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Riding the Trend of the Times with a Strong Sense of Responsibility
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作者 Wang Yi 《China International Studies》 2025年第1期5-20,共16页
In 2024,the world witnessed further transformation and instability,marked by protracted and intensified geopolitical conflicts,repeated attempts to decouple and sever supply chains,and the rapid rise of the Global Sou... In 2024,the world witnessed further transformation and instability,marked by protracted and intensified geopolitical conflicts,repeated attempts to decouple and sever supply chains,and the rapid rise of the Global South.It has become all the more clear where the once-in-a-century transformations are heading.In 2024,China acted on the blueprint drawn up at the Third Plenary Session of the 20th Central Committee of the Communist Party of China(CPC),and made big strides in deepening reform comprehensively.Marking the 75th anniversary of the founding of New China,China carried forward its great cause of national development and pressed ahead with Chinese modernization with vigor and determination. 展开更多
关键词 strong TIMES DEEPENING
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A Strong Synergy of Hengqin-Macao Tourism
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作者 ZHANG XIAO 《China Today》 2025年第3期60-61,共2页
HE Tangs,a family of three from Hebei Province in north China,were full of gasps of admiration as they went on a Hengqin-Macao bay cruise in southern China.The cruise started from Hengqin,a small island with remarkabl... HE Tangs,a family of three from Hebei Province in north China,were full of gasps of admiration as they went on a Hengqin-Macao bay cruise in southern China.The cruise started from Hengqin,a small island with remarkable economic achievements on the Chinese mainland,and then went past the picturesque Macao Special Administrative Region.The passengers frantically clicked away at the passing landmarks-the 338-meter Macao Tower,one of Macao’s most iconic architectures,the four spectacular sea-crossing bridges connecting Macao Peninsula and Macao’s Taipa Island,and of course the Hong Kong-Zhu-hai-Macao Bridge,the longest bridge-cum-tunnel sea crossing in the world linking Hong Kong with the city of Zhuhai on the mainland. 展开更多
关键词 MAINLAND strong MACAO
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Correction:Defects-Rich Heterostructures Trigger Strong Polarization Coupling in Sulfides/Carbon Composites with Robust Electromagnetic Wave Absorption
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作者 Jiaolong Liu Siyu Zhang +11 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 《Nano-Micro Letters》 2025年第4期290-290,共1页
Correction to:Nano-Micro Lett.(2025)17:24 https://doi.org/10.1007/s40820-024-01515-0 Following publication of the original article[1],the authors reported the author list needed to be updated because the last three au... Correction to:Nano-Micro Lett.(2025)17:24 https://doi.org/10.1007/s40820-024-01515-0 Following publication of the original article[1],the authors reported the author list needed to be updated because the last three author names were duplicated.The correct author list has been provided in this Correction.The original article[1]has been corrected. 展开更多
关键词 strong Polarization Defects
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Parameter optimization of the observation system for the South Yellow Sea strong shielding layer based on seismic illumination analysis
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作者 Yang Jia-Jia Chen Jian-Wen +5 位作者 Huang Fu-Qiang Yan Zhong-Hui Lei Bao-Hua Wang Xiao-Jie Xu Hua-Ning Liu Hong 《Applied Geophysics》 2025年第1期84-98,233,共16页
The seismic data of the Laoshan Uplift in the South Yellow Sea Basin reveal a low signal-tonoise ratio and low refl ection signal energy in the deep Mesozoic–Paleozoic strata.The main reason is that the Mesozoic-Pale... The seismic data of the Laoshan Uplift in the South Yellow Sea Basin reveal a low signal-tonoise ratio and low refl ection signal energy in the deep Mesozoic–Paleozoic strata.The main reason is that the Mesozoic-Paleozoic marine carbonate rock strata are directly covered by the Cenozoic terrestrial clastic rock strata,which form a strong shielding layer.To obtain the reflection signals of the strata below the strong shielding layer,a one-way wave equation bidirectional illumination analysis of the main observation system parameters was conducted by analyzing the mechanism of the strong shielding layer.Low-frequency seismic sources are assumed to have a high illumination intensity on the reflection layer below the strong shielding layer.Accordingly,optimized acquisition parameter suggestions were proposed,and reacquisition was performed at the existing survey line locations in the Laoshan Uplift area.The imaging of the newly acquired data in the middle and deep layers was drastically improved.It revealed the unconformity between the Sinian and Cambrian under the strong shielding layer.The study yielded new insights into the tectonic and sedimentary evolution of the Lower Paleozoic in the South Yellow Sea. 展开更多
关键词 illumination analysis acquisition parameters Laoshan Uplift strong shielding layer
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On the Strongly Hopfian Acts over Semigroups
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作者 Ksenya Anatolyevna Kolesnikova Igor Borisovich Kozhukhov 《Applied Mathematics》 2025年第2期183-189,共7页
We find the necessary and sufficient conditions on a coproduct of connected acts over a semigroup to be strongly hopfian. From this, we deduce the conditions of the strong hopfness for unitary acts over groups. Moreov... We find the necessary and sufficient conditions on a coproduct of connected acts over a semigroup to be strongly hopfian. From this, we deduce the conditions of the strong hopfness for unitary acts over groups. Moreover, we prove that a finite coproduct of strongly hopfian acts over an arbitrary semigroup is strongly hopfian. 展开更多
关键词 Act Over Semigroup Act Over Group strongly Hopfian Act
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Enhanced amplified spontaneous emission via splitted strong coupling mode in large-area plasmonic cone lattices
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作者 Jiazhi Yuan Jiang Hu +7 位作者 Yan Zheng Hao Wei Jiamin Xiao Yi Wang Xuchao Zhao Ye Xiang Yong Lei Wenxin Wang 《Opto-Electronic Science》 2025年第2期16-24,共9页
Periodic metal nanoarrays serving as cavities can support directional-tunable amplified spontaneous emission that goes beyond the diffraction limit due to the hybrid states of surface plasmons and Bloch surface waves.... Periodic metal nanoarrays serving as cavities can support directional-tunable amplified spontaneous emission that goes beyond the diffraction limit due to the hybrid states of surface plasmons and Bloch surface waves.Most of these modes'interactions remain within the weak coupling regime,yet strong coupling is also anticipated to occur.In this work,we present an intriguing case of amplified spontaneous emission(ASE),amplified by the splitting upper polariton mode within a strong coupling system,stemming from a square lattice of plasmonic cone lattices(PCLs).The PCLs are fabricated using an anodized aluminum oxide membrane(AAO),which facilitates strong coupling between surface plasmons and Bloch surface wave modes,with the maximum Rabi splitting observed at 0.258 eV for the sample with an aspect ratio of 0.33.A 13.5-fold increase in amplified spontaneous emission is recorded when the emission from Nile Red coincides with this flat energy branch of upper polariton,which exhibits a high photon density of states.Reduced group velocity can prolong photon lifetime and boost the probability of light-matter interaction.The observed ASE phenomenon in this strong coupling plasmonic system widens the scope for applications in nanolasing and polariton lasing. 展开更多
关键词 strong coupling nanocone array surface plasmon polariton localized surface plasmon amplified spontaneous emission
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Vibration safety assessment and parameter analysis of buried oil pipelines based on vibration isolation holes under strong surface impact
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作者 Wang Guobo Mei Hua +4 位作者 Wang Jianning He Wei Yin Yao Zhai Yuxin Zuo Pengfei 《Earthquake Engineering and Engineering Vibration》 2025年第1期69-82,共14页
Strong surface impact will produce strong vibration,which will pose a threat to the safety of nearby buried pipelines and other important lifeline projects.Based on the verified numerical method,a comprehensive numeri... Strong surface impact will produce strong vibration,which will pose a threat to the safety of nearby buried pipelines and other important lifeline projects.Based on the verified numerical method,a comprehensive numerical parameter analysis is conducted on the key influencing factors of the vibration isolation hole(VIH),which include hole diameter,hole net spacing,hole depth,hole number,hole arrangement,and soil parameters.The results indicate that a smaller ratio of net spacing to hole diameter,the deeper the hole,the multi-row hole,the hole adoption of staggered arrangements,and better site soil conditions can enhance the efficiency of the VIH barrier.The average maximum vibration reduction efficiency within the vibration isolation area can reach 42.2%.The vibration safety of adjacent oil pipelines during a dynamic compaction projection was evaluated according to existing standards,and the measurement of the VIH was recommended to reduce excessive vibration.The single-row vibration isolation scheme and three-row staggered arrangement with the same hole parameters are suggested according to different cases.The research findings can serve as a reference for the vibration safety analysis,assessment,and control of adjacent underground facilities under the influence of strong surface impact loads. 展开更多
关键词 vibration isolation hole buried oil pipeline strong surface impact vibration velocity vibration safety assessment
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A novel detection method for warhead fragment targets in optical images under dynamic strong interference environments
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作者 Guoyi Zhang Hongxiang Zhang +4 位作者 Zhihua Shen Deren Kong Chenhao Ning Fei Shang Xiaohu Zhang 《Defence Technology(防务技术)》 2025年第1期252-270,共19页
A measurement system for the scattering characteristics of warhead fragments based on high-speed imaging systems offers advantages such as simple deployment,flexible maneuverability,and high spatiotemporal resolution,... A measurement system for the scattering characteristics of warhead fragments based on high-speed imaging systems offers advantages such as simple deployment,flexible maneuverability,and high spatiotemporal resolution,enabling the acquisition of full-process data of the fragment scattering process.However,mismatches between camera frame rates and target velocities can lead to long motion blur tails of high-speed fragment targets,resulting in low signal-to-noise ratios and rendering conventional detection algorithms ineffective in dynamic strong interference testing environments.In this study,we propose a detection framework centered on dynamic strong interference disturbance signal separation and suppression.We introduce a mixture Gaussian model constrained under a joint spatialtemporal-transform domain Dirichlet process,combined with total variation regularization to achieve disturbance signal suppression.Experimental results demonstrate that the proposed disturbance suppression method can be integrated with certain conventional motion target detection tasks,enabling adaptation to real-world data to a certain extent.Moreover,we provide a specific implementation of this process,which achieves a detection rate close to 100%with an approximate 0%false alarm rate in multiple sets of real target field test data.This research effectively advances the development of the field of damage parameter testing. 展开更多
关键词 Damage parameter testing Warhead fragment target detection High-speed imaging systems Dynamic strong interference disturbance suppression Variational bayesian inference Motion target detection Faint streak-like target detection
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Strong coupling and catenary field enhancement in the hybrid plasmonic metamaterial cavity and TMDC monolayers 被引量:2
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作者 Andergachew Mekonnen Berhe Khalil As’ham +2 位作者 Ibrahim Al-Ani Haroldo T.Hattori Andrey E.Miroshnichenko 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第5期20-32,共13页
Strong coupling between resonantly matched surface plasmons of metals and excitons of quantum emitters results in the formation of new plasmon-exciton hybridized energy states.In plasmon-exciton strong coupling,plasmo... Strong coupling between resonantly matched surface plasmons of metals and excitons of quantum emitters results in the formation of new plasmon-exciton hybridized energy states.In plasmon-exciton strong coupling,plasmonic nanocavities play a significant role due to their ability to confine light in an ultrasmall volume.Additionally,two-dimensional transition metal dichalcogenides(TMDCs) have a significant exciton binding energy and remain stable at ambient conditions,making them an excellent alternative for investigating light-matter interactions.As a result,strong plasmon-exciton coupling has been reported by introducing a single metallic cavity.However,single nanoparticles have lower spatial confinement of electromagnetic fields and limited tunability to match the excitonic resonance.Here,we introduce the concept of catenary-shaped optical fields induced by plasmonic metamaterial cavities to scale the strength of plasmon-exciton coupling.The demonstrated plasmon modes of metallic metamaterial cavities offer high confinement and tunability and can match with the excitons of TMDCs to exhibit a strong coupling regime by tuning either the size of the cavity gap or thickness.The calculated Rabi splitting of Au-MoSe_2 and Au-WSe_2 heterostructures strongly depends on the catenary-like field enhancement induced by the Au cavity,resulting in room-temperature Rabi splitting ranging between 77.86 and 320 me V.These plasmonic metamaterial cavities can pave the way for manipulating excitons in TMDCs and operating active nanophotonic devices at ambient temperature. 展开更多
关键词 catenary-shaped field enhancement strong coupling PLASMON EXCITON Rabi splitting
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Strong metal–support interaction boosts the electrocatalytic hydrogen evolution capability of Ru nanoparticles supported on titanium nitride 被引量:2
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作者 Xin Wang Xiaoli Yang +7 位作者 Guangxian Pei Jifa Yang Junzhe Liu Fengwang Zhao Fayi Jin Wei Jiang Haoxi Ben Lixue Zhang 《Carbon Energy》 SCIE EI CAS CSCD 2024年第1期245-254,共10页
Ruthenium(Ru)has been regarded as one of the most promising alternatives to substitute Pt for catalyzing alkaline hydrogen evolution reaction(HER),owing to its inherent high activity and being the cheapest platinum-gr... Ruthenium(Ru)has been regarded as one of the most promising alternatives to substitute Pt for catalyzing alkaline hydrogen evolution reaction(HER),owing to its inherent high activity and being the cheapest platinum-group metal.Herein,based on the idea of strong metal–support interaction(SMSI)regulation,Ru/TiN catalysts with different degrees of TiN overlayer over Ru nanoparticles were fabricated,which were applied to the alkaline electrolytic water.Characterizations reveal that the TiN overlayer would gradually encapsulate the Ru nanoparticles and induce more electron transfer from Ru nanoparticles to TiN support by the Ru–N–Ti bond as the SMSI degree increased.Further study shows that the exposed Ru–TiN interfaces greatly promote the H_(2) desorption capacity.Thus,the Ru/TiN-300 with a moderate SMSI degree exhibits excellent HER performance,with an overpotential of 38 mV at 10 mA cm^(−2).Also,due to the encapsulation role of TiN overlayer on Ru nanoparticles,it displays super long-term stability with a very slight potential change after 24 h.This study provides a deep insight into the influence of the SMSI effect between Ru and TiN on HER and offers a novel approach for preparing efficient and stable HER electrocatalysts through SMSI engineering. 展开更多
关键词 electronic structure hydrogen evolution reaction RUTHENIUM strong metal-support interaction titanium nitride
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Achieving asymmetric redox chemistry for oxygen evolution reaction through strong metal-support interactions 被引量:1
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作者 Shihao Wang Meiling Fan +4 位作者 Hongfei Pan Jiahui Lyu Jinsong Wu Haolin Tang Haining Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第9期526-535,共10页
Water electrolysis poses a significant challenge for balancing catalytic activity and stability of oxygen evolution reaction(OER)electrocatalysts.In this study,we address this challenge by constructing asymmetric redo... Water electrolysis poses a significant challenge for balancing catalytic activity and stability of oxygen evolution reaction(OER)electrocatalysts.In this study,we address this challenge by constructing asymmetric redox chemistry through elaborate surface OO–Ru–OH and bulk Ru–O–Ni/Fe coordination moieties within single-atom Ru-decorated defective NiFe LDH nanosheets(Ru@d-NiFe LDH)in conjunction with strong metal-support interactions(SMSI).Rigorous spectroscopic characterization and theoretical calculations indicate that single-atom Ru can delocalize the O 2p electrons on the surface and optimize d-electron configurations of metal atoms in bulk through SMSI.The^(18)O isotope labeling experiment based on operando differential electrochemical mass spectrometry(DEMS),chemical probe experiments,and theoretical calculations confirm the encouraged surface lattice oxygen,stabilized bulk lattice oxygen,and enhanced adsorption of oxygen-containing intermediates for bulk metals in Ru@d-NiFe LDH,leading to asymmetric redox chemistry for OER.The Ru@d-NiFe LDH electrocatalyst exhibits exceptional performance with an overpotential of 230 mV to achieve 10 mA cm^(−2)and maintains high robustness under industrial current density.This approach for achieving asymmetric redox chemistry through SMSI presents a new avenue for developing high-performance electrocatalysts and instills confidence in its industrial applicability. 展开更多
关键词 Reaction redox chemistry strong metal-support interactions Layered double hydroxides ELECTROCATALYSTS Water electrolysis
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Analysis of Strong Coupling Constant with Machine Learning and Its Application
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作者 王晓云 董晨 刘翔 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第3期15-22,共8页
We investigate the nature of the strong coupling constant and related physics.Through the analysis of accumulated experimental data around the world,we employ the ability of machine learning to unravel its physical la... We investigate the nature of the strong coupling constant and related physics.Through the analysis of accumulated experimental data around the world,we employ the ability of machine learning to unravel its physical laws.The result of our efforts is a formula that captures the expansive panorama of the distribution of the strong coupling constant across the entire energy range. 展开更多
关键词 strong COUPLING accumulated
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Publisher Correction to:Strongly Coupled 2D Transition Metal Chalcogenide‑MXene‑Carbonaceous Nanoribbon Heterostructures with Ultrafast Ion Transport for Boosting Sodium/Potassium Ions Storage
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作者 Junming Cao Junzhi Li +5 位作者 Dongdong Li Zeyu Yuan Yuming Zhang Valerii Shulga Ziqi Sun Wei Han 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第6期458-458,共1页
Due to the technical fault,a wrong version of the paper was uploaded.The content of the article was not affected,but the layout of the article was affected.The original article has been corrected.
关键词 Transition strongLY STORAGE
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Correction to:Error Calculation of Large-Amplitude Internal Solitary Waves Within the Pycnocline Introduced by the Strong Stratification Approximation
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作者 Cunguo Xu Zhan Wang Masoud Hayatdavoodi 《哈尔滨工程大学学报(英文版)》 CSCD 2024年第1期247-247,共1页
In the original publication the third author name is published incorrectly as“Hayatdavoodi Masoud”.The correct author name should be read as“Masoud Hayatdavoodi”.The correct author name is available in this correc... In the original publication the third author name is published incorrectly as“Hayatdavoodi Masoud”.The correct author name should be read as“Masoud Hayatdavoodi”.The correct author name is available in this correction. 展开更多
关键词 strong Internal CORRECTION
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Evolutionary dynamics of tax-based strong altruistic reward andpunishment in a public goods game
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作者 Zhi-Hao Yang Yan-Long Yang 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期247-257,共11页
In public goods games, punishments and rewards have been shown to be effective mechanisms for maintaining individualcooperation. However, punishments and rewards are costly to incentivize cooperation. Therefore, the g... In public goods games, punishments and rewards have been shown to be effective mechanisms for maintaining individualcooperation. However, punishments and rewards are costly to incentivize cooperation. Therefore, the generation ofcostly penalties and rewards has been a complex problem in promoting the development of cooperation. In real society,specialized institutions exist to punish evil people or reward good people by collecting taxes. We propose a strong altruisticpunishment or reward strategy in the public goods game through this phenomenon. Through theoretical analysis and numericalcalculation, we can get that tax-based strong altruistic punishment (reward) has more evolutionary advantages thantraditional strong altruistic punishment (reward) in maintaining cooperation and tax-based strong altruistic reward leads toa higher level of cooperation than tax-based strong altruistic punishment. 展开更多
关键词 evolutionary game theory strong altruism PUNISHMENT REWARD
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Silica-modified Pt/TiO_(2) catalysts with tunable suppression of strong metal-support interaction for cinnamaldehyde hydrogenation
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作者 Zhengjian Hou Yuanyuan Zhu +6 位作者 Hua Chi Li Zhao Huijie Wei Yanyan Xi Lishuang Ma Xiang Feng Xufeng Lin 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第6期189-198,共10页
Tuning Strong Metal-support Interactions(SMSI)is a key strategy to obtain highly active catalysts,but conventional methods usually enable TiO_(x) encapsulation of noble metal components to minimize the exposure of nob... Tuning Strong Metal-support Interactions(SMSI)is a key strategy to obtain highly active catalysts,but conventional methods usually enable TiO_(x) encapsulation of noble metal components to minimize the exposure of noble metals.This study demonstrates a catalyst preparation method to modulate a weak encapsulation of Pt metal nanoparticles(NPs)with the supported TiO_(2),achieving the moderate suppression of SMSI effects.The introduction of silica inhibits this encapsulation,as reflected in the characterization results such as XPS and HRTEM,while the Ti^(4+) to Ti^(3+) conversion due to SMSI can still be found on the support surface.Furthermore,the hydrogenation of cinnamaldehyde(CAL)as a probe reaction revealed that once this encapsulation behavior was suppressed,the adsorption capacity of the catalyst for small molecules like H_(2) and CO was enhanced,which thereby improved the catalytic activity and facilitated the hydrogenation of CAL.Meanwhile,the introduction of SiO_(2) also changed the surface structure of the catalyst,which inhibited the occurrence of the acetal reaction and improved the conversion efficiency of C=O and C=C hydrogenation.Systematic manipulation of SMSI formation and its consequence on the performance in catalytic hydrogenation reactions are discussed. 展开更多
关键词 Pt catalyst Silica modification HYDROGENATION CINNAMALDEHYDE strong metal-support interaction
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Excitation and ionization of OCS molecules in strong UV and NIR laser fields
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作者 师慧军 刘洋 +2 位作者 孙添 吕航 徐海峰 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期285-291,共7页
Rydberg state excitation(RSE) is a highly non-linear physical phenomenon that is induced by the ionization of atoms or molecules in strong femtosecond laser fields. Here we observe that both parent and fragments(S, C,... Rydberg state excitation(RSE) is a highly non-linear physical phenomenon that is induced by the ionization of atoms or molecules in strong femtosecond laser fields. Here we observe that both parent and fragments(S, C, OC) of the triatomic molecule carbonyl sulfide(OCS) can survive strong 800 nm or 400 nm laser fields in high Rydberg states. The dependence of parent and fragment RSE yields on laser intensity and ellipticity is investigated in both laser fields, and the results are compared with those for strong-field ionization. Distinctly different tendencies for laser intensity and ellipticity are observed for fragment RSE compared with the corresponding ions. The mechanisms of RSE and strong-field ionization of OCS molecules in different laser fields are discussed based on the experimental results. Our study sheds some light on the strong-field excitation and ionization of molecules irradiated by femtosecond NIR and UV laser fields. 展开更多
关键词 Rydberg state excitation strong field carbonyl sulfide IONIZATION
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THE GLOBAL EXISTENCE OF STRONG SOLUTIONS TO THERMOMECHANICAL CUCKER-SMALE-STOKES EQUATIONS IN THE WHOLE DOMAIN
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作者 邹委员 《Acta Mathematica Scientia》 SCIE CSCD 2024年第3期887-908,共22页
We study the global existence and uniqueness of a strong solution to the kinetic thermomechanical Cucker-Smale(for short,TCS) model coupled with Stokes equations in the whole space.The coupled system consists of the k... We study the global existence and uniqueness of a strong solution to the kinetic thermomechanical Cucker-Smale(for short,TCS) model coupled with Stokes equations in the whole space.The coupled system consists of the kinetic TCS equation for a particle ensemble and the Stokes equations for a fluid via a drag force.In this paper,we present a complete analysis of the existence of global-in-time strong solutions to the coupled model without any smallness restrictions on the initial data. 展开更多
关键词 thermomechanical Cucker-Smale model Stokes equations strong solutions global existence
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Atomically dispersed calcium as solid strong base catalyst with high activity and stability
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作者 Xiang-Bin Shao Zhi-Wei Xing +5 位作者 Si-Yu Liu Ke-Xin Miao Shi-Chao Qi Song-Song Peng Xiao-Qin Liu Lin-Bing Sun 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第10期1619-1626,共8页
Solid strong base catalysts are highly attractive for diverse reactions owing to their advantages of neglectable corrosion,facile separation,and environmental friendliness.However,their widespread applications are imp... Solid strong base catalysts are highly attractive for diverse reactions owing to their advantages of neglectable corrosion,facile separation,and environmental friendliness.However,their widespread applications are impeded by basic components aggregation and low stability.In this work,we fabricate single calcium atoms on graphene(denoted as Ca1/G)by use of a redox strategy for the first time,producing solid strong base catalyst with high activity and stability.The precursor Ca(NO_(3))_(2)is first reduced to CaO at 400℃ by the support graphene,forming CaO/G with conventional basic sites,and the subsequent reduction at 850℃results in the generation of Ca1/G with atomically dispersed Ca.Various characterizations reveal that Ca single atoms are anchored on graphene in tetra-coordination(Ca-C_(2)-N_(2))where N is in situ doped from Ca(NO_(3))_(2).The atomically dispersed Ca,along with their anchoring on the support,endow Ca1/G with high activity and stability toward the transesterification reaction of ethylene carbonate with methanol.The turnover frequency value reaches 128.0 h^(-1)on Ca1/G,which is much higher than the traditional counterpart CaO/G and various reported solid strong bases(2.9-46.2 h^(-1)).Moreover,the activity of Ca1/G is well maintained during 5 cycles,while 60%of activity is lost for the conventional analogue CaO/G due to the leaching of Ca. 展开更多
关键词 Solid strong base Single Ca atoms Heterogeneous catalysts TRANSESTERIFICATION REACTION
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Unification of Gravitational and Strong Interaction Fields Using Partial Gauge Symmetry
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作者 Young Hwan Yun Kiho Jang 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第2期515-533,共19页
We propose the new field potential by maintaining both the symmetry of the scalar gauge and the conservation law keeping N?ether’s theorem, while disregarding the symmetry of the vector gauge. The new potential forms... We propose the new field potential by maintaining both the symmetry of the scalar gauge and the conservation law keeping N?ether’s theorem, while disregarding the symmetry of the vector gauge. The new potential forms like the well-type potential where a particle behaves almost freely but is very hard to escape without external energy, which can be interpreted as local confinement and asymptotic freedom. By assuming a 2-dimensional metric tensor in 4-dimensional space-time, we suggest the existence of 3 kinds of particles that resemble QCD with 3 color charges. We also show that the mass term exists but comes to zero and derive the charge and spin values. We can regard the particle with this new potential as a gluon, and the interaction in this well-type potential as a strong interaction for the properties of mass, charge, spin, and its behavior. We suggest the eight-fold way with this new particle, which is similar to the existing method based on SU (3) symmetry. Even though the strong interaction has been analyzed in the standard model and string theory, we build a new consistent model based on the theory of relativity including Riemann geometry, and show the unification of gravitational and strong interactional field. 展开更多
关键词 strong Interaction Gauge Symmetry RELATIVITY QCD CONFINEMENT Asymptotic Freedom
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