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Moments of inertia of triaxial nuclei in covariant density functional theory

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Nuclear Science and Techniques 2024年第10期35卷 197-207页

作者： yu-meng Wang Qi-Bo Chen Department of Physics East China Normal UniversityShanghai 200241China

The covariant density functional theory(CDFT)and five-dimensional collective Hamiltonian(5DCH)are used to analyze the experimental deformation parameters and moments of inertia(MoIs)of 12 triaxial nuclei as extracted by Allmond and Wood[*** and ***,***.B 767,226(2017)].We find that the CDFT MoIs are generally smaller than the experimental values but exhibit qualitative consistency with the irrotational flow and experimental data for the relative MoIs,indicating that the intermediate axis exhibites the largest ***,it is found that the pairing interaction collapse could result in nuclei behaving as a rigid-body flow,as exhibited in the^(186-192)Os ***,by incorporating enhanced CDFT MoIs(factor of f≈1.55)into the 5DCH,the experimental low-lying energy spectra and deformation parameters are reproduced *** with both CDFT and the triaxial rotor model,the 5DCH demonstrates superior agreement with the experimental deformation parameters and low-lying energy spectra,respectively,emphasizing the importance of considering shape fluctuations.

关键词： Moment of inertia Trixial nucleus Covariant density functional theory Five-dimensional collective Hamiltonian Low-lying energy spectrum

Adsorption of Dyes Using Multi-walled Carbon Nanotube Hydrogel

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Chemical Research in Chinese Universities 2019年第2期35卷 311-318页

作者： yu meng LIU Miao College of New Energy and Environment Jilin UniversityChangchun 130012P.R.China

The hydrophilic multi-walled carbon nanotube(MWCNT)hydrogel was prepared using acrylic acid,acrylamide and hydrophilic *** orthogonal experiment was applied to optimize the synthetic *** MWCNT hydrogel was characterized by Fourier transform infrared spectrophotometer(FTIR)and scanning electron microscopy(SEM)*** MWCNT hydrogel was used as the adsorbent to adsorb water-soluble cationic *** study evaluated the adsorption performance of hydrogels on four dyes of safranine Ts crystal violet,malachite green and methylene blue in *** effects of the amount of hydrogel,the size of hydrogel,pH;and the temperature on the adsorption performance were *** adsorption kinetic and adsorption isotherm curves were *** experimental results show that the MWCNT hydrogel can be easily separated from water and the adsorption capacity is much greater compared to the hydrogel without *** MWCNT hydrogels can be used in wastewater treatment with a great potential.

关键词： Multi-walled carbon nanotube Poly(acrylamide/acrylic acid) Hydrogel Dye Adsorption

Shortest Link Scheduling in Wireless Networks with Oblivious Power Control

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China Communications 2021年第4期18卷 137-152页

作者： Chunmei Ma Jiguo yu Baogui Huang yu meng School of Computer Science Qufu Normal UniversityRizhao 276826China School of Computer Science and Technology Qilu University of Technology(Shandong Academy of Sciences)Jinan 250353China Shandong Computer Science Center(National Supercomputer Center in Jinan) Jinan 250014China Shandong Provincial Key Laboratory of Computer Networks Jinan 250014China School of Computer Science&Technology Georgia State UniversityGA 30303USA

Link scheduling has always been a fundamental problem in wireless networks for its direct impacts on the performance of wireless networks such as throughput capacity,transmission delay,lifetime,*** work is mainly established under graphbased models,which are not only impractical but also incorrect due to the essentially fading characteristics of *** this paper,we study the shortest link scheduling problem under two more realistic models,namely the signal to interference plus noise ratio(SINR)model and the Rayleigh fading *** propose a centralized square-based scheduling algorithm(CSSA)with oblivious power control under the SINR model and prove its correctness under both the SINR model and the Rayleigh fading ***,we extend CSSA and propose a distributed square-based scheduling algorithm(DSSA).Note that DSSA adopts CSMA/CA so that a wireless node can compete for the wireless channel before starting its *** also show theoretical analysis and conduct extensive simulations to exhibit the correctness and efficiency of our algorithms.

关键词： link scheduling SINR Rayleigh fading wireless networks wireless communications

Family Policy and Gender-role Attitudes in East Asia:A Comparative Analysis of Japan,South Korea and China

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学术界 2017年第12期 257-270页

作者： yu meng Sungkyunkwan University

This study explored the continuum of traditional gender relations embedded in the welfare practices of three countries with the help of the concept"gender contract"about the facilitate female participation in paid employment( the"official contracts)are reflected in gender role attitudes( the"normative"contracts) and behavior in family( the"everyday"contracts). In East Asian including Japan,South Korea and China,policymakers need to work further to encourage dual care,and also to strengthen the responsibility of the state in childcare. Especially in China,the implementation of the policy of two children to make more and more women bear more rearing pressure. In the absence of public parenting policies,women may be forced to withdraw from the labor market, childcare will also be a important social problem. Chinese government needs to deal with this problem as soon as possible.

关键词： family policy gender-role attitudes male breadwinner model Japan South Korea China

High-fidelity numerical simulation of unsteady cavitating flow around a hydrofoil

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Journal of Hydrodynamics 2023年第1期35卷 1-16页

作者： Nan Xie yu-meng Tang Yang-wei Liu School of Energy and Power Engineering Beihang UniversityBeijing100191China National Key Laboratory of Science and Technology on Aero-Engine Aero-Thermodynamics Beihang UniversityBeijing100191China

Cavitation is a widespread and detrimental phenomenon in hydraulic machinery, therefore, it requires to be accurately predicted. In this study, large eddy simulation (LES), scale-adaptive simulation (SAS) and grid-adaptive simulation (GAS) are employed to investigate the unsteady cavitating flow around a NACA0009 hydrofoil. The prediction accuracy of GAS, SAS, both using the shear-stress transport (SST) k — ω model as baseline turbulence model, is validated by comparing with experimental and LES results. The cavity behaviors and turbulence fields are analyzed systematically. Results show that the GAS gives a more reasonable turbulent viscosity and accurately predicts the periodic evolution of typical vortical structures of cavitating flow, such as tip leakage vortex cavitation, tip separation vortex cavitation, leading-edge cavitation, and trailing-edge vortex. The time-averaged cavity volume, volume fluctuation amplitude, and characteristic frequencies of cavities predicted by the GAS are very closed to the LES, while the SAS fails to accurately capture these cavity characteristics. Furthermore, the local trace criterion is applied to extract the vortical structures and to analyze the swirling patterns of the tip leakage vortex. Multi-scale vortical structures in LES are well identified by local trace criterion. The prediction accuracy of the SAS method for small-scale vortical structures, such as the vortex shedding on the suction side and the vortex rope around the tip leakage vortex, is obviously insufficient, while the GAS has a higher accuracy in predicting vortex shedding. The tip leakage vortex and induced vortex extracted from GAS are also closer to that of LES in both swirling patterns and scale.

关键词： Tip leakage vortex cavitation leading-edge cavitation large eddy simulation(LES) grid-adaptive simulation scale-adaptive simulation

A 3-D morphological approach on spatial form and cultural identity of ethnic mountain settlements:Case from Guizhou,China

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Journal of Mountain Science 2021年第5期18卷 1144-1158页

作者： JIA Zi-yu meng Cheng-yu ZHOU Zheng-xu School of Architecture Tsinghua UniversityBeijing 100084China China National Engineering Research Center for Human Settlement China Architecture Design and Research GroupBeijing 100044China School of Landscape Architecture Beijing Forestry UniversityBeijing 100083China

Ethnic mountain settlements are living heritage of varied vernacular *** preservation of both the built form and the intangible socio-cultural associations with them are global concern in process of urbanization,and in the notion of sustainable ***,there is a lack of multi-dimensional and cross-cultural quantitative research in settlement morphology,making it difficult to guide practice ***,this study focuses on exploring an automatic or semi-automatic quantification and classification method for the morphological identity of ethnic mountain *** introduce and combine 3-D morphological indicators with existing 2-D indicators to build and test three different sets of indication systems for semi-automatic classification for the settlements’ethnic attribute basing on spatial *** the Miao,Dong,and Tunpu(Han)ethnic settlements in Guizhou province,southwest China as research samples,we applied factor analysis and hierarchical clustering methods to compare the classification accuracy under the three systems using data from topographic map,field investigation map,satellite imageries,and ethnography or local *** results showed that,the 3-D indication system has succeeded in semi-automatic quantification and classification of settlement morphology and ethnic identity by greatly increasing the classification accuracy to 96.30%,which is a huge improvement compared with the basic 2-D indication system(42.59%)and the advanced 2-D indication system(61.11%).The settlement samples are further divided into two sub-types with significant morphological differences in each major ethnic category under the 3-D indication *** then discussed the potential improvement and future large-scale application of this method with the help of machine learning and other smart *** hope to provide a comprehensive quantitative perspective and a more scientific reference for the future preservation and sustainable

关键词： 3-D morphology Quantitation Ethnic mountain settlements Cultural identity China

Diastereodivergent Hydrosilylative Enyne Cyclization Catalyzed by N-Heterocyclic Carbene-Ni(o)

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Chinese Journal of Chemistry 2021年第6期39卷 1587-1592页

作者： meng yu Xuefeng Yong Weiwei Gao Chun-yu Ho Guangdong Province Key Laboratory of Catalysis Department of ChemistrySouthern University of Science and Technology(SUSTech)1088 Xueyuon AvenueShenzhenGuangdong 518055China Shenzhen Grubbs Institute Deportment of ChemistrySouthern University of Science and Technology(SUSTech)1088 Xueyuan AvenueShenzhenGuangdong 518055China

Catalytic diastereodivergent hydrosilylative enyne cyclization with high generality and broad scope was achieved using electronic ac-tivated N-heterocyclic carbene-Ni(O)as a catalyst and R_(3)SiH as silane(IPr^(Cl),syn-:anti-selectivity from up to 98:2 to 7:93 by Z=0,NH ***,R^(1)=n-pentyl).Heterocycles bearing homoallylsilane rather than vinylsilane was obtained *** undesired yet highly competitive reactivity was suppressed,like direct hydrosilylation of alkene and alkyne ***,the homoallylsilane products could be reduced further in one-pot using IPr^(Me) as ligand and(EtO)_(3)SiH as silane under otherwise the same standard condition as the above,offering practical access to additional stereocenters and more diverse product structures from enynes.

关键词： N-Heterocyclic carbenes Enynes Diastereodivergent synthesis Hydrosilylation Hydroalkenylation

Energy Saving for Automatic Train Control in Moving Block Signaling System

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China Communications 2014年第A2期11卷 12-22页

作者： GU Qing meng yu MA Fei School of Mechanical Engineering University of Science and Technology Beijing Beijing 100083 E R. China

With rapid development of the railway traffic, the moving block signaling system （MBS） method has become more and more important for increasing the track capacity by allowing trains to run in a shorter time-headway while maintaining the required safety margins. In this framework, the tracking target point of the following train is moving forward with its leading train. This paper focuses on the energy saving tracking control of two successive trains in MBS. Nonlinear programming method is used to optimize the energy-saving speed trajectory of the following train. The real-time location of the leading train could be integrated into the optimization process. Due to simplicity, it can be used for online implementation. The feasibility and effectiveness are verified through simulation. The results show that the new method is efficient on energy saving even when disturbances present.

关键词： moving block signaling (MBS) energy saving automatic train protection (ATP) automatic train operation (ATO) tracking train speed trajectory

Acoustic emission detection of 316L stainless steel welded joints during intergranular corrosion

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International Journal of Minerals,Metallurgy and Materials 2015年第9期22卷 942-949页

作者： meng-yu Chai Quan Duan Wen-jie Bai Zao-xiao Zhang Xu-meng Xie School of Chemical Engineering and Technology Xi'an Jiaotong University Zhejiang Provincial Special Equipment Inspection Institute

This study analyzes acoustic emission （AE） signals during the intergranular corrosion （IGC） process of 316L stainless steel welded joints under different welding currents in boiling nitric acid. IGC generates several AE signals with high AE activity. The AE technique could hardly distinguish IGC in stainless steel welded joints with different welding heat inputs. However, AE signals can effectively distinguish IGC characteristics in different corrosion stages. The IGC resistance of a heat-affected zone is lower than that of a weld zone. The initiation and rapid corrosion stages can be distinguished using AE results and microstructural analysis. Moreover, energy count rate and amplitude are considered to be ideal parameters for characterizing different IGC processes. Two types of signals are detected in the rapid corrosion stage. It can be concluded that grain boundary corrosion and grain separation are the AE sources of type 1 and type 2, respectively.

关键词： stainless steel intergranular corrosion acoustic emission microstructure weight loss