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Perspective for OER electrocatalysts:Lattice engineering of clay-like frameworks with near-surface cluster active sites

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Science China(Technological Sciences) 2024年第1期67卷 330-334页

作者： ZHANG DanTong QIAN binbin XUE DongFeng Multiscale Crystal Materials Research Center Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China

Near-surface cluster active centers(NSCAC)are pivotal functional units in the catalysis of oxygen evolution reaction(OER),which exceeds the limitations imposed by the diverse coordination environments experienced in atomic and molecular active centers,thereby serving as an exceptional medium for exploring the dynamic catalytic processes of metal active sites[1,2].In the OER,the NSCAC primarily consist of the catalytic site and the first neighboring coordinating atoms.The investigation of NSCAC surpasses the exclusive reliance on the electron state regulation mechanism at the atomic level.

关键词： cluster centers exceptional

Runoff and Infiltration responses of revegetated slopes to clipping management on the northern Loess Plateau

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International Soil and Water Conservation Research 2024年第1期12卷 171-183页

作者： Qilin He binbin Li Fengbao Zhang Nan Shen Mingyi Yang The Research Center of Soil and Water Conservation and Ecological Environment Chinese Academy of Sciences and Ministry of EducationYanglingShaanxi712100China Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water ResourcesYanglingShaanxi712100China Institute of Soil and Water Conservation Northwest A&F UniversityYanglingShaanxi712100China Water and Soil Conservation Monitoring Center of Ministry of Water Resources Beijing100053China University of Chinese Academy of Sciences Beijing100049China

Large-scale vegetation restoration can reduce local watershed water yield,limit vegetation establishment and subsequent growth,and influence regional ecosystem functions.Clipping management by reducing aboveground parts of grassland was gradually recommended and adopted in Grain-for-Green project management to offset these additional issues.Thus,scientific evaluation of the effectiveness of clipping management on infiltration and runoff processes is necessary for maintaining the stability of the surface water system and the sustainability of vegetation restoration in semi-arid regions.A field simulated rainfall experiment was conducted with four managed clipping grasslands(mainly bunge needlegrass and Stipa grandis),including no clipping,light clipping,heavy clipping,and complete clipping under three slope gradients(10,20,and 30°)and three rainfall intensities(60,90,and 120 mm/h)to explore the mechanism of runoff and infiltration responses to clipping using structural equation modeling and variation partitioning based on an SCS-CN model.The results showed the runoff coefficient of the light clipping,heavy clipping,and complete clipping plots were 1.33,2.22,and 4.22 times that of the no clipping plot.The light clipping,heavy clipping,and complete clipping plots decreased the infiltration coefficients by 0%,5%,and 26%relative to the no clipping plot.Rainfall intensity dominated runoff and infiltration amounts,and clipping intensity's total effect was stronger than slope gradient.Clipping intensity and slope gradient were more influential on runoff with increasing rainfall intensity.The mutual inhibition effect was between clipping intensity and slope gradient on runoff.In order to maintain the sustainability of restoration,a 25-50%vegetation coverage after clipping maximizes the benefits of increasing runoff and maintaining enough soil water supply that prevents possible soil drought.We propose that future vegetation restoration policies should evaluate the appropriate clipping intensity;meanwhile,local physiograph

关键词： Runoff Infiltration Grassland clipping management SCS-CN model Structural equation model Variation partitioning

Transient flameout process of boron-magnesium agglomerates during combustion in oxygen-rich atmospheres

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Particuology 2024年第5期88卷 290-301页

作者： Lian Duan Zhixun Xia Yunchao Feng binbin Chen Likun Ma Jianxin Hu College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China School of Mechanical Engineering and Mechanics Xiangtan UniversityXiangtan 411105China

In this study,boron–magnesium agglomerates with varying mass ratios were prepared by drying a micron-sized boron–magnesium mixed suspension,and the combustion process of these agglomerates under different oxygen-rich concentrations were investigated using a laser ignition system.The test results showed that when the mass fraction of magnesium powder in boron-magnesium agglomerates exceeded a certain threshold(between 2%and 5%),flame extinction and reignition occurred after a significant reduction in the agglomerate volume during combustion.This process is referred to as the transient flameout process,which is affected by the magnesium content of the agglomerate and the oxygen concentration in the ambient atmosphere.An increase in the magnesium content or oxygen concentration makes this phenomenon more pronounced.During weakening of the flame intensity,a dark film gradually covered the particle surfaces.X-ray diffraction and elemental analyses of the cross-section and outer surface of the condensed combustion product suggested that the dark film is primarily composed of Mg-B-O ternary oxides.This film prevents direct contact between boron and oxygen,thereby inhibiting surface and gas-phase reactions and leading to the occurrence of the transient flameout phenomenon.

关键词： Agglomerated particle Boron–magnesium fuel Boron combustion Transient flameout process Solid fuel ramjet

A statistical analysis of the Kappa-type energy spectrum distribution of radiation belt electrons observed by Van Allen Probes

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Earth and Planetary Physics 2024年第2期8卷 368-374页

作者： LuHuai Jiao Xin Ma YuanNong Zhang TaiFeng Jin Song Fu binbin Ni Department of Space Physics School of Electronic InformationWuhan UniversityWuhan 430072China

The energy spectrum of energetic electrons is a key factor representing the dynamic variations of Earth’s Van Allen radiation belts.Increased measurements have indicated that the commonly used Maxwellian and Kappa distributions are inadequate for capturing the realistic spectral distributions of radiation belt electrons.Here we adopt the Kappa-type(KT)distribution as the fitting function and perform a statistical analysis to investigate the radiation belt electron flux spectra observed by the Van Allen Probes.By calculating the optimal values of the key KT distribution parameters(i.e.,κandθ2)from the observed spectral shapes,we fit the radiation belt electron fluxes at different L-shells under different geomagnetic conditions.In this manner,we obtain typical values of the KT distribution parameters,which are statistically feasible for modeling the radiation belt electron flux profiles during either geomagnetically quiet or active periods.A comparison of the KT distribution model results with those using the Maxwellian or Kappa distribution reveals the advantage of the KT distribution for studying the overall properties of the radiation belt electron spectral distribution,which has important implications for deepening the current understanding of the radiation belt electron dynamics under evolving geomagnetic conditions.

关键词： radiation belt electron Kappa-type distribution fitting geomagnetic storm

MSC-YOLO:Improved YOLOv7 Based on Multi-Scale Spatial Context for Small Object Detection in UAV-View

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Computers, Materials & Continua 2024年第4期79卷 983-1003页

作者： Xiangyan tang Chengchun Ruan Xiulai Li binbin Li Cebin Fu School of Computer Science and Technology Hainan UniversityHaikou570228China Hainan Blockchain Technology Engineering Research Center Hainan UniversityHaikou570228China School of Cyberspace Security(School of Cryptology) Hainan UniversityHaikou570228China

Accurately identifying small objects in high-resolution aerial images presents a complex and crucial task in thefield of small object detection on unmanned aerial vehicles(UAVs).This task is challenging due to variations inUAV flight altitude,differences in object scales,as well as factors like flight speed and motion blur.To enhancethe detection efficacy of small targets in drone aerial imagery,we propose an enhanced You Only Look Onceversion 7(YOLOv7)algorithm based on multi-scale spatial context.We build the MSC-YOLO model,whichincorporates an additional prediction head,denoted as P2,to improve adaptability for small objects.We replaceconventional downsampling with a Spatial-to-Depth Convolutional Combination(CSPDC)module to mitigatethe loss of intricate feature details related to small objects.Furthermore,we propose a Spatial Context Pyramidwith Multi-Scale Attention(SCPMA)module,which captures spatial and channel-dependent features of smalltargets acrossmultiple scales.This module enhances the perception of spatial contextual features and the utilizationof multiscale feature information.On the Visdrone2023 and UAVDT datasets,MSC-YOLO achieves remarkableresults,outperforming the baseline method YOLOv7 by 3.0%in terms ofmean average precision(mAP).The MSCYOLOalgorithm proposed in this paper has demonstrated satisfactory performance in detecting small targets inUAV aerial photography,providing strong support for practical applications.

关键词： Small object detection YOLOv7 multi-scale attention spatial context

Impact and risk factors of sepsis on long-term outcomes after spontaneous intracerebral hemorrhage

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Chinese Medical Journal 2022年第8期135卷 1006-1008页

作者： Jie Lin Minglian He binbin tan Xue Yang Yuhong Li Jishu Xian Hua Feng Yujie Chen Department of Neurosurgery and State Key Laboratory of Trauma Burn and Combined InjurySouthwest HospitalThird Military Medical University(Army Medical University)Chongqing 400038China Chongqing Clinical Research Center for Neurosurgery Southwest HospitalThird Military Medical University(Army Medical University)Chongqing 400038China Chongqing Key Laboratory of Precision Neuromedicine and Neuroregenaration Southwest HospitalThird Military Medical University(Army Medical University)Chongqing 400038China.

To the Editor:Spontaneous intracerebral hemorrhage(sICH)has a high incidence of acute cerebrovascular illness in elderly people in China,with high mortality and long-term functional impairment among survivors.However,there is still controversy over whether secondary infection during the course of hospitalization after ICH has a negative impact on long-term function.

关键词： hemorrhage mortality intracerebral

Simultaneous removal of sulfur dioxide and nitrogen oxide from flue gas by phosphorus sludge:The performance and absorption mechanism

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Chinese Journal of Chemical Engineering 2024年第1期65卷 212-221页

作者： Yuanyuan Yin Xujun Wang Lei Xu binbin He Yunxiang Nie Yi Mei Faculty of Chemical Engineering Kunming University of Science and TechnologyKunming 650500China Yunnan Provincial Key Laboratory of Energy Saving in Phosphorus Chemical Engineering and New Phosphorus Materials Kunming 650500China The Higher Educational Key Laboratory for Phosphorus Chemical Engineering of Yunnan Province Kunming 650500China

Developing low-cost and green simultaneous desulfurization and denitrification technologies is of great significance for sulfur dioxide(SO_(2))and nitrogen oxide(NO_(x))emission control at low temperatures,especially for small and medium-sized coal-fired boilers and furnaces.Herein,phosphorus sludge,an industrial waste from the production process of yellow phosphorus,has been developed to simultaneously eliminate SO_(2)and NO_(x)from coal-fired flue gas.The key factors affecting the experimental results indicate that desulfurization and denitrification efficiency of over 95%can be achieved at a low temperature of 55℃.Further,the absorption mechanism was investigated by characterizing the solid and liquid phases of the phosphorus sludge during the absorption process.The efficient removal of SO_(2)is attributed to the abundance of iron(Fe^(3+))and manganese(Mn^(2+))in the absorbent.SO_(2)can be rapidly catalyzed and converted to SO_(4)^(2-)by them.The key to NOx removal is the oxidation of NO toward watersoluble high-valent nitrogen oxides by oxidizing reactive substances induced via yellow phosphorus,which are then absorbed by water and converted to NO_(3)^(-).Meanwhile,yellow phosphorus is oxidized to phosphoric acid(H_(3)PO_(4)).The spent absorption slurry can be reused through wet process phosphoric acid production,as it contains sulfuric acid(H_(2)SO_(4)),nitric acid(HNO_(3)),and H_(3)PO_(4).Accordingly,this is a technology with broad application prospects.

关键词： Absorption Oxidation Multiphase reaction Phosphorus sludge Yellow phosphorus Low temperature

Combination of methylthio-chemistry with living crystallization-driven self-assembly toward uniformπ-conjugated nanostructures with antibacterial activity,surface tailorability,tunable morphology and dimension

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Science China Chemistry 2024年第7期67卷 2341-2352页

作者： Chuyu Duan binbin Xu Ruru Li Xiaoyu Huang Shaoliang Lin Chun Feng Shanghai Key Laboratory of Advanced Polymeric Materials School of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China School of Chemistry and Materials Science Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China Key Laboratory of Fluorine and Nitrogen Chemistry and Advanced Materials Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

Living crystallization-driven self-assembly(CDSA)provides robust access to uniformπ-conjugated nanostructures(CNSs)from block copolymers(BCPs)containing a crystallineπ-conjugated segment with controlled dimension,morphology and composition,which show appealing applications in biomedicine,photocatalysis and microelectronics.To further expand the application spectrum of these CNSs,the development of facile strategies toward diverse CNSs with varying structures/functionalities is highly desired.Herein,BCPs consisting of oligo(p-phenylene ethynylene)-b-poly(polypropyl-3-methanethiol acrylate)(OPE_(9)-bPMTPA35and OPE_(9)-b-PMTPA_(58);the subscript represents the number of repeat unit of each block)consisting of a crystallineπ-conjugated core-forming OPE_(9)segment and a corona-forming PMTPA block are synthesized.By efficient“click-type”alkylation of methylthio groups,OPE_(9)-b-PMTPA with varying contents of sulfonium unit is obtained.Uniform ribbon-like micelles with different widths and lengths can then be generated in a controlled manner via the self-seeding approach of living CDSA.Additionally,negatively charged polymeric and Ag nanoparticles can be immobilized on sulfonium/methylthio-containing shells by taking advantage of electrostatic attraction and coordination interaction,respectively.Interestingly,the ribbon-like micelles with positively charged shells exhibit antibacterial activity against E.coli.Given the ease of modification of PMTPA-based shell and attractive opto-electronic/photocatalytic properties ofπ-conjugated units,the combination of methylthio-chemistry and living CDSA opens a new avenue to generate multi-functional CNSs for widespread applications from biomedicine to photocatalysis.

关键词： crystallization-driven self-assembly block copolymer π-conjugated nanostructure methylthio-chemistry

Implications of glycemic risk index across different levels of glycated hemoglobin(HbA1c)in type 1 diabetes

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Chinese Medical Journal 2024年第4期137卷 481-483页

作者： binbin He Li Fan Chao Deng Fang Liu Yuting Xie Zhiguang Zhou Xia Li Department of Metabolism and Endocrinology National Clinical Research Center for Metabolic DiseasesKey Laboratory of Diabetes Immunology(Central South University)Ministry of EducationThe Second Xiangya Hospital of Central South UniversityChangshaHunan 410011China

To the Editor:Glycemic control in individuals with type 1 diabetes(T1D)is challenging and requires multidimensional evaluation and precise management.Glycated hemoglobin(HbA1c)is currently the gold standard for assessing glucose control and predicting diabetes prognosis.However,it exhibits limitations in terms of accuracy,which is influenced by clinical factors,^([1])and its inability to reflect information about hypoglycemia and glycemic variability.[2]Continuous glucose monitoring(CGM)has revolutionized glycemic profile evaluation by introducing novel glycemic variables that surpass conventional parameters and offer insights into critical areas for improving glycemic control.

关键词： diabetes precise insight