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Science China Mathematics 2025年第1期68卷 1-18页

作者： Masataka Iwai chen Jiang Haidong liu Department of Mathematics Graduate School of ScienceOsaka University Shanghai Center for Mathematical Sciences & School of Mathematical Sciences Fudan University Department of mathematics Sun Yat-sen University

In this paper,we study Miyaoka-type inequalities on Chern classes of terminal projective 3-folds with nef anti-canonical *** X be a terminal projective 3-fold such that-KXis *** show that if c1（X） · c2（X）≠0,then c1（X） · c2（X） ≥ 1/252;if further X is not rationally connected,then c1（X） · c2（X） ≥ 4/5 and this inequality is *** order to prove this,we give a partial classification of such varieties along with many *** also study the nonvanishing of c1（X）dim X-2· c2（X） for terminal weak Fano varieties and prove a Miyaoka-Kawamata-type inequality.

关键词： terminal threefolds Miyaoka-type inequality boundedness

Post-tunable salt gel electrolytes toward flexible supercapacitor switches

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Journal of Energy Chemistry 2025年第1期100卷 114-124页

作者： Hui Wang Shuang chen Xuming liu Qin Zhang Xin liu Polymeric and Soft Materials Laboratory School of Chemistry and Life Science and Advanced Institute of Materials Science Changchun University of Technology Polymeric and Soft Materials Laboratory School of Chemical Engineering and Advanced Institute of Materials Science Changchun University of Technology

Convertible hydrogel supercapacitors have emerged as promising energy storage devices in switches,diodes, and transistors. However, inherent weaknesses in ionic conductivity, mechanical properties,and water retention of hydrogel electrolytes seriously hinder their development. Inspired by the hardness conversion of sea cucumber skin, a conductivity and mechanics dual-tunable salt gel electrolyte is successfully designed. The salt gel presents a reversible switching of conductors-insulators and a mechanical regulation between softness and hardness via the dissolution-crystallization transition of sodium acetate trihydrate（SAT）. Meanwhile, the salt gels spontaneously grow a layer of “armor” through saturated phase-change salt crystals effectively reducing water evaporation of hydrogel ***, this phase-change soft-rigid conversion strategy will expand the capabilities of gel-based flexible supercapacitors(area capacitance: 258.6 mF cm-2), and the capacitance retention rate could still reach 86.9% after 3000 cycles at high temperatures. Moreover, the salt gel supercapacitor is potentially used in over-heat alarm systems. It is anticipated that the strategy of conductivity and mechanics of dual-tunable salt gel would provide a new perspective on the development of energy storage devices,wearable electronics, and flexible robots.

关键词： Capacitance

Boosting cationic and anionic redox activity of Li-rich layered oxide cathodes via Li/Ni disordered regulation

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Journal of Energy Chemistry 2025年第1期100卷 533-543页

作者： Zewen liu Zhen Wu Hao Wang Xudong Zhang Yuanzhen chen Yongning liu Shengwu Guo Shenghua chen Yanli Nan Yan liu State Key Laboratory for Mechanical Behavior of Materials Xi'an Jiaotong University School of Materials Science and Engineering Xi'an University of Architecture and Technology Hefei Advanced Computing Center Operation Management Corp Ltd Network Information Center Xi'an Jiaotong University

Lithium-rich layered oxides （LLOs） are increasingly recognized as promising cathode materials for nextgeneration high-energy-density lithium-ion batteries （LIBs）.However,they suffer from voltage decay and low initial Coulombic efficiency （ICE） due to severe structural degradation caused by irreversible O ***,we introduce a three-in-one strategy of increasing Ni and Mn content,along with Li/Ni disordering and TM–O covalency regulation to boost cationic and anionic redox activity simultaneously and thus enhance the electrochemical activity of *** target material,Li1.2Ni0.168Mn0.558Co0.074O2（L1）,exhibits an improved ICE of 87.2%and specific capacity of 293.2 mA h g-1and minimal voltage decay of less than 0.53 m V cycle-1over 300 cycles at 1C,compared to Li1.2Ni0.13Mn0.54Co0.13O2（Ls）(274.4 mA h g-1for initial capacity,73.8%for ICE and voltage decay of 0.84 mV/cycle over 300 cycles at 1C).Theoretical calculations reveal that the density of states （DOS） area near the Fermi energy level for L1 is larger than that of Ls,indicating higher anionic and cationic redox reactivity than ***,L1 exhibits increased O-vacancy formation energy due to higher Li/Ni disordering of 4.76%（quantified by X-ray diffraction Rietveld refinement） and enhanced TM–O covalency,making lattice O release more difficult and thus improving electrochemical *** increased Li/Ni disordering also leads to more Ni2+presence in the Li layer,which acts as a pillar during Li+de-embedding,improving structural *** research not only presents a viable approach to designing low-Co LLOs with enhanced capacity and ICE but also contributes significantly to the fundamental understanding of structural regulation in high-performance LIB cathodes.

关键词： Ice

Engineering atomic Rb-N configurations to tune radical pathways for highly selective photocatalytic H2O2 synthesis coupled with biomass valorization

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Journal of Energy Chemistry 2025年第1期100卷 215-225页

作者： Jiaye Li Shuang Pan Yihuang chen Qiong liu College of Chemistry and Materials Engineering Wenzhou University Guangdong Provincial Key Laboratory of Chemical Measurement and Emergency Test Technology (China) Institute of Analysis Guangdong Academy of Sciences (China National Analytical CenterGuangzhou)

Photocatalytic oxygen reduction for hydrogen peroxide （H2O2） synthesis presents a green and costeffective production ***,achieving highly selective H2O2synthesis remains challenging,necessitating precise control over free radical reaction pathways and minimizing undesirable oxidative ***,we report for the visible light-driven simultaneous co-photocatalytic reduction of O2to H2O2and oxidation of biomass using the atomic rubidium-nitride modified carbon nitride（CNRb）.The optimized CNRb catalyst demonstrates a record photoreduction rate of 8.01 mM h-1for H2O2generation and photooxidation rate of 3.75 mM h-1for furfuryl alcohol to furoic acid,achieving a remarkable solar-to-chemical conversion （SCC） efficiency of up to 2.27%.Experimental characterizations and DFT calculation disclosed that the introducing atomic Rb–N configurations allows for the high-selective generation of superoxide radicals while suppressing hydroxyl free radical *** is because the Rb–N serves as the new alternative site to perceive a stronger connection position for O2adsorption and reinforce the capability to extract protons,thereby triggering a high selective redox product *** study holds great potential in precisely regulating reactive radical processes at the atomic level,thereby paving the way for efficient synthesis of H2O2coupled with biomass valorization.

关键词： Free radical reactions

Si-C Foam Porous-Medium Combustion Power-Generation System for Low-Calorific-Value Biomass Syngas

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Journal of Thermal Science 2025年第1期34卷 206-222页

作者： YANG Jianwen chen Wei CAO Bingwei liu Xinhui LI Hang College of Mechanical and Aerospace Engineering Jilin University School of Mechanical and Vehicle Engineering Changchun University

Syngas produced from the gasification of organic feedstocks from biomass is one of the clean and sustainable sources of *** advantages of simple access and renewability of biomass energy can meet the energy needs of temporary power *** study presents a biomass power-generation system for vehicular *** biomass and a free-piston Stirling engine generator（FPSEG） as the primary material and prime mover,respectively,biomass energy is converted into electricity by combusting the syngas to heat the *** and key parameter design for biomass gasification and thermoelectric conversion systems within a power generation system were performed.A porous medium area was constructed using Si-C foam ceramics to obtain an energy-conversion experimental *** effects of bed height,porosity,porous-region diameter,and air-intake conditions on the power-generation performance were investigated,and optimisations were performed for the thermoelectric conversion *** rate of increase during FPSEG power generation first increased and then decreased with increasing bed height,peaking at a bed height of 40 *** increasing porous-region diameter accelerated FPSEG power generation,whereas porosity changes in the porous media did not significantly affect the rate of change during FPSEG power *** increasing air intake,the rate of increase during power generation first increased and then *** maximum change rate and the highest thermoelectric conversion efficiency of the power-generation system occurred at 9.5 m3/h and 6.5 m3/h（～45.1%）air intakes,*** the thermal inertia and combustion structure of the thermoelectric conversion system significantly increased the power-generation rate of the system,with 1.8 W/s being observed at a 9.7 m3/h air intake.

关键词： biomass combined heat and power (CHP) gasification porous media combustion power generation

Potential dependence in electrocatalysis: a theoretical perspective

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Science China Chemistry 2025年第1期68卷 21-25页

作者： Leyu liu Zhaoming Xia Zeyu Wang Yinjuan chen Hai Xiao Department of Chemistry Tsinghua University Fundamental Science Center of Rare Earths Ganjiang Innovation Academy Chinese Academy of Sciences Key Laboratory of Advanced Catalytic Materials and Technology Advanced Catalysis and Green Manufacturing Collaborative Innovation Center Changzhou University

Electrocatalysis is a key technology for the new energy era and sustainable development, serving as the interface for interconversion of electrical and chemical energies, which spans a wide spectrum of applications in sustainable energy and environmental engineering. Electrocatalytic reactions including electrochemical CO2reduction reaction （eCO2RR）, hydrogen evolution reaction （HER）, and oxygen evolution/reduction reactions （OER/ORR）, hold essential promise for renewable energy technologies as well as complement the biogeochemical carbon and oxygen cycles.

关键词：

Research progress of catalysts for direct coal liquefaction

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Journal of Energy Chemistry 2025年第1期100卷 481-497页

作者： Wei Song Penggao liu Xinyue chen Ting Wang Chunrong He Rui Hao Kaiyu liu State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources College of Chemistry Xinjiang University College of Chemistry and Chemical Engineering Henan Polytechnic University Hunan Provincial Key Laboratory of Chemical Power Sources College of Chemistry and Chemical Engineering Central South University

Coal direct liquefaction technology is a crucial contemporary coal chemical technology for efficient and clean use of coal resources. The development of direct coal liquefaction technology and the promotion of alternative energy sources are important measures to guarantee energy security and economic security. However, several challenges need to be addressed, including low conversion rate, inadequate oil yield, significant coking, demanding reaction conditions, and high energy consumption. Extensive research has been conducted on these issues, but further exploration is required in certain aspects such as pyrolysis of macromolecules during the liquefaction process, hydrogen activation, catalysts' performance and stability, solvent hydrogenation, as well as interactions between free radicals to understand their mechanisms better. This paper presents a comprehensive analysis of the design strategy for efficient catalysts in coal liquefaction, encompassing the mechanism of coal liquefaction, catalyst construction,and enhancement of catalytic conversion efficiency. It serves as a comprehensive guide for further research endeavors. Firstly, it systematically summarizes the conversion mechanism of direct coal liquefaction, provides detailed descriptions of various catalyst design strategies, and especially outlines the catalytic mechanism. Furthermore, it addresses the challenges and prospects associated with constructing efficient catalysts for direct coal liquefaction based on an understanding of their action mechanisms.

关键词： Direct coal liquefaction Catalysts Mechanism of action Solvent hydrogenation

A Generative Model-Based Network Framework for Ecological Data Reconstruction

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Computers, Materials & Continua 2025年第1期82卷 929-948页

作者： Shuqiao liu Zhao Zhang Hongyan Zhou Xuebo chen School of Electronic and Information Engineering University of Science and Technology LiaoningAnshan114051China School of Computer Science and Software Engineering University of Science and Technology LiaoningAnshan114051China

This study examines the effectiveness of artificial intelligence techniques in generating high-quality environmental data for species introductory site selection *** Strengths,Weaknesses,Opportunities,Threats(SWOT)analysis data with Variation Autoencoder(VAE)and Generative AdversarialNetwork(GAN)the network framework model(SAE-GAN),is proposed for environmental data *** model combines two popular generative models,GAN and VAE,to generate features conditional on categorical data embedding after SWOT *** model is capable of generating features that resemble real feature distributions and adding sample factors to more accurately track individual sample *** data is used to retain more semantic information to generate *** model was applied to species in Southern California,USA,citing SWOT analysis data to train the *** show that the model is capable of integrating data from more comprehensive analyses than traditional methods and generating high-quality reconstructed data from them,effectively solving the problem of insufficient data collection in development *** model is further validated by the Technique for Order Preference by Similarity to an Ideal Solution(TOPSIS)classification assessment commonly used in the environmental data *** study provides a reliable and rich source of training data for species introduction site selection systems and makes a significant contribution to ecological and sustainable development.

关键词： Convolutional Neural Network(CNN) VAE GAN TOPSIS data reconstruction

Ammonia pyrolysis oxidation excited by nanosecond pulsed discharge:Global/fluid models hybrid solution

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Journal of Energy Chemistry 2025年第1期100卷 385-396页

作者： Mingming Zhang Hanyu Wu Qi chen Jiaxin Yang Bonan liu School of Mechanical Electronic and Control Engineering Beijing Jiaotong University China University of Petroleum

The kinetic characteristics of plasma-assisted oxidative pyrolysis of ammonia are studied by using the global/fluid models hybrid solution ***,the stable products of plasma-assisted oxidative pyrolysis of ammonia are *** results show that the consumption of NH3/O2and the production of N2/H2change linearly with the increase of voltage,which indicates the decoupling of nonequilibrium molecular excitation and oxidative pyrolysis of ammonia at low ***,the detailed reaction kinetics mechanism of ammonia oxidative pyrolysis stimulated by a nanosecond pulse voltage at low pressure and room temperature is *** on the reaction path analysis,the simplified mechanism is *** detailed and simplified mechanism simulation results are compared with experimental data to verify the accuracy of the simplified ***,based on the simplified mechanism,the fluid model of ammonia oxidative pyrolysis stimulated by the nanosecond pulse plasma is established to study the pre-sheath/sheath behavior and the resultant consumption and formation of key *** results show that the generation,development,and propagation of the pre-sheath have a great influence on the formation and consumption of *** consumption of NH3by the cathode pre-sheath is greater than that by the anode pre-sheath,but the opposite is true for OH and O（1S）.However,within the sheath,almost all reactions do not ***,by changing the parameters of nanosecond pulse power supply voltage,it is found that the electron number density,electron current density,and applied peak voltages are not the direct reasons for the structural changes of the sheath and ***,the discharge interval has little effect on the sheath structure and gas mixture *** research results of this paper not only help to understand the kinetic promotion of non-equilibrium excitation in the process of oxidative pyrolysis but also help to explore th

关键词： Nanosecond pulsed discharge Ammonia Oxidative pyrolysis Fluid model Global model