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Magnetostratigraphy and paleoenvironmental record of late Cenozoic sediments in the Taiyuan Basin,North China

Journal of Palaeogeography 2024年第4期13卷 971-992页

作者： Zhi-Qiang Feng Qian LI Wei Han Kun-Yuan Ma Yong-Jiang Liu Rong-Zhu Wei Yan-Wei Du Yong Lei Guang-Hui Li college of Geoscience and geomatics engineering Taiyuan University of Technology Shanxi Institute of Geological Survey Frontiers Science Center for Deep Ocean Multispheres and Earth System Key Lab of Submarine Geoscience and Prospecting TechniquesCollege of Manine GeosciencesOcean University of China Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and Technology college of Resources and Environment Shanxi Agricultural University Department of Information engineering Shanxi University

The Taiyuan Basin is of importance for intraplate tectonic deformation in North China and contains Cenozoic strata with a maximum thickness of 3800 m.A～853.5-m-deep borehole (ZK01) with an overall core recovery rate of 85.09%was drilled at Yuci (37°35'37?N,112°39'47?E) in the central Taiyuan Basin,to obtain high-resolution records of paleomagnetism,paleoclimatic and paleoenvironmental conditions,and depositional environment of the *** obtained magnetic polarity sequence consists of 13 normal and 12 reverse zones,which correspond to C1n-C4An.2n of the geomagnetic polarity time *** data show that the evolution of ZK01 core covers the interval from 8.1 Ma to the present,and the bottoms of Pliocene,Quaternary,and Middle Pleistocene were identified in Taiyuan Basin,with a sedimentary accumulation rate ranging from 62.5 m/Ma to 175.9 m/*** data reveal that the source rocks in the study area underwent intense weathering and the sediments mainly formed in a semi-arid and oxygen-rich *** addition,paleoclimatic changes occurred at～7 Ma,3.8 Ma,and 1.7 Ma,which can be closely related to the tectonic uplift of the Loess Plateau and Tibetan Plateau,as well as the variations in the Asian monsoon and associated regional and global climatic change.

关键词： Taiyuan Basin Core sediment Magnetostratigraphy Climate change Paleoenvironment Quaternary

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Remote sensing and its applications using GNSS reflected signals:advances and prospects

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Satellite Navigation 2024年第1期5卷 10-51页

作者： Shuanggen Jin Adriano Camps Yan Jia Feng Wang Manuel Martin-Neira Feixiong Huang Qingyun Yan Shuangcheng Zhang Zhongyu Li Komi Edokossi Dongkai Yang Zhiyu Xiao Zhongmin Ma Weihua Bai Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai200030China School of Surveying and Land Information engineering Henan Polytechnic UniversityJiaozuo454003China Department of Signal Theory and Communications Technical University of CataloniaBarcelona08034Spain Department of Surveying and Geoinformatics Nanjing University of Posts and TelecommunicationsNanjing210023China School of Electronics and Information engineering Beihang UniversityBeijing100191China European Space Research and Technology Centre(ESTEC) European Space Agency2200-AGNoordwijkThe Netherlands National Space Science Center Chinese Academy of SciencesBeijing100190China School of Remote Sensing and geomatics engineering Nanjing University of Information Science and TechnologyNanjing210044China college of Geological engineering and geomatics Chang’an UniversityXi’an710054China University of Electronic Science and Technology of China Chengdu611731China

The Global Navigation Satellite Systems(GNSS),including the US’s GPS,China’s BDS,the European Union’s Galileo,and Russia’s GLONASS,offer real-time,all-weather,any-time,anywhere and high precision observations by transmitting L band signals continuously,which have been widely used for positioning,navigation and *** the development of GNSS technology,it has been found that GNSS-reflected signals can be used to detect Earth’s surface characteristics together with other signals of *** this paper,the current status and latest advances are presented on Global Navigation Satellite System-Reflectometry(GNSS-R)in theory,methods,techniques and *** developments and progresses in GNSS-R instruments,theoretical modeling,and signal processing,ground and space-/air-borne experiments,parameters retrieval(*** speed,sea surface height,soil moisture,ice thickness),sea surface altimetry and applications in the atmosphere,oceans,land,vegetation,and cryosphere are given and reviewed in ***,the challenges in the GNSS-R development of each field are also ***,the future applications and prospects of GNSS-R are discussed,including multi-GNSS reflectometry,new GNSS-R receivers,GNSS-R missions,and emerging applications,such as mesoscale ocean eddies,ocean phytoplankton blooms,microplastics detection,target recognition,river flow,desert studies,natural hazards and landslides monitoring.

关键词： GNSS Reflectometry Remote sensing Environmental change

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Incorporating metapath interaction on heterogeneous information network for social recommendation

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Frontiers of Computer Science 2024年第1期18卷 33-48页

作者： Yanbin JIANG Huifang MA Xiaohui ZHANG Zhixin LI Liang CHANG college of Computer Science and engineering Northwest Normal UniversityLanzhou 730070China Guangxi Key Lab of Multi-source Information mining and Security Guangxi Normal UniversityGuilin 541001China Guangxi Key Laboratory of Trusted Software Guilin University of Electronic TechnologyGuilin 541004China

Heterogeneous information network(HIN)has recently been widely adopted to describe complex graph structure in recommendation systems,proving its effectiveness in modeling complex graph *** existing HIN-based recommendation studies have achieved great success by performing message propagation between connected nodes on the defined metapaths,they have the following major *** works mainly convert heterogeneous graphs into homogeneous graphs via defining metapaths,which are not expressive enough to capture more complicated dependency relationships involved on the ***,the heterogeneous information is more likely to be provided by item attributes while social relations between users are not adequately *** tackle these limitations,we propose a novel social recommendation model MPISR,which models MetaPath Interaction for Social Recommendation on heterogeneous information ***,our model first learns the initial node representation through a pretraining module,and then identifies potential social friends and item relations based on their similarity to construct a unified *** then develop the two-way encoder module with similarity encoder and instance encoder to capture the similarity collaborative signals and relational dependency on different *** experiments on five real datasets demonstrate the effectiveness of our method.

关键词： heterogeneous information network social reco-mmender system metapath interaction attention mechanism

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Inertinite in coal and its geoenvironmental significance:Insights from AI and big data analysis

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Science China Earth Sciences 2024年第6期67卷 1779-1801页

作者： Longyi SHAO Jiamin ZHOU Timothy PJONES Fanghui HUA Xiaotao XU Zhiming YAN Haihai HOU Dongdong WANG Jing LU State Key Laboratory for Fine Exploration and Intelligent Development of Coal Resources and college of Geoscience and Surveying engineering China University of Miningand Technology(Beijing)Beijing 100083China School of Earth and Environmental Sciences Cardiff UniversityCardiff CF103YEWalesEngland General Prospecting Institute of China National Administration of Coal Geology Beijing 100039China Institute of Architectural engineering Weifang UniversityWeifang 261061China college of mining Liaoning Technical UniversityFuxin 123000China college of Earth Science and engineering Shandong University of Science and TechnologyQingdao 266590China

Inertinite,as an important and abundant maceral group in coal,is critical for the study of palaeowildfires and their roles in the Earth’s ***,there has been a significant amount of research on the relationship between palaeowildfire,palaeoclimate change and palaeovegetation evolution based on inertinite *** reflectance of fusinite and semifusinite has been used to estimate the combustion temperature and type of palaeowildfires,and then to evaluate the combustion characteristics of different types of *** relative abundance of inertinite can be used to estimate the atmospheric oxygen *** rapid development of artificial intelligence(AI)and online tools to search scientific databases has presented an opportunity for us to find,collect,arrange,and analyse data from the earliest to latest publications on *** data extraction tool Deep Shovel is used to collect and analyse global inertinite data from the Silurian to the *** software programs such as Gplates,ArcGIS pro and Tableau are then applied to model the relative abundance of inertinite over geological time,which can be correlated with other parameters such as atmospheric oxygen contents,plant evolution and palaeoclimate *** distribution of inertinite in coals varied over different geological periods,being typified by the“high inertinite content-high atmospheric oxygen level”period in the Permian and the“low inertinite content-low atmospheric oxygen level”period in the *** study has proposed a possible model of the positive and negative feedbacks between inertinite characteristics and palaeoenvironmental factors,and has revealed the exceptional role of inertinite in palaeoenvironmental *** research on inertinite will be focused on the integrated study of organic petrology and organic geochemistry of inertinite,the big data-driven research on the temporal and spatial distribution of the global inertinite,the exploration of the

关键词： Inertinite Palaeowildfires Atmospheric oxygen Palaeoclimates Palaeoecosystems

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开挖补偿法防控深部地下岩爆灾害——引汉济渭工程秦岭输水隧洞案例分析

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engineering 2024年第3期34卷 154-163页

作者： Jie Hu Manchao He Hongru Li Zhigang Tao Dongqiao Liu Tai Cheng Di Peng Department of Geotechnical engineering College of Civil EngineeringTongji UniversityShanghai 200092China State Key Laboratory for Geomechanics and Deep Underground engineering China University of Mining and TechnologyBeijing 100083China

Rockburst disasters occur frequently during deep underground excavation,yet traditional concepts and methods can hardly meet the requirements for support under high geo-stress ***,rockburst control remains challenging in the engineering *** this study,the mechanism of excavation-induced rockburst was briefly described,and it was proposed to apply the excavation compensation method(ECM)to rockburst ***,a field test was carried out on the Qinling Water Conveyance *** following beneficial findings were obtained:Excavation leads to changes in the engineering stress state of surrounding rock and results in the generation of excess energy DE,which is the fundamental cause of *** ECM,which aims to offset the deep excavation effect and lower the risk of rockburst,is an active support strategy based on high pre-stress *** new negative Poisson’s ratio(NPR)bolt developed has the mechanical characteristics of high strength,high toughness,and impact resistance,serving as the material basis for the *** field test results reveal that the ECM and the NPR bolt succeed in controlling rockburst disasters *** research results are expected to provide guidance for rockburst support in deep underground projects such as Sichuan-Xizang Railway.

关键词： Rockburst Excavation compensation method Pre-stressed support Negative Poisson’s ratio bolt Tunnel boring machine

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长壁放顶煤工作面沿空巷道的变形破坏机理

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Journal of Central South University 2024年第5期31卷 1542-1559页

作者：王浩森何满潮王炯王瑞明灿朱道勇马资敏 State Key Laboratory for Geomechanics and Deep Underground engineering China University of Mining&TechnologyBeijing 100083China NBK Institute of mining engineering University of British ColumbiaVancouver BC V6T 1Z4Canada mining engineering and Geology college Xinjiang Institute of EngineeringUrumqi 830023China Department of Earth Sciences University of FlorenceFirenze 50121Italy college of Water&Architectural engineering Shihezi UniversityShihezi 832003China School of Resource and Environmental engineering Shandong University of TechnologyZibo 255000China

本文利用物理和数值模型研究了长壁放顶煤工作面沿空巷道的变形和破坏机理。物理模型实验表明,长壁放顶煤工作面沿空巷道的变形破坏过程可分为四个阶段:初始变形阶段Ⅰ(相邻工作面后方-47~45 m)、快速变形阶段Ⅱ(45~150 m)、变形稳定阶... 详细信息

本文利用物理和数值模型研究了长壁放顶煤工作面沿空巷道的变形和破坏机理。物理模型实验表明,长壁放顶煤工作面沿空巷道的变形破坏过程可分为四个阶段:初始变形阶段Ⅰ(相邻工作面后方-47~45 m)、快速变形阶段Ⅱ(45~150 m)、变形稳定阶段Ⅲ(150~240 m)和压实稳定阶段IV(工作面后方240 m外)。值得注意的是,长壁放顶煤工作面沿空巷道围岩的大变形主要发生在快速变形阶段Ⅱ和变形稳定阶段Ⅲ。这主要是由沿空巷道上方的侧向悬臂梁结构旋转下沉过程中产生的应力集中造成的。因此,本文提出了一种创新方法,使用顶板预裂技术来优化巷道顶板结构,控制长壁放顶煤工作面沿空巷道围岩的大变形并自动留巷。数值模拟和现场应用表明,使用顶板预裂自动留巷技术后,长壁放顶煤工作面沿空巷道实体煤帮的支承压力、顶底板变形量和两帮变形量分别降低了6.49%、79.25%和60%。因此,顶板预裂自动留巷技术可以有效控制长壁放顶煤工作面沿空巷道的围岩大变形。本文所提出的长壁放顶煤工作面顶板预裂自动留巷技术可以为厚及特厚煤层综放工作面使用切顶卸压无煤柱自成巷技术提供参考。

关键词：物理模型实验变形机理沿空巷道顶板预裂

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Ultrathin and flexible MXene-contained electromagnetic interference shielding composite paper designed with a protective hydrogel film

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Journal of Materials Science & Technology 2024年第2期169卷 199-208页

作者： Jiasheng Wei Lei Dai Ping He Meng Zhu Feng Jiang Zhaoxiang Zhou Guiqiang Fei Tingzhou Lei college of Bioresources Chemical and Materials engineering Shaanxi University of Science and TechnologyXi’an 710021China Key Laboratory of Eco-Textiles Ministry of EducationJiangnan UniversityWuxi 214122China Zhejiang Shunpu New Material Technology Co. LtdLongyou 324404China college of Chemistry and Chemical engineering Shaanxi University of Science and TechnologyXi’an 710021China National-Local Joint engineering Research Center of Biomass Refining and High-Quality Utilization Institute of Urban and Rural MiningChangzhou UniversityChangzhou 213164China

MXene-contained paper is a good choice to design ultrathin and flexible electromagnetic interference(EMI)shielding ***,the deficiencies in strength and stability of MXene-contained paper impede its practical ***,a composite paper was proposed to address the problems,in which a filter paper was modified with a three-layer structured surface via a facile layer-by-layer coating ***,the TEMPO-oxidized cellulose nanofibers(TOCN)/cationic starch(CS)/MXene gel layer and TOCN/MXene nacre structure layer ensured the good EMI shielding and mechanical performances of the composite paper,while the uppermost TOCN/CS hydrogel film layer mainly protected *** composite paper achieved an EMI SE of 40.3 dB at a thickness of merely 0.1894 mm(SE/t value of ca.212.8 dB mm^(−1),SSE/t values of ca.13216 dB cm 2 g^(−1))and the total MXene dosage was 20 g m^(−2).Its tensile strength could be up to 11.7 MPa while the original filter paper was 6.4 *** pieces of this composite papers could be easily packed together to attain an EMI SE of nearly 70 ***,the hydrogel film layer efficiently protected the MXene and maintained the EMI shielding performance of the composite paper when immersed in different liquids including water,HCl(1 M)and ethanol,due to the dense and compact structure of hydrogel film *** work provides a practical way to develop ultrathin,flexible and durable EMI shielding materials.

关键词： MXene Electromagnetic interference shielding Nanocellulose Hydrogel

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NMR-based analysis of the effect of moisture migration on sandstone pore structure under alternating wetting and drying conditions

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International Journal of mining Science and Technology 2024年第8期34卷 1135-1150页

作者： Huasu Wang Jing Bi Yu Zhao Chaolin Wang Jiabao Ma college of Civil engineering Guizhou UniversityGuiyang 550025China

The wetting-drying(W-D)cycle is a type of water–rock *** pore structure of rock,such as shape,size,distribution and pore throat,affects fluid storage and *** theory and experimental research on the evolution characteristics of pore damage during the wet-dry erosion process are highly important for determining W-D *** mass and velocity of liquid migration are related to the pore size,porosity,fluid properties,*** data show that the water absorption quality and velocity in rocks decrease with the number of wet-dry *** the same test time,the mass and velocity of the SI water absorption method are smaller than those of the FI *** these two conditions,the amount and rate of water absorption represent the degree of water–rock *** the pore evolution during the wet-dry cycling,an equation describing the motion of liquid in porous media was derived based on the imbibition-type separation *** experimental data are in excellent agreement with the calculated values of the *** characteristics can affect the area and degree of rock deterioration as well as the development rate of pores and *** on the interaction between permeability and pores,quantitative analysis of the weakening process(local damage)of rocks under W-D cycles can provide good reference indicators for evaluating the stability of geotechnical engineering.

关键词： W-D cycle Capillary absorption Pore characteristic Fractal theory Dynamic damage model

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Multiscale modeling of gas-induced fracturing in anisotropic clayey rocks

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Journal of Rock Mechanics and Geotechnical engineering 2024年第6期16卷 2091-2110页

作者： Jianxiong Yang Jianfeng Liu Zhengyuan Qin Xuhai Tang Houquan Zhang State Key Laboratory of Hydraulics and Mountain River engineering College of Water Resource and HydropowerSichuan UniversityChengdu610042China School of Resources and Safety engineering Wuhan Institute of TechnologyWuhan430073China School of Civil engineering Wuhan UniversityWuhan430072China State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground engineering China University of Mining and TechnologyXuzhou221116China

In the context of repositories for nuclear waste,understanding the behavior of gas migration through clayey rocks with inherent anisotropy is crucial for assessing the safety of geological disposal *** primary mechanism for gas breakthrough is the opening of micro-fractures due to high gas *** occurs at gas pressures lower than the combined strength of the rock and its minimum principal stress under external loading *** investigate the mechanism of microscale mode-I ruptures,it is essential to incorporate a multiscale approach that includes subcritical microcracks in the modeling *** this contribution,we derive the model from microstructures that contain periodically distributed microcracks within a porous *** damage evolution law is coupled with the macroscopic poroelastic system by employing the asymptotic homogenization method and considering the inherent hydro-mechanical(HM)anisotropy at the *** resulting permeability change induced by fracture opening is implicitly integrated into the gas flow *** examples are presented to validate the developed model step by *** analysis of local macroscopic response is undertaken to underscore the influence of factors such as strain rate,initial damage,and applied stress,on the gas migration *** examples of direct tension tests are used to demonstrate the model’s efficacy in describing localized failure ***,the simulation results for preferential gas flow reveal the robustness of the two-scale model in explicitly depicting gas-induced fracturing in anisotropic clayey *** model successfully captures the common behaviors observed in laboratory experiments,such as a sudden drop in gas injection pressure,rapid build-up of downstream gas pressure,and steady-state gas flow following gas breakthrough.

关键词： Deep geological repositories Mode-I microcracks Time-dependent damage Fracturing process Anisotropic rock

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GNSS gyroscopes:determination of angular velocity and acceleration with very high-rate GNSS

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Satellite Navigation 2024年第1期5卷 74-90页

作者： Yun Shi Peiliang Xu Yuanming Shu Xiaolin Meng School of geomatics Xi’an University of Science and TechnologyXi’an710054People’s Republic of China Disaster Prevention Research Institute Kyoto UniversityUjiKyoto611-0011Japan college of Marine Geosciences Ocean University of ChinaQingdaoPeople’s Republic of China School of Instrument Science and engineering Southeast UniversityNanjing210096People’s Republic of China

Although global navigation satellite systems(GNSS)have been routinely applied to determine attitudes,there exists no literature on determining angular velocity and/or angular acceleration from *** by the invention of computerized accelerometers of the correspondence author and following the success of accurately recovering translational velocity and acceleration waveforms from very high-rate GNSS precise positioning by Xu and his collaborators in 2021,we propose the concept of GNSS gyroscopes and reconstruct angular velocity and acceleration from very high-rate GNSS attitudes by applying regularization under the criterion of minimum mean squared *** major results from the experiments can be summarized in the following:(i)angular velocity and acceleration waveforms computed by applying the difference methods to high-rate GNSS attitudes are too noisy and can be physically not meaningful and numerically *** same can be said about inertial measurement unit(IMU)attitudes,if IMU gyros are not of very high accuracy;(ii)regularization is successfully applied to reconstruct the high-rate angular velocity and acceleration waveforms from 50 Hz GNSS attitudes and significantly outperforms the difference methods,validating the proposed concept of GNSS *** comparing the angular velocity and acceleration results by using the difference methods and regularization,we find that the peak values of angular velocity and acceleration by regularization are much smaller by a maximum factor of 1.57 in the angular velocity to a maximum factor of 8662.53 times in the angular acceleration in the case of high-rate GNSS,and by a maximum factor of 1.26 in the angular velocity to a maximum factor of 2819.85 times in the angular acceleration in the case of IMU,respectively;and(iii)the IMU attitudes apparently lead to better regularized angular velocity and acceleration waveforms than the high-rate GNSS attitudes,which can well be explained by the fact that the

关键词： Angular velocity Angular acceleration High-rate GNSS GNSS attitudes GNSS gyroscopes Regularization

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