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Mechanism investigation of A-site doping on modulating electronic band structure and photocatalytic performance towards CO_(2) reduction of LaFeO_(3) perovskite

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Nano Research 2024年第5期17卷 3733-3744页

作者： Chi Cao Jinshuo Li yang Hu Lin Zhang Wensheng yang State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin UniversityChangchun 130012China Engineering Research Center for Nanomaterials Henan UniversityKaifeng 475004China

Three kinds of metal atoms with different valence electronic configurations,Bi(6s^(2)6p^(3)),Y(4d^(1)5s^(2)),and Ce(4f^(1)5d^(1)6s^(2)),were selected to investigate the effect of A-site(La^(3+))doping on electronic band structure,photoelectric properties,and photocatalytic performance of LaFeO_(3) *** was identified that the Bi doped LaFeO_(3) presented significantly improved photocatalytic activity towards the reduction of CO_(2),while the Y or Ce doped LaFeO_(3) displayed decreased photocatalytic activity compared to the pristine LaFeO_(3).It was revealed that doping of all the three metal atoms resulted in narrowed band gap and thus extended light absorption of LaFeO_(3) by lowering its conduction band minimum(CBM).The recombination rate and mobility of the charge carriers were represented by the relative effective mass(D)between holes and electrons for pristine and A-site doped LaFeO_(3).The doping of Bi resulted in increased D value,attributed to the Bi 6s electron states at the valence band maximum(VBM),and thus promoted separation and transfer of the charge carriers and improved photocatalytic activity of LaFeO_(3).In contrast,the doping of Ce resulted in significantly decreased D value,induced by the highly localized Ce 4f hole states at the CBM,and thus higher recombination rate of the charge carriers and decreased photocatalytic activity of LaFeO_(3).Furthermore,the Y doped LaFeO_(3) with a slightly decreased D value presented slightly increased recombination rate of the charge carriers and thus decreased photocatalytic *** a work provides new insights into the A-site doping in LaFeO_(3) perovskite,which should be helpful for optimizing the electronic band structure and activity of perovskite-type photocatalysts at atomic level.

关键词： A-site doping electronic band structure charge carrier behavior photocatalytic CO_(2)reduction perovskite-type photocatalytsts

Influence of water coupling coefficient on the blasting effect of red sandstone specimens

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International Journal of Coal Science & Technology 2024年第1期11卷 148-166页

作者： yang Li Renshu yang Yanbing Wang Dairui Fu School of Mechanics and Civil Engineering China University of Mining and Technology(Beijing)Beijing100083China School of Civil and Resource Engineering University of Science and Technology BeijingBeijing100083China

This study investigates the impact of different water coupling coefficients on the blasting effect of red *** analysis is based on the theories of detonation wave and elastic wave,focusing on the variation in wall pressure of the blasting *** DDNP explosive as the explosive load,blasting tests were conducted on red sandstone specimens with four different water coupling coefficients:1.20,1.33,1.50,and *** study examines the morphologies of the rock specimens after blasting under these different water coupling ***,the fractal dimensions of the surface cracks resulting from the blasting were calculated to provide a quantitative evaluation of the extent of rock *** scanning and 3D reconstruction were performed on the post-blasting specimens to visually depict the extent of damage and fractures within the ***,the volume fractal dimension and damage degree of the post-blasting specimens are *** findings are then combined with numerical simulation to facilitate auxiliary *** results demonstrate that an increase in the water coupling coefficient leads to a reduction in the peak pressure on the hole wall and the crushing zone,enabling more of the explosion energy to be utilized for crack propagation following the *** specimens exhibited distinct failure patterns,resulting in corresponding changes in fractal *** simulated pore wall pressure–time curve validated the derived theoretical results,whereas the stress cloud map and explosion energy-time curve demonstrated the buffering effect of the water *** the water coupling coefficient increases,the buffering effect of the water medium becomes increasingly prominent.

关键词： Water coupling coefficient Radial uncoupled charge Numerical simulation Fractal dimension

Dynamic collapse characteristics of the tunnel face induced by the shutdown of earth pressure balance shields(EPB):A 3D material point method study

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Underground Space 2024年第3期16卷 164-182页

作者： Shuying Wang Tingyu Liu Xiangcou Zheng Junsheng yang Feng yang School of Civil Engineering Central South UniversityChangsha 410075HunanChina Tunnel and Underground Engineering Research Center of Central South University Changsha 410075HunanChina Hunan Provincial Key Laboratory for Disaster Prevention and Mitigation of Rail Transit Engineering Structures Central South UniversityChangsha 410075HunanChina

The collapse of the tunnel face is a prevalent geological disaster in *** study employs a three-dimensional(3D)material point method(MPM)to simulate the dynamic collapse process and post-failure mechanisms of the tunnel *** specific focus is on the scenario where the auxiliary air pressure balanced shield with a partially filled chamber is shut *** assess the suitability of the 3D MPM,numerical solutions are compared with the results from small-scale experimental ***,a series of large-scale numerical simulations is conducted to explore the dynamic collapse characteristics of the tunnel face induced by the shutdown of the EPB shield under various support air pressures and cutter head *** temporal evolution of the accumulated soil masses in the soil chamber and ground responses under different support air pressures,cutter head types and opening ratios are *** particular,the associated surface subsidence due to the tunnel face collapse is determined and compared with empirical *** results confirm the applicability of the 3D MPM for simulating the large-scale tunnel face collapse scenarios,spanning from small to large deformation analysis.

关键词： Large deformation Material point method Partially filled chamber Post-failure mechanism Shield tunnel Tunnel face collapse

Light People:*** Mazur speaks about ultrafast optics and education

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Light(Science & Applications) 2024年第3期13卷 402-406页

作者： Chenzi Guo yang Li Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchunChina State Key Laboratory of Precision Measurement Technology and Instrument Department of Precision InstrumentTsinghua UniversityBeijingChina

*** Mazur is a great influencer over and beyond the optics *** a physicist,he is a pioneer of ultrafast optics and was one of the inventors of colliding-pulse mode-locked *** an educator,he not only gave talks to thousands,but also revolutionized teaching with his globally renowned methodology“Peer Instruction”.As a leader and entrepreneur,he co-founded several companies and was President of Optica(formerly the Optical Society)and currently is the Chair of the Optica ***,Light:Science&Applications talked with *** Mazur about his opinions on research,education and *** full interview video can be found in the Supplementary File.

关键词： optics education companies

A novel predictive braking energy recovery strategy for electric vehicles considering motor thermal protection

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Science China(Technological Sciences) 2024年第4期67卷 1253-1269页

作者： yang Chao SUN TongLin yang LiuQuan ZHANG YuHang WANG WeiDa School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100084China

Braking energy recovery(BER)aims to recover the vehicle's kinetic energy by coordinating the motor and mechanical braking torque to extend the driving range of the electric vehicle(EV).To achieve this goal,the motor/generator mode requires frequent switching and prolonged operation during *** this case,the motor temperature will unavoidably rise,potentially triggering motor thermal protection(MTP).Activating MTP increases the risk of motor component failure,and the EV typically disables the BER ***,maximizing BER while reducing the risk of motor overheating is a challenging *** address this issue,this article proposes a predictive BER strategy with MTP using the non-smooth Pontryagin Minimum Principle(NSPMP)for ***,a Markov long short-term memory(MLSTM)model is designed to obtain future velocity ***,the BER problem with MTP in the studied EV is embedded in a model predictive control(MPC)***,under the MPC framework,the NSPMP strategy is proposed to resolve the problem of ***,the performance of the proposed strategy is verified through simulation and a hardware-in-loop *** results show that in two real-world driving cycles,compared to the rule-based strategy,the proposed strategy reduced power consumption by 1.24%and0.96%,respectively,and effectively limited motor ***,under global cycle conditions,this strategy demonstrated better MTP control performance compared to other benchmark strategies.

关键词： electric vehicle braking energy recovery strategy motor thermal protection non-smooth PMP

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Material point method simulation of hydro-mechanical behaviour in twophase porous geomaterials: A state-of-the-art review

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第6期16卷 2341-2350页

作者： Xiangcou Zheng Shuying Wang Feng yang Junsheng yang School of Civil Engineering Central South UniversityChangsha410075China Geo-Engineering Section Faculty of Civil Engineering and GeosciencesDelft University of TechnologyDelftthe Netherlands

The material point method(MPM)has been gaining increasing popularity as an appropriate approach to the solution of coupled hydro-mechanical problems involving large *** this paper,we survey the current state-of-the-art in the MPM simulation of hydro-mechanical behaviour in two-phase porous *** review covers the recent advances and developments in the MPM and their extensions to capture the coupled hydro-mechanical problems involving large *** focus of this review is aiming at providing a clear picture of what has or has not been developed or implemented for simulating two-phase coupled large deformation problems,which will provide some direct reference for both practitioners and researchers.

关键词： Coupled problems Hydro-mechanical behaviour Large deformation Material Point Method(MPM)

Yemazhui(Herba Eupatorii Lindleyani)ameliorates lipopolysaccharide-induced acute lung injury via modulation of the toll-like receptor 4/nuclear factor kappa-B/nod-like receptor family pyrin domain-containing 3 protein signaling pathway and intestinal flor

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Journal of Traditional Chinese Medicine 2024年第2期44卷 303-314页

作者： REN Li HAI yang yang Xue LUO Xianqin Chongqing Key Laboratory of Traditional Chinese Medicine for Prevention and Cure of Metabolic Diseases College of Traditional Chinese MedicineChongqing Medical UniversityChongqing 400016China College of Basic Medicine Chongqing Medical UniversityChongqing 400016China

OBJECTIVE:To investigate the impact of Yemazhui(Herba Eupatorii Lindleyani,HEL)against lipopolysaccharide(LPS)-induced acute lung injury(ALI)and explore its underlying mechanism in ***:The chemical constituents of HEL were analyzed by ultra-high performance liquid chromatographyquadrupole time-of-flight mass spectrometry ***,HEL was found to suppress LPS-induced ALI in ***-week-old male Sprague-Dawley rats were randomly divided into 6 groups:control,LPS,Dexamethasone(Dex),HEL low dose 6 g/kg(HEL-L),HEL medium dose 18 g/kg(HEL-M)and HEL high dose 54 g/kg(HEL-H)*** model rats were intratracheally injected with 3 mg/kg LPS to establish an ALI *** counts,lung wet/dry weight ratio,as well as myeloperoxidase(MPO)activity were determined followed by the detection with hematoxylin and eosin staining,enzyme linked immunosorbent assay,quantitative real time polymerase chain reaction,western blotting,immunohistochemistry,and ***,to explore the effect of HEL on ALI-mediated intestinal flora,we performed 16s rRNA sequencing analysis of intestinal ***:HEL attenuated LPS-induced inflammation in lung tissue and intestinal flora *** study indicated that HEL suppressed the lung coefficient and wet/dry weight ratio of LPS-induced ALI in rats,inhibited leukocytes exudation and MPO activity,and improved the pathological injury of lung *** addition,HEL reduced the expression of tumor necrosis factoralpha,interleukin-1beta(IL-1β)and interleukin-6(IL-6)in bronchoalveolar lavage fluid and serum,and inhibited nuclear displacement of nuclear factor kappa-B p65(NF-κBp65).And 18 g/kg HEL also reduced the expression levels of toll-like receptor 4(TLR4),myeloid differentiation factor 88,NF-κBp65,phosphorylated inhibitor kappa B alpha(phospho-IκBα),nod-like receptor family pyrin domain-containing 3 protein(NLRP3),IL-1β,and interleukin-18(IL-18)in lung tissue,and regulated intestinal flora disturban

关键词： Yemazhui(Herba Eupatorii Lindleyani) acute lung injury anti-inflammation toll-like receptor 4 nuclear factor kappa-B nod-like receptor family pyrin domain-containing 3 protein signal transduction gastrointestinal microbiome

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Prospects of sediment deposition at small watershed scale in the black soil region of Northeast China: A mini review

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Pedosphere 2024年第1期34卷 30-35页

作者： Guanghui ZHANG yang yang Yingna LIU Zhiqiang WANG State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China School of Geography Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China

Sediment deposition is one of the most significant processes in small watersheds characterized by gentle long hillslopes in the black soil(Mollisol)region of Northeast China, as indicated by severe ephemeral gully and gully erosion on hillslopes and very low sediment concentrations in river *** reviews have been conducted to summarize the related research in this region. The objectives of this review were to identify the potential factors influencing sediment deposition, review related studies, and propose future research needs in the black soil region of Northeast China. Sediment deposition is controlled by the deficit between sediment transport capacity of flow and sediment load. Hence, all factors affecting flow transport capacity and sediment load directly affect sediment deposition. For a specific small watershed, the change in slope gradient along the flow path is the key factor affecting sediment deposition. Shelterbelts, ridge tillage systems, terraces, grass strips, road distribution, ponds and reservoirs, and land-use patterns also influence the spatial distribution and rate of deposition. The trace method has been widely used to quantify sediment deposition in this region. The results of cesium-137(^(137)Cs),lead-210(^(210)Pb), and magnetic susceptibility reveal that serious deposition occurs on the back and foot slopes. Distinct deposition occurs in front of contour shelterbelts. Future studies should focus on the methodology, spatial and temporal variations, dominant influencing factors and their mechanisms, and the potential effects on land productivity within specific small watersheds and across the black soil region. This review provides insights into the sediment deposition process in small watersheds characterized by gentle, long hillslopes.

关键词： Mollisol sedimentation soil and water conservation soil erosion soil redistribution

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Influence of Real Gas Properties on Aerodynamic Losses in a Supercritical CO2 Centrifugal Compressor

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Journal of Thermal Science 2024年第6期33卷 2032-2046页

作者： yang Mingyang CAI Ruikai ZHUGE Weilin yang Bijie ZHANG yangjun School of Mechanical Engineering Shanghai Jiao Tong University School of Vehicle and Mobility State Key Laboratory of Intelligent Green Vehicle and MobilityTsinghua University Department of Mechanical Engineering Imperial College London

Supercritical carbon dioxide（SCO2） centrifugal compressor is a key component of a closed Brayton cycle system based on SCO2.A comprehensive understanding of the loss mechanism within the compressor is vital for its optimized ***,the physical properties of SCO2are highly nonlinear near the critical point,and the internal flow of the compressor is closely related to its properties,which inevitably influences the generation of aerodynamic losses within the *** paper presents a comprehensive investigation of the compressor's loss mechanism with an experimentally validated numerical *** real gas model of CO2embodied in the Reynolds-Averaged Navier-Stokes（RANS） model was used for the ***,the numerical simulation method was validated against the experimental results of Sandia ***,performance and loss distribution of the compressor were compared among three fluids including SCO2,ideal CO2（ICO2） and ideal air（IAir）.The results showed that the performance of SCO2was comparable to IAir under low flow coefficient,however markedly inferior to the other two fluids at near choke *** distribution among the three fluids was *** the impeller,SCO2was the most inefficient,followed by ICO2and *** discrepancies were magnified as the flow coefficient *** is due to a stronger Blade-to-Blade pressure gradient that intensifies boundary layer accumulation on walls of the shroud/***,owing to the reduced sonic speed of SCO2,a shock wave appears earlier at the throat region and SCO2encounters more intense boundary layer separation.

关键词： centrifugal compressor loss mechanism real gas properties SCO2