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Chinese Journal of Chemistry 2019年第8期37卷 786-792页

作者： Xinxin Zheng Guozhu zhang dayong zhang Institute of Pharmaceutical Science China Pharmaceutical UniversityNanjingJiangsu 210009China State Key Laboratory of Organometallic Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryChinese Academy of Sciences345 Lingling RoadShanghai 200032China

Summary of main observation and conclusion An intermolecular [4+2] cycloaddition was realized through C-C bond cleavage in the presence of Rh(Ⅰ) *** selective ring opening of 2-alkylenecyciobutanols enables the generation of active alkenylrhodium species,which underwent smooth cross addition over alkynes and (E)-2-nitroethenylbenzene,leading to highly substituted all-carbon six-membered rings in a single step and in a complete atom economy.

关键词： presence ring step was

Asexual and sexual reproductive strategies in clonal plants

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Frontiers in Biology 2007年第3期2卷 256-262页

作者： zhang Yufen zhang dayong Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering and Institute of Ecology Beijing Normal UniversityBeijing 100875China

Most plants can reproduce both sexually and asexually(or vegetatively),and the balance between the two reproductive modes may vary widely between and within *** clonal growth may affect the evolution of life history traits in many ***,in some clonal species,sexual reproduction and sex ratio vary largely among *** in sexual reproduction may strongly affect plant’s adaptation to local environments and the evolution of the geographic ***,clonal growth can increase floral display,and thus pollinator attraction,while it may impose serious constraints and evolutionary challenges on plants through geitonogamy that may strongly influence pollen *** pollination can bring a cost to plant fitness through both female and male *** co-evolutionary interactions,therefore,may exist between the spatial structure and the mating behavior of clonal ***,a trade-off may exist between sexual reproduction and clonal *** allocation to the two reproduc-tive modes may depend on environmental conditions,com-petitive dominance,life span,and genetic *** different reproductive modes represent adaptive strategies for plants in different environments,we expect that most of the resources should be allocated to sexual reproduction in habitats with fluctuating environmental conditions and strong competition,while clonal growth should be dominant in stable *** we know little about the consequence of natural selection on the two reproductive modes and factors which control the balance of the two reproductive *** studies should investigate the reproductive strategies of clonal plants simultaneously from both sexual and asexual perspectives.

关键词： clonal growth variation of sexual reproduction clonal architecture mating system trade-off

Neutral theory in community ecology

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Frontiers in Biology 2008年第1期3卷 1-8页

作者： Shurong ZHOU dayong zhang MOE Key Lab for Biodiversity Science&Ecological Engineering Beijing Normal UniversityBeijing 100875China Laboratory of Arid Agroecology Lanzhou UniversityLanzhou 730000China

One of the central goals of community ecology is to understand the forces that maintain species diversity within *** traditional niche-assembly theory asserts that species live together in a community only when they differ from one another in resource *** this theory has some difficulties in explaining the diversity often observed in specie-rich communities such as tropical *** an alternative to the niche theory,Hubbell and other ecologists introduced a neutral *** argues that the number of species in a community is controlled by species extinction and immigration or speciation of new *** that all individuals of all species in a trophically similar com-munity are ecologically equivalent,Hubbell’s neutral theory predicts two important statistical *** is the asymptotic log-series distribution for the metacommunities under point mutation speciation,and the other is the zero-sum multinomial distribution for both local communities under dispersal limitation and metacommunities under random fission *** the niche-assembly theory,the neutral theory takes similarity in species and individuals as a starting point for investigating species *** on the fundamental processes of birth,death,dispersal and spe-ciation,the neutral theory provided the first mechanistic explanation of species abundance distribution commonly observed in natural *** the publication of the neutral theory,there has been much discussion about it,pro and *** this paper,we summarize recent progress in the assumption,prediction and speciation mode of the neutral theory,including progress in the theory itself,tests about the assumption of the theory,prediction and speciation mode at the metacommunity *** also suggest that the most important task in the future is to bridge the niche-assembly theory and the neutral theory,and to add species differences to the neutral theory and more stochasticity to the ni

关键词： community neutral theory niche theory species diversity

Effects of dynamic recrystallization in extruded and compressed AZ31 magnesium alloy

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Acta Metallurgica Sinica(English Letters) 2010年第5期23卷 334-342页

作者： Xiaohui FAN Weiqin TANG Shaorui zhang dayong LI Yinghong PENG School of Mechanical Engineering Shanghai Jiao Tong University Shanghai 200240 China

Commercial AZ31 billets were extruded to round rods at three extrusion velocities of 0.8 m/min, 1.4 m/min and 2.2 m/min, at 643 K, 673 K and 703 K, respectively. The microstructure and texture evolution at different conditions were investigated by optical microscopy （OM） and electron backscattered diffraction （EBSD） techniques. The average grain size is reduced significantly after the hot extrusion, and the microstructure is obviously inhomogeneous due to dynamic recrystallization, which is confirmed by uni-axial compression experiments at elevated temperatures with different strain rates. The uni-axial compression leads to a fibre texture, and {110}010 texture is the major texture in extruded rods due to non-basal slip. As the extrusion temperature is elevated, the main texture becomes weak and other texture components appear.

关键词： AZ31 Extrusion Dynamic recrystallization Microstructure Stress-strain Texture

Control of vertical phase separation in high performance non-fullerene organic solar cell by introducing oscillating stratification preprocessing

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Nano Research 2021年第5期14卷 1319-1325页

作者： dayong zhang Pu Fan Jinyu Shi Yifan Zheng Jian Zhong Junsheng Yu State Key Laboratory of Electronic Thin Films and Integrated Devices School of Optoelectronic Science and EngineeringUniversity of Electronic Science and Technology of ChinaChengdu610054China Shanghai Institute of Optics and Fine Mechanics Chinese Academy of SciencesShanghai201800China

Non-fullerene organic solar cell(NFOSC)has attracted tremendous attention due to their great potential for commercial *** improve its power conversion efficiency(PCE),generally,sequential solution deposition(SSD)methods have been employed to construct the graded vertical phase separation(VPS)of the bulk-heterojunction(BHJ)active layer for efficient exciton separation and charge ***,a variety of orthogonal solvents used in the SSD may lead to the unpredicted change in the BHJ morphology and introduce additional defects inside the BHJ bulk thus complicate the fabrication ***,a simple oscillating stratification preprocessing(OSP)is developed to facilitate the formation of graded VPS among the BHJ *** a result,a significant improvement is obtained in PCE from 10.96%to 12.03%,which is the highest value reported among PBDB-T:ITIC based NFOSC.

关键词： oscillating stratification preprocessing graded vertical phase separation non-fullerene organic solar cells high performance sequential solution deposition

New Ligands for Copper-Catalyzed C-N Coupling Reactions at Gentle Temperature

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Chinese Journal of Chemistry 2014年第8期32卷 685-688页

作者： Jinyue Su Yatao Qiu Sheng Jiang dayong zhang Center of Drug Discovery China Pharmaceutical UniversityNanjingJiangsu 210009China Laboratory of Medicinal Chemistry Guangzhou Institute of Biomedicine and HealthGuangzhouGuangdong 510530China

Pyridin-2-ol-N-oxide was designed as an efficient ligand for the coupling reaction of aryl iodides,aryl bromides and aryl chlorides,respectively,with primary amines,cyclic secondary amines or N-containing heterocycles at room or moderate *** catalytic system showed great functional groups tolerance and excellent selective reactivity.

关键词： C-N coupling reactions copper corss-coupling pyridin-2-ol-N-oxide Ullmann reaction

Mining elite loci and candidate genes for root morphology-related traits at the seedling stage by genome-wide association studies in upland cotton(Gossypium hirsutum L.)

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Journal of Integrative Agriculture 2024年第10期23卷 3406-3418页

作者： Huaxiang Wu Xiaohui Song Muhammad Waqas-Amjid Chuan Chen dayong zhang Wangzhen Guo State Key Laboratory of Crop Genetics&Germplasm Enhancement and Utilization/Engineering Research Center of Cotton Germplasm Enhancement and Application Ministry of Education/Nanjing Agricultural UniversityNanjing 210095China

Root system architecture plays an essential role in water and nutrient acquisition in plants,and it is significantly involved in plant adaptations to various environmental *** this study,a panel of 242 cotton accessions was collected to investigate six root morphological traits at the seedling stage,including main root length(MRL),root fresh weight(RFW),total root length(TRL),root surface area(RSA),root volume(RV),and root average diameter(AvgD).The correlation analysis of the six root morphological traits revealed strong positive correlations of TRL with RSA,as well as RV with RSA and AvgD,whereas a significant negative correlation was found between TRL and ***,a genome-wide association study(GWAS)was performed using the root phenotypic and genotypic data reported previously for the 242 accessions using 56,010 single nucleotide polymorphisms(SNPs)from the CottonSNP80K array.A total of 41 quantitative trait loci(QTLs)were identified,including nine for MRL,six for RFW,nine for TRL,12 for RSA,12 for RV and two for *** them,eight QTLs were repeatedly detected in two or more *** these results with a transcriptome analysis,we identified 17 candidate genes with high transcript values of transcripts per million(TPM)≥30 in the ***,we functionally verified the candidate gene GH_D05G2106,which encodes a WPP domain protein 2in root development.A virus-induced gene silencing(VIGS)assay showed that knocking down GH_D05G2106significantly inhibited root development in cotton,indicating its positive role in root system architecture ***,these results provide a theoretical basis and candidate genes for future studies on cotton root developmental biology and root-related cotton breeding.

关键词： cotton root-morphology traits quantitative trait loci candidate genes GWAS

Suppressing a mitochondrial calcium uniporter activates the calcium signaling pathway and promotes cell elongation in cotton

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The Crop Journal 2024年第2期12卷 411-421页

作者： Yujia Duan Xiaoguang Shang Ruiping Tian Weixi Li Xiaohui Song dayong zhang Wangzhen Guo State Key Laboratory of Crop Genetics&Germplasm Enhancement and Utilization Nanjing Agricultural UniversityNanjing 210095JiangsuChina Engineering Research Center of Ministry of Education for Cotton Germplasm Enhancement and Application Nanjing Agricultural UniversityNanjing 210095JiangsuChina

Mitochondrial calcium uniporter(MCU)is a conserved calcium ion(Ca^(2+))transporter in the mitochondrial inner membrane of eukaryotic *** MCU proteins regulate Ca^(2+)flow and modulate plant cell development remain largely ***,we identified the gene GhMCU4 encoding a MCU protein that negatively regulates plant development and fiber elongation in cotton(Gossypium hirsutum).GhMCU4expressed constitutively in various tissues with the higher transcripts in elongating fiber *** of GhMCU4 in cotton significantly elevated the plant height and root *** calcium signaling pathway was significantly activated and calcium sensor genes,including Ca^(2+)dependent modulator of interactor of constitutively active ROP(GhCMI1),calmodulin like protein(GhCML46),calciumdependent protein kinases(GhCPKs),calcineurin B-like protein(GhCBLs),and CBL-interacting protein kinases(GhCIPKs),were dramatically upregulated in GhMCU4-silenced *** processes were preferentially enriched,and genes related to regulation of transcription were upregulated in GhMCU4-silenced *** contents of Ca^(2+)and H_(2)O_(2)were significantly increased in roots and leaves of GhMCU4-silenced *** length and Ca^(2+)and H_(2)O_(2)contents in fibers were significantly increased in GhMCU4-silenced *** study indicated that GhMCU4 plays a negative role in regulating cell elongation in cotton,thus expanding understanding in the role of MCU proteins in plant growth and development.

关键词： Calcium signaling Hydrogen peroxide Metabolic processed Gossypium hirsutum

Ice-Induced Vibrational Response of Single-Pile Offshore Wind-Turbine Foundations

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Fluid Dynamics & Materials Processing 2024年第3期20卷 625-639页

作者： Zhoujie Zhu Gang Wang Qingquan Liu Guojun Wang Rui Dong dayong zhang Department of Renewable Energy Engineering PowerChina Huadong Engineering Corporation LimitedHangzhou311122China School of Ocean Science and Technology Dalian University of TechnologyPanjin124221China Ningbo Institute of Dalian University of Technology Ningbo315000China

Important challenges must be addressed to make wind turbines sustainable renewable energy sources.A typical problem concerns the design of the *** the pile diameter is larger than that of the jacket platform,traditional mechanical models cannot be *** this study,relying on the seabed soil data of an offshore wind farm,the m-method and the equivalent embedded method are used to address the single-pile wind turbine foundation problem for different pile *** approach to determine the equivalent pile length is also proposed *** results provide evidence for the effectiveness and reliability of the model based on the equivalent embedded method.

关键词： Wind turbine ice-induced vibration dynamic response equivalent embedded method

高原双源动力集中型动车组网络关键技术及应用

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中国铁道科学 2023年第4期44卷 166-176页

作者：张大勇中国国家铁路集团有限公司科技和信息化部北京100084

高原环境下电气化与非电气化区间的跨线运营,对动力集中型动车组的多动力形式融合运用及不同类型动力车间、动力车与拖车间的互联互通互控、各系统间的信息交互和车载网络系统的稳定性、可用性、可靠性提出了更高的要求。针对高原双源... 详细信息

高原环境下电气化与非电气化区间的跨线运营,对动力集中型动车组的多动力形式融合运用及不同类型动力车间、动力车与拖车间的互联互通互控、各系统间的信息交互和车载网络系统的稳定性、可用性、可靠性提出了更高的要求。针对高原双源动力集中动车组动力源的多样性和安全监控的综合性,从网络传输、互联互通互控、自救援能力提升、安全监测数据融合方面,研究该动车组网络系统的关键技术;在进行动力车与拖车的网络控制系统架构设计的基础上,从动力车网络初运行控制技术、互联互通互控技术、长大隧道条件下自救援技术和综合安全监控技术等方面,优化设计车载网络通信架构,提出不同动力主体下混合牵引、内燃、电力模式的切换控制、整车主动式压力波的一体化控制、内燃动力自救援控制及内燃模式下列车供电系统强行投入控制策略;为实现多动力主体协同的安全监控数据融合,构建动车组车载综合安全监测一体化平台,并进行功能和性能验证。结果表明:高原双源动力集中动车组网络关键技术能够满足恶劣环境及复杂应用场景的需求,研究结论可为后续双源动力集中动车组多种组合方式的推广和应用提供技术支撑和应用保证。

关键词：高原双源动力集中动车组车载网络系统互联互通互控综合安全监测长大隧道自救援