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Multiverse/Hyperverse Models: (4 + 1)-Dimensional Landscape (Black Saturns, Bousso-Hawking Nucleation, Gogberashvili Multiverses, Schwarzschild-De Sitter Nurseries) and a (3 + 1)-Dimensional Model for Dark Energy
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作者 Igor Yu. Potemine Werner Krause 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第4期1866-1877,共12页
We consider the Hyperverse as a collection of multiverses in a (4 + 1)-dimensional spacetime with gravitational constant G. Multiverses in our model are bouquets of thin shells (with synchronized intrinsic times). If ... We consider the Hyperverse as a collection of multiverses in a (4 + 1)-dimensional spacetime with gravitational constant G. Multiverses in our model are bouquets of thin shells (with synchronized intrinsic times). If gis the gravitational constant of a shell Sand εits thickness, then G~εg. The physical universe is supposed to be one of those thin shells inside the local bouquet called Local Multiverse. Other remarkable objects of the Hyperverse are supposed to be black holes, black lenses, black rings and (generalized) Black Saturns. In addition, Schwarzschild-de Sitter multiversal nurseries can be hidden inside those Black Saturns, leading to their Bousso-Hawking nucleation. It also suggests that black holes in our physical universe might harbor embedded (2 + 1)-dimensional multiverses. This is compatible with outstanding ideas and results of Bekenstein, Hawking-Vaz and Corda about “black holes as atoms” and the condensation of matter on “apparent horizons”. It allows us to formulate conjecture 12.1 about the origin of the Local Multiverse. As an alternative model, we examine spacetime warping of our universe by external universes. It gives data for the accelerated expansion and the cosmological constant Λ, which are in agreement with observation, thus opening a possibility for verification of the multiverse model. 展开更多
关键词 5-Dimensional Gravity Black Hole Black Saturn Cosmological Constant Dark energy MULTIVERSE Spacetime Warping Thin Shell
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Crosstalk between degradation and bioenergetics: how autophagy and endolysosomal processes regulate energy production
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作者 Angelid Pabon Jagannatham Naidu Bhupana Ching-On Wong 《Neural Regeneration Research》 SCIE CAS 2025年第3期671-681,共11页
Cells undergo metabolic reprogramming to adapt to changes in nutrient availability, cellular activity, and transitions in cell states. The balance between glycolysis and mitochondrial respiration is crucial for energy... Cells undergo metabolic reprogramming to adapt to changes in nutrient availability, cellular activity, and transitions in cell states. The balance between glycolysis and mitochondrial respiration is crucial for energy production, and metabolic reprogramming stipulates a shift in such balance to optimize both bioenergetic efficiency and anabolic requirements. Failure in switching bioenergetic dependence can lead to maladaptation and pathogenesis. While cellular degradation is known to recycle precursor molecules for anabolism, its potential role in regulating energy production remains less explored. The bioenergetic switch between glycolysis and mitochondrial respiration involves transcription factors and organelle homeostasis, which are both regulated by the cellular degradation pathways. A growing body of studies has demonstrated that both stem cells and differentiated cells exhibit bioenergetic switch upon perturbations of autophagic activity or endolysosomal processes. Here, we highlighted the current understanding of the interplay between degradation processes, specifically autophagy and endolysosomes, transcription factors, endolysosomal signaling, and mitochondrial homeostasis in shaping cellular bioenergetics. This review aims to summarize the relationship between degradation processes and bioenergetics, providing a foundation for future research to unveil deeper mechanistic insights into bioenergetic regulation. 展开更多
关键词 AUTOPHAGY BIOENERGETICS endolysosome energy production GLYCOLYSIS metabolic reprogramming MITOCHONDRIA
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全球心血管疾病学术影响力评价(CAPE)体系的方法探索 被引量:2
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作者 尹潞 张雪燕 +7 位作者 曹也丁 李卫 姚焰 薄致远 魏良 蔡军 杨进刚 胡盛寿 《中国循环杂志》 CSCD 北大核心 2024年第1期3-16,共14页
目的:构建全球心血管疾病学术影响力评价(Cardiovascular Academic Performance Evaluation,CAPE)体系,并对全球医疗机构心血管疾病学术影响力进行排名。方法:由心血管疾病领域人员和图书情报人员提取医学主题词表(MeSH)、Embase同义词... 目的:构建全球心血管疾病学术影响力评价(Cardiovascular Academic Performance Evaluation,CAPE)体系,并对全球医疗机构心血管疾病学术影响力进行排名。方法:由心血管疾病领域人员和图书情报人员提取医学主题词表(MeSH)、Embase同义词表、国际疾病分类(ICD)中心血管疾病相关术语,建立心血管术语词表(即阜外词表),设定缺血性心脏病、高血压、血管疾病、心律失常、肺血管疾病、心力衰竭、先天性心脏病、心肌病和瓣膜性心脏病等9个亚学科,实现亚学科分类、心血管术语词、入口词的映射。检索Web of Science、PubMed、Scopus数据库2016年1月1日至2022年12月31日的心血管领域论文,并对元数据进行去重融合;应用阜外词表对论文中主题词、题目、关键词、摘要等4个位置的内容进行检索匹配,生成论文“位置-心血管术语词-频次”的信息表,计算每一篇论文心血管学科相关度积分及亚学科积分。对论文的机构名、学者名进行规范化清洗,基于心血管强相关(相关度积分≥4分)原创性论文开展全球心血管疾病领域学术影响力的评价。针对全国医疗机构(心血管)的科技评价,还采集了国家自然科学基金项目、授权发明专利、获奖成果、科研平台、注册试验[国家药品监督管理局药品审评中心(CDE)药物临床试验登记数据]等数据。结果:检索到全球2016~2022年心血管领域论文1545103篇,剔除摘要、书籍、传记、新闻、视频、音频、撤稿、更正声明后为1178019篇,使用阜外词表标引“心血管强相关”论文518058篇。还采集到11143项心血管相关国家自然科学基金项目、19382项心血管相关有效授权发明专利、103项心血管相关国家级获奖成果、24个心血管相关国家科研平台、2084项CDE心血管相关药物临床试验登记等数据。经组织心血管疾病及其亚学科专家团队针对各自亚学科论文进行核对和验证,改进学科分类规则,最终锁定11项指标构建了心血管疾病和9个亚学科领域的综合评价指标体系。2016~2022年,中国发表心血管疾病研究论文数量增幅为123.5%,共发表约7.68万篇,平均每天约30篇,仅次于美国(约11.41万篇),居世界第二位。但中国期刊引证报告(JCR)分区和中国科学院分区论文占比仅居世界第八位。在2020~2022年全球医疗机构心血管原创研究论文影响力综合评估中,仅2家中国医疗机构进入前20名。结论:CAPE项目基于2016~2022年多源数据基础,首次探索建立了心血管领域机构学术影响力综合评价指标体系。 展开更多
关键词 心血管疾病学术影响力评价(cape) 阜外词表 心血管疾病 科技评价
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基于CAPE-OPEN标准的简捷炼油过程建模及常减压蒸馏流程在线模拟
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作者 焦云强 陈玉石 王建平 《石油炼制与化工》 CAS CSCD 北大核心 2024年第8期164-177,共14页
简捷炼油过程模型广泛应用于运行监测、在线计算、实时优化等领域,但大多数模型只是将输入、输出变量进行关联,无法计算出各组分流量组成,难以集成在模拟软件中进行全流程模拟。本研究简化了炼油分离过程,开发了基于CAPE-OPEN标准的简... 简捷炼油过程模型广泛应用于运行监测、在线计算、实时优化等领域,但大多数模型只是将输入、输出变量进行关联,无法计算出各组分流量组成,难以集成在模拟软件中进行全流程模拟。本研究简化了炼油分离过程,开发了基于CAPE-OPEN标准的简捷炼油塔模型。首先,将炼油过程简化为连续的分离单元,根据实际产品数据校正模型参数,实现某一实际工况流程模拟;其次,将模型参数与实际工况操作变量数据相结合,采用径向基函数插值确定操作变量对模型参数的影响关系,实现多种工况流程模拟;最后,通过常减压蒸馏工业装置实例的3种工况进行验证。结果表明:各工况模拟结果与Aspen计算结果相比,初馏塔塔顶油馏出温度点偏差大多在2%以内,常减压蒸馏塔各侧线油的馏出温度点平均偏差在3%以内;与实际结果相比,平均误差都在5%以内,符合工程允许误差范围要求。所建模型的计算速度快,各塔均在0.2 s左右完成计算,适用于在线生产、调度等。 展开更多
关键词 简捷炼油模型 过程建模 cape-OPEN 在线模拟计算 常减压蒸馏装置
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Emerging importance of shale gas to both the energy & chemicals landscape 被引量:8
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作者 John N. Armor 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2013年第1期21-26,共6页
This perspectives article is intended highlight the growing importance and emergence of shale gas as an energy resource and as a source of chemicals. Over the next decades huge amounts of newly discovered deposits of ... This perspectives article is intended highlight the growing importance and emergence of shale gas as an energy resource and as a source of chemicals. Over the next decades huge amounts of newly discovered deposits of trapped gas are expected to be produced not only in the USA but elsewhere providing a wealth of methane and ethane not only used for energy production, but also for conversion to lower hydrocarbon chemicals. This manuscript seeks to focus on the potential of trapped natural gas around the world. The potential new volumes of trapped gas within shale or other mineral strata coming to the marketplace offer a tremendous opportunity if scientists can invent new, cost effective ways to convert this methane to higher value chemicals. Understanding how to selectively break a single C-H bond in methane while minimizing methane conversion to C02 is critical. 展开更多
关键词 applied catalysis: energy shale gas chemical and petrochemical processes methane activation
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Marine Renewable Energy Seascape 被引量:14
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作者 Alistair G.L.Borthwick 《Engineering》 SCIE EI 2016年第1期69-78,共10页
Energy production based on fossil fuel reserves is largely responsible for carbon emissions, and hence global warming. The planet needs concerted action to reduce fossil fuel usage and to implement carbon mitigation m... Energy production based on fossil fuel reserves is largely responsible for carbon emissions, and hence global warming. The planet needs concerted action to reduce fossil fuel usage and to implement carbon mitigation measures. Ocean energy has huge potential, but there are major interdisciplinary problems to be overcome regarding technology, cost reduction, investment, environmental impact, governance, and so forth. This article briefly reviews ocean energy production from offshore wind, tidal stream, ocean current, tidal range, wave, thermal, salinity gradients, and biomass sources. Future areas of research and development are outlined that could make exploitation of the marine renewable energy (MRE) seascape a viable proposition; these areas include energy storage, advanced materials, robotics, and informatics. The article concludes with a sustainability perspective on the MRE seascape encompassing ethics, leg- islation, the regulatory environment, governance and consenting, economic, social, and environmental constraints. A new generation of engineers is needed with the ingenuity and spirit of adventure to meet the global challenge posed by MRE. 展开更多
关键词 Marine renewable energy Offshore wind Tidal stream Ocean current Tidal range Wave energy Ocean thermal energyBioenergySustainability
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Noise-induced bistable switching dynamics through a potential energy landscape 被引量:2
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作者 Yuanhong Bi Zhuoqin Yang +1 位作者 Xiangying Meng Qishao Lu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2015年第2期216-222,共7页
Interlinked positive feedback loops,an important building block of biochemical systems,can induce bistable switching,leading to long-lasting state changes by brief stimuli.In this work,prevalent mutual activation betw... Interlinked positive feedback loops,an important building block of biochemical systems,can induce bistable switching,leading to long-lasting state changes by brief stimuli.In this work,prevalent mutual activation between two species as another positive feedback is added to a generic interlinked positive-feedback-loop model originating from many realistic biological circuits.A stochastic fluctuation of the positive feedback strength is introduced in a bistable interval of the feedback strength,and bistability appears for the moderate feedback strength at a certain noise level.Stability analysis based on the potential energy landscape is further utilized to explore the noise-induced switching behavior of two stable steady states. 展开更多
关键词 Stability Bifurcation Noise Bistable switching Potential energy landscape
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Equilibrium folding and unfolding dynamics to reveal detailed free energy landscape of src SH3 protein by magnetic tweezers 被引量:2
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作者 Huanhuan Su Hao Sun +3 位作者 Haiyan Hong Zilong Guo Ping Yu Hu Chen 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第7期595-599,共5页
Src SH3 protein domain is a typical two-state protein which has been confirmed by research of denaturant-induced unfolding dynamics.Force spectroscopy experiments by optical tweezers and atomic force microscopy have m... Src SH3 protein domain is a typical two-state protein which has been confirmed by research of denaturant-induced unfolding dynamics.Force spectroscopy experiments by optical tweezers and atomic force microscopy have measured the force-dependent unfolding rates with different kinds of pulling geometry.However,the equilibrium folding and unfolding dynamics at constant forces has not been reported.Here,using stable magnetic tweezers,we performed equilibrium folding and unfolding dynamic measurement and force-jump measurement of src SH3 domain with tethering points at its N-and C-termini.From the obtained force-dependent transition rates,a detailed two-state free energy landscape of src SH3 protein is constructed with quantitative information of folding free energy,transition state barrier height and position,which exemplifies the capability of magnetic tweezers to study protein folding and unfolding dynamics. 展开更多
关键词 protein folding and unfolding magnetic tweezers free energy landscape transition state
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Addressing the trade-climate change-energy nexus: China's explorations in a global governance landscape 被引量:2
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作者 Joachim MONKELBAAN 《Advances in Climate Change Research》 SCIE 2014年第4期206-218,共13页
We have arrived at a critical juncture when it comes to understanding the numerous ways in which trade interacts with climate change and energy(trade-climate-energy nexus).Trade remains crucial for the sustainable dev... We have arrived at a critical juncture when it comes to understanding the numerous ways in which trade interacts with climate change and energy(trade-climate-energy nexus).Trade remains crucial for the sustainable development of the world's greatest trading nation:China.After clarifying the linkages within the trade,climate change and energy nexus,this article delves into China's specific needs and interests related to trade,climate change and energy.Then it explores the ways in which trade can contribute to China's needs,to sustainable energy development and to the goals of the global climate agreement that is under negotiation.One main findings are China is a key participant in negotiations on trade liberalization of environmental technologies and services.These negotiations are in China's interests in terms of innovative industries,technological upgrading,employment and public health.China could stand up for the interests of other emerging and developing countries and serve as an example in terms of transitioning to a low-carbon economy.Beyond trade barriers issues of domestic(energy)regulation such as fossil-fuel subsidies as well as investment,competition-policy,tradefacilitation and transit issues related to clean energy need to be addressed.Building trust between relevant actors across sectors and national borders will be of the essence in order to foster long-term cooperation on technological innovation.As a way forward,different approaches towards the governance of trade and climate change will be highlighted.Besides discussing the specific aspects of Chinese participation in global trade and climate change governance,this paper aims at offering broader insights into the nexus between trade,energy and climate governance in China. 展开更多
关键词 Climate change TRADE GOVERNANCE Sustainable energy goods and services Investment Emissions trading
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Physical mechanism of mind changes and tradeoffs among speed,accuracy, and energy cost in brain decision making:Landscape, flux,and path perspectives 被引量:1
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作者 闫晗 张坤 汪劲 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第7期566-585,共20页
Cognitive behaviors are determined by underlying neural networks. Many brain functions, such as learning and memory, have been successfully described by attractor dynamics. For decision making in the brain, a quantita... Cognitive behaviors are determined by underlying neural networks. Many brain functions, such as learning and memory, have been successfully described by attractor dynamics. For decision making in the brain, a quantitative description of global attractor landscapes has not yet been completely given. Here, we developed a theoretical framework to quantify the landscape associated with the steady state probability distributions and associated steady state curl flux, measuring the degree of non-equilibrium through the degree of detailed balance breaking for decision making. We quantified the decision-making processes with optimal paths from the undecided attractor states to the decided attractor states, which are identified as basins of attractions, on the landscape. Both landscape and flux determine the kinetic paths and speed. The kinetics and global stability of decision making are explored by quantifying the landscape topography through the barrier heights and the mean first passage time. Our theoretical predictions are in agreement with experimental observations: more errors occur under time pressure. We quantitatively explored two mechanisms of the speed-accuracy tradeoff with speed emphasis and further uncovered the tradeoffs among speed, accuracy, and energy cost. Our results imply that there is an optimal balance among speed, accuracy, and the energy cost in decision making. We uncovered the possible mechanisms of changes of mind and how mind changes improve performance in decision processes. Our landscape approach can help facilitate an understanding of the underlying physical mechanisms of cognitive processes and identify the key factors in the corresponding neural networks. 展开更多
关键词 decision making non-equilibrium landscape and flux speed-accuracy tradeoff energy cost
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2024 Adult Compendium of Physical Activities:A third update of the energy costs of human activities 被引量:11
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作者 Stephen D.Herrmann Erik A.Willis +10 位作者 Barbara E.Ainsworth Tiago V.Barreira Mary Hastert Chelsea L.Kracht John M.Schuna Jr. Zhenghui Cai Minghui Quan Catrine Tudor-Locke Melicia C.Whitt-Glover David R. Jacobs Jr. 《Journal of Sport and Health Science》 SCIE CSCD 2024年第1期6-12,共7页
Background:The Compendium of Physical Activities was published in 1993 to improve the comparability of energy expenditure values assigned to self-reported physical activity(PA)across studies.The original version was u... Background:The Compendium of Physical Activities was published in 1993 to improve the comparability of energy expenditure values assigned to self-reported physical activity(PA)across studies.The original version was updated in 2000,and again in 2011,and has been widely used to support PA research,practice,and public health guidelines.Methods:This 2024 update was tailored for adults 19-59 years of age by removing data from those≥60 years.Using a systematic review and supplementary searches,we identified new activities and their associated measured metabolic equivalent(MET)values(using indirect calorimetry)published since 2011.We replaced estimated METs with measured values when possible.Results:We screened 32,173 abstracts and 1507 full-text papers and extracted 2356 PA energy expenditure values from 701 papers.We added303 new PAs and adjusted 176 existing MET values and descriptions to reflect the addition of new data and removal of METs for older adults.We added a Major Heading(Video Games).The 2024 Adult Compendium includes 1114 PAs(912 with measured and 202 with estimated values)across 22 Major Headings.Conclusion:This comprehensive update and refinement led to the creation of The 2024 Adult Compendium,which has utility across research,public health,education,and healthcare domains,as well as in the development of consumer health technologies.The new website with the complete lists of PAs and supporting resources is available at https://pacompendium.com. 展开更多
关键词 ADULTS energy expenditure EXERCISE MET Physical Activities
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基于CAPE-OPEN标准的乙苯脱氢反应器模块开发与全流程模拟
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作者 陈旭强 江洪波 +2 位作者 杨彩娟 陈玉石 欧阳福生 《石油炼制与化工》 CAS CSCD 北大核心 2024年第9期150-157,共8页
基于某乙苯负压绝热脱氢制苯乙烯装置转化率低于设计值的现状,建立了包括小分子水蒸气转化反应在内的乙苯绝热脱氢制苯乙烯反应动力学模型和反应器模型,基于工业数据,估计了模型动力学参数,模型具有较高的精度;采用C++语言和COM技术开... 基于某乙苯负压绝热脱氢制苯乙烯装置转化率低于设计值的现状,建立了包括小分子水蒸气转化反应在内的乙苯绝热脱氢制苯乙烯反应动力学模型和反应器模型,基于工业数据,估计了模型动力学参数,模型具有较高的精度;采用C++语言和COM技术开发了符合CAPE-OPEN标准的乙苯脱氢制苯乙烯反应器单元模块;在Aspen Plus平台构建了内嵌反应器模块的乙苯脱氢制苯乙烯全流程模型,反应器与精馏塔的模拟结果与实际相吻合;进一步考察了工艺参数对装置运行中期反应的影响,提出了适宜的工艺参数,为乙苯脱氢制苯乙烯的工艺设计、生产优化提供有益的支持。 展开更多
关键词 乙苯脱氢 苯乙烯 cape-OPEN标准 参数估计 流程模拟
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Older Adult Compendium of Physical Activities:Energy costs of human activities in adults aged 60 and older 被引量:6
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作者 Erik A.Willis Stephen D.Herrmann +8 位作者 Mary Hastert Chelsea L.Kracht Tiago V.Barreira John M.Schuna Jr. Zhenghua Cai Minghui Quan Scott A.Conger Wendy J.Brown Barbara E.Ainsworth 《Journal of Sport and Health Science》 SCIE CSCD 2024年第1期13-17,F0003,共6页
Purpose:To describe the development of a Compendium for estimating the energy costs of activities in adults>60 years(OA Compendium).Methods:Physical activities(PAs)and their metabolic equivalent of task(MET)values ... Purpose:To describe the development of a Compendium for estimating the energy costs of activities in adults>60 years(OA Compendium).Methods:Physical activities(PAs)and their metabolic equivalent of task(MET)values were obtained from a systematic search of studies published in 4 sport and exercise databases(PubMed,Embase,SPORTDiscus(EBSCOhost),and Scopus)and a review of articles included in the 2011 Adult Compendium that measured PA in older adults.MET values were computed as the oxygen cost(VO_(2),mL/kg/min)during PA divided by 2.7 m L/kg/min(MET_(60+))to account for the lower resting metabolic rate in older adults.Results:We identified 68 articles and extracted energy expenditure data on 427 PAs.From these,we derived 99 unique Specific Activity codes with corresponding MET_(60+)values for older adults.We developed a website to present the OA Compendium MET_(60+)values:https://pacompendium.com.Conclusion:The OA Compendium uses data collected from adults>60 years for more accurate estimation of the energy cost of PAs in older adults.It is an accessible resource that will allow researchers,educators,and practitioners to find MET_(60+)values for older adults for use in PA research and practice. 展开更多
关键词 energy expenditure EXERCISE MET Older adults
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Recent advances in graphene-based phase change composites for thermal energy storage and management 被引量:2
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作者 Qiang Zhu Pin Jin Ong +4 位作者 Si Hui Angela Goh Reuben J.Yeo Suxi Wang Zhiyuan Liu Xian Jun Loh 《Nano Materials Science》 EI CAS CSCD 2024年第2期115-138,共24页
Energy storage and conservation are receiving increased attention due to rising global energy demands.Therefore,the development of energy storage materials is crucial.Thermal energy storage(TES)systems based on phase ... Energy storage and conservation are receiving increased attention due to rising global energy demands.Therefore,the development of energy storage materials is crucial.Thermal energy storage(TES)systems based on phase change materials(PCMs)have increased in prominence over the past two decades,not only because of their outstanding heat storage capacities but also their superior thermal energy regulation capability.However,issues such as leakage and low thermal conductivity limit their applicability in a variety of settings.Carbon-based materials such as graphene and its derivatives can be utilized to surmount these obstacles.This study examines the recent advancements in graphene-based phase change composites(PCCs),where graphene-based nanostructures such as graphene,graphene oxide(GO),functionalized graphene/GO,and graphene aerogel(GA)are incorporated into PCMs to substantially enhance their shape stability and thermal conductivity that could be translated to better storage capacity,durability,and temperature response,thus boosting their attractiveness for TES systems.In addition,the applications of these graphene-based PCCs in various TES disciplines,such as energy conservation in buildings,solar utilization,and battery thermal management,are discussed and summarized. 展开更多
关键词 Phase change material NANOCOMPOSITES Solar energy Sustainable energy Thermo-regulation
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Metal-organic framework-based single-atom electro-/ photocatalysts: Synthesis, energy applications, and opportunities 被引量:3
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作者 Munir Ahmad Jiahui Chen +10 位作者 Jianwen Liu Yan Zhang Zhongxin Song Shahzad Afzal Waseem Raza Liaqat Zeb Andleeb Mehmood Arshad Hussain Jiujun Zhang Xian-Zhu Fu Jing-Li Luo 《Carbon Energy》 SCIE EI CAS CSCD 2024年第1期1-43,共43页
Single-atom catalysts(SACs)have gained substantial attention because of their exceptional catalytic properties.However,the high surface energy limits their synthesis,thus creating significant challenges for further de... Single-atom catalysts(SACs)have gained substantial attention because of their exceptional catalytic properties.However,the high surface energy limits their synthesis,thus creating significant challenges for further development.In the last few years,metal–organic frameworks(MOFs)have received significant consideration as ideal candidates for synthesizing SACs due to their tailorable chemistry,tunable morphologies,high porosity,and chemical/thermal stability.From this perspective,this review thoroughly summarizes the previously reported methods and possible future approaches for constructing MOF-based(MOF-derived-supported and MOF-supported)SACs.Then,MOF-based SAC's identification techniques are briefly assessed to understand their coordination environments,local electronic structures,spatial distributions,and catalytic/electrochemical reaction mechanisms.This review systematically highlights several photocatalytic and electrocatalytic applications of MOF-based SACs for energy conversion and storage,including hydrogen evolution reactions,oxygen evolution reactions,O_(2)/CO_(2)/N_(2) reduction reactions,fuel cells,and rechargeable batteries.Some light is also shed on the future development of this highly exciting field by highlighting the advantages and limitations of MOF-based SACs. 展开更多
关键词 carbon energy generation MOF-derived-supported MOF-supported single atoms
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Oxygen functionalization-assisted anionic exchange toward unique construction of flower-like transition metal chalcogenide embedded carbon fabric for ultra-long life flexible energy storage and conversion 被引量:1
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作者 Roshan M.Bhattarai Kisan Chhetri +5 位作者 Nghia Le Debendra Acharya Shirjana Saud Mai Cao Hoang Phuong Lan Nguyen Sang Jae Kim Young Sun Mok 《Carbon Energy》 SCIE EI CAS CSCD 2024年第1期72-93,共22页
The metal-organic framework(MOF)derived Ni–Co–C–N composite alloys(NiCCZ)were“embedded”inside the carbon cloth(CC)strands as opposed to the popular idea of growing them upward to realize ultrastable energy storag... The metal-organic framework(MOF)derived Ni–Co–C–N composite alloys(NiCCZ)were“embedded”inside the carbon cloth(CC)strands as opposed to the popular idea of growing them upward to realize ultrastable energy storage and conversion application.The NiCCZ was then oxygen functionalized,facilitating the next step of stoichiometric sulfur anion diffusion during hydrothermal sulfurization,generating a flower-like metal hydroxysulfide structure(NiCCZOS)with strong partial implantation inside CC.Thus obtained NiCCZOS shows an excellent capacity when tested as a supercapacitor electrode in a three-electrode configuration.Moreover,when paired with the biomass-derived nitrogen-rich activated carbon,the asymmetric supercapacitor device shows almost 100%capacity retention even after 45,000 charge–discharge cycles with remarkable energy density(59.4 Wh kg^(-1)/263.8μWh cm^(–2))owing to a uniquely designed cathode.Furthermore,the same electrode performed as an excellent bifunctional water-splitting electrocatalyst with an overpotential of 271 mV for oxygen evolution reaction(OER)and 168.4 mV for hydrogen evolution reaction(HER)at 10 mA cm−2 current density along with 30 h of unhinged chronopotentiometric stability performance for both HER and OER.Hence,a unique metal chalcogenide composite electrode/substrate configuration has been proposed as a highly stable electrode material for flexible energy storage and conversion applications. 展开更多
关键词 carbon cloth energy conversion energy storage FLEXIBLE metal embedding ultra-stable
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Co-Harvest Phase-Change Enthalpy and Isomerization Energy for High-Energy Heat Output by Controlling Crystallization of Alkyl-Grafted Azobenzene Molecules 被引量:1
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作者 Jian Gao Yiyu Feng +6 位作者 Wenyu Fang Hui Wang Jing Ge Xiaoyu Yang Huitao Yu Mengmeng Qin Wei Feng 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第3期415-424,共10页
Photoisomerization-induced phase change are important for co-harvesting the latent heat and isomerization energy of azobenzene molecules.Chemically optimizing heat output and energy delivery at alternating temperature... Photoisomerization-induced phase change are important for co-harvesting the latent heat and isomerization energy of azobenzene molecules.Chemically optimizing heat output and energy delivery at alternating temperatures are challenging because of the differences in crystallizability and isomerization.This article reports two series of asymmetrically alkyl-grafted azobenzene(Azo-g),with and without a methyl group,that have an optically triggered phase change.Three exothermic modes were designed to utilize crystallization enthalpy(△H_(c))and photothermal(isomerization)energy(△H_(p))at different temperatures determined by the crystallization.Azo-g has high heat output(275-303 J g^(-1))by synchronously releasing△H_(c)and△H_(p)over a wide temperature range(-79℃to 25℃).We fabricated a new distributed energy utilization and delivery system to realize a temperature increase of 6.6℃at a temperature of-8℃.The findings offer insight into selective utilization of latent heat and isomerization energy by molecular optimization of crystallization and isomerization processes. 展开更多
关键词 crystallizability distributed energy utilization system energy density exothermic modes ISOMERIZATION
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Significantly Improved High-Temperature Energy Storage Performance of BOPP Films by Coating Nanoscale Inorganic Layer 被引量:3
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作者 Tiandong Zhang Hainan Yu +5 位作者 Young Hoon Jung Changhai Zhang Yu Feng Qingguo Chen Keon Jae Lee Qingguo Chi 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第2期30-38,共9页
Biaxially oriented polypropylene(BOPP)is one of the most commonly used commercial capacitor films,but its upper operating temperature is below 105℃due to the sharply increased electrical conduction loss at high tempe... Biaxially oriented polypropylene(BOPP)is one of the most commonly used commercial capacitor films,but its upper operating temperature is below 105℃due to the sharply increased electrical conduction loss at high temperature.In this study,growing an inorganic nanoscale coating layer onto the BOPP film's surface is proposed to suppress electrical conduction loss at high temperature,as well as increase its upper operating temperature.Four kinds of inorganic coating layers that have different energy band structure and dielectric property are grown onto the both surface of BOPP films,respectively.The effect of inorganic coating layer on the high-temperature energy storage performance has been systematically investigated.The favorable coating layer materials and appropriate thickness enable the BOPP films to have a significant improvement in high-temperature energy storage performance.Specifically,when the aluminum nitride(AIN)acts as a coating layer,the AIN-BOPP-AIN sandwich-structured films possess a discharged energy density of 1.5 J cm^(-3)with an efficiency of 90%at 125℃,accompanying an outstandingly cyclic property.Both the discharged energy density and operation temperature are significantly enhanced,indicating that this efficient and facile method provides an important reference to improve the high-temperature energy storage performance of polymer-based dielectric films. 展开更多
关键词 coating layer energy storage interfacial barrier polymer films
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Dynamics and vibration reduction performance of asymmetric tristable nonlinear energy sink 被引量:4
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作者 Hongyan CHEN Youcheng ZENG +2 位作者 Hu DING Siukai LAI Liqun CHEN 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第3期389-406,共18页
With its complex nonlinear dynamic behavior,the tristable system has shown excellent performance in areas such as energy harvesting and vibration suppression,and has attracted a lot of attention.In this paper,an asymm... With its complex nonlinear dynamic behavior,the tristable system has shown excellent performance in areas such as energy harvesting and vibration suppression,and has attracted a lot of attention.In this paper,an asymmetric tristable design is proposed to improve the vibration suppression efficiency of nonlinear energy sinks(NESs)for the first time.The proposed asymmetric tristable NES(ATNES)is composed of a pair of oblique springs and a vertical spring.Then,the three stable states,symmetric and asymmetric,can be achieved by the adjustment of the distance and stiffness asymmetry of the oblique springs.The governing equations of a linear oscillator(LO)coupled with the ATNES are derived.The approximate analytical solution to the coupled system is obtained by the harmonic balance method(HBM)and verified numerically.The vibration suppression efficiency of three types of ATNES is compared.The results show that the asymmetric design can improve the efficiency of vibration reduction through comparing the chaotic motion of the NES oscillator between asymmetric steady states.In addition,compared with the symmetrical tristable NES(TNES),the ATNES can effectively control smaller structural vibrations.In other words,the ATNES can effectively solve the threshold problem of TNES failure to weak excitation.Therefore,this paper reveals the vibration reduction mechanism of the ATNES,and provides a pathway to expand the effective excitation amplitude range of the NES. 展开更多
关键词 ASYMMETRIC nonlinear energy sink(NES) tristable vibration control po-tential barrier
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Moderate Fields, Maximum Potential: Achieving High Records with Temperature‑Stable Energy Storage in Lead‑Free BNT‑Based Ceramics 被引量:1
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作者 Wenjing Shi Leiyang Zhang +7 位作者 Ruiyi Jing Yunyao Huang Fukang Chen Vladimir Shur Xiaoyong Wei Gang Liu Hongliang Du Li Jin 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第5期184-200,共17页
The increasing awareness of environmental concerns has prompted a surge in the exploration of leadfree,high-power ceramic capacitors.Ongoing efforts to develop leadfree dielectric ceramics with exceptional energystora... The increasing awareness of environmental concerns has prompted a surge in the exploration of leadfree,high-power ceramic capacitors.Ongoing efforts to develop leadfree dielectric ceramics with exceptional energystorage performance(ESP)have predominantly relied on multicomponent composite strategies,often accomplished under ultrahigh electric fields.However,this approach poses challenges in insulation and system downsizing due to the necessary working voltage under such conditions.Despite extensive study,bulk ceramics of(Bi_(0.5)Na_(0.5))TiO_(3)(BNT),a prominent lead-free dielectric ceramic family,have seldom achieved a recoverable energy-storage(ES)density(Wrec)exceeding 7 J cm^(−3).This study introduces a novel approach to attain ceramic capacitors with high ESP under moderate electric fields by regulating permittivity based on a linear dielectric model,enhancing insulation quality,and engineering domain structures through chemical formula optimization.The incorporation of SrTiO_(3)(ST)into the BNT matrix is revealed to reduce the dielectric constant,while the addition of Bi(Mg_(2/3)Nb_(1/3))O_(3)(BMN)aids in maintaining polarization.Additionally,the study elucidates the methodology to achieve high ESP at moderate electric fields ranging from 300 to 500 kV cm^(−1).In our optimized composition,0.5(Bi_(0.5)Na_(0.4)K_(0.1))TiO_(3)–0.5(2/3ST-1/3BMN)(B-0.5SB)ceramics,we achieved a Wrec of 7.19 J cm^(−3) with an efficiency of 93.8%at 460 kV cm^(−1).Impressively,the B-0.5SB ceramics exhibit remarkable thermal stability between 30 and 140℃ under 365 kV cm^(−1),maintaining a Wrec exceeding 5 J cm^(−3).This study not only establishes the B-0.5SB ceramics as promising candidates for ES materials but also demonstrates the feasibility of optimizing ESP by modifying the dielectric constant under specific electric field conditions.Simultaneously,it provides valuable insights for the future design of ceramic capacitors with high ESP under constraints of limited electric field. 展开更多
关键词 BNT energy storage LEAD-FREE Relaxor ferroelectrics Capacitors
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