检索结果-南通市图书馆

Degradation analysis and doping modification optimization for high-voltage P-type layered cathode in sodium-ion batteries

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2024年第2期89卷 1-9,I0002页

作者： bao Zhang Yi Zhao minghuang Li Qi Wang lei Cheng lei ming Xing Ou Xiaowei Wang National Engineering Laboratory for High-Efficiency Recovery of Refractory Nonferrous metals School of Metallurgy and EnvironmentCentral South UniversityChangsha 410083HunanChina Zhejiang Power New Energy Co. LTDZhuji 311800ZhejiangChina

Advancing high-voltage stability of layered sodium-ion oxides represents a pivotal avenue for their progress in energy storage *** this,a comprehensive understanding of the mechanisms underpinning their structural deterioration at elevated voltages remains insufficiently *** this study,we unveil a layer delamination phenomenon of Na_(0.67)Ni_(0.3)mn_(0.7)O_(2)(NNm)within the 2.0-4.3 V voltage,attributed to considerable volumetric fluctuations along the c-axis and lattice oxygen reactions induced by the simultaneous Ni^(3+)/Ni^(4+)and anion redox *** introducing mg doping to diminished Ni-O antibonding,the anion oxidation-reduction reactions are effectively mitigated,and the structural integrity of the P2 phase remains firmly intact,safeguarding active sites and precluding the formation of novel *** Na_(0.67)mg_(0.05)Ni_(0.25)mn_(0.7)O_(2)(NmNm-5)exhibits a specific capacity of100.7 mA h g^(-1),signifying an 83%improvement compared to the NNm material within the voltage of2.0-4.3 *** investigation underscores the intricate interplay between high-voltage stability and structural degradation mechanisms in layered sodium-ion oxides.

关键词： Soidum ion batteries Layer cathode materials P-type High-voltage performance Degradation analysis

molecular engineering binuclear copper catalysts for selective CO_(2) reduction to C_(2) products

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2024年第6期93卷 166-173,I0005页

作者： Qi Zhao Kai lei bao Yu Xia Rachel Crespo-Otero Devis Di Tommaso Department of Chemistry School of Physical and Chemical SciencesQueen Mary University of LondonLondonE14NSUK Key Laboratory of material Chemistry for Energy Conversion and Storage(ministry of Education) Hubei Key Laboratory of Material Chemistry and Service FailureState Key Laboratory of Materials Processing and Die&Mould TechnologySchool of Chemistry and Chemical EngineeringHuazhong University of Science and Technology(HUST)Wuhan 430074HubeiChina Department of Chemistry University College LondonLondonWC1H 0AJUK Digital Environment Research Institute Queen Mary University of LondonEmpire HouseLondon E11HHUK

molecular copper catalysts serve as exemplary models for correlating the structure-reaction-mechanism relationship in the electrochemical CO_(2) reduction(eCO_(2)R),owing to their adaptable environments surrounding the copper metal *** investigation,employing density functional theory calculations,focuses on a novel family of binuclear Cu molecular *** modulation of their coordination configuration through the introduction of organic groups aims to assess their efficacy in converting CO_(2) to C_(2)*** findings highlight the crucial role of chemical valence state in shaping the characteristics of binuclear Cu catalysts,consequently influencing the eCO_(2)R behaviour,Notably,the Cu(Ⅱ)Cu(Ⅱ)macrocycle catalyst exhibits enhanced suppression of the hydrogen evolution reaction(HER),facilitating proton trans fer and the eCO_(2)R *** rthermore,we explo re the impact of diverse electro n-withdrawing and electron-donating groups coordinated to the macrocycle(R=-F,-H,and-OCH_3)on the electron distribution in the molecular *** placement of-OCH_3 groups in the macrocycles leads to a favourable oxidation state of the Cu centres and subsequent C-C coupling to form C_(2) *** research provides fundamental insights into the design and optimization of binuclear Cu molecular catalysts for the electrochemical conversion of CO_(2) to value-added C_(2) products.

关键词： molecular catalyst design Selective CO_(2)reduction C_(2)products Density functional theory calculations

Remediation of di(2-ethylhexyl)phthalate(DEHP)contaminated black soil by freeze-thaw aging biochar

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2024年第1期135卷 681-692页

作者： lei Wang Zeyu Dou Chaoran ma Xiaochen Jia Hongye Wang Wenjing bao lei Wang Jianhua Qu Ying Zhang School of Resources and Environment Northeast Agricultural UniversityHarbin 150030China

Di(2-ethylhexyl)phthalate(DEHP),a complex structure with high toxicity,is a common organic *** study investigated the effects of fresh biochar(FBC),and freeze-thaw cycled aged biochar(FTC-BC)on DEHP-contaminated soils using a pot *** specific surface area of FBC increased from 145.20 to 303.50 m~2/g,and oxygen-containing functional groups increased from 1.26 to 1.48 mol/g after freeze-thaw cycles,greatly enhancing the adsorption of DEHP by biochar in the *** comprehensive radar chart evaluation showed that FBC and FTC-BC reduced DEHP growth stress and improved the soil *** with FBC,FTC-BC performed better in protecting the normal growth of pakchoi and improving soil *** addition,the application of biochar increased the diversity and abundance of bacteria in the DEHP-contaminated soil and changed the composition of the soil bacterial *** partial least squares path model(PLS-Pm)showed that adding biochar as a soil remediation agent significantly positively impacted soil nutrients and indirectly reduced the DEHP levels in soil and plants by increasing soil microbial *** with FBC,FTC-BC creates a more satisfactory living environment for microorganisms and has a better effect on the degradation of DEHP in the *** study provides a theoretical basis for future biochar remediation of DEHP-contaminated soils in cold high-latitude regions.

关键词： DEHP Freeze-thaw cycles Biochar Soil restoration

Reinforcement learning based edge computing in B5G

在线全文

学校读者我要写书评

暂无评论

Digital Communications and Networks 2024年第1期10卷 1-6页

作者： Jiachen Yang Yiwen Sun Yutian lei Zhuo Zhang Yang Li Yongjun bao Zhihan Lv School of Electrical and Information Engineering Tianjin UniversityTianjin300072China Technology and Data Center ***Beijing100176China School of Data Science and Software Engineering Qingdao UniversityQingdao266101China

The development of communication technology will promote the application of Internet of Things,and Beyond 5G will become a new technology *** the same time,Beyond 5G will become one of the important supports for the development of edge computing *** paper proposes a communication task allocation algorithm based on deep reinforcement learning for vehicle-to-pedestrian communication scenarios in edge *** trial and error learning of agent,the optimal spectrum and power can be determined for transmission without global information,so as to balance the communication between vehicle-to-pedestrian and *** results show that the agent can effectively improve vehicle-to-infrastructure communication rate as well as meeting the delay constraints on the vehicle-to-pedestrian link.

关键词： Reinforcement learning Edge computing Beyond 5G Vehicle-to-pedestrian

metal-Organic Framework Enabling Poly(Vinylidene Fluoride)-Based Polymer Electrolyte for Dendrite-Free and Long-Lifespan Sodium metal Batteries

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Energy & Environmental materials 2024年第1期7卷 68-76页

作者： Yusi lei Liang Yue Yuruo Qi Yubin Niu Shujuan bao Jie Song maowen Xu Faculty of materials and Energy Institute for Clean Energy&Advanced MaterialsSouthwest UniversityChongqing 400715China Shandong Zero-One-Four Advanced materials Co. Ltd.Feicheng 271099China

Sodium dentrite formed by uneven plating/stripping can reduce the utilization of active sodium with poor cyclic stability and,more importantly,cause internal short circuit and lead to thermal runaway and ***,sodium dendrites and their related problems seriously hinder the practical application of sodium metal batteries(SmBs).Herein,a design concept for the incorporation of metal-organic framework(mOF)in polymer matrix(polyvinylidene fluoride-hexafluoropropylene)is practiced to prepare a novel gel polymer electrolyte(PH@mOF polymer-based electrolyte[GPE])and thus to achieve high-performance *** addition of the mOF particles can not only reduce the movement hindrance of polymer chains to promote the transfer of Na^(+)but also anchor anions by virtue of their negative charge to reduce polarization during electrochemical reaction.A stable cycling performance with tiny overpotential for over 800 h at a current density of 5 mA cm^(-2)with areal capacity of 5 mA h cm^(-2)is achieved by symmetric cells based on the resulted GPE while the Na_(3)V_(2)O_(2)(PO_(4))_(2)F@rGO(NVOPF)|PH@mOF|Nacell also displays impressive specific cycling capacity(113.3 mA h g^(-1)at 1 C)and rate capability with considerable capacity retention.

关键词： dendrite-free gel polymer electrolyte metal organic framework sodium batteries

Effects of rare earth elements on inclusions, microstructure and impact toughness of spring steel

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2024年第4期31卷 933-944页

作者： Chun-lei Hao Chao-yun Yang Peng Liu Yi-kun Luan bao-guang Sang Shenyang National Laboratory for materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016LiaoningChina School of mechanical Engineering and Automation Dalian Polytechnic UniversityDalian 116034LiaoningChina

Spring steel is an indispensable basic part manufacturing material in mechanical equipment,which is widely used in transportation tools such as automobiles,railways,construction machinery and other *** effects of rare earth(RE)on inclusions,microstructure,carbides and impact toughness of 50CrV spring steel were studied by means of optical microscope,scanning electron microscope,transmission electron microscope and impact *** results show that the addition of rare earth can modify the main mnS and Al_(2)O_(3) inclusions in steel to form spherical or near-spherical rare earth inclusions,and the size of inclusions is significantly *** the quenched structure,the size of martensite slab becomes smaller and the structure is *** tempering,the carbide changes from sheet to ellipse,which makes it easier for spring steel to form stress concentration cracks under *** becomes finer and more dispersed,which leads to better pinning of grain boundaries and smaller grain *** impact toughness of 50CrV-RE spring steel increased from 21 to 41 J by 95%due to the improvement of inclusions,microstructure and carbides by rare *** is possible to improve the strength and toughness of spring steel for the improvement of railway running speed and the development of vehicle lightweight in China.

关键词： Rare earth-Spring steel Inclusion microstructure Impact toughness

New process for treating boron-bearing iron ore by flash reduction coupled with magnetic separation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of minerals,metallurgy and materials 2024年第3期31卷 473-484页

作者： Qipeng bao lei Guo Hong Yong Sohn Haibin Zuo Feng Liu Yongliang Gao Zhancheng Guo State Key Laboratory of Advanced metallurgy University of Science and Technology BeijingBeijing 100083China Department of materials Science&Engineering University of UtahUtah 84112USA China ENFI Engineering Corporation Beijing 100038China

Boron is an important industrial raw material often sourced from minerals containing different compounds that cocrystallize,which makes it difficult to separate the mineral phases through conventional *** study proposed a new treatment called flash reduction-melting separation(FRmS)for boron-bearing iron *** this method,the concentrates were first flash-reduced at the temperature under which the particles melt,and the slag and the reduced iron phases disengaged at the particle *** reduc-tion and melting effects were achieved above 1550℃.The B_(2)O_(3) content in the separated slag was over 18wt%,and the B content in the iron was less than 0.03wt%.The proposed FRmS method was tested to investigate the effects of factors such as ore particle size and tem-perature on the reduction and melting steps with and without pre-reducing the raw *** mineral phase transformation and morphology evolution in the ore particles during FRmS were also comprehensively analyzed.

关键词： ludwigite boron-bearing iron concentrate flash reduction melting separation boron

Inflection Point Age in the middle and Older Women—Jiangxi Province,China,2020-2022

在线全文

学校读者我要写书评

暂无评论

China CDC weekly 2024年第9期6卷 162-167页

作者： Shanlan Yang Langlang Zhang Helang Huang Jiaofeng Wang lei Wu Zhijun bao Shanghai Institute of Infectious Disease and Biosecurity Fudan UniversityShanghaiChina Department of Gerontology Huadong Hospital Affiliated to Fudan UniversityShanghai Key Laboratory of Clinical Geriatric MedicineResearch Center on Aging and MedicineFudan UniversityShanghaiChina Jiangxi Provincial Key Laboratory of Preventive medicine School of Public HealthNanchang UniversityNanchang CityJiangxi ProvinceChina

Summary What is already known about this topic?Previous studies have predominantly examined the micro-level aspects of women aging inflection points,while macro-level research using big data on the inflection points o... 详细信息

关键词： middle Jiangxi currently

Synthesis and characterization of high entropy(TiVNbTam)_(2)AlC(m=Zr,Hf)ceramics

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Advanced Ceramics 2024年第2期13卷 237-246页

作者： lei Cao Qiqiang Zhang Lijing Du Shuai Fu Detian Wan Yiwang bao Qingguo Feng Chunfeng Hu Key Laboratory of Advanced Technologies of materials Ministry of EducationSchool of Materials Science and EngineeringSouthwest Jiaotong UniversityChengdu 610031China State Key Laboratory of Green Building materials China Building Materials AcademyBeijing 100024China

The high-entropy design of mAX phases is expected to confer superior properties,but its study was hindered by the complex synthesis method and limited purity of *** this work,two noteworthy types of high-entropy mAX phase structural ceramics,high-entropy(TiVNbTam)_(2)AlC(m=Zr,Hf),were designed and prepared by the in-situ synthesis using spark plasma sintering(SPS).The microstructure and lattice parameters of sintered samples were *** with the single-component mAX phases,the highly pure high-entropy(TiVNbTaZr)_(2)AlC sample had good physical and mechanical properties,including electrical conductivity of 0.96×106Ω^(-1)·m^(-1),thermal expansion coefficient of 3.65×10^(-6) K^(-1),thermal conductivity of 8.98 W·m^(-1)·K^(-1),Vickers hardness of 9.80 GPa,flexural strength of 507 mPa,fracture toughness of 5.62 mPa·m^(1/2),and compressive strength of 1364 mPa,which exhibited the remarkable hardening-strengthening effect.

关键词： mAX phase high-entropy ceramic microstructure physical properties mechanical properties