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Coupling of methanol and long chain alkanes on molecular sieves with CHA structures
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作者 YANG Chuang WANG Kangjun +1 位作者 LI Jinzhe LIU Zhongmin 《燃料化学学报(中英文)》 北大核心 2026年第2期64-75,共12页
The coupling reactions of methanol and long-chain alkanes(n-dodecane,n-tetradecane and n-hexadecane)over CHA-type molecular sieves were studied in a fixed bed reactor.Over SAPO-34 and SSZ-13,it was found that the indu... The coupling reactions of methanol and long-chain alkanes(n-dodecane,n-tetradecane and n-hexadecane)over CHA-type molecular sieves were studied in a fixed bed reactor.Over SAPO-34 and SSZ-13,it was found that the induction period of methanol conversion was shortened by the introduction of long-chain alkanes.However,the addition of long-chain alkanes had little influence on the product distribution.Polymethylbenzenes and the derivatives were the main retained species on spent SSZ-13 catalyst,while adamantanes were the main retained species on SAPO-34.This indicates that coking species formation was mainly related to the further transformation of long-chain alkane/methanol coupling products at acid sites of the molecular sieve.These findings provide valuable information of long chain alkanes conversion and methanol reaction behavior of induction period over small pore CHA molecular sieves. 展开更多
关键词 METHANOL long-chain alkane coupling transformation induction period molecular sieves
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Numerical Simulation on Thermomechanical Coupling Process in Friction Stir-Assisted Wire Arc Additive Manufacturing
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作者 Li Long Xiao Yichen +2 位作者 Shi Lei Chen Ji Wu Chuansong 《稀有金属材料与工程》 北大核心 2026年第1期1-8,共8页
Wire arc additive manufacturing(WAAM)has emerged as a promising approach for fabricating large-scale components.However,conventional WAAM still faces challenges in optimizing microstructural evolution,minimizing addit... Wire arc additive manufacturing(WAAM)has emerged as a promising approach for fabricating large-scale components.However,conventional WAAM still faces challenges in optimizing microstructural evolution,minimizing additive-induced defects,and alleviating residual stress and deformation,all of which are critical for enhancing the mechanical performance of the manufactured parts.Integrating interlayer friction stir processing(FSP)into WAAM significantly enhances the quality of deposited materials.However,numerical simulation research focusing on elucidating the associated thermomechanical coupling mechanisms remains insufficient.A comprehensive numerical model was developed to simulate the thermomechanical coupling behavior in friction stir-assisted WAAM.The influence of post-deposition FSP on the coupled thermomechanical response of the WAAM process was analyzed quantitatively.Moreover,the residual stress distribution and deformation behavior under both single-layer and multilayer deposition conditions were investigated.Thermal analysis of different deposition layers in WAAM and friction stir-assisted WAAM was conducted.Results show that subsequent layer deposition induces partial remelting of the previously solidified layer,whereas FSP does not cause such remelting.Furthermore,thermal stress and deformation analysis confirm that interlayer FSP effectively mitigates residual stresses and distortion in WAAM components,thereby improving their structural integrity and mechanical properties. 展开更多
关键词 friction stir processing wire arc additive manufacturing numerical simulation thermomechanical coupling temperature field DEFORMATION
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Coupling Development Between Digital Economy–Agriculture Integration and Rural Revitalization in China:Spatiotemporal Disparities and Evolution Trends
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作者 Peng Xiangjun Jia Qingsong 《Contemporary Social Sciences》 2026年第1期71-89,共19页
This study aims to promote the optimization and upgrading of the economic structure in rural areas of China by focusing on the coupling coordination mechanism between digital economy–agriculture integration and rural... This study aims to promote the optimization and upgrading of the economic structure in rural areas of China by focusing on the coupling coordination mechanism between digital economy–agriculture integration and rural revitalization.By examining panel data from 30 Chinese provinces,autonomous regions,and municipalities between 2011 and 2022,the research constructs a weight-based evaluation system that integrates subjective and objective methods and a coupling coordination model to reveal its dynamic evolution patterns.Key findings indicate that digital economy–agriculture integration and rural revitalization achieve cross-coupling through critical activities.The impact of digital-agriculture integration on advancing rural revitalization lags by 2–3 years.Although the coupling development degree between the two systems continues to improve,it remains at the stage of primary coordination.Regional disparities are significant,showing a gradient pattern of“high degree of coupling development in the east and low degree of coupling development in the west.” 展开更多
关键词 digital economy-agriculture integration rural revitalization coupling coordination coupling development
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A mesoscale stress-damage-seepage coupling model of hydraulic asphalt concrete incorporating the damage-dependent permeability coefficient of asphalt mortar
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作者 Nanxuan Qian Wei Luo +3 位作者 Bingyu Mei Desheng Yin Yixin Feng Hui Peng 《Acta Mechanica Sinica》 2026年第1期192-208,共17页
Hydraulic asphalt concrete(HAC)has been increasingly employed as an appropriate impervious structure in hydraulic and hydropower engineering.However,asphalt mortar,usually seen as the matrix of HAC composite,is partic... Hydraulic asphalt concrete(HAC)has been increasingly employed as an appropriate impervious structure in hydraulic and hydropower engineering.However,asphalt mortar,usually seen as the matrix of HAC composite,is particularly prone to damage under combined stress and seepage interactions,and the mesoscale investigations on the damage-seepage coupling behavior of HAC under complex stress states remain limited.This research develops a numerical three-dimensional mesoscale model composed of asphalt mortar and polyhedral aggregate to investigate the stress-damage-seepage coupling behavior in HAC.In this model,asphalt mortar yields the viscoelastic continuum damage law and aggregate obeys the Mazars’elastic-brittle damage law;simultaneously,the effective permeability coefficient of asphalt mortar is assumed to follow an exponential function of damage.The predicted deviatoric stress-strain and hydraulic gradient-seepage curves both are in good agreement with the reported experimental results,which shows the proposed model is valid and reasonable.The simulated results indicate that the damaged asphalt mortar can induce localized areas of high permeability,which in turn affects the overall impervious performance of HAC. 展开更多
关键词 Effective permeability coefficient Viscoelastic continuum damage Stress-seepage coupling
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Shear fracturing behavior and mechanism of intact granite under thermal-mechanical coupling loading
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作者 Fanzhen Meng Zhengyang Xu +5 位作者 Jianhua Han Qijin Cai Yuantao Wen Zaiquan Wang Yuzong Li Jingjing Lu 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1429-1446,共18页
High rock temperature is a great challenge frequently encountered during subsurface resource recovery and deep underground space utilization,and it is still unclear how the granitic rock responds to realtime high temp... High rock temperature is a great challenge frequently encountered during subsurface resource recovery and deep underground space utilization,and it is still unclear how the granitic rock responds to realtime high temperature upon shear loading.To better understand the shear fracture behavior and underlying processes of intact granite exposed to thermal-mechanical coupling loading,direct shear tests were conducted utilizing a newly built testing apparatus at varied normal stresses and high temperatures.Influencesof different temperatures and different heating methods(real-time heating and thermal treatment)on the shear mechanical behavior were compared and discussed.Results indicate that shear stress fluctuationswith some small stress drops occur as shear stress is approaching the peak strength under real-time heating,accompanied by more and earlier AE signal uprushes.This suggests that greater cracking events occur earlier during real-time heating than after thermal treatment,resulting in a lower peak shear strength.Furthermore,the peak shear strength,post-peak stress drop,and cohesion rise from room temperature(RT)to 200℃(the peak strength increases by 8%,5.8%,and 9.9%under normal stress of 5 MPa,15 MPa,and 20 MPa,correspondingly),and subsequently decline from 200℃to 400℃.Temperature has a limited impact on shear stiffness from RT to 200℃,but significantlyreduces it from 200℃to 400℃,with drops of 15%,7.9%,and 10%under normal stress of 5 MPa,15 MPa,and 20 MPa,respectively.Moreover,the shear strength and stiffness under real-time heating are lower than those for the thermally treated specimens.The strengthening of intact granite below 200℃upon shear is associated with loss of water and a more compacted structure,while the weakening effect of temperature on shear strength from 200℃to 400℃is due to the new thermal cracks and less brittle and stiff of minerals. 展开更多
关键词 Thermal-mechanical coupling Direct shear test Thermal cracks Granite shear failure
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Thermomechanical coupling analysis of granite fracture shear behavior:True triaxial test and numerical approaches
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作者 Zhufeng Yue Fanzhen Meng +4 位作者 Qijin Cai Dongliang Tian Yuantao Wen Wei Wang Dawei Hu 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1337-1358,共22页
High geo-stress and high temperature in deep rock engineering increase the possibility of engineering and geological disasters in discontinuous rocks.However,the influence of thermomechanical coupling on the shear beh... High geo-stress and high temperature in deep rock engineering increase the possibility of engineering and geological disasters in discontinuous rocks.However,the influence of thermomechanical coupling on the shear behavior and damage evolution of prefractured granite remains immature.In this context,true triaxial laboratory tests and discrete element method simulations under different confining pressures(σ3=3 MPa,σ2=4 MPa,andσ3=80 MPa,σ2=100 MPa)and temperatures(25℃-500℃)were carried out on rough granite fractures with two different orientations.Results indicate that high temperature and high confining pressure increase the peak strength of the prefractured specimen,leading to more microcracks in the host rock and more gouges between the surfaces.Thermal strengthening at low temperatures(<300℃)and residual stick-slip only occur under a greater confining pressure for prefractured specimens.High confining pressure suppresses generation of the thermal microcracks in the heating stage.Cracks first initiate in the asperities on the fracture surfaces,and then propagate into the rock matrix during the mechanical loading stage.In addition,prefractured granite with a larger fracture angle is characterized by smaller peak and residual strength,faster residual slip,fewer new cracks on the specimen surface,and a more pronounced thermal strengthening effect on peak strength.The slip tendency analysis indicates that a higher maximum principal stress(s1)and a large fracture angle(45°-75°)generally result in a higher potential for fracture slip or activation.This study will contribute to a better understanding of the fracture shear mechanism under true triaxial thermomechanical coupling conditions and provides new insights into the stability evaluation of deep dynamic geological hazards. 展开更多
关键词 Thermomechanical coupling effect Real-time high temperature Prefractured granite Fracture angle True triaxial shear test
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Asymmetric coupling of atop-type and hollow-type adsorbed ^(*)CO to boost electrocatalytic CO_(2)-to-C_(2) conversion on high-index Cu_(2)O crystal planes
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作者 Wei Peng Yao Shen +6 位作者 Xiaolin Yu Chenghang Zheng Xiao Zhang Jingkai Zhao Jiexu Ye Shihan Zhang Xiang Gao 《Chinese Chemical Letters》 2026年第1期577-583,共7页
Cuprous oxide(Cu_(2)O) is one of the most promising catalysts for electrochemical conversion of CO_(2) into value-added C_(2) products.The efficiency of CO_(2)-to-C_(2) conversion is highly dependent on the Cu_(2)O cr... Cuprous oxide(Cu_(2)O) is one of the most promising catalysts for electrochemical conversion of CO_(2) into value-added C_(2) products.The efficiency of CO_(2)-to-C_(2) conversion is highly dependent on the Cu_(2)O crystal plane orientation and the corresponding adsorbed ^(*)CO species.Herein,we constructed high-index crystal planes(311) in Cu_(2)O(CO-Cu_(2)O) via a facile self-selective CO-induced strategy under a CO atmosphere,which was verified by high-resolution transmission electron microscopy(HR-TEM) and atomic force microscopy(AFM) results.By exploiting the high surface energy of the high index crystal planes,^(*)CO species are stabilized in CO-Cu_(2)O during CO_(2)RR,resulting in exceptional catalytic performance for CO_(2)-to-C_(2)products.In situ infrared spectroscopy revealed that both atop-type(^(*)CO_(atop)) and hollow-type(^(*)CO_(hollow)) adsorption of ^(*)CO species occurred on the CO-Cu_(2)O.The asymmetric C-C coupling energy barrier between ^(*)CO_(atop) and ^(*)CO_(hollow) in(311) crystal plane decreases by 47.8 % compared to the symmetric coupling of ^(*)CO_(atop) in conventional(100) crystal planes.Consequently,the Faradaic efficiency of C_(2) products generated with CO-Cu_(2)O was increased by as high as 100 % compared to that with pristine Cu_(2)O. 展开更多
关键词 Electrocatalytic conversion Adsorbed^(*)CO Asymmetric C-C coupling Self-selective CO-induced strategy Cu_(2)O-based catalysts
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Planning model for electro–hydrogen coupling systems for multistage emission reduction and carbon–green-certificate markets
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作者 Jingbo Zhao Zhengping Gao +3 位作者 Tianhui Zhao Cheng Huang Zhe Chen Dajiang Wang 《Global Energy Interconnection》 2026年第1期68-82,共15页
Hydrogen,as a zero-carbon secondary energy carrier,provides a unified pathway for low-carbon energy transformation.In electro–hydrogen coupling systems(EHCSs),surplus renewable power is stored via water electrolysis ... Hydrogen,as a zero-carbon secondary energy carrier,provides a unified pathway for low-carbon energy transformation.In electro–hydrogen coupling systems(EHCSs),surplus renewable power is stored via water electrolysis and later reconverted to electricity using fuel cells or gas turbines,enhancing the system’s flexibility and reliability in support of deep decarbonization.This study constructs an electricity–hydrogen energy-recycling model based on a coupling relationship considering the bidirectional conversion between electricity and hydrogen.A multistage carbon-emission-reduction indicator constraint is also established.Additionally,the green-certificate and carbon trading markets are introduced to optimize equipment investment and operation costs while achieving carbon-emission reduction.A case study reveals that the proposed EHCS planning model effectively allocates carbon emissions across different system stages,while mitigating economic repercussions,thus ensuring closer alignment with China’s emission-reduction policies.Incorporating diverse market mechanisms significantly enhances the system’s economy and decision-making flexibility,particularly in addressing future challenges in the energy market. 展开更多
关键词 Hydrogen energy Environmental impact Electro-hydrogen coupling systems Multimarket and multistage emission reduction Dual carbon goals
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A two-point three-phase resolved coupling framework for modeling boulder-laden debris flows
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作者 Yangfan Ma Mitsuteru Asai +3 位作者 Bin Su Zheng Han Changze Li Guangqi Chen 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期932-953,共22页
Stony debris flows,characterized by coarse boulders embedded in a sediment-laden matrix,greatly amplify destructive potential by altering flow dynamics and impact forces.Conventional single-phase particle-fluidmixture... Stony debris flows,characterized by coarse boulders embedded in a sediment-laden matrix,greatly amplify destructive potential by altering flow dynamics and impact forces.Conventional single-phase particle-fluidmixture models often struggle to capture the complexities introduced by coarse boulders and multi-phase interactions,while strong-coupling methods can be computationally prohibitive for practical hazard assessments.In this study,we propose a semi-hybrid,fully resolved coupling numerical framework for modeling boulder-laden debris flows.This framework conceptualizes debris flows as a composite system comprising a continuous viscous fluidphase(including finesediments)and a discrete phase of arbitrarily shaped coarse particles.The continuous phase is treated as a generalized nonlinear Coulomb-viscoplastic fluidusing the smoothed particle hydrodynamics(SPH)method,while coarse particles are modeled via the distributed contact discrete element method(DCDEM).These two phases are coupled through an efficienttwo-way resolved scheme,ensuring accurate simulation of flow-boulder interactions within a unifiedtimeframe.We validate the proposed method against two physical experiments:(1)gravity-driven concrete flows and(2)debris flowinteracting with slit-type barriers.Results confirmthe method's robustness in accurately capturing fluid-solid-structureinteractions and deposition processes.Its capabilities are further showcased through the simulation of a stony debris-flowevent inWenchuan County,China,highlighting its promise for real-world engineering applications and validating the effectiveness of the existing cascade dam system in mitigating debrisflowimpact and energy dissipation. 展开更多
关键词 Debris flow Large boulders Smooth particle hydrodynamics(SPH) Discrete element method(DEM) Multi-phase Resolved coupling
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Paired electrochemical N−N coupling:Potential-mediated selective electrosynthesis of azoxy aromatics plus 5,5′-azotetrazolate energetic materials in aqueous media
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作者 Dengke Xiong Xiaoyang He +5 位作者 Xuan Liu Zhentao Tu Shujie Xue Jianying Wang Deli Wu Zuofeng Chen 《Journal of Energy Chemistry》 2025年第8期861-871,共11页
Azoxy aromatics are extensively utilized in materials science,pharmaceuticals,and synthetic chemistry,but their controlled and environmentally-friendly synthesis has rarely been reported.Herein,a potential-mediated el... Azoxy aromatics are extensively utilized in materials science,pharmaceuticals,and synthetic chemistry,but their controlled and environmentally-friendly synthesis has rarely been reported.Herein,a potential-mediated electrosynthesis strategy was developed by selective reduction of 4-nitrobenzyl alcohol(4-NBA)on Mn-doped Ni_(2)P nanosheets@nickel foam(Mn-Ni_(2)P/NF),enabling efficient N−N coupling to produce Azoxy with 100%selectivity at potentials of−0.6 to−0.8 V(vs.Hg/HgO).At more cathodic potentials,the product was converted to Azo and then to amino aromatics due to facilitated nitrogen hydrogenation.Additionally,the organic energetic material,5,5′-azotetrazolate,was also synthesized by anodic N−N coupling of 5-amino-1H-tetrazole on Cu(OH)_(2)nanowires@copper foam(Cu(OH)_(2)/CF).It bypassed harsh conditions(strong oxidants,high temperature,by-products separation,etc.)for the traditional synthesis of this class of materials.As a consequence,a two-electrode electrolyzer Cu(OH)_(2)/CF||Mn-Ni_(2)P/NF was assembled,allowing paired electrochemical N−N coupling into Azoxy and 5,5′-azotetrazolate.It achieves a current density of 50 mA cm^(−2)at a voltage of only 1.19 V,880 mV lower than the competitive water splitting.This electrolyzer can be efficiently driven by a 1.2 V solar panel with excellent yield and selectivity,paving the way for green synthesis of valuable chemicals through electrochemical N−N coupling strategies. 展开更多
关键词 azoxy azo Amino aromatics Potential-mediated electrosynthesis Metal phosphides N-N coupling
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Coupling dynamics of SDGs in Tajikistan from 2001 to 2023
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作者 Ranna HAZIHAN DU Hongru +2 位作者 HE Chuanchuan Kobiljon Khushvakht KHUSHVAKHTZODA Bobozoda KOMIL 《Regional Sustainability》 2026年第1期54-74,共21页
Since the United Nations launched the Sustainable Development Goals(SDGs)in 2015,global implementation has steadily advanced,yet prominent challenges persist.Progress has been uneven across regions and countries,with ... Since the United Nations launched the Sustainable Development Goals(SDGs)in 2015,global implementation has steadily advanced,yet prominent challenges persist.Progress has been uneven across regions and countries,with Tajikistan representing a typical example of such disparities.Based on 81 SDG indicators for Tajikistan from 2001 to 2023,this study applied a three-level coupling network framework:at the microscale,it identified synergies and trade-offs between indicators;at the mesoscale,it examined the strength and direction of linkages within four SDG-related components(society,finance,governance,and environment);and at the global level,it focused on the overall SDG interlinkages.Spearman’s rank correlation,sliding window method,and topological properties were employed to analyze the coupling dynamics of SDGs.Results showed that over 70.00%of associations in the global SDG network were of medium-to-low intensity,alongside extremely strong ones(|r|value approached 1.00,where r is the correlation coefficient).SDG interactions were generally limited,with stable local synergy clusters in core livelihood sectors.Network modularity fluctuated,reflecting a cycle of differentiation,integration,and fragmentation,while coupling efficiency varied with the external environment.Each component exhibited distinct functional characteristics.The social component maintained high connectivity through the“poverty alleviation-education-healthcare”loop.The environmental component shifted toward coordinated eco-economic governance.The governance-related component broke interdepartmental barriers,while the financial component showed weak links between resource-based indicators and consumption/employment indicators.Tajikistan’s SDG coupling evolved through three phases:survival-oriented(2001–2012),policy integration(2013–2018),and shock adaptation(2019–2023).These phases were driven by policy changes,resource industries,governance optimization,and external factors.This study enriches the analytical framework for understanding the dynamic coupling of SDGs in mountainous resource-dependent countries and provides empirical evidence to support similar countries in formulating phase-specific SDG promotion strategies. 展开更多
关键词 SUSTAINABLE DEVELOPMENT Goals(SDGs) Climate change coupling network analysis Spearman’s rank correlation Synergic relationships Trade-off relationships TAJIKISTAN
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Thermo-hydro-mechanical coupling analysis of dynamic responses of green sandstone subjected to high-strain rates:Experimental study and damage-based modeling
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作者 Shi Liu Zewei Chen 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第1期542-565,共24页
Deep rock engineering is affected by coupled thermo-hydro-mechanical(THM)-dynamic fields,necessitating the elucidation of the dynamic mechanical behavior and failure mechanisms.This study utilized a Multi-field Couple... Deep rock engineering is affected by coupled thermo-hydro-mechanical(THM)-dynamic fields,necessitating the elucidation of the dynamic mechanical behavior and failure mechanisms.This study utilized a Multi-field Coupled Controlled Split Hopkinson Pressure Bar(MCC-SHPB)system to elucidate the cross-scale dynamic responses of rocks and the boundaries of failure modes under THM coupling.Impact tests were conducted on green sandstone under coupled conditions of temperature(25℃-80℃),confining pressure(0-15 MPa),and seepage water pressure(0-15 MPa).Scanning electron microscopy(SEM)microstructural characterization and COMSOL Multiphysics numerical simulations were conducted,and a dynamic constitutive theoretical framework and failure-prediction methodology were established.We investigated the impact toughness index(I_(t)),dynamic modulus(E_(d)),dynamic triaxial compressive strength(TCS_(d)),fragmentation degree(W),and failure modes of green sandstone under thermo-confining pressure-seepage-impact loading conditions.The key findings reveal that the(I_(t))reflects different energy regulation mechanisms across different confining pressure regimes.Thermal-microcrack interactions dominate at low pressure,and energy absorption prevails at high pressure.A triphasic dynamic modulus model captures stiffness evolution under energy-driven conditions,revealing cross-scale crack nucleation-propagation and fragment reorganization.The TCSd inflection point signifies energy dissipation shifts,causing nonlinear skeleton bearing-capacity degradation.A critical criterion based on the W was established to distinguish between the two failure modes and predict the unstable failure initiation.Numerical simulations were used to elucidate the effects of inertia-dominated crack propagation and stress wave interference,validating the critical criterion and the predictive accuracy of the theoretical model during cross-scale failure.This study provides a theoretical foundation for assessing the dynamic stability of rock masses subjected to multi-field coupling during deep resource exploitation. 展开更多
关键词 Multi-field coupled controlled split Hopkinson pressure bar(MCC-SHPB) Impact toughness index Modulus evolution model Fragmentation degree Thermo-hydro-mechanical failure criterion
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Steady‑state microbunching based on transverse‑longitudinal coupling
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作者 Xiu‑Jie Deng Alexander Wu Chao +3 位作者 Wen‑Hui Huang Zi‑Zheng Li Zhi‑Long Pan Chuan‑Xiang Tang 《Nuclear Science and Techniques》 2026年第1期1-49,共49页
In this study,three specific scenarios of a novel accelerator light source mechanism called steady-state microbunching(SSMB)were studied:longitudinal weak focusing,longitudinal strong focusing,and generalized longitud... In this study,three specific scenarios of a novel accelerator light source mechanism called steady-state microbunching(SSMB)were studied:longitudinal weak focusing,longitudinal strong focusing,and generalized longitudinal strong focusing(GLSF).At present,GLSF is the most promising method for realizing high-power short-wavelength coherent radiation with mild requirements on modulation laser power.Its essence is to exploit the ultrasmall natural vertical emittance of an electron beam in a planar storage ring for efficient microbunching formation,like a partial transverse-longitudinal emittance exchange in the optical laser wavelength range.Based on an in-depth investigation of related beam physics,a solution for a GLSF SSMB storage ring that can deliver 1 kW average-power EUV light is presented.The work in this paper,such as the generalized Courant–Snyder formalism,analysis of theoretical minimum emittances,transverse-longitudinal coupling dynamics,and derivation of the bunching factor and modulation strengths for laser-induced microbunching schemes,is expected to be useful not only for the development of SSMB but also for future accelerator light sources in general that demand increasingly precise electron beam phase space manipulations. 展开更多
关键词 Steady-state microbunching Extreme ultraviolet ARPES Generalized Courant-Snyder formalism Theoretical minimum emittances Longitudinal weak focusing Longitudinal strong focusing Generalized longitudinal strong focusing Transverse-longitudinal coupling Damping wiggler
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Efficient large-current conversion of CO_(2) to C_(2)H_(5)OH via a ^(*)CO-^(*)OCH_(2) coupling pathway on alkanethiol-modified Cu_(2)O array electrode
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作者 Min Zhang Weimin Wang +2 位作者 Jun Li Xun Zhu Qian Fu 《Chinese Chemical Letters》 2026年第1期729-734,共6页
Developing advanced electrocatalysts to convert CO_(2) into liquid fuels such as C_(2)H_(5)OH is critical for utilizing intermittent renewable energy.The formation of C_(2)H_(5)OH,however,is generally less favored com... Developing advanced electrocatalysts to convert CO_(2) into liquid fuels such as C_(2)H_(5)OH is critical for utilizing intermittent renewable energy.The formation of C_(2)H_(5)OH,however,is generally less favored compared with the other hydrocarbon products from Cu-based electrocatalysts.In this work,an alkanethiolmodified Cu_(2)O nanowire array(OTT-Cu_(2)O) was constructed with asymmetric Cu sites consisting of paired Cu-O and Cu-S motifs to overcome previous limitations of C_(2)H_(5)OH electrosynthesis via CO_(2)RR pathway.This catalyst achieves a high Faradaic efficiency of 45 % for CO_(2)-to-C_(2)H_(5)OH conversion at 300 m A/cm^(2),representing a more than two-fold enhancement over the Cu_(2)O electrode.Mechanistic investigations reveal that the Cu-S site exhibits distinct C-binding capability that stabilizes key intermediates(^(*)OCH_(2) and ^(*)CO),in contrast to the O-affinitive Cu-O site.The asymmetric S-Cu-O configuration promotes thermodynamically favorable asymmetric C-C coupling between ^(*)CO and ^(*)OCH_(2),forming the critical CO-OCH_(2) intermediate and facilitating C_(2)H_(5)OH production,as opposed to symmetric O-Cu-O sites that mainly generate HCOOH.This work offers an effective strategy for designing multi-active-site catalysts toward highly selective CO_(2) reduction to C_(2)H_(5)OH and provides fundamental insight into the reaction mechanism. 展开更多
关键词 CO_(2)reduction C_(2)H_(5)OH Cu_(2)O-OTT Asymmetric sites ^(*)CO-^(*)OCH_(2)coupling
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双靶磁控溅射工艺参数对AZO薄膜性能的影响
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作者 张健 于尉 +1 位作者 孙冰成 张贤旺 《真空》 2026年第1期35-39,共5页
采用双靶磁控溅射技术在石英玻璃基底上制备了AZO薄膜,通过调整溅射功率、溅射气压和衬底温度等关键工艺参数,深入研究了这些参数对AZO薄膜透光度和导电性的影响。使用紫外分光光度计与四探针测试仪等设备对ATO薄膜进行了表征分析。结... 采用双靶磁控溅射技术在石英玻璃基底上制备了AZO薄膜,通过调整溅射功率、溅射气压和衬底温度等关键工艺参数,深入研究了这些参数对AZO薄膜透光度和导电性的影响。使用紫外分光光度计与四探针测试仪等设备对ATO薄膜进行了表征分析。结果表明:随着溅射功率的增加,薄膜的透光度和电阻率均呈现下降趋势,在30 W铝靶溅射功率下透光性最好,在50 W溅射功率下电阻率最低;随着溅射气压的增大,薄膜透光度和电阻率先增加后降低,在0.7 Pa溅射气压下AZO薄膜在可见光范围内的透光性最好,透光率达到90%以上,在1.0 Pa溅射气压下电阻率最低,为43Ω·cm;在250℃的衬底温度下薄膜的性能达到最优,其在可见光范围内的平均透光度为87%,电阻率为38Ω·cm。 展开更多
关键词 azo薄膜 双靶磁控溅射 溅射功率 溅射气压 衬底温度
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Defects‑Rich Heterostructures Trigger Strong Polarization Coupling in Sulfides/Carbon Composites with Robust Electromagnetic Wave Absorption 被引量:3
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作者 Jiaolong Liu Siyu Zhang +14 位作者 Dan Qu Xuejiao Zhou Moxuan Yin Chenxuan Wang Xuelin Zhang Sichen Li Peijun Zhang Yuqi Zhou Kai Tao Mengyang Li Bing Wei Hongjing Wu Mengyang Li Bing Wei Hongjing Wu 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期528-547,共20页
Defects-rich heterointerfaces integrated with adjustable crystalline phases and atom vacancies,as well as veiled dielectric-responsive character,are instrumental in electromagnetic dissipation.Conventional methods,how... Defects-rich heterointerfaces integrated with adjustable crystalline phases and atom vacancies,as well as veiled dielectric-responsive character,are instrumental in electromagnetic dissipation.Conventional methods,however,constrain their delicate constructions.Herein,an innovative alternative is proposed:carrageenan-assistant cations-regulated(CACR)strategy,which induces a series of sulfides nanoparticles rooted in situ on the surface of carbon matrix.This unique configuration originates from strategic vacancy formation energy of sulfides and strong sulfides-carbon support interaction,benefiting the delicate construction of defects-rich heterostructures in M_(x)S_(y)/carbon composites(M-CAs).Impressively,these generated sulfur vacancies are firstly found to strengthen electron accumulation/consumption ability at heterointerfaces and,simultaneously,induct local asymmetry of electronic structure to evoke large dipole moment,ultimately leading to polarization coupling,i.e.,defect-type interfacial polarization.Such“Janus effect”(Janus effect means versatility,as in the Greek two-headed Janus)of interfacial sulfur vacancies is intuitively confirmed by both theoretical and experimental investigations for the first time.Consequently,the sulfur vacancies-rich heterostructured Co/Ni-CAs displays broad absorption bandwidth of 6.76 GHz at only 1.8 mm,compared to sulfur vacancies-free CAs without any dielectric response.Harnessing defects-rich heterostructures,this one-pot CACR strategy may steer the design and development of advanced nanomaterials,boosting functionality across diverse application domains beyond electromagnetic response. 展开更多
关键词 Defects-rich heterointerfaces Sulfides Polarization coupling Electromagnetic wave absorption
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Study on the Fluid-Solid Coupling Seepage of the Deep Tight Reservoir Based on 3D Digital Core Modeling 被引量:4
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作者 Haijun Yang Zhenzhong Cai +5 位作者 Hui Zhang Chong Sun Jing Li Xiaoyu Meng Chen Liu Chengqiang Yang 《Energy Engineering》 2025年第2期537-560,共24页
Deep tight reservoirs exhibit complex stress and seepage fields due to varying pore structures,thus the seepage characteristics are significant for enhancing oil production.This study conducted triaxial compression an... Deep tight reservoirs exhibit complex stress and seepage fields due to varying pore structures,thus the seepage characteristics are significant for enhancing oil production.This study conducted triaxial compression and permeability tests to investigate the mechanical and seepage properties of tight sandstone.A digital core of tight sandstone was built using Computed Tomography(CT)scanning,which was divided into matrix and pore phases by a pore equivalent diameter threshold.A fluid-solid coupling model was established to investigate the seepage characteristics at micro-scale.The results showed that increasing the confining pressure decreased porosity,permeability,and flow velocity,with the pore phase becoming the dominant seepage channel.Cracks and large pores closed first under increasing pressure,resulted in a steep drop in permeability.However,permeability slightly decreased under high confining pressure,which followed a first-order exponential function.Flow velocity increased with seepage pressure.And the damage mainly occurred in stress-concentration regions under low seepage pressure.Seepage behavior followed linear Darcy flow,the damage emerged at seepage entrances under high pressure,which decreased rock elastic modulus and significantly increased permeability. 展开更多
关键词 Digital core fluid-solid coupling pore structure microscopic seepage
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Efficient imidazolium salts for palladium-catalyzed Mizoroki-Heck and Suzuki-Miyaura cross-coupling reactions 被引量:2
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作者 Mojtaba Amini Mojtaba Bagherzadeh Sadegh Rostamnia 《Chinese Chemical Letters》 SCIE CAS CSCD 2013年第5期433-436,共4页
The system,Pd(OAc)_2/imidazolium salts(L_2),was found as an efficient catalyst in the Heck coupling reaction of olefins with aryl halides and Suzuki reactions of various aryl halides with aryl boronic acids under ... The system,Pd(OAc)_2/imidazolium salts(L_2),was found as an efficient catalyst in the Heck coupling reaction of olefins with aryl halides and Suzuki reactions of various aryl halides with aryl boronic acids under aerobic condition.This catalytic system demonstrates great tolerance to a wide range of groups on all substrates of aryl halides,alkenes and aryl boronic acids. 展开更多
关键词 lmidazolium salt Heck coupling reaction Suzuki coupling reaction Pd(OAc)2
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Palladium-catalyzed Suzuki-Miyaura cross-coupling reaction of organoboronic acids with N-protected 4-iodophenyl alanine linked isoxazoles 被引量:4
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作者 E.Rajanarendar G.Mohan +1 位作者 E.Kalyan Rao M.Srinivas 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第1期1-4,共4页
Suzuki-Miyaura coupling reaction of N-protected 4-iodopheyl alanine isoxazoles with arylboronic acids,catalyzed by palladium,efficiently produce benzyl-N-(4-bipheyl)-2-(3-methyl-5(E)-2-aryl-1-ethenyl-4-isoxazolyl... Suzuki-Miyaura coupling reaction of N-protected 4-iodopheyl alanine isoxazoles with arylboronic acids,catalyzed by palladium,efficiently produce benzyl-N-(4-bipheyl)-2-(3-methyl-5(E)-2-aryl-1-ethenyl-4-isoxazolyl)-amino-2-oxoethyl)carba- mates in good yields.This process is first of its kind to construct carbon-carbon bond formation having biaryl motif on amino acid linked isoxazole moiety. 展开更多
关键词 Suzuki-Miyaura coupling C-C bond formation Amino acid linked isoxazoles
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Coupling Coordination Development and Driving Factors of New Energy Vehicles and Ecological Environment in China 被引量:5
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作者 XU Zonghuang 《Wuhan University Journal of Natural Sciences》 2025年第1期79-90,共12页
Studying the coupling coordination development of new energy vehicles(NEVs)and the ecological environment in China is helpful in promoting the development of NEVs in the country and is of great significance in promoti... Studying the coupling coordination development of new energy vehicles(NEVs)and the ecological environment in China is helpful in promoting the development of NEVs in the country and is of great significance in promoting high-quality development of new energy in China.This paper constructs an evaluation index system for the development of NEVs and the ecological environment.It uses game theory combining weighting model,particle swarm optimized projection tracking evaluation model,coupling coordination degree model,and machine learning algorithms to calculate and analyze the level of coupling coordination development of NEVs and the ecological environment in China from 2010 to 2021,and identifies the driving factors.The research results show that:(i)From 2010 to 2021,the development index of NEVs in China has steadily increased from 0.085 to 0.634,while the ecological environment level index significantly rose from 0.170 to 0.884,reflecting the continuous development of China in both NEVs and the ecological environment.(ii)From 2010 to 2012,the two systems—new energy vehicle(NEV)development and the ecological environment—were in a period of imbalance and decline.From 2013 to 2016,they underwent a transition period,and from 2017 to 2021,they entered a period of coordinated development showing a trend of benign and continuous improvement.By 2021,they reached a good level of coordination.(iii)Indicators such as the number of patents granted for NEVs,water consumption per unit of GDP,and energy consumption per unit of GDP are the main driving factors affecting the coupling coordination development of NEVs and the ecological environment in China. 展开更多
关键词 new energy vehicles(NEVs) ecological environment coupling coordination development machine learning driving factors
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