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BCC-CSM2模式耦合同化对北极海冰次季节预测的影响

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气象学报 2024年第3期82卷 340-355页

作者：邱孙俊杰刘向文姚隽琛中国气象科学研究院北京100081 中国气象局地球系统数值预报中心北京100081

近年来北极海冰的加速融化对北半球天气和气候的影响逐渐加剧,开展准确的海冰次季节预测已成为迫切需求。基于北京气候中心气候系统模式(BCC-CSM2),采用多种耦合同化方案(大气同化、海洋-大气同化、海洋-海冰-大气同化)产生模式初值,开... 详细信息

近年来北极海冰的加速融化对北半球天气和气候的影响逐渐加剧,开展准确的海冰次季节预测已成为迫切需求。基于北京气候中心气候系统模式(BCC-CSM2),采用多种耦合同化方案(大气同化、海洋-大气同化、海洋-海冰-大气同化)产生模式初值,开展大气(FST-A)、海洋-大气(FST-AO)、海洋-海冰-大气(FST-AOI)预测试验,进而探讨了多圈层耦合同化对北极海冰次季节预测的影响。结果表明,随着耦合同化分量的增加,模式对海冰密集度气候态和变率的预测技巧逐渐提高,其中FSTAOI在所有试验中表现最优。海洋-海冰-大气同化对预测的影响存在明显的季节性差异,其在大多数月份(尤其是少冰期(9—10月))能够明显降低海冰密集度预测误差,但在快速融冰期(6—7月),若干海冰边缘区(波弗特海、东西伯利亚海、拉普捷夫海、喀拉海附近)的密集度误差随预测时间延长而快速增大。因此,多圈层耦合同化在总体上能够有效改善北极海冰次季节预测,但其在快速融冰阶段对预测的影响存在较大不确定性。进一步诊断表明,在快速融冰期,采用海洋-海冰-大气同化初值的试验在预报开始阶段(主要指第1周)低估了海冰边缘区的密集度。在海冰-反照率正反馈机制影响下,这可能导致模拟地表短波辐射吸收增加,引起海水升温和海冰融化加快,进而导致海冰误差快速增长。未来研究将致力于继续提升海洋-海冰-大气多分量耦合同化的协调,以持续改进北极海冰次季节—季节预测能力。

关键词： BCC-CSM2 耦合同化北极海冰次季节预测

Rational design of graphyne-based dual-atom site catalysts for CO oxidation

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Nano Research 2023年第1期16卷 343-351页

作者： Zhenwei Zhang Liang Zhang Xiaoyang Wang Yuan Feng xiangwen liu Wenming Sun Department of Chemistry Beijing Key Laboratory for Optical Materials and Photonic DevicesCapital Normal UniversityBeijing 100048China Linyi Vocational University of Science and Technology(Linyi Institute of Industrial Technology) Linyi 276000China Dassault Systemes(Shanghai)Information Technology Co. Ltd.Shanghai 200120China Institute of Analysis and Testing Beijing Academy of Science and Technology(Beijing Center for Physical and Chemical Analysis)Beijing 100094China TianHe Supercomputing Center of Huaihai Linyi 276000China

There are increasing concerns about the environmental impact of rising atmospheric carbon monoxide concentrations,thus it is necessary to develop new catalysts for efficient CO *** on first-principles calculations,the potential ofγ-graphyne(GY)as substrate for metals in the 4th and 5th periods under single-atom and dual-atoms concentration modes has been systematically *** was found that single-atom Co,Ir,Rh,and Ru could effectively oxidate CO molecules,especially for single ***,proper atoms concentration could boost the CO oxidation activity by supplying more reaction centers,such as Rh^(2)/*** was determined that two Rh atoms in Rh^(2)/GY act different roles in the catalytic reaction:one structural and another *** tests suggest that substituting the structural Rh atom in the center of acetylenic ring by Co or Cu atom is a possible way to maintain the reaction performance while reducing the noble metal *** systemic investigation will help in understanding the fundamental reaction mechanisms on GY-based *** emphasize that properly exposed frontier orbital of functional metal atom is crucial in adsorption configuration as well as entire catalytic *** study constructs a workflow and provides valuable information for rational design of CO oxidation catalysts.

关键词： density functional theory calculations CO oxidation single-atom catalyst graphyne dual-atom site catalyst

Progress of MJO Prediction at CMA from Phase I to Phase II of the Sub-Seasonal to Seasonal Prediction Project

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Advances in Atmospheric Sciences 2023年第10期40卷 1799-1815页

作者： Junchen YAO xiangwen liu Tongwen WU Jinghui YAN Qiaoping LI Weihua JIE Center for Earth System Modeling and Prediction of China Meteorological Administration Beijing 100081China

As one of the participants in the Subseasonal to Seasonal(S2S)Prediction Project,the China Meteorological Administration(CMA)has adopted several model versions to participate in the S2S *** study evaluates the models’capability to simulate and predict the Madden-Julian Oscillation(MJO).Three versions of the Beijing Climate Center Climate System Model(BCC-CSM)are used to conduct historical simulations and re-forecast experiments(referred to as EXP1,EXP1-M,and EXP2,respectively).In simulating MJO characteristics,the newly-developed high-resolution BCC-CSM outperforms its *** terms of MJO prediction,the useful prediction skill of the MJO index is enhanced from 15 days in EXP1 to 22 days in EXP1-M,and further to 24 days in *** the first forecast week,the better initial condition in EXP2 largely contributes to the enhancement of MJO prediction ***,during forecast weeks 2–3,EXP2 shows little advantage compared with EXP1-M because the increased skill at MJO initial phases 6–7 is largely offset by the degraded skill at MJO initial phases 2–*** at initial phases 2–3,EXP1-M skillfully captures the wind field and Kelvin-wave response to MJO convection,leading to the highest prediction skill of the *** results reveal that,during the participation of the CMA models in the S2S Project,both the improved model initialization and updated model physics played positive roles in improving MJO *** efforts should focus on improving the model physics to better simulate MJO convection over the Maritime Continent and further improve MJO prediction at long lead times.

关键词： Madden-Julian Oscillation(MJO) Subseasonal to Seasonal(S2S) prediction skill improvement initial phase

Constructing the separation pathway for photo-generated carriers by diatomic sites decorated on MIL-53-NH2(Al)for enhanced photocatalytic performance

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Nano Research 2022年第8期15卷 7034-7041页

作者： Gang Wang Yan liu Ning Zhao Huimei Chen Wenjie Wu Yueyue Li xiangwen liu Ang Li Wenxing Chen Junjie Mao Key Laboratory of Functional Molecular Solids Ministry of EducationCollege of Chemistry and Materials ScienceAnhui Normal UniversityWuhu 241002China Institute of Analysis and Testing Beijing Academy of Science and Technology(Beijing Center for Physical and Chemical Analysis)Beijing 100094China Beijing Key Laboratory of Microstructure and Property of Advanced Materials Beijing University of TechnologyBeijing 100124China Beijing Key Laboratory of Construction Tailorable Advanced Functional Materials and Green Applications School of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081China

High yield production of phenol from hydroxylation of benzene with low energy consumption is of paramount importance,but still ***,a new strategy,consisting of using diatomic synergistic modulation(DSM)to effectively control the separation of photo-generated carriers for an enhanced production of phenol is *** atomic level dispersion of Fe and Cr respectively decorated on Al based MIL-53-NH_(2)photocatalyst(Fe1/Cr:MIL-53-NH_(2))is designed,in which Cr single atoms are substituted for Al3+while Fe single atoms are coordinated by ***,the Fe1/Cr:MIL-53-NH_(2)significantly boosts the photooxidation of benzene to phenol under visible light irradiation,which is much higher than those of MIL-53-NH_(2),Cr:MIL-53-NH_(2),Fe1/MIL-53-NH_(2),and Fe nanoparticles/Cr:MIL-53-NH_(2)*** and experimental results reveal that the Cr single atoms and Fe single atoms can act as electron acceptor and electron donor,respectively,during photocatalytic reaction,exhibiting a synergistic effect on the separation of the photo-generated carriers and thereby causing great enhancement on the benzene *** strategy provides new insights for rational design of advanced photocatalysts at the atomic level.

关键词： diatomic sites MIL-53-NH2 charge-carrier dynamics photocatalysis benzene oxidation

Histone post-translational modification and the DNA damage response

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Genes & Diseases 2023年第4期10卷 1429-1444页

作者： Haoyun Song Rong Shen xiangwen liu Xuguang Yang Kun Xie Zhao Guo Degui Wang School of Basic Medical Sciences Lanzhou UniversityLanzhouGansu 730000China

DNA is highly vulnerable to spontaneous and environmental timely damage in living *** damage may cause genetic instability and increase cancer risk if the damages are not repaired timely and *** cells possess several DNA damage response(DDR)mechanisms to protect the integrity of their *** of the mechanisms under-lying the DNA damage response following lethal damage will facilitate the identification of therapeutic targets for *** post-translational modifications(PTMs)have been indicated to play different roles in the repair of DNA *** this context,histone PTMs regulate recruitment of downstream effectors,and facilitate appropriate repair *** review outlines the current understanding of different histone PTMs in response to DNA dam-age repair,besides,enumerates the role of new type PTMs such as histone succinylation and crotonylation in regulating DNA damage repair processes.

关键词： DNA damage DNA damage response Histone Post-translational modifications(PTMs)

Relationship between hydrogenation degree and pyrolysis performance of jet fuel

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Chinese Journal of Chemical Engineering 2024年第4期68卷 35-42页

作者： Qing liu Tinghao Jia Lun Pan Jijun Zou xiangwen Zhang Key Laboratory for Green Chemical and Technology School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China Zhejiang Institute of Tianjin University Ningbo 315201China Zhejiang Provincial Key Laboratory of Advanced Chemical Engineering Manufacture Technology College of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310027China

Understanding the relationship between the chemical composition and pyrolysis performance of endothermic hydrocarbon fuel(EHF) is of great significance for the design and optimization of advanced EHFs. In this work, the effect of deep hydrogenation on the pyrolysis of commercial RP-3 is *** with different hydrogenation degrees were obtained by the partially and completely catalytic hydrogenation and their pyrolysis performances were investigated using an apparatus equipped with an electrically heated tubular reactor. The results show that with the increase of hydrogenation degree, fuel conversion almost remains constant during the pyrolysis process(500-650°C, 4 MPa);however, the heat sink increases slightly, and the anti-coking performance significantly improves, which are highly related to their H/C ratios. Detailed characterisations reveal that the difference of the pyrolysis performance can be ascribed to the content of aromatics and cycloalkanes: the former are prone to initiate secondary reactions to form coking precursors, while the latter could act as the hydrogen donor and release hydrogen, which will terminate the radical propagation reactions and suppress the coke deposition. This work should provide the guidance for upgrading EHFs by modulating the composition of EHFs.

关键词： RP-3 Fuel Pyrolysis Hydrogenation Deposition

Upper-Ocean Lateral Heat Transports in the Nino3.4 Region and Their Connection with ENSO

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Journal of Meteorological Research 2022年第2期36卷 360-373页

作者： He ZHAO Tongwen WU Laurent ZXLI Fanghua WU Weihua JIE xiangwen liu Ronghua ZHANG Chengjun XIE Chinese Academy of Meteorological Sciences China Meteorological AdministrationBeijing 100081China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Beijing Climate Center China Meteorological AdministrationBeijing 100081China Laboratoire de Météorologie Dynamique Centre National de la Recherche ScientifiqueSorbonne UniversitéEcole Normale SupérieureEcole PolytechniqueParis 75252France Key Laboratory of Ocean Circulation and Waves Institute of Oceanologyand Center for Ocean Mega-ScienceChinese Academy of SciencesQingdao 266071China Center for Excellence in Quaternary Science and Global Change Chinese Academy of SciencesXi’an 710061China

In the Nino3.4 region(tropical Pacific,5°S-5°N,170°-120°W),sea surface temperature(SST)changes are highly correlated with temperature variations in the upper 40-m *** study explores the upper-ocean heat budget in the Nino3.4 region using Ocean Reanalysis System 5(ORAS5)monthly data from 1979 to 2018,with a focus on ocean heat transports at lateral boundaries in the top 40-m layer and their correlation with temperature *** the region,there is a well-defined structure of opposite meridional circulation in the upper and lower parts of the thermocline,characterized by divergence in the upper layer above 40 m and convergence in the lower *** change of mean temperature in the upper layer is determined by the sum of zonal,meridional,and vertical heat transports,which,however,tend to largely compensate for each *** general,part of the surface heat flux from the atmosphere to the ocean and the heat transport from the subsurface ocean are transported out of the domain by meridional and zonal currents,leaving only a tiny part to warm or cool the upper *** amplitude of the net surface heat flux effective for the entire 40-m layer of the ocean is weaker than the lateral heat *** an interannual timescale,variations of heat transports in both zonal and meridional are positively correlated with temperature anomalies,while the vertical heat transport from the subsurface ocean is negatively *** analyses for five El Nino events and five La Nina events also revealed that there is a positive contribution of horizontal transport convergence to temperature anomalies during the evolution of El Nino(warming)and La Nina(cooling),while vertical transport acts against temperature variations.

关键词： heat budget lateral heat transport surface heat flux Ni?o3.4 region El Nino–Southern Oscillation(ENSO)

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新能源并网技术面临的挑战与解决方案

通信电源技术 2024年第15期41卷 201-203页

作者：刘祥文陈龙贺尔文罗盛李可欣贵州电网有限责任公司兴义供电局贵州兴义562400

随着全球能源危机和环境问题的日益严峻,新能源作为一种清洁、可再生的能源形式,正逐渐成为各国能源战略的重要组成部分。风能、太阳能、海洋能等新能源以其丰富性和环保特性得到了广泛应用。然而,这些新能源的间歇性和不稳定性给电力... 详细信息

随着全球能源危机和环境问题的日益严峻,新能源作为一种清洁、可再生的能源形式,正逐渐成为各国能源战略的重要组成部分。风能、太阳能、海洋能等新能源以其丰富性和环保特性得到了广泛应用。然而,这些新能源的间歇性和不稳定性给电力系统的稳定运行带来了诸多挑战。特别是在并网过程中,如何有效解决新能源发电的波动性、间歇性及不可控性等问题,成为当前电力工程领域的研究热点。文章通过分析新能源并网过程中所面临的主要挑战,提出针对性的优化策略。

关键词：新能源并网技术稳定性功率质量

Investigating the ENSO prediction skills of the Beijing Climate Center climate prediction system version 2

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Acta Oceanologica Sinica 2022年第5期41卷 99-109页

作者： Yanjie Cheng Youmin Tang Tongwen Wu Xiaoge Xin xiangwen liu Jianglong Li Xiaoyun Liang Qiaoping Li Junchen Yao Jinghui Yan CMA Earth System Modeling and Prediction Centre China Meteorological Administration(CMA)Beijing100081China State Key Laboratory of Severe Weather China Meteorological AdministrationBeijing100081China College of Environmental Science and Engineering University of Northern British ColumbiaPrince GeorgeV2N 4Z9Canada

The El Niño-Southern Oscillation(ENSO)ensemble prediction skills of the Beijing Climate Center(BCC)climate prediction system version 2(BCC-CPS2)are examined for the period from 1991 to *** upper-limit ENSO predictability of this system is quantified by measuring its“potential”predictability using information-based metrics,whereas the actual prediction skill is evaluated using deterministic and probabilistic skill *** show that:(1)In general,the current operational BCC model achieves an effective 10-month lead predictability for ***,prediction skills are up to 10–11 months for the warm and cold ENSO phases,while the normal phase has a prediction skill of just 6 months.(2)Similar to previous results of the intermediate coupled models,the relative entropy(RE)with a dominating ENSO signal component can more effectively quantify correlation-based prediction skills compared to the predictive information(PI)and the predictive power(PP).(3)An evaluation of the signal-dependent feature of the prediction skill scores suggests the relationship between the“Spring predictability barrier(SPB)”of ENSO prediction and the weak ENSO signal phase during boreal spring and early summer.

关键词： ENSO ensemble prediction skill potential predictability measure BCC-CPS2 climate model