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Electrochemical Multicomponent Cascade Radical Process Enabling Synthesis of lodomethyl Spiropyrrolidinyl-Oxindoles

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Chinese Journal of Chemistry 2024年第15期42卷 1691-1698页

作者： Jingrui He Haibo mei Jorge Escorihuela Jianlin Han Jiangsu Co-lnnovation Center of Efficient Processing and Utilization of Forest Resources College of Chemical EngineeringNanjingForestryUniversityNanjingJiangsu210037ChinaDepartamento de Quimica OrganicaUniversitat de ValenciaAvda.Vicente Andres Estelles s/nBurjassot 46100ValenciaSpain

A novel electrochemical multicomponent cascade reaction of indole-tethered alkenes with CF_(3)SO_(2)Na and n-BuaNI has been developed,which enables the rapid assembly of spiropyrrolidinyl-oxindoles in good *** experimental results and DFT calculations suggest that this reaction proceeds through the oxidation of CF_(3)SO_(2)Na,radical coupling with alkene,spirocyclization,oxidation of sulfinate,iodide substitution,and water *** strategy features mild reaction conditions,easy-to-handle reactants,and good chemical *** finding not only enriches the research contents of indole-tethered alkenes but also provides a green strategy for the construction of spiropyrrolidinyl-oxindoles compared with the existing methodologies.

关键词： Spiropyrrolidinyl-oxindoles Electrosynthesis Indole-tethered alkenes CF_(3)SO_(2)Na DFT calculation Multicomponent reaction Radical reactions Cross-Coupling Greenchemistry

Counterion-Mediated Hydrogen Bonding Making Strong Polyelectrolytes pH-Responsive:Current Understanding and Perspectives

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Chinese Journal of Polymer Science 2024年第9期42卷 1270-1277,I0005页

作者： Yue Huang Guang-Tao mei Zan Hua Guang-Ming Liu Hefei National Research Center for Physical Sciences at the Microscale Department of Chemical PhysicsKey Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education InstitutesUniversity of Science and Technology of ChinaHefei230026China The Key Laboratory of Functional Molecular Solids Ministry of Educationand Department of Materials ChemistrySchool of Chemistry and Materials ScienceAnhui Normal UniversityWuhu214002China

The counterion-mediated hydrogen bonding(CMHB)is related to the hydrogen bonding between bound counterions and polyelectrolyte chains in polyelectrolyte systems,where the counterions can both electrostatically bind to the charged groups of polyelectrolyte chains and act as hydrogen bond donors or acceptors to form hydrogen bonds with the hydrogen bond sites associated with polyelectrolyte chains simultaneously.A large number of literatures illustrate that strong polyelectrolytes(SPs)are insensitive to pH,which severely limmits the applications of SPs as smart ***,our studies have demonstrated that the CMHB makes SPs *** perspective discusses the mechanism of pH responsiveness of SPs and the pH-tunable properties of SPs,based on the pH-controlled CMHB *** future research directions on the pH responsiveness of SPs are also discussed *** is anticipated that the study of the pH responsiveness of SPs not only will provide a new understanding of the fundamental properties of SPs,but also will greatly expand the applications of SPs in the field of smart materials.

关键词： Counterion binding Hydrogen bond Polyelectrolyte brush Polyelectrolyte complexation

Chemical Activation of S/Li2S in Li-S Batteries by a Bidirectional Organic Redox Mediator

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CHEMICAL RESEARCH IN CHINESE UNIVERSITIES 2024年第5期40卷 927-934页

作者： Li, Chengqiu Zhou, Chaoyong mei, Shilin Yao, Changjiang Beijing Inst Technol Sch Mechatron Engn State Key Lab Explos Sci & Safety Protect Beijing 100081 Peoples R China Xian Safty Energy Technol Co Ltd Xian 710299 Peoples R China

The energy density and lifespan of prototype Li-S batteries under high sulfur loading and lean electrolyte have been mainly restricted by the incomplete interconversion between insulating S8 and Li2S. The introduction of an electrocatalyst has been preserved as an effective way to breakthrough the bottleneck of the interconversion rate. Herein, we demonstrate a novel bidirectional redox mediator, insoluble dithiobisphthalimide (DTPI), as the electrocatalyst for both S8 reduction and Li2S oxidation. Due to the dual-functional role of both electron/Li+ donor and acceptor, DTPI can efficiently accelerate the redox reactions during charge/discharge and significantly alleviate the incomplete conversion of sulfur species. Consequently, the Li-S batteries with DTPI deliver superior specific capacity and cycling stability in comparison with those without DTPI. Especially, the redox mediator is scalable for synthesis and the DTPI-based 5 Ah pouch cell delivers a specific discharge capacity of around 870 mAhg(-1) at 0.1 C (1 C=1675 mA/g) without capacity fading over 80 cycles. The bidirectional catalysis mechanism has been studied through theoretical calculation and ex-situ characterization of the cathode materials. This work approves the effectiveness of bidirectional organic redox mediator in the construction of practical Li-S batteries.

关键词： Lithium-sulfur battery (LSB) Dithiobisphthalimide (DTPI) Organic redox mediator Interconversion LITHIUM FRAMEWORK

Recent progress of in-situ characterization of LiNi_(1−x−y)Co_(x)Mn_(y)O_(2) cathodes for lithium metal batteries: A mini review

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Nano Research 2024年第3期17卷 1384-1401页

作者： Huanzhu Lv Xiaoqi Zhu Jun mei Yuanhua Xia Bin Wang Institute of Fundamental and Frontier Science University of Electronic Science and Technology of ChinaChengdu 611731China Chengdu Development Center of Science and Technology China Academy of Engineering PhysicsChengdu 610200China Key Laboratory of Neutron Physics and Institute of Nuclear Physics and Chemistry China Academy of Engineering Physics(CAEP)Mianyang 621999China

In the context of the gradual popularity of electric vehicles(EVs),the development of lithium battery systems with high energy density and power density is regarded as the foremost way to improve the range of ***_(1-x-y)Co_(x)Mn_(y)O_(2)(NCM)cathodes have been the focus of researchers due to their high energy density,excellent power performance,and low-temperature ***,the elaboration of the decay mechanism of NCM cathode based on lithium metal batteries(LMBs)is still being restricted to the primary *** the past decades,the development and application of advanced in-situ characterization tools have facilitated researchers'understanding of the internal operation mechanism of batteries during charging and *** this minireview,the latest progress of in-situ observation of the NCM cathode by X-ray diffraction(XRD),fourier transform infrared(FT-IR)spectroscopy,Raman spectroscopy,atomic force microscopy(AFM),transmission electron microscope(TEM),optical microscope,and other characterization tools is *** mechanisms of structural degradation,cathode-electrolyte interfaces(CEIs)composition,and dynamic changes of NCM,electrolyte breakdown,and gas production are ***,based on the existing research progress,the opportunities and challenges for future in-situ characterization technology in the study of the mechanism of LMBs are discussed in ***,the purpose of this minireview is to summarize recent work that focuses on the outstanding application of in-situ characterization techniques in the mechanistic study of LMBs,and pointing the way to the future development of high energy density and power density LMBs systems.

关键词： lithium metal batteries(LMBs) In-situ characterization LiNi_(1-x-y)Co_(x)Mn_(y)O_(2)(NCM)

Dynamics of a Reaction-diffusion-ODE System in a Heterogeneous Media

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 275-301页

作者： Cong-hui ZHANG Hai-feng ZHANG mei-rong ZHANG School of Science Beijing University of Civil Engineering and ArchitectureBeijing 102616China Institute of Applied System Analysis Jiangsu UniversityZhenjiang 212013China Department of Mathematical Sciences Tsinghua UniversityBeijing 100084China

The existence and stability of stationary solutions for a reaction-diffusion-ODE system are investigated in this *** first show that there exist both continuous and discontinuous stationary *** a good understanding of the stability of discontinuous stationary solutions is gained under an appropriate *** addition,we demonstrate the influences of the diffusion coefficient on stationary *** results we obtained are based on the super-/sub-solution method and the generalized mountain pass ***,some numerical simulations are given to illustrate the theoretical results.

关键词： reaction-diffusion-ODE system discontinuous stationary solutions stability asymptotic behavior monotone solutions

Relationship between the Stratospheric Arctic Vortex and Surface Air Temperature in the Midlatitudes of the Northern Hemisphere

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Journal of Meteorological Research 2024年第1期38卷 39-52页

作者： Xue RAN Dingzhu HU Yang ZHANG mei-Chen LIU Key Laboratory of Meteorological Disaster Ministry of Education(KLME)/Joint International Research Laboratory of Climate and Environmental Change(ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)Nanjing University of Information Science&TechnologyNanjing 210044 School of Atmospheric Sciences Nanjing UniversityNanjing 210023

It is known that different relationships exist between the strength and displacement of the stratospheric polar vortex(SPV),and the surface air temperature(SAT)patterns in Eurasia and North America,but the mechanisms behind these relationships remain unclear,especially on an interannual *** on empirical orthogonal function(EOF)analysis using NCEP reanalysis data over 1958–2018,this study attempts to ascertain the relationship between the SPV intensity and displacement over the Arctic and the SATs in the midlatitudes of the Northern *** results indicate that a strengthened SPV corresponds to an SAT increase in Eurasia and a decrease in eastern North America and *** the SPV is shifted towards Eurasia,however,a corresponding SAT increase occurs in both North America and Eurasia,with a larger increase in North America than in ***,a strengthened SPV tends to correspond to a positive North Atlantic Oscillation-like circulation in the troposphere with negative geopotential height(GH)anomalies in Greenland and eastern North American continent and positive GH anomalies to the north of 45°N in Eurasia,which corresponds to lower SATs in North America than in ***,when the SPV shifted towards Eurasia,it was accompanied by a positive Pacific/North American-like pattern with a deepened Aleutian low,which corresponds to the increasing SATs in North *** tropospheric circulation changes are related to the response of tropospheric planetary wave activity to the SPV.A strengthened SPV corresponds to the weakening of tropospheric planetary wave-1 waves,which is accompanied by a negative GH in North America but a positive GH in *** the SPV shifted towards Eurasia,the tropospheric planetary wave-1(-2)waves strengthened(weakened),and the combined effects of the planetary wave-1 and wave-2 waves would cause positive GH anomalies in both Eurasia and North America.

关键词： stratospheric polar vortex surface air temperature teleconnection patterns planetary waves

Machine learning-driven optimization of plasma-catalytic dry reforming of methane

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Journal of Energy Chemistry 2024年第9期96卷 153-163页

作者： Yuxiang Cai Danhua mei Yanzhen Chen Annemie Bogaerts Xin Tu Department of Electrical Engineering and Electronics University of LiverpoolLiverpool L693GJUK Research Group PLASMANT Department of ChemistryUniversity of AntwerpUniversiteitsplein 1BE-2610 Wilrijk-AntwerpBelgium College of Electrical Engineering and Control Science Nanjing Tech UniversityNanjing 211816JiangsuChina

This study investigates the dry reformation of methane(DRM)over Ni/Al_(2)O_(3)catalysts in a dielectric barrier discharge(DBD)non-thermal plasma reactor.A novel hybrid machine learning(ML)model is developed to optimize the plasma-catalytic DRM reaction with limited experimental *** address the non-linear and complex nature of the plasma-catalytic DRM process,the hybrid ML model integrates three well-established algorithms:regression trees,support vector regression,and artificial neural networks.A genetic algorithm(GA)is then used to optimize the hyperparameters of each algorithm within the hybrid ML *** ML model achieved excellent agreement with the experimental data,demonstrating its efficacy in accurately predicting and optimizing the DRM *** model was subsequently used to investigate the impact of various operating parameters on the plasma-catalytic DRM *** found that the optimal discharge power(20 W),CO_(2)/CH_(4)molar ratio(1.5),and Ni loading(7.8 wt%)resulted in the maximum energy yield at a total flow rate of∼51 mL/***,we investigated the relative significance of each operating parameter on the performance of the plasma-catalytic DRM *** results show that the total flow rate had the greatest influence on the conversion,with a significance exceeding 35%for each output,while the Ni loading had the least impact on the overall reaction *** hybrid model demonstrates a remarkable ability to extract valuable insights from limited datasets,enabling the development and optimization of more efficient and selective plasma-catalytic chemical processes.

关键词： Plasma catalysis Machine learning Process optimization Dry reforming of methane Syngas production

Preparation and performance improvement of a dual-component microcapsule self-healing system for silicone rubber insulating material

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High Voltage 2024年第2期9卷 453-465页

作者： Mingzhe Li Bin Cao Fanghui Yin Hongwei mei Liming Wang Engineering Laboratory of Power Equipment Reliability in Complicated Coastal Environments Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhenChina

A key factor limiting the development of silicone rubber insulating materials is their short service life in harsh operating *** establishment of a self-healing system is desired to improve the long-term operational performance of silicone rubber and effectively extend its service *** this study,poly(urea-formaldehyde)microcapsules containing polydimethylsiloxane healing agents are prepared and a dual-component microcapsule self-healing system for silicone rubber material is established and *** addition,the key factors affecting the self-healing performance(such as microcapsule size,rupture rate,and microcapsule doping amount)are *** is found that when SYLGARDTM 184 is used as the healing agent and matrix,with a 4:6(A:B)doping ratio of dual-component microcapsules and 20 phr doping amount,the self-healing efficiency is approximately 51%.Furthermore,increasing the microcapsule rupture rate and the interface strength between the healing agent and the matrix can effectively improve the self-healing *** relationships between key factors and self-healing performance are theoretically *** on the relationships,the microcapsule self-healing system can be appropriately *** results of this paper can provide a reference for the development of long-life silicone rubber insulating materials.

关键词： service rubber performance

Control of aluminum distribution in ZSM-5 zeolite for enhancement of its catalytic performance for propane aromatization

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Frontiers of Chemical Science and Engineering 2024年第8期18卷 15-24页

作者： Zhao Ma Dezhi Shi Sen Wang mei Dong Weibin Fan State Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001China University of Chinese Academy of Sciences Beijing 100049China

Regulation of aluminum distribution in zeolite framework is an effective method for improving its catalytic performance for propane ***,we found that recrystallization and post-realuminization of ZSM-5 cannot only create hollow structures to enhance the diffusion ability,but also adjust the content and position of paired aluminum species in its *** characterizations results confirmed that increase of paired aluminum content and inducement of more aluminum atoms sited in the intersection cavity are beneficial to the formation of aromatic products in propane *** a result,the hollow-structured ZSM-5 zeolite with more paired aluminum(H-200-hollow)showed higher propane conversion and aromatics selectivity than other samples at the same *** catalytic performance of H-200-hollow can be further improved by ion-exchanging with a small amount of Ga(III)*** propane conversion and aromatics selectivity of Ga-200-hollow reached as high as 95%and 70%,respectively,at 540°C and 1 atm.

关键词： propane aromatization zeolite aluminum distribution recrystallization and post-realuminization