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Sustainable electrochemical dearomatization for the synthesis of diverse 2,3-functionalized indolines

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Green Synthesis and Catalysis 2024年第1期5卷 25-30页

作者： Jun Chen Rong Zhang Caiyan Ma Peng Zhang Yonghong Zhang Bin Wang Fei Xue Weiwei Jin Yu Xia Chenjiang Liu Urumqi key laboratory of Green Catalysis and Synthesis Technology Key Laboratory of Oil and Gas Fine ChemicalsMinistry of Education&Xinjiang Uygur Autonomous RegionState Key Laboratory of Chemistry and Utilization of Carbon Based Energy ResourcesCollege of ChemistryCollege of Future TechnologyXinjiang UniversityUrumqi 830017China

Herein,we achieved a green and efficient dearomatization for the synthesis of 2,3-functionalized polycyclic indolines in an electrochemical *** avoiding of external oxidants and metals approach allowed various nucleophilic sources(Nu¼anilines,TMSN3 and ROH)to perform the products,representing an environmentally benign ***,the continuous flow electrosynthesis and synthetic transformations also reveal the strong practicality of electrochemistry in organic synthesis.

关键词： Green synthesis Organic electrochemistry Indole Dearomatization Cyclization

Low Resource Chinese Geological Text Named Entity Recognition Based on Prompt Learning

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Journal of Earth Science 2024年第3期35卷 1035-1043页

作者： Hang He Chao Ma Shan Ye Wenqiang Tang Yuxuan Zhou Zhen Yu Jiaxin Yi Li Hou Mingcai Hou state key laboratory of oil and gas Reservoir Geology and Exploitation Institute of Sedimentary GeologyCollege of Computer Science and Cyber SecurityChengdu University of TechnologyChengdu 610059China key laboratory of Deep-Time Geography and Environment Reconstruction and Applications of Ministry of Natural resources Chengdu University of TechnologyChengdu 610059China School of Information Engineering China University of Geosciences(Beijing)Beijing 100083China

Geological reports are a significant accomplishment for geologists involved in geological investigations and scientific research as they contain rich data and textual *** the rapid development of science and technology,a large number of textual reports have accumulated in the field of ***,many non-hot topics and non-English speaking regions are neglected in mainstream geoscience databases for geological information mining,making it more challenging for some researchers to extract necessary information from these *** Language Processing(NLP)has obvious advantages in processing large amounts of textual *** objective of this paper is to identify geological named entities from Chinese geological texts using NLP *** propose the RoBERTa-Prompt-Tuning-NER method,which leverages the concept of Prompt Learning and requires only a small amount of annotated data to train superior models for recognizing geological named entities in low-resource dataset *** RoBERTa layer captures context-based information and longer-distance dependencies through dynamic word ***,we conducted experiments on the constructed Geological Named Entity Recognition(GNER)*** experimental results show that the proposed model achieves the highest F1 score of 80.64%among the four baseline algorithms,demonstrating the reliability and robustness of using the model for Named Entity Recognition of geological texts.

关键词： Prompt Learning Named Entity Recognition(NER) low resource geological text text information mining big data geology.

Borehole stability in naturally fractured rocks with drilling mud intrusion and associated fracture strength weakening:A coupled DFN-DEM approach

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1565-1581页

作者： Yaoran Wei Yongcun Feng Zhenlai Tan Tianyu Yang Xiaorong Li Zhiyue Dai Jingen Deng College of Petroleum Engineering China University of Petroleum (Beijing)Beijing102249China state key laboratory of Petroleum resources and prospecting China University of Petroleum (Beijing)Beijing102249China College of Safety and Ocean Engineering China University of PetroleumBeijing102249China

Borehole instability in naturally fractured rocks poses significant challenges to *** mud invades the surrounding formations through natural fractures under the difference between the wellbore pressure(P w)and pore pressure(P p)during drilling,which may cause wellbore ***,the weakening of fracture strength due to mud intrusion is not considered in most existing borehole stability analyses,which may yield significant errors and misleading *** addition,only limited factors were analyzed,and the fracture distribution was *** this paper,the impacts of mud intrusion and associated fracture strength weakening on borehole stability in fractured rocks under both isotropic and anisotropic stress states are investigated using a coupled DEM(distinct element method)and DFN(discrete fracture network)*** provides estimates of the effect of fracture strength weakening,wellbore pressure,in situ stresses,and sealing efficiency on borehole *** results show that mud intrusion and weakening of fracture strength can damage the *** is demonstrated by the large displacement around the borehole,shear displacement on natural fractures,and the generation of fracture at shear *** intrusion reduces the shear strength of the fracture surface and leads to shear failure,which explains that the increase in mud weight may worsen borehole stability during overbalanced drilling in fractured formations.A higher in situ stress anisotropy exerts a significant influence on the mechanism of shear failure distribution around the ***,the effect of sealing natural fractures on maintaining borehole stability is verified in this study,and the increase in sealing efficiency reduces the radial invasion distance of drilling *** study provides a directly quantitative prediction method of borehole instability in naturally fractured formations,which can consider the discrete fracture network,mud intrusion,and as

关键词： Borehole stability Naturally fractured rocks Weakening of fracture strength Discrete fracture network Distinct element method

A 2D stability analysis of the rock surrounding underground liquified natural gas storage cavern based on COMSOL Multiphysics

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Energy Geoscience 2024年第3期5卷 351-361页

作者： Chao Zhang Pinjia Duan Yuke Cheng Na Chen Huan Huang Feng Xiong Shaoqun Dong CNOOC gas&Power Group Ltd. Beijing100028China School of Civil Engineering and Architecture Hubei University of TechnologyWuhan430068China state key laboratory of Petroleum resources and prospecting China University of Petroleum(Beijing)Beijing102249China College of Science China University of Petroleum(Beijing)Beijing102249China

Underground liquified natural gas(LNG)storage is essential in guaranteeing national energy strategic reserves,and its construction is being *** stability of surrounding rock of underground LNG storage caverns under stress-low temperature coupling effect is the key factor determining the feasibility of LNG ***,a mathematical model used for controlling the stress-low temperature coupling and the processes of rock damage evolution is given,followed by a 2-D numerical execution process of the mathematical model mentioned above described based on Comsol Multiphysics and Matlab ***,a series of 2-D simulations are performed to study the influence of LNG storage cavern layout,burial depth,temperature and internal pressure on the stability of surrounding rocks of these underground storage *** results indicate that all the factors mentioned above affect the evolution of deformation and plastic zone of surrounding *** research results contribute to the engineering design of underground LNG storage caverns.

关键词： Underground LNG storage Thermo-mechanical(TM)coupling Stability of surrounding rock Low temperature Comsol Multiphysics

New potential barite reference materials for LA-MC-ICP-MS sulfur isotope analysis with application to hydrothermal barite in the Huayangchuan deposit， western China

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Journal of Earth Science 2024年

作者： Jiali Fu Xinqian He Zhaochu Hu Shuo Yin Jian Ma Kaiyun Chen Wen Zhang National key laboratory of prospecting， Mining and Remote Sense Detecting on Uranium resources， East China University of Technology state key laboratory of Nuclear resources and Environment， East China University of Technology School of Earth Sciences， East China University of Technology state key laboratory of Geological Processes and Mineral resources， China University of Geosciences Wuhan state key laboratory of Continental Dynamics， Department of Geo logy， Northwest University

Sulfur isotopes of S-bearing materials are powerful tools to trace various geological processes and sulfur sources in earth sciences， especially in ore deposits where sulfide-sulfate pair coprecipitates widely. However， in-situ S isotope determination of barite is challenging without natural matrix-matched reference material. In this study， we present two natural barite reference materials （1-YS and 294-YS） for in-situ sulfur isotopic analysis. Independent LA-MC-ICP-MS laboratories were utilized to test the δ34S micron-scale homogeneity of 1-YS and 294-YS barites that have 2s repeatabilities of better than ±0.45 ‰ and ±0.41 ‰， respectively. Meanwhile， the in-situ analysis results are consistent with the results of the bulk analysis by GS-IRMS within uncertainty. The grand mean δ34S values of 1-YS （13.37‰ ± 0.42 ‰， 2s） and 294-YS （14.38‰ ± 0.44 ‰， 2s） are the final recommended values obtained from four independent laboratories. All the results confirm the suitability of 1-YS and 294-YS barite used as calibration materials with respect to in-situ S isotopic analysis. Moreover， the new developed barite reference materials were used as matrix-matched standard to calibrate the barite samples from the Huayangchuan carbonatite-hosted U-polymetallic deposit （Qinling orogenic belt， western China） to obtain δ34S values. Utilizing the temperature-dependent δ34S fractionation of barite-pyrite pair， we calculate the formation temperature of barite （i.e.， 506 to 537 ℃） and the δ34S value of mineralizing fluid （i.e.， -7.11‰ to -7.59 ‰） in the Huayangchuan deposit. The results indicate an involvement of sedimentary sulfur， presumably acting as a potential uranium source （e.g.， upper crustal materials） for the giant Huayangchuan deposit.

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Mechanisms of fracture propagation from multi-cluster using a phase field based HMD coupling model in fractured reservoir

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Petroleum Science 2024年第3期21卷 1829-1851页

作者： Yun-Jin Wang Bo Wang Hang Su Tu Chang Ren-Cheng Dong Li-Zhe Li Wei-Yu Tang Ting-Xue Jiang Fu-Jian Zhou state key laboratory of Petroleum resources and Engineering China University of Petroleum-BeijingBejing2249China China University of Petroleum-Beijing at Karamay Karamay834000XinjiangChina China National oil and gas Exploration and Development Corporation Ltd. Beijing100034China University of Texas at Austin United States SINOPEC Research Institute of Petroleum Engineering Beijing100101China

Natural fractures(NFs)are common in shale and tight reservoirs,where staged multi-cluster fracturing of horizontal wells is a prevalent technique for reservoir *** NFs and stress interference are recognized as significant factors affecting hydraulic fracture(HF)propagation,the combined influence of these factors remains poorly *** address this knowledge gap,a novel coupled hydromechanical-damage(HMD)model based on the phase field method is developed to investigate the propagation of multi-cluster HFs in fractured *** comprehensive energy functional and control functions are established,while incorporating dynamic fluid distribution between multiple perforation clusters and refined changes in rock mechanical parameters during hydraulic *** HMD coupled multi-cluster HF propagation model investigates various scenarios,including single HF and single NF,reservoir heterogeneity,single HF and NF clusters,and multi-cluster HFs with NF *** results show that the HMD coupling model can accurately capture the impact of approach angle(θ),stress difference and cementation strength on the interaction of HF and *** criterion of the open and cross zones is not *** NF angle(a)is not a decisive parameter to discriminate the *** to the relationship between approach angle(θ)and NF angle(a),the contact relationship of HF can be divided into three categories(θ=a,θa).The connected NF can increase the complexity of HF by inducing it to form branch fracture,resulting in a fractal dimension of HF as high as2.1280 at angles of±45°.Inter-fracture interference from the heel to the toe of HF shows the phenomenon of no,strong and weak ***,under the influence of NFs,distant HFs from the injection can become dominant ***,as a gradually increases,inter-fracture stress interference becomes the primary factor influencing HF propagation,gradually superseding the dominance of NF

关键词： HMD coupling Phase field Natural fracture Flow distribution Hydraulic fracturing Inter-fracture interference

Intricate Fault Systems in Longmenshan Structural Belt's Northern End: Exploring Structural Evolution and Seismic Rupture Behavior in the Eastern Tibetan Plateau

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Journal of Earth Science 2024年

作者： Hanyu Huang Renqi Lu Dengfa He Jinliang Gao Weikang Zhang Lingyu Kang state key laboratory of Earthquake Dynamics， Institute of Geology China Earthquake Administration state key laboratory of oil and gas Reservoir Geology and Exploitation， Institute of Sedimentary Geology， Chengdu University of Technology College of Energy resources， China University of Geosciences PetroChina Research Institute of Petroleum Exploration and Development

The Longmenshan Structural Belt on the eastern edge of the Tibetan Plateau experienced the impactful Mw 7.9 2008 Wenchuan earthquake， causing a 350 km surface rupture. Traditional models attribute this to the Beichuan and Pengguan faults， but our research reveals a complex fault system at the northern end， with inconsistencies in surface rupture， aftershock distribution， and focal mechanisms. We integrates shallow geology， active source seismic reflection， and magnetotelluric profiling to establish a deep structural model for the northern end of the Longmenshan Structural Belt. This area exhibits dominant reverse thrust nappe tectonics， and analyzing the tectonic evolution history provides insights into deformation propagation from the orogenic belt toward the Sichuan Basin. Focal mechanism analysis and relocated aftershock data reveals two distinct types of seismogenic structures in the northern end of the Longmenshan Structural Belt. In the middle to northern segments， the reverse fault type is attributed to reactivated pre-existing faults. Conversely， at the northern end， the strike-slip fault type originates from high-angle co-seismic rupture cutting through pre-existing reverse faults. This study enhances our understanding of fault complexity and seismic mechanisms in the northeastern Longmenshan Structural Belt， providing new insights into regional tectonics.

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Uncovering the largest negative carbon isotope excursion in Earth history

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Science China Earth Sciences 2024年第3期67卷 885-889页

作者： Chao LI Haiyang WANG state key laboratory of oil and gas Reservoir Geology and Exploitation Chengdu University of TechnologyChengdu 610059China Institute of Sedimentary Geology Chengdu University of TechnologyChengdu 610059China key laboratory of Deep-time Geography and Environment Reconstruction and Applications of Ministry of Natural resources Chengdu University of TechnologyChengdu 610059China International Center for Sedimentary Geochemistry and Biogeochemistry Research Chengdu University of TechnologyChengdu 610059China state key laboratory of Biogeology and Environmental Geology China University of GeosciencesWuhan 430074China

The carbon cycle plays a pivotal role in regulating Earth’s surface environment through atmospheric-oceanic acid-base and redox processes, functioning as the engine driving the evolution of our planet’s surface. A deep understanding of the carbon cycle’s evolution is thus essential for our understanding of the evolution of our planet’s habitability.

关键词： carbon planet evolution

Research Progress and Significance of Shale oil Micro-Migration

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Journal of Earth Science 2024年第5期35卷 1765-1769页

作者： Shang Xu Jie Wen Qiyang Gou Qiqi Li Bingchang Liu state key laboratory of Deep oil and gas China University of Petroleum(East China)Qingdao 266580China key laboratory of Coalbed Methane resources and Reservoir Formation Process Ministry of EducationChina University of Mining and TechnologyXuzhou 221116China

0 INTRODUCTION China's dependence on foreign crude oil exceeds 70%,posing significant challenges to national energy ***,traditional,easily discoverable conventional oil exploration targets are increasingly *** an important strategic replacement resource,shale oil plays an indispensable role in safeguarding national energy security and has gradually become a hotspot in the oil and gas exploration sector.

关键词： shale strategic indispensable