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高温淬火对钠离子电池锰基层状正极材料结构和性能的影响

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储能科学与技术 2024年第7期13卷 2399-2406页

作者：谭仕荣尹文骥曾翠鸿黎小琼訚硕纪方力胡思江王红强李庆余湖南中伟新能源科技有限公司湖南长沙410699 广西师范大学化学与药学学院广西低碳能源材料重点实验室广西桂林541004

作为钠离子电池正极材料,锰基层状氧化物具有理论储钠容量高、成本低和热稳定性高等优点,但也存在因结构畸变、Na^(+)/空位有序以及过渡金属空位等带来的循环稳定性问题。研究表明,抑制过渡金属空位可有效提升锰基层状氧化物正极的电化... 详细信息

作为钠离子电池正极材料,锰基层状氧化物具有理论储钠容量高、成本低和热稳定性高等优点,但也存在因结构畸变、Na^(+)/空位有序以及过渡金属空位等带来的循环稳定性问题。研究表明,抑制过渡金属空位可有效提升锰基层状氧化物正极的电化学性能。为此,本工作对比研究了溶胶凝胶制备过程中高温淬火对Na_(0.67)Fe1/3Co_(1/3)Mn_(1/3)O_(2)(NFCMO)结构和性能的影响。结果表明,相比于未经高温淬火处理的NFCMO,高温液氮淬火合成的NFCMO-LN具有更高的比容量和倍率性能。NFCMO和NFCMO-LN在0.1C下的初始放电比容量分别为91.1 m Ah/g和129.8 m Ah/g;1C倍率下循环100周后的容量保留率分别为100%和90%。即使在10C的高倍率下,NFCMO-LN仍能提供56.2 m Ah/g的放电比容量。结构分析表明,高温液氮淬火能有效抑制过渡金属空位的产生,提升了材料的结构稳定性。研究结果为钠离子电池正极材料的结构设计和电化学性能优化提供了一种可行的技术途径。

关键词：钠离子电池层状氧化物锰酸钠掺杂淬火

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Mg,Ti-base surface integrated layer and bulk doping to suppress lattice oxygen evolution of Ni-rich cathode material at a high cut-off voltage

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Journal of Energy Chemistry 2022年第8期31卷 434-444,I0012页

作者： Fan Peng Youqi Chu Yu li Qichang Pan Guangchang Yang lixuan Zhang Sijiang Hu Fenghua Zheng Hongqiang Wang qingyu li Guangxi Key Laboratory of Low Carbon Energy Materials School of Chemistry and Pharmaceutical SciencesGuangxi Normal UniversityGuilin 541004GuangxiChina Guangxi New Energy Ship Battery Engineering Technology Research Center Guangxi Normal UniversityGuilin 541004GuangxiChina

The Nickel-rich layered cathode materials charged to 4.5 V can obtain a specific capacity of more than 200 m Ah g^(-1).However,the nickel-rich layered cathode materials suffer from the severe capacity fade during high-voltage cycling,which is related to the phase transformation and the surface sides reactions caused by the lattice oxygen ***,the simultaneous construction of a Mg,Ti-based surface integrated layer and bulk doping through Mg,Ti surface treatment could suppress the lattice oxygen evolution of Nirich material at deep *** importantly,Mg and Ti are co-doped into the particles surface to form an Mg_(2)TiO_(4) and Mg_(0.5–x)Ti_(2–y)(PO_(4))_(3) outer layer with Mg and Ti *** the constructed surface integrated layer,the reverse electric field in the Mg_(2)TiO_(4) effectively suppressed the outward migration of the lattice oxygen anions,while Mg_(0.5–x)Ti_(2–y)(PO_(4))_(3) outer layer with high electronic conductivity and good lithium ion conductor could effectively maintained the stability of the reaction interface during highvoltage ***,bulk Mg and Ti co-doping can mitigate the migration of Ni ions in the bulk to keep the stability of transition metal–oxygen(M-O)bond at deep *** a result,the NCM@MTP cathode shows excellent long cycle stability at high-voltage charging,which keep high capacity retention of 89.3%and 84.3%at 1 C after 200 and 100 cycles under room and elevated temperature of 25 and 55°C,*** work provides new insights for manipulating the surface chemistry of electrode materials to suppress the lattice oxygen evolution at high charging voltage.

关键词： Ni-rich layered oxide Mg Ti-base surface integrated layer Bulk doping Lattice oxygen evolution

Discharge voltage behavior of electric double-layer capacitors during high-g impact and their application to autonomously sensing high-g accelerometers

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Nano Research 2018年第2期11卷 1146-1156页

作者： Keren Dai Xiaofeng Wang Fang Yi Yajiang Yin Cheng Jiang Simiao Niu qingyu li Zheng You Collaborative Innovation Center for Micro/Nano Fabrication Device and System Tsinghua University Beijing China State Key Laboratory of Precision Measurement Technology and Instruments Tsinghua University Beijing China Department of Precision Instrument Tsinghua University Beijing China College of Chemistry and Molecular Engineering Peking University Beijing China School of Chemical Engineering Stanford University Stanford USA Department of Electronic Engineering Tsinghua University Beijing China

In this study, the discharge voltage behavior of electric double-layer capacitors （EDLCs） during high-g impact is studied both theoretically and experimentally. A micro-scale dynamic mechanism is proposed to describe the physical basis of the increase in the discharge voltage during a high-g impact. Based on this dynamic mechanism, a multi-field model is established, and the simulation and experimental studies of the discharge voltage increase phenomenon are conducted. From the simulation and experimental data, the relationship between the increased voltage and the high-g acceleration is revealed. An acceleration detection range of up to 10,000g is verified. The design of the device is optimized by studying the influences of the parameters, such as the electrode thickness and discharge current, on the outputs. This work opens up new avenues for the development of autonomous sensor systems based on energy storage devices and is significant for many practical applications such as in collision testing and automobile safety.

关键词： electric double-layercapacitor high-g acceleration autonomous sensor dynamic model

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反应堆压力容器一体化进出口接管结构优化

一重技术 2024年第4期 5-10页

作者：陈珉芮颜达鹏李青宇胡甜王点中国核动力研究设计院四川成都610200

为适应核反应堆小型化发展需求,提出四种一体化进、出口接管方案,采用数值模拟方法,分析流场特征,从降低流体压降角度出发,优化一体化进、出口接管结构。

关键词：反应堆压力容器小型化一体化进出口接管结构优化

Advanced all-solid-state lithium-selenium batteries enabled by selenium-nitrogen doped hierarchic meso-microporous carbon nanospheres composite cathode

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中国化学快报:英文版 2023年第9期34卷 289-293页

作者： Chongxing li Renbo liu Shuxian Zhang qingyu li Cong Wang Zhiwei Zhang Chengxiang Wang Longwei Yin Rutao Wang Key Laboratory for liquid-Solid Structural Evolution and Processing of Materials Ministry of EducationSchool of Materials Science and EngineeringShandong UniversityJi’nan 250061China

Selenium,an element belonging to the same group in the periodic table as sulfur,has a high electronic conductivity(1×10^(-5)S/cm)and a high volumetric energy density(3253 mA h/cm^(3)),which is a prospective cathode material for high-energy all-solid-state rechargeable ***,its wide use is hindered by large volume expansion and low utilization *** this work,Se-infused nitrogen-doped hierarchical meso-microporous carbon composites(Se/NHPC)are prepared by a melt-diffusion *** Se is uniformly dispersed in meso-micropores of NHPC with a high mass loading of 81%.All-solid-state li-Se batteries fabricated by using Se/NHPC as the cathode,a li-In alloy as the anode,and li_(6)PS_(5)Cl as the solid-state electrolyte,deliver a highly reversible capacity of 621 m Ah/g(92%of theoretical capacity),a good rate capability and a high capacity retention value of 80.9%after 100 *** is found that the capacity decay of Se cathode is mainly related to the interfacial degradation and the separation of Se from the carbon substrate,as suggested by the continuous increase of interfacial resistance and the structural transformation from amorphous Senchains to Se8rings initial discharge/charge cycle and then to the trigonally crystalline Se chains structure after the long-term cycles.

关键词： L-Se battery Solid-state electrolyte Carbon nanospheres li_(6)PS_(5)Cl Composite

Spinal cord injury in patients with systemic lupus Erythematosus Clinical manifestations, imaging characteristics and treatment

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Neural Regeneration Research 2007年第3期2卷 179-182页

作者： Yamei Tang Fusheng Zhang qingyu Shen Xiangpen li Yigang Xing Department of Neurology Second Affiliated Hospital of Sun Yat-sen University Guangzhou 510120 Guangdong Province China

BACKGROUND： There are fewer reports on systemic lupus erythematosus （SLE） related myelitis, and definite and uniform therapeutic program is not available. OBJECTIVE： To observe the clinical manifestations, imaging characteristics, results of laboratory examination and treatment of SLE. DESIGN： A retrospective case analysis. SETTING： Department of Neurology, the Second Affiliated Hospital of Sun Yat-sen University. PARTICIPANTS： Totally 1 052 SLE inpatients were selected from the Second Affiliated Hospital of Sun Yat-sen University from January 1995 to May 2005, and they all accorded with the diagnostic standards for SLE set by American Rheumatism Association in 1982. 124 of them were diagnosed to have damage of central nervous system. Inclusive criteria： Patients with one of the focal physical signs, including mental and behavior disorders, headache, seizure and involvement of nervous system. Exclusive criteria： Patients with hypertensive encephalopathy, damage of nervous system due to uremia and infection of central nervous system. Spinal cord lesion occurred in 15 female cases of 23 - 51 years old. Informed consents were obtained from all the participants. METHODS： The physical signs, laboratory examinations, therapeutic program and prognosis were recorded in the 15 patients with symptoms of spinal cord lesions. All the patients underwent MRI scan of brain or lesioned segment of spinal cord, and 8 cases of them underwent lumbar puncture to determine intracranial pressure, routine and biochemical examinations were cerebrospinal fluid were performed. The disease activity of SLE in systems beyond central nervous system was evaluated with modified lupus activity criteria count （LACC）. MAIN OUTCOME MEASURES：① Incidence of SLE related myelitis, attack age distribution and its association with the activity of SLE; ② Comparisons of the clinical characteristics, cranial and spinal cord MRI manifestations, different therapeutic program and prognosis. RESULTS： All the 15 SLE

关键词： systemic lupus erythematosus (SLE) myelitis magnetic resonance imaging (MRI)

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基于图谱资源构建目录服务的方法

火力与指挥控制 2024年第7期49卷 169-172,179页

作者：纪恩怀刘思培侯海婷严乐天王鹏飞李清玉北方信息控制研究院集团有限公司南京211100

随着信息技术的迅捷发展,军事信息系统采集与接入数据的来源和种类呈指数级增长。海量多源异构的多模态数据存在难以耦合、对作战用户的高价值信息密度低的问题。通过构建军事信息知识图谱可以有效集成各类数据,挖掘数据之间的耦合点和... 详细信息

随着信息技术的迅捷发展,军事信息系统采集与接入数据的来源和种类呈指数级增长。海量多源异构的多模态数据存在难以耦合、对作战用户的高价值信息密度低的问题。通过构建军事信息知识图谱可以有效集成各类数据,挖掘数据之间的耦合点和关联性。但图结构的扁平化特征会导致基于作战主题的深度信息搜索效率偏低。针对这一缺点,提出基于刻面思想,利用已构建军事信息知识图谱上的数据生成信息目录的方法,提高数据资源的有效利用率。

关键词：数据目录知识图谱数据挖掘刻面分类

过渡金属硫化物WS_(2)气敏性能及敏感机理研究

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大连民族大学学报 2024年第1期26卷 36-42页

作者：丛丽颖李清宇杜海英王敬张钊睿大连民族大学机电工程学院辽宁大连116650 大连理工大学机械工程学院辽宁大连116024

采用焙烧分解法合成了过渡金属硫化物WS_(2),对其形貌、结构和成分进行了表征分析,制备了WS_(2)气体传感器,研究了其对环境污染气体NO_(2)及多种干扰气体的气敏性能。实验结果显示,相较于其他干扰气体,WS_(2)气体传感器对NO_(2)的响应... 详细信息

采用焙烧分解法合成了过渡金属硫化物WS_(2),对其形貌、结构和成分进行了表征分析,制备了WS_(2)气体传感器,研究了其对环境污染气体NO_(2)及多种干扰气体的气敏性能。实验结果显示,相较于其他干扰气体,WS_(2)气体传感器对NO_(2)的响应灵敏度最高,具有良好的长期稳定性和气体选择性。基于密度泛函理论计算了WS_(2)分子对NO_(2)及其干扰气体的吸附能、电荷差分、态密度等微观电子特性,分析了过渡金属硫化物WS_(2)对NO_(2)的吸附机理。基于密度泛函理论的机理分析与实验结果相一致。

关键词：过渡金属硫化物气敏性能密度泛函理论敏感机理

CycleGAN、ACGAN在人工智能医疗器械数据增广中的应用

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中国医疗设备 2024年第2期39卷 52-56,69页

作者：郝鹏飞李瑶柴蕊裴晓娟于哲李庆雨陈曦张克山东省医疗器械和药品包装检验研究院医用电器质量评价中心山东济南250101 道普信息技术有限公司山东济南250101

目的探究人工智能医疗器械领域中使用循环生成对抗网络(Cycle-Consistent Generative Adversarial Networks,CycleGAN)和辅助分类生成对抗网络(Auxiliary Classification Generative Adversarial Network,ACGAN)进行数据增广的方法。方法使用CycleGAN和ACGAN分别生成干扰图像和特定领域数据,对图像增加不规律的变换,对原始图像数据进行数据加工或应用生成对抗网络生成该领域所需的图像数据。结果在医学影像数据集上评估了本文提出方法的性能,结果表明,CycleGAN和ACGAN可有效生成逼真的医学影像,从而用于训练机器学习模型。结论该方法解决了人工智能领域图像数据不足的问题,保证了模型对该数据的不可见性,使后期模型评估结果更准确。

关键词：循环生成对抗网络辅助分类生成对抗网络数据增广医学影像机器学习