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Changes in Summer Persistent Precipitation over the Middle–Lower Reaches of the Yangtze River and Associated Atmospheric Circulation Patterns

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Journal of Meteorological Research 2021年第3期35卷 393-401页

作者： rong yu Panmao ZHAI State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesChina Meteorological AdministrationBeijing 100081

Persistence is an important property of precipitation and its related impacts. However, changes in persistent precipitation and the possible underlying mechanisms in the context of global warming have not yet been discussed in sufficient depth. In this study, the changes in persistent precipitation in summer and related atmospheric circulation patterns over the middle–lower reaches of the Yangtze River(MLRYZR)—a typical monsoon region frequently hit by consecutive rainfall events—are analyzed based on observed daily precipitation and NCEP/NCAR reanalysis data from 1961 to 2019. The results reveal that persistent precipitation events(PPs) tend to happen in a more persistent way, with increased frequency and intensity in the MLRYZR region. Mechanism analyses show that persistent precipitation has happened along with simultaneous enhancement of some large-scale atmospheric circulation patterns,including the Lake Baikal blocking(BB), the Okhotsk Sea blocking(OB), and the western Pacific subtropical high(WPSH). Such enhanced anomalous circulation patterns could persistently reinforce the convergence and supply of water vapor in the MLRYZR region, contributing to the increase in PPs in this region. Based on the above results, we are able to offer some new insights into the long-term changes in precipitation structure and the possible causes. This study is also expected to support attribution studies on regional precipitation changes in the future.

关键词： persistent precipitation precipitation change atmospheric circulation pattern

Dynamical signatures of the one-dimensional deconfined quantum critical point

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Chinese Physics B 2022年第5期31卷 73-82页

作者： Ning Xi rong yu Department of Physics and Beijing Key Laboratory of Opto-electronic Functional Materials and Micro-nano Devices Renmin University of ChinaBeijing 100872China

We study the critical scaling and dynamical signatures of fractionalized excitations at two different deconfined quantum critical points(DQCPs)in an S=1/2 spin chain using the time evolution of infinite matrix product *** scaling of the correlation functions and the dispersion of the conserved current correlations explicitly show the emergence of enhanced continuous symmetries at these *** dynamical structure factors in several different channels reveal the development of deconfined fractionalized excitations at the ***,we find an effective spin-charge separation at the DQCP between the ferromagnetic(FM)and valence bond solid(VBS)phases,and identify two continua associated with different types of fractionalized excitations at the DQCP between the X-direction and Z-direction FM *** findings not only provide direct evidence for the DQCP in one dimension but also shed light on exploring the DQCP in higher dimensions.

关键词： one-dimensional antiferromagnetism spin frustration deconfined quantum critical point spin dynamics infinite time-evolving block decimation

Interpretable Tourism Demand Forecasting with Two-Stage Decomposition and Temporal Fusion Transformers

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Journal of Systems Science & Complexity 2024年第6期37卷 2654-2679页

作者： WU Binrong WANG Lin ZENG yu-rong Business School Hohai UniversityNanjing 211100China School of Management Huazhong University of Science and TechnologyWuhan 430074China School of Information Engineering Hubei University of EconomicsWuhan 430205China

This paper proposes a novel interpretable tourism demand forecasting framework that considers the impact of the COVID-19 pandemic by using multi-source heterogeneous data,namely,historical tourism volume,newly confirmed cases in tourist origins and destinations,and search engine *** paper introduces newly confirmed cases in tourist origins and tourist destinations to forecast tourism demand and proposes a new two-stage decomposition method called ensemble empirical mode decomposition-variational mode decomposition to deal with the tourist arrival *** solve the problem of insufficient interpretability of existing tourism demand forecasting,this paper also proposes a novel interpretable tourism demand forecasting model called JADE-TFT,which utilizes an adaptive differential evolution algorithm with external archiving(JADE)to intelligently and efficiently optimize the hyperparameters of temporal fusion transformers(TFT).The validity of the proposed prediction framework is verified by actual cases based on Hainan and Macao tourism data *** interpretable experimental results show that newly confirmed cases in tourist origins and tourist destinations can better reflect tourists'concerns about travel in the post-pandemic era,and the two-stage decomposition method can effectively identify the inflection point of tourism prediction,thereby increasing the prediction accuracy of tourism demand.

关键词： COVID-19 interpretable deep learning search engine data tourism demand forecasting

Oxygen adatoms and vacancies on the (110) surface of CeO2

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Science China(Technological Sciences) 2018年第1期61卷 135-139页

作者： HUANG JingLu yu yunBo ZHU Jing yu rong National Center for Electron Microscopy in Beijing Key Laboratory of Advanced Materials of Ministry of Education of China State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and Engineering Tsinghua University Beijing 100084 China State Key Joint Laboratory of Environment Simulation and Pollution Control Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Center for Excellence in Regional Atmospheric Environment Institute of Urban Environment Chinese Academy of Sciences Xiamen 361021 China University of Chinese Academy of Sciences Beijing 100049 China

The behavior of oxygen on ceria surfaces is closely related with the applications of ceria as a catalyst and oxygen conductor in solid-oxide fuel cells. Here, the atomic configurations of oxygen adatoms and vacancies on the(110) surface of CeO_2 have been studied combining aberration-corrected transmission electron microscopy and first-principles calculations. The oxygen adatoms were estimated to be located on top of Ce atoms with 50% coverage, forming a c(2×2) reconstruction. The oxygen vacancies can form stable configuration, with the Ce atoms partly reduced.

关键词： surface structure ceria oxygen adatoms oxygen vacancies aberration-corrected TEM first-principles calculations

Zn-Fe and Y-modified Zn-Fe coatings on 42CrMo steel via pack cementation

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Rare Metals 2021年第8期40卷 2266-2274页

作者： Li Liu Si-rong yu Wen-An Cao School of Materials Science and Engineering China University of Petroleum(East China)Qingdao266580China

Zn-Fe and Y-modified Zn-Fe coatings were prepared on 42 CrMo steel through pack cementation processes at 370,390 and 410℃ for 4 h.Y modification was achieved through the co-deposition of Zn and Y_(2)O_(3).The effects of Y modification on microstructure,formation and corrosion behavior of the Zn-Fe coating were *** coating thickness increased with an increase in *** Y-modified Zn-Fe coating was thicker than the plain Zn-Fe *** the Zn-Fe coating and Y-modified Zn-Fe coating showed single-layered structures,but the overall microstructure was improved by Y *** activation energies for Zn-Fe coating and Y-modified Zn-Fe coating were 113.15 and80.65 kJ·mol^(-1),*** Zn-Fe coating consisted of FeZn_(13) and Fe11Zn40 *** effects of Y modification on the corrosion behavior of the Zn-Fe coating were evaluated through an immersion test and polarization *** results showed that the corrosion resistance was improved by Y modification.

关键词： Pack cementation Coating Modification Activation energy Corrosion

Global phase diagram of a spin–orbit-coupled Kondo lattice model on the honeycomb lattice

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Chinese Physics B 2019年第7期28卷 413-420页

作者： Xin Li rong yu Beijing National Laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of Sciences Beijing 100190 China School of Physical Sciences University of Chinese Academy of Sciences Beijing 100049 China Department of Physics and Beijing Key Laboratory of Opto-electronic Functional Materials and Micro-nano Devices Renmin University of China Beijing 100872 China Department of Physics & Astronomy Rice Center for Quantum Materials Rice University Houston Texas 77005 USA

Motivated by the growing interest in the novel quantum phases in materials with strong electron correlations and spin–orbit coupling, we study the interplay among the spin–orbit coupling, Kondo interaction, and magnetic frustration of a Kondo lattice model on a two-dimensional honeycomb *** calculate the renormalized electronic structure and correlation functions at the saddle point based on a fermionic representation of the spin *** find a global phase diagram of the model at half-filling, which contains a variety of phases due to the competing *** addition to a Kondo insulator, there is a topological insulator with valence bond solid correlations in the spin sector, and two antiferromagnetic *** to the competition between the spin–orbit coupling and Kondo interaction, the direction of the magnetic moments in the antiferromagnetic phases can be either within or perpendicular to the lattice *** latter antiferromagnetic state is topologically nontrivial for moderate and strong spin–orbit couplings.

关键词： heavy fermion system Kondo insulator spin–orbit coupling

Stabilization of Sb nanoparticles using metal–organic frameworks to obtain stable performance of anode material for sodium-ion batteries

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Rare Metals 2022年第5期41卷 1406-1409页

作者： Kang Liang yu-rong Ren School of Materials Science and Engineering Jiangsu Province Engineering Research Center of Intelligent Manufacturing Technology for the New Energy Vehicle Power BatteryChangzhou UniversityChangzhou 213164China

Sodium-ion batteries(SIBs)have received much attention as a potential energy storage system to replace lithium-ion batteries(LIBs)due to the abundant sodium resources and low cost[1,2].Recently,conversion materials[3]... 详细信息

关键词： replace insertion lithium

Role of the spin anisotropy of the interchain interaction in weakly coupled antiferromagnetic Heisenberg chains

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Chinese Physics B 2020年第5期29卷 489-493页

作者： yuchen Fan rong yu Department of Physics and Beijing Key Laboratory of Opto-electronic Functional Materials and Micro-nano Devices Renmin University of ChinaBeijing 100872China

In quasi-one-dimensional(q1D) quantum antiferromagnets, the complicated interplay of intrachain and interchain exchange couplings may give rise to rich phenomena. Motivated by recent progress on field-induced phase transitions in the q1D antiferromagnetic(AFM) compound YbAlO3, we study the phase diagram of spin-1/2 Heisenberg chains with Ising anisotropic interchain couplings under a longitudinal magnetic field via large-scale quantum Monte Carlo simulations,and investigate the role of the spin anisotropy of the interchain coupling on the ground state of the system. We find that the Ising anisotropy of the interchain coupling can significantly enhance the longitudinal spin correlations and drive the system to an incommensurate AFM phase at intermediate magnetic fields, which is understood as a longitudinal spin density wave(LSDW). With increasing field, the ground state changes to a canted AFM order with transverse spin correlations. We further provide a global phase diagram showing how the competition between the LSDW and the canted AFM states is tuned by the Ising anisotropy of the interchain coupling.

关键词： quasi-one-dimensional quantum antiferromagnets Heisenberg spin chain longitudinal spin density wave

Treatment of coke plant wastewater by SND fixed biofilm hybrid system

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Journal of Environmental Sciences 2007年第2期19卷 153-159页

作者： QI rong YANG Kun yu Zhao-xiang Department of Chemistry Tongji University Shanghai 200092 China

In this article, coke plant wastewater was treated by a simultaneous nitrifying and denitrifying （SND） fixed biofilm hybrid system. The results showed that suitable parameters of the system were important for the performance of the bio-degradation system. The chemical oxygen demand （COD） removal efficiency in this system was satisfactory, higher than 94%, and ammonia nitrogen was higher than 95%. The effluent COD concentration could meet the discharge standard, except for very few situations. The results showed that a sufficient carbon source was important for making ammonia nitrogen concentration meet the discharge standard. Then the TiN removal efficiency in this system can be brought higher than 94%. Dissolved oxygen （DO） is very important to the performance of the SND bio-degradation system, and the suitable DO is about 3.5-4.0 mg/L at the forepart of reactor. In addition, the performance of the system was almost not affected by pH value. The results show that the system is feasible to treat coke plant wastewater.

关键词： coke plant wastewater SND fixed biofilm ammonia nitrogen COD carbon source