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Oil and Gas Industry Is Shifting from“Stability Amidst Change”to“Seeking Stability Within Change”——CNPC Economics&Technology Research Institute Releases 2024 Oil and Gas Industry Development Report and“15th Five-Year Plan”Outlook
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作者 Li Yi 《China Oil & Gas》 2025年第1期93-95,共3页
On January 212025,the CNPC Economics&Technology Research Institute,a national high-end think tank,released the annual report on the oil and gas industry in Beijing for the 17th consecutive year,titled the“2024 Do... On January 212025,the CNPC Economics&Technology Research Institute,a national high-end think tank,released the annual report on the oil and gas industry in Beijing for the 17th consecutive year,titled the“2024 Domestic and International Oil and Gas Industry Development Report”(referred to as the“Industry Report”). 展开更多
关键词 Economics CNPC Outlook
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New progress and future exploration targets in petroleum geological research of ultra-deep clastic rocks in Kuqa Depression,Tarim Basin,NW China
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作者 WANG Qinghua YANG Haijun YANG Wei 《Petroleum Exploration and Development》 2025年第1期79-94,共16页
Significant exploration progress has been made in ultra-deep clastic rocks in the Kuqa Depression,Tarim Basin,over recent years.A new round of comprehensive geological research has formed four new understandings:(1)Es... Significant exploration progress has been made in ultra-deep clastic rocks in the Kuqa Depression,Tarim Basin,over recent years.A new round of comprehensive geological research has formed four new understandings:(1)Establish structural model consisting of multi-detachment composite,multi-stage structural superposition and multi-layer deformation.Multi-stage structural traps are overlapped vertically,and a series of structural traps are discovered in underlying ultra-deep layers.(2)Five sets of high-quality large-scale source rocks of three types of organic phases are developed in the Triassic and Jurassic systems,and forming a good combination of source-reservoir-cap rocks in ultra-deep layers with three sets of large-scale regional reservoir and cap rocks.(3)The formation of large oil and gas fields is controlled by four factors which are source,reservoir,cap rocks and fault.Based on the spatial configuration relationship of these four factors,a new three-dimensional reservoir formation model for ultra-deep clastic rocks in the Kuqa Depression has been established.(4)The next key exploration fields for ultra-deep clastic rocks in the Kuqa Depression include conventional and unconventional oil and gas.The conventional oil and gas fields include the deep multi-layer oil-gas accumulation zone in Kelasu,tight sandstone gas of Jurassic Ahe Formation in the northern structural zone,multi-target layer lithological oil and gas reservoirs in Zhongqiu–Dina structural zone,lithologic-stratigraphic and buried hill composite reservoirs in south slope and other favorable areas.Unconventional oil and gas fields include deep coal rock gas of Jurassic Kezilenuer and Yangxia formations,Triassic Tariqike Formation and Middle-Lower Jurassic and Upper Triassic continental shale gas.The achievements have important reference significance for enriching the theory of ultra-deep clastic rock oil and gas exploration and guiding the future oil and gas exploration deployment. 展开更多
关键词 Tarim Basin Kuqa Depression ultra-deep layers clastic rock multi-layer structural deformation multilayered migration and accumulation new three-dimensional accumulation model
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Advancing skeletal health and disease research with single-cell RNA sequencing
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作者 Peng Lin Yi-Bo Gan +15 位作者 Jian He Si-En Lin Jian-Kun Xu Liang Chang Li-Ming Zhao Jun Zhu Liang Zhang Sha Huang Ou Hu Ying-Bo Wang Huai-Jian Jin Yang-Yang Li Pu-Lin Yan Lin Chen Jian-Xin Jiang Peng Liu 《Military Medical Research》 2025年第2期285-310,共26页
Orthopedic conditions have emerged as global health concerns,impacting approximately 1.7 billion individuals worldwide.However,the limited understanding of the underlying pathological processes at the cellular and mol... Orthopedic conditions have emerged as global health concerns,impacting approximately 1.7 billion individuals worldwide.However,the limited understanding of the underlying pathological processes at the cellular and molecular level has hindered the development of comprehensive treatment options for these disorders.The advent of single-cell RNA sequencing(scRNA-seq)technology has revolutionized biomedical research by enabling detailed examination of cellular and molecular diversity.Nevertheless,investigating mechanisms at the single-cell level in highly mineralized skeletal tissue poses technical challenges.In this comprehensive review,we present a streamlined approach to obtaining high-quality single cells from skeletal tissue and provide an overview of existing scRNA-seq technologies employed in skeletal studies along with practical bioinformatic analysis pipelines.By utilizing these methodologies,crucial insights into the developmental dynamics,maintenance of homeostasis,and pathological processes involved in spine,joint,bone,muscle,and tendon disorders have been uncovered.Specifically focusing on the joint diseases of degenerative disc disease,osteoarthritis,and rheumatoid arthritis using scRNA-seq has provided novel insights and a more nuanced comprehension.These findings have paved the way for discovering novel therapeutic targets that offer potential benefits to patients suffering from diverse skeletal disorders. 展开更多
关键词 Skeletal disorders Musculoskeletal system Single-cell RNA sequencing(scRNA-seq) Cellular heterogeneity Single cell suspension Bioinformatic analysis
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Research progress and potential of new enhanced oil recovery methods in oilfield development 被引量:4
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作者 YUAN Shiyi HAN Haishui +5 位作者 WANG Hongzhuang LUO Jianhui WANG Qiang LEI Zhengdong XI Changfeng LI Junshi 《Petroleum Exploration and Development》 SCIE 2024年第4期963-980,共18页
This paper reviews the basic research means for oilfield development and also the researches and tests of enhanced oil recovery(EOR)methods for mature oilfields and continental shale oil development,analyzes the probl... This paper reviews the basic research means for oilfield development and also the researches and tests of enhanced oil recovery(EOR)methods for mature oilfields and continental shale oil development,analyzes the problems of EOR methods,and proposes the relevant research prospects.The basic research means for oilfield development include in-situ acquisition of formation rock/fluid samples and non-destructive testing.The EOR methods for conventional and shale oil development are classified as improved water flooding(e.g.nano-water flooding),chemical flooding(e.g.low-concentration middle-phase micro-emulsion flooding),gas flooding(e.g.micro/nano bubble flooding),thermal recovery(e.g.air injection thermal-aided miscible flooding),and multi-cluster uniform fracturing/water-free fracturing,which are discussed in this paper for their mechanisms,approaches,and key technique researches and field tests.These methods have been studied with remarkable progress,and some achieved ideal results in field tests.Nonetheless,some problems still exist,such as inadequate research on mechanisms,imperfect matching technologies,and incomplete industrial chains.It is proposed to further strengthen the basic researches and expand the field tests,thereby driving the formation,promotion and application of new technologies. 展开更多
关键词 oilfield development enhanced oil recovery mature oilfield shale oil improved water flooding chemical flooding gas flooding thermal recovery
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Research on the solid particle erosion wear of pipe steel for hydraulic fracturing based on experiments and numerical simulations 被引量:1
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作者 Si-Qi Yang Jian-Chun Fan +7 位作者 Ming-Tao Liu De-Ning Li Jun-Liang Li Li-Hong Han Jian-Jun Wang Shang-Yu Yang Si-Wei Dai Lai-Bin Zhang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第4期2779-2792,共14页
Erosion wear is a common failure mode in the oil and gas industry.In the hydraulic fracturing,the fracturing pipes are not only in high-pressure working environment,but also suffer from the impact of the high-speed so... Erosion wear is a common failure mode in the oil and gas industry.In the hydraulic fracturing,the fracturing pipes are not only in high-pressure working environment,but also suffer from the impact of the high-speed solid particles in the fracturing fluid.Beneath such complex conditions,the vulnerable components of the pipe system are prone to perforation or even burst accidents,which has become one of the most serious risks at the fracturing site.Unfortunately,it is not yet fully understood the erosion mechanism of pipe steel for hydraulic fracturing.Therefore,this article provides a detailed analysis of the erosion behavior of fracturing pipes under complex working conditions based on experiments and numerical simulations.Firstly,we conducted erosion experiments on AISI 4135 steel for fracturing pipes to investigate the erosion characteristics of the material.The effects of impact angle,flow velocity and applied stress on erosion wear were comprehensively considered.Then a particle impact dynamic model of erosion wear was developed based on the experimental parameters,and the evolution process of particle erosion under different impact angles,impact velocities and applied stress was analyzed.By combining the erosion characteristics,the micro-structure of the eroded area,and the micro-mechanics of erosion damage,the erosion mechanism of pipe steel under fracturing conditions was studied in detail for the first time.Under high-pressure operating conditions,it was demonstrated through experiments and numerical simulations that the size of the micro-defects in the eroded area increased as the applied stress increased,resulting in more severe erosion wear of fracturing pipes. 展开更多
关键词 Erosion wear Applied stress Particle impact dynamics Erosion mechanism
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Research advances on the mechanisms of reservoir formation and hydrocarbon accumulation and the oil and gas development methods of deep and ultra-deep marine carbonates 被引量:2
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作者 MA Yongsheng CAI Xunyu +9 位作者 LI Maowen LI Huili ZHU Dongya QIU Nansheng PANG Xiongqi ZENG Daqian KANG Zhijiang MA Anlai SHI Kaibo ZHANG Juntao 《Petroleum Exploration and Development》 SCIE 2024年第4期795-812,共18页
Based on the new data of drilling, seismic, logging, test and experiments, the key scientific problems in reservoir formation, hydrocarbon accumulation and efficient oil and gas development methods of deep and ultra-d... Based on the new data of drilling, seismic, logging, test and experiments, the key scientific problems in reservoir formation, hydrocarbon accumulation and efficient oil and gas development methods of deep and ultra-deep marine carbonate strata in the central and western superimposed basin in China have been continuously studied.(1) The fault-controlled carbonate reservoir and the ancient dolomite reservoir are two important types of reservoirs in the deep and ultra-deep marine carbonates. According to the formation origin, the large-scale fault-controlled reservoir can be further divided into three types:fracture-cavity reservoir formed by tectonic rupture, fault and fluid-controlled reservoir, and shoal and mound reservoir modified by fault and fluid. The Sinian microbial dolomites are developed in the aragonite-dolomite sea. The predominant mound-shoal facies, early dolomitization and dissolution, acidic fluid environment, anhydrite capping and overpressure are the key factors for the formation and preservation of high-quality dolomite reservoirs.(2) The organic-rich shale of the marine carbonate strata in the superimposed basins of central and western China are mainly developed in the sedimentary environments of deep-water shelf of passive continental margin and carbonate ramp. The tectonic-thermal system is the important factor controlling the hydrocarbon phase in deep and ultra-deep reservoirs, and the reformed dynamic field controls oil and gas accumulation and distribution in deep and ultra-deep marine carbonates.(3) During the development of high-sulfur gas fields such as Puguang, sulfur precipitation blocks the wellbore. The application of sulfur solvent combined with coiled tubing has a significant effect on removing sulfur blockage. The integrated technology of dual-medium modeling and numerical simulation based on sedimentary simulation can accurately characterize the spatial distribution and changes of the water invasion front.Afterward, water control strategies for the entire life cycle of gas wells are proposed, including flow rate management, water drainage and plugging.(4) In the development of ultra-deep fault-controlled fractured-cavity reservoirs, well production declines rapidly due to the permeability reduction, which is a consequence of reservoir stress-sensitivity. The rapid phase change in condensate gas reservoir and pressure decline significantly affect the recovery of condensate oil. Innovative development methods such as gravity drive through water and natural gas injection, and natural gas drive through top injection and bottom production for ultra-deep fault-controlled condensate gas reservoirs are proposed. By adopting the hierarchical geological modeling and the fluid-solid-thermal coupled numerical simulation, the accuracy of producing performance prediction in oil and gas reservoirs has been effectively improved. 展开更多
关键词 deep and ultra-deep marine carbonate mechanisms of hydrocarbon accumulation reef-beach facies high-sulfur sour gas reservoirs ultra-deep fault-controlled fractured-cavity reservoir wellbore sulfur deposition fluid-solid-thermal numerical simulation
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Research on a TOPSIS energy efficiency evaluation system for crude oil gathering and transportation systems based on a GA-BP neural network 被引量:1
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作者 Xue-Qiang Zhang Qing-Lin Cheng +2 位作者 Wei Sun Yi Zhao Zhi-Min Li 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期621-640,共20页
As the main link of ground engineering,crude oil gathering and transportation systems require huge energy consumption and complex structures.It is necessary to establish an energy efficiency evaluation system for crud... As the main link of ground engineering,crude oil gathering and transportation systems require huge energy consumption and complex structures.It is necessary to establish an energy efficiency evaluation system for crude oil gathering and transportation systems and identify the energy efficiency gaps.In this paper,the energy efficiency evaluation system of the crude oil gathering and transportation system in an oilfield in western China is established.Combined with the big data analysis method,the GA-BP neural network is used to establish the energy efficiency index prediction model for crude oil gathering and transportation systems.The comprehensive energy consumption,gas consumption,power consumption,energy utilization rate,heat utilization rate,and power utilization rate of crude oil gathering and transportation systems are predicted.Considering the efficiency and unit consumption index of the crude oil gathering and transportation system,the energy efficiency evaluation system of the crude oil gathering and transportation system is established based on a game theory combined weighting method and TOPSIS evaluation method,and the subjective weight is determined by the triangular fuzzy analytic hierarchy process.The entropy weight method determines the objective weight,and the combined weight of game theory combines subjectivity with objectivity to comprehensively evaluate the comprehensive energy efficiency of crude oil gathering and transportation systems and their subsystems.Finally,the weak links in energy utilization are identified,and energy conservation and consumption reduction are improved.The above research provides technical support for the green,efficient and intelligent development of crude oil gathering and transportation systems. 展开更多
关键词 Crude oil gathering and transportation system GA-BP neural network Energy efficiency evaluation TOPSIS evaluation method Energy saving and consumption reduction
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Insights and reviews on battery lifetime prediction from research to practice 被引量:1
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作者 Xudong Qu Dapai Shi +5 位作者 Jingyuan Zhao Manh-Kien Tran Zhenghong Wang Michael Fowler Yubo Lian Andrew FBurke 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期716-739,共24页
The rising demand for energy storage solutions,especially in the electric vehicle and renewable energy sectors,highlights the importance of accurately predicting battery health to enhance their longevity and reliabili... The rising demand for energy storage solutions,especially in the electric vehicle and renewable energy sectors,highlights the importance of accurately predicting battery health to enhance their longevity and reliability.This article comprehensively examines various methods used to forecast battery health,including physics-based models,empirical models,and equivalent circuit models,among others.It delves into the promise of data-driven prognostics,utilizing both conventional machine learning and cuttingedge deep neural network techniques.The advantages and limitations of hybrid models are thoroughly analyzed,with a focus on the benefits of integrating diverse data sources to improve prognostic precision.Through practical case studies,the article showcases the effectiveness and flexibility of these approaches.It also critically addresses the challenges encountered in applying battery health prognostics in realworld scenarios,such as issues of scalability,complexity,and data anomalies.Despite these challenges,the article underscores the emerging opportunities brought about by recent technological,academic,and research advancements.These include the development of digital twin models for batteries,the use of data-centric AI and standardized benchmarking,the potential integration of blockchain technology for enhanced data security and transparency,and the synergy between edge and cloud computing to boost data analysis and processing.The primary goal of this article is to enrich the understanding of current battery health prognostic techniques and to inspire further research aimed at overcoming existing hurdles and tapping into new opportunities.It concludes with a visionary perspective on future research directions and potential developments in this evolving field,encouraging both researchers and practitioners to explore innovative solutions. 展开更多
关键词 Batteries Lifetime HEALTH Machine learning Deep learning Field Real world
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Research progresses on cathode materials of aqueous zinc-ion batteries 被引量:2
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作者 Zengyuan Fan Jiawei Wang +3 位作者 Yunpeng Wu Xuedong Yan Dongmei Dai Xing-Long Wu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第10期237-264,I0005,共29页
Electrochemical energy storage and conversion techniques that exhibit the merits such as high energy density,rapid response kinetics,economical maintenance requirements and expedient installation procedures will hold ... Electrochemical energy storage and conversion techniques that exhibit the merits such as high energy density,rapid response kinetics,economical maintenance requirements and expedient installation procedures will hold a pivotal role in the forthcoming energy storage technologies revolution.In recent years,aqueous zinc-ion batteries(AZIBs)have garnered substantial attention as a compelling candidate for large-scale energy storage systems,primarily attributable to their advantageous featu res encompassing cost-effectiveness,environmental sustainability,and robust safety profiles.Currently,one of the primary factors hindering the further development of AZIBs originates from the challenge of cathode materials.Specifically,the three mainstream types of mainstream cathode materials,in terms of manganese-based compounds,vanadium-based compounds and Prussian blue analogues,surfer from the dissolution of Mn~(2+),in the low discharge voltage,and the low specific capacity,respectively.Several strategies have been developed to compensation the above intrinsic defects for these cathode materials,including the ionic doping,defect engineering,and materials match.Accordingly,this review first provides a systematic summarization of the zinc storage mechanism in AZIBs,following by the inherent merit and demerit of three kind of cathode materials during zinc storage analyzed from their structure characteristic,and then the recent development of critical strategies towards the intrinsic insufficiency of these cathode materials.In this review,the methodologies aimed at enhancing the efficacy of manganese-based and vanadium-based compounds are emphasis emphasized.Additionally,the article outlines the future prospective directions as well as strategic proposal for cathode materials in AZIBs. 展开更多
关键词 Aqueous zinc-ion batteries Cathode materials Optimization strategies
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Research on the Mechanism of Multi-Sensor Fusion Configuration Based on the Optimal Principle of the Vehicle
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作者 Zhao Binggen Zeng Dong +2 位作者 Lin Haoyu Qiu Xubo Hu Pijie 《汽车技术》 CSCD 北大核心 2024年第10期28-37,共10页
In order to address the issue of sensor configuration redundancy in intelligent driving,this paper constructs a multi-objective optimization model that considers cost,coverage ability,and perception performance.And th... In order to address the issue of sensor configuration redundancy in intelligent driving,this paper constructs a multi-objective optimization model that considers cost,coverage ability,and perception performance.And then,combining a specific set of parameters,the NSGA-II algorithm is used to solve the multi-objective model established in this paper,and a Pareto front containing 24 typical configuration schemes is extracted after considering empirical constraints.Finally,using the decision preference method proposed in this paper that combines subjective and objective factors,decision scores are calculated and ranked for various configuration schemes from both cost and performance preferences.The research results indicate that the multi-objective optimization model established in this paper can screen and optimize various configuration schemes from the optimal principle of the vehicle,and the optimized configuration schemes can be quantitatively ranked to obtain the decision results for the vehicle under different preference tendencies. 展开更多
关键词 Multi-sensor fusion Intelligent driving Multi-objective optimization Vehicle optimization
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Research on high energy efficiency and low bit-width floating-point type data for abnormal object detection of transmission lines
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作者 Chen Wang Guozheng Peng +2 位作者 Rui Song Jun Zhang Li Yan 《Global Energy Interconnection》 EI CSCD 2024年第3期324-335,共12页
Achieving a balance between accuracy and efficiency in target detection applications is an important research topic.To detect abnormal targets on power transmission lines at the power edge,this paper proposes an effec... Achieving a balance between accuracy and efficiency in target detection applications is an important research topic.To detect abnormal targets on power transmission lines at the power edge,this paper proposes an effective method for reducing the data bit width of the network for floating-point quantization.By performing exponent prealignment and mantissa shifting operations,this method avoids the frequent alignment operations of standard floating-point data,thereby further reducing the exponent and mantissa bit width input into the training process.This enables training low-data-bit width models with low hardware-resource consumption while maintaining accuracy.Experimental tests were conducted on a dataset of real-world images of abnormal targets on transmission lines.The results indicate that while maintaining accuracy at a basic level,the proposed method can significantly reduce the data bit width compared with single-precision data.This suggests that the proposed method has a marked ability to enhance the real-time detection of abnormal targets in transmission circuits.Furthermore,a qualitative analysis indicated that the proposed quantization method is particularly suitable for hardware architectures that integrate storage and computation and exhibit good transferability. 展开更多
关键词 Power edge Data format Quantification Compute-in-memory
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Research status and application of artificial intelligence large models in the oil and gas industry
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作者 LIU He REN Yili +6 位作者 LI Xin DENG Yue WANG Yongtao CAO Qianwen DU Jinyang LIN Zhiwei WANG Wenjie 《Petroleum Exploration and Development》 SCIE 2024年第4期1049-1065,共17页
This article elucidates the concept of large model technology,summarizes the research status of large model technology both domestically and internationally,provides an overview of the application status of large mode... This article elucidates the concept of large model technology,summarizes the research status of large model technology both domestically and internationally,provides an overview of the application status of large models in vertical industries,outlines the challenges and issues confronted in applying large models in the oil and gas sector,and offers prospects for the application of large models in the oil and gas industry.The existing large models can be briefly divided into three categories:large language models,visual large models,and multimodal large models.The application of large models in the oil and gas industry is still in its infancy.Based on open-source large language models,some oil and gas enterprises have released large language model products using methods like fine-tuning and retrieval augmented generation.Scholars have attempted to develop scenario-specific models for oil and gas operations by using visual/multimodal foundation models.A few researchers have constructed pre-trained foundation models for seismic data processing and interpretation,as well as core analysis.The application of large models in the oil and gas industry faces challenges such as current data quantity and quality being difficult to support the training of large models,high research and development costs,and poor algorithm autonomy and control.The application of large models should be guided by the needs of oil and gas business,taking the application of large models as an opportunity to improve data lifecycle management,enhance data governance capabilities,promote the construction of computing power,strengthen the construction of“artificial intelligence+energy”composite teams,and boost the autonomy and control of large model technology. 展开更多
关键词 foundation model large language mode visual large model multimodal large model large model of oil and gas industry pre-training fine-tuning
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Research on typical operating conditions of hydrogen production system with off-grid wind power considering the characteristics of proton exchange membrane electrolysis cell
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作者 Weiming Peng Yanhui Xu +4 位作者 Gendi Li Jie Song Guizhi Xu Xiaona Xu Yan Pan 《Global Energy Interconnection》 EI CSCD 2024年第5期642-652,共11页
Hydrogen energy,with its abundant reserves,green and low-carbon characteristic,high energy density,diverse sources,and wide applications,is gradually becoming an important carrier in the global energy transformation a... Hydrogen energy,with its abundant reserves,green and low-carbon characteristic,high energy density,diverse sources,and wide applications,is gradually becoming an important carrier in the global energy transformation and development.In this paper,the off-grid wind power hydrogen production system is considered as the research object,and the operating characteristics of a proton exchange membrane(PEM)electrolysis cell,including underload,overload,variable load,and start-stop are analyzed.On this basis,the characteristic extraction of wind power output data after noise reduction is carried out,and then the self-organizing mapping neural network algorithm is used for clustering to extract typical wind power output scenarios and perform weight distribution based on the statistical probability.The trend and fluctuation components are superimposed to generate the typical operating conditions of an off-grid PEM electrolytic hydrogen production system.The historical output data of an actual wind farm are used for the case study,and the results confirm the feasibility of the method proposed in this study for obtaining the typical conditions of off-grid wind power hydrogen production.The results provide a basis for studying the dynamic operation characteristics of PEM electrolytic hydrogen production systems,and the performance degradation mechanism of PEM electrolysis cells under fluctuating inputs. 展开更多
关键词 Wind power fluctuation Off-grid operation Hydrogen production by PEM electrolysis Neural network clustering Typical working conditions
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Research on Signal Extraction and Classification for Ship Sound Signal Recognition
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作者 Shuai Fang Jianhui Cui +4 位作者 Ling Yang Fanbin Meng Huawei Xie Chunyan Hou Bin Li 《哈尔滨工程大学学报(英文版)》 CSCD 2024年第4期984-995,共12页
The movements and intentions of other ships can be determined by gathering and examining ship sound signals.The extraction and analysis of ship sound signals fundamentally support the autonomous navigation of intellig... The movements and intentions of other ships can be determined by gathering and examining ship sound signals.The extraction and analysis of ship sound signals fundamentally support the autonomous navigation of intelligent ships.Mel scale frequency cepstral coefficient(MFCC)feature parameters are improved and optimized to form NewMFCC by introducing second-order difference and wavelet packet decomposition transformation methods in this paper.Transforming sound signals into a feature vector that fully describes the dynamic characteristics of ship sound signals and the high-and low-frequency information solves the problem of the inability to transport ordinary sound signals directly as signals for training in machine learning models.Radial basis function kernels are used to conduct support vector machine classifier simulation experiments.Five types of sound signals,namely,one type of ship sound signals and four types of interference sound signals,are categorized and identified as classification targets to verify the feasibility of the classification of ship sound signals and interference signals.The proposed method improves classification accuracy by approximately 15%. 展开更多
关键词 Ship signal identification Signal extraction Automatic classification Intelligent ships Support vector machine
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Evaluation Test Research of DR Inspection System for Circumferential Welds in Long Distance Pipeline
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作者 WANG Changjiang WANG Xue +4 位作者 ZHANG Shimin ZHAO Yan LYU Xinyu ZHONG Qian ZHOU Guangyan 《材料导报》 EI CAS CSCD 北大核心 2024年第22期223-229,共7页
Digital radiographic(DR)testing equipment has been widely promoted and applied in the inspection of circumferential welds in oil and gas pipelines.In order to establish a comprehensive quality control system for digit... Digital radiographic(DR)testing equipment has been widely promoted and applied in the inspection of circumferential welds in oil and gas pipelines.In order to establish a comprehensive quality control system for digital radiographic testing and fully evaluate the integrated system inspection ability of equipment,personnel,and processes,a scientific and standardized evaluation method to the system is very necessary.Here investigates the precedents of relevant non-destructive testing evaluation methods at home and abroad,considers the testing characteristics of DR equipment,develops a complete set of DR testing system evaluation procedures.It deeply studies the adaptability methods of program processes from defect production to slicing processing and data statistical calculation for digital radiographic testing evaluation.To check the repeatability and reliability of the detectable system,five process welds with 200 real metallographic defects were fabricated in the laboratory.From the detected results,the DR system has good repeatability in image quality,and the detectable defect size reaches 0.85 mm under achieving 90%detection probability at a confidence level of 95%,the error of detected defect length is±2 mm,and the error of detected defect localization is±5 mm.The qualitative and quantitative detection of defects are accurate and reliable.The test further confirmed the reliable detection ability of the DR detection system,and fully validated the scientific and practical evaluation method designed.The research on the evaluation test method can serve as an important link in the quality control system for the on-site application of digital ray equipment in long-distance pipelines.The designed program,test,and evaluation content can serve as an important basis for the formulation of relevant specifications or standards. 展开更多
关键词 digital ray evaluation test REPEATABILITY RELIABILITY
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Research on casing deformation prevention technology based on cementing slurry system optimization
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作者 Yan Yan Meng Cai +3 位作者 Wen-Hai Ma Xiao-Chuan Zhang Li-Hong Han Yong-Hong Liu 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期1231-1240,共10页
The casing deformation prevention technology based on the optimization of cement slurry is proposed to reduce the casing deformation of shale oil and gas wells during hydraulic fracturing. In this paper, the fracture ... The casing deformation prevention technology based on the optimization of cement slurry is proposed to reduce the casing deformation of shale oil and gas wells during hydraulic fracturing. In this paper, the fracture mechanism of hollow particles in cement sheath was firstly analyzed by discrete element method, and the effect of hollow particles in cement on casing deformation was investigated by laboratory experiment method. Finally, field test was carried out to verify the improvement effect of the casing deformation based on cement slurry modification. The results show that the formation displacement can be absorbed effectively by hollow particles inside the cement transferring the excessive deformation away from casing. The particles in the uncemented state provide deformation space during formation slipping. The casing with diameter of 139.7 mm could be passed through by bridge plug with the diameter of 99 mm when the mass ratio of particle/cement reaches 1:4. According to the field test feedback, the method based on optimization of cement slurry can effectively reduce the risk of casing deformation, and the recommended range of hollow microbeads content in the cement slurry is between 15% and 25%. 展开更多
关键词 Cement slurry Hollow ceramsite Casing deformation Formation slip Field test
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Research progresses in geological theory and key exploration areas of coal-formed gas in China
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作者 ZHAO Zhe YANG Wei +7 位作者 ZHAO Zhenyu XU Wanglin GONG Deyu JIN Hui SONG Wei LIU Gang ZHANG Chunlin HUANG Shipeng 《Petroleum Exploration and Development》 2024年第6期1435-1450,共16页
Based on the research progress of the geological theory of coal-formed gas,the contributions of coal-formed gas to the natural gas reserves and production in China and to the development of natural gas in major gas-pr... Based on the research progress of the geological theory of coal-formed gas,the contributions of coal-formed gas to the natural gas reserves and production in China and to the development of natural gas in major gas-producing basins are analyzed,and the key favorable exploration zones for coal-formed gas in China are comprehensively evaluated.The following results are obtained.First,coal measures are good gas source rocks,and hydrocarbon generation from coal measure was dominated by gas,followed by oil.Second,a natural gas genetic identification index system based on stable isotopes,light hydrocarbon components,and biomarkers is established.Third,the quantitative and semi-quantitative factors controlling the formation of large gas fields,represented by the indicator of gas generation intensity greater than 20×10^(8) m^(3)/km^(2),are identified to guide the discovery of large gas fields in China.Fourth,coal-formed gas is the major contributor to the current natural gas reserves and production of China,both accounting for over 55%.The high proportion of coal-formed gas has enabled the Tarim,Sichuan and Ordos basins to be the major gas production areas in China.Fifth,coal rock gas is an important field for future exploration of coal-formed gas,and key zones include the Carboniferous Benxi Formation(Fm.)in the Wushenqi-Mizhi area of the Ordos Basin,the Permian Longtan Fm.in central-southern Sichuan Basin,the Jurassic Xishanyao Fm.in the southern margin and Luliang uplift of the Junggar Basin.Sixth,tight gas is the main area for increasing reserves and production,and the favorable exploration zones include the Carboniferous-Permian in southern Ordos Basin and the Bohai Bay Basin,and the Triassic Xujiahe Fm.in the transition zone between central and western Sichuan Basin.Seventh,the Jurassic in the southern margin of the Junggar Basin is a key favorable exploration zone for subsequent investigation of conventional coal-formed gas.These insights have valuable theoretical and practical significance for further developing and improving the theory of coal-formed gas,and guiding the exploration of coal-formed gas fields in China. 展开更多
关键词 coal-formed gas geological theory Tarim Basin Ordos Basin Junggar Basin Sichuan Basin hydrocarbon generation characteristics genetic identification large gas field favorable exploration zone
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Connotation and research strategy of the whole petroleum system
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作者 SONG Yan JIA Chengzao +2 位作者 JIANG Lin MA Xingzhi SHAO Xindi 《Petroleum Exploration and Development》 2024年第6期1386-1401,共16页
Traditional petroleum system theories emphasize the restoration of the accumulation process from“source”to“trap”.The main oil and gas resources in the concept are conventional oil and gas,lacking the concept and r... Traditional petroleum system theories emphasize the restoration of the accumulation process from“source”to“trap”.The main oil and gas resources in the concept are conventional oil and gas,lacking the concept and research of unconventional oil and gas enrichment mechanism.The whole petroleum system is developed from the traditional petroleum system.Combined with unconventional oil and gas exploration practices and discoveries such as shale oil and gas,the whole petroleum system adds the research content of unconventional oil and gas.Although the study of the whole petroleum system is still in three aspects:geological elements,dynamic evolution and oil and gas distribution,its research ideas and research contents are very different,including the following three aspects.(1)In terms of geological elements,the traditional petroleum system studies the characteristics of source rocks and hydrocarbon generation evolution,and the reservoir properties,traps,migration and preservation conditions of conventional oil and gas.On the basis of the above research,the whole petroleum system has increased the quantitative evaluation of retained hydrocarbons,unconventional reservoir characterization,source reservoir configuration and other research contents.(2)In terms of dynamic evolution,the petroleum system studies the matching between the evolution of conventional oil and gas source rocks and the formation period of traps,while the whole petroleum system has increased the research content of the matching of unconventional reservoir densification and oil and gas charging,and the later transformation of unconventional oil and gas reservoirs.(3)In terms of oil and gas distribution,the petroleum system takes buoyancy-drived accumulation mechanism as the core to study the migration,accumulation and distribution of conventional oil and gas.The whole petroleum system adds unconventional oil and gas self-sealing accumulation mechanism and conventional-unconventional oil and gas distribution sequence,so as to determine the oil and gas distribution characteristics of the whole petroleum system. 展开更多
关键词 whole petroleum system conventional-unconventional oil and gas research strategy geological elements dynamic evolution distribution sequence
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纸机干燥通风系统现状及研究展望,第1部分:装备与技术
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作者 尹勇军 李博伦 +4 位作者 ZHAO Joe R.H. 汪滨 沈林 SONG Chen 王双飞 《中国造纸》 北大核心 2025年第2期132-141,共10页
通风系统影响干燥能耗、运行成本及纸张质量等,是干燥过程优化潜力最大的操作单元。本文对干燥通风装备与技术现状及发展进行了梳理,指出高效、绿色、智能是装备与技术发展的趋势,需强化CFD仿真、数值计算等前沿技术在设备开发及性能提... 通风系统影响干燥能耗、运行成本及纸张质量等,是干燥过程优化潜力最大的操作单元。本文对干燥通风装备与技术现状及发展进行了梳理,指出高效、绿色、智能是装备与技术发展的趋势,需强化CFD仿真、数值计算等前沿技术在设备开发及性能提升的融入;指出了通风系统能耗差异大、缺乏与蒸汽冷凝水系统协同调控、调节策略不完善、关键状态参数与指标缺乏监控与评价等,需对通风与蒸汽冷凝水系统进行整体分析与设计,加强关键参数及指标监控,结合蒸发负荷变化完善通风控制。最后,提出应完善通风系统与蒸汽冷凝水系统的协同作用机理,为升级通风系统装备与技术提供理论基础。 展开更多
关键词 纸张干燥 气罩通风系统 协同调控 节能
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Bimetallic Single‑Atom Catalysts for Water Splitting
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作者 Megha A.Deshmukh Aristides Bakandritsos Radek Zbořil 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期1-45,共45页
Green hydrogen from water splitting has emerged as a critical energy vector with the potential to spearhead the global transition to a fossil fuel-independent society.The field of catalysis has been revolutionized by ... Green hydrogen from water splitting has emerged as a critical energy vector with the potential to spearhead the global transition to a fossil fuel-independent society.The field of catalysis has been revolutionized by single-atom catalysts(SACs),which exhibit unique and intricate interactions between atomically dispersed metal atoms and their supports.Recently,bimetallic SACs(bimSACs)have garnered significant attention for leveraging the synergistic functions of two metal ions coordinated on appropriately designed supports.BimSACs offer an avenue for rich metal–metal and metal–support cooperativity,potentially addressing current limitations of SACs in effectively furnishing transformations which involve synchronous proton–electron exchanges,substrate activation with reversible redox cycles,simultaneous multi-electron transfer,regulation of spin states,tuning of electronic properties,and cyclic transition states with low activation energies.This review aims to encapsulate the growing advancements in bimSACs,with an emphasis on their pivotal role in hydrogen generation via water splitting.We subsequently delve into advanced experimental methodologies for the elaborate characterization of SACs,elucidate their electronic properties,and discuss their local coordination environment.Overall,we present comprehensive discussion on the deployment of bimSACs in both hydrogen evolution reaction and oxygen evolution reaction,the two half-reactions of the water electrolysis process. 展开更多
关键词 Single-atom catalysts Single-atom dimers Hydrogen evolution Oxygen evolution Water splitting
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