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Single-atom catalysis for organic reactions

Chinese Chemical Letters 2023年第6期34卷 121-129页

作者： Hanyu hu Jiangbo xi Key Laboratory of Novel Biomass-Based Environmental and Energy Materials in Petroleum and Chemical Industry Key Laboratory of Green Chemical Engineering Process of Ministry of EducationEngineering Research Center of Phosphorus Resources Development and Utilization of Ministry of EducationHubei Key Laboratory of Novel Reactor and Green Chemical TechnologySchool of Chemistry and Environmental EngineeringWuhan Institute of TechnologyWuhan 430205China

Metal-based catalysis,including homogeneous and heterogeneous catalysis,plays a significant role in the modern chemical *** catalysis is widely used due to the high efficiency,easy catalyst separation and ***,the metal-utilization efficiency for conventional heterogeneous catalysts needs further improvement compared to homogeneous *** tackle this,the pursing of heterogenizing homogeneous catalysts has always been attractive but *** a recently emerging class of catalytic material,single-atom catalysts(SACs)are expected to bridge homogeneous and heterogeneous catalytic process in organic reactions and have arguably become the most active new frontier in catalysis *** this review,a brief introduction and development history of single-atom catalysis and SACs involved organic reactions are *** addition,recent advances in SACs and their practical applications in organic reactions such as oxidation,reduction,addition,coupling reaction,and other organic reactions are thoroughly *** understand structure-property relationships of single-atom catalysis in organic reactions,active sites or coordination structure,metal atom-utilization efficiency(e.g.,turnover frequency,TOF calculated based on active metal)and catalytic performance(e.g.,conversion and selectivity)of SACs are comprehensively ***,the application limitations,development trends,future challenges and perspective of SAC for organic reaction are discussed.

关键词： Single-atom catalysis Active site Metal utilization Organic reaction Catalytic performance

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Jnconventional Geometric Phase Gate with Superconducting Quantum Interference Device Qubits in Cavity QED

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Communications in Theoretical Physics 2008年第4期49卷 913-918页

作者： YANG Wen-xing CHEN ai-xi Department of Physics Southeast University Nanjing 210096 China State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Center for Cold Atom Physics Wuhan Institute of Physics and Mathematics the Chinese Academy of Sciences Wuhan 430071 China Department of Physics East China Jiaotong University Nanchang 330013 China

In the system with superconducting quantum interference devices （SQUID） in cavity, a scheme for constructing two-qubit quantum phase gate via a conventional geometric phase-shift is proposed by using a quantized cavity field and classical microwave pulses. In this scheme, the gate operation is realized in the subspace spanned by the two lower flux states of the SQUID system mud the population operator of the excited state has no effect on it. Thus the effect of decoherence caused from the levels of the SQUID system is possible to minimize. Under cavity decay, our strictly numerical simulation shows that it is also possible to realize the unconventional geometric phase gate. The experimental feasibility is discussed in detail.

关键词： superconducting quantum interference devices cavity QED geometric quantum gates

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Influences of pouring temperature and cooling rate on microstructure and mechanical properties of casting Al-Si-Cu aluminum alloy

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Acta Metallurgica Sinica(English Letters) 2012年第4期25卷 272-278页

作者： xiaowu hu Fanrong ai Hong YAN School of Mechanical Electrical Engineering Nanchang UniversityNanchang 330031China

This paper investigated the influences of pouring temperature and cooling rate on the microstructure development and mechanical properties for casting A1-Si-Cu aluminum alloy. The microstructure of the as-cast samples was characterized by an optical microscope. The results showed that the dendrite arm spacing （DAS,）,） is well refined by pouring at a higher temperature. The A decreases with increasing pouring temperature due to the multiplication of the nucleation sites in the superheating liquid melt, and the mechanical properties, such as microhardness and ultimate tensile strength increase correspondingly, while the elongation decreases. The relationships between microhardness and 3, for the samples cooled in metal mould and sand mould, are given as HV：l18.9 - 1.246A and HV=l15.2- 1.029A, respectively. The effects of the cooling rate controlled by using permanent mould casting and sand mould casing processes （the cooling medium is air and sand, respectively） on the dendrite arm spacing and mechanical properties are similar to the effect of the pouring temperature.

关键词： Pouring temperature Cooling rate Microstructure Aluminumalloy Mechanical property

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Parameter Processes of a Strong Laser in Partially Stripped Plasmas

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Chinese Physics Letters 2000年第12期17卷 893-895页

作者： hu xi-Wei Department of Modern Physics University of Science and Technology of ChinaHefei 230026

The effects of the nonlinear polarization in a partially stripped plasma on the parameter processes of a strong laser are discussed. The nonlinear mode coupling equations of stimulated Raman scattering (SRS) are derived. The linear instability growth rates of SRS and stimulated Brillouin scattering (SBS) are given. When the pump wave intensity I0 > 1017 W/cm2, the third order susceptibility associated with bound electrons will reduce the SRS and SBS linear growth rate enormous1y. In addition, the nonlinear susceptibility can affect the nonlinear evolution of SRS and SBS significantly.

关键词： nonlinear susceptibility Parameter

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Government environmental control measures on CO_(2) emission during the 2014 Youth Olympic Games in Nanjing:Perspectives from a top-down approach

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Journal of Environmental Sciences 2022年第3期34卷 165-178页

作者： Cheng hu Cheng Liu Ning hu Jun Hong xinyue ai College of Biology and the Environment Joint Center for sustainable Forestry in Southern ChinaNanjing Forestry UniversityNanjing 210037China Yale-NUIST Center on Atmospheric Environment International Joint Laboratory on Climate and Environment Change(ILCEC)Nanjing University of InformationScience&TechnologyNanjing 210044China Jiangxi Province Key Laboratory of the Causes and Control of Atmospheric Pollution/School of Water Resources and Environmental Engineering East China University of TechnologyNanchang 330013China National Key Laboratory on Electromagnetic Environmental Effects and Electro-Optical Engineering Army Engineering UniversityNanjing 210022China

Strict air pollution control measures were conducted during the Youth Olympic Games(YOG)period at Nanjing city and surrounding areas in August *** event provides a unique chance to evaluate the effect of government control measures on regional atmospheric pollution and greenhouse gas *** previous studies have observed significant reductions of atmospheric pollution species and improvement in air quality,while no study has quantified its synergism on anthropogenic CO_(2)emissions,which can be coreduced with air *** better understand to what extent these pollution control measures have reduced anthropogenic CO_(2)emissions,we conducted atmospheric CO_(2)measurements at the suburban site in Nanjing city from 1^(st) July to 30^(th) September 2014 and 1^(st) August to 31^(st) August 2015,obvious decrease in atmospheric CO_(2)was observed between YOG and the rest *** coupling the a prioriemission inventory with atmospheric transport model,we applied the scale factor Bayesian inversion approach to derive the posteriori CO_(2)emissions in YOG period and regular *** indicate CO_(2)emissions from power industry decreased by 45%,and other categories also decreased by 16%for manufacturing combusting,and 37%for non-metallic mineral *** total anthropogenic CO_(2)emissions were 9.8(±3.6)×10^(9) kg/month CO_(2) for regular period and decreased to 6.2(±1.9)×10^(9) kg/month during the YOG period in Nanjing city,with a 36.7%*** scaling up to whole Jiangsu Province,anthropogenic CO_(2)emissions were 7.1(±2.4)×10^(10) kg/month CO_(2)for regular period and decreased to 4.4(±1.2)×10^(10)kg/month CO_(2) during the YOG period,yielding a 38.0%reduction.

关键词： Carbon dioxide Reduction measures Anthropogenic emissions Bayesian inversion

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Mean Index for Non-periodic Orbits in Hamiltonian Systems

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Acta Mathematica Sinica,English Series 2022年第1期38卷 291-310页

作者： xi Jun hu Li WU School of Mathematics Shandong UniversityJi’nan 250100P.R.China

In this paper,we define mean index for non-periodic orbits in Hamiltonian systems and study its *** general,the mean index is an interval in R which is uniformly continuous on the *** show that the index interval is a point for a quasi-periodic *** mean index can be considered as a generalization of rotation number defined by Johnson and Moser in the study of almost periodic Schr¨odinger *** by their works,we study the relation of Fredholm property of the linear operator and the mean index at the end of the paper.

关键词： Mean index Maslov-type index quasi-periodic orbit Fredholm operator

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Advancing Modernisation Through Exchanges

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ChinAfrica 2025年第1期17卷 16-17页

作者： ZHOU QIAN hu LANYIN Institute of African Studies Zhejiang Normal University Zhejiang Normal University

In his keynote speech at the open-ing ceremony of the Beijing Summit of the Forum on China Africa Cooperation(FOCAC)in September 2024,Chinese President xi Jinping emphasised that China will enhance people-to-people and cultural exchanges with Africa,champion mutual respect,inclusiveness and coexistence of di"erent civilisations on the way to modernisation,and strive together for more fruitful outcomes under the Global Civilisation Initiative.

关键词： mutual Africa fruitful

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Nonlinear Evolutions of Stimulated Raman and Brillouin Scattering Processes in Partially Stripped-Ion Plasmas

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Chinese Physics Letters 2001年第9期18卷 1230-1233页

作者： hu Ye-Min hu xi-Wei Departmentof Electrical Engineering Huazhong University of Science and TechnologyWuhan 430074 Department of Modern Physics University of Science and Technology of ChinaHefei 230026

Numerical analyses for the nonlinear evolutions of stimulated Raman scattering (SRS) and stimulated Brillouin scattering (SBS) processes are given. Various effects of the second- and third-order nonlinear susceptibilities on the SRS and SBS processes are studied. The nonlinear evolutions of SRS and SBS processes are atfected more efficiently than their linear growth rates by the nonlinear susceptibility.

关键词： Brillouin nonlinear Nonlinear

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Analysis of level structure and monopole effects in Ca isotopes

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Nuclear Science and Techniques 2024年第10期35卷 161-167页

作者： Jin Li ai-xi Chen Amir Jalili Han-Kui Wang School of Science Zhejiang Sci-Tech UniversityHangzhou 310018China

Understanding the properties of nuclei near the double magic nucleus^(40)Ca is crucial for both nuclear theory and *** this study,Ca isotopes were investigated using an extended pairing-plus-quadrupole model with monopole *** negative-parity states of^(44)Ca were coupled with the intruder orbital g_(9/2)at 4 *** values of E_(4+)/E_(2+)agree well with experimental trend from^(42)Ca to^(50)Ca,considering monopole effects between νf_(7/2)and νp_(3/2)(νf_(5/2)).This monopole effect,determined from data of^(48)Ca and^(50)Ca,supports the proposed new nuclear magic number N=34 by predicting a high-energy 2^(+)state in^(54)Ca.

关键词： Shell model Doubly magic Isotopes Monopole effects Level structure

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Investigation on Surface Plasmon Polaritons and Localized Surface Plasmon Production Mechanism in Micro-Nano Structures

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Journal of Electronic Science and Technology 2022年第1期20卷 20-29页

作者： Ling-xi hu Min hu Sheng-Gang Liu Terahertz Research Center School of Electronic Science and EngineeringUniversity of Electronic Science and Technology of ChinaChengdu 610054 Key Laboratory of Terahertz Technology(Ministry of Education) University of Electronic Science and Technology of ChinaChengdu 610054

The simulation mechanism of surface plasmon polaritons(SPPs)and localized surface plasmon(LSP)in different structures was studied,including the Au reflection grating(Au grating),Au substrate with dielectric ribbons grating(Au substrate grating),and pure electric conductor(PEC)substrate with Au ribbons grating(Au ribbons grating).And the characteristics of the Smith-Purcell radiation in these structures were *** results show that SPPs are excited on the bottom surface of Au substrate grating grooves and LSP is stimulated on the upper surface both of Au ribbons grating grooves and Au grating *** to the irreconcilable contradiction between optimizing the grating diffraction radiation efficiency and optimizing the SPPs excitation efficiency in the Au substrate grating,only 40-times enhancement of the radiation intensity was obtained by excited ***,the LSP enhanced structure overcomes the above problem and gains much better radiation enhancement ability,with about 200-times enhancement obtained in the Au ribbons grating and more than 500-times enhancement obtained in the Au *** results presented here provide a way of developing miniature,integratable,tunable,high-power-density radiation sources from visible light to ultraviolet rays at room temperature.

关键词： Coherent radiation high-power radiation localized surface plasmon(LSP) micro-nano structure Smith-Purcell radiation surface plasmon polaritons(SPPs)

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