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Interdecadal Change in the Interannual Variation of the Western Edge of the Western North Pacific Subtropical High During Early Summer and the Influence of Tropical Sea Surface Temperature

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Journal of Tropical Meteorology 2022年第1期28卷 57-70页

作者： ZHAN Hong-yu chen rui-dan LAN Ming Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies/School of Atmospheric Sciences Sun Yat-sen University and Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)ZhuhaiGuangdong 519082 China School of Marine Sciences Sun Yat-sen UniversityZhuhaiGuangdong 519082 China

This study reveals that the interannual variability of the western edge of the western North Pacific(WNP)subtropical high(WNPSH)in early summer experienced an interdecadal decrease around ***,the zonal movement of the WNPSH and the zonal extension of the high-pressure anomaly over the WNP(WNPHA)in abnormal years possess smaller ranges after *** different influences of the tropical SSTAs are important for this interdecadal change,which exhibit slow El Nino decaying pattern before 1990 while rapid transformation from El Nino to La Nina after *** early summer tropical SSTAs and the relevant atmospheric circulation anomalies present obvious interdecadal *** 1990,the warm SSTAs over the northern Indian Ocean and southern South China Sea favor the WNPHA through eastward-propagating Kelvin wave and meridional-vertical circulation,***,the warm SSTA over the tropical central Pacific induces anomalous ascent to its northwest through the Gill response,which could strengthen the anomalous descent over the WNP through meridional-vertical circulation and further favor the eastward extension of the WNPHA to central *** 1990,the warm SSTAs over the Maritime Continent and northern Indian Ocean cause the WNPHA through meridional-vertical and zonal-vertical circulation,***,the anomalous warm SSTs and ascent and the resultant anomalous descent over the WNP are located more westward and southward after 1990 than before ***,the WNPHA features narrower zonal range and less eastward extension after 1990,corresponding to the interdecadal decease in the interannual variability of the western edge of the *** the other hand,the dominant oscillation period of ENSO experienced an interdecadal reduction around 1990,contributing to the change of the El Nino SSTA associated with the anomalous WNPSH from slow decaying type to rapid transformation type.

关键词： western North Pacific subtropical high interdecadal change interannual variation tropical sea surface temperature ENSO

6个朱砂梅品种花色苷合成结构基因及转录因子编码基因的表达模式分析

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江苏农业学报 2024年第2期40卷 367-375页

作者：郭梦鸽秦孝天陈瑞丹北京林业大学园林学院北京100083 花卉种质创新与分子育种北京市重点实验室北京100083 国家花卉工程技术研究中心北京100083 城乡生态环境北京实验室北京100083 园林环境教育部工程研究中心北京100083 林木花卉遗传育种教育部重点实验室北京100083

为明晰朱砂梅品种群梅花花色表型差异形成的分子调控机制,以花色由浅至深呈梯度变化的6个朱砂梅品种为试验材料,利用色差仪和分光光度计测定不同品种盛花期花瓣的花色表型及花色苷含量,通过荧光定量PCR及相关性分析,对花色苷合成结构基... 详细信息

为明晰朱砂梅品种群梅花花色表型差异形成的分子调控机制,以花色由浅至深呈梯度变化的6个朱砂梅品种为试验材料,利用色差仪和分光光度计测定不同品种盛花期花瓣的花色表型及花色苷含量,通过荧光定量PCR及相关性分析,对花色苷合成结构基因(PmCHS、PmCHI、PmF3H、PmF3′H、PmDFR、PmANS、PmUFGT)及转录因子编码基因(PmMYB1、PmbHLH3)的转录特性进行探究。结果表明,各品种间花瓣花色苷含量与花色红度的变化趋势一致;PmMYB1、PmbHLH3、PmF3′H、PmDFR、PmUFGT的相对表达量与花色苷含量呈极显著正相关;转录因子编码基因PmMYB1与PmbHLH3的相对表达量呈极显著正相关,且均与结构基因PmF3′H、PmDFR、PmUFGT的表达水平呈显著或极显著正相关。推测转录因子编码基因PmMYB1PmbHLH3通过正向调控结构基因PmF3′H、PmDFR和PmUFGT的表达从而调控朱砂梅花瓣的呈色。

关键词：梅花花色苷结构基因转录因子荧光定量PCR

In situ modification of heavy oil catalyzed by nanosized metal-organic framework at mild temperature and its mechanism

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Chinese Journal of Chemical Engineering 2024年第3期67卷 166-173页

作者： Li Wang Ji-Xiang Guo rui-Ying Xiong chen-Hao Gao Xiao-Jun Zhang dan Luo The Unconventional Oil and Gas Institute China University of Petroleum-BeijingBeijing 102200China Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of SciencesBeijing 101400China

Two catalysts, nano-sized cobalt-metal-organic framework(Co-MOF) and nickel(Ni)-MOF, were successfully prepared by the modification method. Tetralin(C10H12) was used as the hydrogen donor for the catalytic cracking and hydrogenation modification study of the dehydrated crude oil from the Shengli Oilfield. The optimal reaction conditions were determined through orthogonal experiments, and the components of the crude oil and modified oil samples were analyzed. The results revealed that the nanoMOF catalysts were successfully prepared and exhibited high catalytic activity. They could catalyze the cracking of large molecules in heavy oil at mild temperatures(<300°C), leading to the decomposition of the hydrogen donor. When the mass fraction of the catalyst was 0.2%, the mass fraction of the hydrogen donor was 1%, and the reaction temperature was 280°C, the Ni-MOF showed the best catalytic viscosity reduction effect. It could reduce the viscosity of heavy oil at 50°C from 15761.9 m Pa.s to 1266.2 m Pa.s,with a viscosity reduction rate of 91.97%. The modification effect of Co-MOF was the next best, which could reduce the viscosity of heavy oil to 2500.1 m Pa.s with a viscosity reduction rate of 84.14%. Molecular dynamics simulations revealed a strong interaction force between the MOF surface and asphaltene molecules. In the process of heavy-oil catalytic hydrogenation, the nano-MOF catalyst exhibited high catalytic activity. On the one hand, the empty d orbitals outside the metal atoms in the catalyst could polarize the carbon atoms in the organic matter, accelerating the breaking of long chains. On the other hand, the metal atoms in the catalyst could bond with the carbon σ bonds, breaking the carbon-carbon bonds. This disrupted the structure of the recombined components in the crude oil, irreversibly reducing the viscosity of the heavy oil and improving its fluidity.

关键词： Nano-sized MOF Petroleum Viscosity reduction Catalyst Nanomaterials

A southward withdrawal of the northern edge of the East Asian summer monsoon around the early1990s

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Atmospheric and Oceanic Science Letters 2018年第2期11卷 136-142页

作者： ZHU Xiao-Cui GUO Yuan-Yuan ZHANG Hai-Yan LI Xiu-Zhen chen rui-dan WEN Zhi-Ping Center for Monsoon and Environment Research School of Atmospheric Sciences Sun Yat-sen University Guangzhou China South China Sea Marine Forecasting Center of State Oceanic Administration Guangzhou China Jiangsu Collaborative Innovation Center for Climate Change Guangzhou China lnstitute of Atmospheric Sciences Fudan University Shanghai China

The northern edge of the East Asian summer monsoon （EASM） is identified using the pentad total column water vapor obtained from ERA-Interim reanalysis data during *** orthogonal function analysis is applied to study the meridional displacement of the northern edge of the EASM during the study period,and the results show an interdecadal southward shift around 1993/1994 and an indistinct northward displacement after 2007/*** focus on the interdecadal change around 1993/1994,composite analysis using the difference between 1979-1993 and 1994-2007 is *** examination of the differences between these two periods,a significant anticyclonic anomaly is found over Mongolia,suggesting a pronounced interdecadal weakening of the Mongolian low during ***,northward advancement of the EASM may have been prevented by the anomalous northerly flow to the east of the weakened Mongolian low after *** study shows that the interdecadal weakening of the Mongolian low might be attributable to the meridional inhomogeneity of surface warming over the northern part of East *** studies suggest that such meridional inhomogeneity would lead to a reduction in local atmospheric baroclinicity,and thus the suppression of extratropical cyclone activity over Mongolia,resulting in a southward withdrawal of the northern edge of the EASM on the interdecadal timescale.

关键词： East Asian summer monsooninterdecadal change Mongolian extratropicalcyclone Mongolian low surface warming

On the half-quantized Hall conductance of massive surface electrons in magnetic topological insulator films

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 127-136页

作者： rui chen Shun-Qing Shen Department of Physics The University of Hong KongHong Kong 999077China Department of Physics Hubei UniversityWuhan 430062China

In topological insulators,massive surface states resulting from local symmetry breaking were thought to exhibit a half-quantized Hall conductance,obtained from the low-energy effective model in an infinite Brillouin *** a lattice model,the surface band is composed of a combination of surface states and bulk *** massive surface states alone may not be enough to support an exact one-half quantized surface Hall conductance in a finite Brillouin zone and the whole surface band always gives an integer quantized Hall conductance as enforced by the TKNN *** explore this,we investigate the band structures of a lattice model describing the magnetic topological insulator film that supports the axion insulator,Chern insulator,and semi-magnetic topological insulator *** reveal that the gapped and gapless surface bands in the three phases are characterized by an integer-quantized Hall conductance and a half-quantized Hall conductance,*** propose an effective model to describe the three phases and show that the low-energy dispersion of the surface bands inherits from the surface Dirac *** gapped surface band manifests a nearly half-quantized Hall conductance at low energy near the center of Brillouin zone,but is compensated by another nearly half-quantized Hall conductance at high energy near the boundary of Brillouin zone because a single band can only have an integer-quantized Hall *** gapless band hosts a zero Hall conductance at low energy but is compensated by another half-quantized Hall conductance at high energy,and thus the half-quantized Hall conductance can only originate from the gapless ***,we calculate the layer-resolved Hall conductance of the *** conclusion suggests that the individual gapped surface band alone does not support the half-quantized surface Hall effect in a lattice model.

关键词： magnetic topological insulator Dirac equation half-quantized Hall conductance

Polysulfide regulation by defect-modulated Ta_(3)N_(5-x) electrocatalyst toward superior room-temperature sodium-sulfur batteries

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Science Bulletin 2024年第2期69卷 197-208页

作者： Zhen Zhang dan Luo Jun chen Chuyin Ma Matthew Li Haoze Zhang Renfei Feng rui Gao Haozhen Dou Aiping Yu Xin Wang Zhongwei chen Department of Chemical Engineering Waterloo Institute for NanotechnologyUniversity of WaterlooWaterloo N2L 3G1Canada Dalian Institute of Chemical Physics Chinese Academy of SciencesDalian 116023China South China Academy of Advanced Optoelectronics&International Academy of Optoelectronics at Zhaoqing South China Normal UniversityGuangzhou 510006China Chemical Sciences and Engineering Division Argonne National LaboratoryLemont 60439USA Canadian Light Source Saskatoon S7N 2V3Canada

Resolving low sulfur reaction activity and severe polysulfide dissolution remains challenging in metalsulfur *** by a theoretical prediction,herein,we strategically propose nitrogenvacancy tantalum nitride(Ta3N5-x)impregnated inside the interconnected nanopores of nitrogendecorated carbon matrix as a new electrocatalyst for regulating sulfur redox reactions in roomtemperature sodium-sulfur *** a pore-constriction mechanism,the nitrogen vacancies are controllably constructed during the nucleation of *** defect manipulation on the local environment enables well-regulated Ta 5d-orbital energy level,not only modulating band structure toward enhanced intrinsic conductivity of Ta-based materials,but also promoting polysulfide stabilization and achieving bifunctional catalytic capability toward completely reversible polysulfide ***,the interconnected continuous Ta3N5-x-in-pore structure facilitates electron and sodium-ion transport and accommodates volume expansion of sulfur species while suppressing their shuttle *** to these attributes,the as-developed Ta3N5-x-based electrode achieves superior rate capability of 730 mAh g-1 at 3.35 A g-1,long-term cycling stability over 2000 cycles,and high areal capacity over 6 mAh cm-2 under high sulfur loading of 6.2 mg *** work not only presents a new sulfur electrocatalyst candidate for metal-sulfur batteries,but also sheds light on the controllable material design of defect structure in hopes of inspiring new ideas and directions for future research.

关键词： Tantalum nitride Nitrogen defects Sodium-sulfur batteries Electrocatalysts Polysulfide conversion

The First Five Years of a Phase Theory for Complex Systems and Networks

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IEEE/CAA Journal of Automatica Sinica 2024年第8期11卷 1728-1743页

作者： dan Wang Wei chen Li Qiu Division of Decision and Control Systems KTH Royal Institute of TechnologyStockholm 10044Sweden Department of Mechanics and Engineering Science&the State Key Laboratory for Turbulence and Complex Systems Peking UniversityBeijing 100871China Hong Kong University of Science and Technology Hong KongChinaand also with the Southern University of Science and TechnologyShenzhen 518055China

In this paper,we review the development of a phase theory for systems and networks in its first five years,represented by a trilogy:Matrix phases and their properties;The MIMO LTI system phase response,its physical interpretations,the small phase theorem,and the sectored real lemma;The synchronization of a multi-agent network using phase *** the end,we also summarize a list of ongoing research on the phase theory and speculate what will happen in the next five years.

关键词： Consensus and synchronization matrix phases multi-agent systems phase theory sectored real lemma small phase theorem.

Big Theta Equals Small Theta Generically

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Acta Mathematica Sinica,English Series 2024年第3期40卷 717-730页

作者： rui chen Jia Liang ZOU Institute for Advanced Study in Mathmatics Zhejiang UniversityHangzhou 310058P.R.China Department of Mathematics University of Michigan530 Church StAnn ArborMI 48109USA

In this paper we consider the theta correspondence over a non-Archimedean local *** the homological method and the theory of derivatives,we show that under a mild condition the bigtheta lift is irreducible.

关键词： Theta correspondence derivatives

Double Moving Extremes Ranked Set Sampling Design

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 75-90页

作者： Meng chen Wang-xue chen rui Yang Department of Mathematics and Statistics Jishou UniversityJishou416000China

The traditional simple random sampling(SRS)design method is inefficient in many *** proposed some new designs to increase *** this paper,as a variation of moving extremes ranked set sampling(MERSS),double MERSS(DMERSS)is proposed and its properties for estimating the population mean are *** turns out that,when the underlying distribution is symmetric,DMERSS gives unbiased estimators of the population ***,it is found that DMERSS is more efficient than the SRS and MERSS methods for usual symmetric distributions(normal and uniform).For asymmetric distributions considered in this study,the DMERSS has a small bias and it is more efficient than SRS for usual asymmetric distribution(exponential)for small sample sizes.

关键词： double moving extremes ranked set sampling symmetric distribution efficiency