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Understanding and modifications on lithium deposition in lithium metal batteries

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Rare Metals 2022年第8期41卷 2800-2818页

作者： Qin-ya yang Zhao Yu yao Li Wang Zhang Hao-Wen Yuan Hong-Jie Li Wei Ma Shen-Min Zhu sa Li State Key Laboratory of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai200240China School of Materials Science and Engineering Tongji UniversityShanghai201804China

Lithium metal has been considered as an ultimate anode choice for next-generation secondary batteries due to its low density,superhigh theoretical specific capacity and the lowest voltage ***,uncontrollable dendrite growth and consequently large volume change during stripping/plating cycles can cause unsatisfied operation efficiency and serious safety concern,restraining its commercial use for the last 40 *** widely used lithium-ion battery is approaching its theoretical limit at present,it is increasingly urgent to develop new energy storage equipment with sufficient practical ***,two important processes of lithium deposition,nucleation and growth on lithium metal anode are *** three-dimensional(3 D)porous anodes with unique structure and dynamic surface conditions,as one of the most efficient designs on dendrites suppression,are specifically discussed in terms of their beneficial adjustment on the dendrite *** on current designs and prospects on future advanced porous anode are explored in the end.

关键词： Lithium metal batteries Lithium nucleation Dendrites growth Porous anodes

Synthesis and applications of low dielectric polyimide

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Resources Chemicals and Materials 2023年第1期2卷 49-62页

作者： Yu Liu Xiao-Yu Zhao ya-Guang Sun Wen-Ze Li Xiao-sa Zhang Jian Luan College of Science Shenyang University of Chemical TechnologyShenyang110142P R China College of Sciences Northeastern UniversityShenyang100819P R China

With the advent of the 5 G era,advanced packaging applications such as wafer-level fan-out packaging have emerged thanks to efforts to reduce signal loss and increase signal transmission *** one of the key materials employed in telecommunication devices,the interlayer dielectric material directly affects signal transmission and device *** them,polyimide(PI)has become an important interlayer dielectric material because of its excellent comprehensive ***,in order to meet the needs high-frequency and high-speed circuits for 5 G networks,it will be necessary to further reduce the dielectric constant and dielectric loss of *** is widely used as a flexible dielectric material due to its excellent electrical insulation properties(dielectric constant≈3.0-4.0,dielectric loss≈0.02),mechanical properties,and thermal ***,further reduction in the dielectric constant will be needed in order for PI-based materials to better meet the current high integration development needs of the microelectronics *** article starts from strategies to prepare low dielectric PI that have been developed in the last decade,based on a more systematic and inductive analysis,and prospects the development potential of low dielectric PI.

关键词： Polyimide Low dielectric constant Nanocomposite materials Polyimide films

The application of conceptual fluency to English teaching

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Sino-US English Teaching 2009年第11期6卷 31-35页

作者： sa Zhong-qing WANG ya-li School of Foreign Languages Jiangnan University Jiangsu 214122 China School of Foreign Studies Nanjiang Xiaozhuang Normal College Nanjing 210045 China

The term of ＂conceptual fluency＂ put forward by Danesi offers a fresh perspective to look at the current disturbing situation that confronts college English teaching in China. This paper propounds its theoretical basis by reflecting on the philosophical and linguistic trends in modern era, and points out the defects of Danesi＇s theory, insisting that conceptual fluency should be built on both the lexical and grammatical levels. It then exemplifies the implementation of the theory in actual teaching practice.

关键词： conceptual fluency conceptual metaphor cognitive linguistics English teaching

Ultra-lightweight CNN design based on neural architecture search and knowledge distillation: A novel method to build the automatic recognition model of space target IsaR images

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Defence Technology（防务技术） 2022年第6期18卷 1073-1095页

作者： Hong yang ya-sheng Zhang Can-bin Yin Wen-zhe Ding Space Engineering University Beijing101416China Beijing Institute of Tracking and Telecommunications Technology China

In this paper,a novel method of ultra-lightweight convolution neural network(CNN)design based on neural architecture search(NAS)and knowledge distillation(KD)is *** can realize the automatic construction of the space target inverse synthetic aperture radar(IsaR)image recognition model with ultra-lightweight and high *** method introduces the NAS method into the radar image recognition for the first time,which solves the time-consuming and labor-consuming problems in the artificial design of the space target IsaR image automatic recognition model(STIIARM).On this basis,the NAS model’s knowledge is transferred to the student model with lower computational complexity by the flow of the solution procedure(FSP)distillation ***,the decline of recognition accuracy caused by the direct compression of model structural parameters can be effectively avoided,and the ultralightweight STIIARM can be *** the method,the Inverted Linear Bottleneck(ILB)and Inverted Residual Block(IRB)are firstly taken as each block’s basic structure in *** the expansion ratio,output filter size,number of IRBs,and convolution kernel size are set as the search parameters to construct a hierarchical decomposition search ***,the recognition accuracy and computational complexity are taken as the objective function and constraint conditions,respectively,and the global optimization model of the CNN architecture search is ***,the simulated annealing(sa.a.gorithm is used as the search strategy to search out the lightweight and high accuracy STIIARM *** that,based on the three principles of similar block structure,the same corresponding channel number,and the minimum computational complexity,the more lightweight student model is designed,and the FSP matrix pairing between the NAS model and student model is ***,by minimizing the loss between the FSP matrix pairs of the NAS model and student model,the student model’s weight adjust

关键词： Space target IsaR image Neural architecture search Knowledge distillation Lightweight model

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西藏岩画中的“鸟图形”

西藏研究 2006年第2期 50-60页

作者：张亚莎中央民族大学岩画中心北京100081

西藏岩画中数量丰富的“鸟图形”,显示出“鸟(鹰)”在西藏早期文化中的特殊地位,后期相当部分的“鸟图形”岩画,看上去颇有些超自然的意味,但早期岩画中的鸟图形可能仍是高原自然生态环境的一种表现,只是随着苯教文化的发展,逐渐赋予了... 详细信息

西藏岩画中数量丰富的“鸟图形”,显示出“鸟(鹰)”在西藏早期文化中的特殊地位,后期相当部分的“鸟图形”岩画,看上去颇有些超自然的意味,但早期岩画中的鸟图形可能仍是高原自然生态环境的一种表现,只是随着苯教文化的发展,逐渐赋予了鸟图形以特殊的意义。据苯教文献记载,古代象雄部落是神鸟“(?)”(穹)的后裔,西藏岩画中这些带有神秘意义的“鸟图形”,显然与古代象雄部族的神鸟“穹”的崇拜习俗有直接关系。西藏岩画中丰富多彩的“鸟巫”形象也向我们证实:古代象雄苯教巫师在做法事时,力图将自己打扮成鸟形,不仅用以显示巫师不同寻常的魔力,更重要的是与神鸟“穹”保持精神上的一致,“鸟巫”正是古代象雄部族“鸟图腾”文化的一种延伸。西藏岩画以其极为生动丰富的图像,成为古代象雄文化发展过程的形象注解,在古代象雄文化缺乏考古实物的今天,它们无疑将是我们解读神秘的古代象雄文化的一个重要途径。

关键词：西藏岩画鸟图形神鸟穹鸟图腾鸟冠鸟巫古代象雄

Rationalizing the impact of oxygen vacancy on polysulfide conversion kinetics for highly efficient lithium-sulfur batteries

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Journal of Energy Chemistry 2023年第12期87卷 51-60,I0003页

作者： ya Song Huan Li Junfeng Li Jinyu An Jiao-Jing Shao Guangmin Zhou School of Materials and Metallurgy Guizhou UniversityGuiyang 550025GuizhouChina School of Chemical Engineering and Advanced Materials The University of AdelaideAdelaideSA 5005Australia Shenzhen Geim Graphene Center Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055GuangdongChina College of Civil Engineering Guizhou UniversityGuiyang 550025GuizhouChina

The“shuttle effect”of lithium polysulfides(LiPSs)is a huge challenge for practical use of high-energydensity lithium-sulfur(Li-S)batteries,and one of the main reasons is the sluggish kinetics of sulfur *** oxides are able to expedite the sulfur electrochemistry,and the structural defects enhance the adsorption-conversion ability of metal oxides for ***,a significant research gap still remains regarding the relationship between the oxygen vacancy concentration and the adsorptivecatalytic performance of metal ***,we establish a correlation between oxygen vacancy concentration and adsorptive-catalytic properties by using tungsten oxide(WO_(x))as model *** is revealed that high-concentration oxygen vacancy is beneficial for enhancing the binding between tungsten oxide and LiPSs,reducing the energy barrier of Li_(2)S decomposition,and promoting polysulfide conversion ***,the Li-S batteries using the tungsten oxide with high-concentration oxygen vacancies deliver high initial discharge capacity of 1169 mA h g^(-1)at 0.2 C and 865 mA h g^(-1)at 2 C,low attenuation rate of 0.064%per cycle over 1100 cycles at 2 *** a high sulfur area loading of 5.34 mg cm^(-2),the Li-S batteries still exhibit high initial gravimetric capacity of 982 mA h g^(-1)at 0.1 C and areal capacity of 5.92 mA h cm^(-2).This work promotes the feasibility of defect engineering on metal oxides as an effective mean to enhance the practicality of Li-S batteries.

关键词： Shuttl eeffect Oxygen vacancy Interlayer Lithium-sulfur batteries

Hexagonal MBenes-Supported Single Atom as Electrocatalysts for the Nitrogen Reduction Reaction

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Energy Material Advances 2023年第1期4卷 331-343页

作者： ya Gao Erpeng Wang yazhuo Zheng Jian Zhou Zhimei Sun School of Materials Science and Engineering Beihang UniversityBeijing 100191China

The electrocatalytic nitrogen reduction reaction(NRR)is currently constrained by sluggish reaction kinetics and poor selectivity because of the difficulties in activating inert N≡N triple bonds and the existence of competing hydrogen evolution reaction(HER).Therefore,electrocatalysts with high activity,selectivity,and stability are highly ***,by means of first-principles calculations,we investigated the electrocatalytic NRR performance of a series of transition metal atoms(e.g.,3d,4d,and 5d)embedded in defective hexagonal MBene nanosheets[h-Zr(Hf)_(2)B_(2)O_(2)]and identified that h-Zr(Hf)_(2)B_(2)O_(2) could be an excellent platform for electrocatalytic *** the basis of our proposed screening criteria,16 candidates are efficiently selected out from 50 systems,among which,Zr_(2)B_(2)O_(2)-Cr stands out with high selectivity to NRR against HER and the ultralow limiting potential(−0.10 V).The value is much lower than that of the well-established stepped Ru(0001)surface(−0.43 V).The origin of the high activity toward NRR is attributed to the synergistic effect of the single atom(sa.a.d the M atoms in the *** impressively,a composition descriptor is further proposed on the basis of the inherent characteristics of the catalysts[number of valence electrons of sa.a.d electronegativity of the sa.a.d Zr(Hf)atoms],which helps to better predict the catalytic *** work not only contributes to the development of highly efficient NRR electrocatalysts but also extend the application of h-MBenes in electrocatalysis.

关键词： selectivity bonds kinetics

In-situ synthesis of N, S co-doped hollow carbon microspheres for efficient catalytic oxidation of organic contaminants

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Chinese Chemical Letters 2022年第3期33卷 1298-1302页

作者： Yongbing Xie ya Liu Yujie yao yanchun Shi Binran Zhao Yuxian Wang State Key Laboratory of Vanadium and Titanium Resources Comprehensive Utilization Panzhihua 617000China CAS Key Laboratory of Green Process&Engineering Beijing Engineering Research Center of Process Pollution ControlInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China State Key Laboratory of Heavy Oil Processing State Key Laboratory of Petroleum Pollution ControlChina University of Petroleum-BeijingBeijing 102249China School of Chemical Engineering and Advanced Materials The University of AdelaideAdelaideSA 5005Australia School of Chemical Engineering Northwest UniversityXi'an 710069China

Metal-free heteroatom doped nanocarbons are promising alternatives to the metal-based materials in catalytic ozonation for destruction of aqueous organic contaminants. In this study, N, S co-doped hollow carbon microspheres (NSCs) were synthesized from the polymerization products during persulfate wet air oxidation of benzothiazole. The contents of doped N and S as well as the structural stability were maneuvered by adjusting the subsequent N_(2)-annealing temperature. Compared with the prevailing single-walled carbon nanotubes, the N_(2)-annealed NSCs demonstrated a higher catalytic ozonation activity for benzimidazole degradation. According to the quantitative structure-activity relationship (QsaR) analysis, the synergistic effect between the graphitic N and the thiophene-S which redistributed the charge distribution of the carbon basal plane contributed to the activity enhancement of the N_(2)-annealed NSCs. Additionally, the hollow structure within the microspheres served as the microreactor to boost the mass transfer and reaction kinetics via the nanoconfinement effects. Quenching and electron paramagnetic resonance (EPR) tests revealed that benzimidazole degradation was dominated by the produced singlet oxygen (^(1)O_(2)) species, while hydroxyl radicals (^(·)OH) were also generated and participated. This study puts forward a novel strategy for synthesis of heteroatom-doped nanocarbons and sheds a light on the relationship between the active sites on the doped nanocarbons and the catalytic performance.

关键词： Metal-free catalysis Hollow carbon microspheres N,S co-doping Catalytic ozonation Singlet oxygen(1O_(2))

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美国残疾人体育自组织发展研究及启示

北京体育大学学报 2015年第6期38卷 6-11页

作者：吴卅黄亚玲国家体育总局体育科学研究所北京100061 北京体育大学北京100084

运用文献资料法、实地调查法、访谈法等研究方法,对美国残疾人体育组织进行了实证研究,借助"自组织"的理论视角,探讨美国残疾人体育如何依靠各要素——残疾人体育组织间的协同合作,实现了其自组织演化进程。研究认为:在各级各类残疾人... 详细信息

运用文献资料法、实地调查法、访谈法等研究方法,对美国残疾人体育组织进行了实证研究,借助"自组织"的理论视角,探讨美国残疾人体育如何依靠各要素——残疾人体育组织间的协同合作,实现了其自组织演化进程。研究认为:在各级各类残疾人体育组织的主导下,美国残疾人体育逐渐从无到有、从弱到强,并逐步获得了主流社会的认可,并通过其内在协同机制,实现了从"无序"到"有序"、从"低序"到"高序"、从"简单"到"复杂"的自组织演化。研究启示:为残疾人创造参与体育活动的社会环境、扶持和培育残疾人体育组织、加强残疾人体育与健全人体育资源融合。为我国了解国外残疾人体育发展提供了宝贵的实证素材,同时也为未来我国残疾人体育事业的发展开拓了新视野。

关键词：残疾人体育体育组织自组织组织结构体育发展模式体育资源