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Communications in Theoretical Physics 2005年第1期43卷 187-192页

作者： ZOUWei-Dong liuzu—li WUMing-Hu YAOKai-Lun DepartmentofPhysics HuazhongUniversityofScienceandTechnologyWuhan430074 China／／DepartmentofPhysics XianningTeachersCollegeXianning437005China DepartmentofPhysics HuazhongUniversityofScienceandTechnologyWuhan430074China DepartmentofPhysics XianningTeachersCollegeXianning437005China

Using an accurate density-function method, we explore the coexistence of the magnetism and conductivity in bis(ethylenediselena)-tetrathiafulvalene (BEST) with the paramagnetic hexacyanoferrate(Ⅲ) [Fe(CN)6]3-or the photochromic nitroprusside anion [Fe(CN)5NO]2-. The total and partial densities of states, and the atomic spin magnetic moments are calculated and discussed. It is found that the up- and down-spin total densities of states (DOS)are continuous in the vicinity of the Fermi level, there is overlap between the HOMO and LUMO in the up-spin subbands and the down-spin subbands, which reveals that these types of compounds have conductive properties. From the total and partial densities of states and atomic spin magnetic moments, it is shown that the spin magnetic moments of (BEST)4[Fe(CN)6] is mainly assembled at the iron atom and the cyanogen radical, and the spontaneous magnetic moments for (BEST)2[Fe(CN)5NO] come from iron atom, cyanogen and nitric oxide radical. To our best knowledge, it is the first theoretical study on the coexistence of the magnetism and conductivity of these compounds.

关键词： BEST DOS CN

Strong Ferromagnetic Coupling of {[Cu（Hpht）（N3）]·H2O}n with Simultaneous End-on Azido and Carboxylato Bridges： a First Principle Study

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Communications in Theoretical Physics 2005年第2期43卷 349-352页

作者： YAOKai-Lun ZUFeng-Xia liuzu-li ZOUWei-Dong DepartmentofPhysicsandStateKeyLabofLaserTechnology HuazhongUniversityofScienceandTechnologyWuhan430074China DepartmentofPhysicsandStateKeyLabofLaserTechnology HuazhongUniversityofScienceandTechnologyWuhan430074China／／InternationalCenterofMaterialsPhysicsTheChineseAcademyofSciencesShenyang110015 China

The compound {[Cu(Hpht)(N3)].H2O}n (Hpht = hydrogen phthalate) is formed by chains of copper atoms bridged simultaneously by syn-syn carboxylato and end-on azido bridges. Taking into account the large Cu-O(1)-C(7)bond angle of the single carboxylato bridge (131°), or the large Cu-N(11)-Cu bond angle of the azido bridge (111.9°),a moderately intrachain antiferromagnetic behavior should be expected for the compound. This paper is devoted to examining the apparently anomalous intrachain ferromagnetic behavior of {[Cu(Hpht)(Ns)].H2 O}n, using first principles within the fullpotential linearized augmented plane wave (FP-LAPW) method. The total energy, the density of states (DOS), and the spin distributions are obtained. The atomic spin distribution has been analyzed as resulting from the interplay of electron delocalization and spin polarization. The DOS reveals a surprisingly strong exchange interaction between the d type orbitals of the copper and the πr molecular orbitals of the two ligands.

关键词：铁磁耦合自旋偏振超交换作用量子效应半导体

ab initio Study of Electronic Structure and Magnetic Properties of a Novel N ＊Two-Dimensional Copper（II）-Radical Complex [Cu（NTTmPy）2（N3）2]n

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Communications in Theoretical Physics 2004年第1期41卷 119-122页

作者： YAOKai-Lun WANGli-Qiang liuzu-li ZOUWei-Dong LUOShi-Jun ZUFeng-Xia ZHUlin DepaxtmentofPhysicsandStateKeyLabofLaserTechnology HuazhongUniversityofScienceandTechnologyWuhan430074ChinaInternationalCenterforMaterialsPhysicstheChineseAcademyofSciencesShenyang110015China DepartmentofPhysicsandStateKeyLabofLaserTechnology HuazhongUniversityofScienceandTechnologyWuhan430074China

The full-potential linearized augmented plane wave (FPLAPW) method with the generalized gradientapproximations (GGA) is applied to study the compound [Cu(NTTmPy)2(N3)2]n(NITmPy = 2 - (3' - PyridyX) -4, 4, 5, 5 - tetramethylimidazolin - 1 - oxyl - 3 - oxide). The total density of states (DOS) and the partial densityof states (pDOS) are calculated to explain the electronic and the magnetic properties of [Cu(NTTmPy)2(Na)2]n. It isfound that [Cu(NTTmPy)2(N3)2]n is stable in the ferromagnetic state and the magnetic moment of the molecule mainlycomes from the Cu atoms (0.518μB) with partial contribution from N, 0 atoms of nitronyl nitroxide radicals. Thereexist orbital hybridization between 3d orbital of Cu and p orbitals of N(1) (from pyridyl rings of the NITmPy ligands)and N(4) (from azido group) and the weak direct exchange interactions between Cu and 0 atoms of nitronyl *** addition, the bridging carbon atom (C(6)) carries a significant negative spin density (-O.019μB). The sign alternationof the magnetic moment along the pyridyl ring is obtained, which agrees with experiments.

关键词：电子结构有机磁铁铁磁体铜原子碳原子

Semi-automated detection of rangeland runoff and erosion control berms using high-resolution topography data

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International Soil and Water Conservation Research 2024年第1期12卷 217-226页

作者： li li Changjiang River Scientific Research Institute of Changjiang Water Resources Commission Wuhan430010China Research Center on Mountain Torrent&Geologic Disaster Prevention Ministry of Water ResourcesWuhan430010China University of Arizona School of Natural Resources and the EnvironmentTucsonAZ85719USA

An inventory of topographic modifications is essential to addressing their impacts on hydrological and morphological processes in human-altered ***,such inventories are generally *** study presents two workflows for semi-automatic detection of linear earthen runoff and erosion control berms in rangelands using high-resolution topographic *** workflows consist of initial object identification by applying either morphological grayscale reconstruction(MGR)or the Geomorphon(GEO)method,followed by identification refinements through filters based on objects’horizontal and vertical *** sites were selected within the Altar Valley,Arizona,in the southwestern United *** site was used for developing workflows and optimizing filter thresholds,and the other two sites were used to validate *** results showed that:1)The MGR-based workflow methodology could produce final precision and detection rates of up to 92%and 75%,respectively,and take less than 5 s for a 10.1 km^(2) site;2)The workflow based on the MGR method yielded greater identification accuracy than did the GEO workflow;3)Object length,orientation,and eccentricity were important characteristics for identifying earthen berms,and are sensitive to general channel flow direction and berm shape;4)Manual interrogation of topographic data and imagery can significantly improve identification precision *** proposed workflows will be useful for developing inventories of runoff and erosion control structures in support of sustainable rangeland management.

关键词： Earthen berm Rangeland Grayscale morphological reconstruction Geomorphon liDAR

Theoretical Analysis of Cooperative Driving at Idealized Unsignalized Intersections

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Tsinghua Science and Technology 2024年第1期29卷 257-270页

作者： Shen li Jiawei Zhang Zhenwu Chen li li Department of Civil Engineering Tsinghua UniversityBeijing 100084China Department of Automation Tsinghua UniversityBeijing 100084China Shenzhen Urban Transport Planning Center Co. Ltd.Shenzhen 518000China

Cooperative driving is widely viewed as a promising method to better utilize limited road resources and alleviate traffic *** recent years,several cooperative driving approaches for idealized traffic scenarios(i.e.,uniform vehicle arrivals,lengths,and speeds)have been ***,theoretical analyses and comparisons of these approaches are *** this study,we propose a unified group-by-group zipper-style movement model to describe different approaches synthetically and evaluate their *** derive the maximum throughput for cooperative driving plans of idealized unsignalized intersections and discuss how to minimize the delay of *** obtained conclusions shed light on future cooperative driving studies.

关键词： cooperative driving connected and automated vehicles unsignalized intersection

Perturbed low-thrust geostationary orbit transfer guidance via polynomial costate estimation

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Chinese Journal of Aeronautics 2024年第3期37卷 181-193页

作者： Zhao li Hengnian li Fanghua JIANG Junfeng li State Key Laboratory of Astronautic Dynamics Xi’an Satellite Control CenterXi’an 710043China School of Aerospace Engineering Tsinghua UniversityBeijing 100084China

This paper proposes an optimal,robust,and efficient guidance scheme for the perturbed minimum-time low-thrust transfer toward the geostationary *** Earth’s oblateness perturbation and shadow are taken into *** is difficult for a Lyapunov-based or trajectory-tracking guidance method to possess multiple characteristics at the same time,including high guidance optimality,robustness,and onboard computational *** this work,a concise relationship between the minimum-time transfer problem with orbital averaging and its optimal solution is identified,which reveals that the five averaged initial costates that dominate the optimal thrust direction can be approximately determined by only four initial modified equinoctial orbit elements after a coordinate *** on this relationship,the optimal averaged trajectories constituting the training dataset are randomly generated around a nominal averaged *** polynomial regression models are trained on the training dataset and are regarded as the costate *** the transfer,the spacecraft can obtain the real-time approximate optimal thrust direction by combining the costate estimations provided by the estimators with the current state at any ***,all these computations onboard are *** simulation results show that the proposed guidance scheme possesses extremely high guidance optimality,robustness,and onboard computational efficiency.

关键词： Low thrust Orbital transfer Trajectory optimization Guidance Indirect method Orbital averaging Machine learning Geostationary satellites

Effects of mid-passage gap with a variable surface angle on a turbine vane endwall’s aerothermal and film cooling performances

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Chinese Journal of Aeronautics 2024年第6期37卷 20-37页

作者： Zhiyu li Kaiyuan ZHANG Zhigang li Jun li Institute of Turbomachinery Xi’an Jiaotong UniversityXi’an 710049China

The mid-passage gap is an inevitable structure in a vane passage due to turbine vanes being manufactured *** coolant from this gap is able to prevent hot mainstream ingression and provide cooling protection for the endwall.A novel idea of enlarging the endwall’s coverage area and reducing the endwall’s thermal load by applying the mid-passage gap with variable surface angles is carried out in this *** endwall’s aerothermal and film cooling performances under four mid-passage gap modes at three typical mass flow ratio conditions are numerically *** indicate that under the traditional mid-passage mode,the coolant flows into the mainstream with a perpendicular incidence angle and can’t stick to the ***,cooling failure occurs,and the endwall’s thermal load is badly *** film cooling level at the suction-side endwall is improved when applying the mid-passage gap of a 45surface angle due to the secondary vortex being *** addition,when applying the mid-passage gap of a 135surface angle,the horseshoe vortex is pushed away,and the coverage area at the pressure-side endwall is enlarged *** best film cooling performance is achieved when the upstream surface angle is 135and the downstream surface angle is 45due to the adiabatic film cooling effectiveness being increased at both the pressure-and suction-side *** the mass flow ratio is 1.5%,the coverage area is enlarged by 43%,and the area-averaged adiabatic film cooling effectiveness is increased by 37%,when compared with those under the traditional mid-passage mode.

关键词： Film cooling Heat transfer Surface angle Mid-passagegap Turbinevane endwall

Ultrathin organic solvent nanofiltration membrane with polydopamine-HKUST-1 interlayer for organic solvent separation

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Journal of Environmental Sciences 2024年第7期141卷 182-193页

作者： Haike li Xindong li Guozai Ouyang lijinhong Huang Lang li Wenhao li Wanfu Huang Duokun li Ganzhou Key Laboratory of Basin Pollution Simulation and Control Jiangxi University of Science and TechnologyGanzhou 341000China Innovation Center for Water Quality Security Technology at Ganjiang River Basin Jiangxi University of Science and TechnologyGanzhou 341000China School of Architecture and Design Jiangxi University of Science and TechnologyGanzhou 341000China WA School of Mines:Minerals Energy and Chemical EngineeringCurtin UniversityWA 6845Australia School of Materials Science and Engineering Tiangong UniversityTianjin 300387China

Polydopamine(PDA)and metal-organic skeleton HKUST-1 were co-deposited on the base membrane of hexamethylenediamine(HDA)-crosslinked polyetherimide(PEI)ultrafiltration membrane as the interlayer,and high-throughput organic solvent nanofiltration membrane(OSN)was prepared by interfacial polymerization and solvent activation *** polyamide(PA)layer surface roughness from 28.4 nm in PA/PEI to 78.3 nm in PA/PDA-HKUST-10.6/PEI membrane,reduced the thickness of the separation layer from 79 to 14 nm,and significantly improved the hydrophilic,thermal and mechanical *** flux of the PA/PDA-HKUST-10.6/PEI membrane in a 0.1 g/L Congo Red(CR)ethanol solution at 0.6 MPa test pressure reached 21.8 L/(m^(2)·hr)and the rejection of CR was 92.8%.Solvent adsorption test,N,N-dimethylformamide(DMF)immersion experiment,and long-term operation test in ethanol showed that the membranes had high solvent *** solvent flux test demonstrated that,under the test pressure of 0.6 MPa,the flux of different solvents ranked as follows:methanol(56.9 L/(m^(2)·hr))>DMF(39.6 L/(m^(2)·hr))>ethanol(31.2 L/(m^(2)·hr))>IPA(4.5 L/(m^(2)·hr))>N-hexane(1.9 L/(m^(2)·hr)).The ability of the membranes to retain dyes in IPA/water dyes solution was also *** flux of the membrane was 30.4 L/(m^(2)·hr)and the rejection of CR was 91.6%when the IPA concentration reached 50%.This OSN membrane-making strategy is economical,environment-friendly and efficient,and has a great application prospect in organic solvent separation systems.

关键词： Interfacial polymerization Organic solvent nanofiltration Interlayer Metal-organic frameworks Polydopamine

Heralded entanglement between error-protected logical qubits for fault-tolerant distributed quantum computing

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Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 25-33页

作者： Jialun li Zhihao Xie Yachen li Yansen liang Zhenhua li Tao li MIIT Key Laboratory of Semiconductor Microstructure and Quantum Sensing School of PhysicsNanjing University of Science and TechnologyNanjing 210094China National Laboratory of Solid State Microstructures Nanjing UniversityNanjing 210093China

Quantum error correction is essential for achieving reliable quantum information processing tasks,as it can mitigate the detrimental effects of noise by encoding single-qubit information into a larger quantum ***,the generation of distributed entanglement between logical qubits located within two spatially separated nodes presents a significant resource-intensive challenge that has yet to be *** we present a heralded protocol for generating distributed entanglement between two nonlocal error-protected logical qubits.A high-dimensional single photon can evolve physical qubits into a logical qubit that entangles with the photon and then converts logical qubit-photon entanglement into entanglement between two logical qubits,when the photon state is properly tuned and an effective photon-spin interface between single photons and individual spins is ***,the success of the entanglement generation is heralded by the detection of the photon,and the corresponding efficiency can,in principle,approach *** distinguished features make our protocol highly appealing for future large-scale quantum technologies.

关键词： quantum networks distributed entanglement error-protected logical qubits high-dimensional photons

An efficient approach for the equivalent linearization of frame structures with plastic hinges under nonstationary seismic excitations

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Earthquake Engineering and Engineering Vibration 2024年第3期23卷 677-690页

作者： Huang Huan li Yingxiong li Yuyu College of Water Conservancy and Civil Engineering South China Agricultural UniversityGuangzhou 510642China Institute of Smart City and Intelligent Transportation Southwest Jiaotong UniversityChengdu 611756China

An efficient approach is proposed for the equivalent linearization of frame structures with plastic hinges under nonstationary seismic *** concentrated plastic hinges,described by the Bouc-Wen model,are assumed to occur at the two ends of a linear-elastic beam *** auxiliary differential equations governing the plastic rotational displacements and their corresponding hysteretic displacements are replaced with linearized differential ***,the two sets of equations of motion for the original nonlinear system can be reduced to an expanded-order equivalent linearized equation of motion for equivalent linear *** solve the equation of motion for equivalent linear systems,the nonstationary random vibration analysis is carried out based on the explicit time-domain method with high ***,the proposed treatment method for initial values of equivalent parameters is investigated in conjunction with parallel computing technology,which provides a new way of obtaining the equivalent linear systems at different time *** on the explicit time-domain method,the key responses of interest of the converged equivalent linear system can be calculated through dimension reduction analysis with high *** examples indicate that the proposed approach has high computational efficiency,and shows good applicability to weak nonlinear and medium-intensity nonlinear systems.

关键词： nonstationary random vibration plastic hinge equivalent linearization method explicit time-domain method parallel computation