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Early Cretaceous Metasomatized Lithospheric Mantle beneath the Central Jiangnan Orogen in South China:Geochemical and Sr-Nd Isotope Evidence from the Tuanshanbei Dolerite

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 602-616页

作者： WANG cheng WEI Hantao liu Qingquan YANG Zhao Guangdong Provincial Key Laboratory of Geodynamics and Geohazards School of Earth Sciences and EngineeringSun Yat-sen UniversityGuangzhou 510275China Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring Ministry of EducationSchool of Geosciences and Info-PhysicsCentral South UniversityChangsha 410083China Development and Research Centre China Geological SurveyBeijing 100037China School of Environmental Studies China University of GeosciencesWuhan 430074China

It is well established that Cretaceous magmatism in the South China Block(SCB)is related to the Paleo-Pacific ***,the starting time and the associated deep crust-mantle processes are still *** dike swarms carry important information on the deep earth(including mantle)geodynamics and geochemical *** the Jiangnan Orogen(South China).there is no information on whether the Mesozoic magmatic activities in this region are also directly related to the Pacific subduction or *** this study,we present detailed zircon U-Pb geochronological,wholerock element and Sr-Nd isotope data for Early Cretaceous Tuanshanbei dolerite dikes,and provide new constraints on the condition of the lithospheric mantle and mantle dynamics of the SCB during that ***-ICP-MS zircon U-Pb dating suggests that this dolerite erupted in the Early Cretaceous(~145 Ma).All samples have alkaline geochemical affinities with K_(2)O+Na_(2)O=3.11-4.04 wt%,K_(2)O/Na_(2)O=0.50-0.72,and Mg^(#)=*** are enriched in LILE but depleted in HFSE with higher initial^(87)Sr/^(86)Sr ratio(0.706896-0.714743)and lower ε_(Nd)(t)(-2.61 to-1.67).They have high Nb/U,Nb/La,La/Sm and Rb/Sr,and low La/Nb,La/Ta,Ce/Pb,Ba/Rb,Tb/Yb and Gd/Yb *** geochemical signatures suggest that the fractional crystallization is obvious but crustal contamination play a negligible role during magmatic *** dolerite were most likely derived from low-degree(2%-5%)partial melting of a phlogopite-bearing mantle material consisted of~85% spinel peridotite and~15% garnet peridotite previously metasomatized by asthenospherederived fluids/melts with minor subduction-derived fluids/***-rollback generally lead to the upwelling of the hot *** upwelling of asthenosphere consuming the lithospheric mantle by thermo-mechanical-chemical *** lithospheric mantle may have partially melted due to the heating by the upwelling asthenosphere and lithospheric extension.I

关键词： Early Cretaceous mafic dike metasomatized lithospheric mantle Tuanshanbei dolerite Jiangnan Orogen South China

Transformer-Based Cloud Detection Method for High-Resolution Remote Sensing Imagery

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Computers, Materials & Continua 2024年第7期80卷 661-678页

作者： Haotang Tan Song sun Tian cheng Xiyuan Shu Key Laboratory of GIS Application Research School of Geography and TourismChongqing Normal UniversityChongqing401331China College of Computer and Information Science Chongqing Normal UniversityChongqing401331China Department of Military Installations Army Logistics AcademyChongqing401331China

Cloud detection from satellite and drone imagery is crucial for applications such as weather forecasting and *** the limitations of conventional convolutional neural networks,we propose an innovative transformer-based *** method leverages transformers,which are adept at processing data sequences,to enhance cloud detection ***,we introduce a Cyclic Refinement Architecture that improves the resolution and quality of feature extraction,thereby aiding in the retention of critical details often lost during cloud *** extensive experimental validation shows that our approach significantly outperforms established models,excelling in high-resolution feature extraction and precise cloud *** integrating Positional Visual Transformers(PVT)with this architecture,our method advances high-resolution feature delineation and segmentation ***,our research offers a novel perspective for surmounting traditional challenges in cloud detection and contributes to the advancement of precise and dependable image analysis across various domains.

关键词： Cloud transformer image segmentation remotely sensed imagery pyramid vision transformer

circPVT1 promotes silica-induced epithelial-mesenchymal transition by modulating the miR-497-5p/TCF3 axis

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Journal of Biomedical Research 2024年第2期38卷 163-174,I0011-I0015页

作者： Siyun Zhou Yan Li Wenqing sun Dongyu Ma Yi liu Demin cheng Guanru Li Chunhui Ni Department of Occupational Medical and Environmental Health Key Laboratory of Modern Toxicology of Ministry of EducationCenter for Global HealthSchool of Public HealthNanjing Medical UniversityNanjingJiangsu 211166China Biomedical Publications Center Nanjing Medical UniversityNanjingJiangsu 211166China Gusu School Nanjing Medical UniversityNanjingJiangsu 211166China

Epithelial-mesenchymal transition(EMT)is a vital pathological feature of silica-induced pulmonary ***,whether circRNA is involved in the process remains *** present study aimed to investigate the role of circPVT1 in the silica-induced EMT and the underlying *** found that an elevated expression of circPVT1 promoted EMT and enhanced the migratory capacity of silica-treated epithelial *** isolation of cytoplasmic and nuclear separation assay showed that circPVT1 was predominantly expressed in the *** immunoprecipitation assay and RNA pull-down experiment indicated that cytoplasmic-localized circPVT1 was capable of binding to ***,we found that miR-497-5p attenuated the silica-induced EMT process by targeting transcription factor 3(TCF3),an E-cadherin transcriptional repressor,in the silica-treated epithelial ***,these results reveal a novel role of the circPVT1/miR-497-5p/TCF3 axis in the silica-induced EMT process in lung epithelial *** validated,this finding may provide a potential theoretical basis for the development of interventions and treatments for pulmonary fibrosis.

关键词： silicosis epithelial-mesenchymal transition circPVT1 miR-497-5p TCF3

Asymmetric Synthesis of Dihydrospirotryprostatin B via a Silica Gel-Mediated Cyclization of Tryptamine-Ynamide

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Chinese Journal of Chemistry 2024年第12期42卷 1355-1359页

作者： Changhong Han Lu Yang Kaizong Yao Sen Zhang Jiayue Fu Hanyang sun Hongsheng Xu Bin Lin Maosheng cheng Yongxiang liu Key Laboratory of Structure:Based Drug Design and Discovery of Ministry of Education Shenyang Pharmaceutical UniversityShenyangLiaoning 110016China Wuya College of Innovation Shenyang Pharmaceutical UniversityShenyangLiaoning 110016China Institute of Drug Research in Medicine Capital of China BenxiLiaoning 117000China Zhejiang Shapuaisi Pharmaceutical Co. LtdPinghuZhejiang 314299China

Comprehensive Summary An asymmetric synthesis of dihydrospirotryprostatin B was achieved in 15 steps(8 purifications)from *** main feature of our synthetic strategy is the efficient construction of spirocyclic oxindole intermediate containing a chiral quaternary carbon center,involving the silica gel-mediated cyclization of tryptamine-ynamide and oxidation under neat conditions.

关键词： Asymmetric synthesis Alkaloids Dihydrospirotryprostatin B Tryptamine-ynamide Cross-coupling Silica gel-mediated cyclization Oxidation

The Spatiotemporal Distribution Characteristics of Cloud Types and Phases in the Arctic Based on CloudSat and CALIPSO Cloud Classification Products

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Advances in Atmospheric Sciences 2024年第2期41卷 310-324页

作者： Yue sun Huiling YANG Hui XIAO Liang FENG Wei cheng Libo ZHOU Weixi SHU Jingzhe sun Key Laboratory of Cloud-Precipitation Physics and Severe Storms(LACS) and Department of Lower Atmospheric Observation Research(LAOR)Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China College of Earth Sciences University of Chinese Academy of Sciences(UCAS)Beijing 100049China Beijing Institute of Applied Meteorology Beijing 100029China

The cloud type product 2B-CLDCLASS-LIDAR based on CloudSat and CALIPSO from June 2006 to May 2017 is used to examine the temporal and spatial distribution characteristics and interannual variability of eight cloud types(high cloud, altostratus, altocumulus, stratus, stratocumulus, cumulus, nimbostratus, and deep convection) and three phases(ice,mixed, and water) in the Arctic. Possible reasons for the observed interannual variability are also discussed. The main conclusions are as follows:(1) More water clouds occur on the Atlantic side, and more ice clouds occur over continents.(2)The average spatial and seasonal distributions of cloud types show three patterns: high clouds and most cumuliform clouds are concentrated in low-latitude locations and peak in summer;altostratus and nimbostratus are concentrated over and around continents and are less abundant in summer;stratocumulus and stratus are concentrated near the inner Arctic and peak during spring and autumn.(3) Regional averaged interannual frequencies of ice clouds and altostratus clouds significantly decrease, while those of water clouds, altocumulus, and cumulus clouds increase significantly.(4) Significant features of the linear trends of cloud frequencies are mainly located over ocean areas.(5) The monthly water cloud frequency anomalies are positively correlated with air temperature in most of the troposphere, while those for ice clouds are negatively correlated.(6) The decrease in altostratus clouds is associated with the weakening of the Arctic front due to Arctic warming, while increased water vapor transport into the Arctic and higher atmospheric instability lead to more cumulus and altocumulus clouds.

关键词： CloudSat and CALIPSO cloud type cloud phase temporal and spatial distribution interannual variation

Interfacial friction effects on sealing performances of elastomer packer

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Petroleum Science 2024年第3期21卷 2037-2047页

作者： Peng-cheng Wang Ming-Hui Chen Jim Jenkinson Yong-Xin Song Li sun Department of Mechanical Engineering University of HoustonHoustonTX77024USA Guren Nanomaterials Suzhou215127JiangsuChina Department of Marine Engineering Dalian Maritime UniversityDalian116026LiaoningChina

Elastomer sealing performance is of critical importance for downhole tools application including the use of fracturing(Frac)plugs during multi-stage hydraulic *** practice sealing performances of such plugs are normally evaluated through pressure tests,and in numerical simulation studies,maximum contact stress,average contact stress and contact length data are used to determine sealing quality between a packer and *** previous studies,the impact of friction forces on sealing performance is often *** work aims to fill this knowledge gap in determining the influence of friction forces on elastomer packer sealing *** first determined the most appropriate constitutive hyperelastic model for the elastomers used in frac *** we compared analytical calculation results with Finite Element Analysis simulation using a simplified tubular geometry and showed the significant influences on interfacial friction on elastomer packer stress distribution,deformation,and contact stress after *** the demonstration of validity of FEA method,we conducted systematic numerical simulation studies to show how the interfacial friction coefficients can affect the maximum contact stress,average contact stress,contact stress distribution,and maximum mises stress for an actual packer used in plug *** addition,we also demonstrated how the groove in a packer can affect packer deformation and evolvement during setting with the consideration of interfacial *** study underscores the critical role that friction forces play in Frac plug performance and provides a new dimension for optimizing packer design by controlling interfacial interactions at the packer contact surfaces.

关键词： Elastomer seal Friction Sealing performance Contact stress

Research on a TOPSIS energy efficiency evaluation system for crude oil gathering and transportation systems based on a GA-BP neural network

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Petroleum Science 2024年第1期21卷 621-640页

作者： Xue-Qiang Zhang Qing-Lin cheng Wei sun Yi Zhao Zhi-Min Li Key Lab of Ministry of Education for Enhancing the Oil and Gas Recovery Ratio Northeast Petroleum UniversityDaqing163318HeilongjiangChina China Petroleum Pipeline Material and Equipment Co. LtdLangfang065000HebeiChina Research Institute of Petroleum Engineering and Technology Sinopec Northwest Oilfield CompanyUrumqi830011XinjiangChina

As the main link of ground engineering,crude oil gathering and transportation systems require huge energy consumption and complex *** is necessary to establish an energy efficiency evaluation system for crude oil gathering and transportation systems and identify the energy efficiency *** this paper,the energy efficiency evaluation system of the crude oil gathering and transportation system in an oilfield in western China is *** with the big data analysis method,the GA-BP neural network is used to establish the energy efficiency index prediction model for crude oil gathering and transportation *** comprehensive energy consumption,gas consumption,power consumption,energy utilization rate,heat utilization rate,and power utilization rate of crude oil gathering and transportation systems are *** the efficiency and unit consumption index of the crude oil gathering and transportation system,the energy efficiency evaluation system of the crude oil gathering and transportation system is established based on a game theory combined weighting method and TOPSIS evaluation method,and the subjective weight is determined by the triangular fuzzy analytic hierarchy *** entropy weight method determines the objective weight,and the combined weight of game theory combines subjectivity with objectivity to comprehensively evaluate the comprehensive energy efficiency of crude oil gathering and transportation systems and their ***,the weak links in energy utilization are identified,and energy conservation and consumption reduction are *** above research provides technical support for the green,efficient and intelligent development of crude oil gathering and transportation systems.

关键词： Crude oil gathering and transportation system GA-BP neural network Energy efficiency evaluation TOPSIS evaluation method Energy saving and consumption reduction

Microstructures and mechanical properties of laser-directed energy deposited CrCoNi medium-entropy alloy

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Rare Metals 2024年第7期43卷 3286-3300页

作者： Wen-Jie Zhao Chang-Yu liu Peng-cheng Che Zhi-Liang Ning Hong-Bo Fan Jian-Fei sun Yong-Jiang Huang Alfonso H.W.Ngan National Key Laboratory for Precision Hot Processing of Metals Harbin Institute of TechnologyHarbin 150001China Space Environment Simulation Research Infrastructure Harbin Institute of TechnologyHarbin 150001China Department of Mechanical Engineering The University of Hong KongHong Kong 999077China

The distinctive intrinsic heat treatment(IHT)originating from cyclic reheating in the laser-directed energy deposition(LDED) has attracted growing attention in recent *** this investigation,simulations and experimental characterizations were performed to examine the impact of IHT on the micros true ture and mechanical properties of LDED-fabricated CrCoNi medium-entropy alloy(MEA).The results show that the intensity of the IHT is proportional to the utilized laser energy density(LED).As the LED increased,significant dynamic recrystallization and grain refinement occurred within the alloy due to the enhanced intensity of ***,the high LED leads to severe hot cracking within the as-built MEA,resulting in inferior *** decreasing LED,the hot cracking was effectively ***,low LED weakened the intensity of IHT and consequently inhibited kinetic conditions of dynamic recrystallization,resulting in a heterogeneous grain structure characterized by multi-scale-sized *** structure provides significant hetero-deformation-induced hardening during plastic deformation,enabling the alloy to have a sustainable work-hardening *** expect that this work will have implications in taking full advantage of the unique IHT of the LDED process to fabricate ME As with excellent metallurgical quality and mechanical performance.

关键词： Intrinsic heat treatment Laser-directed energy deposition CrCoNi MEA Dynamic recrystallization Heterogeneous grain structure

A Fluorine-Functionalized 3D Covalent Organic Framework with Entangled 2D Layers

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Chinese Journal of Polymer Science 2024年第8期42卷 1210-1216页

作者： Li-Bang Xiao Zi-Han Wu Jun-Jie Xin Yuan-Peng cheng Bo Gui Jun-Liang sun cheng Wang College of Chemistry and Molecular Sciences Wuhan UniversityWuhan 430072China College of Chemistry and Molecular Engineering Beijing National Laboratory for Molecular SciencesPeking UniversityBeijing 100871China

Constructing three dimensional(3D)covalent organic frameworks(COFs)through the entanglement of two dimensional(2D)nets is a promising but underdeveloped ***,we report the design and synthesis of a fluorine functionalized 3DCOF(3D-An-COF-F)formed by entangled 2D sql *** structure of 3D-An-COF-F was determined by the combination of continuous rotation electron diffraction technique and modelling based on the chemical information from real ***,compared to the isostructural 3D-An-COF without F atom s,3DAn-COF-F showed an improved CO_(2)sorption ability and higher CO_(2)/N_(2)*** study not only demonstrated the generality of constructing 3D COFs with entangled 2D nets by introducing bulky groups vertically in planar building blocks,but also will expand the diversity of 3D COFs for various applications.

关键词： 3D covalent organic frameworks Fluorine Entangled 2D layers Electron diffraction CO_(2)adsorption