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Permian ridge subduction-related magmatism in the Chinese Altai: Insights from geochronology and geochemistry of the Jiangjunshan pluton

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Journal of Earth science 2024年

作者： Shi-Heng Bai Ru-Xiong Lei Matthew J.Brzozowski Zhenhua Wang Wei Wang Chang-Zhi Wu Laboratory of Mineralization and Dynamics， School of Earth science and resources， Chang'an University Xinjiang natural resources and Ecological Environment Research Center

The Chinese Altai is an important constituent of the Central Asian Orogenic Belt， a prominent Phanerozoic accretionary orogenic belt. Oceanic-continental subduction processes during the Cambrian–Carboniferous and intracontinental extension from the Triassic onwards have been well constrained in the Chinese Altai， the southwestern portion of the CAOB. Characterizing the petrogenetic evolution of the Chinese Altai during the Permian has， therefore， been considered critical to enhancing our understanding of the tectonic transformations that occurred in this region. Despite this， the tectonic environment of the Chinese Altai during this period remains equivocal. To address this deficiency， this contribution characterizes the age of formation and geochemical composition of the Jiangjunshan pluton located in the southern portion of the Chinese Altai. Zircon U-Pb geochronology demonstrates that the gabbro and two-mica alkali feldspar granite， which comprise the main body of the Jiangjunshan pluton， formed at ca. 272 ± 3.5 and 272 ± 1.6 Ma， respectively. Geochemically， the gabbro is depleted in light rare earth elements （LREE）， has low Nb/Yb （0.39–0.46） and Ti/V （23.7–25.3） ratios， exhibits trace-element characteristics resembling normal mid-ocean ridge basalts （N-MORB）， but is depleted in Nb and Ta similar to island arc basalts. The depleted Hf and Nd isotope compositions (εHf（t） = +0.60 to +4.63， εNd（t） = +6.32 to +7.80) of the gabbro， coupled with the weak correlation between εNd（t） values and SiO2contents， suggest that the magma from which it crystallized was slightly contaminated by crustal material during its evolution. Based on the Sm， Yb， and La contents， it is inferred that the melt from which the gabbro crystallized originated from approximately 8–20% partial melting of spinel lherzolite mantle. The depleted Hf and Nd isotope compositions (εHf（t） = +6.81 to +9.10， εNd（t） = +0.79 to +1.45) of the granite， combined with petrographic observations （e.g.， absent of the

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Experimental study on the variation of optical remote sensing imaging characteristics of internal solitary waves with wind speed

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Journal of Oceanology and Limnology 2024年第2期42卷 408-420页

作者： Zhe CHANG Lina SUN Tengfei LIU Meng ZHANG Keda LIANG Junmin MENG Jing WANG School of Physics and Optoelectronic Engineering Ocean University of ChinaQingdao 266100China First Institute of Oceanography Ministry of Natural ResourcesQingdao 266061China Technology Innovation Center for Ocean Telemetry Ministry of Natural ResourcesQingdao 266061China

Optical remote sensing has been widely used to study internal solitary waves(ISWs).Wind speed has an important effect on ISW imaging of optical remote *** light and dark bands of ISWs cannot be observed by optical remote sensing when the wind is too *** relationship between the characteristics of ISWs bands in optical remote sensing images and the wind speed is still *** influence of wind speeds on the characteristics of the ISWs bands is investigated based on the physical simulation experiments with the wind speeds of 1.6,3.1,3.5,3.8,and 3.9 m/*** experimental results show that when the wind speed is 3.9 m/s,the ISWs bands cannot be observed in optical remote sensing images with the stratification of h_(1)∶h_(2)=7∶58,ρ_(1)∶ρ_(2)=1∶*** the wind speeds are 3.1,3.5,and 3.8 m/s,which is lower than 3.9 m/s,the ISWs bands can be obtained in the simulated optical remote sensing *** location of the band’s dark and light extremum and the band’s peak-to-peak spacing are almost not affected by wind ***-significant wind speeds can cause a greater gray difference of the light-dark *** provided a scientific basis for further understanding of ISW optical remote sensing imaging.

关键词： internal solitary wave(ISW) optical remote sensing wind speed characteristics of ISWs bands

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Tracing nitrate sources in one of the world's largest eutrophicated bays(Hangzhou Bay):insights from nitrogen and oxygen isotopes

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Acta Oceanologica Sinica 2024年第6期43卷 86-95页

作者： Zhi Yang Jianfang Chen Haiyan Jin Hongliang Li Zhongqiang Ji Yangjie Li Bin Wang Zhenyi Cao Qianna Chen Key Laboratory of Marine Ecosystem Dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China

Eutrophication caused by inputs of excess nitrogen(N) has become a serious environmental problem in Hangzhou Bay(China),but the sources of this nitrogen are not well *** this study,the August 2019 distributions of salinity,nutrients [nitrate(NO_(3)^(-)),nitrite,ammonium,and phosphate],and the stable isotopic composition of NO_(3)^(-)(δ^(15)N and δ^(18)O) were used to investigate sources of dissolved inorganic nitrogen(DIN) to Hangzhou B *** distributions of nitrate,salinity,and nitrate δ^(18)O indicate that the Qiantang River,the Changjiang River,and nearshore coastal waters may all contribute nitrate to the *** on the isotopic compositions of nitrate in these potential source waters and conservative mixing of nitrate in our study area,we suggest that the NO_(3)^(- )in Hangzhou B ay was likely derived mainly from soils,synthetic N fertilizer,and manure and ***-member modeling indicates that in the upper half of the bay,the Qiantang River was a very important DIN source,possibly contributing more than 50% of DIN in the bay head *** the lower half of the bay,DIN was sourced mainly from strongly intruding coastal *** coming directly from the Changjiang River made a relatively small contribution to Hangzhou Bay DIN in August 2019.

关键词： nitrogen isotopes oxygen isotopes nitrogen cycle nitrate sources Hangzhou Bay

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Asexual Reproduction of Aurelia coerulea Polyps in situ on Settling Plates in Jiaozhou Bay, China

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Journal of Ocean University of China 2024年第5期23卷 1371-1380页

作者： MI Tiezhu ZHU Jianbin ZHEN Yu WANG Guoshan WANG Jianyan Key Laboratory of Marine Environment and Ecology Ministry of Education College of Environmental Science and Engineering Ocean University of China Laboratory for Marine Ecology and Environmental science Qingdao Marine Science and Technology Center Frontiers science Center for Deep Ocean Multispheres and Earth System Ocean University of China National Marine Hazard Mitigation Service Ministry of Natural Resources department of Life sciences National Natural History Museum of China

Jellyfish blooms are increasingly prevalent coastal phenomena, with Aurelia coerulea being a significant contributor. The complex life history of jellyfish, featuring a sessile polyp stage, is a key factor in bloom formation, yet it is challenging to study in the field. This study aimed to describe the asexual reproduction of A. coerulea polyps in Jiaozhou Bay, China, and to assess their ability to form sedentary colonies and their relationship with environmental factors. Using settling plates, we observed polyps in situ and documented three asexual reproduction modes: budding, strobilation, and podocyst formation. Environmental parameters including temperature, salinity, dissolved oxygen(DO), chlorophyll a(Chl a), and the biomass of phytoplankton and zooplankton were monitored. Budding was the predominant reproductive method, featuring stolon budding in autumn and direct budding during the winter and spring seasons. Strobilation took place in the colder months, releasing ephyrae between April and May. Polyp abundance was positively correlated with seawater temperature and negatively correlated with DO concentration. Polyps at 1.0 m depth showed higher survivorship and proliferation over 8 months, whereas those at 2.0 m depth experienced a steady decline and died within 4 months. The study enhances our understanding of the life cycle and asexual reproduction strategies of A. coerulea polyps in the field, with implications for predicting and managing jellyfish blooms. The findings underscore the importance of temperature and DO in polyp survival and suggest that initial polyp population proliferation is crucial for long-term survival.

关键词： asexual reproduction budding jellyfish bloom polyps strobilation

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Water quality, habitat, and fish assemblage relationships in middle-order agriculture and forest streams of the Mississippi Alluvial Plain

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Ecological Processes 2024年第01期13卷 217-236页

作者： Matthew L.Skoog Michael A.Eggleton Yushun Chen department of Aquaculture and Fisheries University of Arkansas at Pine Bluff Minnesota department of natural resources State Key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences University of Chinese Academy of sciences

Background Agriculture has greatly influenced water quality, habitats, and fish assemblages in streams of the Mississippi Alluvial Plain(MAP) ecoregion. However, MAP streams have historically been understudied compared to streams in other agricultural regions of the USA. In this study, water quality, habitat, and fish assemblage composition were assessed seasonally(spring, summer, and fall) in eight representative MAP streams located across three U.S. states. The study design included four streams containing highly agricultural watersheds(herein termed “agriculture” streams) and four streams containing mostly forested watersheds(herein termed “forest” streams), which were intended to represent reference conditions for MAP *** In general, forest streams contained significantly better instream and riparian habitats than agriculture streams(P = 0.010–0.040) whereas agriculture streams contained significantly greater levels of primary nutrients(P < 0.001–0.010). Differences between agriculture and forest streams with respect to other physical and chemical variables were intermittent and season dependent. Fish assemblages in agriculture and forest streams were structured primarily along an environmental gradient reflecting instream habitat conditions, water nutrient concentrations, and benthic chlorophyll-a production. Structurally, fish assemblages in both stream types contained many regionally common species, though some species appeared to exhibit affinities for a particular stream type. Functionally, fish assemblages in agriculture streams contained more tolerant species, more omnivores, and fewer insectivores compared to forest stream assemblages, which were nearly all insectivores. Overall, one-third of the fish specimens collected in forest streams classified as intolerant *** Our results suggested that stream water quality, habitat, and fish assemblages differed between agriculture and forest streams in the MAP, with fish assemblages e

关键词： Agriculture Stream Land use Water quality Habitat Fish Multivariate statistics Mississippi Alluvial Plain

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The connection of phytoplankton biomass in the Marguerite Bay polynya of the western Antarctic Peninsula to the Southern Annular Mode

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Acta Oceanologica Sinica 2024年第1期43卷 35-47页

作者： Ning Jiang Zhaoru Zhang Ruifeng Zhang Chuning Wang Meng Zhou School of Oceanography Shanghai Jiao Tong UniversityShanghai 200240China Key Laboratory for Polar science Polar Research Institute of ChinaMinistry of Natural ResourcesShanghai 200136China

Antarctic coastal polynyas are biological hotspots in the Southern Ocean that support the abundance of hightrophic-level predators and are important for carbon cycling in the high-latitude *** this study,we examined the interannual variation of summertime phytoplankton biomass in the Marguerite Bay polynya(MBP)in the western Antarctic Peninsula area,and linked such variability to the Southern Annular Mode(SAM)that dominated the southern hemisphere extratropical climate *** satellite data,atmosphere reanalysis products and numerical simulations,we found that the interannual variation of summer chlorophyll-a(Chl-a)concentration in the MBP is significantly and negatively correlated with the spring SAM index,and weakly correlated with the summer SAM *** negative relation between summer Chl-a and spring SAM is due to weaker spring vertical mixing under a more positive SAM condition,which would inhibit the supply of iron from deep layers into the surface euphotic *** negative relation between spring mixing and spring SAM results from greater precipitation rate over the MBP region in positive SAM phase,which leads to lower salinity in the ocean surface *** coupled physical-biological mechanisms between SAM and phytoplankton biomass revealed in this study is important for us to predict the future variations of phytoplankton biomasses in Antarctic polynyas under climate change.

关键词： Marguerite Bay polynya phytoplankton biomass Southern Annular Mode mixed layer depth interannual variation

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Quantitative Identification of Delamination Damage in Composite Structure Based on Distributed Optical Fiber Sensors and Model Updating

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Structural Durability & Health Monitoring 2024年第6期18卷 785-803页

作者： Hao Xu Jing Wang Rubin Zhu Alfred Strauss Maosen Cao Zhanjun Wu School of Materials science and Engineering Dalian University of TechnologyDalian116000China School of Mechanics and Aerospace Engineering Dalian University of TechnologyDalian116000China department of Civil Engineering and natural Hazards University of Natural Resources and Life SciencesVienna1180Austria department of Engineering Mechanics Hohai UniversityNanjingChina

Delamination is a prevalent type of damage in composite laminate *** accumulation degrades structural performance and threatens the safety and integrity of *** study presents a method for the quantitative identification of delamination identification in composite materials,leveraging distributed optical fiber sensors and a model updating ***,a numerical analysis is performed to establish a parameterized finite element model of the composite ***,this model subsequently generates a database of strain responses corresponding to damage of varying sizes and *** radial basis function neural network surrogate model is then constructed based on the numerical simulation results and strain responses captured from the distributed fiber optic ***,a multi-island genetic algorithm is employed for global optimization to identify the size and location of the *** efficacy of the proposed method is validated through numerical examples and experiment studies,examining the correlations between damage location,damage size,and strain *** findings confirm that the model updating technique,in conjunction with distributed fiber optic sensors,can precisely identify delamination in composite structures.

关键词： Composite structures fiber optic sensor damage identification model updating surrogate model

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One stone three birds:Ni-catalyzed asymmetric allenylic substitution of allenic ethers,hydroalkylation of 1,3-enynes and double alkylation of enynyl ethers

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Chinese Chemical Letters 2024年第8期35卷 282-287页

作者： Zhirong Yang Shan Wang Ming Jiang Gengchen Li Long Li Fangzhi Peng Zhihui Shao Key Laboratory of Medicinal Chemistry for natural Resource Ministry of EducationSchool of Chemical Science and TechnologyYunnan Provincial Center for Research&Development of Natural Productsand State Key Laboratory for Conservation and Utilization of Bio-Resources in YunnanYunnan UniversityKunming 650091China

The development of low-cost,earth-abundant and environmentally benign transition metal catalysts,which can catalyze multiple different types of asymmetric reactions,is an important objective in mod-ern asymmetric *** we demonstrate that a chiral Ni/P-Phos catalyst achieves three types of asymmetric reactions:allenylic substitution of racemic allenic ethers,1,4-hydroalkylation of prochiral 1,3-enynes and double alkylation of newly designed enynyl ether *** methods complement each other and produce various axially chiral allene derivatives bearing a pyrazolidine-3,5-dione unit,which is widely present in drugs and biologically active molecules with versatile pharmacological activities.

关键词： Nickel Asymmetric catalysis Allenylic substitution Hydroalkylation Double alkylation Allene 1,3-Enyne Pyrazolidine-3,5-dione

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Applications and grants of the National natural science Foundation of China's General Program and Young Scientists Fund in immunology research:a 10-year review(2013–2022)

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science China(Life sciences) 2024年第6期67卷 1321-1324页

作者： Baoman Li Yanyan Tian Puyue Wang department of Life sciences National Natural Science Foundation of ChinaBeijing 100085China

Immunology,a biomedical discipline with an ancient history of maintaining thriving research vitality to date,refers to the study of the structure and function of the immune system of the body,the pathogenesis of immune-related diseases,immunological diagnoses,and prevention mechanisms(National natural science Foundation of China,2023).Immunological research is the foundation of research in biology,as well as basic and clinical medicine(Kubli et al.,2021).

关键词： prevention Foundation natural

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Three-dimensional thermohaline structure estimation derived from HY-2 satellite data over the Maritime Silk Road and its applications

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Acta Oceanologica Sinica 2024年第5期43卷 41-53页

作者： Zhiqiang Chen Xidong Wang Xiangyu Wu Yuan Cao Zikang He Dakui Wang Jian Chen Key Laboratory of Marine Hazards Forecasting Ministry of Natural ResourcesHohai UniversityNanjing 210024China Laboratory for Regional Oceanography and Numercial Modeling Qingdao Marine Science and Technology CenterQingdao 266061China National Marine Environmental Forecasting Center Ministry of Natural ResourcesBeijing 100081China Beijing Institute of Applied Meteorology Beijing 100029China

Estimated ocean subsurface fields derived from satellite observations provide potential data sources for operational marine environmental monitoring and prediction *** study employs a statistic regression reconstruction method,in combination with domestic autonomous sea surface height and sea surface temperature observations from the Haiyang-2(HY-2)satellite fusion data,to establish an operational quasi-realtime three-dimensional(3D)temperature and salinity products over the Maritime Silk *** products feature a daily temporal resolution and a spatial resolution of 0.25°×0.25°and exhibit stability and *** have demonstrated the accuracy of the reconstructed thermohaline fields in capturing the 3D thermohaline variations through comprehensive statistical evaluations,after comparing them against Argo observations and ocean analysis data from *** results illustrate that the reconstructed fields effectively represent seasonal variations in oceanic subsurface structures,along with structural changes resulting from mesoscale processes,and the upper ocean’s responses to tropical ***,the incorporation of HY-2 satellite observations notably enhances the accuracy of temperature and salinity reconstructions in the Northwest Pacific Ocean and marginally improves salinity reconstruction accuracy in the North Indian Ocean when compared to the World Ocean Atlas 2018 monthly climatology thermohaline *** a result,the reconstructed product holds promise for providing quasi-real-time 3D temperature and salinity field information to facilitate fast decisionmaking during emergencies,and also offers foundational thermohaline fields for operational ocean reanalysis and forecasting *** contributions enhance the safety and stability of ocean subsurface activities and navigation.

关键词： HY-2 satellite observations subsurface structures reconstruction Maritime Silk Road operational thermohaline product

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