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Defence Technology（防务技术） 2024年第1期31卷 288-294页

作者： er-hai An Xiao-xia li Cun-juan Yu Ying-xin Tan Zi-jun Fan Qing-xia li Peng Deng Xiong Cao School of Environment and Safety Engineering North University of ChinaTaiyuan030051PR China College of Safety and Emergency Management Engineering Taiyuan University of Science and TechnologyTaiyuan030024PR China

Fe/N-based biomass porous carbon composite(Fe/N-p Carbon) was prepared by a facile high-temperature carbonization method from biomass,and the effect of Fe/N-p Carbon on the thermal decomposition of energetic molecular perovskite-based material DAP-4 was *** porous carbonaceous materials was considered as the micro/nano support layers for in situ deposition of Fe/N ***/Np Carbon was prepared simply by the high-temperature carbonization *** was found that it showed the inherent catalysis properties for thermal decomposition of *** heat release of DAP-4/Fe/N-p Carbon by DSC curves tested had increased slightly,compared from DAP-4/Fe/N-p *** decomposition temperature peak of DAP-4 at the presence of Fe/N-p Carbon had reduced by 79°C from384.4°C(pure DAP-4) to 305.4°C(DAP-4/Fe/N-p Carbon-3).The apparent activation energy of DAP-4thermal decomposition also had decreased by 29.1 J/*** possible catalytic decomposition mechanism of DAP-4 with Fe/N-p Carbon was proposed.

关键词： Biomass materials Porous carbon DAP-4 Thermal decomposition Facile method

Cerium oxide inclusion nucleation mechanism based on classical nucleation theory and two-step nucleation

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Journal of Rare Earths 2024年第4期42卷 793-802页

作者： Yutang li Jun wang linzhu wang Chaoyi Chen Shufeng Yang Junqi li Xiang li School of Materials and Metallurgy Guizhou UniversityGuiyang550025China State Key Laboratory of Public Big Data Guizhou UniversityGuiyang550025China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China Department of Materials&Metallurgy Engineering Guizhou Institute of TechnologyGuiyang550003China

It is challenging to assess the mechanism responsible for the nucleation of inclusions in metals at high *** present work therefore systematically investigates the nucleation of cerium oxide inclusions according to classical nucleation theory and a two-step nucleation *** nucleation rates and nucleation radii of these inclusions are obtained,and the results demonstrate a considerable difference between theoretical and experimental *** the basis of a two-step nucleation mechanism,(CeO_(2))_(n) and(Ce_(2)O_(3))_(n)(n=1-6)clusters were constructed and the thermodynamic properties of both these clusters and of cerium oxide nanoparticles were *** addition,the entropies and heat capacity changes of cerium oxides were determined using first principles calculations and are found to be consistent with literature *** present data indicate that the cerium oxide inclusion nucleation pathway can be summarized as[Ce]+[O]→(CeO_(2))n/(Ce_(2)O_(3))_(n)→(Ce_(2)O_(3))_(n)→(Ce_(2)O_(3))_(2)→core(Ce_(2)O_(3)crystal)-shell((Ce_(2)O_(3))_(2) cluster)nanoparticles→(Ce_(2)O_(3))bulk.

关键词： Cerium oxide inclusion Classical nucleation theory Two-step nucleation mechanism First principles Rare earths

Evolution mechanism and quantitative characterization of initial micro-cracks in marble under triaxial compression

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第7期25卷 586-595页

作者： Zhiliang wang Songyu li Jianguo wang Ao li Weixiang wang Chenchen FENG Jingjing FU School of Civil Engineering Hefei University of TechnologyHefei230009China School of Mechanics and Civil Engineering China University of Mining and TechnologyXuzhou221116China

The initial micro-cracks affect the evolution characteristics of macroscopic deformation and failure of rock but are often ignored in theoretical calculation,numerical simulation,and mechanical *** this study,we propose a quantitative analysis model to investigate the effects of initial micro-cracks on the evolution of marble deformation and *** relationship between the micro-crack propagation and the marble failure characteristics was comprehensively studied by combining theoretical analysis with a micro-computed tomography(micro-CT)scanning *** found that with the increase of confining pressure,the matrix elastic modulus of the marble first increased and then tended to be stable,while the micro-cracks increased *** sensitivity ranges of the marble sample matrix elastic modulus and micro-cracks to confining pressure were 0–30 MPa and 30–50 MPa,*** porosity and Poisson’s ratio decreased *** increasing proportion of internal micro-cracks led to an increase in the sample *** samples presented mainly shear failure under triaxial compression,and the failure angle decreased linearly with the increase of confining *** convergence direction of cracks decreased *** quantitative analysis model could accurately portray the relationship between the overall macroscopic deformation and the deviatoric stress of the samples at the compaction and the linear elastic stages,thus deepening the understanding of the stress–strain behavior of rocks.

关键词： Marble Initial micro-cracks Triaxial compression Constitutive relationship Crack evolution

erosion-induced recovery CO_(2) sink offset the horizontal soil organic carbon removal at the basin scale

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Science China Earth Sciences 2024年第6期67卷 2019-2033页

作者： lingxia wang Xiaodong NIE Jiaqi li Yaojun liU Hui wang Yazhe li Zhongwu li School of Geographic Science Hunan Normal UniversityChangsha 410081China Institute of Interdisciplinary Studies Hunan Normal University and Hunan Provincial Key Laboratory for Eco-environmental Changes and Carbon Sequestration of the Dongting Lake BasinChangsha 410081China College of Environmental Science and Engineering Hunan University and Key Laboratory of Environmental Biology and Pollution Control(Hunan University)Ministry of EducationChangsha 410082China

To improve soil carbon sequestration capacity,the full soil carbon cycle process needs to be understood and *** is essential to evaluate whether water erosion acts as a net source or sink of atmospheric CO_(2)at the basin scale,which encompasses the entire hydrological *** study introduced an approach that combined a spatially distributed sediment delivery model and biogeochemical model to estimate the lateral and vertical carbon fluxes by water erosion at the basin *** this coupling model to the Dongting Lake Basin,the results showed that the annual average amount of soil erosion during 1980-2020 was 1.33×10^(8)t,displaying a decreasing trend followed by a slight *** 12% of the soil organic carbon displacement was ultimately lost in the riverine systems,and the rest was deposited downhill within the *** average lateral soil organic carbon loss induced by erosion was 8.86×10^(11)g C in 1980 and 1.50×10^(11)g C in 2020,with a decline rate of 83%.A net land sink for atmospheric CO_(2)of 5.54×1011g C a^(-1)occurred during erosion,primarily through sediment burial and dynamic ***,ecological restoration projects and tillage practice policies are still significant in reducing erosion,which could improve the capacity of the carbon sink for recovery beyond the rate of horizontal carbon ***,our model enables the spatial explicit simulation of erosion-induced carbon fluxes using costeffective and easily accessible input data across large spatial scales and long ***,it offers a valuable tool for predicting the interactions between carbon dynamics,land use changes,and future climate.

关键词： Water erosion Sediment transfer Lateral soil carbon loss Land-atmosphere CO_(2) flux Dongting Lake Basin

Effects of operating conditions on iron(hydr)oxides evolution and ciprofloxacin degradation in potassium ferrate-ozone stepwise oxidation system

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Journal of Environmental Sciences 2024年第1期135卷 367-378页

作者： Xiaochen li Yifan wang Ning wang Mei li Maomao Bai Jingtao Xu Hongbo wang School of Municipal and Environmental Engineering Shandong Jianzhu UniversityJinan 250101China Resources and Environment Innovation Institute Shandong Jianzhu UniversityJinan 250101China

In this study,a stepwise oxidation system of potassium ferrate(K_(2)FeO_(4))combined with ozone(O+3)was used to degrade ciprofloxacin(CIP).The effects of pH and pre-oxidation time of K_(2)FeO_(4) on the evolution of K_(2)FeO_(4) reduction products(iron(hydr)oxides)and CIP degradation were *** was found that in addition to its own oxidation capacity,K_(2)FeO_(4) can also influence the treatment effect of CIP by changing the catalyst *** presence of iron(hydr)oxides effectively enhanced the mineralization rate of CIP by catalyzing *** pH value can influence the content and types of the components with catalytic ozonation effect in iron(hydr)*** K_(2)FeO_(4) pre-oxidation stage can produce more iron(hydr)oxides with catalytic components for subsequent ozonation,but the evolution of iron(hydr)oxides components was influenced by O_(3) *** can also avoid the waste of oxidation capacity owing to the oxidation of iron(hydr)oxides by O_(3) and free *** intermediate degradation products were identified by Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR-MS).Besides,the degradation pathways were *** the degradation products of CIP,the product with broken quinolone ring structure only appeared in the stepwise oxidation system.

关键词： Potassium ferrate reduction products Catalytic ozonation Ciprofloxacin Potassium ferrate pre-oxidation time

Constrained docking control for shipborne UAV SideArm recovery

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Chinese Journal of Aeronautics 2024年第5期37卷 39-59页

作者： Zikang SU Zhuolin XING Xuebing li Chuntao li Xinwei wang Honglun wang College of Automation Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China School of Engineering and Materials Science Queen Mary University of LondonLondon E14NSUK School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China

In this work,we sought to investigate constrained docking control during shipborne SideArm recovery of an Unmanned Aerial Vehicle(UAV)under preassigned safe docking constraints,rough ocean environments,and different initial *** aim was to solve the UAV tracking-lag problem that manifests when attempting to dock with a rapidly moving SideArm and to improve the accuracy and rapidity of ***,together with the formulations of the shipborne SideArm system and environmental airflows,the affine nonlinear dynamics of the hook was established to reduce tracking ***,echo state network approximators with good approximation capacity and low computational consumption were designed to accurately approximate the UAV’s unknown nonlinear *** feedforward compensation provided by these approximators,a nonlinear-mapping-based constrained docking control law was developed for shipborne SideArm recovery of *** approach to controlling the docking trajectory and the forward docking speed of the UAV can achieve rapid and exact docking with a moving SideArm,without violating the preassigned safe docking-constraint *** under different docking scenarios were used to validate the effectiveness and advantages of the proposed docking-control algorithm.

关键词： SideArm recovery Unmanned aerial vehicle Docking control Nonlinear mapping Echo state network

The influence of inter-band rock on rib spalling in longwall panel with large mining height

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International Journal of Mining Science and Technology 2024年第4期34卷 427-442页

作者： Jiachen wang Meng li Zhaohui wang Zheng li Han Zhang Shixiong Song School of Energy and Mining Engineering China University of Mining and Technology-BeijingBeijing 100083China Coal Industry Engineering Research Center of Top-coal Caving Mining Beijing 100083China Faculty of Engineering Hokkaido UniversitySapporo 060-8628Japan

In order to improve rib stability,failure criteria and instability mode of a thick coal seam with inter-band rock layer are analysed in this study.A three-dimensional mechanical model is established for the rib by considering the rock layer.A safety factor is defined foy the rib,and it is observed that the safety factor exhibits a positive correlation with the thickness and strength of the inter-band rock.A calculation method for determining critical parameters of the rock layer is presented to ensure the rib *** is revealed that incomplete propagation of the fracture at the hard rock constitutes a fundamental prerequisite for ensuring the rib *** influence of the position of the inter-band rock in the coal seam on failure mechanism of the rib was thoroughly investigated by developing a series of physical models for the rib at the face *** best position for the inter-band rock in the coal seam is at a height of 1.5 m away from the roof line,which tends to provide a good stability state for the *** different inter-band rock positions,two ways of controlling rib by increasing supports stiffness and flexible grouting reinforcement are proposed.

关键词： Rib spalling Inter-band rock Large mining height limit analysis Physical model experiment Numerical simulation

Functional Optical Fiber Sensors Detecting Imperceptible Physical/Chemical Changes for Smart Batteries

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Nano-Micro Letters 2024年第8期16卷 268-308页

作者： Yiding li li wang Youzhi Song Wenwei wang Cheng lin Xiangming He Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing 100084People’s Republic of China National Engineering Research Center of Electric Vehicles Beijing Institute of Technology(BIT)Beijing 100081People’s Republic of China Shenzhen Automotive Research Institute of BIT(Shenzhen Research Institute of National Engineering Research Center of Electric Vehicles) Shenzhen 518118People’s Republic of China

The battery technology progress has been a contradictory process in which performance improvement and hidden risks *** the battery is still a“black box”,thus requiring a deep understanding of its internal *** battery should“sense its internal physical/chemical conditions”,which puts strict requirements on embedded sensing *** paper summarizes the application of advanced optical fiber sensors in lithium-ion batteries and energy storage technologies that may be mass deployed,focuses on the insights of advanced optical fiber sensors into the processes of one-dimensional nano-micro-level battery material structural phase transition,electrolyte degradation,electrode-electrolyte interface dynamics to three-dimensional macro-safety *** paper contributes to understanding how to use optical fiber sensors to achieve“real”and“embedded”*** the inherent advantages of the advanced optical fiber sensor,it helps clarify the battery internal state and reaction mechanism,aiding in the establishment of more detailed *** advancements can promote the development of smart batteries,with significant importance lying in essentially promoting the improvement of system ***,with the help of smart batteries in the future,the importance of consistency can be weakened or even *** application of advanced optical fiber sensors helps comprehensively improve the battery quality,reliability,and life.

关键词： Smart battery Advanced embedded optical fiber sensor Battery internal physical/chemical state Quality-reliability-life characteristic

Facet-dependent activation of oxalic acid over hematite nanocrystals under the irradiation of visible light for efficient degradation of pollutants

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Journal of Environmental Sciences 2024年第8期142卷 204-214页

作者： Zhixiong Yang Yuan li Xiaotian wang Jiaming li Jiquan wang Gaoke Zhang Hubei Key Laboratory of Mineral Resources Processing and Environment State Key Laboratory of Silicate Materials for ArchitecturesWuhan University of TechnologyWuhan 430070China Hubei Engineering Consulting Co. Ltd.Wuhan 430071China

Naturally occurring hematite has been widely studied in the Fenton-like system for water pollutant remediation due to its abundance and ***,its inadequate catalytic activity results in difficulty in effectively degrading pollutants in the catalytic degradation system that it ***,we constructed a photochemical system composed of hematite with{001}facet of high activity facet and low-cost and non-toxic oxalic acid(OA)for the removal of various types of *** removal rate for the degradation of metronidazole,tetracycline hydrochloride,Rhodamine B,and hexavalent chromium by hematite nanoplate with the exposed{001}facet activating OA under visible light irradiation was 4.75,2.25,2.33,and 2.74 times than that by the exposed{110}facet,*** functional theory(DFT)calculation proved that the OA molecule was more easily adsorbed on the{001}facet of hematite than that on the{110}facet,which would favor the formation of the more Fe(Ⅲ)-OA complex and reactive *** addition,the reactive site of metronidazole for the attraction of radicals was identified on the basis of the DFT calculation on the molecular occupied orbitals,and the possible degradation pathway for metronidazole included carbon chain fracture,hydroxyethyl-cleavage,denitrogenation,and ***,this finding may offer a valuable direction in designing an efficient iron-based catalyst based on facet engineering for the improved activity of Fenton-like systems such as OA activation.

关键词： Hematite Facet exposure Oxalic acid activation Fenton-like system Pollutant removal

A star identification algorithm for rolling shutter exposure based on Hough transform

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Chinese Journal of Aeronautics 2024年第6期37卷 319-330页

作者： Tao wang Gangyi wang Xinguo WEI Yongyong li School of Instrumentation and Optoelectronic Engineering Beihang UniversityBeijing 100191China

The star identification algorithm usually identifies stars by angular distance ***,under high dynamic conditions,the rolling shutter effect distorts the angular distances between the measured and true star positions,leading to plethoric false matches and requiring complex and time-consuming verification for star *** identification rate hinders the application of low-noise and cost-effective rolling shutter image *** this work,we first study a rolling shutter distortion model of angular distances between stars,and then propose a novel three-stage star identification algorithm to identify distorted star images captured by the rolling shutter star *** first stage uses a modified grid algorithm with adaptive error tolerance and an expanded pattern database to efficiently eliminate spurious *** second stage performs angular velocity estimation based on Hough transform to verify the matches that follow the same distortion *** third stage applies a rolling shutter error correction method for further *** the simulation and night sky image test demonstrate the effectiveness and efficiency of our algorithm under high dynamic *** accuracy of angular velocity estimation method by Hough transform is evaluated and the root mean square error is below 0.5(°)/*** algorithm achieves a 95.7% identification rate at an angular velocity of 10(°)/s,which is much higher than traditional algorithms.

关键词： Star trackers Star identification Rolling shutter Angular velocity estimation Hough transform