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Predictability of the 7·20 extreme rainstorm in Zhengzhou in stochastic kinetic-energy backscatter ensembles

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Science China Earth Sciences 2024年第7期67卷 2226-2241页

作者： Min YANG Peilong YU lifeng ZHANG Xiaobing PAN Quanjia zhong Yunying li College of Meteorology and Oceanography National University of Defense TechnologyChangsha 410073China Key Laboratory of High Impact Weather(Special) China Meteorological AdministrationChangsha 410073China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters/Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environment ChangeNanjing University of Information Science and TechnologyNanjing 210044China Department of Ocean Science Hong Kong University of Science and TechnologyHong Kong 999077China

The scale-dependent predictability of the devastating 7·20 extreme rainstorm in Zhengzhou,China in 2021 was investigated via ensemble experiments,which were perturbed on different scales using the stochastic kinetic-energy backscatter(SKEB)scheme in the WRF model,with the innermost domain having a 3-km grid *** daily rainfall(RAIN24h)and the cloudburst during 1600-1700 LST(RAIN1h)were *** demonstrated that with larger perturbation scales,the ensemble spread for the rainfall maximum widens and rainfall forecasts become closer to the *** ensembles with mesoscale or convective-scale perturbations,RAIN1h loses predictability at scales smaller than 20 km and RAIN24h is predictable for all *** in ensembles with synoptic-scale perturbations,the largest scale of predictability loss extends to 60 km for both RAIN1h and ***,the average positional error in forecasting the heaviest rainfall for RAIN24h(RAIN1h)was 400 km(50-60)*** southerly low-level jet near Zhengzhou was assumed to be directly responsible for the forecast uncertainty of *** rapid intensification in low-level cyclonic vorticity,mid-level divergence,and upward motion concomitant with the jet dynamically facilitated the *** analysis of the divergent,rotational and vertical kinetic spectra and the corresponding error spectra showed that the error kinetic energy at smaller scales grows faster than that at larger scales and saturates more quickly in all ***-scale perturbations not only boost larger-scale error growth but are also conducive to error growth at all scales through a downscale cascade,which indicates that improving the accuracy of larger-scale flow forecast may discernibly contributes to the forecast of cloudburst intensity and position.

关键词： Stochastic kinetic-energy backscatter(SKEB) Extreme rainfall Ensemble forecast Predictability

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Constructing hierarchical ZSM-5 coated with small ZSM-5 crystals via oriented-attachment and in situ assembly for methanol-to-aromatics reaction

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Frontiers of Chemical Science and Engineering 2024年第7期18卷 41-53页

作者： Ning Yang Tingjun Fu Chuntao Cao Xueqing Wu Huiling Zheng zhong li State Key Laboratory of Clean and Efficient Coal Utilization College of Chemical Engineering and TechnologyTaiyuan University of TechnologyTaiyuan 030024China

Developing hierarchical and nanoscale ZSM-5 catalysts for diffusion-limited reactions has received ever-increasing attention. Here, ZSM-5 architecture integrated with hierarchical pores and nanoscale crystals was successfully prepared via in situ self-assembly of nanoparticles-coated silicalite-1. First, the oriented attachment of amorphous nanoparticles on external surface of silicalite-1 was achieved by controlling the alkalinity of Si-Al coating solution. The partial exposure of the external surface of silicalite-1 ensured the uniform removal of silicon in the bulk phase for the creation of hierarchical pores during the subsequent desilication-recrystallization. The uniform removal of silicon species in the bulk phase was mainly due to the synergistic effect of surface protection and alkaline etching, which could be balanced by regulating the relative amount of tetrapropylammonium cation and OH– in desilication-recrystallization solution. Importantly, the removed silicon from silicalite-1 recrystallized and in situ assembled into final ZSM-5 nanocrystals induced by surface Si-Al nanoparticles. The hierarchical pores and nanoscale crystals on this integrated architecture not only promoted the removal of coke precursors from micropores but also provided large external specific surface (91 m2·g^(-1)) for coke deposition. Consequently, a much longer catalytic lifetime was achieved for methanol-to-aromatics reaction compared to conventional hollow structure ZSM-5 (84 h vs 46 h), with relatively high stability.

关键词： hierarchical ZSM-5 nanocrystal integrated architecture diffusion coke

Chiral thermally activated delayed fluorescence materials for circularly polarized organic light-emitting diodes

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Science China Chemistry 2024年第4期67卷 1097-1116页

作者： li Yuan yi-Pin Zhang You-Xuan Zheng State Key Laboratory of Coordination Chemistry Collaborative Innovation Center of Advanced MicrostructuresJiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

Chirality is an important natural characteristic of organic molecules,and chiral organic molecules have shown extensive application in areas such as pharmaceutical development and material *** from the ability to achieve circularly polarized luminescence(CPL),chiral luminescent materials have shown potential applications in anti-glare display,optical communication and,3D display,*** to the ability to harvest both singlet and triplet excitons by a fast reverse intersystem crossing process without involving noble metals,chiral thermally activated delayed fluorescence(TADF)materials with point chirality,axial chirality,planar chirality and helical chirality are regarded as the state-of-the-art materials for circularly polarized organic light-emitting diodes(CP-OLEDs).In recent years,the chiral TADF materials and CP-OLEDs have rapidly developed,but unfortunately,the dissymmetry factors(g)are far from the requirement of practical *** ideal emitters and devices should have both high efficiency and a g factor,or at least a balance between these two *** review gives an overview of recent progress in chiral TADF materials,with a particular focus on the chiral skeleton,CPL property and device ***,the molecular design concept,device structure and methods to improve the g factors of chiral materials and CP-OLEDs are also discussed.

关键词： chiral thermally activated delayed fluorescence material chiral skeleton circularly polarized luminescence circularly polarized organic light-emitting diodes dissymmetry factor

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Uncertainties of ENSO-related Regional Hadley Circulation Anomalies within Eight Reanalysis Datasets

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Advances in Atmospheric Sciences 2024年第1期41卷 115-140页

作者： Yadi li Xichen li Juan FENG yi ZHOU Wenzhu WANG Yurong HOU International Center for Climate and Environment Sciences(ICCES) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 101408China College of Global Change and Earth System Science(GCESS) Beijing Normal UniversityBeijing 100875China

El Nino-Southern Oscillation(ENSO),the leading mode of global interannual variability,usually intensifies the Hadley Circulation(HC),and meanwhile constrains its meridional extension,leading to an equatorward movement of the jet *** studies have investigated the response of HC to ENSO events using different reanalysis datasets and evaluated their capability in capturing the main features of ENSO-associated HC ***,these studies mainly focused on the global HC,represented by a zonal-mean mass stream function(MSF).Comparatively fewer studies have evaluated HC responses from a regional perspective,partly due to the prerequisite of the Stokes MSF,which prevents us from integrating a regional *** this study,we adopt a recently developed technique to construct the three-dimensional structure of HC and evaluate the capability of eight state-of-the-art reanalyses in reproducing the regional HC response to ENSO *** show that all eight reanalyses reproduce the spatial structure of HC responses well,with an intensified HC around the central-eastern Pacific but weakened circulations around the Indo-Pacific warm pool and tropical *** spatial correlation coefficient of the three-dimensional HC anomalies among the different datasets is always larger than ***,these datasets may not capture the amplitudes of the HC responses *** uncertainty is especially large for ENSO-associated equatorially asymmetric HC anomalies,with the maximum amplitude in Climate Forecast System Reanalysis(CFSR)being about 2.7 times the minimum value in the Twentieth Century Reanalysis(20CR).One should be careful when using reanalysis data to evaluate the intensity of ENSO-associated HC anomalies.

关键词： regional Hadley circulation ENSO atmosphere-ocean interaction reanalysis data

Towards accurate mapping of loess waterworn gully by integrating google earth imagery and DEM using deep learning

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International Soil and Water Conservation Research 2024年第1期12卷 13-28页

作者： Rong Chen yi Zhou Zetao Wang ying li Fan li Feng Yang School of Geography and Tourism Shaanxi Normal UniversityXi'an710119China National Experiment and Teaching Demonstration Center for Geography Xi'an710119China SuperMap Software Co. Ltd.Beijing100015China School of Environmental Science and Engineering Southern University of Science and TechnologyShenzhen518055China

Accurate mapping of loess waterworn gully(LWG)is essential to further study gully erosion and geomorphological evolution for the Chinese Loess Plateau(CLP).Due to the vertical joint and collapsibility of loess,LWGs have the characteristics of zigzag and unique slope abruptness under synthetic action of hydraulic force and *** forces existing LWG mapping methods to either focus on the improvement of mapping accuracy or center on the increase of mapping ***,simultaneously achieving accurate and efficient mapping of LWG is still in its infancy under complex topographic ***,we proposed a method that innovatively integrates the loess slope abruptness feature into an improved deep learning semantic segmentation framework for LWG mapping using 0.6 m Google imagery and 5 m DEM *** selected four study areas representing typical loess landforms to test the performance of our *** proposed method can achieve satisfactory mapping results,with the F1 score,mean Intersection-over-Union(mIoU),and overall accuracy of 90.5%,85.3%,and 92.3%,*** addition,the proposed model also showed significant accuracy improvement by inputting additional topographic information(especially the slope of slope).Compared with existing algorithms(Random forests,original DeepLabV3+,and Unet),the proposed approach in this study achieved a better accuracy-efficiency ***,the method can ensure high accuracy and efficiency of the LWG mapping for different loess landform types and can be extended to study various loess gully mapping and water and soil conservation.

关键词： Loess waterworn gully Topographic information Mapping Deep learning Soil erosion Loess plateau

Oral pyroptosis nanoinhibitor for the treatment of inflammatory bowel disease

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Nano Research 2024年第3期17卷 1748-1759页

作者： Zhenxing Zhu Dongtao Zhou yi yin Zhun li Zhen Guo Yongchun Pan Yanfeng Gao Jingjing Yang Weiming Zhu Yujun Song yi li Department of General Surgery Affiliated Jinling HospitalMedical SchoolNanjing UniversityNanjing 210093China College of Engineering and Applied Sciences State Key Laboratory of Analytical Chemistry for Life ScienceNanjing UniversityNanjing 210023China Department of General Surgery Affiliated Drum Tower HospitalMedical SchoolNanjing UniversityNanjing 210008China Department of Biochemistry and Molecular Biology School of Medicine&Holistic Integrative MedicineJiangsu Collaborative Innovation Center of Chinese Medicinal Resources IndustrializationNanjing University of Chinese MedicineNanjing 210023China

Inflammatory bowel disease(IBD)is an autoimmune gastrointestinal disease characterized by chronic relapsing inflammation of the *** pyroptosis that exists in the inflamed intestine can activate damage signals and aggravate local inflammation in ***,we designed an oral pyroptosis nanoinhibitor,DXMS@CuM@PPADT@PSS(DCMP),which can target intestinal lesions,and respond to reactive oxygen species(ROS)to release active sites and drugs at the *** can inhibit the activation of the nucleotide-binding domain and leucine-rich repeat family pyrin domain containing 3(NLRP3)inflammasomes by scavenging ROS,resulting in the down-regulation of gasdermin D(GSDMD)cleavage thus inhibiting *** also improved intestinal barrier function,decreased inflammatory cytokine levels,and increased the diversity of gut microbiota in mice with *** work is believed to expand the biomedical application of nanomaterials for innate immunity modulation.

关键词： inflammatory bowel disease nanoinhibitors pyroptosis synergistic therapy antioxidant

Effects of landscape fragmentation of plantation forests on carbon storage in the Loess Plateau,China

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Journal of Arid Land 2024年第2期16卷 266-281页

作者： LEI Hangyu DUAN Dantong CHEN yi GUO Huifeng li Jiangtao li Xiang College of Landscape Architecture and Art Northwest A&F UniversityYangling 712100China

Tree plantation and forest restoration are the major strategies for enhancing terrestrial carbon sequestration and mitigating climate *** Grain for Green Project in China has positively impacted global carbon sequestration and the trend towards fragmentation of plantation *** studies have been conducted on changes in plantation biomass and stand structure caused by fragmentation,and the effect of fragmentation on the carbon storage of plantation forests remains *** study evaluated the differences between carbon storage and stand structure in black locust forests in fragmented and continuous landscape in the Ansai District,China and discussed the effects of ecological significance of four landscape indices on carbon storage and tree *** used structural equation modelling to explore the direct and indirect effects of fragmentation,edge,abiotic factors,and stand structure on above-ground carbon *** at breast height(DBH)in fragmented forests was 53.3%thicker,tree density was 40.9%lower,and carbon storage was 49.8%higher than those in continuous forests;for all given DBH>10 cm,the trees in fragmented forests were shorter than those in continuous *** patch area had a negative impact on carbon storage,i.e.,the higher the degree of fragmentation,the lower the density of the tree;and fragmentation and distance to edge(DTE)directly increased canopy ***,canopy coverage directly decreased carbon storage,and fragmentation directly increased carbon storage and tree *** non-commercial forests,fragmentation reduces the carbon storage potential of plantation,and the influence of patch area,edge,and patchy connection on plantation should be considered when follow-up trees are planted and for the plantation ***,expanding the area of plantation patches,repairing the edges of complex-shaped patches,enhancing the connectivity of similar patches,and applying nutrients to plantation forests at regular i

关键词： landscape fragmentation plantation carbon storage tree allometry tree density structural equation modelling

Effi cacy of partial and complete resuscitative endovascular balloon occlusion of the aorta in the hemorrhagic shock model of liver injury

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World Journal of Emergency Medicine 2024年第1期15卷 10-15页

作者： yi Shan Yang Zhao Chengcheng li Jianxin Gao Guogeng Song Tanshi li Department of Emergency Medicine Chinese PLA Medical SchoolBeijing 100853China Department of Emergency Medicine the Sixth Medical Center of PLA General HospitalBeijing 100048China Department of Emergency Medicine School of MedicineSouth China University of TechnologyGuangzhou 510006China Department of Emergency Medicine the First Medical Center of PLA General HospitalBeijing 100853China

BACKGROUND:Resuscitative endovascular balloon occlusion of the aorta(REBOA)can temporarily control traumatic ***,its prolonged use potentially leads to ischemia-reperfusion injury(IRI).Partial REBOA(pREBOA)can alleviate ischemic burden;however,its security and eff ectiveness prior to operative hemorrhage control remains ***,we aimed to estimate the effi cacy of pREBOA in a swine model of liver injury using an experimental sliding-chamber ballistic ***:Twenty Landrace pigs were randomized into control(no aortic occlusion)(n=5),intervention with complete REBOA(cREBOA)(n=5),continuous pREBOA(C-pREBOA)(n=5),and sequential pREBOA(S-pREBOA)(n=5)*** the cREBOA and C-pREBOA groups,the balloon was inflated for 60 *** hemodynamic and laboratory values were compared at various observation time *** samples immediately after animal euthanasia from the myocardium,liver,kidneys,and duodenum were collected for histological assessment using hematoxylin and eosin ***:Compared with the control group,the survival rate of the REBOA groups was prominently improved(all Pliver injury,a 60-minute pREBOA resulted in improved survival rate and was effective in maintaining reliable aortic pressure,despite persistent *** tolerance time for aortic occlusion in Zone I for non-compressible torso hemorrhage was feasible with both continuous partial and sequential partial measures,and the significant improvement in the severity of acidosis and distal organ injury was observed in the sequential pREBOA.

关键词： Non-compressible torso hemorrhage liver injury Ischemia-reperfusion injury Resuscitative endovascular balloon occlusion of the aorta

MPI/OpenMP-Based Parallel Solver for Imprint Forming Simulation

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 461-483页

作者： Yang li Jiangping Xu Yun liu Wen zhong Fei Wang School of Mechanical Engineering Jiangsu UniversityZhenjiang212016China School of Mechanical Engineering Wuhan Polytechnic UniversityWuhan430023China Shenyang Mint Company limited Shenyang110092China

In this research,we present the pure open multi-processing(OpenMP),pure message passing interface(MPI),and hybrid MPI/OpenMP parallel solvers within the dynamic explicit central difference algorithm for the coining process to address the challenge of capturing fine relief features of approximately 50 *** such precision demands the utilization of at least 7 million tetrahedron elements,surpassing the capabilities of traditional serial programs previously *** mitigate data races when calculating internal forces,intermediate arrays are introduced within the OpenMP *** helps ensure proper synchronization and avoid conflicts during parallel ***,in the MPI implementation,the coins are partitioned into the desired number of *** division allows for efficient distribution of computational tasks across multiple *** simulation examples are conducted to compare the three solvers with serial programs,evaluating correctness,acceleration ratio,and parallel *** results reveal a relative error of approximately 0.3%in forming force among the parallel and serial solvers,while the predicted insufficient material zones align with experimental ***,speedup ratio and parallel efficiency are assessed for the coining process *** pureMPI parallel solver achieves a maximum acceleration of 9.5 on a single computer(utilizing 12 cores)and the hybrid solver exhibits a speedup ratio of 136 in a cluster(using 6 compute nodes and 12 cores per compute node),showing the strong scalability of the hybrid MPI/OpenMP programming *** approach effectively meets the simulation requirements for commemorative coins with intricate relief patterns.

关键词： Hybrid MPI/OpenMP parallel computing MPI OpenMP imprint forming