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Constructing long-cycling crystalline C_(3)N_(4)-based carbonaceous anodes for sodium-ion battery via N configuration control 被引量:1
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作者 Ying Wang Hongguan Li +5 位作者 Shuanlong Di Boyin Zhai Ping Niu Antonios Kelarakis Shulan Wang Li Li 《Carbon Energy》 SCIE EI CAS CSCD 2024年第1期159-171,共13页
Carbon nitrides with two-dimensional layered structures and high theoretical capacities are attractive as anode materials for sodium-ion batteries while their low crystallinity and insufficient structural stability st... Carbon nitrides with two-dimensional layered structures and high theoretical capacities are attractive as anode materials for sodium-ion batteries while their low crystallinity and insufficient structural stability strongly restrict their practical applications.Coupling carbon nitrides with conductive carbon may relieve these issues.However,little is known about the influence of nitrogen(N)configurations on the interactions between carbon and C_(3)N_(4),which is fundamentally critical for guiding the precise design of advanced C_(3)N_(4)-related electrodes.Herein,highly crystalline C_(3)N_(4)(poly(triazine imide),PTI)based all-carbon composites were developed by molten salt strategy.More importantly,the vital role of pyrrolic-N for enhancing charge transfer and boosting Na+storage of C_(3)N_(4)-based composites,which was confirmed by both theoretical and experimental evidence,was spot-highlighted for the first time.By elaborately controlling the salt composition,the composite with high pyrrolic-N and minimized graphitic-N content was obtained.Profiting from the formation of highly crystalline PTI and electrochemically favorable pyrrolic-N configurations,the composite delivered an unusual reverse growth and record-level cycling stability even after 5000 cycles along with high reversible capacity and outstanding full-cell capacity retention.This work broadens the energy storage applications of C_(3)N_(4) and provides new prospects for the design of advanced all-carbon electrodes. 展开更多
关键词 ANODE highly crystalline C_(3)N_(4) N configuration sodium-ion batteries ultra-long cyclic stability
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Engineering of geometrical configurations in dual-atom catalysts for electrocatalytic applications
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作者 Tao Zhang Yifan Liu +3 位作者 Liang Xue Jingwen Sun Pan Xiong Junwu Zhu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期273-287,共15页
Geometrical configurations play a crucial role in dual-atom catalysts(DACs)for electrocatalytic applications.Significant progress has been made to design DACs electrocatalysts with various geometri-cal configurations,... Geometrical configurations play a crucial role in dual-atom catalysts(DACs)for electrocatalytic applications.Significant progress has been made to design DACs electrocatalysts with various geometri-cal configurations,but in-depth understanding the relationship between geometrical configurations and metal-metal interaction mechanisms for designing targeted DACs is still required.In this review,the recent progress in engineering of geometrical configurations of DACs is systematically summarized.Based on the polarity of geometrical configuration,DACs can be classified into two different types that are homonuclear and heteronuclear DACs.Furthermore,with regard to the geometrical configurations of the active sites,homonuclear DACs are identified into adjacent and bridged configurations,and heteronuclear DACs can be classified into adjacent,bridged,and separated configurations.Subsequently,metal-metal interactions in DACs with different geometrical configurations are introduced.Additionally,the applications of DACs in different electrocatalytic reactions are discussed,including the oxygen reduction reaction(ORR),oxygen evolution reaction(OER),hydrogen evolution reaction(HER),and other catalysis.Finally,the future challenges and perspectives for advancements in DACs are high-lighted.This review aims to provide inspiration for the design of highly effcient DACs towards energy relatedapplications. 展开更多
关键词 Dual-atom catalysts Geometrical configurations HOMONUCLEAR HETERONUCLEAR ELECTROCATALYSIS
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Spectroscopy and molecule opacity investigation on excited states of SiS
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作者 李瑞 吕浩男 +3 位作者 桑纪群 刘晓华 梁桂颖 吴勇 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期381-387,共7页
The SiS molecule,which plays a significant role in space,has attracted a great deal of attention for many years.Due to complex interactions among its low-lying electronic states,precise information regarding the molec... The SiS molecule,which plays a significant role in space,has attracted a great deal of attention for many years.Due to complex interactions among its low-lying electronic states,precise information regarding the molecular structure of SiS is limited.To obtain accurate information about the structure of its excited states,the high-precision multireference configuration interaction(MRCI)method has been utilized.This method is used to calculate the potential energy curves(PECs)of the 18Λ–S states corresponding to the lowest dissociation limit of SiS.The core–valence correlation effect,Davidson’s correction and the scalar relativistic effect are also included to guarantee the precision of the MRCI calculation.Based on the calculated PECs,the spectroscopic constants of quasi-bound and bound electronic states are calculated and they are in accordance with previous experimental results.The transition dipole moments(TDMs)and dipole moments(DMs)are determined by the MRCI method.In addition,the abrupt variations of the DMs for the 1^(5)Σ^(+)and 2^(5)Σ^(+)states at the avoided crossing point are attributed to the variation of the electronic configuration.The opacity of SiS at a pressure of 100 atms is presented across a series of temperatures.With increasing temperature,the expanding population of excited states blurs the band boundaries. 展开更多
关键词 SIS OPACITY excited state spectroscopic constant configuration interaction
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Coordinated responses of leaf and nodule traits contribute to the accumulation of N in relay intercropped soybean
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作者 Ping Chen Qing Du +8 位作者 Benchuan Zheng Huan Yang Zhidan Fu Kai Luo Ping Lin Yilin Li Tian Pu Taiwen Yong Wenyu Yang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第6期1910-1928,共19页
Maize(Zea mays L.)-soybean(Glycine max L.Merr.)relay intercropping provides a way to enhance land productivity.However,the late-planted soybean suffers from shading by the maize.After maize harvest,how the recovery gr... Maize(Zea mays L.)-soybean(Glycine max L.Merr.)relay intercropping provides a way to enhance land productivity.However,the late-planted soybean suffers from shading by the maize.After maize harvest,how the recovery growth influences the leaf and nodule traits remains unclear.A three-year field experiment was conducted to evaluate the effects of genotypes,i.e.,supernodulating(nts1007),Nandou 12(ND12),and Guixia 3(GX3),and crop configurations,i.e.,the interspecific row spacing of 45(I45),60(I60),75 cm(I75),and sole soybean(SS),on soybean recovery growth and N fixation.The results showed that intercropping reduced the soybean total leaf area(LA)by reducing both the leaf number(LN)and unit leaflet area(LUA),and it reduced the nodule dry weight(NW)by reducing both the nodule number(NN)and nodule diameter(ND)compared with the SS.The correlation and principal component analysis(PCA)indicated a co-variability of the leaf and nodule traits in response to the genotype and crop configuration interactions.During the recovery growth stages,the compensatory growth promoted soybean growth to reduce the gaps of leaf and nodule traits between intercropping and SS.The relative growth rates of ureide(RGR_U)and nitrogen(RGR_N)accumulation were higher in intercropping than in SS.Intercropping achieved more significant sucrose and starch contents compared with SS.ND12 and GX3 showed more robust compensatory growth than nts1007 in intercropping.Although the recovery growth of relay intercropping soybean improved biomass and nitrogen accumulation,ND12 gained a more significant partial land equivalent ratio(pLER)than GX3.The I60 treatment achieved more robust compensation effects on biomass and N accumulation than the other configurations.Meanwhile,I60 showed a higher nodule sucrose content and greater shoot ureide and N accumulation than SS.Finally,intercropping ND12 with maize using an interspecific row spacing of 60 cm was optimal for both yield advantage and N accumulation. 展开更多
关键词 relay intercropping GENOTYPE crop configuration symbiotic nitrogen fixation SOYBEAN NODULE
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The preparation and properties of N-doped carbon materials and their use for sodium storage
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作者 YUAN Ren-lu HOU Ruo-yang +4 位作者 SHANG Lei LIU Xue-wei LI Ang CHEN Xiao-hong SONG Huai-he 《新型炭材料(中英文)》 SCIE EI CAS CSCD 北大核心 2024年第5期770-795,共26页
Defect engineering by heteroatom doping gives carbon materials some new characteristics such as a different electronic structure and a high electrochemical activity,making them suitable for high-performance applicatio... Defect engineering by heteroatom doping gives carbon materials some new characteristics such as a different electronic structure and a high electrochemical activity,making them suitable for high-performance applications.N-doping has been widely investigated because of its similar atom radius to carbon,high electronegativity as well as many different configurations.We summarize the preparation methods and properties of N-doped carbon materials,and discuss their possible use in sodium ion storage.The relationships between N content/configuration and crystallinity,electronic conductivity,wettability,chemical reactivity as well as sodium ion storage performance are discussed. 展开更多
关键词 N-doped carbon material N configuration Preparation method Performance Sodium storage
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Sliding and damming properties of granular debris with different geometric configurations and grain size distributions
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作者 HE Ligeng TAN Longmeng +2 位作者 YANG Xingguo ZHOU Jiawen LIAO Haimei 《Journal of Mountain Science》 SCIE CSCD 2024年第3期932-951,共20页
Granular debris plays a significant role in determining damming deposit characteristics. An indepth understanding of how variations in grain size distribution(GSD) and geometric configurations impact the behavior of g... Granular debris plays a significant role in determining damming deposit characteristics. An indepth understanding of how variations in grain size distribution(GSD) and geometric configurations impact the behavior of granular debris during the occurrence of granular debris is essential for precise assessment and effective mitigation of landslide hazards in mountainous terrains. This research aims to investigate the impact of GSD and geometric configurations on sliding and damming properties through laboratory experiments. The geometric configurations were categorized into three categories based on the spatial distribution of maximum volume: located at the front(Type Ⅰ), middle(Type Ⅱ), and rear(Type Ⅲ) of the granular debris. Our experimental findings highlight that the sliding and damming processes primarily depend on the interaction among the geometric configuration, grain size, and GSD in granular debris. Different sliding and damming mechanisms across various geometric configurations induce variability in motion parameters and deposition patterns. For Type Ⅰ configurations, the front debris functions as the critical and primary driving component, with energy dissipation primarily occurring through inter-grain interactions. In contrast, Type Ⅱ configurations feature the middle debris as the dominant driving component, experiencing hindrance from the front debris and propulsion from the rear, leading to complex alterations in sliding motion. Here, energy dissipation arises from a combination of inter-grain and grain-substrate interactions. Lastly, in Type Ⅲ configurations, both the middle and rear debris serve as the main driving components, with the rear sliding debris impeded by the front. In this case, energy dissipation predominantly results from grainsubstrate interaction. Moreover, we have quantitatively demonstrated that the inverse grading in damming deposits, where coarse grain moves upward and fine grain moves downward, is primarily caused by grain sorting due to collisions among the grains and between the grain and the base. The impact of grain on the horizontal channel further aids grain sorting and contributes to inverse grading. The proposed classification of three geometric configurations in our study enhances the understanding of damming properties from the view of mechanism, which provides valuable insights for related study about damming granular debris. 展开更多
关键词 Landslide dam Geometric configuration Energy dissipation Inverse grading Physical experiment
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Seismic fragility analysis of three-tower cable-stayed bridges with different connection configurations
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作者 Chen Chen Liu Jinlong +1 位作者 Lin Junqi Li Suchao 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第4期1009-1027,共19页
Seismic fragility analysis of three-tower cable-stayed bridges with three different structural systems,including rigid system(RS),floating system(FS),and passive energy dissipation system(PEDS),is conducted to study t... Seismic fragility analysis of three-tower cable-stayed bridges with three different structural systems,including rigid system(RS),floating system(FS),and passive energy dissipation system(PEDS),is conducted to study the effects of connection configurations on seismic responses and fragilities.Finite element models of bridges are established using OpenSees.A new ground motion screening method based on the statistical characteristic of the predominant period is proposed to avoid irregular behavior in the selection process of ground motions,and incremental dynamic analysis(IDA)is performed to develop components and systems fragility curves.The effects of damper failure on calculated results for PEDS are examined in terms of seismic response and fragility analysis.The results show that the bridge tower is the most affected component by different structural systems.For RS,the fragility of the middle tower is significantly higher than other components,and the bridge failure starts from the middle tower,exhibiting a characteristic of local failure.For FS and PEDS,the fragility of the edge tower is higher than the middle tower.The system fragility of RS is higher than FS and PEDS.Taking the failure of dampers into account is necessary to obtain reliable seismic capacity of cable-stayed bridges. 展开更多
关键词 seismic fragility cable-stayed bridge connection configuration viscous damper comparison analysis
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Distributed IRS-Aided DF Relaying Systems:Performance Analysis and Optimization
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作者 Sun Qiang Qian Panpan +3 位作者 Chen Xiaomin Ju Jinjuan Wang Jue Zhang Jiayi 《China Communications》 SCIE CSCD 2024年第6期129-145,共17页
Intelligent reflecting surface(IRS)is a newly emerged and promising paradigm to substantially improve the performance of wireless communications by constructing favorable communication channels via properly tuning mas... Intelligent reflecting surface(IRS)is a newly emerged and promising paradigm to substantially improve the performance of wireless communications by constructing favorable communication channels via properly tuning massive reflecting elements.This paper considers a distributed IRS aided decode-and-forward(DF)relaying system over Nakagami-m fading channels.Based on a tight approximation for the distribution of the received signalto-noise ratio(SNR),we first derive exact closed-form expressions of the outage probability,ergodic capacity,and energy efficiency for the considered system.Moreover,we propose the optimal IRS configuration considering the energy efficiency and pilot overhead.Finally,we compare the performance between the distributed IRS-aided DF relaying and multi-IRS-only systems,and verify the analytical results by using monte carlo simulations. 展开更多
关键词 CONFIGURATION energy efficiency ergodic capacity intelligent reflecting surface IRS outage probability
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Configuration Synthesis and Grasping Performance Analysis of Multi-Loop Coupling Capture Mechanism for Launch and Recovery of Torpedo-Shaped Autonomous Underwater Vehicle
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作者 ZHANG Guo-xing XIA Xin-lu GUO Jin-wei 《China Ocean Engineering》 SCIE EI CSCD 2024年第3期453-466,共14页
Research of capture mechanisms with strong capture adaptability and stable grasp is important to solve the problem of launch and recovery of torpedo-shaped autonomous underwater vehicles(AUVs).A multi-loop coupling ca... Research of capture mechanisms with strong capture adaptability and stable grasp is important to solve the problem of launch and recovery of torpedo-shaped autonomous underwater vehicles(AUVs).A multi-loop coupling capture mechanism with strong adaptability and high retraction rate has been proposed for the launch and recovery of torpedo-shaped AUVs with different morphological features.Firstly,the principle of capturing motion retraction is described based on the appearance characteristics of torpedo-shaped AUVs,and the configuration synthesis of the capture mechanism is carried out using the method of constrained chain synthesis.Secondly,the screw theory is employed to analyze the degree of freedom(DoF)of the capture mechanism.Then,the 3D model of the capture mechanism is established,and the kinematics and dynamics simulations are carried out.Combined with the capture orientation requirements of the capture mechanism,the statics and vibration characteristics analyses are carried out.Furthermore,considering the capture process and the underwater working environment,the motion characteristics and hydraulics characteristics of the capture mechanism are analyzed.Finally,a principle prototype is developed and the torpedo-shaped AUVs capture experiment is completed.The work provides technical reserves for the research and development of AUV capture special equipment. 展开更多
关键词 capture mechanism torpedo-shaped AUVs configuration synthesis launch and recovery grasping performance analysis
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Bound and Resonating Multiquark Configurations
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作者 Jean-Marc Richard 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第8期8-12,共5页
We review the predictions of quark models for multiquark configurations that are bound or resonant states,and compare different methods for estimating the properties of resonances.
关键词 QUARK CONFIGURATION RESONANT
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Unveiling the geometric site dependent activity of spinel Co_(3)O_(4)for electrocatalytic chlorine evolution reaction
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作者 Linke Cai Yao Liu +5 位作者 Jingfang Zhang Qiqi Jia Jiacheng Guan Hongwei Sun Yu Yu Yi Huang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期95-103,共9页
Spinel cobalt oxide(Co_(3)O_(4)),consisting of tetrahedral Co^(2+)(CoTd)and octahedral Co^(3+)(CoOh),is considered as promising earth-abundant electrocatalyst for chlorine evolution reaction(CER).Identifying the catal... Spinel cobalt oxide(Co_(3)O_(4)),consisting of tetrahedral Co^(2+)(CoTd)and octahedral Co^(3+)(CoOh),is considered as promising earth-abundant electrocatalyst for chlorine evolution reaction(CER).Identifying the catalytic contribution of geometric Co site in the electrocatalytic CER plays a pivotal role to precisely modulate electronic configuration of active Co sites to boost CER.Herein,combining density functional theory calculations and experiment results assisted with operando analysis,we found that the Co_(Oh) site acts as the main active site for CER in spinel Co_(3)O_(4),which shows better Cl^(-)adsorption and more moderate intermediate adsorption toward CER than CoTd site,and does not undergo redox transition under CER condition at applied potentials.Guided by above findings,the oxygen vacancies were further introduced into the Co_(3)O_(4) to precisely manipulate the electronic configuration of Co_(Oh) to boost Cl^(-)adsorption and optimize the reaction path of CER and thus to enhance the intrinsic CER activity significantly.Our work figures out the importance of geometric configuration dependent CER activity,shedding light on the rational design of advanced electrocatalysts from geometric configuration optimization at the atomic level. 展开更多
关键词 Chlorine evolution reaction Geometry effects Active chlorine Electronic configuration optimization Spinel oxides
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Practical operating flexibility of a bifunctional freestanding membrane for efficient anion exchange membrane water electrolysis across all current ranges
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作者 Hong-Jin Son Jeemin Hwang +4 位作者 Min Young Choi Seung Hee Park Jae Hyuk Jang Byungchan Han Sung Hoon Ahn 《Carbon Energy》 SCIE EI CAS CSCD 2024年第9期306-324,共19页
This study explores a symmetric configuration approach in anion exchange membrane(AEM)water electrolysis,focusing on overcoming adaptability challenges in dynamic conditions.Here,a rapid and mild synthesis technique f... This study explores a symmetric configuration approach in anion exchange membrane(AEM)water electrolysis,focusing on overcoming adaptability challenges in dynamic conditions.Here,a rapid and mild synthesis technique for fabricating fibrous membrane-type catalyst electrodes is developed.Our method leverages the contrasting oxidation states between the sulfur-doped NiFe(OH)2 shell and the metallic Ni core,as revealed by electron energy loss spectroscopy.Theoretical evaluations confirm that the S–NiFe(OH)_(2) active sites optimize free energy for alkaline water electrolysis intermediates.This technique bypasses traditional energy-intensive processes,achieving superior bifunctional activity beyond current benchmarks.The symmetric AEM water electrolyzer demonstrates a current density of 2 A cm^(-2) at 1.78 V at 60℃ in 1 M KOH electrolyte and also sustains ampere-scale water electrolysis below 2.0 V for 140 h even in ambient conditions.These results highlight the system's operational flexibility and structural stability,marking a significant advance-ment in AEM water electrolysis technology. 展开更多
关键词 AEM water electrolysis fibrous membrane iR correction free operational stability symmetric configuration
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Measurement of 2p-3d absorption in a hot molybdenum plasma
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作者 Gang Xiong Bo Qing +17 位作者 Zhiyu Zhang Longfei Jing Yang Zhao Minxi Wei Yimeng Yang Lifei Hou Chengwu Huang Tuo Zhu Tianming Song Min Lv Yan Zhao Yuxue Zhang Guohong Yang Zeqing Wu Jun Yan Yaming Zou Jiyan Zhang Jiamin Yang 《Matter and Radiation at Extremes》 SCIE EI CSCD 2024年第4期68-79,共12页
We present measurements of the 2p-3d transition opacity of a hot molybdenum-scandium sample with nearly half-vacant molybdenum M-shell configurations.A plastic-tamped molybdenum-scandium foil sample is radiatively hea... We present measurements of the 2p-3d transition opacity of a hot molybdenum-scandium sample with nearly half-vacant molybdenum M-shell configurations.A plastic-tamped molybdenum-scandium foil sample is radiatively heated to high temperature in a compact D-shaped gold Hohlraum driven by∼30 kJ laser energy at the SG-100 kJ laser facility.X rays transmitted through the molybdenum and scandium plasmas are diffracted by crystals and finally recorded by image plates.The electron temperatures in the sample in particular spatial and temporal zones are determined by the K-shell absorption of the scandium plasma.A combination of the IRAD3D view factor code and the MULTI hydrodynamic code is used to simulate the spatial distribution and temporal behavior of the sample temperature and density.The inferred temperature in the molybdenum plasma reaches a average of 138±11 eV.A detailed configuration-accounting calculation of the n=2–3 transition absorption of the molybdenum plasma is compared with experimental measurements and quite good agreement is found.The present measurements provide an opportunity to test opacity models for complicated M-shell configurations. 展开更多
关键词 MOLYBDENUM ABSORPTION CONFIGURATION
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Network Configuration Entity Extraction Method Based on Transformer with Multi-Head Attention Mechanism
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作者 Yang Yang Zhenying Qu +2 位作者 Zefan Yan Zhipeng Gao Ti Wang 《Computers, Materials & Continua》 SCIE EI 2024年第1期735-757,共23页
Nowadays,ensuring thequality of networkserviceshas become increasingly vital.Experts are turning toknowledge graph technology,with a significant emphasis on entity extraction in the identification of device configurat... Nowadays,ensuring thequality of networkserviceshas become increasingly vital.Experts are turning toknowledge graph technology,with a significant emphasis on entity extraction in the identification of device configurations.This research paper presents a novel entity extraction method that leverages a combination of active learning and attention mechanisms.Initially,an improved active learning approach is employed to select the most valuable unlabeled samples,which are subsequently submitted for expert labeling.This approach successfully addresses the problems of isolated points and sample redundancy within the network configuration sample set.Then the labeled samples are utilized to train the model for network configuration entity extraction.Furthermore,the multi-head self-attention of the transformer model is enhanced by introducing the Adaptive Weighting method based on the Laplace mixture distribution.This enhancement enables the transformer model to dynamically adapt its focus to words in various positions,displaying exceptional adaptability to abnormal data and further elevating the accuracy of the proposed model.Through comparisons with Random Sampling(RANDOM),Maximum Normalized Log-Probability(MNLP),Least Confidence(LC),Token Entrop(TE),and Entropy Query by Bagging(EQB),the proposed method,Entropy Query by Bagging and Maximum Influence Active Learning(EQBMIAL),achieves comparable performance with only 40% of the samples on both datasets,while other algorithms require 50% of the samples.Furthermore,the entity extraction algorithm with the Adaptive Weighted Multi-head Attention mechanism(AW-MHA)is compared with BILSTM-CRF,Mutil_Attention-Bilstm-Crf,Deep_Neural_Model_NER and BERT_Transformer,achieving precision rates of 75.98% and 98.32% on the two datasets,respectively.Statistical tests demonstrate the statistical significance and effectiveness of the proposed algorithms in this paper. 展开更多
关键词 Entity extraction network configuration knowledge graph active learning TRANSFORMER
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Formation of large-and medium-sized Cretaceous volcanic reservoirs in the offshore Bohai Bay Basin,East China
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作者 XU Changgui ZHANG Gongcheng +3 位作者 HUANG Shengbing SHAN Xuanlong LIU Tingyu LI Jiahui 《Petroleum Exploration and Development》 SCIE 2024年第3期535-547,共13页
Based on the geological and geophysical data of Mesozoic oil-gas exploration in the sea area of Bohai Bay Basin and the discovered high-yield volcanic oil and gas wells since 2019,this paper methodically summarizes th... Based on the geological and geophysical data of Mesozoic oil-gas exploration in the sea area of Bohai Bay Basin and the discovered high-yield volcanic oil and gas wells since 2019,this paper methodically summarizes the formation conditions of large-and medium-sized Cretaceous volcanic oil and gas reservoirs in the Bohai Sea.Research shows that the Mesozoic large intermediate-felsic lava and intermediate-felsic composite volcanic edifices in the Bohai Sea are the material basis for the formation of large-scale volcanic reservoirs.The upper subfacies of effusive facies and cryptoexplosive breccia subfacies of volcanic conduit facies of volcanic vent-proximal facies belts are favorable for large-scale volcanic reservoir formation.Two types of efficient reservoirs,characterized by high porosity and medium to low permeability,as well as medium porosity and medium to low permeability,are the core of the formation of large-and medium-sized volcanic reservoirs.The reservoir with high porosity and medium to low permeability is formed by intermediate-felsic vesicular lava or the cryptoexplosive breccia superimposed by intensive dissolution.The reservoir with medium porosity and medium to low permeability is formed by intense tectonism superimposed by fluid dissolution.Weathering and tectonic transformation are main formation mechanisms for large and medium-sized volcanic reservoirs in the study area.The low-source“source-reservoir draping type”is the optimum source-reservoir configuration relationship for large-and medium-sized volcanic reservoirs.There exists favorable volcanic facies,efficient reservoirs and source-reservoir draping configuration relationship on the periphery of Bozhong Sag,and the large intermediate-felsic lava and intermediate-felsic composite volcanic edifices close to strike-slip faults and their branch faults are the main directions of future exploration. 展开更多
关键词 Bohai Sea CRETACEOUS large-and medium-sized volcanic reservoirs effective reservoir source-reservoir configuration exploration direction
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Review of the Configuration and Transient Stability of Large-scale Renewable Energy Generation through Hybrid DC Transmission
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作者 Xinshou Tian Yongning Chi +1 位作者 Longxue Li Hongzhi Liu 《CES Transactions on Electrical Machines and Systems》 EI CSCD 2024年第2期115-126,共12页
Based on the complementary advantages of Line Commutated Converter(LCC)and Modular Multilevel Converter(MMC)in power grid applications,there are two types of hybrid DC system topologies:one is the parallel connection ... Based on the complementary advantages of Line Commutated Converter(LCC)and Modular Multilevel Converter(MMC)in power grid applications,there are two types of hybrid DC system topologies:one is the parallel connection of LCC converter stations and MMC converter stations,and the other is the series connection of LCC and MMC converter stations within a single station.The hybrid DC transmission system faces broad application prospects and development potential in large-scale clean energy integration across regions and the construction of a new power system dominated by new energy sources in China.This paper first analyzes the system forms and topological characteristics of hybrid DC transmission,introducing the forms and topological characteristics of converter-level hybrid DC transmission systems and system-level hybrid DC transmission systems.Next,it analyzes the operating characteristics of LCC and MMC inverter-level hybrid DC transmission systems,provides insights into the transient stability of hybrid DC transmission systems,and typical fault ride-through control strategies.Finally,it summarizes the networking characteristics of the LCC-MMC series within the converter station hybrid DC transmission system,studies the transient characteristics and fault ridethrough control strategies under different fault types for the LCC-MMC series in the receiving-end converter station,and investigates the transient characteristics and fault ride-through control strategies under different fault types for the LCC-MMC series in the sending-end converter station. 展开更多
关键词 Hybrid DC transmission Transient stability CONFIGURATION Control system
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Solution for Output Coordination Equations of Several Typical Parallel Six-Dimensional Acceleration Sensing Mechanisms
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作者 ZHANG Xianzhu YOU Jingjing ZHANG Yuanwei 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2024年第S01期96-102,共7页
Aiming at the problem that it is difficult to generate the dynamic decoupling equation of the parallel six-dimensional acceleration sensing mechanism,two typical parallel six-dimensional acceleration sensing mechanism... Aiming at the problem that it is difficult to generate the dynamic decoupling equation of the parallel six-dimensional acceleration sensing mechanism,two typical parallel six-dimensional acceleration sensing mechanisms are taken as examples.By analyzing the scale constraint relationship between the hinge points on the mass block and the hinge points on the base of the sensing mechanism,a new method for establishing the dynamic equation of the sensing mechanism is proposed.Firstly,based on the scale constraint relationship between the hinge points on the mass block and the hinge points on the base of the sensing mechanism,the expression of the branch rod length is obtained.The inherent constraint relationship between the branches is excavated and the branch coordination closed chain of the“12-6”configuration is constructed.The output coordination equation of the sensing mechanism is successfully derived.Secondly,the dynamic equations of“12-4”and“12-6”configurations are constructed by the Newton-Euler method,and the forward decoupling equations of the two configurations are solved by combining the dynamic equations and the output coordination equations.Finally,the virtual prototype experiment is carried out,and the maximum reference errors of the forward decoupling equations of the two configuration sensing mechanisms are 4.23%and 6.53%,respectively.The results show that the proposed method is effective and feasible,and meets the real-time requirements. 展开更多
关键词 six-dimensional acceleration sensor parallel mechanism topological configuration coordination equation dynamics
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A numerical survey of parameters to reach ignition condition for axial compression of a large-sized field reversed configuration
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作者 李宜霖 廖晖 +1 位作者 周海洋 孙玄 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第5期47-55,共9页
Field reversed configuration(FRC)is widely considered as an ideal target plasma for magnetoinertial fusion.However,its confinement and stability,both proportional to the radius,will deteriorate inevitably during radia... Field reversed configuration(FRC)is widely considered as an ideal target plasma for magnetoinertial fusion.However,its confinement and stability,both proportional to the radius,will deteriorate inevitably during radial compression.Hence,we propose a new fusion approach based on axial compression of a large-sized FRC.The axial compression can be made by plasma jets or plasmoids converging onto the axial ends of the FRC.The parameter space that can reach the ignition condition while preserving the FRC's overall quality is studied using a numerical model based on different FRC confinement scalings.It is found that ignition is possible for a large FRC that can be achieved with the current FRC formation techniques if compression ratio is greater than 50.A more realistic compression is to combine axial with moderate radial compression,which is also presented and calculated in this work. 展开更多
关键词 field reversed configuration magnetized target fusion axial compression
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Tuning Structural and Electronic Configuration of FeN_(4) via External S for Enhanced Oxygen Reduction Reaction
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作者 Shidong Li Lixue Xia +9 位作者 Jiantao Li Zhuo Chen Wei Zhang Jiexin Zhu Ruohan Yu Fang Liu Sungsik Lee Yan Zhao Liang Zhou Liqiang Mai 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第2期93-101,共9页
The Fe-N-C material represents an attractive oxygen reduction reaction electrocatalyst,and the FeN_(4)moiety has been identified as a very competitive catalytic active site.Fine tuning of the coordination structure of... The Fe-N-C material represents an attractive oxygen reduction reaction electrocatalyst,and the FeN_(4)moiety has been identified as a very competitive catalytic active site.Fine tuning of the coordination structure of FeN_(4)has an essential impact on the catalytic performance.Herein,we construct a sulfur-modified Fe-N-C catalyst with controllable local coordination environment,where the Fe is coordinated with four in-plane N and an axial external S.The external S atom affects not only the electron distribution but also the spin state of Fe in the FeN_(4)active site.The appearance of higher valence states and spin states for Fe demonstrates the increase in unpaired electrons.With the above characteristics,the adsorption and desorption of the reactants at FeN_(4)active sites are optimized,thus promoting the oxygen reduction reaction activity.This work explores the key point in electronic configuration and coordination environment tuning of FeN_(4)through S doping and provides new insight into the construction of M-N-C-based oxygen reduction reaction catalysts. 展开更多
关键词 coordination structure electronic configuration FeN_(4)moiety oxygen reduction reaction sulfur doping
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Effect of the Particle Packing Configuration on Fixed Bed Performance
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作者 Li Ziqi Bao Di +1 位作者 Zhou Han Tang Xiaojin 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第1期152-160,共9页
Fixed-bed reactors are generally considered the optimal choice for numerous multi-phase catalytic reactions due to their excellent performance and stability.However,conventional fixed beds often encounter challenges r... Fixed-bed reactors are generally considered the optimal choice for numerous multi-phase catalytic reactions due to their excellent performance and stability.However,conventional fixed beds often encounter challenges related to inadequate mass transfer and a high pressure drop caused by the non-uniform void fraction distribution.To enhance the overall performance of fixed beds,the impact of different packing configurations on performance was investigated.Experimental and simulation methods were used to investigate the fluid flow and mass transfer performances of various packed beds under different flow rates.It was found that structured beds exhibited a significantly lower pressure drop per unit length than conventional packed beds.Furthermore,the packing configurations had a critical role in improving the overall performance of fixed beds.Specifically,structured packed beds,particularly the H-2 packing configuration,effectively reduced the pressure drop per unit length and improved the mass transfer efficiency.The H-2 packing configuration consisted of two parallel strips of particles in each layer,with strips arranged perpendicularly between adjacent layers,and the spacing between the strips varied from layer to layer. 展开更多
关键词 packing configurations fixed bed Computational Fluid Dynamics simulation pressure drop mass transfer
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