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Eigenstate properties of the disordered Bose-Hubbard chain

Frontiers of physics 2024年第4期19卷 57-72页

作者： Jie chen Chun chen Xiaoqun Wang Key Laboratory of Artificial Structures and Quantum Control(Ministry of Education) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China School of Physics Zhejiang UniversityHangzhou 310058China Collaborative Innovation Center of Advanced Microstructures Nanjing UniversityNanjing 210093China

Many-body localization(MBL)of a disordered interacting boson system in one dimension is studied numerically at the filling faction *** von Neumann entanglement entropy Svn is commonly used to detect the MBL phase transition but remains challenging to be directly *** on the U(1)symmetry from the particle number conservation,Svn can be decomposed into the particle number entropy S_(n) and the configuration entropy *** light of the tendency that the eigenstate's S_(c) nears zero in the localized phase,we introduce a quantity describing the deviation of S from the ideal thermalization distribution;finite-size scaling analysis illustrates that it shares the same phase transition point with Sv but displays the better critical *** observation hints that the phase transition to MBL might largely be determined by S and its fluctuations Notably,the recent experiments[***,et al.,Science 364,256(2019);***,et al.,***.19,481(2023)]demonstrated that this deviation can potentially be measured through the Sn ***,our investigations reveal that the thermalized states primarily occupy the low-energy section of the spectrum,as indicated by measures of localization length,gap ratio,and energy density *** low-energy spectrum of the Bose model closely resembles the entire spectrum of the Fermi(or spin XXZ)model,accommodating a transition from the thermalized to the localized ***,owing to the bosonic statistics,the high-energy spectrum of the model allows the formation of distinct clusters of bosons in the random potential *** analyze the resulting eigenstate properties and briefly summarize the associated *** distinguish between the phase regions at the low and high energies,a probing quantity based on the structure of S_(VN) is also *** work highlights the importance of symmetry combined with entanglement in the study of *** this regard,for the disordered Heisenberg XXZ

关键词： entanglement entropy decomposition U(1)symmetry thermalization-to-localization transition

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Neural networks-based iterative learning control consensus for periodically time-varying multi-agent systems

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Science China(Technological Sciences) 2024年第2期67卷 464-474页

作者： chen JiaXi LI JunMin chen WeiSheng GAO WeiFeng School of Mathematics and Statistics Xidian UniversityXi'an 710071China School of Aerospace Science and Technology Xidian UniversityXi'an 710071China

In this paper,the problem of adaptive iterative learning based consensus control for periodically time-varying multi-agent systems is studied,in which the dynamics of each follower are driven by nonlinearly parameterized terms with periodic *** networks and Fourier base expansions are introduced to describe the periodically time-varying dynamic *** this basis,an adaptive learning parameter with a positively convergent series term is constructed,and a distributed control protocol based on local signals between agents is designed to ensure accurate consensus of the closed-loop ***,consensus algorithm is generalized to solve the formation control ***,simulation experiments are implemented through MATLAB to demonstrate the effectiveness of the method used.

关键词： multi-agent systems adaptive iterative learning control nonlinearly parameterized dynamics Fourier series expansion neural networks

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GENERALIZED JACOBI SPECTRAL GALERKIN METHOD FOR FRACTIONAL-ORDER VOLTERRA INTEGRO-DIFFERENTIAL EQUATIONS WITH WEAKLY SINGULAR KERNELS

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Journal of Computational Mathematics 2024年第2期42卷 355-371页

作者： Yanping chen Zhenrong chen Yunqing Huang School of Mathematical Sciences South China Normal UniversityGuangzhou 510631China Hunan Key Laboratory for Computation and Simulation in Science and Engineering Xiangtan UniversityXiangtan 411105China

For fractional Volterra integro-differential equations(FVIDEs)with weakly singular kernels,this paper proposes a generalized Jacobi spectral Galerkin *** basis functions for the provided method are selected generalized Jacobi functions(GJFs),which can be utilized as natural basis functions of spectral methods for weakly singular FVIDEs when appropriately *** developed method's spectral rate of convergence is determined using the L^(∞)-norm and the weighted L^(2)-*** results indicate the usefulness of the proposed method.

关键词： Generalized Jacobi spectral Galerkin method Fractional-order Volterra integ-ro-differential equations Weakly singular kernels Convergence analysis

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Recent Advances in Nickel Catalyzed Carbonylative Reactions via the Insertion of Carbon Monoxide

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Chinese Journal of Chemistry 2024年第2期42卷 177-189页

作者： Xinzhou chen Gang chen Zhong Lian Department of Dermatology State Key Laboratory of Biotherapy and Cancer CenterWest China HospitalSichuan UniversityChengduSichuan 610041China

Carbonyl compounds have attracted considerable attention due to their extensive applications in drug ***,they are important synthetic intermediates for the construction of carbon-carbon and carbon-heteroatom ***-metal-catalyzed carbonylation via the insertion of co is one of the most efficient and straightforward strategies to access carbonyl ***,most of the transition-metal-catalyzed carbonylative reactions require expensive and toxic noble-metal ***,there is a growing demand for the exploration of nickel-catalyzed carbonylative reactions via the insertion of CO due to the earth abundance and low cost of *** with the well-established palladium-catalyzed carbonylative reactions,nickel-catalyzed analogous transformations have been relatively *** is primarily because CO strongly binds to nickel,often resulting in catalyst *** recent years,some research groups have focused on using CO surrogates or NN_(2) pincer nickel catalyst to circumvent the formation of Ni(CO)_(4).Nickel-catalyzed carbonylation has been applied in the construction of carbonyl-containing compounds,such as ketones,carboxylic acids,thioesters,acyl chloride and carboxamides.

关键词： Carbonylation Nickel catalysis Carbon monoxide C1 chemistry Carbonyl-containing compounds

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High-Level Security Dimension Evaluation of Blockchain BaaS System and Key Technology

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China Communications 2024年第6期21卷 176-191页

作者： chen Wanfa Zheng Qing’an chen Shuzhen Fu Hongyi chen Liang Fujian Police College Fuzhou 350007China Computer Science and Information Security Management Department Fujian Police CollegeFuzhou 350007China Fujian Province Key Laboratory for Digital Network Crime Supervision and Prevention Fuzhou 350007China Beijing University of Posts and Telecommunications Beijing 100876China Fujian Provincial Prison Administration Fuzhou 350002China

In recent years,blockchain technology integration and application has gradually become an important driving force for new technological innovation and industrial *** blockchain technology and applications are developing rapidly,the emerging security risks and obstacles have gradually become *** can still find security issues in blockchain systems and conduct attacks,causing increasing losses from network attacks every *** response to the current demand for blockchain application security detection and assessment in all industries,and the insufficient coverage of existing detection technologies such as smart contract detectiontechnology,this paper proposes a blockchain core technology security assessment system model,and studies the relevant detection and assessment key technologies and systems.A security assessment scheme based on a smart contract and consensus mechanism detection scheme is *** the underlying blockchain architecture supports the traceability of detection results using super ***,the functionality and performance of the system were tested,and the test results show that the model and solutions proposed in this paper have good feasibility.

关键词： blockchain security consensus mechanis smart contract

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Blockchain-based immunization against kleptographic attacks

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Science China(Information Sciences) 2024年第7期67卷 172-183页

作者： Changsong JIANG Chunxiang XU Jie chen Kefei chen School of Computer Science and Engineering University of Electronic Science and Technology of China Yangtze Delta Region Institute (Huzhou) University of Electronic Science and Technology of China Department of Mathematics Hangzhou Normal University

Adversarial implementations of cryptographic primitives called kleptographic attacks cause the leakage of secret information. Subliminal channel attacks are one of the kleptographic attacks. In such attacks, backdoors are embedded in implementations of randomized algorithms to elaborately control randomness generation, such that the secrets will be leaked from biased outputs. To thwart subliminal channel attacks, double-splitting is a feasible solution, which splits the randomness generator of a randomized algorithm into two independent generators. In this paper, we instantiate double-splitting to propose a secure randomness generation algorithm dubbed SRG using two physically independent generators: ordinary and public randomness generators. Based on public blockchains, we construct the public randomness generator,which can be verified publicly. Hashes of a sufficient number of consecutive blocks that are newly confirmed on a blockchain are used to produce public randomness. In SRG, outputs from the two generators are taken as inputs of an immunization function. SRG accomplishes immunization against subliminal channel ***, we discuss the application strategies of SRG for symmetric and public-key encryption.

关键词： kleptographic attacks subliminal channel blockchain immunization randomized algorithm

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Goal-Oriented Control Systems(GOCS):From HOW to WHAT

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 816-819页

作者： Wen-Hua chen the Department of Aeronautical and Automotive Engineering Loughborough UniversityLeicestershireLE113TUU.K.

Brief:New control theory is required to underpin safe design and deployment of future highly automated systems to deal with uncertain environments and complicated tasks,enabled by AI and other advanced ***-Oriented Control Systems offer potential to transform the control system design from currently instructing a control system how to perform a task to specifying what is to be achieved.

关键词： automated instru system

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From ore to MOF: A case of MIL-100(Fe) production from iron ore concentrates

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Progress in Natural Science:Materials International 2024年第01期34卷 66-73页

作者： Miao Chang Chiyao Tang Chong-chen Wang chen Zhao Beijing Key Laboratory of Functional Materials for Building Structure and Environment Remediation School of Environment and Energy Engineering Beijing University of Civil Engineering and Architecture

Within this work, iron ore concentrates instead of elemental iron Fe0and iron salts like Fe（NO3）3and FeCl3were selected as iron source to prepare MIL-100（Fe）(labeled as MIL-100（Fe）-ore). The corresponding synthesis cost is reduced to half of the MIL-100（Fe） produced from elemental iron and iron salts. As well, the unreacted iron ore concentrates can be easily separated from the as-prepared MIL-100（Fe）-ore by magnetic to facilitate the purification process, free of the strong acids to wash the residual iron. The as-obtained MIL-100（Fe）-ore with Langmuir surface area up to 2281.6 m2g-1displayed long-term chemical stability. Furthermore, the sorption capacity of MIL-100（Fe）-ore towards malachite green（MG） is up to 522.3 mg g-1at 25℃ and initial pH = 3.2, higher than that of MIL-100（Fe） yielded by conventional hydrothermal process. Finally, the production cost and life cycle assessment of MIL-100（Fe）-ore were compared with other traditional production procedures. The results revealed that our work greatly reduced the synthesis cost and enhanced the environmental sustainability.

关键词： Metal-organic framework Iron ore concentrates Adsorption Life cycle assessment

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The evolutionary trajectory of the rural settlements in Southern Jiangsu in the past 20 years:From the perspective of urbanization and land use

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Journal of Geographical Sciences 2024年第8期34卷 1615-1635页

作者： chen Feiyu chen cheng Key Laboratory of Watershed Geographic Sciences Nanjing Institute of Geography and LimnologyCASNanjing 210008China Nanjing College University of Chinese Academy of SciencesNanjing 211135China

For a long time,due to lack of accurate data covering large areas,it is difficult to capture the continuous spatial evolutionary trajectory of rural settlements shaped by rapid urbanization and rural land use *** fill this gap,based on theoretical analysis this paper systemically detected the changing characteristics of scale,spatial morphology,distribution,and land use pattern of rural settlements in Southern Jiangsu in the past 20 years depending on the data of land resource survey in 2009 and *** study suggests that the total area and per capita size of rural settlements declined by 30%and 2%respectively as a result of rural land consolidation and the influx of enormous immigrants from underdeveloped *** spatial density and average shape index dropped by 14%and 44%respectively in the recent decade,indicating an evident trend of decentralization in spatial distribution,and regularization in the spatial ***,residential land within rural settlements decreased by 33%over the past decade while the land for industry and commercial service steadily increased,demonstrating that the function for manufacturing and diversified services had been *** the emerging issue of the aging population and new business opportunities in rural Southern Jiangsu,rural settlements regeneration might be the focus offutureresearch.

关键词： rural settlements spatial morphology land use Southern Jiangsu

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Siliceous mesocellular foam supported Cu catalysts for promoting non-thermal plasma activated CO_(2) hydrogenation toward methanol synthesis

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Frontiers of Chemical Science and Engineering 2024年第7期18卷 55-65页

作者： Yi chen Shaowei chen Yan Shao Cui Quan Ningbo Gao Xiaolei Fan Huanhao chen State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringNanjing Tech UniversityNanjing 211816China School of Environmental Science and Engineering Nanjing Tech UniversityNanjing 211816China School of Energy and Power Engineering Xi’an Jiaotong UniversityXi’an 710049China Department of Chemical Engineering School of EngineeringThe University of ManchesterManchester M139PLUK Nottingham Ningbo China Beacons of Excellence Research and Innovation Institute University of Nottingham Ningbo ChinaNingbo 315048China Institute of Wenzhou Zhejiang UniversityWenzhou 325006China

Electrified non-thermal plasma (NTP) catalytic hydrogenation is the promising alternative to the thermal counterparts, being able to be operated under mild conditions and compatible with green electricity/hydrogen. Rational design of the catalysts for such NTP-catalytic systems is one of the keys to improve the process efficiency. Here, we present the development of siliceous mesocellular foam (MCF) supported Cu catalysts for NTP-catalytic CO_(2) hydrogenation to methanol. The findings show that the pristine MCF support with high specific surface area and large mesopore of 784 m2·g−1 and ~8.5 nm could promote the plasma discharging and the diffusion of species through its framework, outperforming other control porous materials (viz., silicalite-1, SiO_(2), and SBA-15). Compared to the NTP system employing the bare MCF, the inclusion of Cu and Zn in MCF (i.e., Cu1Zn1/MCF) promoted the methanol formation of the NTP-catalytic system with a higher space-time yield of methanol at ~275 μmol·g_(cat)^(−1)·h^(−1) and a lower energy consumption of 26.4 kJ^(−1)·mmol_(CH_(3)OH)^(-1) (conversely, ~225 μmol·g_(cat)^(−1)·h^(−1) and ~71 kJ^(−1)·mmol_(CH_(3)OH)^(-1), respectively, for the bare MCF system at 10.1 kV). The findings suggest that inclusion of active metal sites (especially Zn species) could stabilize the CO_(2)/CO-related intermediates to facilitate the surface reaction toward methanol formation.

关键词： non-thermal plasma(NTP)catalysis Cu catalyst CO_(2)hydrogenation methanol siliceous mesocellular foam(MCF)

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