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Improved electrochemical performances of yttrium oxyfluoride-coated Li[Li0.2Mn0.54Ni0.13Co0.13]O2 for lithium ion batteries

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Journal of Energy Chemistry 2018年第4期27卷 1239-1246页

作者： Yaxin Hao Fangning Yang Didi Luo jianhua tian Zhongqiang Shan School of Chemical Engineering and Technology Tianjin UniversityTianjin 300350.China The 18th Research Institute of China Electronics Technology Group Corporation Tianjin 300384.China

The Li-rich layered oxides show a higher discharge capacity over 250 mAh/g and have been developed into a promising positive material for lithium ion batteries. A rare earth metal oxyfluoride YOF-coated Li[Lio.2Mno.54Ni0.13Co0.13]O2 composites have been synthesized by a simple wet chem- ical method. Crystal structure, micro-morphology and element valence of the pristine and YOF-coated Li[Li0.2Mn0.54Ni0.13Co0.13]O2 materials are characterized by XRD, SEM, TEM, and XPS. The results indicate that all materials exhibit a typical layered structure, and are made up of small and homogenous parti- cles ranging from 100 nm to 200 nm. In addition, YOF layer with a thickness of approximately 3-8 nm is precisely coated on the surface of the Li[Li0.2Mn0.54Ni0.13Co0.13]02. Constant current charge/discharge tests at various current densities show that the electrochemical performance of 2 wt% YOF-coated Li[Li0.2Mn0.54Ni0.13Co0.13]O2 has been improved significantly. 2 wt% YOF-coated Li[Li0.2Mn0.54Ni0.13Co0.13]O2 delivers the highest discharge capacity of 250.4 mAh/g at 20 mA/g among all the samples, and capacity retention of 87% after 100 charge/discharge cycles at 200 mA/g while that of the pristine one is only 81.6%. The superior electrochemical performance of 2wt% YOF-coated sample is ascribed to YOF coating layer, which could not only reduce side reactions between the electrode and liquid electrolyte, but also promote lithium ion migration.

关键词： Li[Li0.2 Mn0.54 Ni0.13 Co0.13]O2 YOF-coated Cathode material Lithium ion battery

Enhancing the resolution of seismic data based on the generalized S-transform

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Petroleum Science 2009年第2期6卷 153-157页

作者： tian jianhua Song Wei Yang Feizhou State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum Beijing 102249 China Key Laboratory of CNPC Geophysical Prospecting China University of Petroleum Beijing 102249 China

In this paper, we analyze the seismic signal in the time-frequency domain using the generalized S-transform combined with spectrum modeling. Without assuming that the reflection coefficients are random white noise as in the conventional resolution-enhanced techniques, the wavelet which changes with time and frequency was simulated and eliminated. After using the inverse S-transform for the processed instantaneous spectrum, the signal in the time domain was obtained again with a more balanced spectrum and broader frequency band. The quality of seismic data was improved without additional noise.

关键词： Time-frequency domain generalized S-transform spectrum modeling instantaneous spectrum balanced spectrum

综合智能化医院物流系统在大型医院的综合运用

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绿色建造与智能建筑 2025年第1期 146-150页

作者：田建华中铁建设集团南方工程有限公司广州511466

本文介绍了箱式物流、气动物流、垃圾被服收集物流、物流机器人的基本结构和工作逻辑,四者有机结合后,为大型医院智能化物流传输系统的工作可靠性及覆盖率提供了保障。并以佛山某医院为例介绍了该套综合物流传输系统的运营模式。

关键词：箱式物流气动物流垃圾被服动力物流覆盖率

Recent advances in metal-loaded MOFs photocatalysts:From single atom,cluster to nanoparticle

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Chinese Chemical Letters 2025年第1期36卷 68-79页

作者： Shenglan Zhou Haijian Li Hongyi Gao Ang Li tian Li Shanshan Cheng Jingjing Wang Jitti Kasemchainan jianhua Yi Fengqi Zhao Wengang Qu Advanced Innovation Center for Materials Genome Engineering Beijing Key Laboratory of Function Materials for Molecule&Structure ConstructionSchool of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijing 100083China National Key Laboratory of Energetic Materials Xi’an Modern Chemistry Research InstituteXi’an 710065China Shunde Innovation School University of Science and Technology BeijingShunde 528399China School of Materials Science and Engineering Suzhou University of Science and TechnologySuzhou 215009China Department of Chemical Technology Chulalongkorn UniversityBangkok 10330Thailand

Photocatalysis is widely regarded as a highly promising sustainable technique for addressing the challenges posed by environmental pollution and energy *** recent years,metal-loaded MOFs has become a rising star within the domain of photocatalysis due to its high specific surface area and porosity,adjustable structure,diverse and abundant catalytic components,which has exhibited excellent photocatalytic activity and exhibit great potential in a range of *** this paper,the principles for evaluating the photocatalytic performance of MOFs-based materials were firstly introduced,and some typical examples were also listed *** with this,particular emphasis is paid to the main factors affecting the photocatalytic performance of metal-loaded *** the synthesis and design strategies of MOFs loaded metal entities of varying sizes(single atoms,nanoclusters,and nanoparticles),and their applications in photocatalytic CO_(2)reduction,hydrogen production,photooxidation and photocatalytic hydrogenation were summarized and ***,the opportunities and challenges faced in this kind of MOFs-based composites were analyzed from different *** report is expected to help researchers design and develop high-performance MOFs-based photocatalytic materials.

关键词： Metal-loaded MOFs Photocatalysis Single atom catalysts Nanoclusters Nanoparticles

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深部储层流体识别方法在仁和场地区的应用

地球物理学进展 2022年第2期37卷 656-663页

作者：田建华中国石油化工股份有限公司石油物探技术研究院南京211103

仁和场地区位于米仓山构造带前缘,该区下组合成藏条件优越,但目的层埋藏深度超过8000 m.深部地震资料通常缺少大炮检距信息并且信噪比低,这给叠前地震反演和流体识别带来了巨大挑战.针对这一问题,本研究采用基于基追踪弹性阻抗反演的两... 详细信息

仁和场地区位于米仓山构造带前缘,该区下组合成藏条件优越,但目的层埋藏深度超过8000 m.深部地震资料通常缺少大炮检距信息并且信噪比低,这给叠前地震反演和流体识别带来了巨大挑战.针对这一问题,本研究采用基于基追踪弹性阻抗反演的两项式深部储层流体识别方法,对仁和场地区进行流体识别的应用研究.研究表明:(1)基于模型约束的基追踪反演方法提高了反演的抗噪性,两项式的反演结果和常规三项式相比与测井和地质认识吻合度更高,说明该方法具有一定的实用性;(2)在利用岩石物理模型预测横波速度时考虑围压修正关系对模型进行优化,减小深层压力对预测精度的影响,有利于提高流体的识别精度;(3)反演流体项的计算中涉及到较多的岩石物理参数,因此针对实际工区开展一定的岩石物理实验是提高深部储层流体识别精度的关键环节.

关键词：深部储层两项弹性阻抗方程基追踪反演仁和场流体识别

MODE SPACE SMOOTHING ALGORITHM TO ESTIMATE DOA OF COHERENT SIGNALS IMPINGING ON UNIFORM CIRCULAR ARRAY

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Journal of Electronics(China) 1998年第4期15卷 289-295页

作者： Ma Changlin Peng Yingning tian Lisheng Liu jianhua(Department of Electronic Engineering, Tsinghua University, Beijing 100084) Department of Electronic Engineering Tsinghua University Beijing

A novel method to estimate DOA of coherent signals impinging on a uniform circular array( UCA) is presented in this paper. A virtual uniform linear array (VULA) is first derived by using spatial DFT technique, transforming the UCA from element space to phase mode space to obtain the properties of ordinary ULA, and then the well known spatial smoothing technique is applied to the VULA so that the lost rank of covariance matrix due to signal coherence can be retrieved. This method makes it feasible to use the simple MUSIC algorithm to estimate DOA of coherent signals impinging on a UCA without heavy computation burden. Simulation results strongly verify the effectiveness of the algorithm.

关键词： Mode space Virtual uniform linear array Spatial smoothing

Fe的掺杂对LiMnPO4材料电化学性能的影响

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高技术通讯 2012年第10期22卷 1103-1108页

作者：曾福娣单忠强田建华天津大学应用化学系天津300072

采用高温固相法合成了Fe掺杂（掺杂的质量分数分别为0，0．05，0．1，0．15，0．2）的LiMnPO4材料，利用X射线衍射（XRD）分析、透射电镜（TEM）对材料进行了物相和形貌表征，利用充放电测试和循环伏安测量方法研究了材料的电化学性能... 详细信息

采用高温固相法合成了Fe掺杂（掺杂的质量分数分别为0，0．05，0．1，0．15，0．2）的LiMnPO4材料，利用X射线衍射（XRD）分析、透射电镜（TEM）对材料进行了物相和形貌表征，利用充放电测试和循环伏安测量方法研究了材料的电化学性能。结果表明，掺杂后的材料电化学性能远优于未掺杂材料。各掺杂材料36次循环之后有较高的容量保持率；0．1C充放电时掺杂量为0．05的材料首次放电比容量最大，达到155．5mAh／g，且其各倍率下的电化学性能都优于其它掺杂材料。用循环伏安法计算出了Li＋的扩散系数，结果显示．掺杂后的材料具有相对较大的扩散系数。

关键词：锂离子电池磷酸锰锂固溶体电化学性能扩散系数