检索结果-南通市图书馆

相位环形统计矢量对提高全聚焦成像质量的影响

在线全文

学校读者我要写书评

暂无评论

声学学报 2020年第6期45卷 913-921页

作者：冒秋琴陈尧张柏源石文泽卢超李秋锋南昌航空大学无损检测技术教育部重点实验室南昌330063 中国科学院声学研究所声场声信息国家重点实验室北京100190 赣南师范大学赣州341000

为进一步提高超声全聚焦的成像质量,提出一种基于相位环形统计矢量的全聚焦成像方法。首先,在全聚焦实施过程中提取全矩阵数据中信号的相位信息。然后,将同一聚焦像素点的相位视作环形分布的统计样本,通过饱和状态加权统计构建由幅值和... 详细信息

为进一步提高超声全聚焦的成像质量,提出一种基于相位环形统计矢量的全聚焦成像方法。首先,在全聚焦实施过程中提取全矩阵数据中信号的相位信息。然后,将同一聚焦像素点的相位视作环形分布的统计样本,通过饱和状态加权统计构建由幅值和相位分布共同决定的相位环形统计矢量。最后,将相位环形统计矢量的模等效为全聚焦图像的幅值。结果表明,该成像算法既能够通过放大相位分布对信号幅值的贡献提高信噪比,又能够通过减小声束宽度有效提高横向分辨率。相比于相位相干加权算法SCF和CCF,基于相位环形统计矢量的算法对相位偏差的容忍度更高。

关键词：加权算法加权统计横向分辨率相位偏差相位分布统计样本容忍度成像算法

Boosting the performance of liNi_(0.90)Co_(0.06)Mn_(0.04)O_(2) electrode by uniform li_(3)PO_(4) coating via atomic layer deposition

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2024年第5期35卷 499-503页

作者： Mingjiao Lu Zhixing Wang Gui Luo Huajun Guo Xinhai li Guochun Yan Qihou li Xianglin li Ding Wang Jiexi Wang School of Metallurgy and Environment Central South UniversityChangsha 410083China BASF ShanShan Battery Materials Co. Ltd.Changsha 410006China Engineering Research Center of the Ministry of Education for Advanced Battery Materials Central South UniversityChangsha 410083China Hunan Provincial Key Laboratory of Nonferrous Value-Added Metallurgy Central South UniversityChangsha 410083China School of Physics and Chemistry Hunan First Normal UniversityChangsha 410205China National and Local Joint Engineering Laboratory for lithium-ion Batteries and Materials Preparation Technology Key Laboratory of Advanced Battery Materials of Yunnan ProvinceFaculty of Metallurgical and Energy EngineeringKunming University of Science and TechnologyKunming 650093China

Ultra-high nickel material is considered to be a promising cathode ***,with the increase of nickel content,the interfacial side reactions between the cathode and electrolyte become increasingly ***,an atomically controllable ionic conductor li_(3)PO_(4)(LPO)coating is deposited on the liNi_(0.90)Co_(0.06)Mn_(0.04)O_(2)(NCM9064)based electrode by the atomic layer deposition *** results shows that the LPO coating is uniformly and densely covered on the surface of secondary particles of NCM9064,helping to prevent the direct contact between the electrolyte and cathode during the chargingdischarging *** addition,the coating layer is electrochemically *** a result,the interfacial side reactions during the long cycle are effectively suppressed,and the solid electrolyte interphase layer at the interface is *** electrode with 20 layers of LPO deposition(ALD-LPO-20)exhibits an excellent capacity retention of 81%after 200 cycles in 2.8-4.3 V at 25℃,which is 18%higher than the unmodified material(ALD-LPO-0).Besides,the moderate LPO coating improves the rate capability and high temperature cycling performance of *** study provides a method for the modification of ultra-high nickel cathode materials and corresponding electrodes.

关键词： Ultra-high nickel material liNi_(0.90)Co_(0.06)Mn_(0.04)O_(2) Atomic layer deposition li_(3)PO_(4) Ionic conductor

Layered niobium carbide enabling excellent kinetics and cycling stability of li-Mg-B-H hydrogen storage material Layered niobium carbide enabling excellent kinetics

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2024年第3期43卷 1153-1166页

作者： li-Wen Lu Hui Luo Guang-Xu li Yun li Xin-Hua Wang Cun-Ke Huang Zhi-QiangLan Wen-Zheng Zhou Jin Guo Mohammad Ismail Hai-Zhen liu Guangxi Novel Battery Materials Research Center of Engineering Technology Guangxi Colleges and Universities Key Laboratory of Blue Energy and Systems IntegrationSchool of Physical Science and TechnologyGuangxi UniversityNanning530004China State Key Laboratory of Featured Metal Materials and life-Cycle Safety for Composite Structures Nanning530004China School of Mechanical and Electrical Engineering Quzhou College of TechnologyQuzhou324000China Department of Materials Science and Engineering Zhejiang UniversityHangzhou310027China Faculty of Ocean Engineering Technology and Informatics Universiti Malaysia Terengganu21030Kuala NerusTerengganuMalaysia Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai UniversityTianjin300071China

The li-Mg-B-H composite(2liBH_(4)+MgH_(2))has a high capacity of 11.4 wt%as a hydrogen storage ***,the slow kinetics and poor cycling stability severely restrict its practical *** this work,a layered Nb_(2)C MXene was first synthesized and then introduced to tailor the kinetics and cycling stability of the li-Mg-B-H *** milled 2liH+MgB_(2)composites were initially hydrogenated to obtain the 2liBH_(4)+MgH_(2)*** 2liBH_(4)+MgH_(2)+5wt%Nb_(2)C can release 9.0 wt%H_(2)in 30 min at 400℃,while it is only 2.7 wt%for the undoped 2liBH_(4)+MgH_(2).The dehydrogenation activation energies of MgH_(2)and liBH_(4)are 123 and 154 kJ·mol^(-1)respectively for the 5 wt%Nb_(2)C-doped composite,lower than the undoped composite(164 and 165 kJ·mol^(-1)).The 2liBH_(4)+MgH_(2)+5 wt%Nb_(2)C possesses excellent cycling stability,with the reversible capacity only slightly reduced from 9.4 wt%for the 1st cycle to 9.3 wt%for the 20th ***_(2)C keeps stable in the composite and acts as an efficient catalyst for the li-Mg-B-H *** is believed that both the layered structure and the active Nb element contribu te to the enhanced hydrogen storage performances of the li-Mg-B-H *** work confirms that the Nb_(2)C MXene with layered stru cture has a significant enhancing impact on the li-Mg-B-H hydrogen storage materials,which is different from the bulk NbC.

关键词： Hydrogen storage lithium borohydride Magnesium hydride Nb_(2)C MXene

Hard-carbon hybrid li-ion/metal anode enabled by preferred mesoporous uniform lithium growth mechanism

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2024年第1期88卷 252-259,I0006页

作者： Fang Yan Yan liu Yuan li Yan Wang Zicen Deng Meng li Zhenwei Zhu Aohan Zhou Ting li Jingyi Qiu Gaoping Cao Shaobo Huang Biyan Wang Hao Zhang School of Chemistry and Biological Engineering University of Science and TechnologyBeijing 100083China Research Institute of Chemical Defense Beijing 100191China College of Physics and Engineering Henan University of Science and TechnologyLuoyang 471023HenanChina National Base for International Science&Technology Cooperation School of ChemistryXiangtan UniversityXiangtan 411105HunanChina Materials and Manufacturing Department Beijing University of TechnologyBeijing 100124China

To achieve high energy density in lithium batteries,the construction of lithium-ion/metal hybrid anodes is a promising *** particular,because of the anisotropy of graphite,hybrid anode formed by graphite/li metal has low transport kinetics and is easy to causes the growth of lithium dendrites and accumulation of dead li,which seriously affects the cycle life of batteries and even causes safety ***,by comparing graphite with two types of hard carbon,it was found that hybrid anode formed by hard carbon and lithium metal,possessing more disordered mesoporous structure and lithophilic groups,presents better *** indicate that the mesoporous structure provides abundant active site and storage space for dead *** the synergistic effect of this structure and lithophilic functional groups(–COOH),the reversibility of hard carbon/lithium metal hybrid anode is maintained,promoting uniform deposition of lithium metal and alleviating formation of lithium *** hybrid anode maintains a 99.5%Coulombic efficiency(CE)after 260 cycles at a specific capacity of 500 m Ah/*** work provides new insights into the hybrid anodes formed by carbon-based materials and lithium metal with high specific energy and fast charging ability.

关键词： Hard carbon/li metal hybrid anode Mesoporous structure Surface oxygen functional group Fast charging lithium batteries

在线全文

学校读者我要写书评

暂无评论

自动气电立焊摆动系统设计及其控制研究

江苏科技大学学报（自然科学版） 2010年第5期24卷 457-460页

作者：李钦奉尹美富崔海安江苏科技大学机械工程学院江苏镇江212003 江苏科技大学先进焊接技术省重点实验室江苏镇江212003

针对船体厚板立缝焊接工艺中焊枪摆动难于控制,枪头、导电嘴容易与壁板短路接触引弧形成虚假熔池从而导致焊接质量下降等问题,对自动气电立焊的摆动系统进行机械传动设计和电路控制.设计了锥齿轮传动、行星轮传动蜗轮蜗杆传动和行程开... 详细信息

针对船体厚板立缝焊接工艺中焊枪摆动难于控制,枪头、导电嘴容易与壁板短路接触引弧形成虚假熔池从而导致焊接质量下降等问题,对自动气电立焊的摆动系统进行机械传动设计和电路控制.设计了锥齿轮传动、行星轮传动蜗轮蜗杆传动和行程开关组合摆动机构;基于JK触发器和组合逻辑门电路设计了电机正反控制电路和时滞电路.经焊接试验证明此摆动系统能获得板厚方向等熔深的良好效果.

关键词：气电立焊摆动设计摆动控制

在线全文

学校读者我要写书评

暂无评论

基于软翅振动稀相气固两相流动特性分析

江苏科技大学学报（自然科学版） 2017年第4期31卷 468-472页

作者：李钦奉朱雷晏飞杜雨辰江苏科技大学机械工程学院镇江212003

针对安装软翅模型的水平管气力输送气固两相流流动特性进行了数值分析.以软翅振动频率为主要变量,通过Fluent-Profile功能编写自激振荡流程序进行二次开发,并利用离散相模型(DPM)对气相速度矢量图、物料入口的颗粒路径、加速区颗粒速度... 详细信息

针对安装软翅模型的水平管气力输送气固两相流流动特性进行了数值分析.以软翅振动频率为主要变量,通过Fluent-Profile功能编写自激振荡流程序进行二次开发,并利用离散相模型(DPM)对气相速度矢量图、物料入口的颗粒路径、加速区颗粒速度矢量及稳定区的颗粒浓度分布进行定性分析.结果表明:安装软翅模型时,在软翅模型附近位置产生涡流,改变了气相流动方向,使加速区粒子得到了悬浮和加速.

关键词：气力输送粒子路径粒子浓度粒子速度

Catalytic anode surface enabling in situ polymerization of gel polymer electrolyte for stable li metal batteries

在线全文

学校读者我要写书评

暂无评论

Nano Research 2024年第6期17卷 5216-5223页

作者： Guocheng li Kang liang Yuanjian li Xiangrui Duan lin Fu Zhao Cai Zhaofu Zhang Jiangnan Dai Yongming Sun Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074China The Institute of Technological Sciences Wuhan UniversityWuhan 430074China Faculty of Materials Science and Chemistry China University of Geoscience(Wuhan)Wuhan 430074China

Employing quasi-solid-state gel polymer electrolyte(GPE)instead of the liquid counterpart has been regarded as a promising strategy for improving the electrochemical performance of li metal ***,the poor and uneven interfacial contact between li metal anode and GPE could cause large interfacial resistance and electrochemical li stripping/plating inhomogeneity,deteriorating the electrochemical ***,we proposed that the functional component of composite anode could work as the catalyst to promote the in situ polymerization reaction,and we experimentally realized the integration of polymerized-dioxolane electrolyte and li/li_(22)Sn_(5)/liF composite electrode with low interfacial resistance and good stability by in situ catalyzation ***,the reaction kinetics and stability of metallic li anode were significantly *** a demonstration,symmetric cell using such a GPE-li/li_(22)Sn_(5)/liF integration achieved stable cycling beyond 250 cycles with small potential hysteresis of 25 mV at 1 mA·cm^(−2)and 1 mAh·cm^(−2),far outperforming the counterpart regular GPE on pure *** with liNi0.5Co0.3Mn0.2O2,the full cell with the GPE-li/li_(22)Sn_(5)/liF integration maintained 85.7%of the original capacity after 100 cycles at 0.5 C(1 C=200 mA·g^(−1)).Our research provides a promising strategy for reducing the resistance between GPE and li metal anode,and realizes li metal batteries with enhance electrochemical performance.

关键词： catalyzation polymerization interface resistance interfacial stability li metal batteries electrochemical performance

Enhanced electrochemical performance of li_(1.3)Al_(0.3)Ti_(1.7)(PO_(4))_(3) solid electrolyte by anion doping

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

Nano Research 2024年第3期17卷 1465-1472页

作者： Jingrui Kang Xu Guo Rui Gu Honglei Hao Yi Tang Jiahui Wang li Jin Hongfei li Xiaoyong Wei Electronic Materials Research Laboratory Key Laboratory of the Ministry of Education&International Center for Dielectric ResearchSchool of Electronic and Information EngineeringXi’an Jiaotong UniversityXi’an 710049China School of Energy and Materials Shanghai Key Laboratory of Engineering Materials Application and EvaluationShanghai Polytechnic UniversityShanghai 201209China

Nowadays,the majority of the studies on the substitution are focused on cations(such as Y^(3+),Ti^(4+),P^(5+),etc.)in li_(1.3)Al_(0.3)Ti_(1.7)(PO_(4))_(3)(LATP),while there are few studies on the substitution of anion O^(2-).In this work,the modified LATP with a series of liCl(LATPClx,x=0.1,0.2,0.3,0.4)additives is prepared to enhance ionic *** successful introduction of Cl-makes the length of the c axis decrease from 20.822(2)to 20.792(1)Å,and the bulk conductivity of 2.13×10^(-3) S·cm^(-1) is achieved in LATPCl_(0.3).Moreover,the Al/Ti-O1/Cl1 and Al/Ti-O_(2)/Cl_(2) distance decrease,while the li1-O_(2)/Cl_(2) distance *** ions migrate more easily in the nanochannel of *** addition,the liCl additive increases the relative density and the grain boundary conductivity of LATPClx ***,a higher ionic conductivity of 2.12×10^(–4) S·cm^(-1) and a low activation energy of 0.30 eV are obtained in LATPCl_(0.3).Correspondingly,the symmetric cell exhibits a low overpotential of±50 mV for over 200 h in LATPCl_(0.3).The solid-state li|LATPCl_(0.3)|NCM811(NCM811=liNi0.8Co0.1Mn0.1O_(2))battery exhibits high initial capacity 185.1 mAh·g^(-1) with a capacity retention rate of 95.4%after 100 cycles at 0.5 *** result suggests that liCl additive is an effective strategy to promote electrochemical properties of LATP solid electrolyte and can be considered for reference to other inorganic solid electrolytes systems.

关键词： li_(1.3)Al_(0.3)Ti_(1.7)(PO_(4))_(3)(LATP)solid electrolyte anion doping ionic conductivity cyclic performance

Vinyltrimethylsilane as a novel electrolyte additive for improving interfacial stability of li-rich cathode working in high voltage

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

Chinese Chemical Letters 2024年第2期35卷 534-538页

作者： Bing Jiang Hao li Bi Luo Lehao liu lihua Chu Qiaobao Zhang Meicheng li State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources School of New EnergyNorth China Electric Power UniversityBeijing 102206China State Key Laboratory of Physical Chemistry of Solid Surfaces College of MaterialsXiamen UniversityXiamen 361005China

Boosting the interfacial stability between electrolyte and li-rich cathode material at high operating voltage is vital important to enhance the cycling stability of li-rich cathode materials for high-performance li-ion *** this work,vinyltrimethylsilane as a new type of organic silicon electrolyte additive is studied to address the interfacial instability of li-rich cathode material at high operating *** cells using vinyltrimethylsilane additive shows the high capacity retention of 73.9%after 300 cycles at 1 C,whereas the cells without this kind of additive only have the capacity retention of 58.9%.The improvement of stability is mainly attributed to the additive helping to form a more stable surface film for li-rich cathode material,thus avoiding direct contact between the electrolyte and the cathode material,slowing down the dissolution of metal ions and the decomposition of the electrolyte under high operating *** findings in this work shed some light on the design of stable cycling performance of li-rich cathode toward advanced li-ion batteries.

关键词： Vinyltrimethylsilane Electrolyte additive li-rich cathode Interfacial stability Capacity retention