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Science China(Information Sciences) 2025年第1期68卷 306-321页

作者： Cuijuan ZHANG Lianghao JI Shasha YANG Xing GUO Huaqing LI Chongqing key laboratory of Image Cognition Chongqing University of Posts and Telecommunications key laboratory of Intelligent Perception and Computing of Anhui province Anqing Normal University College of Electronic and Information Engineering Southwest University

This study uses event-triggered(ET) and reinforcement learning methods to investigate the optimal consensus control problem for cooperative-competitive multiagent systems. It proposes a novel distributed ET control strategy, which relies on a prioritized experience replay(PER) policy. This strategy not only conserves communication resources but also ensures acceptable system performance. To implement the proposed method, actor-critic(AC) dual-structured neural networks(NNs) are used to approximate the value function and control policy. In the AC NNs, the weight estimates for the NNs are updated at the moment of event triggering, resulting in a nonperiodic weight adjustment pattern. This approach decreases the computational cost in comparison with the traditional ET mechanism. The PER-based ET mechanism makes full use of valid historical data and effectively establishes a balance between system performance and communication resource ***, it does not require the following two conditions in most existing studies:(1) requirement of the system dynamics model to be known, and(2) persistent excitation. In addition, Zeno behavior is excluded from this study. Finally, a simulation is conducted to confirm the validity of the suggested approach.

关键词： multiagent systems event-triggered mechanism prioritized experience replay dual-structured neural networks optimal consensus control

Modulation of the octahedral structure and potential superconductivity of La3Ni2O7 through strain engineering

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Science China(Physics,Mechanics & Astronomy) 2025年

作者： Zihao Huo Zhihui Luo Peng Zhang Aiqin Yang Zhengtao Liu Xiangru Tao Zihan Zhang Shumin Guo Qiwen Jiang Wenxuan Chen Dao-Xin Yao Defang Duan Tian Cui key laboratory of Material simulation Methods & Software of Ministry of Education State Key Laboratory of Superhard Materials College of Physics Jilin University Center for Neutron Science and Technology Guangdong Provincial Key Laboratory of Magnetoelectric Physics and Devices State Key Laboratory of Optoelectronic Materials and Technologies School of Physics Sun Yat-sen University MOE key laboratory for Non-equilibrium Synthesis and Modulation of Condensed Matter Shaanxi Province Key Laboratory of Advanced Functional Materials and Mesoscopic Physics School of Physics Xi'an Jiaotong University Institute of High Pressure Physics School of Physical Science and Technology Ningbo University

The recent transport measurements of La3Ni2O7uncovered a“right-triangle”shape of the superconducting dome in the pressure-temperature （P-T） phase *** by this,we perform theoretical first-principles studies of La3Ni2O7with the pressure ranging from 0 to 100 ***,we reveal a pressure dependence of the Ni-d2zelectron density at the Fermi energy (nE Fz) that highly coincides with such *** this basis,we further explore the electronic structure under uniaxial *** tracking the stress response of nE Fz,we propose that superconductivity can be achieved by applying only～2 GPa of compression along the c *** idea is further exemplified from the perspectives of lattice distortion,band structure,Fermi surface and superconducting phase *** also discuss the possible charge modulation under the stress and provide an insight into the relation between nE Fzand the superconducting Tcin *** study provides new routes to the search of high-Tcsuperconductors in future experiments.

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Changes in soil organic carbon and nitrogen after 26 years of farmland management on the Loess Plateau of China

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Journal of Arid Land 2015年第6期7卷 806-813页

作者： ZHOU Zhengchao ZHANG Xiaoyan GAN Zhuoting Department of Tourism and Environmental Sciences Shaanxi Normal University key laboratory of disaster survey and mechanism simulation of shaanxi province Baoji University of Arts and Sciences

Soil carbon（C） and nitrogen（N） play a crucial role in determining the soil and environmental quality. In this study, we investigated the effects of 26 years（from 1984 to 2010） of farmland management on soil organic carbon（SOC） and soil N in abandoned, wheat（Triticum aestivum L.） non-fertilized, wheat fertilized（mineral fertilizer and organic manure） and alfalfa（Medicago Sativa L.） non-fertilized treatments in a semi-arid region of the Loess Plateau, China. Our results showed that SOC and soil total N contents in the 0–20 cm soil layer increased by 4.29（24.4%） and 1.39 Mg/hm2（100%）, respectively, after the conversion of farmland to alfalfa land. Compared to the wheat non-fertilized treatment, SOC and soil total N contents in the 0–20 cm soil layer increased by 4.64（26.4%） and 1.18 Mg/hm2（85.5%）, respectively, in the wheat fertilized treatment. In addition, we found that the extents of changes in SOC, soil total N and mineral N depended on soil depth were greater in the upper soil layer（0–30 cm） than in the deeper soil layer（30–100 cm） in the alfalfa land or fertilizer-applied wheat land. Fertilizer applied to winter wheat could increase the accumulation rates of SOC and soil total N. SOC concentration had a significant positive correlation with soil total N concentration. Therefore, this study suggested that farmland management, e.g. the conversion of farmland to alfalfa forage land and fertilizer application, could promote the sequestrations of C and N in soils in semi-arid regions.

关键词： soil organic carbon(SOC) soil N fertilizer land use change semi-arid area

Hydrolysis mechanism of carbendazim hydrolase from the strain Microbacterium ***-6F

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Journal of Environmental Sciences 2017年第4期29卷 171-177页

作者： Ji Lei Shaopeng Wei Lijun Ren Shibin Hu Peng Chen key laboratory of disaster survey and mechanism simulation of shaanxi province College of Chemistry and Chemical EngineeringBaoji University of Arts and Sciences College of Resources and Environment College of Life Sciences and College of Plant ProtectionNorthwest A&F University

The carbendazim（MBC） hydrolyzing enzyme gene was cloned and heterologously expressed in Escherichia coli BL21（DE3） from a newly isolated MBC-degrading bacterium strain Microbacterium sp. strain djl-6F. High performance liquid chromatography-mass spectrometry（HPLC-MS）analysis revealed that purified MheI-6F protein catalyzes direct hydrolysis of MBC into2-aminobenzimidazole（2-AB） with a high turnover rate and moderate affinity（Kmof6.69 μmol/L and kcatof 160.88/min） without the need for any cofactors. The optimal catalytic condition of MheI-6F was identified as 45°C, pH 7.0. The enzymatic activity of MheI-6F was found to be diminished by metal ions, and strongly inhibited by sodium dodecyl sulfate（SDS）.Through generating amino acid mutations in MheI-6F, Cys16 and Cys222 were identified as the catalytic groups that are essential for the hydrolysis of MBC. This is the first report on the biodegradation of MBC at the enzymatice level.

关键词： Carbendazim Microbacterium sp.djl-6F Hydrolase MheI-6F

Modeling pedestrian-vehicle interactions at unsignalized mid-block crosswalk under automated vehicle mixed traffic flow conditions: an agent-based approach

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Journal of Traffic and Transportation Engineering(English Edition) 2025年

作者： Haojie Li Binyue Zhao Ziqian Zhang Yingheng Zhang Gang Ren School of Transportation， Southeast University Jiangsu key laboratory of Urban ITS Jiangsu province Collaborative Innovation Center of Modern Urban Traffic Technologies

The introduction of automated vehicles (AVs) is expected to improve the safety and traffic efficiency of the transportation system. However， the impacts of AVs on pedestrian-vehicle interactions (PVIs) remain unclear， especially under the mixed traffic flow condition with AVs and conventional vehicles (CVs). The objective of this paper is to investigate PVIs under AV mixed traffic flow at unsignalized mid-block crosswalk (UMC) where the right of way competition exists and the traffic conditions are more complex. An agent-based simulation model is proposed to evaluate the safety and traffic efficiency under a diverse range of different scenarios. Some agents’ behavioral parameters are calibrated from trajectory and video data collected at two sites in Nanjing. The proposed model is also validated by comparing Post-Encroachment Time (PET) and pedestrian waiting time outputted from simulation with those extracted from empirical data. The simulation results suggest that the introduction of AVs has limited effect on both safety and efficiency levels at UMC under the low AV penetration rate. Compared to the negotiated yielding strategy of AVs， the conservative yielding strategy performs better in terms of pedestrian safety， but worse in improving traffic efficiency. Moreover， the results reveal that pedestrian and vehicle volumes， the proportion of pedestrians familiar with AVs， and the proportion of risk-prone pedestrians could significantly affect the safety and efficiency levels at UMC. Lastly， we provide some practical recommendations for determining treatments for mid-block crosswalks with AV mixed traffic flow to improve pedestrian safety and traffic efficiency.

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Designing Electronic Structures of Multiscale Helical Converters for Tailored Ultrabroad Electromagnetic Absorption

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Nano-Micro Letters 2025年第1期17卷 439-455页

作者： Zhaobo Feng Chongbo Liu Xin Li Guangsheng Luo Naixin Zhai Ruizhe Hu Jing Lin Jinbin Peng Yuhui Peng Renchao Che key laboratory of Jiangxi province for Persistent Pollutants Control and Resources Recycle School of Environmental and Chemical EngineeringNanchang Hangkong UniversityNanchang 330063People’s Republic of China School of Physics and Materials Nanchang UniversityNanchang 330031People’s Republic of China key laboratory of Nondestructive Testing Ministry of EducationNanchang Hangkong UniversityNanchang 330063People’s Republic of China laboratory of Advanced Materials Shanghai Key Lab of Molecular Catalysis and Innovative MaterialsAcademy for Engineering and TechnologyFudan UniversityShanghai 200438People’s Republic of China

Atomic-scale doping strategies and structure design play pivotal roles in tailoring the electronic structure and physicochemical property of electromagnetic wave absorption(EMWA)***,the relationship between configuration and electromagnetic(EM)loss mechanism has remained ***,drawing inspiration from the DNA transcription process,we report the successful synthesis of novel in situ Mn/N co-doped helical carbon nanotubes with ultrabroad EMWA *** calculation and EM simulation confirm that the orbital coupling and spin polarization of the Mn–N4–C configuration,along with cross polarization generated by the helical structure,endow the helical converters with enhanced EM *** a result,HMC-8 demonstrates outstanding EMWA performance,achieving a minimum reflection loss of−63.13 dB at an ultralow thickness of 1.29 *** precise tuning of the graphite domain size,HMC-7 achieves an effective absorption bandwidth(EAB)of 6.08 GHz at 2.02 mm ***,constructing macroscale gradient metamaterials enables an ultrabroadband EAB of 12.16 GHz at a thickness of only 5.00 mm,with the maximum radar cross section reduction value reaching 36.4 dB *** innovative approach not only advances the understanding of metal–nonmetal co-doping but also realizes broadband EMWA,thus contributing to the development of EMWA mechanisms and applications.

关键词： Metal-nonmetal co-doping 3d-2p orbital coupling Spin polarization Helical structure Broadband EM wave absorption

Sediment Trapping from Hyperconcentrated Flow as Affected by Grass Filter Strips

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Pedosphere 2013年第3期23卷 372-375页

作者： ZHOU Zheng-Chao GAN Zhuo-Ting SHANGGUAN Zhou-Ping Department of Tourism and Environmental Sciences Shaanxi Normal University key laboratory of disaster survey and mechanism simulation of shaanxi province Baoji University of Arts and Sciences State key laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water Conservation Chinese Academy of Sciences

To evaluate the effect of vegetative filter strips on sediment trapping, the spatial distribution of deposited sediment, and the size distribution of deposited particles from hyperconcentrated flows, a simulated grass filter strip experiment was conducted with plastic grass using an adjustable slope steel flume. The simulated vegetation cover was 36%, and the inflow sediment concentrations applied were 147, 238, 320, and 429 kg m^(-3). The sediment concentration in the outflow, and the sediment particle size were determined. The results showed that the grass filter strips trapped most of the sediment from inflow at low sediment concentration. The deposition efficiency decreased with increasing sediment concentration, being 55.2% and 15.7% in the 147 and 429 kg m^(-3)sediment treatments, respectively. Most of the deposited sediments were distributed in the upper flume. In addition, the grass filter strips mainly trapped the coarse sediment (particle size>10 μm).

关键词： erosion Loess Plateau sediment particles vegetation cover

Major elements in the Holocene loess-paleosol sequence in the upper reaches of the Weihe River valley,China

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Journal of Arid Land 2016年第2期8卷 197-206页

作者： WAN Honglian HUANG Chunchang PANG Jiangli key laboratory of disaster Monitoring and mechanism simulation of shaanxi province Baoji University of Arts and Sciences Department of Geographical Science and Environmental Engineering Baoji University of Arts and Sciences College of Tourism and Environmental Sciences Shaanxi Normal University

Palaeohydmlogical investigations were carried out in the Guchuan Basin in the upper reaches of the Weihe River valley, China. A set of palaeoflood slackwater deposits （SWDs） was found interbedded in the Holocene Ioess-paleosol sequence at the Guchuanzhen site （GCZ）. These palaeoflood SWDs were studied by field observations and laboratory analyses including concentrations of chemical elements and optically stimulated luminescence （OSL） dating. The results showed that the palaeoflood SWDs were the result of the secondary separations of the surface soil and weathered soil layers during the process of water transport and deposition, and without obvious weathering during soil development. These extraordinary flood events were dated back to 3,200-3,000 a B.P. with the OSL method and checked by archaeological dating of the human remains retrieved from the profile. These extraordinary flood events were therefore considered as regional expression of known climatic events and demonstrated the climatic instability in the Holocene. This result is important for understanding the effects of global climate change on the dynamics of river systems.

关键词： upper reaches of the Weihe River Holocene Ioess-paleosol sequence major elements

Pyrite Geochemistry and S-Hg Isotopes Reveal the Ore Genesis of the Hydrothermal Vein-type Cuiluan Ag-Pb-Zn Deposit in NE China

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Journal of Earth Science 2025年

作者： Lidong Zhang Changzhou Deng Yao Tang Xinran Ni Bizheng Yang Shanshan Liang Weipeng Liu Jishuang Ding Xiaohui Zeng Heilongjiang Institute of Natural Resources survey State key laboratory of Ore Deposit Geochemistry， Institute of Geochemistry， Chinese Academy of Sciences College of Earth and Planetary Sciences， Chengdu University of Technology

The Xing'an-Mongolian orogenic belt is an important Ag-Pb-Zn metallogenic province in China. The study on the genesis of the newly discovered Cuiluan hydrothermal vein-type Ag-Pb-Zn deposit located in the Lesser Xing'an Range， within the eastern of Xing'an-Mongolian orogenic belt， is pivotal in understanding the metallogenic mechanism and regularity of Ag-Pb-Zn deposits in this region. This study utilizes pyrite trace elements and sulfur isotopic geochemistry， and mercury isotope of rocks and ores to constrain the genesis of the Cuiluan deposit. Pyrite geochemical data show that Ag exists in the form of galena inclusions (Ag++(Bi3+， Sb3+) ? Pb2+) in the polymetallic sulfide stage， and independent Ag-bearing minerals （matildite and gustavite） precipitate during the main mineralization stage. The small varied δ34S values （3.24‰ - 4.94‰） of pyrites from four hydrothermal stages are within the range of magmatic S isotopes， indicating that the ore-forming fluid of the Cuiluan deposit mainly originated from the magma. The Δ199Hg values of the ores are close to 0‰， which are consistent with the Δ199Hg values of mantle， further indicating that the ore-forming materials came from the lithospheric mantle. Combined with the regional tectonic evolution， we conclude that the plate subduction of Paleo-oceans in NE China triggered the partial melting of metasomatized mantle. The mantle-derived magma rose along the deep fractures and evolved ore-forming fluids， and finally caused the formation of Cuiluan quartz vein-type Ag-Pb-Zn deposit in the shallow crust. Accompany with previous documents， we infer that the fractures in the large-scale “Granite Sea” in the Lesser Xing'an Range may have significant potential for vein-type Ag-Pb-Zn exploration.

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Affine Power Flow Multi-scenario Uncertainty Analysis Method for Power System

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Dianwang Jishu/Power System Technology 2025年第1期49卷 252-262页

作者： Chen, Feixiong Wu, Hongbin Shao, Zhenguo Li, Yimin Zhang, He Su, Weiqi key laboratory of Energy Digitalization Fujian Province University Fuzhou University Fujian Province Fuzhou 350108 China Quanzhou Power Supply Company of State Grid Fujian Power Co. Ltd. Fujian Province Quanzhou 362000 China

The power flow solution calculated by the existing affine power flow method can only reflect the power flow distribution of the system in a certain range of the source load power, which is difficult to meet the online calculation requirements of multi-scenario uncertainty analysis. To solve these problems, an affine power flow multi-scenario uncertainty analysis method is proposed in this paper. Various holomorphic embedding variables with different physical meanings are used to scale the central values and partial deviation coefficients of the affine injection power. In this way, the interval variation of uncertain injection power is tracked and described, and the analytical dimension of the affine power flow is expanded from one dimension to multiple dimensions. The calculation of affine power flow is divided into two parts: analytic expression solving and online calculation. The multivariate power series coefficients of affine status variables are solved recursively, and the analytical expression for affine power flow is obtained. The online calculation of affine power flow in specific scenarios is realized by substituting the target value of embedded variables. The simulation results verify the advantages of the proposed method in convergence, conservatism and multi-scenario analysis efficiency. © 2025 Power System Technology Press. All rights reserved.

关键词： Load flow control