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A novel micro-rolling&incremental sheet forming hybrid process:Deformation behavior and microstructure evolution

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Chinese Journal of Aeronautics 2024年第5期37卷 603-622页

作者： Yanle li Feifei liU Hao YUAN Xiaoqiang li Jianfeng li Guoqun ZHAO Key Laboratory of High Efficiency and Clean Mechanical Manufacture Ministry of EducationShandong UniversityJi'nan 250061China School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Key Laboratory for liquid-Solid Structural Evolution and Processing of Materials Ministry of EducationShandong UniversityJi'nan 250061China

Thin-walled metal parts with functional micro-featured surface have broad application prospects in the fields of resistance reduction,noise reduction,*** this study,a novel micro-rolling&incremental sheet forming hybrid process(μR-ISF)is proposed to fabricate thin-walled metal parts with microgroove *** analytical model which relates the rolling force and microgroove depth in the micro-rolling stage was first ***,the formation mechanism of microgroove morphology during both micro-rolling stage and macro-shape forming stage are *** the micro-grooved sheet being incrementally formed,a significant reduction(between 21%to nearly 60%)is occurred in the depth of both transverse and longitudinal grooves compared to the flat ***,the width of transverse grooves decreases slightly by about 10%on average,while the width of longitudinal microgrooves increases significantly by more than 30%on *** micro-rolling,85°{102}tensile twins appear on the micro-grooved sheet and the percentage of 65°{112}compressive twins *** incremental forming,the percentage of low-angle grain boundaries and the density of geometrically necessary dislocations in the formed part increase significantly,and the grain size distribution becomes more *** present work provides a new strategy for the fabrication of 3D metal thin-walled components with surface micro-features.

关键词： Incremental sheet forming Microgrooves rolling Surface micromachining Groove size Microstructural evolution

Biomechanical energy harvesting technologies for wearable electronics:Theories and devices

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Friction 2024年第8期12卷 1655-1679页

作者： Xiaowen li Xu ZENG Junwei li Boyuan li Yu CHEN Xiaosheng ZHANG University of Electronic Science and Technology of China Chengdu 611731China

Wearable biomechanical energy harvesting devices have received a lot of attention recently,benefiting from the rapid advancement of theories and devices in the field of the micro electromechanical system(MEMS).They not only fulfil the requirements for powering wearable electronic devices but also provide an attractive prospect for powering self-powered flexible electronic devices when *** this article,we provide a review of the theories and devices of biomechanical energy harvesting technology for wearable *** different forms of biomechanical energy harvesting mechanisms,including the piezoelectric effect,electromagnetic effect,and electrostatic effect,are investigated in *** fundamental principle of converting other types of energy from the biomechanical environment into electrical energy,as well as the most commonly-used analytical theoretical models,are outlined for each ***,the features,properties,and applications of energy harvesting devices are *** addition,the coupled multi-effect hybrid energy harvesting devices are listed,showing the various possibilities of biomechanical energy harvesting devices for serving as sources,sensors,and ***,we present perspectives on the future trends of biomechanical energy harvesting devices for wearable electronics applications.

关键词： micro electromechanical system(MEMS) nanogenerators biomechanical energy harvesters wearable electronics

A hybrid nickel/iron-pyromellitic acid electrocatalyst for oxygen evolution reaction

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Nano Research 2024年第4期17卷 2481-2491页

作者： Guoqi li lin li Wenlong li Fusheng li Chunze Yuan Nian Zhang Hui Zhang Tsu-Chien Weng School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China Center for Transformative Science ShanghaiTech UniversityShanghai 201210China State Key Lab of Fine Chemicals Institute of Artificial PhotosynthesisDUT-KTH Joint Education and Research Center on Molecular DevicesDalian University of Technology(DUT)Dalian 116024China State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China

The migration of protons during the oxygen evolution reaction(OER)is a key factor that affects the performance of OER *** enhance proton transportation,we designed a catalyst based on nickel/iron-pyromellitic acid(NiFe-PMA)prepared by the electrochemical deposition *** catalyst exhibited a low overpotential of 188 mV at a current density of 10 mA·cm^(-2),a Tafel slope of 28.2 mV·dec^(-1),and long-term stability for 30 days with a current of 50 mA·cm^(-2).We characterized the NiFe-PMA catalyst using various techniques,including Fourier transform infrared(FTIR)spectroscopy,Raman spectroscopy,X-ray photoelectron spectroscopy(XPS),X-ray absorption spectroscopy(XAS),transmission electron microscopy(TEM),scanning electron microscopy(SEM),and inductively coupled plasma-optical emission spectrometry(ICP-OES).Our results showed that NiFe-PMA contains nickel,iron atoms,and both coordinated and uncoordinated carboxylate ***,XPS data confirmed that carboxylate ligands could adjust the outer electronic structure of metal ions,resulting in the high valence state of Ni in *** result of XAS indicated that the nickel atoms present in the catalyst might be easier to maintain a higher chemical *** investigations using kinetic isotope effects(KIEs)and proton inventory revealed that the uncoordinated carboxylic protons played a crucial role in receiving protons during the OER,which promoted the proton transfer of the rate-determining step of the *** novel electrocatalysts provide a new strategy for designing more active and cost-effective catalysts for the OER.

关键词： nickel/iron-pyromellitic acid oxygen evolution reaction kinetic isotope effects

Phosphorylated cellulose nanofibers establishing reliable ion-sieving barriers for durable lithium-sulfur batteries

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Journal of Energy Chemistry 2024年第5期92卷 619-628页

作者： Zihao li Pengsen Qian Hongyang li He Xiao Jun Chen Gaoran li School of Materials Science and Engineering Nanjing University of Science and TechnologyNanjing 210094JiangsuChina National Forestry and Grassland Administration Key Laboratory of Plant Fiber Functional Materials Fuzhou 350108FujianChina

The shuttle effect is among the most characteristic and formidable challenges in the pursuit of high-performance lithium-sulfur(li-S)***,phosphorylated cellulose nanofibers(pCNF)are intentionally engineered to establish an ion-sieving barrier against polysulfide shuttling and thereby improve battery *** phosphorylation,involving the grafting of phosphate groups onto the cellulose backbone,imparts an exceptional electronegativity that repels the polysulfide anions from penetrating through the ***,the electrolyte wettability and li^(+)transfer can be significantly promoted by the polar nature of pCNF and the facile li^(+)*** such,rational ion management is realized,contributing to enhanced reversibility in both sulfur and lithium *** a result,li-S cells equipped with the self-standing pCNF separator demonstrate outstanding long-term cyclability with a minimum fading rate of 0.013%per cycle over 1000 cycles at 1 C,and a decent areal capacity of 5.37 mA h cm^(-2) even under elevated sulfur loading of 5.0 mg cm^(-2) and limited electrolyte of 6.0 mL g^(-1).This work provides a facile and effective pathway toward the well-tamed shuttle effect and highly durable li-S batteries.

关键词： lithium-sulfur batteries Cellulose Phosphorylation Ion-sieving Shuttle effect

Progress of gaseous arsenic removal from flue gas by adsorption:Experimental and theoretical calculations

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Journal of Environmental Sciences 2024年第2期136卷 470-485页

作者： Xuelei Yan Qingzhu li Xiaowei Huang Bensheng li Shengtu li Qingwei Wang School of Metallurgy and Environment Central South UniversityChangsha 410083China National Engineering Research Centre for Control and Treatment of Heavy Metal Pollution Central South UniversityChangsha 410083China National Engineering Research Center for Rare Earth Materials General Research Institute for Non-Ferrous MetalsBeijing 100088China

Because of its high mobility and difficult capture,gaseous arsenic pollution control has become the focus of arsenic pollution *** mainly exists in the form of highly toxic As_(2)O_(3)in the flue ***,removing gaseous As_(2)O_(3)from flue gas is of great practical significance for arsenic pollution *** gaseous As_(2)O_(3)on the surface of adsorbents by physical or chemical adsorption is an effective way to reduce the content of arsenic in the flue gas and alleviate arsenic *** the past few decades,various adsorbents have been developed to capture gaseous As_(2)O_(3)in the flue gas,and their adsorption mechanisms have been studied in ***,it is necessary to review the strategies of arsenic removal from flue gas by adsorption,which can inspire further *** on summarizing the morphological distribution of gaseous As_(2)O_(3)in the flue gas,this review further summarizes the removal of gaseous As_(2)O_(3)by several adsorbents and the effect of temperature and the main components of the flue gas on arsenic *** addition,the mechanism of arsenic removal based on adsorption in the flue gas is discussed in depth through theoretical calculations,which is the particular focus of this ***,prospects based on the present research state of arsenic removal by adsorption are proposed to provide ideas for developing effective and stable adsorbents for arsenic removal from flue gas.

关键词： Gaseous arsenic Flue gas Adsorption Theoretical calculation Mechanism

Alignment efficient image-sentence retrieval considering transferable cross-modal representation learning

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Frontiers of Computer Science 2024年第1期18卷 77-91页

作者： Yang YANG Jinyi GUO Guangyu li Lanyu li Wenjie li Jian YANG School of Computer Science and Engineering Nanjing University of Science and TechnologyNanjing 210094China Department of Computing Hong Kong Polytechnic UniversityHong Kong 100872China State Key Lab.for Novel Software Technology Nanjing UniversityNanjing 210094China 14th Research Institute of China Electronics Technology Group Corporation Nanjing 210094China guangyu.li2017@***

Traditional image-sentence cross-modal retrieval methods usually aim to learn consistent representations of heterogeneous modalities,thereby to search similar instances in one modality according to the query from another modality in *** basic assumption behind these methods is that parallel multi-modal data(i.e.,different modalities of the same example are aligned)can be obtained in *** other words,the image-sentence cross-modal retrieval task is a supervised task with the alignments as ***,in many real-world applications,it is difficult to realign a large amount of parallel data for new scenarios due to the substantial labor costs,leading the non-parallel multi-modal data and existing methods cannot be used *** the other hand,there actually exists auxiliary parallel multi-modal data with similar semantics,which can assist the non-parallel data to learn the consistent ***,in this paper,we aim at“Alignment Efficient Image-Sentence Retrieval”(AEIR),which recurs to the auxiliary parallel image-sentence data as the source domain data,and takes the non-parallel data as the target domain *** single-modal transfer learning,AEIR learns consistent image-sentence cross-modal representations of target domain by transferring the alignments of existing parallel ***,AEIR learns the image-sentence consistent representations in source domain with parallel data,while transferring the alignment knowledge across domains by jointly optimizing a novel designed cross-domain cross-modal metric learning based constraint with intra-modal domain adversarial ***,we can effectively learn the consistent representations for target domain considering both the structure and semantic ***,extensive experiments on different transfer scenarios validate that AEIR can achieve better retrieval results comparing with the baselines.

关键词： image-sentence retrieval transfer learning semantic transfer structure transfer

li_(2)ZnTi_(3)O_(8)as the host–separator modifier with efficient polysulfides trapping and fast li^(+)diffusion for lithium-sulfur batteries

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Nano Research 2024年第7期17卷 6087-6094页

作者： Mao Qian Yakun Tang Lang liu Yue Zhang Xiaohui li JiaJia Chen State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources Xinjiang UniversityUrumqi 830017China State Key Laboratory of Physical Chemistry of Solid Surfaces Xiamen UniversityXiamen 361005China

The diffusion and loss of lithium polysulfides(liPSs)in lithium-sulfur batteries(LSBs)reduce the sulfur utilization rate and the catalytic conversion efficiency of sulfur species,resulting in early battery ***_(2)ZnTi_(3)O_(8)(LZTO),characterized by its stable spinel structure,exhibits high li+conductivity and holds great potential as an effective adsorbent for *** study proposes a collaborative design concept of LZTO host–separator modifier,which offers a complementary and matching approach in the cathode side,effectively addressing the challenges associated with dissolution and inadequate conversion of *** functional theory(DFT)calculation substantiates the pronounced chemical affinity of LZTO towards *** importantly,the high efficiency ion transport channels are achieved in separator coating due to the presence of the LZTO ***,the catalytic efficacy of LZTO is validated through meticulous analysis of symmetric batteries and Tafel ***,the LZTO host–separator modifier-based cell displays satisfactory rate capability(1449 and 1166 mAh·g^(−1)at 0.1 and 0.5 C)and an impressively capacity(606 mAh·g^(−1)after 500 cycles at 1 C).The coordinated strategy of host–separator modifier is supposed to have wide applications in LSBs.

关键词： li_(2)ZnTi_(3)O_(8) lithium-sulfur batteries host-separator modifier catalytic conversion diffusion and loss of liPSs

GO/Fe_3O_4/ZnO的制备及其光助Fenton降解苯酚

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工业水处理 2017年第2期37卷 51-55页

作者：李成希吴坤坤孟祖超刘祥李谦定宋久旭西安石油大学化学化工学院陕西西安710065 西安石油大学电子工程学院陕西西安710065

采用水热法制备了GO/Fe_3O_4/ZnO复合材料,并用SEM、FT-IR、XRD等手段对其进行了表征。以苯酚为降解目标,探讨了GO/Fe_3O_4/ZnO复合材料用量、H_2O_2投加量、苯酚浓度和pH等因素对降解苯酚效果的影响。实验结果表明,在GO/Fe_3O_4/ZnO投... 详细信息

采用水热法制备了GO/Fe_3O_4/ZnO复合材料,并用SEM、FT-IR、XRD等手段对其进行了表征。以苯酚为降解目标,探讨了GO/Fe_3O_4/ZnO复合材料用量、H_2O_2投加量、苯酚浓度和pH等因素对降解苯酚效果的影响。实验结果表明,在GO/Fe_3O_4/ZnO投加量为200 mg/L,H_2O_2投加量为12 mmol/L,pH=7.2的条件下,利用该复合材料对苯酚质量浓度为88.85 mg/L的油田污水进行光催化Fenton降解,60 min后,苯酚降解率可达98%。

关键词：石墨烯光催化 Fenton体系可见光

A li_(3)P nanoparticle dispersion strengthened ultrathin li metal electrode for high energy density rechargeable batteries

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Nano Research 2024年第5期17卷 4031-4038页

作者： lin Fu Xiancheng Wang Bao Zhang Zihe Chen Yuanjian li Yongming Sun Provincial Guizhou Key Laboratory of Green Chemical and Clean Energy Technology School of Chemistry and Chemical EngineeringGuizhou UniversityGuiyang 550025China Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074China School of Physical and Mathematical Sciences Nanyang Technological UniversitySingapore 637371Singapore Institute of Materials Research and Engineering Agency for Science Technology and Research(A*STAR)Singapore 138634Singapore

Achievement of lithium(li)metal anode with thin thickness(e.g.,≤30µm)is highly desirable for rechargeable high energy density ***,the fabrication and application of such thin li metal foil electrode remain challenging due to the poor mechanical processibility and inferior electrochemical performance of metallic ***,mechanico-chemical synthesis of robust ultrathin li/li_(3)P(LLP)composite foils(~15µm)is demonstrated by employing repeated mechanical rolling/stacking operations using red P and metallic li as raw *** in-situ formed li+-conductive li_(3)P nanoparticles in metallic li matrix and their tight bonding strengthen the mechanical durability and enable the successful fabrication of free-standing ultrathin li metal composite ***,it also reduces the electrochemical li nucleation barrier and homogenizes li plating/stripping *** matching to high-voltage liCoO_(2),the full cell with a low negative/positive(N/P)capacity ratio of~1.5 offers a high energy density of~522 W·h·kg^(-1) at 0.5 C based on the mass of cathode and *** into account its facile manufacturing,potentially low cost,and good electrochemical performance,we believe that such an ultrathin composite li metal foil design with nanoparticle-dispersion-strengthened mechanism may boost the development of high energy density li metal batteries.

关键词： lithium metal anode high energy density battery mechanico-chemical synthesis ultrathin li/li_(3)P composite foil low negative/positive capacity ratio