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Geochronological and geochemical constraints on the petrogenesis and geodynamic process of Hemler,Vlinder,and Il'ichev seamount lavas in NW Pacific

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Science China Earth Sciences 2024年第6期67卷 1856-1871页

作者： Xun WEI yan zhang Xuefa SHI Hui zhang Key Laboratory of Marine Geology and Metallogeny First Institute of OceanographyMinistry of Natural ResourcesQingdao 266061China Laboratory for Marine Geology Qingdao Marine Science and Technology CenterQingdao 266237China Shandong Key Laboratory of Deep Sea Mineral Resources Development(Preparatory) Qingdao 266061China

Oceanic intraplate volcanoes with linear age progressions are usually accepted to be derived from melting of an upwelling mantle *** seamount groups in NW Pacific,however,show complex age-distance relationships that are difficult to explain using the classic“mantle plume hypothesis”,and thus their origins are *** this study,we present ^(40)Ar-^(39)Ar age,geochemical,and Sr-Nd-Pb-Hf isotopic data of lavas from Hemler,Vlinder,and Il’ichev seamounts in NW Pacific,to elucidate their petrogenesis and geodynamic *** lavas from Hemler,Vlinder,and Il’ichev seamounts are classified as alkali basalt,basanite/nephelinite,and *** with Mg O>8 wt.%exhibit high contents of CaO,FeO^(T),and TiO_(2),similar to the composition of melts formed from reaction between carbonated eclogite-derived melts and fertile *** lavas have elevated Zr/Hf ratios(40.6-45.2)and negative Zr and Hf anomalies,indicating the presence of a carbonate component in the mantle *** are enriched in incompatible trace elements and have enriched mantle 1(EM1)-like SrNd-Pb-Hf isotopic *** isotopic compositions of Vlinder,Il’ichev basanite,and Hemler lavas in this study are similar to the Rarotonga *** occurring at the same seamount,the Il’ichev alkali basalts display more depleted SrNd-Hf isotopic compositions compared to Il’ichev *** to plate tectonic reconstruction results,the ages of Hemler(100.1 Ma),Vlinder pre-(100.2 Ma)and post-shield(87.5 Ma),and Il’ichev(56.4 Ma)lavas clearly deviate from the Macdonald,Arago,Rarotonga,and Samoa hotspot tracks,indicating that they cannot directly originate from mantle *** propose that in the mid-Cretaceous,when the Pacific plate passed over Rarotonga hotspot,melting of Rarotonga plume formed the Vlinder(main-shield stage),Pako,and Ioah *** Rarotonga(and possibly Samoa)plume materials would have been dispersed into the surrounding asthenosphere by mantle conve

关键词： Mantle plume Magellan seamount trail Carbonated mantle component Hotspot Lithosphere extension

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Precise Asymptotics in Limit Theorems for a Supercritical Branching Process with Immigration in a Random Environment

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Acta Mathematica Sinica,English Series 2024年第8期40卷 1850-1874页

作者： Chun Mao HUANG rui zhang Zhi Qiang GAO Department of Mathematics Harbin Institute of Technology(Weihai)Weihai 264209P.R.China School of Mathematical Sciences Beijing Normal UniversityBeijing 100875P.R.China

Let(Zn)be a supercritical branching process with immigration in an independent and identically distributed random *** necessary moment conditions,we show the exact convergence rate in the central limit theorem on log Zn and establish the corresponding local limit theorem by using the moments of the natural submartingale and the convergence rates of its *** similar approach and with the help of a change of measure,we also present the so-called integrolocal theorem and integral large deviation theorem to characterize the precise asymptotics of the upper large deviations.

关键词： Branching process with immigration random environment central limit theorem large deviation

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The Sasa-Satsuma equation with high-order discrete spectra in space-time solitonic regions:soliton resolution via the mixed■-Riemann-Hilbert problem

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Communications in Theoretical Physics 2024年第6期76卷 13-25页

作者： Minghe zhang Zhenya yan KLMM Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China

In this paper,we investigate the Cauchy problem of the Sasa-Satsuma(SS)equation with initial data belonging to the Schwartz *** SS equation is one of the integrable higher-order extensions of the nonlinear Schrödinger equation and admits a 3×3 Lax *** the aid of the■nonlinear steepest descent method of the mixed■-Riemann-Hilbert problem,we give the soliton resolution and long-time asymptotics for the Cauchy problem of the SS equation with the existence of second-order discrete spectra in the space-time solitonic regions.

关键词： Sasa-Satsuma equation inverse scattering ■-Riemann-Hilbert problem ■steepest descent method soliton resolution

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Early-diverging Titanosauriform(Dinosauria,Sauropoda)Teeth from the Lower Cretaceous Yixian Formation of Southeastern Inner Mongolia,Northeast China

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Acta Geologica Sinica(English Edition) 2024年第2期98卷 303-310页

作者： zhang Honggang YIN Yalei PEI rui ZHOU Changfu College of Earth Science and Engineering Shandong University of Science and TechnologyQingdaoShandong 266570China College of Paleontology Shenyang Normal UniversityShenyang 110034China Key Laboratory of Evolution of Past Life in NE Asia Ministry of Natural ResourcesShenyang 110034China Key Laboratory of Evolutionary Systematics of Vertebrates Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of SciencesBeijing 100044China CAS Center for Excellence in Life and Paleoenvironment Beijing 100044China

Three eusauropod teeth(SDUST-V1064,PMOL-AD00176,PMOL-ADt0005)are reported from the Lower Cretaceous Yixian Formation of Ningcheng,southeastern Inner Mongolia,*** of them(SDUST-V1064,PMOL-AD00176)are assigned to early-diverging titanosauriforms in having slightly mesiodistal expansion at the base of the tooth crown,a slenderness index value>2.0 and<4.0,and D-shaped cross ***,SDUST-V1064 and PMOL-AD00176 are referred as an Euhelopus-like titanosauriform on the basis of having a sub-circular boss on the lingual surface and an asymmetrical crown-root margin which slants apically,*** scan data of SDUST-V1064 reveals new dental information of early-diverging titanosauriforms,for example,the enamel on the labial side thicker than that on the lingual side,an enamel/dentine ratio of 0.26 and a boss present on the lingual side of the dentine of the crown.

关键词： teeth Titanosauriformes Lower Cretaceous Yixian Formation Ningcheng

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Facile synthesis of high-brightness green-emitting carbon dots with narrow bandwidth towards backlight display

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Chinese Chemical Letters 2024年第5期35卷 277-282页

作者： rui Cheng Tingting zhang Xin Huang Jian Yu State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringNanjing Tech UniversityNanjing 210009China

High-performance carbon dots(CDs)allowing the application in high-end display devices are highly desirable and usually limited by the absence of simple and easy synthesis *** this work,we exploited an easy-to-implement strategy for the one-step synthesis of green-emitting CDs(G-CDs)with superb optical *** G-CDs were synthesized using m-phenylenediamine(m-PD)as a single precursor,and the reaction reacted at 180℃for 12 h The resultant G-CDs exhibit high-purity and excitationindependent green fluorescence with the photoluminescence(PL)peak located at 516 nm,full width at half maximum(FWHM)of 46 nm,and PL quantum yield(QY)of∼80%under the 470nm excitation *** G-CDs and corresponding composite film prepared with polyvinyl butyral(G-CDs@PVB)exhibit good PL stability after undergoing long-time storage for one year and 360 h exposure under 460nm blue *** G-CDs@PVB film was used as color-conversion materials in green-emitting light-emitting diode(LED)application,exhibiting a Commission internationale de l’Eclairage(CIE)chromaticity coordinate of(0.21,0.44).The film was also used in CD-based liquid crystal display(CD-LCD)application,achieving a color gamut value of 85%.This work will offer a working basis for the synthesis of high-performance CDs as well as their application in displays.

关键词： Carbon dots One-step synthesis Narrow bandwidth High quantum yield Display

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Numerical Analysis of Perforation during Hydraulic Fracture Initiation Based on Continuous-Discontinuous Element Method

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Computer Modeling in Engineering & Sciences 2024年第8期140卷 2103-2129页

作者： rui zhang Lixiang Wang Jing Li Chun Feng Yiming zhang School of Civil and Transportation Engineering Hebei University of TechnologyTianjin300401China Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of MechanicsChinese Academy of SciencesBeijing100190China School of Civil Engineering and Architecture Zhejiang Sci-Tech UniversityHangzhou310018China Jinyun Institute Zhejiang Sci-Tech UniversityLishui321400China

Perforation is a pivotal technique employed to establish main flow channels within the reservoir formation at the outset of hydraulic fracturing *** perforation designs is critical for augmenting the efficacy of hydraulic fracturing and boosting oil or gas *** this study,we employ a hybrid finite-discrete element method,known as the continuous–discontinuous element method(CDEM),to simulate the initiation of post-perforation hydraulic fractures and to derive enhanced design *** model incorporates the four most prevalent perforation geometries,as delineated in an engineering technical ***-world perforations deviate from the ideal cylindrical shape,exhibiting variable cross-sectional profiles that typically manifest as an initial constriction followed by an expansion,a feature consistent across all four perforation *** simulations take into account variations in perforation hole geometries,cross-sectional diameters,and perforation *** findings show that perforations generated by the 39g DP3 HMX perforating bullet yield the lowest breakdown pressure,which inversely correlates with increases in sectional diameter and perforation ***,this study reveals the relationship between breakdown pressure and fracture degree,providing valuable insights for engineers and designers to refine perforation strategies.

关键词： Hydraulic fracturing real perforation shape breakdown pressure perforation layout design CDEM

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Automatic detection of small bowel lesions with different bleeding risks based on deep learning models

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World Journal of Gastroenterology 2024年第2期30卷 170-183页

作者： rui-Ya zhang Peng-Peng Qiang Ling-Jun Cai Tao Li yan Qin Yu zhang Yi-Qing Zhao Jun-Ping Wang Department of Gastroenterology The Fifth Clinical Medical College of Shanxi Medical UniversityTaiyuan 030012Shanxi ProvinceChina School of Computer and Information Technology Shanxi UniversityTaiyuan 030006Shanxi ProvinceChina School of Life Sciences and Technology Mudanjiang Normal UniversityMudanjiang 157011Heilongjiang ProvinceChina

BACKGROUND Deep learning provides an efficient automatic image recognition method for small bowel(SB)capsule endoscopy(CE)that can assist physicians in ***,the existing deep learning models present some unresolved *** To propose a novel and effective classification and detection model to automatically identify various SB lesions and their bleeding risks,and label the lesions accurately so as to enhance the diagnostic efficiency of physicians and the ability to identify high-risk bleeding *** The proposed model represents a two-stage method that combined image classification with object ***,we utilized the improved ResNet-50 classification model to classify endoscopic images into SB lesion images,normal SB mucosa images,and invalid ***,the improved YOLO-V5 detection model was utilized to detect the type of lesion and its risk of bleeding,and the location of the lesion was *** constructed training and testing sets and compared model-assisted reading with physician *** The accuracy of the model constructed in this study reached 98.96%,which was higher than the accuracy of other systems using only a single *** sensitivity,specificity,and accuracy of the model-assisted reading detection of all images were 99.17%,99.92%,and 99.86%,which were significantly higher than those of the endoscopists’*** image processing time of the model was 48 ms/image,and the image processing time of the physicians was 0.40±0.24 s/image(P<0.001).CONCLUSION The deep learning model of image classification combined with object detection exhibits a satisfactory diagnostic effect on a variety of SB lesions and their bleeding risks in CE images,which enhances the diagnostic efficiency of physicians and improves the ability of physicians to identify high-risk bleeding groups.

关键词： Artificial intelligence Deep learning Capsule endoscopy Image classification Object detection Bleeding risk

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Indexing dynamic encrypted database in cloud for efficient secure k-nearest neighbor query

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Frontiers of Computer Science 2024年第1期18卷 187-198页

作者： Xingxin LI Youwen ZHU rui XU Jian WANG Yushu zhang College of Computer Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016China Department of Mathematical Informatics University of TokyoTokyo 113-8654Japan Guangxi Key Laboratory of Trusted Software Guilin University of Electronic TechnologyGuilin 541004China School of Computer Science China University of GeosciencesWuhan 430074China

Secure k-Nearest Neighbor(k-NN)query aims to find k nearest data of a given query from an encrypted database in a cloud server without revealing privacy to the untrusted cloud and has wide applications in many areas,such as privacy-preservingmachine elearning gand secure biometric *** solutions have been put forward to solve this challenging ***,the existing schemes still suffer from various limitations in terms of efficiency and *** this paper,we propose a new encrypt-then-index strategy for the secure k-NN query,which can simultaneously achieve sub-linear search complexity(efficiency)and support dynamical update over the encrypted database(flexibility).Specifically,we propose a novel algorithm to transform the encrypted database and encrypted query points in the *** indexing the transformed database using spatial data structures such as the R-tree index,our strategy enables sub-linear complexity for secure k-NN queries and allows users to dynamically update the encrypted *** the best of our knowledge,the proposed strategy is the first to simultaneously provide these two *** theoretical analysis and extensive experiments,we formally prove the security and demonstrate the efficiency of our scheme.

关键词： cloud computing secure k-NN query sub-linear complexity dynamicupdate

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Optimizing extractants selection for efficient separation of phenols and nitrogen-containing heteroaromatics using hydrogen bond interaction strategies

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Chinese Journal of Chemical Engineering 2024年第4期68卷 43-52页

作者： Pengzhi Bei rui zhang Jie Feng Antony Rajendran Wenying Li State Key Laboratory of Clean and Efficient Coal Utilization Taiyuan University of TechnologyTaiyuan 030024China Department of Chemistry Mepco Schlenk Engineering College(Autonomous)Sivakasi 626005India

Focusing on the use of imidazolium ionic liquids and quaternary ammonium salts-based deep eutectic solvents for the separation of phenols and nitrogen-containing heteroaromatics,the role of heteroaromatics as specific sites for hydrogen bond-based separation has been *** environmentally friendly solvents are known for their ability to form hydrogen bonds with heteroatoms,a key aspect in separation *** quantified the hydrogen bond interaction energy to reach the threshold energy for efficient O-and N-heteroaromatics *** article provides an in-depth study of the structural nuances of different hydrogen bonding sites and their affinity properties while conducting a comparative evaluation of the separation efficiency of ionic liquids and deep eutectic solvents from a thermodynamic *** showed that phenols with dual hydrogen bonding recognition sites were easier to separate than nitrogen-containing *** ionic liquids were more suitable for the extraction of nonbasic nitrogen-containing heteroaromatics,and quaternary ammonium salts-based deep eutectic solvents are more effective for phenols and basic nitrogen-containing heteroaromatics,which was confirmed by Fourier transform infrared spectroscopy and empirical ***,this study provides a theoretical basis for the strategy design and selection of extractants for the efficient separation of O-and N-containing aromatic compounds.

关键词： Deep eutectic solvents Hydrogen bond Ionic liquids Separation Solvents Structural characteristics

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Deep neural network-enabled battery open-circuit voltage estimation based on partial charging data

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Journal of Energy Chemistry 2024年第3期90卷 120-132,I0005页

作者： Ziyou Zhou Yonggang Liu Chengming zhang Weixiang Shen rui Xiong State Key Laboratory of Mechanical Transmission for Advanced Equipment&College of Mechanical and Vehicle Engineering Chongqing UniversityChongqing 400000China Department of Vehicle Engineering School of Mechanical EngineeringBeijing Institute of TechnologyBeijing 100081China Department of Electrical Engineering Harbin Institute of TechnologyHarbin 150000HeilongjiangChina School of Science Computing and Engineering TechnologiesSwinburne University of TechnologyHawthornVictoria 3122Australia

Battery management systems(BMSs) play a vital role in ensuring efficient and reliable operations of lithium-ion *** main function of the BMSs is to estimate battery states and diagnose battery health using battery open-circuit voltage(OCV).However,acquiring the complete OCV data online can be a challenging endeavor due to the time-consuming measurement process or the need for specific operating conditions required by OCV estimation *** addressing these concerns,this study introduces a deep neural network-combined framework for accurate and robust OCV estimation,utilizing partial daily charging *** incorporate a generative deep learning model to extract aging-related features from data and generate high-fidelity OCV *** analysis is employed to identify the optimal partial charging data,optimizing the OCV estimation precision while preserving exceptional *** validation results,using data from nickel-cobalt-magnesium(NCM) batteries,illustrate the accurate estimation of the complete OCV-capacity curve,with an average root mean square errors(RMSE) of less than 3 *** this level of precision for OCV estimation requires only around 50 s collection of partial charging *** validations on diverse battery types operating under various conditions confirm the effectiveness of our proposed *** cases of precise health diagnosis based on OCV highlight the significance of conducting online OCV *** method provides a flexible approach to achieve complete OCV estimation and holds promise for generalization to other tasks in BMSs.

关键词： Lithium-ion battery Open-circuit voltage Health diagnosis Deep learning

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