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Nano Research 2025年第1期18卷 195-207页

作者： Chun Zhu Yifei Yang Yike Jing Zhen zeng Xuesong Yi Wei Sun Fei Yang Key Laboratory of Agro-Forestry Environmental Processes and Ecological Regulation of Hainan Province School of Environmental Science and EngineeringHainan UniversityHaikou 570228China

Electrochemical nitrate reduction reaction(NO3RR)to ammonia is a promising approach to address excess Ncontamination in aqueous environment but suffers from a limited ammonia yield and selectivity due to the low concentration and sluggish *** work reports a three-dimensional porous electrode with binary Co_(2)Cu_(1)hydroxy phosphate embedded into the surface of Ni_(3)Co_(1)oxy/hydroxides(CoCu-PH@NiCo/Ni,“PH”means phosphate-hydroxide),which delivers a yield of 4.13 mg·h^(-1)·cm^(-2)with a high Faraday efficiency of 92.6%under a low nitrate concentration of 40 mM and provide an impressive *** embedded structure of the as-prepared catalyst exhibits unique metal coordination ligands and valence states different from the unitary *** electrochemical in situ infrared spectra and theoretical calculations revealed that the Co sites with the ability to dissociate water molecular to form adsorbed OH*can effectively provide the required protons for the deoxygenation and hydrogenation steps during NO3-conversion,thereby,effectively reducing the energy barrier of the key transition states in the NO3RR process to improve the intrinsic *** demonstrate that the rational design of binary components with the appropriate ability to activate water molecules as well as the threedimensional porous skeletal structure are expected to promote effectively the low-concentration nitrates conversion to ammonia.

关键词： nitrate reduction hydroxy phosphate surface embedded water dissociation active hydroxy adsorbed

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无线供电MEC系统的计算能效最大化策略

郑州大学学报（工学版） 2025年第1期46卷 133-142页

作者：李陶深巩健曾续玲吕品南宁学院信息工程学院广西南宁530299 广西大学计算机与电子信息学院广西南宁530004

为了解决无线供电移动边缘计算(MEC)系统的计算能效优化问题,提出一种基于非正交多址接入的无线供电MEC系统的资源分配策略。该策略将非线性能量收集模型应用到移动设备上,通过联合优化MEC服务器和移动设备的计算频率、执行时间、基站... 详细信息

为了解决无线供电移动边缘计算(MEC)系统的计算能效优化问题,提出一种基于非正交多址接入的无线供电MEC系统的资源分配策略。该策略将非线性能量收集模型应用到移动设备上,通过联合优化MEC服务器和移动设备的计算频率、执行时间、基站发射功率、设备发射功率、卸载时间和能量收集时间,比较充分地利用移动设备和MEC服务器的可用计算资源,提高设备的吞吐量和计算位数,进而最大限度地提升系统计算能效。将该联合优化问题转化为非凸分式规划问题,设计一种基于Dinkelbach的迭代算法来获得最优的资源分配方案。仿真实验表明:该资源分配策略所获得的系统计算能效更高,具有更好的性能增益。

关键词：无线供电移动边缘计算系统非正交多址接入计算能效能量收集资源分配计算卸载

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Soil microbial attributes along a chronosequence of Scots pine(Pinus sylvestris var. mongolica) plantations in northern China

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Pedosphere 2020年第4期30卷 433-442页

作者： Xiaodong YAO Wenjing zeng Hui zeng Wei WANG Department of Ecology College of Urban and Environment Sciences and Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking UniversityBeijing 100871(China) School of Urban Planning and Design Peking University Shenzhen University TownShenzhen 518055(China)

Soil microorganisms play a key role in soil organic matter dynamics, nutrient cycling, and soil fertility maintenance in forest ecosystems, and they are influenced by stand age and soil depth. However, few studies have simultaneously considered these two factors. In this study, we measured soil microbial biomass carbon (SMBC), soil microbial biomass nitrogen (SMBN), soil basal respiration (SBR) rate, and potential extracellular enzyme activity (EEA) in soil to a depth of 60 cm under 10-, 30-, and 40-year-old Scots pine (Pinus sylvestris var. mongolica) stands (Y10, Y30, and Y40, respectively) in plantations in northern China in 2011. Soil water content (SWC), soil pH, soil organic carbon (SOC), and soil total nitrogen (STN) were also measured to explore their effects on soil microbial indices across different stand ages and soil depths. Our results showed that SMBC, SMBN, and the SBR rate were generally higher for the Y30 stand than for the Y10 and Y40 stands. Potential EEA, except forα-glucosidase, decreased significantly with increasing stand age. Soil organic carbon,STN, SWC, and soil pH explained 67%of the variation in soil microbial attributes among the three stand ages. For the same stand age, soil microbial biomass and the SBR rate decreased with soil depth. Lower microbial biomass, lower SBR rate, and lower EEA for the mature Y40 stand indicate lower substrate availability for soil microorganisms, lower soil quality, and lower microbial adaptability to the environment. Our results suggest that changes in soil quality with stand age should be considered when determining the optimum rotation length of plantations and the best management practices for afforestation programs.

关键词： soil microbial metabolism quotient(gCO2) soil basal respiration soil depth soil microbial biomass soil organic matter dynamics soil potential extracellular enzyme activity stand age

Optimal reduction of anthropogenic emissions for air pollution control and the retrieval of emission source from observed pollutantsⅢ:Emission source inversion using a double correction iterative method

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Science China Earth Sciences 2022年第3期65卷 553-555页

作者： Qingcun zeng Lin WU Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China

Using the incomplete adjoint operator method in part I of this series of papers,the total emission source S can be retrieved from the pollutant concentrationsρob obtained from the air pollution monitoring *** paper studies the problem of retrieving anthropogenic emission sources from *** that the natural source Sn is known,and as the internal source Sc due to chemical reactions is a function of pollutant concentrations,if the chemical reaction equations are complete and the parameters are accurate,Sc can be calculated directly fromρob,and then Sa can be obtained from ***,if the chemical reaction parameters(denoted asγ)are insufficiently accurate,bothγand Sc should be *** article proposes a"double correction iterative method"to retrieve Sc and correctγand proves that this iterative method converges.

关键词： Air pollution Anthropogenic emission source Source due to chemical reaction Source retrieval Incomplete adjoint operator Double correction iterative method

On the matrix feedback shift register synthesis for matrix sequences

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Science China(Information Sciences) 2016年第3期59卷 87-96页

作者： Liping WANG Guang zeng Institute of Information Engineering Chinese Academy of Sciences Zhengzhou Information Science and Technology Institute

In this paper, a generalization of the linear feedback shift register synthesis problem is presented for synthesizing minimum-length matrix feedback shift registers(MFSRs for short) to generate prescribed matrix sequences and so a new complexity measure, that is, matrix complexity, is introduced. This problem is closely related to the minimal partial realization in linear systems and so can be solved through any minimal partial realization algorithm. All minimum-length MFSRs capable of generating a given matrix sequence with finite length are characterized and a necessary and sufficient condition for the uniqueness issue is obtained. Furthermore, the asymptotic behavior of the matrix complexity profile of random vector sequences is determined.

关键词： Berlekamp-Massey algorithm minimal partial realization multisequences σ-LFSR

Multi-dimensional Modeling of the Application of Catalytic Combustion to Homogeneous Charge Compression Ignition Engine

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Journal of Thermal Science 2006年第4期15卷 371-376页

作者： Wen zeng MaoZhao Xie Department of Power Engineering Dalian University of Technology Dalian 116024 China

The detailed surface reaction mechanism of methane on rhodium catalyst was analyzed. Comparisons between numerical simulation and experiments showed a basic agreement. The combustion process of homogeneous charge compression ignition （HCCI） engine whose piston surface has been coated with catalyst （rhodium and platinum） was numerically investigated. A multi-dimensional model with detailed chemical kinetics was built. The effects of catalytic combustion on the ignition timing, the temperature and CO concentration fields, and HC, CO and NOx emissions of the HCCI engine were discussed. The results showed the ignition timing of the HCCI engine was advanced and the emissions of HC and CO were decreased by the catalysis.

关键词： catalytic combustion homogeneous charge compression ignition(HCCI) CFD methane detailed chemical kinetics.

Redesign of the gStore system

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Frontiers of Computer Science 2018年第4期12卷 623-641页

作者： Li zeng Lei ZOU School of Electronics Engineering and Computer Science Peking University Beijing 100871 China Beijing Institute of Big Data Research Beijing 100871 China

gStore is an open-source native Resource Description Framework （RDF） triple store that answers SPARQL queries by subgraph matching over RDF graphs. However, there are some deficiencies in the original system design, such as answering simple queries （including one-triple pattern queries）. To improve the efficiency of the system, we reconsider the system design in this paper. Specifically, we propose a new query plan generation module that generates different query plans according to the structures of query graphs. Furthermore, we re-design our vertex encoding strategy to achieve more pruning power and a new multi-join algorithm to speed up the subgraph matching process. Extensive experiments on synthetic and real RDF datasets show that our method outperforms the state-of-the-art algorithms significantly.

关键词： graph database subgraph matching RDF management SPARQL query

ASSET-LIABILITY MANAGEMENT UNDER BENCHMARK AND MEAN-VARIANCE CRITERIA IN A JUMP DIFFUSION MARKET

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Journal of Systems Science & Complexity 2011年第2期24卷 317-327页

作者： Yan zeng Zhongfei LI School of Mathematics and Computational Science Sun Yat-sen University Guangzhou 510275 China. Lingnan College & Management School Sun Yat-sen University Guangzhou 510275 China.

This paper investigates continuous-time asset-liability management under benchmark and mean-variance criteria in a jump diffusion market. Specifically, the authors consider one risk-free asset, one risky asset and one liability, where the risky asset＇s price is governed by an exponential Levy process, the liability evolves according to a Levy process, and there exists a correlation between the risky asset and the liability. Two models are established. One is the benchmark model and the other is the mean-variance model. The benchmark model is solved by employing the stochastic dynamic programming and its results are extended to the mean-variance model by adopting the duality theory. Closed-form solutions of the two models are derived.

关键词： Asset-liability management benchmark and mean-variance models duality theory jumpdiffusion market Hamilton-Jacobi-Bellman equation.

Single Image Dehazing Based on Combining Dark Channel Prior and Scene Radiance Constraint

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Chinese Journal of Electronics 2016年第6期25卷 1114-1120页

作者： zeng Liang DAI Yongzhen College of Computer National University of Defense Technology

Images captured in foggy or hazy weather conditions often suffer from poor visibility. The dark channel prior method has well solved the single image dehazing problem in nature, but it is invalid when the scene objects are inherently similar to the atmospheric light and no shadow is cast on them. We propose an efficient regularization method by adding a scene radiance constraint and combing the dark channel prior to remove hazes from a single input image. The experiments show that this improved algorithm can deal with various levels of foggy weather conditions, as well as greatly enhance the image's visibility and details. In addition, the recovered haze-free image has little or no halo artifacts.

关键词： Image dehazing Scene radiance constraint Dark channel prior Visibility enhancement Detail augment

Interrogating imaginary optical force by the complex Maxwell stress tensor theorem

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Light(Science & Applications) 2023年第1期12卷 12-14页

作者： Jinwei zeng Jian Wang Wuhan National Laboratory for Optoelectronics and School of Optical and Electronic Information Huazhong University of Science and TechnologyWuhan 430074 HubeiChina Optics Valley Laboratory Wuhan 430074 HubeiChina

The complex Maxwell stress tensor theorem has been developed to relate the imaginary optical force,reactive strength of canonical momentum and total optical force of a nanoparticle,which is essential to perfect optica... 详细信息

关键词： imaginary tensor theorem