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Biological sources, paleoenvironment, and organic matter enrichment in source rocks of the Ordovician Majiagou Formation, Ordos Basin, China:Evidence from biomarkers,microfossils, and inorganic geochemical analyses

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Journal of Palaeogeography 2024年第1期13卷 92-115页

作者： Jing-Jing Cao wen-zhe gang Shang-Ru Yang State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Bejing)Beijing 102249China College of Geosciences China University of Petroleum(Bejing)Beijing 102249China Oil and Gas Technology Research Institute PetroChina Changqing Oifield CompanyXi'an 710018Shaanxi ProvinceChina

Carbonate deposits in the Ordovivian Majiagou Formation are significant source rocks for natural gas generation in the Ordos Basin, northwestern China. Previous studies mainly focused on the organic matter enrichment mechanism of shales rather than carbonate rocks. The biological sources and paleoenvironment of carbonate source rocks, and the main controlling factors of organic matter enrichment in the carbonate source rocks were studied in this paper in combination with evidence from biomarkers, microfossils and inorganic geochemistry analysis. The results show that four types of microfacies were identified in the Majiagou Formation, respectively as: mud flat microfacies, mud-dolomite flat microfacies, dolomite flat microfacies, and open marine microfacies. The biological sources of organic matter are chiefly planktonic algae, followed by bacteria. The mud flat and mud-dolomite flat contain a high abundance of terrigenous detrital inputs, as indicated by the high content of Al_(2)O_(3), TiO_(2), Th, and Zr. The low Sr/Cu and high Rb/Sr values reveal warm and humid paleoclimate conditions in the mud flat and mud-dolomite flat, whereas the dolomite flat and open marine were likely formed in hot and arid paleoclimate conditions. The mud flat and mud-dolomite flat deposits were characterized by high paleoproductivity of the Majiagou Formation. Low Sr/Ba values were found in the mud flat samples, indicating fresh to brackish water condition, whereas samples of other facies have a relatively high degree of salinity. Based on U_(auth), Mo_(auth), Cr_(auth), Co_(auth), δCe, and δEu values, the mud flat microfacies was formed in a suboxic and anoxic environment, whereas the mud-dolomite flat, dolomite flat and open marine microfacies were within dysoxic to oxic conditions. A model of organic matter enrichment in the Majiagou Formation is thus established. The level of terrigenous detrital inputs is the principal factor of organic matter enrichment in the Majiagou Formation,

关键词： Biological source Microfacies Trace elements Organic matter Majiagou Formation Ordos Basin

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Differences in geochemistry and hydrocarbon generation of sourcerock samples dominated by telalginite and lamalginite: A case study on the Permian saline lacustrine source rocks in the Jimusaer Sag, NW China

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Petroleum Science 2023年第1期20卷 141-160页

作者： Shi-Ju Liu gang Gao wen-zhe gang Bao-Li Xiang Ming Wang College of Geosciences China University of PetroleumNo.18 Fuxue RoadBeijing102249China State Key Laboratory of Petroleum Resource and Prospecting China University of PetroleumNo.18 Fuxue RoadBeijing102249China Experimental Testing Institute PetroChina Xinjiang Oilfield CompanyKaramayXinjiang834000China

The Middle Permian Lucaogou Formation in Northwestern China mainly contains typical saline lacustrine oil *** study the differences in geochemistry and hydrocarbon generation of source-rock samples in Lucaogou Formation in Jimusaer Sag,57 core samples from two boreholes were analyzed herein by performing total organic carbon(TOC)analysis,RockeEval pyrolysis,and gas chromatographicemass spectrometry experiments on saturated *** kinetics of oil generation were studied using two samples comprising typical maceral *** results showed that the hydrocarbons produced by telalginite are relatively rich in pristane(Pr),phytane(Ph),b-carotane,high-carbon normal alkanes,and C29 regular *** produced by lamalginite contain a significantly higher content of C20 tricyclic terpanes(TT),C21TT,C24 tetracyclic terpanes(TeT),C29 norhopane,and C28 regular *** on the pyrolysis and biomarker compound parameters,telalginite has a higher conversion rate for hydrocarbons than lamalginite in the low-mature to mature stage,which is consistent with their kinetic *** source rock displays a much narrower distribution of activation energies than telalginite source *** narrower activation energy distribution effectively narrows the main stage of hydrocarbon *** addition,the activation energy distribution of lamalginite concentrated in the high-value interval,indicating the characteristics of the relatively lagging hydrocarbon generation of lamalginite.

关键词： Maceral component Biomarker compounds Oil generation kinetics Activation energy Lucaogou formation

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Aircraft parameter estimation using a stacked long short-term memory network and Levenberg-Marquardt method

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Chinese Journal of Aeronautics 2024年第2期37卷 123-136页

作者： zhe HUI Yinan KONG Weigang YAO gang CHEN School of Aerospace Science and Technology Xidian UniversityXi’an 710071China Computation Aerodynamics Institution China Aerodynamics Research and Development CenterMianyang 621000China Faculty of Computing Engineering and MediaDe Montfort UniversityLeicester LE19BHUnited Kingdom School of Aerospace Engineering Xi’an Jiaotong UniversityXi’an 710049China

To effectively estimate the unknown aerodynamic parameters from the aircraft’s flight data,this paper proposes a novel aerodynamic parameter estimation method incorporating a stacked Long Short-Term Memory(LSTM)network model and the Levenberg-Marquardt(LM)*** stacked LSTM network model was designed to realize the aircraft dynamics modeling by utilizing a frame of nonlinear functional mapping based entirely on the measured input-output data of the aircraft system without requiring explicit postulation of the *** LM method combines the already-trained LSTM network model to optimize the unknown aerodynamic *** proposed method is applied by using the real flight data,generated by ATTAS aircraft and a bio-inspired morphing Unmanned Aerial Vehicle(UAV).The investigation reveals that for the two different flight data,the designed stacked LSTM network structure can maintain the efficacy of the network prediction capability only by appropriately adjusting the dropout rates of its hidden layers without changing other network parameters(i.e.,the initial weights,initial biases,number of hidden cells,time-steps,learning rate,and number of training iterations).Besides,the proposed method’s effectiveness and potential are demonstrated by comparing the estimated results of the ATTAS aircraft or the bio-inspired morphing UAV with the corresponding reference values or wind-tunnel results.

关键词： Parameter estimation LSTM network model LM method Aerodynamic parameters Flight data Aircraft dynamics modeling Network prediction capability Network parameters

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Distributed dynamic task allocation for unmanned aerial vehicle swarm systems:A networked evolutionary game-theoretic approach

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Chinese Journal of Aeronautics 2024年第6期37卷 182-204页

作者： zhe ZHANG Ju JIANG Haiyan XU wen-An ZHANG College of Automation Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China College of Economics and Management Nanjing University of Aeronautics and AstronauticsNanjing 211106China College of Information Engineering Zhejiang University of TechnologyHangzhou 310023China

Task allocation is a key aspect of Unmanned Aerial Vehicle(UAV)swarm collaborative *** an continuous increase of UAVs’scale and the complexity and uncertainty of tasks,existing methods have poor performance in computing efficiency,robustness,and realtime allocation,and there is a lack of theoretical analysis on the convergence and optimality of the *** paper presents a novel intelligent framework for distributed decision-making based on the evolutionary game theory to address task allocation for a UAV swarm system in uncertain scenarios.A task allocation model is designed with the local utility of an individual and the global utility of the ***,the paper analytically derives a potential function in the networked evolutionary potential game and proves that the optimal solution of the task allocation problem is a pure strategy Nash equilibrium of a finite strategy ***,a PayOff-based Time-Variant Log-linear Learning Algorithm(POTVLLA)is proposed,which includes a novel learning strategy based on payoffs for an individual and a time-dependent Boltzmann *** former aims to reduce the system’s computational burden and enhance the individual’s effectiveness,while the latter can ensure that the POTVLLA converges to the optimal Nash equilibrium with a probability of *** simulation results show that the approach is optimal,robust,scalable,and fast adaptable to environmental changes,even in some realistic situations where some UAVs or tasks are likely to be lost and increased,further validating the effectiveness and superiority of the proposed framework and algorithm.

关键词： Task allocation Unmanned Aerial Vehicles(UAV) Game theory Log-linear learning Distributed optimization algorithm

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Porous nanofibrous dressing enables mesenchymal stem cell spheroid formation and delivery to promote diabetic wound healing

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Chinese Journal of Chemical Engineering 2024年第4期68卷 156-164页

作者： Kexin Zhang wenmin Zhang Heng An zhe Huang Yanzhen wen Xiangyu Jiao Yongqiang wen College of Chemical Engineering and Technology Taiyuan University of Science and TechnologyTaiyuan 030024China Beijing Key Laboratory for Bioengineering and Sensing Technology Daxing Research InstituteSchool of Chemistry&Biological EngineeringUniversity of Science&Technology BeijingBeijing 100083China

Delayed and nonhealing of diabetic wounds imposes substantial economic burdens and physical pain on *** stem cells(MSCs)promote diabetic wound *** when MSCs aggregate into multicellular spheroids,their therapeutic effect is ***,traditional culture platforms are inadequate for the efficient preparation and delivery of MSC spheroids,resulting in inefficiencies and inconveniences in MSC spheroid *** this study,a three-dimensional porous nanofibrous dressing(NFD)is prepared using a combination of electrospinning and homogeneous *** thermal crosslinking,the NFD not only achieves satisfactory elasticity but also maintains notable *** the design of its structure and chemical composition,the NFD allows MSCs to spontaneously form MSC spheroids with controllable sizes,serving as MSC spheroid delivery systems for diabetic wound *** importantly,MSC spheroids cultured on the NFD exhibit improved secretion of vascular endothelial growth factor,basic fibroblast growth factor,and hepatocyte growth factor,thereby accelerating diabetic wound *** NFD provides a competitive strategy for MSC spheroid formation and delivery to promote diabetic wound healing.

关键词： Electrospinning Homogenization Biomedical engineering Nanomaterials Stem cell spheroids Diabetic wound healing

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Index-free triangle-based graph local clustering

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Frontiers of Computer Science 2024年第3期18卷 143-153页

作者： zhe YUAN zhewei WEI Fangrui LV Ji-Rong wen The Country and Area Studies Academy Beijing Foreign Studies UniversityBeijing 100089China Gaoling School of Artificial Intelligence Renmin University of ChinaBeijing 100872China

Motif-based graph local clustering(MGLC)is a popular method for graph mining tasks due to its various ***,the traditional two-phase approach of precomputing motif weights before performing local clustering loses locality and is impractical for large *** some attempts have been made to address the efficiency bottleneck,there is still no applicable algorithm for large scale graphs with billions of *** this paper,we propose a purely local and index-free method called Index-free Triangle-based Graph Local Clustering(TGLC^(*))to solve the MGLC problem w.r.t.a ***^(*)directly estimates the Personalized PageRank(PPR)vector using random walks with the desired triangleweighted distribution and proposes the clustering result using a standard sweep *** demonstrate TGLC^(*)’s scalability through theoretical analysis and its practical benefits through a novel visualization ***^(*)is the first algorithm to solve the MGLC problem without precomputing the motif *** experiments on seven real-world large-scale datasets show that TGLC^(*)is applicable and scalable for large graphs.

关键词： graph local clustering triangle motif index-free sampling method visualization

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Tool for Determinization of Büchi Automata

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Ruan Jian Xue Bao/Journal of Software 2024年第9期35卷

作者： Ma, Run-zhe Tian, Cong Wang, wen-Sheng Duan, zhen-Hua School of Computer Science and Technology Xidian University Xi’an 710071 China

The ω automata determinization is an important part of theoretical computer research and has important applications in formal verification, sequential logic, and model checking. Since the Büchi automata was proposed for half a century, its deterministic algorithm has always been the basis. Different from the exploration of the upper and lower bounds of its size in theory at the beginning, the use of ever-changing high-performance computer technology is an effective auxiliary means. To deeply study the implementation process of the deterministic algorithm of non-deterministic Büchi automata, this study focuses on the question of whether the index can continue to be optimized and realizes the deterministic research tool NB2DR. The non-deterministic Büchi automata can be determined efficiently, and the determinization algorithm can be improved by analyzing the determinization process provided by the tool. A theoretical upper bound on correlation indexing is explored through an in-depth analysis of the indexing of generated deterministic ω automata. The tool also realizes that the deterministic Rabin automaton family can be generated according to the size of the required Büchi automaton and the alphabet parameters. It can also be reversed to generate all the Büchi automata families according to the size of the specified index required and test the equivalence of ω functions. © 2024 Chinese Academy of Sciences. All rights reserved.

关键词： Model checking

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Photocatalytic dicarboxylation of strained C-C bonds with CO_(2) via consecutive visible-light-induced electron transfer

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Chinese Chemical Letters 2024年第6期35卷 268-273页

作者： Yi Liu zhe-Hao Wang Guan-Hua Xue Lin Chen Li-Hua Yuan Yi-wen Li Da-gang Yu Jian-Heng Ye Key Laboratory of Green Chemistry&Technology of Ministry of Education College of ChemistrySichuan UniversityChengdu 610064China College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065China State Key Laboratory of Elemento-Organic Chemistry Nankai UniversityTianjin 300071China

Dicarboxylic acids have a wide range of applications in the polymer industry to construct valuable *** has recently emerged as an efficient and sustainable strategy to generate dicarboxylic ***,photocatalytic dicarboxylation with CO_(2) is mainly limited to unsaturated bonds,and the dicarboxylation of C-C single bonds still remains a ***,we report a photocatalytic dicarboxylation of C-C single bonds in strained rings with CO_(2) units via consecutive photo-induced electron transfer(ConPET).It is also the first photocatalytic reductive ring-opening reaction of ***,this transition-metal-free protocol exhibits good functional group tolerance,broad substrate scope,facile scalability,and easy product ***,diacids can easily be derivatized to mainchain liquid crystalline polyesters.

关键词： Consecutive photo-induced electron transfer Visible-light catalysis Dicarboxylation Carbon dioxide Cyclopropanes

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Visualization analysis of research hotspots and trends on gastrointestinal tumor organoids

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World Journal of Gastrointestinal Oncology 2024年第6期16卷 2826-2841页

作者： gang Wang Tao Liu wen-Ting He School of Basic Medical Sciences Lanzhou UniversityLanzhou 730000Gansu ProvinceChina Digestive System Tumor Prevention and Treatment and Translational Medicine Engineering Innovation Center of Lanzhou University Lanzhou UniversityLanzhou 730000Gansu ProvinceChina Digestive System Tumor Translational Medicine Engineering Research Center of Gansu Province Lanzhou UniversityLanzhou 730000Gansu ProvinceChina The Second Hospital&Clinical Medical School Lanzhou UniversityLanzhou 730030Gansu ProvinceChina

BACKGROUND Gastrointestinal tumor organoids serve as an effective model for simulating cancer in vitro and have been applied in basic biology and preclinical *** over a decade of development and increasing research achievements in this field,a systematic and comprehensive analysis of the research hotspots and future trends is *** To address this problem by employing bibliometric tools to explore the publication years,countries/regions,institutions,journals,authors,keywords,and references in this *** The literature was collected from Web of Science ***-6.2R4,a widely used bibliometric analysis software package,was used for institutional analysis and reference burst *** 1.6.19 was used for journal cocitation analysis,author co-authorship and co-citation ***‘online platform for bibliometric analysis(https://***/app)’was used to assess the total number of publications and the cooperation relationships between ***,we employed the bibliometric R software package(version R.4.3.1)in R-studio,for a comprehensive scientific analysis of the *** Our analysis included a total of 1466 publications,revealing a significant yearly increase in articles on the study of gastrointestinal tumor *** United States(n=393)and Helmholtz Association(n=93)have emerged as the leading countries and institutions,respectively,in this field,with Hans Clevers and Toshiro Sato being the most contributing *** most influential journal in this field is *** most impactful reference is"Long term expansion of epithelial organs from human colon,adenoma,adenocarcinoma,and Barrett's epithelium".Keywords analysis and citation burst analysis indicate that precision medicine,disease modeling,drug development and screening,and regenerative medicine are the most cutting-edge *** focal points were further detailed based on the *** This bibl

关键词： Gastrointestinal tumor organoids Bibliometric analysis Drug development and screening Model CiteSpace

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Geochemical identification of a source rock affected by migrated hydrocarbons and its geological significance:Fengcheng Formation,southern Mahu Sag,Junggar Basin,NW China

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Petroleum Science 2024年第1期21卷 100-114页

作者： wen-Long Dang gang Gao Xin-Cai You Ke-Ting Fan Jun Wu De-wen Lei wen-Jun He Yong Tang State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum(Beijing)Beijing102249China School of GeoSciences China University of Petroleum(Beijing)Beijing102249China Exploration&Development Institute Xinjiang Oil Field CompanyKaramay834000XinjiangChina

The Fengcheng Formation is a crucial source rock and the primary reservoir for oil accumulation in the Mahu *** oils are distributed throughout the Fengcheng Formation,ranging from the edge to the interior of the sag in the southern Mahu *** crude oils originate from in-situ source rocks in shallowly buried areas and the inner deep *** migration,the crude oil from the inner deep sag affects the source rocks close to carrier beds,leading to changes in the organic geochemical characteristics of the source *** changes might alter source rock evaluations and oil-source *** on data such as total organic carbon(TOC),Rock-Eval pyrolysis of source rocks,and gas chromatography-mass spectrometry(GC-MS)of the saturated fraction,and considering the geological characteristics of the study area,we define the identification characteristics of source rock affected by migrated hydrocarbons and establish the various patterns of influence that migrated hydrocarbons have on the source rock of the Fengcheng Formation in the southern Mahu *** source rocks of the Fengcheng Formation are mostly fair to good,containing mainly Type II organic matter and being thermally mature enough to generate *** rocks affected by migrated hydrocarbons exhibit relatively high hydrocarbon contents(S1/TOC>110 mg HC/g TOC,Extract/TOC>30%,HC:hydrocarbon),relatively low Rock-Eval Tmax values,and relatively high tricyclic terpane contents with a descending and mountain-shaped ***,biomarker composition parameters indicate a higher thermal maturity than in-situ source *** a comparison of the extract biomarker fingerprints of adjacent reservoirs and mudstones in different boreholes,three types of influence patterns of migrated hydrocarbons are identified:the edge-influence of thin sandstone-thick mudstone,the mixed-influence of sandstone-mudstone interbedded,and the full-influence of thick sandstone-thin *** finding reminds

关键词： Organic geochemistry Source rock Influence of migrated hydrocarbons Fengcheng Formation Southern Mahu Sag

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