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Effect of precession on the Asian summer monsoon evolution:A systematic review

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Chinese Science Bulletin 2009年第20期54卷 3720-3730页

作者： LIU XiaoDong shi zhengguo State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi'an 710075 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

Geological climatic records and model simulations on the Asian summer monsoon climate change induced by insolation forcing of the Earth's precession are systematically reviewed in this *** presentation of the questions on the mechanism of the Asian monsoon evolution at the precession band,currently existing debates and future research directions are *** the early 1980s,more and more observed evidence and simulated results,especially the absolute-dated stalagmite records and orbital-scale transient model runs in the last few years,have indicated that the quasi-20ka period in the Quaternary monsoon climate change is caused by ***,debates still exist on the dynamic mechanism how precession affects the Asian *** "zero phase" hypothesis says that the Asian monsoon is merely controlled by summer insolation in the Northern Hemisphere(NH) while the "latent heat" hypothesis emphasizes the dominant effect of latent heat transport from the Southern Hemisphere(SH) besides the role of the northern *** two hypotheses have separately been supported by some *** we are cognizant of the importance of northern solar radiation and the remote effect of southern insolation,it has still a long way to go before comprehensively understanding the evolutionary mechanism of the Asian *** view of the problems existing in present researches of monsoon-dominated climate change at the precession scale,we propose that studies on the environmental significance of geological monsoon proxies,feedback processes in the long-term transient simulations and intercomparisons between observations and modeling results should be strengthened in the future.

关键词：系统评价夏季季风进动效应演变亚洲

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化工医药企业打造新质生产力途径的探讨

山东化工 2024年第14期53卷 98-99,102页

作者：徐立飞石正国龙丹梅贵州应用技术职业学院贵州福泉550500 贵州轻工职业技术学院贵州贵安550025

随着科技的不断进步和市场环境的快速变化,化工医药企业面临着前所未有的挑战与机遇。新质生产力作为近年来研究的热点,对于化工医药企业的转型升级和持续发展具有重要意义。本文通过剖析新质生产力的研究进展,探讨化工医药企业如何通... 详细信息

随着科技的不断进步和市场环境的快速变化,化工医药企业面临着前所未有的挑战与机遇。新质生产力作为近年来研究的热点,对于化工医药企业的转型升级和持续发展具有重要意义。本文通过剖析新质生产力的研究进展,探讨化工医药企业如何通过技术改进、专利-标准的系列化措施、数据资产与知识资产的品牌化建设、管理创新来打造新质生产力,进而提升企业的生产效率、行业竞争力及品牌影响力,增加在发展优质软资产的直接收益。

关键词：新质生产力创新管理数据资产企业发展

Simulation of the climatic effects of natural forcings during the pre-industrial era

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Chinese Science Bulletin 2007年第11期52卷 1545-1558页

作者： YIN ChongHua YAN XiaoDong shi zhengguo WANG ZhaoMin Key Laboratory of Climate-Environment for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China British Antarctic Survey High Cross Madingling Road Cambridge CB3 0ET UK Graduate University of Chinese Academy of Sciences Beijing 100049 China

The MPM-2,an Earth system model of intermediate complexity,is employed to study the climate sys-tem response to natural forcings during the pre-industrial era (1000-1800 AD),with a special focus on the surface air temperature (SAT) evolution. Solar radiation and volcanism are the primary natural forcings during this period. In the MPM-2,the solar radiation forcing determines the long-term trend of the climate system change,and the volcanic forcing intensifies (weakens) this trend. Ultimately,the combination of solar and volcanic forcings dominates the long-term changes of the climate system. These results are in good agreement with other model data or temperature reconstructions. Natural forcings can well explain the Little Ice Age (LIA) and the Medieval Warm Period (MWP). At the large regional scale,the SAT response to natural forcings is almost coincident with that of the Northern Hemisphere. Based on MPM-2 model results,it is concluded that the global climate gradually became cold during the pre-industrial era. However,MPM-2 model results substantially correlate with recon-structed solar and volcanic forcings. Namely,to some great extent,these results strongly rely on the forcing series data we choose. Therefore,in order to accurately simulate the secular variation of the historical climate,it is very important to reconstruct well the solar radiation change and volcanic forc-ing data are well reconstructed for the past 10000 years,at least for the past 2000 years,in addition to the model improvements. The sensitivity study on the abrupt solar radiation change indicates that the increased solar radiation not only strengthens the nonlinear response of SAT,but intensifies the global hydrological cycle. At the same time,the biosphere is also affected obviously.

关键词：冰河时代火山作用仿真模拟日光气候因素前工业时代

Effects of historical land cover changes on climate

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Chinese Science Bulletin 2007年第18期52卷 2575-2583页

作者： shi zhengguo YAN XiaoDong YIN ChongHua WANG ZhaoMin Key Laboratory of Regional Climate-Environment Research for Temperate East Asia Chinese Academy of Sciences Beijing 100029 China Graduate University of Chinese Academy of Sciences Beijing 100049 China British Antarctic Survey Cambridge CB30ET UK

In order to explore the influence of anthropogenic land use on the climate system during the last mil- lennium, a set of experiments is performed with an Earth system model of intermediate complexity—— the McGill Paleoclimate Model (MPM-2). The present paper mainly focuses on biogeophysical effects of historical land cover changes. A dynamic scenario of deforestation is described based on changes in cropland fraction (RF99). The model simulates a decrease in global mean annual temperature in the range of 0.09-0.16℃, especially 0.14-0.22℃ in Northern Hemisphere during the last 300 years. The responses of climate system to GHGs concentration changes are also calculated for comparisons. Now, afforestation is becoming an important choice for the enhancement of terrestrial carbon sequestration and adjustment of regional climate. The results indicate that biogeophysical effects of land cover changes cannot be neglected in the assessments of climate change.

关键词：气候变化陆地覆盖森林开伐气候-生物圈相互作用

Construction and properties of venlafaxine hydrochloride sustained release system based on hollow mesoporous silica microspheres

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Particuology 2024年第3期86卷 205-210页

作者： Chenjing Liang Lingling shi zhengguo Chen Lan Zhou Zhaoxia Zhang Guoqing Zhang School of Materials Science and Engineering Zhejiang Sci-tech UniversityHangzhouChina College of Textile Science and Engineering Zhejiang Sci-tech UniversityHangzhouChina Zhejiang Provincial Innovation Center of Advanced Textile Technology ShaoxingChina

The aim of this work is to develop a venlafaxine hydrochloride sustained release system based on hollow mesoporous silica microspheres(HMSMs).HMSMs were innovatively prepared with tetraethyl silicate(TEOS)as the precursor and volatile n-heptane as a soft *** obtained HMSMs show a well-defined hollow structure with an average size of 967 nm and pore volume of 0.85 cm^(3)/g,implying it is a potential drug ***,venlafaxine hydrochloride(VF)was absorbed in the HMSMs with a content of 37.67% or *** sustained release effect is further measured by the dissolution in-strument at 37℃ and 50 rpm in ultrapure *** results showed that the HMSMs/VF system shows good sustained release properties compared with sustained release tablets with hydroxypropyl meth-ylcellulose as the main *** HMSMs sustained release system appears to be a promising candidate for a sustained drug release.

关键词： Hollowmesoporous silica microspheres(HMSMs) Venlafaxine hydrochloride Drug loading Sustained release

Orbital-scale Asian summer monsoon variations:Paradox and exploration

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Science China Earth Sciences 2021年第4期64卷 529-544页

作者： Hai CHENG Haiwei ZHANG Yanjun CAI zhengguo shi Liang YI Chenglong DENG Qingzhen HAO Youbing PENG Ashish SINHA Hanying LI Jingyao ZHAO Ye TIAN Jonathan BAKER Carlos PEREZ-MEJIAS Institute of Global Environmental Change Xi'an Jiao tong UniversityXi'an 710054China State Key Laboratory^of Loess and Quaternary Geology1 Institute of Earth EnvironmentChinese Academy of SciencesXi'an 710061China Key Laboratory of Karst Dynamics Ministry of Land and ResourcesInstitute of Karst GeologyChinese Academy of Geological SciencesGuilin 541004China State Key Laboratory of Marine Geology Tongji UniversityShanghai 200092China State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Department of Earth Sciences California State University Dominguez HillsCarson 90747USA

The Asian summer monsoon(ASM) is a vast climate system, whose variability is critical to the livelihoods of billions of people across the Asian continent. During the past half-century, much progress has been made in understanding variations on a wide range of timescales, yet several significant issues remain unresolved. Of note are two long-standing problems concerning orbital-scale variations of the ASM.(1) Chinese loess magnetic susceptibility records show a persistent glacial-interglacial dominated ~100 kyr(thousand years) periodicity, while the cave oxygen-isotope(δ18 O) records reveal periodicity in an almost pure precession band(~20 kyr periodicity)—the "Chinese 100 kyr problem".(2) ASM records from the Arabian Sea and other oceans surrounding the Asian continent show a significant lag of 8–10 kyr to Northern Hemisphere summer insolation(NHSI), whereas the Asian cave δ18 O records follow NHSI without a significant lag—a discrepancy termed the "sea-land precession-phase paradox". How can we reconcile these differences? Recent and more refined model simulations now provide spatial patterns of rainfall and wind across the precession cycle, revealing distinct regional divergences in the ASM domain, which can well explain a large portion of the disparities between the loess, marine, and cave proxy records. Overall, we also find that the loess, marine, and cave records are indeed complementary rather than incompatible, with each record preferentially describing a certain aspect of ASM dynamics. Our study provides new insight into the understanding of different hydroclimatic proxies and largely reconciles the "Chinese 100 kyr problem" and "sea-land precession-phase paradox".

关键词： ASM Orbital cycles Precession phase Different climatic proxies

Interacting topological magnons in a checkerboard ferromagnet

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Chinese Physics B 2024年第3期33卷 596-601页

作者：朱恒施洪潮唐政国唐炳 Department of Physics Jishou UniversityJishou 416000China

This work is devoted to studying the magnon-magnon interaction effect in a two-dimensional checkerboard ferromagnet with the Dzyaloshinskii-Moriya *** a first-order Green function method,we analyze the influence of magnon-magnon interaction on the magnon band *** find that Chern numbers of two renormalized magnon bands are different above and below the critical temperature,which means that the magnon band gap-closing phenomenon is an indicator for one topological phase transition of the checkerboard *** results show that the checkerboard ferromagnet possesses two topological phases,and its topological phase can be controlled either via the temperature or the applied magnetic field due to magnon-magnon ***,it is found that the topological phase transition can occur twice with the increase in the temperature,which is different from the results of the honeycomb ferromagnet.

关键词： topological magnons magnon-magnon interactions topological phase transitions checkerboard ferromagnets

以蒙古高原小地形为例对青藏高原动力气候效应的探讨

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第四纪研究 2016年第4期36卷 953-960页

作者：石正国沙莹莹中国科学院地球环境研究所黄土与第四纪地质国家重点实验室西安710061 中国科学院青藏高原地球科学卓越中心北京100101 全球变化研究协同创新中心北京100875 中国科学院大学北京100049

青藏高原隆升对亚洲乃至全球气候演化的影响是古气候学热点问题之一。青藏高原的热力和动力效应一直以来受到人们的广泛重视，其中高原对大气环流的阻碍作用被认为在亚洲冬季气候形成中扮演着极其重要的作用。过去的理论及重建研究大都... 详细信息

青藏高原隆升对亚洲乃至全球气候演化的影响是古气候学热点问题之一。青藏高原的热力和动力效应一直以来受到人们的广泛重视，其中高原对大气环流的阻碍作用被认为在亚洲冬季气候形成中扮演着极其重要的作用。过去的理论及重建研究大都强调青藏高原主体的贡献，忽略了高原边缘中小尺度地形的可能贡献。以青藏高原北边缘蒙古地形为例，现代大气流场显示蒙古地形对冬季对流层低层西风具有明显的阻碍作用。本研究利用一个海气耦合模式评估了蒙古地形对亚洲冬季气候的影响及其同青藏高原主体的相对贡献。结果显示，蒙古高原地形对亚洲西风急流和东亚冬季风具有非常显著的影响。蒙古高原存在时，东亚大槽加深，日本上空的西风急流增强，东亚冬季风环流也增强。该效应主要源自于亚洲大气热力结构的变化，对流层低层西风在蒙古地形的动力强迫下向北绕流，在下游产生强烈的北风异常，有利于极地冷空气南下。该温度冷平流最终导致西风急流和冬季风环流的响应。值得注意的是，青藏高原主体对西风急流和冬季风的贡献要明显弱于蒙古高原。该结果启示我们，传统认识的青藏高原动力效应可能被一定程度高估，亚洲各地形的动力效应不仅同其规模和高度有关，也与其所处位置有关，处于敏感区域的较小尺度地形同样会对亚洲气候形成有不可忽略的影响。

关键词：青藏高原蒙古高原西风急流东亚季风动力效应

轨道尺度亚洲气候演化机理的数值模拟:历史与展望

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第四纪研究 2020年第1期40卷 8-17页

作者：石正国雷婧周朋任鑫中国科学院地球环境研究所黄土与第四纪地质国家重点实验室陕西西安710061 中国科学院第四纪科学与全球变化卓越创新中心陕西西安710061 西安交通大学全球环境变化研究院陕西西安710049 北京师范大学地球科学前沿交叉研究中心北京100875

轨道尺度亚洲气候演化是古气候热点问题之一,其变化过程和机理对理解当前全球变暖下亚洲气候变化具有重要参考意义。最近几十年,基于黄土、石笋、湖泊等载体的轨道尺度亚洲气候重建研究获得显著进展,气候演化历史的基本框架已被构建,不... 详细信息

轨道尺度亚洲气候演化是古气候热点问题之一,其变化过程和机理对理解当前全球变暖下亚洲气候变化具有重要参考意义。最近几十年,基于黄土、石笋、湖泊等载体的轨道尺度亚洲气候重建研究获得显著进展,气候演化历史的基本框架已被构建,不同区域和指标记录之间的差异暗示了气候演化机理的复杂性。数值模拟作为研究气候动力学的重要工具之一,在轨道尺度亚洲气候变化中也得到广泛应用和快速发展。基于此,本文尝试对最近十数年轨道尺度亚洲气候演化机理的数值模拟研究做一简单总结和梳理。目前的数值模拟尚未对地质记录给出的各种变化特征、区域差异等现象,尤其是东亚夏季风的黄土和石笋差异、季风和干旱气候的耦合关系等,给出合理解释。因此,在未来工作中亟须涵盖多轨道旋回的高分辨率瞬变试验,结合良好定年的重建记录,以期对轨道尺度亚洲气候变化机理获得更深入完整的认识。

关键词：亚洲气候轨道尺度动力机制数值模拟