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Sr-Nd isotopic characteristics and their significance in provenance tracing of detrital sediment in major rivers and marginal seas of eastern China

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Science China Earth Sciences 2025年

作者： Xiaobao GAO Chao LI Zhifei DUAN yulong guo Shouye YANG State Key Laboratory of Marine Geology Tongji University

Sr-Nd isotopes are widely utilized as reliable tracers in sediment provenance *** this study,we compiled 304Sr and 335 Nd isotope data of fine-grained surface sediments collected from major rivers in eastern China,including the Huanghe River,Changjiang River,southeastern coastal rivers,and rivers in Taiwan Island,as well as from marginal seas （Yellow Sea and East China Sea） and the Okinawa *** comprehensive dataset allowed us to examine the spatial distribution patterns of these isotopes and their implications for provenance *** variations of εNd values in the sediments in Changjiang and Huanghe Basins primarily reflect the diversity of sediment sources,whereas the87Sr/86Sr ratios are influenced by both grain size and source ***,the reduction in87Sr/86Sr ratios observed in the middle and lower Changjiang River is attributed to the inputs of sources characterized by distinct87Sr/86Sr signatures beyond mere grain size *** the southeastern coastal and Taiwan rivers,sediments in the tidal reaches of the Jiao River exhibit hybrid characteristics,a mix of Changjiang-derived sediment and those originating from local ***,the Min River and Jiulong River sediments predominantly reflect local sources,with minimal influence from the Changjiang *** significant isotopic variation of Sr-Nd isotopic characteristics observed between riverine sediments on the eastern and western sides of Taiwan Island underscores the diverse provenance heterogeneity of source rocks in the *** the marginal seas,our data indicates that the surface sediments in the central mud area of the South Yellow Sea and the southern Yellow Sea are predominantly sourced from the Changjiang River catchment,potentially augmented by inputs from Korean *** inner shelf sediments of the East China Sea are primarily influenced by Changjiang River inputs,whereas rivers in eastern Taiwan Island contribute to the sediments on the middle and

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Variation of Out-of-Plane Constraint and Its Effects on Fracture

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上海交通大学学报 2004年第Z2期38卷 212-216页

作者： Fei Xu yulong Li Wanlin guo Department of Mechanical Engineering Tokyo University of Science Noda2788510 Japan School of Aeronautics Northwestern Polytechnical University Xi''an710072 P. R. China School of Aeronautics Northwestern Polytechnical University Xi''an710072 P. R. China School of Aeronautics and Astronauts Nanjing University of Aeronautics and AstronautsNaniing210016 P.R.China

The limitations of using one-parameter to describe the crack-tip fields have prompted investigators to consider better descriptions of the crack tip fields. The two-parameter descriptions, such as J-Q theory, have been an important development in this field. But under the consideration of plane strain and three-dimensional problem, the effects of the out-of-plane stress can not be neglected In this paper, effects of the in-plane constraint as well as the out-of-plane constraint are studied by aid of the finite element method on the plane strain condition. It is obvious that both the in-plane constraint (Q factor) and the out-of-plane constraint (Tz = σzz/(σxx + σyy) ) affect the crack tip *** important features of the out-of-plane constraint are described out based on the simulation results. At the end of this paper, a three-parameter formulation is proposed, in which both the in-plane constraint and the out-of-plane constraint are considered. Comparing with the results of the FEM numerical simulation, the three-parameter description can provide a better prediction near the crack tip.

关键词： in-plane constraint out-of-plane constraint three-parameter formulation crack tip field elastic-plastic

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The principle,application,and prospect of using the uranium comminution age to indicate the catchment erosion depth

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Science China Earth Sciences 2023年第7期66卷 1439-1449页

作者： Hongmin XU Chao LI Zhifei DUAN yulong guo Shouye YANG State Key Laboratory of Marine Geology Tongji UniversityShanghai 200092China School of Ocean and Earth Sciences Tongji UniversityShanghai 200092China

Catchment erosion not only shapes various landforms of the earth’s surface but also affects the rates of chemical weathering and CO_(2) absorption by controlling the exposure of rock fragments,and thus acts as a regulator of the global ***,studying the occurrence and controlling factors of catchment erosion can improve our understanding of topographic evolution and long-term climate *** paper introduces the“comminution age”method based on (^(234)U/^(238)U) of sediment detrital components and its applications to indicate the catchment erosion depth,which is widely applied to different depositional *** tectonically stable regions,where there is shallow erosion,the sediment output from the catchment is usually accompanied by a low (^(234)U/^(238)U).On the other hand,where there is deep erosion,the (^(234)U/^(238)U) of the downstream sediments is usually *** tectonically active regions,deep erosion is common,and the sediment erosion process is subject to rapid material transport,such as landslide-induced sediment *** the sediment exposure history is short,the (^(234)U/^(238)U) of the detrital components is close to 1,thus reaching“secular equilibrium”.The comminution age method is promising in terms of tracing catchment erosion depths at the orbital ***,this method is also sensitive to the erosion changes caused by rapid climate changes and human activities.

关键词： Catchment scale Erosion depth Comminution age (^(234)U/^(238)U)

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Sediment recycling and indication of weathering proxies

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Acta Geochimica 2017年第3期36卷 498-501页

作者： yulong guo Shouye Yang Chao Li Lei Bi Yun Zhao State Key Laboratory of Marine Geology Tongji University Laboratory for Marine Geology Qingdao National Laboratory for Marine Science and Technology

As a result of recycling, the mineralogical and chemical compositions of riverine sediments may reflect the combined effects of the present-day weathering regime as well as previous weathering and diagenetic alteration history. River sediments can be interpreted as a mixture of non-weathered bedrock—of igneous, metamorphic, or sedimentary origin—and solids formed by the modern weathering system. The correlation between the weathering proxies chemical index of alteration and weathering index of Parker offers an approach to distinguish fine suspended particles, coarse bedload sediments, and recycled sediments under the influence of quartz dilution. Recycling of cation-depleted source rocks formed during past geological weathering episodes may have great impacts on the weathering indices of sediments from the Changjiang(Yangzte) and Zhuoshui Rivers. Special caution is required when using chemical weathering indices to investigate the intensity of chemical weathering registered in fluvial sediments. To minimize the effect of hydrodynamic sorting or sediment recycling, we suggest that the fine sediments(*** particles and ﹤2 lm fractions of bedload sediments) in rivers better reflect the average of weatheredcrust in catchments and the terrigenous end-member in marginal seas.

关键词： River sediments Weathering indices Sediment recycling Source-to-sink

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CRISPR/Cas9-mediated targeted mutation reveals a role for AN4 rather than DPL in regulating venation formation in the corolla tube of Petunia hybrida

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Horticulture Research 2021年第1期8卷 1798-1806页

作者： Bin Zhang Xiaojing Xu Renwei Huang Sha Yang Mingyang Li yulong guo Chongqing Engineering Research Center for Floriculture Key Laboratory of Horticulture Science for Southern Mountainous RegionsMinistry of EducationCollege of Horticulture and Landscape ArchitectureSouthwest University400716 ChongqingChina College of Agriculture Guizhou University550025 GuiyangGuizhouChina Sichuan Provincial Key Laboratory for Development and Utilization of Characteristic Horticultural Biological Resources College of Chemistry and Life SciencesChengdu Normal University611130 ChengduChina

Venation is a common anthocyanin pattern displayed in flowers that confers important ornamental traits to *** anthocyanin-related R2R3-MYB transcription factor,DPL,has been proposed to regulate corolla tube venation in petunia ***,however,we provide evidence redefining the role of DPL in petunia.A CRISPR/Cas9-mediated mutation of DPL resulted in the absence of the vein-associated anthocyanin pattern above the abaxial surface of the flower bud,but not corolla tube venation,thus indicating that DPL did not regulate the formation of corolla tube ***,quantitative real-time PCR analysis demonstrated that the spatiotemporal expression pattern of another R2R3-MYB gene,AN4,coincided with the formation of corolla tube venation in ***,overexpression of AN4 promoted anthocyanin accumulation by increasing the expression of anthocyanin biosynthesis ***/Cas9-mediated mutation of AN4 led to an absence of corolla tube venation,suggesting that this gene in fact determines this key plant *** together,the results presented here redefine the prime regulator of corolla tube venation,paving the way for further studies on the molecular mechanisms underlying the various venation patterns in petunia.

关键词： CRISPR/Cas9 pattern flowers

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A Wind Tunnel Experimental Study on the Wake Characteristics of a Horizontal Axis Wind Turbine

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Journal of Thermal Science 2025年第1期34卷 145-158页

作者： guo Xingduo LI Yinran LI Rennian MA yulong WEI Kui College of Energy and Power Engineering Lanzhou University of Technology Key Laboratory of Fluid Machinery and Systems Gansu Provincial Technology Centre for Wind Turbines

The characteristics of wind turbine wakes are influenced by multiple factors,including the atmospheric boundary layer(ABL) wind and wind turbine operating conditions(e.g.,tip speed ratio and yaw angle).In this study,two types of ABL winds with different velocity gradients and turbulence intensities are generated in a wind tunnel through configurations of spires,baffles,and various numbers of roughness elements.A wind turbine with a rotor diameter of 0.8 m and a hub height of 0.6 m is tested under varying tip speed ratios,yaw angles,and ABL wind *** results indicate that the streamwise velocity deficit in the near-wake region becomes more pronounced with an increase in the tip speed ratio,while the far-wake velocity deficit remains largely unaffected by changes in the tip speed *** the yaw angle increases,the wake deflection becomes more prominent and the wake narrows;the offset of the wake center at various downstream positions grows linearly,reaching a maximum value of approximately half the rotor ***,the turbulence level and influence range in the wake region are reduced when the turbine is *** ABL wind conditions,high turbulence intensity in the incoming flow accelerates wake recovery,and the Reynolds stress at different lateral positions tends to become consistent with increasing longitudinal ***,turbulence has a significant impact on the meandering characteristics of the wind turbine wake,with greater fluctuations in the wake center observed under higher turbulence ***,this study provides insights that could inform the optimal operation of wind farms.

关键词： horizontal axis wind turbine turbulence wind tunnel experiment wind turbine wake

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New insights into eutrophication management:Importance of temperature and water residence time

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Journal of Environmental Sciences 2022年第1期34卷 229-239页

作者： Feng Zhao Xu Zhan Hai Xu Guangwei Zhu Wei Zou Mengyuan Zhu Lijuan Kang yulong guo Xingchen Zhao Zicong Wang Wei Tang State Key Laboratory of Lake and Environment Nanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing 210008China University of Chinese Academy of Sciences Beijing 100049China School of Environmental and Civil Engineering Jiangnan UniversityWuxi 214122China

Eutrophication and harmful cyanobacterial blooms threaten water resources all over the *** is a great controversy about controlling only phosphorus or controlling both nitrogen and phosphorus in the management of lake *** primary argument against the dual nutrients control of eutrophication is that nitrogen fixation can compensate the nitrogen ***,it is of great necessary to study the factors that can significantly affect the nitrogen *** to the difference of climate and human influence,the water quality of different lakes(such as water temperature,N:P ratio and water residence time)is also quite *** studies have reported that the low N:P ratio can intensify the nitrogen fixation ***,the effects of temperature and water residence time on the nitrogen fixation remain ***,30 shallows freshwater lakes in the eastern plain of China were selected to measure dissolved N_(2) and Ar concentrations through N_(2):Ar method using a membrane inlet mass spectrometer to quantify the nitrogen fixation capacities and investigate whether the temperature and water residence time have a great impact on nitrogen *** results have shown that the short lake water residence time can severely inhibit the nitrogen fixation capacities through inhibiting the growth of nitrogenfixing cyanobacteria,changing the N:P ratio and resuspending the solids from ***,lakes with low water temperature also have a low nitrogen fixation capacity,suggesting that controlling nitrogen in such lakes is feasible if the growth of cyanobacteria is limited by nitrogen.

关键词： Eutrophication N_(2):Ar method Temperature N:P ratio Lake water residence time

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1961-2020年赣江流域月尺度实际蒸发模拟及归因分析

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水土保持研究 2025年第1期32卷 195-202页

作者：姬广兴刘智培高红凯陈伟强黄珺嫦张亚丽郭宇龙陈轶楠河南农业大学资源与环境学院郑州450046 华东师范大学地理科学学院上海200241

[目的]探究赣江流域月时间尺度实际蒸发的变化规律和分配特征以及不同因素对实际蒸发量的贡献量,为生态环境保护和水资源高效利用提供理论依据。[方法]基于赣江流域外洲水文站1961-2020年径流量数据,结合Mann-Kendall突变检验法和Pettit... 详细信息

[目的]探究赣江流域月时间尺度实际蒸发的变化规律和分配特征以及不同因素对实际蒸发量的贡献量,为生态环境保护和水资源高效利用提供理论依据。[方法]基于赣江流域外洲水文站1961-2020年径流量数据,结合Mann-Kendall突变检验法和Pettitt突变点检验法确定径流突变年份。其次利用ABCD水文模拟赣江流域基准期和突变期径流变化过程,计算得出月尺度实际蒸发量。然后利用去趋势预置白趋势检验法(TFPW-MK)分析实际蒸发的变化趋势和年内分布特征。最后采用月尺度Budyko模型对实际蒸发量变化进行归因分析。[结果](1)径流突变年份为1991年。(2)赣江流域2月、3月、4月、6月、9月的实际蒸发量呈现上升趋势,其余月份实际蒸发为下降趋势。其中2月、3月的实际蒸发量显著上升(p<0.05)。(3)赣江流域月尺度实际蒸发量呈现“单峰型”分布,在7月附近达到最大值。(4)气候变化会导致各月实际蒸发量的增加,人类活动会导致各月实际蒸发量减少。[结论]赣江流域实际蒸发量呈现先增大后减少的趋势,气候变化对实际蒸发量的贡献表现为正作用。人类活动对实际蒸发量变化表现为负作用。

关键词：实际蒸发量变化气候变化人类活动 ABCD模型月尺度Budyko模型

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An Improvement on the Protein Extraction Procedure from Eggshell Membrane

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明胶科学与技术 2010年第4期30卷 181-182页

作者： Peng Ruo- ting guo yulong Vienna lntemational School （Strasse der Menschenrechte 1 1220 Vienna Austria） Beijing Jiuzhoulongling Hi - tech Env. Prot. Mat. Company

1 IntroductionCollagen is a frequently occurring protein found in poultry, livestock and human body, esp. in the hair, skin, bone cartilage, tendon and so on. It forms the strongly insoluble fibers and serves as connective tissue supporting materials. Nowadays it became one of the most important raw materials of bio-engineering materials which are widely used in various fields including

关键词：蛋白质提取方法隔膜原料

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Isolation and characterization of resistance and defense gene analogs in cotton (Gossypium barbadense L.)

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Science China Life Sciences 2006年第6期49卷 530-542页

作者： GAO yulong,guo Wangzhen,WANG Lei & ZHANG Tianzhen National Key Laboratory of Crop Genetics and Germplasm Enhancement,Nanjing Agricultural University,Nanjing 210095,China National Key Laboratory of Crop Genetics and Germplasm Enhancement Nanjing Agricultural University Nanjing China

Plant disease resistance gene (R gene) and defense response gene encode some con-served motifs. In the present work,a PCR strategy was used to clone resistance gene analogs (RGAs) and defense gene analogs (DGAs) from Sea-island cotton variety Hai7124 using oligonucleotide primers based on the nucleotide-binding site (NBS) and serine/threonine kinase (STK) in the R-gene and pathogenesis-related proteins of class 2 (PR2) of defense response gene. 79 NBS sequences,21 STK sequences and 11 DGAs were cloned from disease-resistance cotton. Phylogenic analysis of 79 NBS-RGAs and NBS-RGAs nucleotide sequences of cotton already deposited in GenBank identified one new sub-cluster. The deduced amino acid sequences of NBS-RGAs and STK-RGAs were divided into two distinct groups respectively: Toll/Interleukin-1 receptor (TIR) group and non-TIR group,A group and B group. The expression of RGAs and DGAs having consecutive open reading frame (ORF) was also investigated and it was found that 6 NBS-RGAs and 1 STK-RGA were induced,and 1 DGA was up-regulated by infection of Verticillium dahliae strain VD8. 4 TIR-NBS-RGAs and 4 non-TIR-NBS-RGAs were arbitrarily used as probes for Southern-blotting. There existed 2-10 blotted bands. In addition,since three non-TIR-NBS-RGAs have the same hybridization pattern,we conjecture that these three RGAs form a cluster distribution in the genome.

关键词： cotton resistance gene analogs (RGAs) defense gene analogs (DGAs).

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