检索结果-南通市图书馆

Free radicals trigger the closure of open pores in lignin-derived hard carbons toward improved sodium-storage capacity

引用

Journal of Energy Chemistry 2024年第7期94卷 551-559页

作者： Wen-Jun Ji Zong-Lin Yi Ming-Xin Song Xiao-Qian Guo Yi-Lin Wang Yi-Xuan Mao fang-yuan su Jing-Peng Chen Xian-Xian Wei Li-Jing Xie Cheng-Meng Chen CAS Key Laboratory of Carbon Materials Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001ShanxiChina University of Chinese Academy of Sciences Beijing 100049China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China School of Environment and Safety Taiyuan University of Science and TechnologyTaiyuan 030001ShanxiChina

The chemical activation of various precursors is effective for creating additional closed pores in hard carbons for sodium ***,the formation mechanism of closed pores under the influence of pore-forming agents is not well ***,an effective chemical activation followed by a high-temperature self-healing strategy is employed to generate interconnected closed pores in lignin-derived hard carbon(HCs).By systematic experimental design combined with electron paramagnetic res-onance spectroscopy,it can be found that the content of free radicals in the carbon matrix influences the closure of open pores at high *** high activation temperature(>700 C)leads to a low free radical concentration,making it difficult to achieve self-healing of open pores at high *** activation at 700°C,a balance between pore making and self-healing is achieved in the final hard carbon.A large number of free radicals triggers rapid growth and aggregation of carbon microcrys-tals,blocking pre-formed open micropores and creating additional interconnected closed pores in as-obtained hard *** a result,the optimized carbon anode(LK-700-1300)delivers a high reversible capacity of 330.8 mA h g^(-1) at 0.03 A g^(-1),which is an increase of 86 mA h g^(-1) compared to the pristine lignin-derived carbon anode(L-700-1300),and exhibits a good rate performance(202.1 mA h g^(-1) at 1 A g^(-1)).This work provides a universal and effective guidance for tuning closed pores of hard carbons from otherprecursors.

关键词： Hard carbon Chemical activation Free radical Self-healing Closed pores Sodium ion batteries

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Recent advances in transition metal chalcogenides for lithium-ion capacitors

引用

Rare Metals 2022年第9期41卷 2971-2984页

作者： Lei Wang Xiong Zhang Chen Li Xian-Zhong sun Kai Wang fang-yuan su fang-Yan Liu Yan-Wei Ma Institute of Electrical Engineering Chinese Academy of SciencesBeijing100190China School of Engineering Sciences University of Chinese Academy of SciencesBeijing100049China Institute of Electrical Engineering and Advanced Electromagnetic Drive Technology Qilu ZhongkeJinan250013China Dalian National Laboratory for Clean Energy Chinese Academy of SciencesDalian116023China CAS Key Laboratory of Carbon Materials Institute of Coal ChemistryChinese Academy of SciencesTaiyuan030001China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian116023China

Transition metal chalcogenides(TMCs)and TMCs-based nanocomposites have attracted extensive attention due to their versatile material species,low cost,and rich physical and chemical *** anode materials of lithium-ion capacitors(LICs),TMCs have exhibited high theoretical capacities and pseudocapacitance storage ***,there are many intrinsic challenges,such as low electrical conductivity,repeatedly high-volume changes and sluggish ionic diffusion ***,many traditional and unconventional techniques have been reported to solve these critical problems,and many innovative strategies are also used to prepare high quality anode materials for *** this mini review,a detailed family member list and comparison of TMCs in the field of lithium-ion capacitors have been summarized ***,many rectification stratagems and recent researches of TMCs have been exhibited and *** the end,as an outcome of these discussions,some further challenges and perspectives are envisioned to promote the application of TMCs materials for lithium-ion c apacitors.

关键词： Energy storage Transition metal chalcogenides(TMCs) Lithium-ion capacitors(LICs) Performance optimization

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Effect of N-doping-derived solvent adsorption on electrochemical double layer structure and performance of porous carbon

引用

Journal of Energy Chemistry 2023年第5期80卷 120-127,I0004页

作者： Zhe-Fan Wang Cheng Tang Qian sun Ya-Lu Han Zhi-Jian Wang Lijing Xie Shou-Chun Zhang fang-yuan su Cheng-Meng Chen CAS Key Laboratory of Carbon Materials Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001ShanxiChina University of Chinese Academy of Sciences Bejing 100049China Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical EngineeringTsinghua UniversityBejing 100084Chind

N-doped porous carbon has been extensively investigated for broad electrochemical *** performance is significantly impacted by the electrochemical double layer(EDL),which is material dependent and hard to *** understanding of doping-derived EDL structure hinders insight into the structure-performance relations and the rational design of high-performance ***,we analyzed the mass and chemical composition variation of EDL within electrochemical operation by electrochemical quartz crystal microbalance,in-situ X-ray photoelectron spectroscopy,and time-offlight secondary ion mass *** found that N-doping triggers specifically adsorbed propylene carbonate solvent in the inner Helmholtz plane(IHP),which prevents ion rearrangement and enhances the migration of ***,this specific adsorption accelerated solvent decomposition,rendering rapid performance degradation in practical *** work reveals that the surface chemistry of electrodes can cause specific adsorption of solvents and change the EDL structure,which complements the classical EDL theory and provide guidance for practical applications.

关键词： Carbon materials Electrochemical double layer Electrochemical quartz crystal microbalance In-situ X-ray photoelectron spectroscopy N-doping

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Molecular-scale controllable conversion of biopolymers into hard carbons towards lithium and sodium ion batteries: A review

引用

Journal of Energy Chemistry 2022年第9期31卷 554-569,I0016页

作者： Li-Jing Xie Cheng Tang Ming-Xin Song Xiao-Qian Guo Xiao-Ming Li Jing-Xue Li Chong Yan Qing-Qiang Kong Guo-Hua sun Qiang Zhang fang-yuan su Cheng-Meng Chen CAS Key Laboratory of Carbon Materials Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001ShanxiChina University of Chinese Academy of Sciences Beijing 100049China Bejing KeyLaboratory of Green Chemical Reaction Engineering and Technology.Department of Chemical Engineering.Tsinghua University Bejing 100084China School o Chemical Enginering and Advanced Materials The Universityof Adelaide.AdelaideSA 5005Ausralia Center of Biomass Enginering/Cllge of Agronomy and Biotechnology China Agriultural UniversiyBeijing 100193China

Hard carbons are widely investigated as potential anodes for lithium and sodium ion batteries owing to their internally well-tailored textures(closed pores and defects) and large microcrystalline interlayer spacing. The renewable biomass is a green and economically attractive carbon source to produce hard carbons. However, the chemical and structural complexity of biomass has plagued the understanding of evolution mechanism from organic precursors to hard carbons and the structure-property *** makes it difficult to finely tune the microstructure of biomass-derived hard carbons, thus greatly restricting their high-performance applications. Most recently, the optimal utilization and controllable conversion of biomass-derived biopolymers(such as starch, cellulose and lignin) at the molecular level have become a burgeoning area of research to develop hard carbons for advanced *** the principal source of carbonaceous materials is from biomass pyrolysis, we firstly overview the chemical structures and pyrolysis behaviors of three main biopolymers. Then, the controllable preparation of hard carbons using various physicochemical properties of biopolymers at the molecular level is systematically discussed. Furthermore, we highlight present challenges and further opportunities in this field. The Review will guide future research works on the design of sustainable hard carbons and the optimization of battery performance.

关键词： Biomass-derived biopolymers Hard carbons Lithium ion batteries Sodium ion batteries Carbonization

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Relationships between blood chromium exposure and liver injury:Exploring the mediating role of systemic inflammation in a chromate-exposed population

引用

Journal of Environmental Sciences 2024年第9期143卷 224-234页

作者： Zekang su Yali Zhang Shiyi Hong Qiaojian Zhang Jiayu Xu Guiping Hu Xiaojun Zhu fang yuan Shanfa Yu Tianchen Wang Guang Jia Department of Occupational and Environmental Health Sciences School of Public HealthPeking UniversityBeijing 100191China School of Engineering Medicine and Beijing Advanced Innovation Center for Big Data-Based Precision Medicine Beihang UniversityBeijing 100191China National Center for Occupational Safety and Health Beijing 102308China Department of Occupational Health and Radiological Health Chongqing Centers for Disease Control and PreventionChongqing 400042China Henan Institute for Occupational Medicine Zhengzhou 450052China Department of Clinical Laboratory Third Hospital of Peking UniversityBeijing 100191China

Hexavalent chromium and its compounds are prevalent pollutants,especially in the work environment,pose a significant risk for multisystem toxicity and *** it is known that chromium accumulation in the liver can cause damage,the dose-response relationship between blood chromium(Cr)and liver injury,as well as the possible potential toxic mechanisms involved,remains poorly *** address this,we conducted a follow-up study of 590 visits from 305 participants to investigate the associations of blood Cr with biomarkers for liver injury,including serum alanine aminotransferase(ALT),aspartate aminotransferase(AST),total bilirubin(TBIL),and direct bilirubin(DBIL),and to evaluate the mediating effects of systemic ***(PLT)and the platelet-to-lymphocyte ratio(PLR)were utilized as biomarkers of systemic *** the linear mixed-effects analyses,each 1-unit increase in blood Cr level was associated with estimated effect percentage increases of 0.82%(0.11%,1.53%)in TBIL,1.67%(0.06%,3.28%)in DBIL,0.73%(0.04%,1.43%)in ALT and 2.08%(0.29%,3.87%)in AST,***,PLT mediated 10.04%,11.35%,and 10.77%increases in TBIL,DBIL,and ALT levels induced by chromate,*** addition,PLR mediated 8.26%and 15.58%of the association between blood Cr and TBIL or *** findings shed light on the mechanisms underlying blood Cr-induced liver injury,which is partly due to worsening systemic inflammation.

关键词： Blood chromate Liver injury Systemic inflammation Mediation analysis

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Adaptive Algorithms on Maximizing Monotone Nonsubmodular Functions

引用

Journal of the Operations Research Society of China 2024年第2期12卷 428-445页

作者： Bin Liu Hui su Shu-fang Gong Qi-Zhi fang School of Mathematical Sciences Ocean Universityof ChinaQingdao266100ShandongChina

submodular optimization is widely used in large *** order to speed up the problems solving,it is essential to design low-adaptive algorithms to achieve acceleration in *** general,the function values are given by a value oracle,but in practice,the oracle queries may consume a lot of ***,how to strike a balance between optimizing them is *** this paper,we focus on maximizing a normalized and strictly monotone set function with the diminishing-return ratio under a cardinality constraint,and propose two algorithms to deal with *** apply the adaptive sequencing technique to devise the first algorithm,whose approximation ratio is arbitrarily close to 1-e^(-γ)in O(logn·log(log(k\γ))adaptive rounds,and requires O(logn^(2)·log(log(k\γ))*** by adding preprocessing and parameter estimation steps to the first algorithm,we get the second *** second algorithm trades a small sacrifice in adaptive complexity for a significant improvement in query *** the same approximation and adaptive complexity,the query complexity is improved *** the best of our knowledge,this is the first paper of designing adaptive algorithms for maximizing a monotone function using the diminishing-return ratio.

关键词： Approximation algorithm Adaptivity Nonsubmodular maximization:Cardinality constraint

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Generalized Newton-Busemann Law for Two-dimensional Steady Hypersonic-limit Euler Flows Passing Ramps with Skin-frictions

引用

Acta Mathematicae Applicatae Sinica 2024年

作者： Ai-fang QU Xue-ying su Hai-rong yuan School of Mathematical Sciences Key Laboratory of Mathematics and Engineering Applications (Ministry of Education) & Shanghai Key Laboratory of PMMP East China Normal University School of Mathematics and Statistics Xi'an Jiaotong University Department of Mathematics Shanghai Normal University

By considering Radon measure solutions for boundary value problems of stationary non-isentropic compressible Euler equations on hypersonic-limit flows passing ramps with frictions on their boundaries, we construct solutions with density containing Dirac measures supported on the boundaries of the ramps, which represent the infinite-thin shock layers under different assumptions on the skin-frictions. We thus derive corresponding generalizations of the celebrated Newton-Busemann law in hypersonic aerodynamics for distributions of drags/lifts on ramps.

关键词：

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Data-driven discovery of linear dynamical systems from noisy data

引用

Science China(Technological Sciences) 2024年第1期67卷 121-129页

作者： WANG YaSen yuan Ye fang HuaZhen DING Han School of Mechanical Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China State Key Lab of Digital Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China School of Artificial Intelligence and Automation Huazhong University of Science and TechnologyWuhan 430074China Department of Mechanical Engineering University of KansasLawrence 66045USA

In modern science and engineering disciplines,data-driven discovery methods play a fundamental role in system modeling,as data serve as the external representations of the intrinsic mechanisms within ***,empirical data contaminated by process and measurement noise remain a significant obstacle for this type of *** this study,we have developed a data-driven method capable of directly uncovering linear dynamical systems from noisy *** method combines the Kalman smoothing and sparse Bayesian learning to decouple process and measurement noise under the expectation-maximization framework,presenting an analytical method for alternate state estimation and system ***,the discovered model explicitly characterizes the probability distribution of process and measurement noise,as they are essential for filtering,smoothing,and stochastic *** have successfully applied the proposed algorithm to several simulation *** results demonstrate its potential to enable linear dynamical system discovery in practical applications where noise-free data are intractable to capture.

关键词： system identification sparse Bayesian learning Kalman smoothing process and measurement noise

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Energy-Efficient Driving Strategy for High-Speed Trains with Considering the Checkpoints

引用

Chinese Journal of Electronics 2024年第3期33卷 847-858页

作者： Zixuan ZHANG yuan CAO Shuai su State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University School of Electronic and Information Engineering Beijing Jiaotong University National Engineering Research Center of Rail Transportation Operation and Control System Beijing Jiaotong University Frontiers Science Center for Smart High-speed Railway System Beijing Jiaotong University

With rising energy prices and concerns about environmental issues,energy-efficient driving strategies(EEDS) for high-speed trains have received a substantial amount of *** particular,energy-saving schemes play a huge role in reducing the energy and operating costs of *** article studies the EEDS of high-speed trains at a given time.A well-posed model is formulated,in which the constraints of the checkpoints,in addition to the speed limits,vehicle dynamics,and discrete control throttle,are first *** a given control sequence,the Karush-Kuhn-Tucker(KKT) conditions are used to obtain the necessary conditions for an *** to several key equations of the necessary conditions,the checkpoint constraints are *** case studies are conducted based on the data of the Beijing-Shanghai high-speed line to illustrate the effectiveness of the proposed approach.

关键词： Energy consumption Costs Simulation Mathematical models Energy efficiency Vehicle dynamics Optimization

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Photonic neuromorphic architecture for tens-of-task lifelong learning

引用

Light(Science & Applications) 2024年第3期13卷 519-530页

作者： yuan Cheng Jianing Zhang Tiankuang Zhou Yuyan Wang Zhihao Xu Xiaoyun yuan Lu fang Sigma Laboratory Department of Electronic EngineeringTsinghua UniversityBeijing 100084China Beijing National Research Center for Information Science and Technology(BNRist) Beijing 100084China Institute for Brain and Cognitive Science Tsinghua University(THUIBCS)Beijing 100084China

Scalable,high-capacity,and low-power computing architecture is the primary assurance for increasingly manifold and large-scale machine learning *** electronic artificial agents by conventional power-hungry processors have faced the issues of energy and scaling walls,hindering them from the sustainable performance improvement and iterative multi-task *** to another modality of light,photonic computing has been progressively applied in high-efficient neuromorphic ***,we innovate a reconfigurable lifelong-learning optical neural network(L2 ONN),for highly-integrated tens-of-task machine intelligence with elaborated algorithm-hardware *** from the inherent sparsity and parallelism in massive photonic connections,L2 ONN learns each single task by adaptively activating sparse photonic neuron connections in the coherent light field,while incrementally acquiring expertise on various tasks by gradually enlarging the *** multi-task optical features are parallelly processed by multi-spectrum representations allocated with different *** evaluations on freespace and on-chip architectures confirm that for the first time,L2 ONN avoided the catastrophic forgetting issue of photonic computing,owning versatile skills on challenging tens-of-tasks(vision classification,voice recognition,medical diagnosis,etc.)with a single ***,L2 ONN achieves more than an order of magnitude higher efficiency than the representative electronic artificial neural networks,and 14×larger capacity than existing optical neural networks while maintaining competitive performance on each individual *** proposed photonic neuromorphic architecture points out a new form of lifelong learning scheme,permitting terminal/edge AI systems with light-speed efficiency and unprecedented scalability.

关键词： life neural versatile

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：