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Heterogeneous data-driven aerodynamic modeling based on physical feature embedding

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Chinese Journal of Aeronautics 2024年第3期37卷 1-6页

作者： Weiwei ZHANG xuhao peng Jiaqing KOU xu WANG School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China Institute of Aerodynamics RWTH Aachen UniversityAachen 52062Germany

Aerodynamic surrogate modeling mostly relies only on integrated loads data obtained from simulation or experiment,while neglecting and wasting the valuable distributed physical information on the *** make full use of both integrated and distributed loads,a modeling paradigm,called the heterogeneous data-driven aerodynamic modeling,is *** essential concept is to incorporate the physical information of distributed loads as additional constraints within the end-to-end aerodynamic *** heterogenous data,a novel and easily applicable physical feature embedding modeling framework is *** framework extracts lowdimensional physical features from pressure distribution and then effectively enhances the modeling of the integrated loads via feature *** proposed framework can be coupled with multiple feature extraction methods,and the well-performed generalization capabilities over different airfoils are verified through a transonic *** with traditional direct modeling,the proposed framework can reduce testing errors by almost 50%.Given the same prediction accuracy,it can save more than half of the training ***,the visualization analysis has revealed a significant correlation between the discovered low-dimensional physical features and the heterogeneous aerodynamic loads,which shows the interpretability and credibility of the superior performance offered by the proposed deep learning framework.

关键词： Transonic flow Data-driven modeling Feature embedding Heterogenous data Feature visualization

Catalytically generated noncovalent ammonium dienolate:a versatile platform for the development of organocatalytic asymmetric cascade reactions

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Science China Chemistry 2024年第8期67卷 2524-2546页

作者： Jun-Bing Lin Dong-Sheng Ji peng-Fei xu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000China Shaanxi Key Laboratory of Chemical Reaction Engineering College of Chemistry and Chemical EngineeringYan’an UniversityYan’an 716000China

Organocatalytic cascade reactions represent a powerful strategy for the rapid construction of complex chiral molecules with multiple stereocenters from simple substrates under mild conditions. The intriguing structural feature and diverse reactivity of catalytically generated dienolate species render them competent and versatile intermediates for the development of practical and valuable cascade reactions. Over the past years, a plethora of innovative and pioneering noncovalent ammonium dienolatemediated cascade reactions have been designed and implemented under the catalysis of chiral organocatalysts, making dienolate activation a general, robust, and complementary method for the functionalization of unsaturated carbonyl compounds and related substances. This review illustrates the recent advances in organocatalytic noncovalent ammonium dienolate-mediated cascade reactions(mainly from 2010 to 2023), including the cascade transformations of ammonium dienolates directly generated from unsaturated ketone/aldehyde, ester/lactone/azlactone, amide/lactam/pyrazolone/oxindole, and alkylidene nitrile compounds. The contents are arranged based on the reaction types of the ammonium dienolates, with an emphasis on cascade 2,5-, 3,5-, and 4,5-difunctionalizations of these intermediates. Furthermore, other cascade reactions involving the 1,3-, 2,3-, and even more complex 3,4,5-reactivities of ammonium dienolates were also discussed. The reaction pathway, reaction stereoinduction, and synthetic applications of the ammonium dienolate-mediated cascade reactions were highlighted throughout the article. As a stimulating and ever-growing research area, the organocatalytic noncovalent ammonium dienolate-mediated cascade reactions are expected to continue demonstrating their magic power for constructing chiral targets in the future and further expanding the boundaries of asymmetric catalysis.

关键词： organocatalysis asymmetric catalysis ammonium dienolate cascade reaction difunctionalization

Multiple-quantum-coherence dynamics of spin-1 Bose–Einstein condensate during quantum phase transitions

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Communications in Theoretical Physics 2024年第1期76卷 105-110页

作者： Fulin Deng peng xu Su Yi Wenxian Zhang Key Laboratory of Artificial Micro-and Nano-structures of Ministry of Education School of Physics and TechnologyWuhan UniversityWuhanHubei 430072China School of Physics Zhengzhou UniversityZhengzhou 450001China CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China CAS Center for Excellence in Topological Quantum Computation&School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Wuhan Institute of Quantum Technology WuhanHubei 430206China

Multiple quantum coherences are often employed to describe quantum many-body dynamics in nuclear spin systems and recently,to characterize quantum phase transitions in trapped *** we investigate the multiple-quantum-coherence dynamics of a spin-1 Bose–Einstein *** adjusting the quadratic Zeeman shift,the condensate exhibits three quantum *** numerical results show that the spectrum of multiple quantum coherence does indeed catch the quantum critical *** importantly,with only a few low-order multiple quantum coherences,the spin-1 condensate exhibits rich signals of the many-body dynamics,beyond conventional *** experimental implementation of such multiple quantum coherence protocol is also discussed.

关键词： Bose-Einstein condensate spin-mixing dynamics quantum phase transitions multiple-quantum-coherences quantum entanglement

Effects of cooling rate on microstructure and microhardness of directionally solidified Galvalume alloy

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China Foundry 2024年第3期21卷 213-220页

作者： Ji-peng Li De-gao Qiao Jian Li Xiao-yang Luo peng peng Xian-tao Yan xu-dong Zhang Gansu Jiu Steel Group Hongxing Iron and Steel Co. Ltd.Jiayuguan 735111GansuChina School of Materials and Energy Lanzhou UniversityLanzhou 730000China

The influences of cooling rate on the phase constitution,microstructural length scale,and microhardness of directionally solidified Galvalume(Zn-55Al-1.6Si)alloy were investigated by directional solidification experiments at different withdrawal speeds(5,10,20,50,100,200,and 400μm·s^(-1)).The results show that the microstructure of directionally solidified Galvalume alloys is composed of primary Al dendrites,Si-rich phase and(Zn-Al-Si)ternary eutectics at the withdrawal speed ranging from 5 to 400μm·s^(-1).As the withdrawal speed increases,the segregation of Si element intensifies,resulting in an increase in the area fraction of the Si-rich *** addition,the primary Al dendrites show significant refinement with an increase in the withdrawal *** relationship between the primary dendrite arm spacing(λ_(1))and the thermal parameters of solidification is obtained:λ_(1)=127.3V^(-0.31).Moreover,as the withdrawal speed increases from 5 to 400μm·s^(-1),the microhardness of the alloy increases from 90 HV to 151 *** is a combined effect of grain refinement and second-phase strengthening.

关键词： Galvalume alloy directional solidification microstructure length scale microhardness

Effect of linear friction welding process on microstructure evolution,mechanical properties and corrosion behavior of GH4169 superalloy

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Chinese Journal of Aeronautics 2024年第6期37卷 504-520页

作者： Yu SU Xiawei YANG Tingxi MENG Dong WU Rui xu Haiyu xu Wenya LI Shuo yin State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Department of Mechanical Manufacturing&Biomedical EngineeringParsons BuildingTrinity College DublinThe University of DublinDublin 2Ireland

Linear Friction Welding(LFW)technology was used to realize the welding of GH4169 superalloy,and the effect of welding parameters on the microstructure,mechanical properties and corrosion behavior of the joint was *** results show that there is a positive correlation between the weld hardness and the tensile *** the gradual increase of heat input and welding pressure,the joint quality is gradually improved,but the heat affected zone is not significantly *** smaller the grain size of the weld,the higher the strength and plasticity of the *** the increase of the joint shortening amount,the corrosion resistance of the weld first gradually ***,when the shortening reaches a certain level,the corrosion resistance of the joint becomes little *** the increase of solution temperature,the corrosion current density increases and the polarization impedance *** higher the corrosion temperature,the worse the corrosion resistance of the *** is no significant correlation between the joint strength and the corrosion *** corrosion resistance of the joint can be enhanced without changing the joint mechanical properties by reducing the welding frequency and amplitude or increasing the welding pressure.

关键词： Linear Friction Welding(LFW) GH4169 superalloy Microstructure Mechanical properties Corrosion behavior

Spatial diversion and coordination of flood water for an urban flood control project in Suzhou, China

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Water Science and Engineering 2024年第2期17卷 108-117页

作者： Yu xu You-peng xu Qiang Wang Yue-feng Wang Chao Gao Department of Geography and Spatial Information Techniques Ningbo UniversityNingbo 315211China State Key Laboratoryof Hydology Water Resources and Hydraulic Enginering Nanjing Hydraulic Research InstitueNanjing 210029China Laboratory of Sustainable Urban Drainage Ningbo UniversityNingbo 31521lChina Schol of Gegraphical and Oceanographic Sciences Nanjing UniversiyNanjing 210023China School of Geography and Tourism Chongqing Normal UniversityChongqing 401331China

Suzhou City,located in the Yangtze River Delta in China,is prone to flooding due to a complex combination of natural factors,including its monsoon climate,low elevation,and tidally influenced position,as well as intensive human *** Large Encirclement Flood Control Project(LEFCP)was launched to cope with serious floods in the urban *** project changed the spatiotemporal pattern of flood processes and caused spatial diversion of floods from the urban area to the outskirts of the ***,this study developed a distributed flood simulation model in order to understand this transition of flood *** results revealed that the LEFCP effectively protected the urban areas from floods,but the present scheduling schemes resulted in the spatial diversion of floods to the outskirts of the *** rainstorm frequencies of 10.0%to 0.5%,the water level differences between two representative water level stations(Miduqiao(MDQ)and Fengqiao(FQ))located inside and outside the LEFCP area,ranged from 0.75 m to 0.24 m and from 1.80 m to 1.58 m,*** addition,the flood safety margin at MDQ and the duration with the water level exceeding the warning water level at FQ ranged from 0.95 m to 0.43 m and from 4 h to 22 h,*** scheduling schemes for the hydraulic facilities of the LEFCP in extreme precipitation cases were developed ac-cording to food simulations under seven scheduling *** helps to regulate the spatial flood diversion caused by the LEFCP during extreme precipitation.

关键词： Urban flooding Urban flood control project Rainstorm fregue ncy Flood simulation model Suzhou City

Generic and flexible self-correction method for nonlinearity-induced phase error in three-dimensional imaging

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Chinese Optics Letters 2024年第6期22卷 129-135页

作者： Jianhua Wang peng xu Yanxi Yang School of Information and Control Engineering Qingdao University of TechnologyQingdao 266520China School of Automation and Information Engineering Xi’an University of TechnologyXi’an 710048China

In three-dimensional imaging employing phase-shifting profilometry(PSP), the nonlinear response of projector and camera makes the fringe gray distribution non-sinusoidal, which further leads to phase error. Although the double 3-step phaseshifting method is simple and effective, it needs to add an additional set of fringe sequences, which reduces the measurement efficiency. To this end, this paper introduces a generic and flexible self-correction method for nonlinearity-induced phase ***, according to the nonlinearity-induced phase error model, we introduce an additional wrapped phase with a phase difference of π/3. The error waveform of the two wrapped phases is opposite but not coincident. Then, we introduce an estimation algorithm for the additional wrapped phase offset. Finally, we fuse the two wrapped phases to correct the phase error. Experiments confirm that the root mean squared error of the proposed method is 64.1% lower than that of the traditional method and 13.3% lower than that of the Hilbert transform method. The proposed method does not require any additional fringes or hardware assistance and can be easily extended to 4-step or 5-step PSP.

关键词： three-dimensional imaging phase-shifting profilometry nonlinear response self-correction Hilbert transform

Selective oxidation using in-situ generated hydrogen peroxide over titanosilicates

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结构化学 2024年第6期43卷 12-14页

作者： Zhipeng Wan Hao xu peng Wu State Key Laboratory of Petroleum Molecular & Process Engineering Shanghai Key Laboratory of Green Chemistry and Chemical ProcessesSchool of Chemistry and Molecular Engineering East China Normal UniversityShanghai200062China State Key Laboratory of Petroleum Molecular & Process Engineering Shanghai Key Laboratory of Green Chemistry and Chemical ProcessesSchool of Chemistry and Molecular Engineering East China Normal UniversityShanghai200062China Institute of Eco-Chongming Shanghai202162China

Titanosilicates are a class of heteroatom-containing zeolitic materials with tetrahedrally coordinated Ti4+ions incorporated into crystalline zeolite frameworks,with TS-1,Ti-MWW and Ti-MOR as representative and attractive selective oxidation *** liquid-phase oxidations of a variety of substrates such as olefins and ketones with the green oxidant of H2O2 over titanosilicates under mild conditions have attracted considerable research interests in the clean production of fine and bulk chemicals,among which propylene epoxidation and cyclohexanone ammoximation have been industrialized[1].

关键词： PHASE EPOXIDATION PROPYLENE H-2

A novel strategy of tannery sludge disposal–converting into biochar and reusing for Cr(Ⅵ)removal from tannery wastewater

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Journal of Environmental Sciences 2024年第4期138卷 637-649页

作者： Zhiwei Li Di Yu Xingdong Wang xuejiao Liu Zhen xu yin Wang CAS Key Laboratory of Urban Pollutant Conversion Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China University of Chinese Academy of Sciences Beijing 100049China Zhejiang Key Laboratory of Urban Environmental Processes and Pollution Control CAS Haixi Industrial Technology Innovation Center in BeilunNingbo 315830China Key Laboratory of Urban Environment and Health Ningbo Observatio

Tannery sludge with high chromium content has been identified as hazardous solid waste due to its potential toxic *** safety disposal and valorization of the tannery sludge remains a *** this study,the chromium stabilization mechanism was systematically investigated during chromium-rich tannery sludge was converted to biochar and the removal performance of the sludge biochar(SBC)for Cr(Ⅵ)from tannery wastewater was also *** results showed that increase in pyrolysis temperature was conductive to the stabilization of Cr and significant reduction of the proportion of Cr(Ⅵ)in *** was confirmed that the stabilization of chromium mainly was attributed to the embedding of chromium in the C matrix and the transformation of the chromium-containing substances from the amorphous Cr(OH)_(3)to the crystalline state,such as(FeMg)Cr_(2)O_(5).The biochar presented high adsorption capacity of Cr(Ⅵ)at low pH and the maximal theoretical adsorption capacity of SBC produced at 800°C can reach 352 mg Cr(Ⅵ)/g,the process of which can be well expressed by Langmuir adsorption isotherm and pseudo second order *** electrostatic effect and reduction reaction were dominantly responsible for the Cr(Ⅵ)adsorption by ***,this study provided a novel strategy for the harmless disposal and resource utilization for the solid waste containing chromium in leather industry.

关键词： Chromium-rich tannery sludge Pyrolysis Biochar Stabilizationmechanisms Cr(Ⅵ)adsorption