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Engineering nanoparticle structure at synergistic Ru-Na interface for integrated CO2 capture and hydrogenation

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Journal of Energy Chemistry 2025年第1期 779-791页

作者： Hanzi liu Ling Cen Xinlin Xie lei liu Zhao Sun Zhiqiang Sun Hunan Engineering Research Center of Clean and Low-Carbon Energy Technology School of Energy Science and Engineering Central South University

The development of dual functional material for cyclic CO2capture and hydrogenation is of great significance for converting diluted CO2into valuable fuels,but suffers from kinetic limitation and deactivation of adsorbent and ***,we engineered a series of RuNa/γ-Al2O3materials,varying the size of ruthenium from single atoms to clusters/*** coordination environment and structure sensitivity of ruthenium were quantitatively investigated at atomic *** findings reveal that the reduced Ru nanoparticles,approximately 7.1 nm in diameter with a Ru-Ru coordination number of 5.9,exhibit high methane formation activity and selectivity at 340°*** Ru-Na interfacial sites facilitate CO2migration through a deoxygenation pathway,involving carbonate dissociation,carbonyl formation,and ***-situ experiments and theoretical calculations show that stable carbonyl intermediates on metallic Ru nanoparticles facilitate heterolytic C–O scission and C–H bonding,significantly lowering the energy barrier for activating stored CO2.

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基于多目标优化的工作量感知即时软件缺陷预测特征构建方法

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计算机科学 2025年第1期52卷 232-241页

作者：赵晨阳刘磊江贺大连理工大学软件学院辽宁大连116600

即时软件缺陷预测(JIT-SDP)是一种针对代码变更的软件缺陷预测技术,具有细粒度、即时性和可追溯性的优点。工作量感知JIT-SDP进一步考虑代码检查工作量,旨在以有限的工作量识别更多的缺陷变更。尽管目前已有不少工作量感知JIT-SDP,但这... 详细信息

即时软件缺陷预测(JIT-SDP)是一种针对代码变更的软件缺陷预测技术,具有细粒度、即时性和可追溯性的优点。工作量感知JIT-SDP进一步考虑代码检查工作量,旨在以有限的工作量识别更多的缺陷变更。尽管目前已有不少工作量感知JIT-SDP,但这些方法大多只针对分类模型算法进行优化。为提升工作量感知JIT-SDP的性能表现与泛用性,首次从特征工程方面入手,提出了一种工作量感知场景下的进化特征构建方法EEF。首先,EEF方法通过遗传编程树来表示特征,从分类性能与工作量感知性能两个角度出发,通过基于多目标优化的进化特征构建方法来获取新的特征转换方法;之后,通过得到的特征转换方法来构建新的特征集,并基于新的特征集训练与测试分类模型。为了验证EEF方法的有效性,在6个开源项目上,通过3个不同评估方案进行了实验研究,结果证明EEF方法可以提升分类模型在工作量感知场景下的性能,并优于其他特征工程方法,而且在保证特征选取多样性的前提下,基于单一模型的EEF方法同样可以提升其他模型的性能。

关键词：即时缺陷预测工作量感知进化特征构建多目标优化特征工程

An FFT-Based High SNR MWC Back-End Architecture with Analog Low-Pass Filter Compensation

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Chinese Journal of Electronics 2020年第3期29卷 563-573页

作者： liu Sujuan liu lei Beijing University of Technology

We study the impacts of non-ideal filters in Modulated wideband converter(MWC). An analog filter compensating method is presented. The limitations of the conventional back-end of the advanced MWC is analyzed and an improved back-end based on Fast Fourier transform(FFT) is proposed. By setting proper length of the digital signal processed each time, the proposed system increases the recovery Signal-to-noise ratio(SNR)and significantly reduces the computation loads. The compensating operation is accurate to each frequency point and the expanding operation is simplified to a splitting of the frequency points. Numerical simulations demonstrate our proposed system against the ideal MWC with different filters. The results indicate that the recovery SNR of over 70 decibel is achieved with almost only one-tenth the computation complexity of the conventional MWC backend.

关键词： Compressed sensing Modulated wideband converter Fast Fourier transform Non-ideal low-pass filters Compensation

Lagrangian Grassmann manifold （2）

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Frontiers of Mathematics in China 2018年第2期13卷 341-365页

作者： lei liu Department of Mathematics Shandong University Jinan 250100 China

Based on the relationship between symplectic group Sp（2） and （2）, we provide an intuitive explanation （model） of the 3-dimensional Lagrangian Grassmann manifold （2）, the singular cycles of （2）, and the speci... 详细信息

关键词： Lagrangian Grassmann manifold Lagrangian plane geometric representation singular cycle

Chaotic Feature in the Light Curve of 3C 273

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Chinese Journal of Astronomy and Astrophysics 2006年第6期6卷 663-668页

作者： lei liu Institute of Particle Physics Huazhong Normal University Wuhan 430079

Some nonlinear dynamical techniques, including state-space reconstruction and correlation integral, are used to analyze the light curve of 3C 273. The result is compared with a chaotic model. The similarities between ... 详细信息

关键词： galaxies active - galaxies individual 3C 273

Lie Triple Derivations on von Neumann Algebras

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Chinese Annals of Mathematics,Series B 2018年第5期39卷 817-828页

作者： lei liu School of Mathematics and Statistics Xidian University School of Mathematical Sciences Fudan University

Let A be a von Neumann algebra with no central abelian projections. It is proved that if an additive map δ :A → A satisfies δ([[a, b], c]) = [[δ(a), b], c] + [[a, δ(b)], c] +[[a, b], δ(c)] for any a, b, c∈ A with ab = 0(resp. ab = P, where P is a fixed nontrivial projection in A), then there exist an additive derivation d from A into itself and an additive map f :A → ZA vanishing at every second commutator [[a, b], c] with ab = 0(*** = P) such that δ(a) = d(a) + f(a) for any a∈ A.

关键词： Derivations Lie triple derivations von Neumann algebras

High-throughput computational screening of Cu-MOFs with open metal sites for efficient C_2H_2/C_2H_4 separation

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Green Energy & Environment 2020年第3期5卷 333-340页

作者： lei liu lei Wang Dahuan liu Qingyuan Yang Chongli Zhong State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029China Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China State Key Laboratory of Separation Membranes and Membrane Processes TianGong UniversityTianjin 300387China

Cost effective separation of acetylene(C_2H_2)and ethylene(C_2H_4)is of key importance to obtain essential chemical raw materials for polymer *** to the low compression limit of C_2H_2,there is an urgent demand to develop suitable materials for efficiently separating the two gases under ambient *** this paper,we provided a high-throughput screening strategy to study porous metal-organic frameworks(MOFs)containing open metal sites(OMS)for C_2H_2/C_2H_4 separation,followed by a rational design of novel MOFs in-silico.A set of accurate force fields was established from ab initio calculations to describe the critical role of OMS towards guest *** a large-scale computational screening of 916 experimental Cu-paddlewheel-based MOFs,three materials were identified with excellent separation *** structure-performance relationships revealed that the optimal materials should have the largest cavity diameter around 5-10?and pore volume in-between 0.3-1.0 cm^3 g^(-1).Based on the systematic screening study result,three novel MOFs were further designed with the incorporation of fluorine functional *** results showed that Cu-OMS and the-F group on the aromatic rings close to Cu sites could generate a synergistic effect on the preferential adsorption of C_2H_2 over C_2H_4,leading to a remarkable improvement of C_2H_2 separation performance of the *** findings could provide insight for future experimental design and synthesis of high-performance nanostructured materials for C_2H_2/C_2H_4 separation.

关键词： Acetylene and ethylene Metal-organic frameworks Open metal sites Large-scale computation Materials design

泥质粉砂岩粒度分形特征及其与抗剪强度参数的关系

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河南理工大学学报（自然科学版） 2025年第1期44卷 37-45页

作者：李东杜俊刘磊熊治茗昆明理工大学国土资源工程学院云南昆明650093 昆明学院建筑工程学院云南昆明650214 昆明理工大学公共安全与应急管理学院云南昆明650093

泥质粉砂岩堆石料剪切力学特性与分形特征的相关性研究对排土场边坡稳定性具有重要意义。目的为探究不同粗粒含量下泥质粉砂岩堆石料力学响应特性,并探讨其与分形维数的相关性,方法以不同粗粒含量堆石料为研究对象,开展室内直剪试验,分... 详细信息

泥质粉砂岩堆石料剪切力学特性与分形特征的相关性研究对排土场边坡稳定性具有重要意义。目的为探究不同粗粒含量下泥质粉砂岩堆石料力学响应特性,并探讨其与分形维数的相关性,方法以不同粗粒含量堆石料为研究对象,开展室内直剪试验,分析土体在不同粗粒含量下抗剪强度参数与分形维数之间的相关性并揭示其力学响应机理。结果结果表明:泥质粉砂岩堆石料抗剪强度受粗粒含量影响显著,相同垂直压力下堆石料抗剪强度随粗粒含量增加而增大,以垂直压力2000 kPa为例,粗粒含量由20%增加到80%,其抗剪强度增幅19.66%。抗剪强度参数与粗粒含量密切相关,随着粗粒含量增加,黏聚力减小,内摩擦角增大,内摩擦角受粗粒含量影响更显著。分形维数随着粗粒含量增大呈减小趋势,它可表征堆石料颗粒级配组成及不均匀特征,当分形维数为1.887~2.631时,表明堆石料为级配良好的土体。分形维数与粗粒含量和抗剪强度参数之间存在相关性,分形维数与黏聚力呈正相关,与粗粒含量和内摩擦角均呈负相关。结论粗粒含量对泥质粉砂岩堆石料的力学性质影响显著,同时分形维数可作为评价堆石料级配和不均匀特征的重要参数。

关键词：泥质粉砂岩粗粒含量直剪试验剪切特性粒度分形

Observer-Based Adaptive Fuzzy Tracking Control Using Integral Barrier Lyapunov Functionals for A Nonlinear System With Full State Constraints

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IEEE/CAA Journal of Automatica Sinica 2021年第3期8卷 617-627页

作者： Wei Zhao Yanjun liu lei liu School of Electrical Engineering Liaoning University of TechnologyJinzhou 121001China College of Science Liaoning University of TechnologyJinzhou 121001China

A new fuzzy adaptive control method is proposed for a class of strict feedback nonlinear systems with immeasurable states and full *** fuzzy logic system is used to design the approximator,which deals with uncertain and continuous functions in the process of backstepping *** use of an integral barrier Lyapunov function not only ensures that all states are within the bounds of the constraint,but also mixes the states and errors to directly constrain the state,reducing the conservativeness of the constraint satisfaction *** that the states in most nonlinear systems are immeasurable,a fuzzy adaptive states observer is constructed to estimate the unknown *** with adaptive backstepping technique,an adaptive fuzzy output feedback control method is *** proposed control method ensures that all signals in the closed-loop system are bounded,and that the tracking error converges to a bounded tight set without violating the full state *** simulation results prove the effectiveness of the proposed control scheme.

关键词： Adaptive control backstepping design integral barrier Lyapunov function(iBLF) states observer