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Visible-light-promoted multi-component carbene transfer reactions of diazo compounds via ring-opening of cyclic ethers
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作者 Feng Zhao Hongyu Ding +4 位作者 Ting Sun Chao Shen Zu-Li Wang Wei Wei Dong Yi 《Chinese Chemical Letters》 2026年第2期206-217,共12页
Carbenes as one of the most important class of intermediates have been widely utilized in various organic synthetic transformations.Carbene insertion-initiated ring-opening reactions of cyclic ethers offer a valuable ... Carbenes as one of the most important class of intermediates have been widely utilized in various organic synthetic transformations.Carbene insertion-initiated ring-opening reactions of cyclic ethers offer a valuable strategy for constructing new carbon-oxygen bonds.In comparison with traditional thermal or metal-mediated carbene transfer reactions,visible-light-promoted multi-component reaction strategy provides a mild and eco-friendly approach to access densely functionalized molecules.Recently,visible-light-induced multi-component carbene transfer reactions of diazo compounds have been rapidly developed and attracted a great deal of research interest of chemists owing to their advantages of simple operation,mild condition,high atom economy and rich structural diversity.This paper summarizes the recent research progress on the visible-light-promoted multi-component carbene transfer reactions of diazo compounds via ring-opening of cyclic ethers with various nucleophiles.The reaction patterns of different nucleophiles and their corresponding mechanism are described in this review.The future research direction and challenges in this area are also discussed. 展开更多
关键词 VISIBLE-LIGHT multi-component reaction Carbene insertion Diazo compounds Ring-opening reaction
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Geochemistry,possible origin and exploration potential of crude oils from Neogene Shawan Formation in the Chepaizi Uplift,Junggar Basin(NW China)based on biomarker recovery method
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作者 Chen-yu Wang Xiang-chun Chang +4 位作者 You-de Xu Bing-bing Shi Tian-chen Ge Wei-zheng Gao Lei Su 《China Geology》 2026年第1期86-101,共16页
The Neogene Shawan Formation in the Chepaizi Uplift of the Junggar Basin(NW China)has obtained high oil flow,demonstrating a good potential for oil and gas exploration.The multi-source hydrocarbon generation backgroun... The Neogene Shawan Formation in the Chepaizi Uplift of the Junggar Basin(NW China)has obtained high oil flow,demonstrating a good potential for oil and gas exploration.The multi-source hydrocarbon generation background and strong tectonic activity have led to the simultaneous production of heavy oil and light oil from multi-layer in the area,which makes it very difficult to identify oil origins,presently,the hot debate on the oil origins needs to be clarified.In this paper,due to the selective consumption of different types of compounds in crude oils by severe and intense biodegradation,the commonly used oilsource correlation tools are ineffective or may produce misleading results,this study adopted a biomarker recovery method based on the principle of mass conservation that uses the sum of the mass of the residual biomarkers and their corresponding biodegradation products to obtain the mass of the original biomarkers,improving the reliability of oil origins determination.Based on the nature and occurrence of crude oils,the investigated oils are subdivided into three types,Group A,Group B and Group C.Group A,light oils occurred mainly in lower structure Neogene Shawan Formation in the western Chepaizi Uplift,while Group B,heavy oils occurred mainly in higher structure Neogene Shawan Formation in the western Chepaizi Uplift.The two types of crude oils may come from the mixed source of Jurassic Badaowan Formation source rocks(J_(1)b)and Paleogene Anjihaihe Formation source rocks(E_(2-3)a)in the Sikeshu Sag,and Jurassic Badaowan Formation source rocks(J_(1)b)are the main source of crude oils.Group C,heavy oils occurred mainly in Neogene Shawan Formation in the eastern Chepaizi Uplift,showing good correlation with the Permian(P_(1)f and P_(2)w)source rocks in the Shawan Sag.At the same time,by combining stable carbon isotope and parameters related to triaromatic steroids,the accuracy of the oilsource correlation results by biomarker recovery method was further verified. 展开更多
关键词 Biomarker recovery Oil-source correlation Stable carbon isotope Heavy and light oil identify Oil-gas exploration potential Chepaizi Uplift Neogene Shawan Formation Petroleum exploration engineering Junggar Basin
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AI and ML in groundwater exploration and water resources management:Concepts,methods,applications,and future directions
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作者 Adla Andalu MGopal Naik Sandeep Budde 《Journal of Groundwater Science and Engineering》 2026年第1期100-122,共23页
The integration of Artificial Intelligence(AI)and Machine Learning(ML)into groundwater exploration and water resources management has emerged as a transformative approach to addressing global water challenges.This rev... The integration of Artificial Intelligence(AI)and Machine Learning(ML)into groundwater exploration and water resources management has emerged as a transformative approach to addressing global water challenges.This review explores key AI and ML concepts,methodologies,and their applications in hydrology,focusing on groundwater potential mapping,water quality prediction,and groundwater level forecasting.It discusses various data acquisition techniques,including remote sensing,geospatial analysis,and geophysical surveys,alongside preprocessing methods that are essential for enhancing model accuracy.The study highlights AI-driven solutions in water distribution,allocation optimization,and realtime resource management.Despite their advantages,the application of AI and ML in water sciences faces several challenges,including data scarcity,model reliability,and the integration of these tools with traditional water management systems.Ethical and regulatory concerns also demand careful consideration.The paper also outlines future research directions,emphasizing the need for improved data collection,interpretable models,real-time monitoring capabilities,and interdisciplinary collaboration.By leveraging AI and ML advancements,the water sector can enhance decision-making,optimize resource distribution,and support the development of sustainable water management strategies. 展开更多
关键词 Artificial intelligence Machine learning Groundwater exploration Hydrological modeling Remote sensing applications Water resources management
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Noise-driven enhancement for exploration:Deep reinforcement learning for UAV autonomous navigation in complex environments
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作者 Haotian ZHANG Yiyang LI +1 位作者 Lingquan CHENG Jianliang AI 《Chinese Journal of Aeronautics》 2026年第1期454-471,共18页
Unmanned Aerial Vehicle(UAV)plays a prominent role in various fields,and autonomous navigation is a crucial component of UAV intelligence.Deep Reinforcement Learning(DRL)has expanded the research avenues for addressin... Unmanned Aerial Vehicle(UAV)plays a prominent role in various fields,and autonomous navigation is a crucial component of UAV intelligence.Deep Reinforcement Learning(DRL)has expanded the research avenues for addressing challenges in autonomous navigation.Nonetheless,challenges persist,including getting stuck in local optima,consuming excessive computations during action space exploration,and neglecting deterministic experience.This paper proposes a noise-driven enhancement strategy.In accordance with the overall learning phases,a global noise control method is designed,while a differentiated local noise control method is developed by analyzing the exploration demands of four typical situations encountered by UAV during navigation.Both methods are integrated into a dual-model for noise control to regulate action space exploration.Furthermore,noise dual experience replay buffers are designed to optimize the rational utilization of both deterministic and noisy experience.In uncertain environments,based on the Twin Delay Deep Deterministic Policy Gradient(TD3)algorithm with Long Short-Term Memory(LSTM)network and Priority Experience Replay(PER),a Noise-Driven Enhancement Priority Memory TD3(NDE-PMTD3)is developed.We established a simulation environment to compare different algorithms,and the performance of the algorithms is analyzed in various scenarios.The training results indicate that the proposed algorithm accelerates the convergence speed and enhances the convergence stability.In test experiments,the proposed algorithm successfully and efficiently performs autonomous navigation tasks in diverse environments,demonstrating superior generalization results. 展开更多
关键词 Action space exploration Autonomous navigation Deep reinforcement learning Twin delay deep deterministic policy gradient Unmanned aerial vehicle
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2025 global progress in rare earth exploration
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作者 Hui Guo Jie Meng +2 位作者 Ya-ping Li Bo-ran Guo Zi-guo Hao 《China Geology》 2026年第1期221-226,共6页
In 2025,the global rare earth exploration and development sector achieved breakthroughs across multiple fronts.Projects advanced intensively across the Americas,Oceania,Africa,and Europe,with significant growth in res... In 2025,the global rare earth exploration and development sector achieved breakthroughs across multiple fronts.Projects advanced intensively across the Americas,Oceania,Africa,and Europe,with significant growth in resources,continuous emergence of new deposits,and strong impetus injected into the industry by technological innovation and policy support.The global rare earth resource supply pattern was further optimized (Table 1).1.Fruitful results in resource growth and new deposit discoveriesBrazil emerged as a core region for resource growth.The Colossus rare earth deposit saw a 150%increase in resources and announced its first reserve estimate.The Caldeira rare earth deposit’s resource estimate grew by 50%.The combined ore resources in the Caladão rare earth deposit’s Zones A and B reached 5.72×10~8 tonnes,with a total rare earth oxide(TREO) grade of 0.1506%,concurrently hosting 2.29×10~4tonnes of gallium metal resources. 展开更多
关键词 technological innovation new deposit discoveries rare earth policy supportthe rare earth resource supply pattern resource growth rare earth exploration development policy support
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Application of multi-component joint inversion in oil and gas exploration:A case study of reservoir and gas saturation prediction of the Xujiahe formation in the PLN area of the central Sichuan Basin
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作者 Wang Dong He Zhen-Hua +4 位作者 Wang Xu-Ben Li Le Yang Hai-Tao Fu Zhi-Guo Wang Hong-Yan 《Applied Geophysics》 SCIE CSCD 2020年第5期879-889,905,共12页
Multi-component seismic exploration is an important technique in the utilization of P-waves and converted S-waves for oil and gas exploration.It has unique advantages in the structural imaging of gas zones,reservoir p... Multi-component seismic exploration is an important technique in the utilization of P-waves and converted S-waves for oil and gas exploration.It has unique advantages in the structural imaging of gas zones,reservoir prediction,lithology,and gas-water identifi cation,and the development direction and degree of fractures.Multi-component joint inversion is one of the most important steps in multi-component exploration.In this paper,starting from the basic principle of multi-component joint inversion,the diff erences between the method and single P-wave inversion are introduced.Next,the technique is applied to the PLN area of the Sichuan Basin,and the P-wave impedance,S-wave impedance,and density are obtained based on multi-component joint inversion.Through the velocity and lithology,porosity,and gas saturation fi tting formulas,prediction results are calculated,and the results are analyzed.Finally,multi-component joint inversion and single P-wave inversion are compared in eff ective reservoir prediction.The results show that multi-component joint inversion increases the constraints on the inversion conditions,reduces the multi-solution of a single P-wave inversion,and is more objective and reliable for the identification of reservoirs,effectively improving the accuracy of oil and gas reservoir prediction and development. 展开更多
关键词 multi-component joint inversion lithology identifi cation POROSITY gas saturation reservoir prediction
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Bubble Theory and its Applications in Underwater Explosion, Marine Cavitation, and Seismic Exploration 被引量:1
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作者 Runze Xu Shiping Wang +1 位作者 Hemant J.Sagar Haikun Wang 《哈尔滨工程大学学报(英文版)》 2025年第2期255-284,共30页
Bubbles play crucial roles in various fields,including naval and ocean engineering,chemical engineering,and biochemical engineering.Numerous theoretical analyses,numerical simulations,and experimental studies have bee... Bubbles play crucial roles in various fields,including naval and ocean engineering,chemical engineering,and biochemical engineering.Numerous theoretical analyses,numerical simulations,and experimental studies have been conducted to reveal the mysteries of bubble motion and its mechanisms.These efforts have significantly advanced research in bubble dynamics,where theoretical study is an efficient method for bubble motion prediction.Since Lord Rayleigh introduced the theoretical model of single-bubble motion in incompressible fluid in 1917,theoretical studies have been pivotal in understanding bubble dynamics.This study provides a comprehensive review of the development and applicability of theoretical studies in bubble dynamics using typical theoretical bubble models across different periods as a focal point and an overview of bubble theory applications in underwater explosion,marine cavitation,and seismic exploration.This study aims to serve as a reference and catalyst for further advancements in theoretical analysis and practical applications of bubble theory across marine fields. 展开更多
关键词 Bubble theory Underwater explosion Marine cavitation Seismic exploration
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NeOR: neural exploration with feature-based visual odometry and tracking-failure-reduction policy 被引量:1
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作者 ZHU Ziheng LIU Jialing +2 位作者 CHEN Kaiqi TONG Qiyi LIU Ruyu 《Optoelectronics Letters》 2025年第5期290-297,共8页
Embodied visual exploration is critical for building intelligent visual agents. This paper presents the neural exploration with feature-based visual odometry and tracking-failure-reduction policy(Ne OR), a framework f... Embodied visual exploration is critical for building intelligent visual agents. This paper presents the neural exploration with feature-based visual odometry and tracking-failure-reduction policy(Ne OR), a framework for embodied visual exploration that possesses the efficient exploration capabilities of deep reinforcement learning(DRL)-based exploration policies and leverages feature-based visual odometry(VO) for more accurate mapping and positioning results. An improved local policy is also proposed to reduce tracking failures of feature-based VO in weakly textured scenes through a refined multi-discrete action space, keyframe fusion, and an auxiliary task. The experimental results demonstrate that Ne OR has better mapping and positioning accuracy compared to other entirely learning-based exploration frameworks and improves the robustness of feature-based VO by significantly reducing tracking failures in weakly textured scenes. 展开更多
关键词 intelligent visual agents deep reinforcement learning drl based embodied visual exploration feature based visual odometry tracking failure reduction policy neural exploration deep reinforcement learning
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Scope,nature,and exploration significance of Ordos Basin during geological historical periods,NW China 被引量:1
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作者 HE Dengfa CHENG Xiang +10 位作者 ZHANG Guowei ZHAO Wenzhi ZHAO Zhe LIU Xinshe BAO Hongping FAN Liyong ZOU Song KAI Baize MAO Danfeng XU Yanhua CHENG Changyu 《Petroleum Exploration and Development》 2025年第4期855-871,共17页
Based on the analysis of surface geological survey,exploratory well,gravity-magnetic-electric and seismic data,and through mapping the sedimentary basin and its peripheral orogenic belts together,this paper explores s... Based on the analysis of surface geological survey,exploratory well,gravity-magnetic-electric and seismic data,and through mapping the sedimentary basin and its peripheral orogenic belts together,this paper explores systematically the boundary,distribution,geological structure,and tectonic attributes of the Ordos prototype basin in the geological historical periods.The results show that the Ordos block is bounded to the west by the Engorwusu Fault Zone,to the east by the Taihangshan Mountain Piedmont Fault Zone,to the north by the Solonker-Xilamuron Suture Zone,and to the south by the Shangnan-Danfeng Suture Zone.The Ordos Basin boundary was the plate tectonic boundary during the Middle Proterozoic to Paleozoic,and the intra-continental deformation boundary in the Meso-Cenozoic.The basin survived as a marine cratonic basin covering the entire Ordos block during the Middle Proterozoic to Ordovician,a marine-continental transitional depression basin enclosed by an island arc uplift belt at the plate margin during the Carboniferous to Permian,a unified intra-continental lacustrine depression basin in the Triassic,and an intra-continental cratonic basin circled by a rift system in the Cenozoic.The basin scope has been decreasing till the present.The large,widespread prototype basin controlled the exploration area far beyond the present-day sedimentary basin boundary,with multiple target plays vertically.The Ordos Basin has the characteristics of a whole petroleum(or deposition)system.The Middle Proterozoic wide-rift system as a typical basin under the overlying Phanerozoic basin and the Cambrian-Ordovician passive margin basin and intra-cratonic depression in the deep-sited basin will be the important successions for oil and gas exploration in the coming years. 展开更多
关键词 basin boundary prototype basin tectonic attribute energy and ore deposit superimposed basin whole petroleum system oil and gas exploration area Ordos Basin
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Newly Discovered High-Sulfidation Mineralization in the Yueyang Silver-Polymetallic Deposit,Zijinshan Ore Field,and Implications for Mineral Exploration 被引量:1
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作者 Jieyi Li Wenyuan Liu +4 位作者 Hua Long Jingwen Chen Jianhuan Qiu Xiaodan Lai Guiqing Xie 《Journal of Earth Science》 2025年第3期1309-1314,共6页
The Zijinshan ore field located in southwestern Fujian Province,China,is a representative porphyry-epithermal ore system hosting diverse mineralization types(Mao et al.,2013).The ore field comprises of the Zijinshan h... The Zijinshan ore field located in southwestern Fujian Province,China,is a representative porphyry-epithermal ore system hosting diverse mineralization types(Mao et al.,2013).The ore field comprises of the Zijinshan highsulfidation Cu-Au deposit,the Luoboling porphyry Cu-Mo deposit,the transitional style Cu deposit(Longjiangting and Wuziqilong)and the Yueyang low-sulfidation Agpolymetallic deposit(Zhang,2013;Zhang et al.,2003) 展开更多
关键词 transitional style cu high sulfidation mineralization Zijinshan ore field Yueyang silver polymetallic deposit porphyry epithermal ore system ore field mineral exploration diverse mineralization types
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A Regional Structural Mapping Approach for Mineral Exploration: Application in the Southwestern Region of Burkina Faso
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作者 Kalidou Traoré Benjamin Sawadogo +4 位作者 Koffi Vincent de Paul Vodounnou Wilédio Marc-Emile Bonzi Georges Alassane Ouattara Morou François Ouédraogo Séta Naba 《Open Journal of Geology》 2025年第1期1-21,共21页
From a harmonized structural map at the scale of a portion of SW Burkina Faso (90 × 80 km2), we targeted prospective zones on the basis of structural criteria and structure-geology relationships. The map was cons... From a harmonized structural map at the scale of a portion of SW Burkina Faso (90 × 80 km2), we targeted prospective zones on the basis of structural criteria and structure-geology relationships. The map was constructed from an aeromagnetic image, and the geology was deduced from old geological maps. The procedure involved extracting the magnetic fabric and deducing the deformation gradients, which led to the identification of shear zones. Analysis and interpretation of the structural geometry of the obtained structural pattern led us to target areas of interference between structures or geology-structures interplays, which are conducive to the deposition of metallic elements. The subsequent overlay of known gold prospects and deposits documented in the region revealed the validity of the predefined prospects. This result reinforces the applicability of the methodology as a first-order regional approach to mineral exploration. 展开更多
关键词 Magnetic Fabric Shear Zones TARGETING Gold Mining exploration sWAC Burkina Faso
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After a Decade of Perseverance,Setting Forth Again with Renewed Hope--Documentary of Exploration and Research in the Bogda Mountains of Tajikistan
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作者 Han Zhixiong Li Meng Gu Yanbin 《China Oil & Gas》 2025年第3期79-81,共3页
In mid-May,good news came from Tajikistan,the country of high mountains.The Tajikistan Bogda Mountain geological exploration and sampling project,which had been dormant for over a decade,achieved a key breakthrough af... In mid-May,good news came from Tajikistan,the country of high mountains.The Tajikistan Bogda Mountain geological exploration and sampling project,which had been dormant for over a decade,achieved a key breakthrough after years of careful research,multi-party collaboration,and optimization of various plans,launching a new round of field exploration and testing work. 展开更多
关键词 Bogda Mountains breakthrough sampling project TAJIKISTAN field exploration RESEARCH PERSEVERANCE geological exploration
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Integrated Geology-Geophysics Exploration of Rare Metal Deposits in the Yidun Island Arc Collisional Orogen
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作者 Yang rong Peng yu +6 位作者 Qing li Liu Qian-kun Hao Xue-feng Wu han Fan jun-bo Chen hong-juan Yang tao 《Applied Geophysics》 2025年第4期1284-1296,1498,1499,共15页
The Late Yanshanian granite belt in the Yidun Island Arc of western Sichuan constitutes a critical rare metal metallogenic zone along the eastern margin of the Tibetan Plateau,yet its deep-seated resource distribution... The Late Yanshanian granite belt in the Yidun Island Arc of western Sichuan constitutes a critical rare metal metallogenic zone along the eastern margin of the Tibetan Plateau,yet its deep-seated resource distribution has remained poorly understood.Focusing on the northern contact zone of Hagala rock mass,this study innovatively integrates geological mapping,high-power induced polarization(IP)sounding(AB/2=1500m,MN=20m),and 3D modeling to systematically constrain the spatial architecture and resource potential of deep-seated ore bodies.Key findings include:(1)Surface discovery of 12 NW-trending pegmatitetype Nb-Ta-Li-Be veins,with the No.3 principal vein exhibiting maximum dimensions(850m length×5-15m width)and average grades of 0.031%Ta_(2)O_(5)and 0.017%Nb_(2)O_(5)-significantly exceeding industrial thresholds(0.012%),while Li_(2)O(0.55%)and Rb_(2)O(0.24%)reach cutoff grades;(2)IP sounding reveals spatial correlation between deep high-resistivity anomalies(4,684Ω·m)and low polarization rates(1.28%),with 3D inversion demonstrating NE-dipping extensions exceeding 800m depth,establishing a geometrically constrained mineralization model of 2.28 million m^(3)volume;(3)Resource estimates for the No.3 vein yield 35,000 tonnes Li_(2)O and 15,000 tonnes Rb_(2)O,with 1,981 tonnes Ta_(2)O_(5)and 1,086 tonnes Nb_(2)O_(5)metal content,confirming large-scale rare metal deposit potential.The developed geology-geophysics collaborative exploration framework establishes a paradigm for rare metal prospecting in collisional orogenic belts. 展开更多
关键词 Yidun Island Arc Rare metals Geophysical exploration Geological mineral exploration
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Petroleum Exploration and Development achieves record-hing CiteScore in 2024 with expanding global influence
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作者 Editorial Office of Petroleum Exploration and Development 《Petroleum Exploration and Development》 2025年第3期F0002-F0002,共1页
On June 3,Scopus,a database owned by Elsevier,released CiteScore 2024 metrics for academic journal evaluation.Both the Chinese and English editions of Petroleum Exploration and Development achieved record highs in the... On June 3,Scopus,a database owned by Elsevier,released CiteScore 2024 metrics for academic journal evaluation.Both the Chinese and English editions of Petroleum Exploration and Development achieved record highs in the past year,ranking among the top in various categories.The CiteScore of the Chinese edition increased to 9.9 in 2024 from 8.4 in 2023,ranking 13th out of 330 journals in the Earth and Planetary Sciences:Geology category and 2lst out of 239 journals in the Earth and Planetary Sciences:Geotechnical Engineering and Engineering Geology category. 展开更多
关键词 DEVELOPMENT earth planetary sciences geology citescore global influence petroleum exploration petroleum exploration development geotechnical engineering
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Multi-component decompositions,linear superpositions,and new nonlinear integrable coupled KdV-type systems
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作者 Xiazhi Hao S Y Lou 《Communications in Theoretical Physics》 2025年第2期1-12,共12页
In the realm of nonlinear integrable systems,the presence of decompositions facilitates the establishment of linear superposition solutions and the derivation of novel coupled systems exhibiting nonlinear integrabilit... In the realm of nonlinear integrable systems,the presence of decompositions facilitates the establishment of linear superposition solutions and the derivation of novel coupled systems exhibiting nonlinear integrability.By focusing on single-component decompositions within the potential BKP hierarchy,it has been observed that specific linear superpositions of decomposition solutions remain consistent with the underlying equations.Moreover,through the implementation of multi-component decompositions within the potential BKP hierarchy,successful endeavors have been undertaken to formulate linear superposition solutions and novel coupled Kd V-type systems that resist decoupling via alterations in dependent variables. 展开更多
关键词 integrable system single-component decomposition multi-component decomposition linear superposition integrable coupled KdV-type system
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A facile high-efficiency preparation strategy for Al-containing multi-component boride microcrystals with superior comprehensive performance
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作者 Yong Fan Jinfeng Nie +7 位作者 Zhigang Ding Yujing Zhang Xiang Chen Wei Liu Sen Yang Sida Liu Xiangfa Liu Yonghao Zhao 《Journal of Materials Science & Technology》 2025年第1期190-203,共14页
Multi-component transition group metal borides(MMB_(2))have become a research hotspot due to their new composition design concepts and superior properties compared with conventional ceramics.Most of the current method... Multi-component transition group metal borides(MMB_(2))have become a research hotspot due to their new composition design concepts and superior properties compared with conventional ceramics.Most of the current methods,however,are complicated and time-consuming,the mass production remains a chal-lenge.Herein,we proposed a new high-efficiency strategy for synthesis of MMB_(2)using molten aluminum as the medium for the first time.The prepared Al-containing multi-component borides(TiZrHfNbTa)B_(2)microcrystals had a homogeneous composition with a hexagonal AlB_(2)structure and ultra-high hardness value of∼35.3 GPa,which was much higher than data reported in the literature and the rule of mix-ture estimations.Furthermore,combined with the First-principles calculation results,we found that the Poisson’s ratio(v)values exhibit a clearly ascending trend from 0.17 at VEC=3.5 to 0.18 at VEC=3.4,then to 0.201 at VEC=3.2 with the increasing of Al content.This indicates that the intrinsic toughness of multi-component boride microcrystals is obviously enhanced by the trace-doped Al elements.Besides,the fabricated Al-containing multi-component boride microcrystals have superior oxidation activation en-ergy and structural stability.The enhanced oxidation resistance is mainly attributed to the formation of a protective Al2 O3 oxide layer and the lattice distortion,both of which lead to sluggish diffusion of O_(2).These findings propose a new unexplored avenue for the fabrication of MMB_(2)materials with supe-rior comprehensive performance including ultra-hardness and intrinsically improved thermo-mechanical properties. 展开更多
关键词 multi-component borides First-principles calculations Crystal growth Mechanical properties Oxidation behavior
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Unlocking China’s Oil and Gas Exploration Secrets:Forging a Distinctive Path for China’s Petroleum Industry(Ⅰ)
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作者 Yang Hanfeng 《China Oil & Gas》 2025年第3期22-27,共6页
China’s energy resource endowment is characterized by being“poor in oil,scarce in gas,and rich in coal”,a fundamental national condition that determines the uniqueness of China’s energy strategy.At the beginning o... China’s energy resource endowment is characterized by being“poor in oil,scarce in gas,and rich in coal”,a fundamental national condition that determines the uniqueness of China’s energy strategy.At the beginning of the 20th century,foreign experts and scholars generally concluded and claimed that China was an“oil-poor country”lacking the geological conditions for hydrocarbon formation. 展开更多
关键词 oil exploration energy resource petroleum industry energy strategy energy resource endowment geological conditions gas exploration
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Pooling Scientific and Technological Expertise in Oil and Gas to Build an Academic Platform forEnergy:2025 New Year's Message from Petroleum Exploration and Development
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作者 Editorial Office of Petroleum Explorationand Development 《Petroleum Exploration and Development》 2025年第1期F0002-F0002,共1页
At the turn of the new spring,as we bid farewell to 2024 and welcome the Spring Festival of 2025,our entire editorial team of Petroleum Exploration and Development extends heartfelt gratitude and sincere New Year'... At the turn of the new spring,as we bid farewell to 2024 and welcome the Spring Festival of 2025,our entire editorial team of Petroleum Exploration and Development extends heartfelt gratitude and sincere New Year's greetings to our editorial board,experts,authors,readers,and friends from all fields! 展开更多
关键词 EXPERT exploration SPRING
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Tianwen-2 Sets Out for Asteroid Sampling and Comet Exploration
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作者 SONG Jianlan 《Bulletin of the Chinese Academy of Sciences》 2025年第2期87-89,共3页
Sent out at 1:31am GMT+8 on May 29 by a Long March-3B carrier rocket from the Xichang Satellite Launch Center in Sichuan province,China,Tianwen-2,the second mission of China’s Planetary Exploration Program,correctly ... Sent out at 1:31am GMT+8 on May 29 by a Long March-3B carrier rocket from the Xichang Satellite Launch Center in Sichuan province,China,Tianwen-2,the second mission of China’s Planetary Exploration Program,correctly entered the transfer trajectory toward an asteroid named 2016HO3 after flying for 18 minutes.Its solar wings unfolded properly,signaling a successful start,and primed for the next stage of its mission. 展开更多
关键词 long march b xichang satellite launch center planetary exploration asteroid sampling TIANWEN ho solar wings comet exploration
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Transparent geological exploration for intelligent and safe open-pit mining based on ambient noise seismic imaging
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作者 Li Ping-Feng Zheng Qiang-Qiang +3 位作者 Xu Ying Wei Di Qian Jia-wei Yang Bao-Ji 《Applied Geophysics》 2025年第1期12-21,231,共11页
The advancement of intelligent mining in open-pit operations has imposed higher demands on geological transparency,aiming to provide a robust foundation for intelligent drilling and charging.In this study,a linear arr... The advancement of intelligent mining in open-pit operations has imposed higher demands on geological transparency,aiming to provide a robust foundation for intelligent drilling and charging.In this study,a linear array of 120 nodal seismometers was deployed along the surfaces of the C8 and C9 platforms at Fenghuang Mountain to investigate cavities within the rock mass and prevent improper intelligent charging.The seismometers were 1 m apart along measurement lines,with a 2-m spacing between lines,and the monitoring time for each line was set at 2 h.This deployment was paired with spatial autocorrelation and station autocorrelation to analyze ambient noise seismic data and image the velocity and structure within the rock mass.The results demonstrate that the locations and sizes of cavities or loose structures can be accurately identified at the prepared excavation site.Compared with traditional geological exploration methods for openpit mines,the approach in this study off ers higher accuracy,greater efficiency,reduced labor intensity,and insensitivity to water conditions.Ambient noise seismic imaging for detecting adverse geological conditions in open-pit mines provides critical insights and references for intelligent mining advancements. 展开更多
关键词 Intelligent blasting Geological exploration Open-pit mines Ambient noise
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