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Investigation on the vortical structures by the liutex method in turbulent channels at Re_(τ)=1.0 with scalloped and triangular riblet control

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Journal of Hydrodynamics 2024年第1期36卷 35-52页

作者： Zhang-dan yu Shang {1. Hai-dong yu Bi-yu Pang Xin Dong Yi-qian wang School of Mathematical Sciences Soochow UniversitySuzhou215006China beijing Institute of Astronautical System Engineering Beijing100076China

Riblets are a series of small protrusions formed along the flow direction,which have been extensively studied as a passive turbulent drag reduction *** and numerical simulations have shown that well-designed riblets can significantly reduce drag in turbulent flows,making them highly promising and valuable for various *** this study,we focus on a scalloped riblet,which is designed by smoothly connecting two third-order polynomials,and thus the sharpness of the tip and the curvature of the valley can be well *** conduct direct numerical simulations of turbulent channel with smooth plate,scalloped riblet-mounted and triangular riblet-mounted *** in wall units of W^(+)=2. and height-width ratio ofγ=0.5 are selected for both riblet *** with the smooth plate case,the scalloped riblet case achieves an 8.68%drag reduction,while the triangular riblet case achieves a 4.79%drag *** obtained drag reduction rate of the triangular riblet is consistent with previous experiments and simulations,and the results indicate that the scalloped riblet is more effective in reducing drag and deserves further *** compare turbulent statistics of the scalloped riblet case with those of the triangular riblet *** mean velocity profiles of riblets are similar,but both the Reynolds shear stress and second-order statistics of velocity fluctuations and {1.tex are significantly reduced in the scalloped riblets controlled turbulent channel,indicating that the scalloped riblet can more effectively suppress the spanwise and wall-normal turbulent intensity near the *** also compare the pre-multiplied spectra of streamwise velocity and streamwise {1.tex component for the three cases to investigate the energy distribution and characteristics of {1.tex *** {1.tex vortex identification method is also utilized to analyze the instantaneous flow field,which provides insights into the flow field and could be bene

关键词： liutex vector riblet drag reduction tip sharpness turbulent channel scalloped

Polyoxometalate as the assembly material to self-assembled Ni(OH)_(2. nanosheets with electrocatalytic performance

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Nano Research 2024年第8期17卷 7061-7067页

作者： Danyang He Tianyang Li Luozhen jiang Fei {1. Zihao Xing Nan {1. Zhiyu Jia Guo-yu Yang Key Laboratory of Cluster Science Ministry of EducationSchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081China Shanghai Advanced Research Institute Chinese Academy of ScienceShanghai 201210China Key Laboratory of Polyoxometalate and Reticular Material Chemistry of Ministry of Education Facluty of ChemistryNortheast Normal UniversityChangchun 130024China

Developing non-noble metal-based electrocatalyst with high catalytic activity is essential for advancing hydrogen energy *** study introduces a hydrothermal method for synthesizing order Ni(OH)_(2. nanosheets,with H_(3)O_(40)PW_(1.0}(denoted as PW_(1.0})loaded onto reduced graphene oxide(rGO)coated on nickel foam(referred to as PW_(1.0}-Ni(OH)_(2./rGO).This method contrasts with the electrodeposition of Ni(OH)_(2.,where PW_(1.0} is added to the synthetic system to direct the assembly and morphology of the Ni(OH)_(2. through a hydrothermal *** this work,the nickel foam acts dual roles as both the substrate and the source of nickel for the formation of Ni(OH)_(2..The PW_(1.0}-Ni(OH)_(2./rGO nanosheets,when successfully prepared and loaded onto the nickel foam(NF),exhibited superior electrocatalytic activity for the hydrogen evolution reaction(HER)in an alkaline electrolyte,achieving a current density of 1. mA·cm^(-2. at an overpotential of 69 ***,we endeavored to expand the application of this material towards the oxygen evolution reaction(OER)by preparing PW_(1.0}-(Fe/Co)Ni(OH)_(2./rGO through the addition of metal *** nanocomposite displayed outstanding electrocatalytic activity in alkaline electrolytes,with a current density of 1. mA·cm^(-2.at an overpotential of 2.1.mV,and demonstrated excellent stability over a 50 h period in a 1.M KOH *** results presented in this paper offer an effective strategy for the preparation of polyoxometalate-based inorganic materials with diverse functionalities,applicable to both HER and OER.

关键词： polyoxometalate Ni(OH)_(2. assembly hydrogen evolution reaction oxygen evolution reaction

A distributed hydrological model with its application to the Jinghe watershed in the Yellow River Basin

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Science china(Technological Sciences) 2004年第z1期47卷 60-71页

作者： wang Zhonggen1, ZHENG Hongxing1, liu changming1, , WU Xianfeng2.2.& ZHAO Weimin3 1. Key Laboratory of Water Cycle & Related Land Surface Processes, Institute of Geographic Science and Natural Resources Research, Chinese Academy of Sciences, {2. 100101, china 2. Institute of Environmental Science, {2. normal university, beijing 100875, china 3. Water Resources Conservation Committee of Yellow River, Zhengzhou 450003, china Chinese Acad Sci Key Lab Water Cycle & Related Land Surface Proc Inst Geog Sci & Nat Resources Res Beijing 100101 Peoples R China beijing {1. Univ Inst Environm Sci Beijing 100875 Peoples R China Water Resources Conservat Comm Yellow River Zhengzhou 450003 Peoples R China

For the purpose of water resources management in the Yellow River Basin with highly spatial difference, a daily distributed hydrological model was proposed, of which the determination of spatially-distributed parameters and model inputs processing were performed by means of GIS/RS. In the model, the computation of runoff yield was based on the topography index method and flow routing was modeled by Maskingum method. The operation of the model is followed by means of “command structure” technique based upon the topography of river network. A case study using the model was conducted for the Jinghe watershed, which locates at the middle Yellow River Basin. The simulation of the hydrological processes in 1.96 has shown that water quantity balance errors were less than 5% and the Nash-Sutcliffe coefficient arrived at 0.7, indicating that the model structure is justifiable, and the precision of the model can satisfy the purpose of water resources management.

关键词： distributed hydrological model, structure and equation, GIS and RS, Jinghe Basin, Yellow River Basin.

Spatio-temporal pattern analysis of single-trial EEG signals recorded during visual object recognition

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Science china(Information Sciences) 2011年第12期54卷 2519-2527页

作者： wang {1. 1., HU XiaoPing 3 , YAO Li 1.2., XIONG Shi 2.& ZHANG JiaCai 2.1.National Key Laboratory of Cognitive Neuroscience and Learning, {2. normal university, beijing 100875, china 2.College of Information Science and Technology, {2. normal university, beijing 100875, china 3 Biomedical Imaging Technology Center, Emory university/Georgia Institute of Technology, Atlanta 3032., USA 1. National Key Laboratory of Cognitive Neuroscience and Learning Beijing Normal University Beijing 100875 China3. Biomedical Imaging Technology Center Emory University/Georgia Institute of Technology Atlanta 30322 USA2. College of Information Science and Technology Beijing Normal University Beijing 100875 China

Object discrimination is a fundamental cognitive function for human brains. In this study, we utilized an analysis approach for single-trial electroencephalography (EEG) to analyze the spatio-temporal activation patterns of visual objects processing in human brains, and attempted to apply it to discriminate different visual objects. The spatial patterns were respectively extracted from scalp EEG and the reconstructed cortical sources, while the experiment participants were perceiving 4 different categories of visual objects (faces, buildings, cats and cars). By classifying the patterns extracted from single-trial EEG, the presented visual objects could be discriminated by a computer, and the classification accuracies may provide a quantitative index to evaluate the spatial differences of the brain activations related to different visual objects. Our results demonstrated that the spatial patterns on both the scalp and the sources levels resulted in higher classification accuracies than chance rate. We also examined the classification results using temporally non-overlapping time intervals of different event-related potential (ERP) components. The temporal changes of classification accuracies may reflect the temporal distribution of the discriminative information in the EEG responses. The present pattern extraction and classification methods may compose a computational model for single-trial EEG data analysis in investigations of the spatio-temporal activation patterns for object recognition. These spatio-temporal patterns in EEG may be useful to identifying the discriminative spatial areas and time stages to improve the accuracies and efficiencies of object discrimination. In addition, investigating and utilizing humans'cognitive mechanisms of object recognition may improve computers' processing efficiency of visual information.

关键词： EEG spatio-temporal pattern object recognition single-trial analysis visual information processing

Co/N co-doped flower-like carbon-based phase change materials toward solar energy harvesting

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Aggregate 2024年第1期5卷 321-330页

作者： Xiao Chen Lei wang Yan Gao Yang Li Xiaowei Zhang {1. jiang Ge wang Institute of Advanced Materials Beijing Normal UniversityBeijingChina beijing Advanced Innovation Center for Materials Genome Engineering Beijing Key Laboratory of Function Materials for Molecule and Structure ConstructionSchool of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijingChina

The photothermal conversion capacity of pristine organic phase change materials(PCMs)is inherently insufficient in solar energy *** upgrade their photothermal conversion capacity,we developed bimetallic zeolitic imidazolate framework(ZIF)derived Co/N co-doped flower-like carbon(Co/N-FLC)-based composite PCMs toward solar energy harvesting.3D interconnected carbon framework with low interfacial thermal resistance,abundant carbon defects and high content of nitrogen doping,excellent localized surface plasmon resonance(LSPR)effect of Co nanoparticles,and light absorber Co_(3)ZnC in Co/N-FLC synergistically upgrade the photothermal capacity of(polyethylene glycol)PEG@Co/N-FLC composite PCMs with an ultrahigh photothermal conversion efficiency of 94.8%under 0.1. W/cm^(2..Uniformly anchored Co and Co_(3)ZnC nanoparticles in carbon framework guarantee excellent photon capture *** carbon nanotubes(CNTs)in 2. carbon nanosheets further accelerate the rapid transport of phonons by constructing cross-connected heat transfer ***,PEG@Co/N-FLC exhibits a thermal energy storage density of 1.0.69 J/g and excellent thermal stability and durable ***,PEG@Co/N-FLC composite PCMs are promising candidates to accelerate the efficient utilization of solar energy.

关键词： bimetallic ZIF Co/N co-doped carbon phase change materials photothermal conversion thermal energy storage

Synthesis of spherical nano-ZSM-5 zeolite with intergranular mesoporous for alkylation of ethylbenzene with ethanol to produce m-diethylbenzene

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Chinese Journal of Chemical Engineering 2024年第3期67卷 298-309页

作者： Siyue {1. Jinhong Li Qingxin Xu Shengjie Song yu'ni jiang Lidong Chen Xin Shi Weiguo Cheng Faculty of Chemistry and Chemical Engineering Liaoning Normal UniversityDalian 110629China beijing Key Laboratory of Ionic Liquids Clean Process Key Laboratory of Green Process and EngineeringInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China

Catalytic synthesis of m-diethylbenzene(m-DEB)through alkylation of ethylbenzene(EB)may be a promising alternative route in comparison with traditional rectification of mixed DEB,for which the top priority is to develop efficient and stable heterogeneous ***,the spherical nano-ZSM-5 zeolite with abundant intergranular mesoporous is synthesized by the seed-mediated growth method for alkylation of EB with ethanol to produce *** results show that the spherical nano-ZSM-5 zeolite exhibits better stability and higher alkylation activity at a lower temperature than those of commercial micropore *** then,the spherical nano-ZSM-5 is further modified by La_(2.O_(3) through acid treatment followed by immersion *** acid treatment causes nano-ZSM-5 to exhibit the increased pore size but decreased the acid sites,and subsequent La_(2.O_(3) loading reintroduces the weak acid *** a result,the HNO_(3)-La_(2.O_(3)-modified catalyst exhibits a slight increase in EB conversion and DEB yield in comparison with unmodified one,and meanwhile,it still maintains high m-DEB *** catalyst after acid treatment achieves higher catalytic stability besides maintaining the high alkylation activity of EB with *** present study on the spherical nano-HZSM-5 zeolite and its modification catalyst with excellent alkylation ability provides new insights into the production of mDEB.

关键词： Zeolite Modification Alkylation reaction m-diethylbenzene Catalyst Fixed-bed

Supramolecular systems for bioapplications:recent research progress in china

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Science china Chemistry 2024年第5期67卷 1397-1441页

作者： yue-Yang {1. Xiao-Yong yu yu-Chen Pan Hang Yin Shuang Chao yujie Li He Ma Minzan Zuo Kun-Xu Teng Jun-Li Hou Yong Chen Dong-Sheng Guo Ruibing wang yuxin Pei Zhichao Pei {2.-Fei Xu Xiao-yu Hu Chunju Li Qing-Zheng Yang Leyong wang yu {1. Zhan-Ting Li State Key Laboratory of Organometallic Chemistry Key Laboratory of Synthetic and Self-Assembly Chemistry for Organic Functional MoleculesShanghai Institute of Organic ChemistryChinese Academy of SciencesUniversity of Chinese Academy of SciencesShanghai 200032China Department of Chemistry Fudan UniversityShanghai 200438China College of Chemistry State Key Laboratory of Elemento-Organic ChemistryCollaborative Innovation Center of Chemical Science and EngineeringNankai UniversityTianjin 300071China State Key Laboratory of Quality Research in Chinese Medicine Institute of Chinese Medical SciencesUniversity of MacaoMacao 999078China College of Chemistry&Pharmacy Northwest A&F UniversityYangling 712100China Key Lab of Organic Optoelectronics&Molecular Engineering Department of ChemistryTsinghua UniversityBeijing 100084China College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 211106China Key Laboratory of Radiopharmaceuticals Ministry of EducationCollege of ChemistryBeijing Normal UniversityBeijing 100875China Tianjin Key Laboratory of Structure and Performance for Functional Molecules College of ChemistryTianjin Normal UniversityTianjin 300387China State Key Laboratory of Analytical Chemistry for Life Science Jiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

Supramolecular systems feature dynamic,reversible and stimuli-responsive characteristics,which are not easily achieved by molecular *** last decade has witnessed tremendous advances in the investigations of supramolecular systems for various bioapplications,which include drug delivery,anticancer therapy,antibacterial therapy,photodynamic therapy,photothermal therapy,combination therapy,antidotes for residual drugs or toxins,and bioimaging and ***-guest chemistry has played a key role in the development of such bioactive supramolecular systems,and natural macrocycles(such as cyclodextrins),synthetic macrocycles(such as calixarenes,cucurbit[n]urils,and pillararenes),and porous framework polymers(such as supramolecular organic frameworks and flexible organic frameworks)have been most successfully used as hosts to build different kinds of host-guest systems for attaining designed *** self-assembly of rationally designed amphiphilic molecules,macromolecules and polymers represent another important approach for the construction of supramolecular architectures with advanced *** this review,we summarize the important contributions made by Chinese researchers in this field,with emphasis on those reported in the past five years.

关键词： host-guest chemistry drug delivery anticancer and antibacterial photodynamic therapy photothermal therapy antidote transmembrane channel bioimaging and biosensing

Genome assembly of autotetraploid Actinidia arguta highlights adaptive evolution and enables dissection of important economic traits

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Plant Communications 2024年第6期5卷 173-192页

作者： Xue-Mei Lu Xiao-Fen yu Guo-Qiang Li Ming-Hao Qu Huan {1. Chuang liu yu-Ping Man Xiao-Han {2. Mu-Zi Li Jian {1. Qi-Qi Chen Rui Lei Cheng-Cheng Zhao yun-Qiu Zhou Zheng-{1. {2. Zuo-Zhou Li Shang Zheng Chang Dong Bai-Lin {1. Yan-Xiang Sun Hui-Qin Zhang Jie-Wei Li Quan-Hui Mo Ying Zhang Xin Lou Hai-Xu Peng Ya-Ting Yi He-Xin {1. Xiu-Jun Zhang Yi-Bo {1. Dan {1. Li Li Qiong Zhang Wen-Xia {1. Yongbo liu Lei Gao Jin-Hu Wu Yan-Chang {1. CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture Wuhan Botanical GardenChinese Academy of SciencesWuhanHubeiChina Key Laboratory of Western china’s Environmental Systems(Ministry of Education) College of Earth and Environmental SciencesLanzhou UniversityLanzhouGansuChina College of Life Sciences University of Chinese Academy of SciencesBeijingChina Wuhan Frasergen Bioinformatics Co. LtdWuhanHubeiChina Institute of Soil and Fertilizer Anhui Academy of Agricultural SciencesHefeiChina College of Agricultural Sciences Xichang UniversityXichangSichuanChina Department of Horticulture Heilongjiang Academy of Agricultural SciencesHarbinHeilongjiangChina College of Life Sciences Langfang Normal UniversityLangfangHebeiChina Institute of Horticulture Zhejiang Academy of Agricultural SciencesHangzhouZhejiangChina Guangxi Institute of Botany Chinese Academy of SciencesGuilinGuangxiChina Xi’an Botanical Garden of Shaanxi Province Institute of Botany of Shaanxi ProvinceXi’anShaanxiChina Institute of Modern Agricultural Research Dalian UniversityDalianLiaoningChina Bioinformatics Center College of Plant Science and TechnologyBeijing University of AgricultureBeijingChina College of Agriculture Eastern Liaoning UniversityDandongLiaoningChina Dalian Institute of Chemical Physics Chinese Academy of SciencesDalianLiaoningChina State Environmental Protection Key Laboratory of Regional Eco-process and Function Assessment Chinese Research Academy of Environmental SciencesBeijingChina Hubei Hongshan Laboratory WuhanHubeiChina The New Zealand Institute for Plant and Food Research Limited AucklandNew Zealand

Actinidia arguta,the most widely distributed Actinidia species and the second cultivated species in the genus,can be distinguished from the currently cultivated Actinidia chinensis on the basis of its small and smooth fruit,rapid softening,and excellent cold *** evolution of tetraploid Actinidia species and the genetic basis of their important agronomic traits are still ***,we generated a chromosome-scale genome assembly of an autotetraploid male *** *** genome assembly was 2.77 Gb in length with a contig N50 of 9.97 Mb and was anchored onto 1.6 *** and clustering of 1.1.geographically representative accessions showed that they could be divided into two geographic groups,Southern and Northern,which first diverged 1.0}9 million years *** underwent two prominent expansions and one demographic bottleneck from the midPleistocene climate transition to the late *** genomics studies using paleoclimate data enabled us to discern the evolution of the species’adaptation to different historical *** genes(AaCEL1.AaPME1.and AaDOF1.related to flesh softening were identified by multi-omics analysis,and their ability to accelerate flesh softening was verified through transient expression assays.A set of genes that characteristically regulate sexual dimorphism located on the sex chromosome(Chr3)or autosomal chromosomes showed biased expression during stamen or carpel *** chromosome-level assembly of the autotetraploid *** genome and the genes related to important agronomic traits will facilitate future functional genomics research and improvement of ***.

关键词： kiwiberry dioecism adaptive evolution paleoclimate GEA rapid softening

Chlorinated Thiazole-Based Low-Cost Polymer Donors for High Efficiency Binary and Ternary Organic Solar Cells

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CCS Chemistry 2024年第7期6卷 1757-1766页

作者： Hao Lu Hang wang Guang{1. Ran Wenlong {1. Hao Huang Xiaolin jiang Yahui {1. Xinjun Xu Zhishan Bo College of Materials Science and Engineering Qingdao UniversityQingdao 266071 College of Textiles&Clothing State Key Laboratory of Bio-Fibers and Eco-TextilesQingdao UniversityQingdao 266071 beijing Key Laboratory of Energy Conversion and Storage Materials College of ChemistryBeijing Normal UniversityBeijing 100875 Department of Physics and Applied Optics beijing Area Major Laboratory Beijing Normal UniversityBeijing 100875

In this work,novel D-A alternating polymers(PJ-1.PJ-2.and PJ-3)with chlorinated benzodithiophene and chlorinated thiazole units were synthesized via gradual *** polymers could be obtained readily through a few concise synthesis *** them,PJ-1.displayed desirable properties including energy levels,crystallinity,and charge transport *** binary and ternary organic solar cells(OSCs)fabricated based on PJ-1.displayed significant power conversion efficiency(PCE)of 1..02.and 1..1.0},respectively,placing them among the highest reported for ternary ***,the PJ1.based devices also showcased one of the highest figure-of-merit values,indicating their promising potential for future *** study offers valuable insights and supports the development of costeffective and high-performance polymer donors for the generation of OSCs.

关键词： organic solar cells low-cost donor high efficiency low energy loss ternary blend strategy