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Ultrathin two-dimensional electrocatalysts: Structure-property relationships, mechanistic insights, and applications in water electrolysis
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作者 Lina Wang Muhan Na +5 位作者 Ruofei Du Xiujin Wang Boyang Yu Lan Yang Hui Chen Xiaoxin Zou 《Chinese Journal of Catalysis》 2025年第10期4-19,共16页
The pursuit of sustainable hydrogen production has positioned water electrolysis as a cornerstone technology for global carbon neutrality.However,sluggish kinetics,catalyst scarcity,and system integration challenges h... The pursuit of sustainable hydrogen production has positioned water electrolysis as a cornerstone technology for global carbon neutrality.However,sluggish kinetics,catalyst scarcity,and system integration challenges hinder its widespread deployment.Ultrathin two-dimensional(2D)materials,with their atomically exposed surfaces,tunable electronic structures,and defect-engineering capabilities,present unique opportunities for next-generation electrocatalysts.This review provides an integrated overview of ultrathin 2D electrocatalysts,discussing their structural diversity,synthetic routes,structure-activity relationships,and mechanistic understanding in water electrolysis processes.Special focus is placed on the translation of 2D materials from laboratory research to practical device implementation,emphasizing challenges such as scalable fabrication,interfacial engineering,and operational durability in realistic electrolyzer environments.The role of advanced characterization techniques in capturing dynamic structural changes and active site evolution is discussed.Finally,we outline future research directions,emphasizing the synergy of machine learning-driven materials discovery,advanced operando characterization,and scalable system integration to accelerate the industrial translation of 2D electrocatalysts for green hydrogen production. 展开更多
关键词 two-dimensional material Water splitting reaction ELECTROCATALYSIS Catalytic mechanism ELECTROLYZER
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Multi-party semi-quantum private comparison protocol of size relation based on two-dimensional Bell states
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作者 Bing Wang Li-Hua Gong San-Qiu Liu 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第11期184-192,共9页
Currently,all quantum private comparison protocols based on two-dimensional quantum states can only compare equality,via using high-dimensional quantum states that it is possible to compare the size relation in existi... Currently,all quantum private comparison protocols based on two-dimensional quantum states can only compare equality,via using high-dimensional quantum states that it is possible to compare the size relation in existing work.In addition,it is difficult to manipulate high-dimensional quantum states under the existing conditions of quantum information processing,leading to low practicality and engineering feasibility of protocols for comparing size relation.Considering this situation,we propose an innovative protocol.The proposed protocol can make size comparison by exploiting more manageable two-dimensional Bell states,which significantly enhances its feasibility with current quantum technologies.Simultaneously,the proposed protocol enables multiple participants to compare their privacies with the semi-quantum model.The communication process of the protocol is simulated on the IBM Quantum Experience platform to verify its effectiveness.Security analysis shows that the proposed protocol can withstand common attacks while preserving the privacies of all participants.Thus,the devised protocol may provide an important reference for implementation of quantum private size comparison protocols. 展开更多
关键词 two-dimensional Bell state size relation multi-party semi-quantum private comparison
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Labor Relations数据集构造决策树的新方法
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作者 黄俊南 《保山学院学报》 2025年第2期60-70,共11页
采用新型多变量决策树算法对Labor Relations数据集构建决策树,成功获取完整决策表达式。算法在执行原始数据时表现准确无误,能有效处理多达16个条件属性的数据集。同时,证明算法在独立决策条件依赖关系的判定有效,也发现约简法则存在... 采用新型多变量决策树算法对Labor Relations数据集构建决策树,成功获取完整决策表达式。算法在执行原始数据时表现准确无误,能有效处理多达16个条件属性的数据集。同时,证明算法在独立决策条件依赖关系的判定有效,也发现约简法则存在改进潜力。该算法构建决策逻辑过程易于理解且复杂度低,能很好地实现劳资关系样本数据的快速鉴别。 展开更多
关键词 人工智能 劳务关系 多变量决策树 集合运算 逻辑运算
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Wearable Biodevices Based on Two-Dimensional Materials:From Flexible Sensors to Smart Integrated Systems 被引量:1
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作者 Yingzhi Sun Weiyi He +3 位作者 Can Jiang Jing Li Jianli Liu Mingjie Liu 《Nano-Micro Letters》 2025年第5期207-255,共49页
The proliferation of wearable biodevices has boosted the development of soft,innovative,and multifunctional materials for human health monitoring.The integration of wearable sensors with intelligent systems is an over... The proliferation of wearable biodevices has boosted the development of soft,innovative,and multifunctional materials for human health monitoring.The integration of wearable sensors with intelligent systems is an overwhelming tendency,providing powerful tools for remote health monitoring and personal health management.Among many candidates,two-dimensional(2D)materials stand out due to several exotic mechanical,electrical,optical,and chemical properties that can be efficiently integrated into atomic-thin films.While previous reviews on 2D materials for biodevices primarily focus on conventional configurations and materials like graphene,the rapid development of new 2D materials with exotic properties has opened up novel applications,particularly in smart interaction and integrated functionalities.This review aims to consolidate recent progress,highlight the unique advantages of 2D materials,and guide future research by discussing existing challenges and opportunities in applying 2D materials for smart wearable biodevices.We begin with an in-depth analysis of the advantages,sensing mechanisms,and potential applications of 2D materials in wearable biodevice fabrication.Following this,we systematically discuss state-of-the-art biodevices based on 2D materials for monitoring various physiological signals within the human body.Special attention is given to showcasing the integration of multi-functionality in 2D smart devices,mainly including self-power supply,integrated diagnosis/treatment,and human–machine interaction.Finally,the review concludes with a concise summary of existing challenges and prospective solutions concerning the utilization of2D materials for advanced biodevices. 展开更多
关键词 two-dimensional material Wearable biodevice Flexible sensor Smart integrated system Healthcare
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Inhibitory effect of the interlayer of two-dimensional vermiculite on the polysulfide shuttle in lithium-sulfur batteries
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作者 CHEN Xiaoli LUO Zhihong +3 位作者 XIONG Yuzhu WANG Aihua CHEN Xue SHAO Jiaojing 《无机化学学报》 北大核心 2025年第8期1661-1671,共11页
A functional interlayer based on two-dimensional(2D)porous modified vermiculite nanosheets(PVS)was obtained by acid-etching vermiculite nanosheets.The as-obtained 2D porous nanosheets exhibited a high specific surface... A functional interlayer based on two-dimensional(2D)porous modified vermiculite nanosheets(PVS)was obtained by acid-etching vermiculite nanosheets.The as-obtained 2D porous nanosheets exhibited a high specific surface area of 427 m^(2)·g^(-1)and rich surface active sites,which help restrain polysulfides(LiPSs)through good physi-cal and chemical adsorption,while simultaneously accelerating the nucleation and dissolution kinetics of Li_(2)S,effec-tively suppressing the shuttle effect.The assembled lithium-sulfur batteries(LSBs)employing the PVS-based inter-layer delivered a high initial discharge capacity of 1386 mAh·g^(-1)at 0.1C(167.5 mAh·g^(-1)),long-term cycling stabil-ity,and good rate property. 展开更多
关键词 vermiculite nanosheets two-dimensional materials INTERLAYER shuttle effect lithium-sulfur batteries
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New Features and New Challenges of U.S.-Europe Relations Under Trump 2.0 被引量:1
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作者 Zhao Huaipu 《Contemporary World》 2025年第3期47-52,共6页
During Donald Trump’s first term,the“Trump Shock”brought world politics into an era of uncertainties and pulled the transatlantic alliance down to its lowest point in history.The Trump 2.0 tsunami brewed by the 202... During Donald Trump’s first term,the“Trump Shock”brought world politics into an era of uncertainties and pulled the transatlantic alliance down to its lowest point in history.The Trump 2.0 tsunami brewed by the 2024 presidential election of the United States has plunged the U.S.-Europe relations into more gloomy waters,ushering in a more complex and turbulent period of adjustment. 展开更多
关键词 new features turbulent period Trump U S Europe relations presidential election new challenges UNCERTAINTIES transatlantic alliance
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Finite-Time Expected Present Value of Operating Costs until Ruin in a Two-Dimensional Risk Model with Periodic Observation
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作者 TENG Ye XIE Jiayi ZHANG Zhimin 《应用概率统计》 北大核心 2025年第5期748-765,共18页
This paper investigates ruin,capital injection,and dividends for a two-dimensional risk model.The model posits that surplus levels of insurance companies are governed by a perturbed composite Poisson risk model.This m... This paper investigates ruin,capital injection,and dividends for a two-dimensional risk model.The model posits that surplus levels of insurance companies are governed by a perturbed composite Poisson risk model.This model introduces a dependence between the two surplus levels,present in both the associated perturbations and the claims resulting from common shocks.Critical levels of capital injection and dividends are established for each of the two risks.The surplus levels are observed discretely at fixed intervals,guiding decisions on capital injection,dividends,and ruin at these junctures.This study employs a two-dimensional Fourier cosine series expansion method to approximate the finite time expected discounted operating cost until ruin.The ensuing approximation error is also quantified.The validity and accuracy of the method are corroborated through numerical examples.Furthermore,the research delves into the optimal capital allocation problem. 展开更多
关键词 two-dimensional risk model Fourier cosine expansion capital injection DIVIDEND
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MXenes-based separators with nanoconfined two-dimensional channels for high-performance lithium-sulfur battery
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作者 Yi-Hui Zhao Shuai Li +6 位作者 Yu-Lu Huo Zhen Li Lan-Lan Hou Yong-Qiang Wen Xiao-Xian Zhao Jian-Jun Song Jing-Chong Liu 《Rare Metals》 2025年第5期2921-2944,共24页
Lithium-sulfur(Li-S)batteries with high energy density and capacity have garnered significant research attention among various energy storage devices.However,the shuttle effect of polysulfides(LiPSs)remains a major ch... Lithium-sulfur(Li-S)batteries with high energy density and capacity have garnered significant research attention among various energy storage devices.However,the shuttle effect of polysulfides(LiPSs)remains a major challenge for their practical application.The design of battery separators has become a key aspect in addressing the challenge.MXenes,a promising two-dimensional(2D)material,offer exceptional conductivity,large surface area,high mechanical strength,and active sites for surface reactions.When assembled into layered films,MXenes form highly tunable two-dimensional channels ranging from a few angstroms to over 1 nm.These nanoconfined channels are instrumental in facilitating lithium-ion transport while effectively impeding the shuttle effect of LiPSs,which are essential for improving the specific capacity and cyclic stability of Li-S batteries.Substantial progress has been made in developing MXenes-based separators for Li-S batteries,yet there remains a research gap in summarizing advancements from the perspective of interlayer engineering.This entails maintaining the 2D nanochannels of layered MXenes-based separators while modulating the physicochemical environment within the MXenes interlayers through targeted modifications.This review highlights advancements in in situ modification of MXenes and their integration with 0D,1D,and 2D materials to construct laminated nanocomposite separators for Li-S batteries.The future development directions of MXenes-based materials in Li-S energy storage devices are also outlined,to drive further advancements in MXenes for Li-S battery separators. 展开更多
关键词 Lithium-sulfur battery MXenes SEPARATOR two-dimensional materials two-dimensional nanochannels
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Congratulatory Message by H.E.Mr.Chatchai Viriyavejakul,Ambassador of the Kingdom of Thailand to the People’s Republic of China On the Occasion of the 50th Anniversary of the Establishment of Thailand-China Diplomatic Relations
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《China Report ASEAN》 2025年第6期23-23,共1页
I am delighted to join my Thai and Chinese friends in celebrating the 50th anniversary of the establishment of diplomatic relations between our two great nations.It is the“Golden Jubilee”of Thailand-China friendship... I am delighted to join my Thai and Chinese friends in celebrating the 50th anniversary of the establishment of diplomatic relations between our two great nations.It is the“Golden Jubilee”of Thailand-China friendship.Half a century ago when Thailand’s then Prime Minister M.R.Kukrit Pramoj and China’s Premier Zhou Enlai signed a Joint Communique on the Establishment of Diplomatic Relations on July 1,1975,the foundation for a profound and mutually beneficial partnership was laid,fostering enduring friendship,cooperation,and understanding between our two nations.This bond has stood the test of time amidst the ever-changing international landscape and been further enhanced by both countries’commitment to advancing the Comprehensive Strategic Cooperative Partnership and building a Thailand-China community with a shared future for enhanced stability,prosperity,and sustainability through a forwardlooking and people-centered vision. 展开更多
关键词 shared future Thailand China relations diplomatic relations comprehensive strategic cooperative partnership establishment diplomatic relations golden jubilee
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A Review of Joint Extraction Techniques for Relational Triples Based on NYT and WebNLG Datasets
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作者 Chenglong Mi Huaibin Qin +1 位作者 Quan Qi Pengxiang Zuo 《Computers, Materials & Continua》 2025年第3期3773-3796,共24页
In recent years,with the rapid development of deep learning technology,relational triplet extraction techniques have also achieved groundbreaking progress.Traditional pipeline models have certain limitations due to er... In recent years,with the rapid development of deep learning technology,relational triplet extraction techniques have also achieved groundbreaking progress.Traditional pipeline models have certain limitations due to error propagation.To overcome the limitations of traditional pipeline models,recent research has focused on jointly modeling the two key subtasks-named entity recognition and relation extraction-within a unified framework.To support future research,this paper provides a comprehensive review of recently published studies in the field of relational triplet extraction.The review examines commonly used public datasets for relational triplet extraction techniques and systematically reviews current mainstream joint extraction methods,including joint decoding methods and parameter sharing methods,with joint decoding methods further divided into table filling,tagging,and sequence-to-sequence approaches.In addition,this paper also conducts small-scale replication experiments on models that have performed well in recent years for each method to verify the reproducibility of the code and to compare the performance of different models under uniform conditions.Each method has its own advantages in terms of model design,task handling,and application scenarios,but also faces challenges such as processing complex sentence structures,cross-sentence relation extraction,and adaptability in low-resource environments.Finally,this paper systematically summarizes each method and discusses the future development prospects of joint extraction of relational triples. 展开更多
关键词 relation triplet extraction joint extraction methods named entity recognition relation extraction
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REVITALIZING TIES FOR A SHARED FUTURE China and the Philippines need to work together to bring bilateral relations back to a track of healthy and stable development
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作者 Ye Jingtong Ma Yuchen 《China Report ASEAN》 2025年第6期56-59,共4页
The year 2025 marks the 50th anniversary of diplomatic relations between China and the Philippines.Over the past half century,despite ups and downs,China-Philippines relations have maintained a steady momentum of deve... The year 2025 marks the 50th anniversary of diplomatic relations between China and the Philippines.Over the past half century,despite ups and downs,China-Philippines relations have maintained a steady momentum of development with continuous progress in political,economic,and cultural exchanges.Since the second half of 2023,the Philippines’freguent provocations in the South China Sea have negatively impacted bilateral relations. 展开更多
关键词 shared future diplomatic relations bilateral relations China political exchanges Philippines South China Sea economic exchanges
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Two-Dimensional TiO_(2)Ultraviolet Filters for Sunscreens
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作者 Ling QiuHui-Ming Cheng Ruoning Yang +10 位作者 Jiefu Chen Xiang Li Yaxin Zhang Baofu Ding Yujiangsheng Xu Shaoqiang Luo Shaohua Ma Xingang Ren Gang Liu Ling Qiu Hui-Ming Cheng 《Nano-Micro Letters》 2025年第12期108-119,共12页
Titanium dioxide(TiO_(2))has been an important protective ingredient in mineral-based sunscreens since the 1990s.However,traditional TiO_(2)nanoparticle formulations have seen little improvement over the past decades ... Titanium dioxide(TiO_(2))has been an important protective ingredient in mineral-based sunscreens since the 1990s.However,traditional TiO_(2)nanoparticle formulations have seen little improvement over the past decades and continue to face persistent challenges related to light transmission,biosafety,and visual appearance.Here,we report the discovery of two-dimensional(2D)TiO_(2),characterized by a micro-sized lateral dimension(~1.6μm)and atomic-scale thickness,which fundamentally resolves these long-standing issues.The 2D structure enables exceptional light management,achieving 80%visible light transparency—rendering it nearly invisible on the skin—while maintaining UV-blocking performance comparable to unmodified rutile TiO_(2)nanoparticles.Its larger lateral size results in a two-orders-of-magnitude reduction in skin penetration(0.96 w/w%),significantly enhancing biosafety.Moreover,the unique layered architecture inherently suppresses the generation of reactive oxygen species(ROS)under sunlight exposure,reducing the ROS generation rate by 50-fold compared to traditional TiO_(2)nanoparticles.Through precise metal element modulation,we further developed the first customizable sunscreen material capable of tuning UV protection ranges and automatically matching diverse skin tones.The 2D TiO_(2)offers a potentially transformative approach to modern sunscreen formulation,combining superior UV protection,enhanced safety and a natural appearance. 展开更多
关键词 two-dimensional Titanium dioxide SUNSCREEN BIOSAFETY
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WEAPONIZING TRADE, UNDERMINING TRUST The Trump administration’s politicization of global economics threatens international stability and damages China-U.S. relations
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作者 Hamzah Rifaat Hussain 《China Report ASEAN》 2025年第5期64-64,共1页
If there were any doubts about the Trump administration’s inherent obsession with decoupling,polarization and jolting of global trade,they can be laid to rest.A series of statements and measures have been made by the... If there were any doubts about the Trump administration’s inherent obsession with decoupling,polarization and jolting of global trade,they can be laid to rest.A series of statements and measures have been made by the U.S.government on economic relations with China including administrative decision to hit Chinese goods with additional tariffs despite China. 展开更多
关键词 global trade economic relations trade decoupling international stability tariffs polarization TRUST china u s relations
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Stronger Ties and a Shared Future Indonesian Ambassador Djauhari Oratmangun reflects on 75 years of Indonesia-China relations and prospects for deeper collaboration
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作者 Huang Jiangqin 《China Report ASEAN》 2025年第4期22-23,共2页
The year 2025 marks the 75th anniversary of the establishment of diplomatic relations between China and Indonesia.Over the past 75 years,the bilateral relationship has made significant progress across various fields,l... The year 2025 marks the 75th anniversary of the establishment of diplomatic relations between China and Indonesia.Over the past 75 years,the bilateral relationship has made significant progress across various fields,laying a solid foundation for regional stability.China Report ASEAN interviewed Indonesian Ambassador to China Djauhari Oratmangun to reflect on the remarkable journey of Indonesia-China relations over the past 75 years. 展开更多
关键词 Indonesia China relations regional stability djauhari oratmangun diplomatic relations th anniversary bilateral relationship shared future
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An Evaluation and Similarity Analysis of Provincial Green Development Levels in China Using Grey Relational Analysis
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作者 Fan Bo Chen Qian 《Contemporary Social Sciences》 2025年第1期47-68,共22页
Green development is vital for bringing about high-quality development,which makes measuring and comparing provincial green development levels essential.This study calculates the comprehensive green development scores... Green development is vital for bringing about high-quality development,which makes measuring and comparing provincial green development levels essential.This study calculates the comprehensive green development scores using panel data from 30 Chinese provinces and autonomous regions(2013-2022)and a combined subjective-objective weighting method.It also innovatively establishes a grey relational degree matrix and a grey improvement sequence to analyze provincial similarities and identify benchmarks for improvement.The results indicate that ecological and environmental protection holds the highest weight among the primary indicators.Beijing,Shanghai,Tianjin,Zhejiang,and Jiangsu lead in green development,with Shanghai,Beijing,and Tianjin exhibiting distinct development trajectories,while Guizhou and Yunnan share a similar trend.Zhejiang and Shaanxi have prominent benchmarks for improvement,while some provinces dynamically adjust their targets.The results suggest that advanced regions should further refine their green development pathways to align with their specific contexts,while less-developed regions should adaptively learn from the appropriate benchmarks and periodically reassess their strategies.This study provides scientific guidance for regional green development planning,policymaking,and benchmarking,thus contributing to sustainable regional development.Furthermore,it lays a foundation for future research to expand into broader datasets,scales,influencing factors,and policy evaluations. 展开更多
关键词 green development grey relational degree grey relational degree matrix grey improvement sequence benchmark for improvement
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Analysis of Leakage Effects on Outlet Flow Characteristics of a Two-dimensional Piston Pump
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作者 Yu Huang Hanyu Xu +2 位作者 Wei Shao Chuan Ding Li Liu 《Chinese Journal of Mechanical Engineering》 2025年第3期545-557,共13页
Owing to their rolling friction,two-dimensional piston pumps are highly suitable as power components for electro-hydrostatic actuators(EHAs).These pumps are particularly advantageous for applications requiring high ef... Owing to their rolling friction,two-dimensional piston pumps are highly suitable as power components for electro-hydrostatic actuators(EHAs).These pumps are particularly advantageous for applications requiring high efficiency and reliability.However,the ambiguity surrounding the output flow characteristics of individual two-dimensional pumps poses a significant challenge in achieving precise closed-loop control of the EHA positions.To address this issue,this study established a comprehensive numerical model that included gap leakage to analyze the impact of leakage on the output flow characteristics of a two-dimensional piston pump.The validity of the numerical analysis was indirectly confirmed through meticulous measurements of the leakage and volumetric efficiency,ensuring robust results.The research findings indicated that,at lower pump speeds,leakage significantly affected the output flow rate,leading to potential inefficiencies in the system.Conversely,at higher rotational speeds,the impact of leakage was less pronounced,implying that the influence of leakage on the pump outlet flow must be carefully considered and managed for EHAs to perform position servo control.Additionally,the research demonstrates that two-dimensional motion does not have a unique or additional effect on pump leakage,thus simplifying the design considerations.Finally,the study concluded that maintaining an oil-filled leakage environment is beneficial because it helps reduce the impact of leakage and enhances the overall volumetric efficiency of the pump system. 展开更多
关键词 two-dimensional piston pump LEAKAGE Numerical simulation CLEARANCE
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Two-dimensional nanomaterials for environmental catalysis roadmap towards 2030
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作者 Jing Guo Jianzhong Ma +18 位作者 Junli Liu Guanjie Huang Xiaoting Zhou Francesco Parrino Riccardo Ceccato Leonardo Palmisano Boon-Junn Ng Lutfi Kurnianditia Putri Huaxing Li Rongjie Li Gang Liu Yang Wang Nikolay Kornienko Shan-Shan Zhu Zhenwei Zhang Xiaoming Liu Nur Atika Nikma Dahlan Siang-Piao Chai Jianmin Ma 《Chinese Chemical Letters》 2025年第9期223-235,共13页
Environmental catalysis has been considered one of the important research topics.Some technologies(e.g.,photocatalysis and electrocatalysis)have been intensively developed with the advance of synthetic technologies of... Environmental catalysis has been considered one of the important research topics.Some technologies(e.g.,photocatalysis and electrocatalysis)have been intensively developed with the advance of synthetic technologies of catalytical materials.In 2019,we discussed the development trend of this field,and wrote a roadmap on this topic in Chinese Chemical Letters(30(2019)2065-2088).Nowadays,we discuss it again from a new viewpoint along this road.In this paper,several subtopics are discussed,e.g.,photocatalysis based on titanium dioxide,violet phosphorus,graphitic carbon and covalent organic frameworks,electrocatalysts based on carbon,metal-and covalent-organic framework.Finally,we hope that this roadmap can enrich the development of two-dimensional materials in environmental catalysis with novel understanding,and give useful inspiration to explore new catalysts for practical applications. 展开更多
关键词 Environmental catalysis two-dimensional materials ELECTROCATALYSIS PHOTOCATALYSIS NANOMATERIALS
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Synthesis of two-dimensional diamond by phase transition from graphene at atmospheric pressure
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作者 Songyang Li Zhiguang Zhu +2 位作者 Youzhi Zhang Chengke Chen Xiaojun Hu 《Chinese Physics B》 2025年第5期596-607,共12页
It is a key challenge to prepare two-dimensional diamond(2D-diamond).Herein,we develop a method for synthesizing 2D-diamond by depositing monodisperse tantalum(Ta)atoms onto graphene substrates using a hot-filament ch... It is a key challenge to prepare two-dimensional diamond(2D-diamond).Herein,we develop a method for synthesizing 2D-diamond by depositing monodisperse tantalum(Ta)atoms onto graphene substrates using a hot-filament chemical vapor deposition setup,followed by annealing treatment under different temperatures at ambient pressure.The results indicate that when the annealing temperature increases from 700℃ to 1000℃,the size of the 2D-diamond found in the samples gradually increases from close to 20 nm to around 30 nm.Meanwhile,the size and number of amorphous carbon spheres and Ta-containing compounds between the graphene layers gradually increase.As the annealing temperature continues to rise to 1100℃,a significant aggregation of Ta-containing compounds is observed in the samples,with no diamond structure detected.This further confirms that monodisperse Ta atoms play a key role in graphene phase transition into 2D-diamond.This study provides a novel method for the ambient-pressure phase transition of graphene into 2D-diamond. 展开更多
关键词 GRAPHENE two-dimensional diamond vacuum annealing phase transition
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Exciton insulators in two-dimensional systems
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作者 Huaiyuan Yang Xi Dai Xin-Zheng Li 《Chinese Physics B》 2025年第9期496-505,共10页
Electron-hole interactions play a crucial role in determining the optoelectronic properties of materials,and in lowdimensional systems this is especially true due to the decrease of screening.In this review,we focus o... Electron-hole interactions play a crucial role in determining the optoelectronic properties of materials,and in lowdimensional systems this is especially true due to the decrease of screening.In this review,we focus on one unique quantum phase induced by the electron-hole interaction in two-dimensional systems,known as“exciton insulators”(EIs).Although this phase of matter has been studied for more than half a century,suitable platforms for its stable realization remain scarce.We provide an overview of the strategies to realize EIs in accessible materials and structures,along with a discussion on some unique properties of EIs stemming from the band structures of these materials.Additionally,signatures in experiments to distinguish EIs are discussed. 展开更多
关键词 excitonic insulator two-dimensional materials
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China-EU Cooperation Could Not Have Been Better Timed--On the Occasion of the 50th Anniversary of China-EU Diplomatic Relations
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作者 《Contemporary World》 2025年第4期22-27,共6页
This year marks the 50th anniversary of the establishment of diplomatic relations between China and the EU.Over half a century,China and the EU have steadily enhanced political mutual trust,deepened mutually beneficia... This year marks the 50th anniversary of the establishment of diplomatic relations between China and the EU.Over half a century,China and the EU have steadily enhanced political mutual trust,deepened mutually beneficial cooperation,and firmly upheld multilateralism,bringing tangible benefits to both peoples and making a significant contribution to global peace and development. 展开更多
关键词 EU Mutually Beneficial Cooperation Political Mutual Trust China Diplomatic relations enhanced political mutual trustdeepened establishment diplomatic relations MULTILATERALISM
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