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一种可级联的多通道实时阵列信号处理系统设计
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作者 冯武 罗欣 孙卫杰 《现代电子技术》 北大核心 2024年第7期25-32,共8页
随着数字波束形成(DBF)体制雷达的集成度要求越来越高,分体式信号处理系统架构已经很难满足要求。为了解决此问题,文中提出一种可级联的多通道实时阵列信号处理系统。首先,在同一块阵列信号处理板上采用24路的模数转换器(ADC)、现场可... 随着数字波束形成(DBF)体制雷达的集成度要求越来越高,分体式信号处理系统架构已经很难满足要求。为了解决此问题,文中提出一种可级联的多通道实时阵列信号处理系统。首先,在同一块阵列信号处理板上采用24路的模数转换器(ADC)、现场可编程逻辑门阵列(FPGA)、数字信号处理器(DSP)等芯片,实现多通道ADC采样、下变频、波束控制、数字波束形成、信号处理等功能;然后,通过高速GTH总线、系统同步、系统校准、多级流水等技术实现级联不同数量的阵列信号处理板,可应用于不同规模的DBF体制雷达。 展开更多
关键词 数字波束形成 多级流水 系统同步 系统校准 FPGA DSP
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Boosting rate performance of layered lithium-rich cathode materials by oxygen vacancy induced surface multicomponent integration
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作者 Youyou Fang Yuefeng Su +7 位作者 Jinyang Dong Jiayu Zhao Haoyu Wang Yun Lu Bin Zhang Hua Yan feng wu Lai Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期250-262,共13页
The rapid development of electric vehicles and portable energy storage systems demands improvements in the energy density and cost-effectiveness of lithium-ion batteries,a domain in which Lithium-rich layered cathode(... The rapid development of electric vehicles and portable energy storage systems demands improvements in the energy density and cost-effectiveness of lithium-ion batteries,a domain in which Lithium-rich layered cathode(LLO)materials inherently excel.However,these materials face practical challenges,such as low initial Coulombic efficiency,inferior cycle/rate performance,and voltage decline during cycling,which limit practical application.Our study introduces a surface multi-component integration strategy that incorporates oxygen vacancies into the pristine LLO material Li1.2Mn_(0.6)Ni_(0.2)O_(2).This process involves a brief citric acid treatment followed by calcination,aiming to explore rate-dependent degradation behavior.The induced surface oxygen vacancies can reduce surface oxygen partial pressure and diminish the generation of O_(2)and other highly reactive oxygen species on the surface,thereby facilitating the activation of Li ions trapped in tetrahedral sites while overcoming transport barriers.Additionally,the formation of a spinel-like phase with 3D Li+diffusion channels significantly improves Li^(+)diffusion kinetics and stabilizes the surface structure.The optimally modified sample boasts a discharge capacity of 299.5 mA h g^(-1)at a 0.1 C and 251.6 mA h g^(-1)at a 1 C during the initial activation cycle,with an impressive capacity of 222.1 mA h g^(-1)at a 5 C.Most notably,it retained nearly 70%of its capacity after 300 cycles at this elevated rate.This straightforward,effective,and highly viable modification strategy provides a crucial resolution for overcoming challenges associated with LLO materials,making them more suitable for practical application. 展开更多
关键词 Lithium-ion battery Layered lithium rich cathode Surface multicomponent integration Rate-dependent degradation and Li^(+) diffusion kinetics
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Evolution of the porous structure for phosphoric acid etching carbon as cathodes in Li–O_(2) batteries:Pyrolysis temperature-induced characteristics changes
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作者 Feiyang Yang Ying Yao +6 位作者 Yunkai Xu Cong Wang Meiling Wang Jingjie Ren Cunzhong Zhang feng wu Jun Lu 《Carbon Energy》 SCIE EI CAS CSCD 2024年第1期172-181,共10页
Although biomass-derived carbon(biochar)has been widely used in the energy field,the relation between the carbonization condition and the physical/chemical property of the product remains elusive.Here,we revealed the ... Although biomass-derived carbon(biochar)has been widely used in the energy field,the relation between the carbonization condition and the physical/chemical property of the product remains elusive.Here,we revealed the carbonization condition's effect on the morphology,surface property,and electrochemical performance of the obtained carbon.An open slit pore structure with shower-puff-like nanoparticles can be obtained by finely tuning the carbonization temperature,and its unique pore structure and surface properties enable the Li–O_(2) battery with cycling longevity(221 cycles with 99.8%Coulombic efficiency at 0.2 mA cm^(−2) and controlled discharge–charge depths of 500 mAh g^(−1))and high capacity(16,334 mAh g^(−1) at 0.02 mA cm^(−2)).This work provides a greater understanding of the mechanism of the biochar carbonization procedure under various pyrolysis conditions,paving the way for future study of energy storage devices. 展开更多
关键词 BIOMASS Li-O_(2) battery oxygen catalysts porous carbon temperature parameters
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Metal-organic frameworks and their composites for advanced lithium-ion batteries:Synthesis,progress and prospects
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作者 Chengcai Liu Borong wu +7 位作者 Tao Liu Yuanxing Zhang Jingwen Cui Lingjun Huang Guoqiang Tan Ling Zhang Yuefeng Su feng wu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第2期449-470,I0011,共23页
Metal-organic frameworks(MOFs)are among the most promising materials for lithium-ion batteries(LIBs)owing to their high surface area,periodic porosity,adjustable pore size,and controllable chemical composition.For ins... Metal-organic frameworks(MOFs)are among the most promising materials for lithium-ion batteries(LIBs)owing to their high surface area,periodic porosity,adjustable pore size,and controllable chemical composition.For instance,their unique porous structures promote electrolyte penetration,ions transport,and make them ideal for battery separators.Regulating the chemical composition of MOF can introduce more active sites for electrochemical reactions.Therefore,MOFs and their related composites have been extensively and thoroughly explored for LIBs.However,the reported reviews solely include the applications of MOFs in the electrode materials of LIBs and rarely involve other aspects.A systematic review of the application of MOFs in LIBs is essential for understanding the mechanism of MOFs and better designing related MOFs battery materials.This review systematically evaluates the latest developments in pristine MOFs and MOF composites for LIB applications,including MOFs as the main materials(anode,cathode,separators,and electrolytes)to auxiliary materials(coating layers and additives for electrodes).Furthermore,the synthesis,modification methods,challenges,and prospects for the application of MOFs in LIBs are discussed. 展开更多
关键词 Metal-organic frameworks ELECTRODES Electrolytes SEPARATORS Lithium-ion batteries
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基于FPGA的多功能阵列信号处理系统设计 被引量:1
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作者 罗欣 冯武 +1 位作者 孙卫杰 刘马良 《电子科技》 2023年第3期1-6,共6页
为了适应阵列信号处理数据量大、实时性高的特点,文中结合项目需求设计了一种基于FPGA的多功能阵列信号处理系统。通过采用先进的大规模高性能FPGA和多路高精度ADC芯片,可完成对40路中频信号的同步采集和数字下变频处理,并由数字波束合... 为了适应阵列信号处理数据量大、实时性高的特点,文中结合项目需求设计了一种基于FPGA的多功能阵列信号处理系统。通过采用先进的大规模高性能FPGA和多路高精度ADC芯片,可完成对40路中频信号的同步采集和数字下变频处理,并由数字波束合成运算得到36组波束数据。通过设置多种类型的对外接口,可实现与多个外联设备的网络数据交互、串口控制、波束控制及MGT高速数据传输。文中给出了系统的硬件和软件总体架构设计,并详细介绍了芯片选型、外设接口及各软件功能模块的具体实现方法。测试结果表明,本系统满足设计需求,具有较强的阵列信号处理能力以及良好的通用性和可扩展性。 展开更多
关键词 多功能 阵列信号处理 FPGA ADC 数字下变频 数字波束合成 波束控制 高速传输
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面向低空预警雷达的信号处理控制平台设计与实现 被引量:1
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作者 罗欣 冯武 孙卫杰 《现代雷达》 CSCD 北大核心 2023年第2期75-80,共6页
为应对以民用无人机为代表的低小慢目标“黑飞”“滥飞”所带来的低空安全威胁以及巡航导弹、战术导弹所带来的低空军事威胁,文中引入数字波束合成技术,设计并实现了一种面向低空预警雷达的信号处理控制平台,该平台具有实时性强、运算... 为应对以民用无人机为代表的低小慢目标“黑飞”“滥飞”所带来的低空安全威胁以及巡航导弹、战术导弹所带来的低空军事威胁,文中引入数字波束合成技术,设计并实现了一种面向低空预警雷达的信号处理控制平台,该平台具有实时性强、运算量大、传输速率高等特点。通过选用高速光纤传输与串行总线VPX技术,同时采用高性能模数转换器、超大规模现场可编程门阵列及高速专用数字信号处理芯片,实现了此平台的硬件架构设计,并在此平台上实现了一种基于数据流驱动的软件信号处理方案。得益于灵活的系统架构和丰富的硬件资源,该信号处理控制平台可以适应新技术的快速应用,便于低空预警雷达功能的升级扩展及性能的进一步提升,有效应对低空威胁。 展开更多
关键词 低空预警雷达 信号处理控制平台 数字波束合成 高速交换网络 数据流驱动
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基于高通量测序与培养基鉴定法分析不同省份不同养殖模式下小龙虾菌群的多样性 被引量:1
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作者 范鹏飞 冯武 +3 位作者 肖瑶 张月洁 杜红英 陈加平 《食品工业科技》 CAS 北大核心 2023年第1期181-188,共8页
本研究以安徽霍邱、江苏盱眙、湖北荆州三地的小龙虾作为研究对象,在荆州另取稻虾互作和养殖塘两种模式的环境样本。利用高通量技术做菌相分析,利用培养基鉴定法进行分离纯化鉴定,验证优势菌种类和数量。结果表明:荆州两组小龙虾初始菌... 本研究以安徽霍邱、江苏盱眙、湖北荆州三地的小龙虾作为研究对象,在荆州另取稻虾互作和养殖塘两种模式的环境样本。利用高通量技术做菌相分析,利用培养基鉴定法进行分离纯化鉴定,验证优势菌种类和数量。结果表明:荆州两组小龙虾初始菌数略低于盱眙和霍邱小龙虾,选择培养基上差别较小。高通量测序结果表明,科水平上三地小龙虾的优势菌主要为气单胞菌科和肠杆菌科;稻虾塘土壤菌群丰度远高于养殖塘,水体菌群较相似。属水平上,荆州稻虾塘、养殖塘、盱眙和霍邱四组小龙虾样本菌群丰度存在差异,但气单胞菌属和不动杆菌属都占较高比例,依次为41.8%、1.8%,12.4%、11.4%,24.5%、27.5%,40.1%,13.0%。荆州稻虾塘小龙虾优势菌还包括乳球菌属和柠檬酸杆菌属,养殖塘样本存在哈夫尼亚菌属和乳球菌属,盱眙与霍邱小龙虾样本优势菌均有微小杆菌属和柠檬酸杆菌属。培养基结果表明三地小龙虾优势菌均主要为气单胞菌属、哈夫尼亚菌属和柠檬酸杆菌属,与高通量结果相符。 展开更多
关键词 高通量测序 小龙虾菌群 优势菌种 环境菌群 稻虾共作
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Highly Reversible Zn Metal Anodes Enabled by Increased Nucleation Overpotential 被引量:2
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作者 Zhengqiang Hu fengling Zhang +8 位作者 Anbin Zhou Xin Hu Qiaoyi Yan Yuhao Liu Faiza Arshad Zhujie Li Renjie Chen feng wu Li Li 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第10期197-209,共13页
Dendrite formation severely compromises further development of zinc ion batteries. Increasing the nucleation overpotential plays a crucial role in achieving uniform deposition of metal ions. However, this strategy has... Dendrite formation severely compromises further development of zinc ion batteries. Increasing the nucleation overpotential plays a crucial role in achieving uniform deposition of metal ions. However, this strategy has not yet attracted enough attention from researchers to our knowledge. Here, we propose that thermodynamic nucleation overpotential of Zn deposition can be boosted through complexing agent and select sodium L-tartrate(Na-L) as example. Theoretical and experimental characterization reveals L-tartrate anion can partially replace H_(2)O in the solvation sheath of Zn^(2+), increasing de-solvation energy. Concurrently, the Na^(+) could absorb on the surface of Zn anode preferentially to inhibit the deposition of Zn^(2+) aggregation. In consequence, the overpotential of Zn deposition could increase from 32.2 to 45.1 mV with the help of Na-L. The Zn-Zn cell could achieve a Zn utilization rate of 80% at areal capacity of 20 mAh cm^(-2). Zn-LiMn_(2)O_(4) full cell with Na-L additive delivers improved stability than that with blank electrolyte. This study also provides insight into the regulation of nucleation overpotential to achieve homogeneous Zn deposition. 展开更多
关键词 Nucleation overpotential Complexing agent Zn batteries Zn deposition
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Double spatial confinement on ruthenium nanoparticles inside carbon frameworks as durable catalysts for a quasi-solid-state Li–O_(2) battery 被引量:1
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作者 Meiling Wang Ying Yao +5 位作者 Feiyang Yang Zhenwu Tang Jingjie Ren Cunzhong Zhang feng wu Xiangke Wang 《Carbon Energy》 SCIE CSCD 2023年第8期114-125,共12页
The rational design of large-area exposure,nonagglomeration,and longrange dispersion of metal nanoparticles(NPs)in the catalysts is critical for the development of energy storage and conversion systems.Little attentio... The rational design of large-area exposure,nonagglomeration,and longrange dispersion of metal nanoparticles(NPs)in the catalysts is critical for the development of energy storage and conversion systems.Little attention has been focused on modulating and developing catalyst interface contact engineering between a carbon substrate and dispersed metal.Here,a highly dispersed ultrafine ruthenium(Ru)NP strategy by double spatial confinement is proposed,that is,incorporating directed growth of metal–organic framework crystals into a bacterial cellulose templating substrate to integrate their respective merits as an excellent electrocatalytic cathode catalyst for a quasi-solid-state Li–O_(2) battery.The porous carbon matrix with highly dispersed ultrafine Ru NPs is well designed and used as cathode catalysts in a Li–O_(2) battery,demonstrating a high discharge areal capacity of 6.82 mAh cm^(–2) at 0.02 mA cm^(–2),a high-rate capability of 4.93 mAh cm^(–2) at 0.2 mA cm^(–2),and stable discharge/charge cycling for up to 500 cycles(2000 h)with low overpotentials of~1.4 V.This fundamental understanding of the structure–performance relationship demonstrates a new and promising approach to optimize highly efficient cathode catalysts for solid-state Li–O_(2) batteries. 展开更多
关键词 bacterial cellulose cathode materials metal-organic frameworks Ru nanoparticles solid-state Li-O_(2)batteries
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Numerical and experimental study on the particle erosion and gas–particle hydrodynamics in an integral multi-jet swirling spout-fluidized bed
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作者 Wenbin Li feng wu +2 位作者 Liuyun Xu Jipeng Sun Xiaoxun Ma 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第9期90-101,共12页
In this paper,using the computational fluid dynamics based on Euler Lagrange and the commercial software Barracuda VR,the gas-particle hydrodynamics and the erosion of particles on the inner wall and internal componen... In this paper,using the computational fluid dynamics based on Euler Lagrange and the commercial software Barracuda VR,the gas-particle hydrodynamics and the erosion of particles on the inner wall and internal components of the spouted bed in the integrated multi-jet swirling spout-fluidized bed(IMSSFB)are studied.Erosion experiments have obtained the characterization of particle erosion on internal components and verified the relevant numerical models.The results show that:the particle distribution within the IMSSFB is uneven due to the cyclonic effect of the axial swirl vane(ASV),resulting in particle erosion for the ASV being concentrated on one side;when the gas reaches the top,too high an erosion gas velocity leads to gas backflow.As the filling height increases,there is a tendency for the erosion position of the particles on the ASV to expand upwards.However,the effect of increasing gas velocity on the erosion position is insignificant. 展开更多
关键词 Integral multi-jet swirling spout-fluidized bed Gas–particle hydrodynamics Axial swirl vane Uneven Erosion
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Progress in research of process intensification of spouted beds:A comprehensive review
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作者 Jiali Du feng wu Xiaoxun Ma 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第10期238-260,共23页
The development of intensification technology for spouted beds has become a current research focus,and an effective way to improve the efficiency of spouted beds is to reform their structure.Although numerous studies ... The development of intensification technology for spouted beds has become a current research focus,and an effective way to improve the efficiency of spouted beds is to reform their structure.Although numerous studies have been conducted on conventional beds,there are few reviews on the comprehensive application of intensification technology for spouted beds.In this paper,we comprehensively review the role of intensification technology in spouted beds for use in hydrodynamics,drying,desulfurization,pyrolysis,coating,biomass and waste gasification,and biomass drying from the perspective of experiment and simulation.Finally,potential problems and challenges in current spouted-bed research are summarized. 展开更多
关键词 Spouted bed Intensification technology DRYING DESULFURIZATION PYROLYSIS
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Reversible cationic-anionic redox in disordered rocksalt cathodes enabled by fluorination-induced integrated structure design
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作者 feng wu Jinyang Dong +9 位作者 Jiayu Zhao Qi Shi Yun Lu Ning Li Duanyun Cao Wenbo Li Jianan Hao Yu Zheng Lai Chen Yuefeng Su 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第7期158-169,I0004,共13页
Cation-disordered rocksalt oxides(DRX)have been identified as promising cathode materials for high energy density applications owing to their variable elemental composition and cationic-anionic redox activity.However,... Cation-disordered rocksalt oxides(DRX)have been identified as promising cathode materials for high energy density applications owing to their variable elemental composition and cationic-anionic redox activity.However,their practical implementation has been impeded by unwanted phenomena such as irrepressible transition metal migration/dissolution and O_(2)/CO_(2)evolution,which arise due to parasitic reactions and densification-degradation mechanisms during extended cycling.To address these issues,a micron-sized DRX cathode Li_(1.2)Ni_(1/3)Ti_(1/3)W_(2/15)O_(1.85)F_(0.15)(SLNTWOF)with F substitution and ultrathin LiF coating layer is developed by alcohols assisted sol-gel method.Within this fluorination-induced integrated structure design(FISD)strategy,in-situ F substitution modifies the activity/reversibility of the cationic-anionic redox reaction,while the ultrathin LiF coating and single-crystal structure synergistically mitigate the cathode/electrolyte parasitic reaction and densification-degradation mechanism.Attributed to the multiple modifications and size effect in the FISD strategy,the SLNTWOF sample exhibits reversible cationic-anionic redox chemistry with a meliorated reversible capacity of 290.3 mA h g^(-1)at 0.05C(1C=200 mA g^(-1)),improved cycling stability of 78.5%capacity retention after 50 cycles at 0.5 C,and modified rate capability of 102.8 mA h g^(-1)at 2 C.This work reveals that the synergistic effects between bulk structure modification,surface regulation,and engineering particle size can effectively modulate the distribution and evolution of cationic-anionic redox activities in DRX cathodes. 展开更多
关键词 Cation-disordered rocksalt oxides Fluorine substitution Ultrathin LiF coating Micron-sized single-crystal Reversible cationic-anionic redox
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Stable cycling of LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2)/lithium metal batteries enabled by synergistic tuning the surface stability of cathode/anode
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作者 Chunli Li Xinyu Zhang +8 位作者 Zhuolin Yang Haijian Lv Tinglu Song Shijie Lu Yuxiang Zhang Tianwen Yang Fan Xu feng wu Daobin Mu 《Journal of Energy Chemistry》 SCIE EI CSCD 2023年第12期342-350,I0009,共10页
Ni-rich layered oxides(LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2))show great potential in long-range and low-cost lithiumion batteries.However,due to the high surface sensitivity,their practical application is hindered by inte... Ni-rich layered oxides(LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2))show great potential in long-range and low-cost lithiumion batteries.However,due to the high surface sensitivity,their practical application is hindered by interfacial instability with electrolytes under high voltage for long cyclic life.Herein,by combining both firstprinciple calculations and time-of-flight secondary ion mass spectrometry(TOF-SIMS),a novel surface fluorinated reconstruction(SFR)mechanism is proposed to improve the interfacial stability under high voltage,which could effectively regulate the surface fluoride species to desensitize the LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2)interface.We demonstrate here that by tuning the ratio of fluoride species,the LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2)/Li battery could achieve excellent long-term and high voltage performance(163.5 mA h g^(-1)at 0.5 C for 300 cycles under 4.4 V),while the controlled sample decayed to 125.4 mA h g^(-1)after 300 cycles.Moreover,the favorable cross-talk effect induced by SFR further facilitates the incorporation of suitable amounts of Ni ions into the construction of stable solid electrolyte interface(SEI)layer for anode surface.Therefore,the ultra-long cycling stability under high voltage can be achieved by the robust cathode/electrolyte and Li/electrolyte interfaces,which results in excellent interfacial stability after long cycling.This work provides new insights into the surface design of cathode materials and improves the stability of the electrode-electrode interface under high voltage. 展开更多
关键词 Ni-rich layered oxides Surface fluorinated reconstruction Interfacial stability TOF-SIMS Cross-talk effect
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全固态钠离子电池硫系化合物电解质 被引量:9
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作者 陈光海 白莹 +2 位作者 高永晟 吴锋 吴川 《物理化学学报》 SCIE CAS CSCD 北大核心 2020年第5期44-62,共19页
全固态钠离子电池具有资源丰富、安全性高等优势,作为未来大规模储能的重要选择而成为近年来先进二次电池前沿研究热点。钠离子硫系化合物电解质室温离子电导率高、弹性模量高、容易冷压成型,能增强电极/电解质界面接触、减小界面阻抗... 全固态钠离子电池具有资源丰富、安全性高等优势,作为未来大规模储能的重要选择而成为近年来先进二次电池前沿研究热点。钠离子硫系化合物电解质室温离子电导率高、弹性模量高、容易冷压成型,能增强电极/电解质界面接触、减小界面阻抗、缓冲电极材料在充放电过程中的应力/应变,是全固态钠离子电池的研究重点。本文对钠离子硫系化合物固态电解质的结构及性质进行了总结,讨论了硫系化合物电解质的本征特性、与电极的界面稳定性,并介绍了硫系化合物全固态钠离子电池的研究现状,最后分析了硫系化合物电解质面临的挑战及今后的发展方向。 展开更多
关键词 全固态钠离子电池 硫系化合物电解质 电导率 化学稳定性 界面
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高镍正极材料中钴元素的替代方案及其合成工艺优化 被引量:6
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作者 吴锋 李晴 +6 位作者 陈来 王紫润 陈刚 包丽颖 卢赟 陈实 苏岳锋 《物理化学学报》 SCIE CAS CSCD 北大核心 2022年第5期60-69,共10页
高镍三元正极材料LiNi_(x)Mn_(y)Co_(1−x−y)O_(2)(x>0.8)因其高能量密度而备受瞩目。在高镍三元正极材料中,Co不但有助于增强层状正极材料结构稳定性,而且能够提高正极材料导电性能,因此被认为是一种非常重要的元素。但是由于目前全... 高镍三元正极材料LiNi_(x)Mn_(y)Co_(1−x−y)O_(2)(x>0.8)因其高能量密度而备受瞩目。在高镍三元正极材料中,Co不但有助于增强层状正极材料结构稳定性,而且能够提高正极材料导电性能,因此被认为是一种非常重要的元素。但是由于目前全球范围内钴矿资源紧缺,在一定程度上限制了含钴正极材料在新能源电动汽车领域的发展应用。基于此,本文将不同的过渡金属离子掺杂到高镍层状材料中形成无钴化正极材料,并进行高镍正极材料无钴化的可行性分析。通过实验对比发现,资源存储量丰富并且价格低廉的Zr在一定程度上可以取代Co元素,得到的正极材料LiNi_(0.85)Mn_(0.1)Zr_(0.05)O_(2)表现出良好的电化学性能,在0.2C倍率以及2.75–4.3 V的截止电压范围内,其放电比容量为179.9 mAh·g^(−1),80周容量保持率为96.52%。 展开更多
关键词 锂离子电池 高镍正极材料 无钴化 循环性能
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内镜与显微镜下经单侧鼻蝶入路手术切除垂体腺瘤的效果和对T淋巴细胞亚群的影响 被引量:7
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作者 牛国栋 袁明智 +3 位作者 孙青青 吴锋 申桃瑞 任洪波 《中国内镜杂志》 2021年第10期52-61,共10页
目的探讨内镜与显微镜下经单侧鼻蝶入路手术治疗垂体腺瘤的效果。方法选取2018年10月-2020年10月该院垂体腺瘤患者112例,依据随机数表法分为内镜组与显微镜组,每组各56例。内镜组采取内镜下单侧鼻蝶入路手术,显微镜组采取显微镜下经单... 目的探讨内镜与显微镜下经单侧鼻蝶入路手术治疗垂体腺瘤的效果。方法选取2018年10月-2020年10月该院垂体腺瘤患者112例,依据随机数表法分为内镜组与显微镜组,每组各56例。内镜组采取内镜下单侧鼻蝶入路手术,显微镜组采取显微镜下经单侧鼻蝶入路手术。统计两组患者肿瘤切除效果、手术情况、T淋巴细胞亚群指标、应激反应指标[肾素(R)、血管紧张素Ⅱ(ATⅡ)、肾上腺素(E)、去甲肾上腺素(NE)]、生存质量和并发症发生率。结果内镜组肿瘤全切率(91.07%)高于显微镜组(76.79%)(P<0.05),手术时间和住院时间较显微镜组短,术中失血量较显微镜组少,住院费用较显微镜组少(P<0.05),术后1和3 d内镜组CD3^(+)、CD4^(+)、CD4^(+)/CD8^(+)水平较显微镜组高,血清R、ATⅡ、E和NE水平较显微镜组低(P<0.05),术后1周内镜组鼻部相关生存质量评分较显微镜组低(P<0.05),内镜组并发症发生率(5.36%)较显微镜组(17.86%)低(P<0.05)。结论与显微镜下经单侧鼻蝶入路手术相比,内镜下手术治疗垂体腺瘤具有肿瘤切除效果好、患者术后恢复快等优势,可减轻应激反应及缓解免疫抑制,值得临床推广。 展开更多
关键词 内镜 显微镜 单侧鼻蝶入路 垂体腺瘤 T淋巴细胞亚群 生存质量 经济性
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江苏宿迁台断层气CO_(2)浓度特征及影响因素分析
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作者 孙煜杰 彭澎 +2 位作者 张荣杉 冯武 张朋 《四川地震》 2023年第2期18-22,共5页
选用江苏宿迁台2021年4月1日至11月26日观测数据,分析断层气CO_(2)浓度与地质构造、土壤覆盖层及气象等因素的关系。研究结果显示:宿迁台断层气CO_(2)测点位置优良,高值出现在每年的10、11月,低值出现在每年的1、2月,7月的观测值有轻微... 选用江苏宿迁台2021年4月1日至11月26日观测数据,分析断层气CO_(2)浓度与地质构造、土壤覆盖层及气象等因素的关系。研究结果显示:宿迁台断层气CO_(2)测点位置优良,高值出现在每年的10、11月,低值出现在每年的1、2月,7月的观测值有轻微下降趋势,8—11月的观测值有上升趋势;断层气CO_(2)浓度变化主要受气压和降雨量影响,与气压呈正相关性,具有较好的同步性,与降水关系密切,由于降水会阻碍地下气体的运移和释放,从而影响观测数据的稳定性,出现突跳或台阶,导致测值不能真正反映测点CO_(2)的释放情况。通过对干扰因素及特征的研究,丰富了断层气观测手段,为研究宿迁市及郯庐断裂带中段的断裂活动与断层气关系积累资料。 展开更多
关键词 断层气 CO_(2) 地震监测 影响因素 宿迁台
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动态增强磁共振成像对初诊鼻咽癌患者调强放疗预后的评估价值 被引量:4
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作者 孟彬彬 张蕾 +1 位作者 吴锋 缪世军 《中国现代医学杂志》 CAS 北大核心 2022年第17期14-20,共7页
目的研究动态增强磁共振成像(DCE-MRI)对初诊鼻咽癌患者调强放射治疗(IMRT)预后的评估价值。方法选取2016年1月—2021年12月南通市第二人民医院收治的82例初诊鼻咽癌患者,均行IMRT。IMRT前行DCE-MRI检查,计算K^(trans)值、K_(ep)值、V_... 目的研究动态增强磁共振成像(DCE-MRI)对初诊鼻咽癌患者调强放射治疗(IMRT)预后的评估价值。方法选取2016年1月—2021年12月南通市第二人民医院收治的82例初诊鼻咽癌患者,均行IMRT。IMRT前行DCE-MRI检查,计算K^(trans)值、K_(ep)值、V_(e)值、V_(p)值。IMRT结束后3个月根据临床疗效将患者分为良好组52例,不良组30例,比较良好组与不良组IMRT前的DCE-MRI参数及临床资料;采用多因素逐步Logistic回归分析IMRT预后不良的危险因素;绘制受试者工作特征(ROC)曲线,评价DCE-MRI参数对初诊鼻咽癌患者IMRT预后的预测价值。结果不良组IMRT前K^(trans)、K_(ep)较良好组缩短(P<0.05);不良组贫血,原发灶大小为超腔,T分期为T_(3)、T_(4),咽后淋巴结转移较良好组升高(P<0.05);Logistic回归分析结果显示,贫血[OR=1.732(95%CI:1.269,2.194)],原发灶大小为超腔[OR=1.489(95%CI:1.254,1.724)],咽后淋巴结转移[OR=2.659(95%CI:2.013,3.305)],T分期为T_(3)、T_(4)[OR=3.504(95%CI:1.987,5.022)],K^(trans)[OR=5.865(95%CI:3.145,8.585)]和K_(ep)[OR=3.142(95%CI:2.412,3.873)]均为初诊鼻咽癌IMRT患者预后不良的危险因素(P<0.05)。ROC结果显示,K^(trans)预测初诊鼻咽癌IMRT患者预后不良的最佳截断值为0.22 min,AUC为0.728(95%CI:0.618,0.820),敏感性为80.00%(95%CI:0.754,0.846),特异性为82.69%(95%CI:0.792,0.862);K_(ep)预测初诊鼻咽癌患者IMRT预后不良的最佳截断值为0.71 min,AUC为0.746(95%CI:0.637,0.835),敏感性为76.67%(95%CI:0.698,0.836),特异性为75.00%(95%CI:0.671,0.829);两者联合预测预后不良的AUC为0.762(95%CI:0.655,0.849),敏感性为76.67%(95%CI:0.712,0.821),特异性88.46%(95%CI:0.804,0.965)。结论DCE-MRI中K^(trans)、K_(ep)对初诊鼻咽癌患者IMRT预后具有一定预测价值,可为临床个体化治疗及治疗方案的修正提供依据。 展开更多
关键词 鼻咽癌 动态增强磁共振成像 调强放疗 预后
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徐香猕猴桃多酚抗氧化特性研究 被引量:8
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作者 卜凡琼 代雨婷 +1 位作者 冯武 彭帮柱 《华中农业大学学报》 CAS CSCD 北大核心 2019年第1期112-118,共7页
以徐香猕猴桃(Actinidia chinensis)为试验材料,测定其总酸度、总糖和维生素C的含量;采用超声提取法提取猕猴桃多酚,测定猕猴桃多酚的总还原能力及对羟基自由基、超氧自由基、DPPH自由基、ABTS自由基等4种自由基的清除能力,并以Vc为对照... 以徐香猕猴桃(Actinidia chinensis)为试验材料,测定其总酸度、总糖和维生素C的含量;采用超声提取法提取猕猴桃多酚,测定猕猴桃多酚的总还原能力及对羟基自由基、超氧自由基、DPPH自由基、ABTS自由基等4种自由基的清除能力,并以Vc为对照,评价徐香猕猴桃多酚的抗氧化特性。结果显示,徐香猕猴桃总酸、总糖及Vc含量分别为1.13%±0.16%、10.03%±0.78%及(78.71±7.60)mg/100g,猕猴桃提取液的多酚质量浓度为0.123mg/mL。猕猴桃多酚的总还原能力高于Vc,猕猴桃多酚对4种自由基清除率的IC50值均比Vc的IC50值低,表明猕猴桃多酚具有很高的抗氧化活性。猕猴桃多酚中含有没食子酸、香豆酸、儿茶素、绿原酸、咖啡酸、阿魏酸等6种多酚类物质,其中咖啡酸含量最高,其次为绿原酸、香豆酸、儿茶素,阿魏酸和没食子酸含量较少。 展开更多
关键词 猕猴桃 多酚 抗氧化 自由基 总还原能力
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从泡菜中分离的植物乳杆菌P51降解亚硝酸盐影响因素的动态研究 被引量:5
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作者 苏容容 熊蝶 +2 位作者 袁岚玉 冯武 陈加平 《中国调味品》 CAS 北大核心 2020年第3期27-32,共6页
从泡菜中分离得到一株植物乳杆菌P51,研究了在不同温度、不同NaCl含量、不同亚硝酸盐浓度以及不同培养基起始pH下其降解亚硝酸盐的动态变化和培养液pH值的改变。结果表明:植物乳杆菌P51能够有效降解培养基中的亚硝酸盐,其最适降解温度... 从泡菜中分离得到一株植物乳杆菌P51,研究了在不同温度、不同NaCl含量、不同亚硝酸盐浓度以及不同培养基起始pH下其降解亚硝酸盐的动态变化和培养液pH值的改变。结果表明:植物乳杆菌P51能够有效降解培养基中的亚硝酸盐,其最适降解温度为37℃,最适NaCl含量为4%,最适亚硝酸盐浓度为200μg/mL,最适起始pH为6,同时植物乳杆菌P51高效降解亚硝酸盐可能主要依靠酸降解。该菌株表现出良好的耐食盐和亚硝酸盐特性,可作为良好的乳酸菌发酵剂,对于应用到泡菜和腌制肉制品中具有很大的潜力。 展开更多
关键词 植物乳杆菌 亚硝酸盐 PH 降解
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