

Organic difluoroboron complexes are a kind of potential platforms for a wide range of applications owing to their excellent photophysical ***,we have explored a simple and direct synthesis methodology for a library of N,O-bidentate difluoroboron complexes from quinoxalin-2(1H)-ones and ketones in one *** photophysical properties of the generated complexes were evaluated and the application potential of these compounds on subcellular imaging was also explored.

关键词： N,O-Bidentate difluoroboron Chromophores Quinoxalin-2(1H)-ones Ketones/Green chemistry Synthetic method C-CcouplingI Boron

Feasibility study of the photonuclear reaction cross section of medical radioisotopes using a laser Compton scattering gamma source

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Nuclear Science and Techniques 2024年第9期35卷 168-177页

作者： Yu-Ning Gu Wei-Juan Zhao Xi-Guang Cao Yu-Xuan Yang Ting-kai ma Zheng-Li Liao Fei-Long Xu Yu-Gang ma School of Physics and Microeletronics Zhengzhou UniversityZhengzhou 450001China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China School of Nuclear Science and Technology University of South ChinaHengyang 421001China Key Laboratory of Nuclear Physics and Ion-beam Application(MOE) Institute of Modern PhysicsFudan UniversityShanghai 200433China Shanghai Research Center for Theoretical Nuclear Physics NSFC and Fudan UniversityShanghai 200438China

In recent years,the gap between the supply and demand of medical radioisotopes has increased,necessitating new methods for producing medical *** reactions based on gamma sources have unique advantages in terms of producing high specific activity and innovative medical ***,the lack of experimental data on reaction cross sections for photonuclear reactions of medical radioisotopes of interest has severely limited the development and production of photonuclear transmutation medical *** this study,the entire process of the generation,decay,and measurement of medical radioisotopes was simulated using online gamma activation and offline gamma measurements combined with a shielding gamma-ray *** on a quasi-monochromatic gamma beam from the Shanghai Laser Electron Gamma Source(SLEGS),the feasibility of this measurement of production cross section for surveyed medi-cal radioisotopes was simulated,and specific solutions for measuring medical radioisotopes with ultra-low production cross sections were *** feasibility of this method for high-precision measurements of the reaction cross section of medical radioisotopes was demonstrated.

关键词： Medical radioisotope Photonuclear reaction GEANT4 Shanghai Laser Electron Gamma Source(SLEGS) Low-background gamma-ray spectrometer

Nitrogen–sulfur co-doped porous carbon derived from asphalt as efficient catalyst for oxygen reduction

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Rare Metals 2024年第1期43卷 380-388页

作者： jing-Sheng ma Ming-Zai Wu Ling Chen Li-Xing Zhang Ying Xiong Key Laboratory of Structure and Functional Regulation of Hybrid materials Ministry of EducationInstitute of EnergyHefei Comprehensive National Science CenterAnhui UniversityHefei 230601China

As an environment-friendly and low-cost petrochemical by-product, asphalt has great potential in the preparation of metal-free oxygen reduction electrocatalysts with excellent performance and outstanding stability. In this paper, we converted asphalt into porous carbon nanosheets by a simple activation method, using potassium citrate as the swelling agent.

关键词： stability porous catalyst

Enhancing personalized exercise recommendation with student and exercise portraits

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Journal of Electronic Science and Technology 2024年第2期22卷 91-109页

作者： Wei-Wei Gao Hui-Fang ma Yan Zhao jing Wang Quan-Hong Tian College of Computer Science and Engineering Northwest Normal UniversityLanzhou730070China Computer Center of Gansu Province Lanzhou730070China

The exercise recommendation system is emerging as a promising application in online learning scenarios,providing personalized recommendations to assist students with explicit learning *** solutions generally follow a collaborative filtering paradigm,while the implicit connections between students(exercises)have been largely *** this study,we aim to propose an exercise recommendation paradigm that can reveal the latent connections between student-student(exercise-exercise).Specifically,a new framework was proposed,namely personalized exercise recommendation with student and exercise portraits(PERP).It consists of three sequential and interdependent modules:Collaborative student exercise graph(CSEG)construction,joint random walk,and recommendation list ***,CSEG is created as a unified heterogeneous graph with students’response behaviors and student(exercise)***,a joint random walk to take full advantage of the spectral properties of nearly uncoupled markov chains is performed on CSEG,which allows for full exploration of both similar exercises that students have finished and connections between students(exercises)with similar ***,we propose to optimize the recommendation list to obtain different exercise *** analyses of two public datasets,the results demonstrated that PERP can satisfy novelty,accuracy,and diversity.

关键词： Educational data mining Exercise recommend Joint random walk Nearly uncoupled markov chains Optimization Personalized learning

Production induced fracture closure of deep shale gas well under thermo-hydro-mechanical conditions

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Petroleum Science 2024年第3期21卷 1796-1813页

作者： Shi-Ming Wei Yang Xia Yan Jin Xu-Yang Guo jing-Yu Zi kai-Xuan Qiu Si-Yuan Chen College of Science China University of Petroleum(Beijing)Beijing102249China CNOOC Research Institute Ltd Beijing100028China The University of Hong Kong Hong Kong999077China

Deep shale gas reservoirs have geological characteristics of high temperature,high pressure,high stress,and inferior ability to pass through *** multi-stage fractured horizontal well is the key to exploiting the deep shale gas ***,during the production process,the effectiveness of the hydraulic fracture network decreases with the closure of fractures,which accelerates the decline of shale gas *** this paper,we addressed the problems of unclear fracture closure mechanisms and low accuracy of shale gas production prediction during deep shale gas *** we established the fluid—solid—heat coupled model coupling the deformation and fluid flow among the fracture surface,proppant and the shale *** the fluid—solid—heat coupled model was applied to the fracture network,it was well solved by our numerical method named discontinuous discrete fracture *** with the conventional discrete fracture method,the discontinuous discrete fracture method can describe the three-dimensional morphology of the fracture while considering the effect of the change of fracture surface permeation coefficient on the coupled fracture—matrix flow and describing the displacement discontinuity across the *** simulations revealed that the degree of fracture closure increases as the production time proceeds,and the degree of closure of the secondary fractures is higher than that of the primary *** creep and proppant embedment both increase the degree of fracture *** reduction in fracture surface permeability due to proppant embedment reduces the rate of fluid transfer between matrix and fracture,which has often been overlooked in the ***,it significantly impacts shale gas production,with calculations showing a 24.7%cumulative three-year yield *** study is helpful to understand the mechanism of hydraulic fracture ***,it provides the theoretical guidance for maintaining the long

关键词： Shalegas Fracture closure Fluid-solid-heat coupling Discontinuous discrete fracture

Adsorption behavior of CO2/H2S mixtures in calcite slit nanopores for CO2 storage:An insight from molecular perspective

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Petroleum Science 2024年第4期21卷 2444-2456页

作者： Cheng Qian Zhen-Hua Rui Yue-Liang Liu kai Du Chen Liu Yang Zhao Xiao-Min ma State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum College of Petroleum Engineering China University of Petroleum College of Carbon Neutrality Future Technology China University of Petroleum College of Petroleum China University of Petroleum-Beijing at Karamay College of Mining Engineering Taiyuan University of Technology

It is acknowledged that injecting CO2into oil reservoirs and saline aquifers for storage is a practical and affordable method for *** CO2produced from industrial exhaust contains impurity gases such as H2S that might impact CO2sequestration due to competitive *** study makes a commendable effort to explore the adsorption behavior of CO2/H2S mixtures in calcite slit *** Canonical Monte Carlo（GCMC） simulation is employed to reveal the adsorption of CO2,H2S as well as their binary mixtures in calcite *** show that the increase in pressure and temperature can promote and inhibit the adsorption capacity of CO2and H2S in calcite nanopores,***2exhibits stronger adsorption on calcite surface than *** energy plays the dominating role in the adsorption *** energy accounts for 97.11% of the CO2-calcite interaction energy and 56.33% of the H2S-calcite interaction energy at 10 MPa and 323.15 *** presence of H2S inhibits the CO2adsorption in calcite nanopores due to competitive adsorption,and a higher mole fraction of H2S leads to less *** quantity of CO2adsorbed is lessened by approximately 33% when the mole fraction of H2S reaches ***2molecules preferentially occupy the regions near the po re wall and H2S molecules tend to reside at the center of nanopore even when the molar ratio of CO2is low,indicating that CO2has an adsorption priority on the calcite surface over *** addition,moisture can weaken the adsorption of both CO2and H2S,while CO2is more *** interestingly,we find that pure CO2is more suitable to be sequestrated in the shallower formations,i.e.,500-1500 m,whereas CO2with H2S impurity should be settled in the deeper reservoirs.

关键词： Adsorption behavior CO 2 /H 2 S binary mixtures Molecular perspective Calcite slit nanopores CO 2 sequestration

Efficient and rapid capture of uranium(Ⅵ) in wastewater via multiamine modified β-cyclodextrin porous polymer

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Chinese Journal of Chemical Engineering 2024年第4期68卷 144-155页

作者： Xing Zhong Yubin Tan Siyuan Wu Caixia Hu kai Guo Yongchuan Wu Neng Yu Mingyang ma Ying Dai School of Chemistry and materials Science East China University of TechnologyNanchang 330013China

It is quite important to ensure the safety and sustainable development of nuclear energy for the treatment of radioactive wastewater. To treat radioactive wastewater efficiently and rapidly, two multi-amine β-cyclodextrin polymers(diethylenetriamine β-cyclodextrin polymer(DETA-TFCDP) and triethylenetetramine β-cyclodextrin polymer(TETA-TFCDP)) were prepared and applied to capture uranium. Results exhibited that DETA-TFCDP and TETA-TFCDP displayed the advantages of high adsorption amounts(612.2and 628.2 mg·g-1, respectively) and rapid adsorption rates, which can reach(88 ± 1)% of their equilibrium adsorption amounts in 10 min. Moreover, the adsorbent processes of DETA-TFCDP and TETATFCDP on uranium(Ⅵ) followed the Langmuir model and pseudo-second-order model, stating they were mainly chemisorption and self-endothermic. Besides, TETA-TFCDP also showed excellent selectivity in the presence of seven competing cations and could be effectively reused five times via Na2CO3as the desorption reagent. Meanwhile, X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy illustrated that the enriched multi-amine groups and oxygen-containing functional groups on the surface of TETA-TFCDP were the main active sites for capturing uranium(Ⅵ). Hence, multi-amine β-cyclodextrin polymers are a highly efficient, rapid, and promising adsorbent for capturing uranium(Ⅵ)from radioactive wastewater.

关键词： Adsorption Waste water Pollution Uranium(VI) b-Cyclodextrin

MXene supported PtCo bimetallic catalyst for hydrogen evolution in acidic conditions

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Frontiers in Energy 2024年第3期18卷 369-377页

作者： Guangxun CHEN Jian-hua ZHANG kai-Ling ZHOU Yang YANG Haoxiang ma Yuhong JIN jingbin LIU Hao WANG Faculty of materials and manufacturing Beijing University of TechnologyBeijing 100124China Institute of Deep-Sea Science and Engineering Chinese Academy of SciencesSanya 572000China

Using the electrochemical technology to split water molecules to produce hydrogen is the key to obtain green hydrogen for solving the energy crisis. The large-scale application of hydrogen evolution reaction (HER) in water dissociation requires a highly active catalyst. In this paper, the highly dispersed PtCo bimetallic nanoparticles loading on MXene (PtCo/MXene) were prepared by using a step-to-step reduction strategy. The mentioned PtCo/MXene catalyst exhibits a high current density of −100 ma/cm2 in an acidic medium with just a 152 mV overpotential. In addition, the PtCo/MXene catalyst also displays a superior stability. Computational analysis and experimental testing demonstrate that the electronic interaction between Pt and Co can effectively modify the electronic structure of the active site, thereby enhancing the inherent catalytic performance of the material. More importantly, MXene two-dimensional nanosheets can expose more active sites because of their large specific surface area. Furthermore, MXene substrate with excellent electrical conductivity and harmonious interfaces between PtCo and MXene enhance charge transfer efficiency and lower the reaction activation energy.

关键词： MXene PtCo bimetallic hydrogen evolution reaction(HER)

A layered multifunctional framework based on polyacrylonitrile and MOF derivatives for stable lithium metal anode

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Journal of Energy Chemistry 2024年第6期93卷 282-288,I0007页

作者： Fanfan Liu Peng Zuo jing Li Pengcheng Shi Yu Shao Linwei Chen Yihong Tan Tao ma Engineering Research Center of High-frequency Soft magnetic materials and Ceramic Powder materials of Anhui Province School of Chemistry and Material EngineeringChaohu UniversityHefei 238024AnhuiChina Frontiers Science Center for Transformative Molecules School of Chemistry and Chemical EngineeringShanghai Jiao Tong UniversityShanghai 200240China School of Pharmacy Anhui University of Chinese MedicineHefei 230012AnhuiChina School of materials and Energy Guangdong University of TechnologyGuangzhou 510006GuangdongChina Jiujiang DeFu Technology Co. Ltd.Jiujiang 332000JiangxiChina

Composite Li metal anodes based on three-dimensional(3D) porous frameworks have been considered as an effective material for achieving stable Li metal batteries with high energy ***,uneven Li deposition behavior still occurs at the top of 3D frameworks owing to the local accumulation of Li *** promote uniform Li deposition without top dendrite growth,herein,a layered multifunctional framework based on oxidation-treated polyacrylonitrile(OPAN) and metal-organic framework(MOF) derivatives was proposed for rationally regulating the distribution of Li ions flux,nucleation sites,and electrical *** from these merits,the OPAN/carbon nano fiber-MOF(CMOF) composite framework demonstrated a reversible Li plating/stripping behavior for 500 cycles with a stable Coulombic efficiency of around 99.0% at the current density of 2 ma/cm~***,such a Li composite anode exhibited a superior cycle lifespan of over 1300 h under a low polarized voltage of 18 mV in symmetrical *** the Li composite anode was paired with LiFePO_(4)(LFP) cathode,the obtained full cell exhibited a stable cycling over 500 ***,the COMSOL Multiphysics simulation was conducted to reveal the effects on homogeneous Li ions distribution derived from the above-mentioned OPAN/CMOF framework and electrical insulation/conduction *** electrochemical and simulated results shed light on the difficulties of designing stable and safe Li metal anode via optimizing the 3D frameworks.

关键词： Lithium metal anode Layered multifunctional framework Ions flux redistribution Electrical insulation/conduction structure Uniform Li deposition

Effect of two-step solid solution on microstructure andδphase precipitation of Inconel 718 alloy

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International Journal of Minerals,Metallurgy and materials 2024年第10期31卷 2199-2207页

作者： Enyu Liu Qingshuang ma Xintong Li Aoxue Gao jing Bai Liming Yu Qiuzhi Gao Huijun Li School of materials Science and Engineering Northeastern UniversityShenyang 110819China School of Resources and materials Northeastern University at QinhuangdaoQinhuangdao 066004China School of materials Science&Engineering Tianjin UniversityTianjin 300354China School of Mechanical Materials and Mechatronic EngineeringUniversity of WollongongWollongongNSW 2522Australia

Inconel 718 is the most popular nickel-based superalloy and is extensively used in aerospace,automotive,and energy indus-tries owing to its extraordinary thermomechanical *** effects of different two-step solid solution treatments on microstructure andδphase precipitation of Inconel 718 alloy were studied,and the transformation mechanism fromγ″metastable phase toδphase was *** precipitates were statistically analyzed by X-ray *** results show that theδphase content firstly increased,and then decreased with the temperature of the second-step solid *** changes in microstructure andδphase were studied by scanning electron microscopy and transmission electron *** intragranularδphase formed in Inconel 718 alloy at the second-[100]_(δ)[011]γ step solid solution temperature of 925℃,and its orientation relationship withγmatrix was determined as//and(010)_(δ)//(111)γ.Furthermore,the Vickers hardness of different heat treatment samples was measured,and the sample treated by second-step solid solution at 1010℃ reached the maximum hardness of HV 446.84.

关键词： Inconel 718 alloy two-step solid solution treatment δphase γ″-δtransformation