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Parity-dependent skin effects and topological properties in the multilayer nonreciprocal su−Schrieffer−Heeger structures

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Frontiers of physics 2024年第3期19卷 115-133页

作者： Jia-Rui Li Cui Jiang Han su Di Qi lian-lian Zhang Wei-Jiang Gong College of Sciences Northeastern UniversityShenyang 110819China Basic Department Shenyang Institute of EngineeringShenyang 110136China

We concentrate on the skin effects and topological properties in the multilayer non-Hermitian su−Schrieffer−Heeger (SSH) structure, by taking into account the nonreciprocal couplings between the different sublattices in the unit cells. Following the detailed demonstration of the theoretical method, we find that in this system, the skin effects and topological phase transitions induced by nonreciprocal couplings display the apparent parity effect, following the increase of the layer number of this SSH structure. On the one hand, the skin effect is determined by the parity of the layer number of this SSH system, as well as the parity of the band index of the bulk states. On the other hand, for the topological edge modes, such an interesting parity effect can also be observed clearly. Next, when the parameter disorders are taken into account, the zero-energy edge modes in the odd-layer structures tend to be more robust, whereas the other edge modes are easy to be destroyed. In view of these results, it can be ascertained that the findings in this work promote to understand the influences of nonreciprocal couplings on the skin effects and topological properties in the multilayer SSH lattices.

关键词： multilayer SSH lattice nonreciprocal couplings band structure skin effect

Methyl Halide to Olefins and Gasoline over Zeolites and SAPO Catalysts：A New Route of MTO and MTG

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催化学报 2012年第1期33卷 11-21页

作者： WEI Yingxu ZHANG Dazhi LIU Zhongmin su bao-lian Dalian National Laboratory for Clean Energy National Engineering Laboratory for Methanol-to-OlefinsDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 0LiaoningChina Laboratory of Inorganic Materials Chemistry(CMI) University of Namur(FUNDP)61rue de BruxellesB-5000NamurBelgium State Key Laboratory of Advanced Technology for Material Synthesis and Processing Wuhan University of TechnologyWuhan 430070HubeiChina

到更有用的更高的烃的甲烷的合理、有效的变换是天然气利用的最重要的话题之一。尽管到珍贵混合物的甲烷激活和它的变换吸引增加的注意，甲烷变换经常为 syngas 通过消费精力的步以间接方法被做从甲烷改过的蒸气的生产。一些有希望的结... 详细信息

到更有用的更高的烃的甲烷的合理、有效的变换是天然气利用的最重要的话题之一。尽管到珍贵混合物的甲烷激活和它的变换吸引增加的注意，甲烷变换经常为 syngas 通过消费精力的步以间接方法被做从甲烷改过的蒸气的生产。一些有希望的结果看起来为从甲烷的高增值产品的生产具有为一种选择和潜在的线路的发展的意义。到更高的烃的甲烷的有效变换能作为中介经由甲基卤化物被认识到。在 halomethane 的生产以后，他们能在修改沸石和 SAPO 上被转变到汽油和轻石蜡分子的筛。高变换效率和选择显示了工业申请的可行性。研究在基本研究和工业申请从观点获得了最近成长的兴趣。反应机制上的学习从甲基卤化物使 CC 契约建设的可能的线路清楚些，它是到更高的烃的 C1 反应物变换的重要问题。氢卤化物产生没在反应机制和催化剂的结构稳定性上在甲基卤化物变换期间施加明显的影响。这评论处理这个领域和注释的进化要探索的优点和缺点经由甲基卤化物发送为新、持续的 methane-to-olefins (MTO ) 和 methane-to-gasoline (MTG ) 的开发被阻止。

关键词： methyl halides hydrocarbons zeolite SAPO-34 reaction mechanism

Low-Rank Optimal Transport for Robust Domain Adaptation

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IEEE/CAA Journal of Automatica Sinica 2024年第7期11卷 1667-1680页

作者： Bingrong Xu Jianhua Yin Cheng lian Yixin su Zhigang Zeng IEEE the School of Automation Wuhan University of TechnologyWuhan 430070China Intelligent Transportation Systems Research Center Wuhan University of TechnologyWuhan 430063 Chongqing Research Institute Wuhan University of TechnologyChongqingChina the School of Artificial Intelligence and Automation Huazhong University of Science and TechnologyWuhan 430074 the Key Laboratory of Image Processing and Intelligent Control of Education Ministry of China Wuhan 430074China

When encountering the distribution shift between the source(training) and target(test) domains, domain adaptation attempts to adjust the classifiers to be capable of dealing with different domains. Previous domain adaptation research has achieved a lot of success both in theory and practice under the assumption that all the examples in the source domain are welllabeled and of high quality. However, the methods consistently lose robustness in noisy settings where data from the source domain have corrupted labels or features which is common in reality. Therefore, robust domain adaptation has been introduced to deal with such problems. In this paper, we attempt to solve two interrelated problems with robust domain adaptation:distribution shift across domains and sample noises of the source domain. To disentangle these challenges, an optimal transport approach with low-rank constraints is applied to guide the domain adaptation model training process to avoid noisy information influence. For the domain shift problem, the optimal transport mechanism can learn the joint data representations between the source and target domains using a measurement of discrepancy and preserve the discriminative information. The rank constraint on the transport matrix can help recover the corrupted subspace structures and eliminate the noise to some extent when dealing with corrupted source data. The solution to this relaxed and regularized optimal transport framework is a convex optimization problem that can be solved using the Augmented Lagrange Multiplier method, whose convergence can be mathematically proved. The effectiveness of the proposed method is evaluated through extensive experiments on both synthetic and real-world datasets.

关键词： Domain adaptation low-rank constraint noise corruption optimal transport

Exploring the impacts of major events on the systemic risk of the international energy market

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Petroleum Science 2024年第2期21卷 1444-1457页

作者： Ming-Tao Zhao su-Wan Lu lian-Biao Cui School of Statistics and Applied Mathematics Anhui University of Finance and EconomicsBengbu233030AnhuiChina Anhui Province Key Laboratory of Philosophy and Social Science of Low-Carbon Development and Carbon Finance Anhui University of Finance and EconomicsBengbu233030AnhuiChina

This study examines the systemic risk caused by major events in the international energy market(IEM)and proposes a management strategy to mitigate it. Using the tail-event driven network(TENET)method, this study constructed a tail-risk spillover network(TRSN) of IEM and simulated the dynamic spillover tail-risk process through the cascading failure mechanism. The study found that renewable energy markets contributed more to systemic risk during the Paris Agreement and the COVID-19pandemic, while fossil energy markets played a larger role during the Russia-Ukraine conflict. This study identifies systemically important markets(SM) and critical tail-risk spillover paths as potential sources of systemic risk. The research confirms that cutting off the IEM risk spillover path can greatly reduce systemic risk and the influence of SM. This study offers insights into the management of systemic risk in IEM and provides policy recommendations to reduce the impact of shock events.

关键词： International energy market Tail-risk spillover Cascading failure mechanism Systemic risk management

Alleviating the anisotropic microstructural change and boosting the lithium ions diffusion by grain orientation regulation for Ni-rich cathode materials

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Journal of Energy Chemistry 2024年第1期88卷 213-222,I0005页

作者： Xinyou He Shilin su bao Zhang Zhiming Xiao Zibo Zhang Xing Ou Engineering Research Center of the Ministry of Education for Advanced Battery Materials School of Metallurgy and EnvironmentCentral South UniversityChangsha 410083HunanChina Zhejiang Power New Energy Co.Ltd Zhuji 311899ZhejiangChina

Generally,layered Ni-rich cathode materials exhibit the morphology of polycrystalline secondary sphere composed of numerous primary *** the arrangement of primary particles plays a very important role in the properties of Ni-rich *** disordered particle arrangement is harmful to the cyclic performance and structural stability,yet the fundamental understanding of disordered structure on the structural degradation behavior is ***,we have designed three kinds of LiNi_(0.83)Co_(0.06)Mn_(0.11)O_(2) cathode materials with different primary particle orientations by regulating the precursor coprecipitation *** finite element simulation and in-situ characterization,the Li^(+)transport and structure evolution behaviors of different materials are ***,the smooth Li^(+)diffusion minimizes the reaction heterogeneity,homogenizes the phase transition within grains,and mitigates the anisotropic microstructural change,thereby modulating the crack evolution ***,the optimized structure evolution ensures radial tight junctions of the primary particles,enabling enhanced Li^(+)diffusion during dynamic ***-loop bidirectional enhancement mechanism becomes critical for grain orientation regulation to stabilize the cyclic *** precursor engineering with particle orientation regulation provides the useful guidance for the structural design and feature enhancement of Ni-rich layered cathodes.

关键词： Ni-rich cathode Grain orientation regulation Anisotropic microstructural change Precursor engineering Li~+-ions diffusion

Critical Role of Ethylene-Propylene Block Copolymer in Impact Polypropylene Copolymer

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Chinese Journal of Polymer Science 2024年第3期42卷 344-351,I0007页

作者： Yu-Hui Tang Na Zhang Wei bao Wei Jiang Yuan Lin Zhao-Hui su State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China

Ethylene-propylene block copolymer(EbP) is a vital component in impact polypropylene copolymer(IPC), yet its distribution in the multiphase composite material and how it influences the phase structure and the mechanical properties are not well understood. In this work,four IPCs were investigated by atomic force microscopy-infrared(AFM-IR) to assess the phase compositions in situ, based on which in conjunction with the chain microstructure information obtained ex situ the distributions of the copolymer components were derived for each alloy. For the IPCs whose EbP comprises long P and long E segments, the EbP fraction was found to phase separate from the rubber and the PP matrix to form the cores of the disperse particles with the E-P segmented copolymer(EsP). In contrast, in the IPC with EbP composed of long P and short E segments, the EbP fraction formed an outer shell for the rubber particles with the cores comprising the EsP alone, and this IPC, containing a lower E comonomer content than its counterpart, exhibited both better impact resistance and higher flexural modulus. These results clarify how the chain structure of EbP governs the phase morphology in IPC, which in turn impacts the properties of the composite material.

关键词： Impact polypropylene copolymers AFM-IR Ethylene-propylene block copolymers Core-shell rubber particles

Simultaneous integration of Fe clusters and NiFe dual single atoms in nitrogen-doped carbon for oxygen reduction reaction

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Nano Research 2024年第4期17卷 2291-2297页

作者： Jirong Bai Yuebin lian Yaoyao Deng Mei Xiang Peng Xu Quanfa Zhou Yawen Tang Yaqiong su Research Center of Secondary Resources and Environment School of Chemical Engineering and MaterialsChangzhou Institute of TechnologyChangzhou 213022China Jiangsu Key Laboratory of New Power Batteries School of Chemistry and Materials ScienceNanjing Normal UniversityNanjing 210023China School of Chemistry Engineering Research Center of Energy Storage Materials and Devices of Ministry of EducationNational Innovation Platform(Center)for Industry-Education Integration of Energy Storage TechnologyXi’an Jiaotong UniversityXi’an 710049China

Atomically-dispersed iron-based electrocatalysts are promising substitutes for noble metal electrocatalysts because of excellent performance in oxygen reduction reaction(ORR).Rationally modulating the local coordination environment of the Fe site and optimizing the binding energy of oxygen reduction intermediates are effective strategies to optimize ORR ***,we report a new method in which Ni is introduced to construct NiFe dual single atoms and iron nanoclusters loaded on the nitrogen-doped carbon with a highly porous *** design plays a synergistic role of dual single atoms and clusters,optimizes the 3d orbital and Fermi level of Fe,breaks the symmetrical structure of Fe-N_(4),and effectively improves the adsorption/desorption behavior of the oxygen-containing *** tests show FeNCs/NiFeSAs-NC has an excellent intrinsic *** calculations show the oxygen-containing species on the Ni active site will move to the middle of NiFe(bridge site connection)after optimization and that the key step is OH desorption,with a reaction energy of 0.27 *** electron exchange between NiFe-N6 and Fe-cluster is very strong,further indicating the introduction of Ni species and Fe clusters has a regulatory effect on the electronic structure of Fe-N_(4).

关键词： NiFe dual single atoms Fe clusters OH*adsorption energy oxygen reduction reaction

Precise Planar-Twisted Molecular Engineering to Construct Semiconducting Polymers with Balanced Absorption and Quantum Yield for Efficient Phototheranostics

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Research 2024年第2期2023卷 227-238页

作者： Xiang su Zhirong bao Wei Xie Deliang Wang Ting Han Dong Wang Ben Zhong Tang Center for AIE Research Shenzhen Key Laboratory of Polymer Science and TechnologyGuangdong Research Center for Interfacial Engineering of Functional MaterialsCollege of Materials Science and EngineeringShenzhen UniversityShenzhen 518060China School of Biomedical and Pharmaceutical Sciences Guangdong University of TechnologyGuangzhou 510006China Department of Radiation and Medical Oncology Hubei Key Laboratory of Tumor Biological BehaviorsHubei Cancer Clinical Study CenterZhongnan Hospital of Wuhan UniversityWuhan 430071China Department of Materials Chemistry Huzhou UniversityHuzhou 313000China School of Science and Engineering Shenzhen Institute of Aggregate Science and TechnologyThe Chinese University of Hong KongShenzhenGuangdong 518172China

Semiconducting polymers(SPs)have shown great feasibility as candidates for near-infrared-II(NIR-Ⅱ)fluorescence imaging-navigated photothermal therapy due to their strong light-harvesting ability and flexible ***,the fluorescence signal of traditional SPs tends to quench in their aggregate states owing to the strongπ-πstacking,which can lead to the radiative decay pathway shutting *** address this issue,aggregation-induced emission effect has been used as a rational tactic to boost the aggregate-state fluorescence of NIR-Ⅱ*** this contribution,we developed a precise molecular engineering tactic based on the block copolymerizations that integrate planar and twisted segments into one conjugated polymer backbone,providing great flexibility in tuning the photophysical properties and photothermal conversion capacity of *** monomers featured with twisted and planar architectures,respectively,were tactfully incorporated via a ternary copolymerization approach to produce a series of new *** optimal copolymer(SP2)synchronously shows desirable absorption ability and good NIR-Ⅱquantum yield on the premise of maintaining typical aggregation-induced emission characteristics,resulting in balanced NIR-Ⅱfluorescence brightness and photothermal ***-dispersible nanoparticles fabricated from the optimal SP2 show efficient photothermal therapeutic effects both in vitro and in *** in vivo investigation reveals the distinguished NIR-Ⅱfluorescence imaging performance of SP2 nanoparticles and their photothermal ablation toward tumor with prominent tumor accumulation ability and excellent biocompatibility.

关键词： property. conducting twisted

Acid-rock reaction kinetics in a two-scale model based on reaction order correction

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Petroleum Science 2024年第3期21卷 2089-2101页

作者： Xue-Song Li Ning Qi Ze-Hui Zhang lian Liu Xia-Qing Li Xu-Hang su School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongChina Key Lab of Unconventional Oil&Gas Development Ministry of EducationChina University of Petroleum(East China)Qingdao26650ShandongChina SINOPEC Northwest Oilfield Branch Company Urumqi830011XinjiangChina Petroleum Engineering Technology Research Institute SINOPEC Shengli Oilfield CompanyDongying257000ShandongChina

The reaction order plays a crucial role in evaluating the response rate of ***,the conventional two-scale model typically assumes that the reaction order is constant as one,which can lead to significant deviations from *** address this issue,this study proposes a novel multi-order dynamic model for acid-rock reaction by combining rotating disk experimental data with theoretical *** numerical simulations,this model allows for the investigation of the impact of acidification conditions on different orders of reaction,thereby providing valuable insights for on-site *** analysis reveals that higher response orders require higher optimal acid liquid flow rates,and lower optimal H+diffusion coefficients,and demonstrate no significant correlation with acid ***,it is recommended to increase the displacement and use high-viscosity acid for reservoirs with high calcite content,while reducing the displacement and using low-viscosity acid for reservoirs with high dolomite content.

关键词： Reaction order Two-scale model Wormhole propagation Carbonate rocks Numerical simulation