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Increase in the variability of terrestrial carbon uptake in response to enhanced future ENSO modulation

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Atmospheric and Oceanic Science Letters 2025年第01期 34-40页

作者： Younong li li Dan Jing peng Qidong Yang Fuqiang Yang Key Laboratory of Regional Climate-Environment for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences Key Laboratory of Atmospheric Environment and Processes in the Boundary Layer over the Low-Latitude Plateau Region Department of Atmospheric Science Yunnan University

ENSO是中低纬度地区气候系统的主要驱动因素,对陆地碳循环有重要影响.本研究基于10个CMIP6地球系统模式,分析了不同情景下ENSO变率与中低纬度地区总初级生产力变率的关系.结果显示,未来ENSO变率和总初级生产力变率在未来多数模式均显示... 详细信息

ENSO是中低纬度地区气候系统的主要驱动因素,对陆地碳循环有重要影响.本研究基于10个CMIP6地球系统模式,分析了不同情景下ENSO变率与中低纬度地区总初级生产力变率的关系.结果显示,未来ENSO变率和总初级生产力变率在未来多数模式均显示为增加.在未来情境下(2051-2100年),中低纬度地区的总初级生产力变率较历史时期(1951–2000年)增加了30.9%(SSP2-4.5), 58.2%(SSP5-8.5).进一步分析表明, ENSO主要通过温度影响中低纬度碳通量变率.这种现象可能归因于总初级生产力对温度的响应增强,以及ENSO对陆地表面温度的影响.

关键词：总初级生产力 ENSO变率 CMIP6

Synthesis of chiral phosphine derivatives through a copper（I）-catalyzed desymmetric SNAr reaction

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Science China Chemistry 2025年

作者： Shuai Zhang Pei-Zhi liu Yan-Bo li Qi Zhang Jun-Zhao Xiao Yi-Fan Wang Tian-Yu Wei Jia-Wei Jiang Ye Wang Qian peng liang Yin Key Laboratory of Fluorine and Nitrogen Chemistry and Advanced Materials Shanghai Institute of Organic Chemistry University of Chinese Academy of Sciences Chinese Academy of Sciences State Key Laboratory of Elemento-Organic Chemistry and Tianjin Key Laboratory of Biosensing and Molecular Recognition College of Chemistry Frontiers Science Center for New Organic Matter Nankai University Haihe Laboratory of Sustainable Chemical Transformations

Axially chiral phosphines are a class of extremely important ligands in asymmetric catalysis. Herein, an unprecedented copper（I）-catalyzed asymmetric SNAr reaction with HP（S）R2is uncovered, which delivers a series of axially chiral phosphine derivatives in high yields with excellent enantioselectivity. Furthermore, the diastereoselective reaction with the kinetic resolution of racemic HP（S）ArR proceeds smoothly, providing the products with moderate diastereoselectivity and excellent enantioselectivity. Control experiments indicate that HP（S）Ph2is much more active than HPPh2and HP（O）Ph2as the pronucleophile in the present reaction. It is found that the SNAr reaction （the first SNAr） proceeds in a desymmetric manner, providing the desired chiral products while a continued SNAr reaction （the second SNAr） slightly occurs in a kinetic resolution manner in the present catalytic system, which enhances the ee of the desired chiral products. DFTcalculations support a concerted reaction pathway rather than a step-wise mechanism. Finally, axially chiral olefin-phosphines produced by the present method work as suitable ligands in Pdcatalyzed asymmetric allylic substitution with C-, N-, and O-nucleophiles and Rh-catalyzed asymmetric addition of arylboronic acid to benzil.

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Highly Efficient Random Terpolymers for Photovoltaic Applications with Enhanced Absorption and Molecular Aggregation

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Chinese Journal of Polymer Science 2017年第2期35卷 249-260页

作者： Xiao-peng Xu guang-jun Zhang Yun-zhe Zhao 刘江 Ying li 彭强 Key Laboratory of Green Chemistry and Technology of Ministry of Education College of ChemistryState Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610064China Chengdu Green Energy and Green Manufacturing Technology R&D Center Chengdu 610207China

A series of copolymers, based on benzo[1,2-b：4,5-b＇]dithiophene （BDT） as the electron donor and 2,1,3- benzothiadiazole （BT）/diketopyrrolo[3,4-c]pyrrole （DPP） as the electron acceptors, were synthesized for highly efficient polymer solar cells. By changing the BT/DPP ratio in the conjugated backbone, the absorption, energy levels, molecular aggregation and carrier mobility could be finely tuned. With increased DPP content, the absorption range was extended to the longer wavelength region with narrower bandgaps. The highest occupied molecular orbital （HOMO） levels were also raised up and the molecular aggregation was enhanced. The balance of these factors would afford a remarkable device performance enhancement. Polymer P3 with BT：DPP = 0.7：0.3 （molar ratio） exhibited the highest power conversion efficiency （PCE） of 9.01%, with open circuit voltage （Voc） = 0.73 V, short current density （Jsc） = 18.45 ***-2, and fill factor （FF） - 66.9%. The PCE value was improved by 48.7% compared to P1 and by 117.6% compared to P7, respectively, indicating a great potential in photovoltaic application.

关键词： Polymer solar cells Terpolymers Complementary absorption Molecular aggregation

A new car-following model with driver's anticipation effect of traffic interruption probability

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Chinese Physics B 2020年第8期29卷 349-354页

作者： guang-Han peng College of Physical Science and Technology Guangxi Normal UniversityGuilin 541004China

Traffic interruption phenomena frequently occur with the number of vehicles *** investigate the effect of the traffic interruption probability on traffic flow,a new optimal velocity model is constructed by considering the driver anticipation term in the interruption case for car-following ***,the effect of driver anticipation in the interruption case is investigated via linear stability ***,the MKdV equation is obtained concerning the effect of driver anticipation in the interruption ***,numerical simulation states that the driver anticipation term in the interruption case contributes to the stability of traffic flow.

关键词： traffic flow interruption probability optimal velocity model numerical simulation

A dual-site Fe-based catalyst for efficient ammonia synthesis under mild conditions

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Science China Chemistry 2025年

作者： Shiyong Zhang Mingyuan Zhang Tianhua Zhang Jizhen Sun Jiaxin li Kailin Su Ruishao Mao Yanliang Zhou Xuanbei peng Yangyu Zhang Jun Ni Bingyu lin Xiuyun Wang lilong Jiang National Engineering Research Center of Chemical Fertilizer Catalyst Fuzhou University Qingyuan Innovation Laboratory

Achieving green ammonia （NH3） synthesis requires developing effective catalysts under mild ***,the competitive adsorption of N2and H2,as well as the strong binding of N-containing intermediates on the catalyst,greatly inhibits the active sites for efficient ***,we constructed a series of ZrH2-modified Fe catalysts with dual active sites to address these issues and realized efficient NH3synthesis under mild *** study shows that ZrH2can not only provide active sites for H2activation but also transfer electrons to Fe sites for accelerating *** interaction between Fe and ZrH2over 40ZrH2-Fe leads to a decrease in work function and a downward shift of the d-band center,which is conducive to N2activation and NH3desorption,*** utilization of distinct sites for activating different reactants can avoid the competitive adsorption of N2and H2,leading to excellent NH3synthesis activity of the 40 wt.%ZrH2-mediated Fe *** a result,40ZrH2-Fe exhibits a high NH3synthesis rate of 23.3 mmol g-1cath-1at 400°C and 1 MPa and robust stability during100 h time-on-stream.

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掺炼油浆对原油蒸馏过程及沥青性质的影响

石化技术与应用 2017年第2期35卷 106-111页

作者：李福起金吉海王兴裴晓光李朋杨国明中海油炼油化工科学研究院(北京)有限公司北京100000

以催化油浆为强化剂,对绥中36-1原油进行实沸点蒸馏,考察了掺兑油浆对馏分油收率、沥青及侧线油性质的影响,并分析了油浆对原油蒸馏的作用机理。结果表明:在相同的蒸馏温度下,随着油浆掺兑比的增大,馏分油的收率逐渐增加,沥青的针入度... 详细信息

以催化油浆为强化剂,对绥中36-1原油进行实沸点蒸馏,考察了掺兑油浆对馏分油收率、沥青及侧线油性质的影响,并分析了油浆对原油蒸馏的作用机理。结果表明:在相同的蒸馏温度下,随着油浆掺兑比的增大,馏分油的收率逐渐增加,沥青的针入度则逐渐降低;在蒸馏相同标号的沥青时,掺兑油浆使原油的蒸馏温度降低;与原油直馏沥青相比,掺兑油浆所得沥青的针入度指数及动力黏度(60℃)逐渐降低,四组分中饱和分、胶质含量增加,芳香分、沥青质含量降低;随着油浆掺兑比的增大,原油蒸馏200~450℃侧线油的运动黏度、密度(20℃)及各馏程段的恩氏蒸馏温度均逐渐降低;原油蒸馏过程中掺兑油浆,芳香分对馏分油收率的促进作用与表面张力对其的抑制作用同时存在。

关键词：原油催化油浆实沸点蒸馏沥青馏分油收率沥青四组分蒸馏温度

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论宣王中兴与王官诗学的裂变

保山学院学报 2025年第1期44卷 82-87页

作者：李鹏安徽师范大学文学院安徽芜湖241002 亳州学院中文与传媒系安徽亳州236800

《大小雅》中存有大量周宣王朝诗,这与宣王中兴有关。“雅中之颂”“‘变雅’作矣”两组感情色彩迥异的诗同时存在于诗文本中,是宣王时期政治社会生态的折射。宣王朝诗文本的编辑活动,以服务礼乐仪式为目的,但客观上导致了诗歌讽谏功能... 详细信息

《大小雅》中存有大量周宣王朝诗,这与宣王中兴有关。“雅中之颂”“‘变雅’作矣”两组感情色彩迥异的诗同时存在于诗文本中,是宣王时期政治社会生态的折射。宣王朝诗文本的编辑活动,以服务礼乐仪式为目的,但客观上导致了诗歌讽谏功能的长足发展,进而引发了王官诗学的裂变。从此,诗教由乐教附庸而趋向独立,并朝着注重德教的伦理化方向发展。

关键词：宣王中兴雅中之颂 “变雅”作矣王官诗学

Radio recombination line observations at 1.0-1.5 GHz with FAST

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Research in Astronomy and Astrophysics 2021年第8期21卷 269-274页

作者： Chuan-peng Zhang Jin-Long Xu guang-Xing li li-Gang Hou Nai-Ping Yu peng Jiang National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China CAS Key Laboratory of FAST National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China South-Western Institute for Astronomy Research Yunnan UniversityKunming 650500China

H Ⅱ regions made of gas ionized by radiations from young massive stars,are widely distributed in the Milky *** are tracers for star formation,and their distributions are correlated with the Galactic spiral *** recombination lines(RRLs) of hydrogen and other atoms allow for the most precise determination of physical parameters such as temperature and ***,RRLs at around 1.4 GHz from HⅡ regions are weak and their detections are *** a result,only a limited number of detections have been obtained *** 19-beam receiver on board of the Five-hundred-meter Aperture Spherical radio Telescope(FAST) can simultaneously cover 23 RRLs for Hnα,Henα,and Cnα(n=164-186),***,combined with its unparalleled collecting area,makes FAST the most powerful telescope to detect weak *** this pilot survey,we use FAST to observe nine HⅡ regions at L *** allocate20 minutes pointing time for each source to achieve a sensitivity of around 9 mK in a velocity resolution of2.0 km s^(-1).In total,21 RRLs for Hnα and Cnα at 1.0-1.5 GHz have been simultaneously detected with strong emission ***,the detection rates for the H167α and C167α RRLs are 100%,while that for the He167α RRL is 33.3%.Using hydrogen and helium RRLs,we measure the electron density,electron temperature,and pressure for three HⅡ *** pilot survey demonstrates the capability of FAST in RRL measurements,and a statistically meaningful sample with RRL detection,through which knowledge about Galactic spiral structure and evolution can be obtained,is expected in the future.

关键词： telescopes:FAST HⅡregions radio lines:ISM galaxies:star formation

Lattice Boltzmann method for simulating flows in open-channel with partial emergent rigid vegetation cover

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Journal of Hydrodynamics 2019年第4期31卷 717-724页

作者： Zhong-hua Yang Feng-peng Bai Wen-xin Huai Cheng-guang li State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University Wuhan 430072 China Changjiang Water Resources Protection Institute Wuhan 430051 China Shandong Provincial Key Laboratory of Water Resources and Water Environment Water Resources Research Institute of Shandong Province Jinan 250013 China

Flows in open-channel with partial emergent rigid vegetation cover are simulated using the lattice Boltzmann method (LBM) described by the 2-D nonlinear shallow water equations. The effect of vegetation is represented with the vegetation roughness coefficient, which is related to the vegetation density, diameter of the vegetation elements and drag coefficient. The model is verified by three numerical tests: flow in a 180° curved open channel with partial vegetation cover at the outer bank, flow in a rectangular channel with a finite patch of vegetation and flow in a rectangular channel with a vegetated bank. Numerical results are compared with the experimental data, and the good agreement proved that the presented model can model the vegetated channel flows correctly.

关键词： Open-channel flow rigid vegetation lattice Boltzmann method (LBM) shallow water equations vegetation roughness coefficient