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Robust and intrinsic type-Ⅲnodal points in a diamond-like lattice

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Chinese Physics B 2022年第11期31卷 460-464页

作者： Qing-Ya Cheng yue-e xie Xiao-Hong Yan Yuan-Ping Chen School of Physics and electronic engineering Jiangsu UniversityZhenjiang 212013China School of Physics and Optoelectronics Xiangtan UniversityXiangtan 411105China

An ideal type-Ⅲnodal point is generated by crossing a completely flat band and a dispersive band along a certain momentum *** date,the type-Ⅲnodal points found in two-dimensional(2D)materials have been mostly accidental and random rather than ideal cases,and no one mentions what kind of lattice can produce ideal nodal ***,we propose that ideal type-Ⅲnodal points can be obtained in a diamond-like *** flat bands in the lattice originate from destructive interference of wavefunctions,and thus are intrinsic and ***,the specific lattice can be realized in some 2D carbon networks,such as T-graphene and its *** the carbon structures possess type-ⅢDirac *** two of the structures,consisting of triangular carbon rings,the type-ⅢDirac points are located just on the Fermi level and the Fermi surface is very *** research not only opens a door to finding the ideal type-ⅢDirac points,but also provides 2D materials for exploring their physical properties experimentally.

关键词： diamond-like lattice carbon materials type-ⅢDirac points

Seeing Dirac electrons and heavy fermions in new boron nitride monolayers

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Chinese Physics B 2020年第5期29卷 454-458页

作者： Yu-Jiao Kang Yuan-Ping Chen Jia-Ren Yuan Xiao-Hong Yan yue-e xie School of Physics and Optoelectronics Xiangtan UniversityXiangtan 411105China Faculty of Science Jiangsu UniversityZhenjiang 212013China

Most three-dimensional(3D)and two-dimensional(2D)boron nitride(BN)structures are wide-band-gap ***,we propose two BN monolayers having Dirac points and flat bands,*** monolayer is named as 5-7 BN that consists of five-and seven-membered *** other is a Kagome BN made of triangular boron rings and nitrogen *** two structures show not only good dynamic and thermodynamic stabilities but also novel electronic *** 5-7 BN has Dirac points on the Fermi level,indicating that the structure is a typical Dirac *** Kagome BN has double flat bands just below the Fermi level,and thus there are heavy fermions in the *** flat-band-induced ferromagnetism is also *** analyze the origination of the band structures by partial density of states and projection of *** addition,a possible route to experimentally grow the two structures on some suitable substrates such as the PbO2(111)surface and the CdO(111)surface is also discussed,*** research not only extends understanding on the electronic properties of BN structures,but also may expand the applications of BN materials in 2D electronic devices.

关键词： boron nitride Dirac fermion flat band ferromagnetism

Bilayer twisting as a mean to isolate connected flat bands in a kagome lattice through Wigner crystallization

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Chinese Physics B 2021年第7期30卷 5-10页

作者： Jing Wu yue-e xie Ming-Xing Chen Jia-Ren Yuan Xiao-Hong Yan Sheng-Bai Zhang Yuan-Ping Chen School of Physics and Optoelectronics Xiangtan UniversityXiangtan 411105China Faculty of Science Jiangsu UniversityZhenjiang 212013China School of Physics and electronics Hunan Normal UniversityChangsha 410081China Department of Physics Applied Physicsand Astronomy Rensselaer Polytechnic InstituteTroyNew York 12180USA

The physics of flat band is novel and rich but difficult to *** this regard,recently twisting of bilayer van der Waals(vd W)-bounded two-dimensional(2 D)materials has attracted much attention,because the reduction of Brillouin zone will eventually lead to a diminishing kinetic ***,one may start with a 2 D kagome lattice,which already possesses flat bands at the Fermi level,but unfortunately these bands connect quadratically to other(dispersive)bands,leading to undesirable ***,we propose,by first-principles calculation and tight-binding modeling,that the same bilayer twisting approach can be used to isolate the kagome flat *** the starting kinetic energy is already vanishingly small,the interlayer vd W potential is always sufficiently large irrespective of the twisting *** such the electronic states in the(connected)flat bands become unstable against a spontaneous Wigner crystallization,which is expected to have interesting interplays with other flat-band phenomena such as novel superconductivity and anomalous quantum Hall effect.

关键词： twisted bilayer kagome graphene flat bands Wigner crystallization

An efficient Boron Source Activation Strategy for the Low‑Temperature Synthesis of Boron Nitride Nanotubes

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Nano-Micro Letters 2025年第1期17卷 548-558页

作者： Ying Wang Kai Zhang Liping Ding Liyun Wu Songfeng e Qian He Nanyang Wang Hui Zuo Zhengyang Zhou Feng Ding yue Hu Jin Zhang Yagang Yao National Laboratory of Solid State Microstructures College of Engineering and Applied SciencesJiangsu Key Laboratory of Artificial Functional Materialsand Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093People’s Republic of China School of electronic Information and Artificial Intelligence Shaanxi University of Science&TechnologyXian 710000People’s Republic of China College of Bioresources Chemical and Materials engineering Shaanxi University of Science&TechnologyXian 710000People’s Republic of China Key Laboratory of Carbon Materials of Zhejiang Province College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325000People’s Republic of China Shenzhen Institutes of Advanced Technology Chinese Academy of SciencesShenzhen 518000People’s Republic of China College of Chemical and Molecular engineering Peking UniversityBeijing 100871People’s Republic of China

Lowering the synthesis temperature of boron nitride nanotubes(BNNTs)is crucial for their *** primary reason for adopting a high temperature is to enable the effective activation of highmelting-point solid *** this study,we developed a novel approach for efficiently activating boron by introducing alkali metal compounds into the conventional MgO–B *** approach can be adopted to form various low-melting-point AM–Mg–B–O growth *** growth systems have improved catalytic capability and reactivity even under low-temperature conditions,facilitating the synthesis of BNNTs at temperatures as low as 850℃.In addition,molecular dynamics simulations based on density functional theory theoretically demonstrate that the systems maintain a liquid state at low temperatures and interact with N atoms to form BN *** findings offer novel insights into the design of boron activation and are expected to facilitate research on the low-temperature synthesis of BNNTs.

关键词： Boron nitride nanotubes Low-temperature Boron activation Density functional theory

Ubiquitination in Abscisic Acid-Related Pathway

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Journal of Integrative Plant Biology 2007年第1期49卷 87-93页

作者： Yi-yue Zhang Qi xie State Key Laboratory of Plant Genomics Institute of Genetics and Developmental Biology the Chinese Academy of Sciences Beijing 100101 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China

Ubiquitination is emerging as a tight regulatory mechanism that is necessary for all aspects of development and survival of all eukaryotes. Recent genomic and genetic analysis in Arabidopsis suggests that ubiquitination may also play important roles in plant response to the phytohormone abscisic acid （ABA）. Many components of the ubiquitination pathway, such as ubiquitin-conjugating enzyme e2, ubiquitin ligase e3 and components of the proteasome, have been identified or predicted to be essential in ABA biosynthesis, catabolism and signaling. In addition, the ubiquitination-related pathway, sumoylation, is also involved in ABA signaling. We summarize in this report recent developments to elucidate their roles in the ABA-related pathway.

关键词： ABA e3 ligase proteolysis SUMO ubiquitination ubiquitin-conjugating enzyme (e2)

Arsenite Removal from Simulated Groundwater by Biogenic Schwertmannite: A Column Trial

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Pedosphere 2013年第3期23卷 402-408页

作者： xie yue ZHOU Li-Xiang Department of environmental engineering College of Resources and Environmental Sciences Nanjing Agricultural University

To assess the feasibility of biogenic schwertmannite to act as a sorbent for removing arsenite from groundwater, a series of biogenic schwertmannite-packed column adsorption experiments were conducted on simulated As（III）-containing groundwater. empty bed contact time （eBCT）, As（III） concentration in effluent, and the removal efficiency of As（III） through the column were investigated at pH 8.0 and temperature 25 ± 0.5 ℃. The results showed that the breakthrough curves were mainly dependent on eBCT values when the influent As（III） concentration was 500 μg L-1 and the optimum eBCT was 4.0 min. When the effluent As（III） concentration reached 10 and 50 μg L-1, the breakthrough volumes for the schwertmannite adsorption column were 4200 and 5600 bed volume （BV）, with As（III） adsorption capacity of 2.1 and 2.8 mg g-1, respectively. Biogenic schwertmannite could be regenerated by 1.0 mol L-1 NaOH solution, and more than 80% of As（III） adsorbed on the surface of schwertmannite could be released after 3 successive regenerations. The breakthrough volume for the regenerated sehwertmannite-packed column still maintained 4 000-4 200 BV when the As（III） concentration in effluent was below 10 μg L-1. Compared with other sorbents for As（III） removal, the biogenic schwertmannite- packed column had a higher breakthrough volume and a much higher adsorption capacity, implying that biogenic schwertmannite was a highly efficient and potential sorbent to purify As（III）-contaminated groundwater.

关键词： adsorption capacity As(III) breakthrough volume empty bed contact time sorbent

基于稀疏注意力卷积ViT模型的锌浮选工况识别

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工程科学学报 2025年第2期47卷 328-338页

作者：苏越唐朝晖谢永芳高小亮张虎马炜烨汤海玚中南大学自动化学院中南大学数学与统计学院

准确识别锌浮选工况并用于指导锌浮选操作，可以提高浮选效率、优化选矿过程.目前浮选现场主要通过人工肉眼观察泡沫并依据经验判断工况，这种方法主观性强，难以客观准确地评价锌浮选工况.针对该问题，本文通过研究锌浮选泡沫视觉特征... 详细信息

准确识别锌浮选工况并用于指导锌浮选操作，可以提高浮选效率、优化选矿过程.目前浮选现场主要通过人工肉眼观察泡沫并依据经验判断工况，这种方法主观性强，难以客观准确地评价锌浮选工况.针对该问题，本文通过研究锌浮选泡沫视觉特征和浮选工况的密切联系，提出基于稀疏注意力卷积ViT模型的锌浮选工况识别方法.首先，所提模型融合了卷积神经网络（Convolutional neural networks, CNN）和视觉Transformer(Vision transformer,ViT)的结构和优点，同时感知泡沫局部空间信息和全局信息，完备表征泡沫图像.其次，模型引入稀疏的多头注意力机制，每个注意力头以不同的稀疏程度处理特征，从不同尺度下感知全局信息，同时引入注意力门控单元优化特征传递，最终实现锌浮选工况识别.实验结果表明，本文所提工况识别方法在锌浮选泡沫图像数据集上的准确率达到88.62%，解决了传统CNN和ViT模型不能充分利用泡沫图像全局信息，且无法自适应捕捉泡沫图像重要特征的问题，为浮选流程优化提供有力支持.

关键词：工况识别卷积神经网络视觉Transformer 稀疏注意力泡沫浮选

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Almansi-Type Decomposition Theorem for Bi-k-regular Functions in the Clifford Algebra Cl_(2n+2,0)(R)

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Chinese Annals of Mathematics,Series B 2022年第2期43卷 253-264页

作者： Lixia LIU yue LIU Yonghong xie School of Mathematical Sciences Hebei Normal UniversityShijiazhuang 050024China

Almansi-type decomposition theorem for bi-k-regular functions defined in a star-like domainΩ⊆R^(n+1)×R^(n+1)centered at the origin with values in the Clifford algebra Cl_(2n+2,0)(R)is *** a corollary,Almansi-type de... 详细信息

关键词： Real Clifford analysis Biregular functions Bi-k-regular functions Almansi-type decomposition theorem

Study on the hydrogen absorption properties of a YGdTbDyHo rare-earth high-entropy alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 127-135页

作者： Tongyue Li Ziliang xie Wenjiao Zhou Huan Tong Dawen Yang Anjia Zhang Yuan Wu Xiping Song State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China Whole Win(Beijing)Materials Sci.&Tech.Co. Ltd.Beijing 100083China

This study investigated the microstructure and hydrogen absorption properties of a rare-earth high-entropy alloy(HeA),*** indicated that the YGdTbDyHo alloy had a microstructure of equiaxed grains,with the alloy elements distributed *** hydrogen absorption,the phase structure of the HeA changed from a solid solution with an hexagonal-close-packed(HCP)structure to a high-entropy hydride with an faced-centered-cubic(FCC)structure without any secondary phase *** alloy demonstrated a maximum hydrogen storage capacity of 2.33 H/M(hydrogen atom/metal atom)at 723 K,with an enthalpy change(ΔH)of-141.09 kJ·mol^(-1)and an entropy change(ΔS)of-119.14 J·mol^(-1)·K^(-1).The kinetic mechanism of hydrogen absorption was hydride nucleation and growth,with an apparent activation energy(e_(a))of 20.90 kJ·mol^(-1).Without any activation,the YGdTbDyHo alloy could absorb hydrogen quickly(180 s at 923 K)with nearly no incubation period *** reason for the obtained value of 2.33 H/M was that the hydrogen atoms occupied both tetrahedral and octahedral *** results demonstrate the potential application of HeAs as a high-capacity hydrogen storage material with a large H/M ratio,which can be used in the deuterium storage field.

关键词： rare-earth high-entropy alloy hydrogen absorption capacity pressure–composition–temperature curves kinetics