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Glacial-interglacial cycles recorded in clay minerals from the eastern Tibetan Plateau over the last 800 ka and their indications

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Science China Earth Sciences 2024年第7期67卷 2162-2177页

作者： Xiaoyan ZHANG Chunxia ZHANG Yan ZHAO Bin HU zhengtang GUO Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China College of Earth Science and Engineering Shandong University of Science and TechnologyQingdao 266590China Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China

Clay mineral proxies have been widely used to reconstruct changes in provenance and the ***,high-altitude clay mineral indications and long-term and orbital variations have not been fully ***,we present an800-ka clay-mineral record from a lacustrine sediment core(ZB13-C2.from the Zoige Basin on the eastern Tibetan Plateau(TP).X-ray diffraction and scanning electron microscopy were used to identify the clay mineral assemblages and their micromorphological characteristics of core *** results revealed that the clay minerals in core ZB13-C2.are mainly illite,with small amounts of chlorite,kaolinite,and smectite(including irregular mixed-layers of illite-smectite(I/S)and chloritesmectite(C/S)).The clay mineral assemblages and proxies exhibit three stages of change,which are mainly controlled by the Zoige watershed range under different climate *** watershed was limited to the southeastern region with altitudes ranging from~3500 to~42.0 meters above sea level(m a.s.l.),and glacial-interglacial hydraulic erosion controlled the input of bedrock debris during 800-62. ka *** expanded to higher altitudes(~42.0 to~4700 m a.s.l.)due to stronger seasonal freezethaw weathering without significant glacial-interglacial variations under a cooling and drying climate during 62.-100 ka ***,it expanded to its highest altitudes of~4700 to~52.0 m *** of the watershed after 100 ka BP,and hydraulic erosion increased obviously under a warm climate of the interstadial MIS 3 on the *** watershed underwent two major expansions under different climatic conditions at~62. ka and 100 ka BP,with the wet/dry alternation became strong at~62. ka *** results reveal that long-term temperature changes and the wet/dry alternation at high altitudes controlled the watershed range and degree of the physical erosion,and that the indications of clay minerals should be carefully clarified before they are used as climate indicators,especi

关键词： Quaternary Zoige Basin Lacustrine sediments Paleoenvironment Weathering

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Shock Raman spectra and structural transformation of powdered TKX-50 by the plate impact experiments combined with real-time Raman detection

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Defence Technology（防务技术） 2024年第1期31卷 158-162页

作者： Xue Yang Qijun Liu Yundan Gan Lei Yang zhengtang Liu Fusheng Liu Bond and Band Engineering Group School of Physical Science and TechnologySouthwest Jiaotong UniversityChengdu 610031People's Republic of China Xi'an Modern Chemistry Research Institute Xi'an 710065People's Republic of China State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi'an 710072People's Republic of China

As an energetic material of great interest,the work capacity of dihydroxylammonium 5,5’-bistetrazole-1,1’-diolate(TKX-50)has been questioned *** some research groups have explored the reasons for the low working ability of TKX-50,the plane impact experiment on powdered TKX-50 is obviously closer to the practical application,and the conclusions based on this are more ***,we performed shock Hugoniot measurements of powdered TKX-50 between 5.65 and 16.2. *** plane impact experiments of powdered TKX-50 were carried out and the shocked Raman spectra were *** Raman spectroscopy analysis,a new peak of powdered TKX-50 was found between19.47 GPa and 2..96 GPa,which may be caused by decomposition/phase transition and was related with the low work capacity.

关键词： Powdered TKX-50 Hugoniot Raman Decomposition Phase transition

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Evolution of molecular structure of TATB under shock loading from transient Raman spectroscopic technique

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Defence Technology（防务技术） 2024年第3期33卷 613-620页

作者： Hongliang Kang Xue Yang Wenshuo Yuan Lei Yang Xinghan Li Fusheng Liu zhengtang Liu Qijun Liu Bond and Band Engineering Group School of Physical Science and TechnologySouthwest Jiaotong UniversityChengdu 610031China State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi'an 710072China

By combination of the transient Raman spectroscopic measurement and the density functional theoretical calculations,the structural evolution and stability of TATB under shock compression was *** to the improvement in synchronization control between two-stage light gas gun and the transient Raman spectra acquisition,as well as the sample preparation,the Raman peak of the N-O mode of TATB was firstly observed under shock pressure up to 13.6 GPa,noticeably higher than the upper limit of 8.5 GPa reported in available *** taking into account of the continuous shift of the main peak and other observed Raman peaks,we did not distinguish any structural transition or any new ***,both the present Raman spectra and the time-resolved radiation of TATB during shock loading showed that TATB exhibits higher chemical stability than previous *** reveal the detailed structural response and evolution of TATB under compression,the density functional theoretical calculations were conducted,and it was found that the pressure make N-O bond lengths shorter,nitro bond angles larger,and intermolecular and intra-molecular hydrogen bond interactions *** observed red shift of Raman peak was ascribed to the abnormal enhancement of H-bound effect on the scissor vibration mode of the nitro group.

关键词： TATB Raman spectra Structural evolution Shock loading

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A holistic perspective on Earth system science

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Science China Earth Sciences 2024年第10期67卷 3013-3040页

作者： Yongfei ZHENG zhengtang GUO Nianzhi JIAO Mu MU Shilong PIAO Suiyan FU Dinghui YANG Maoyan ZHU State Key Laboratory of Lithospheric and Environmental Coevolution School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China State Key Laboratory of Lithospheric and Environmental Coevolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China School of Ocean and Earth Sciences Xiamen UniversityXiamen 361102China Department of Atmospheric and Oceanic Sciences Fudan UniversityShanghai 200438China School of Environment Peking UniversityBeijing 100871China School of Earth and Space Sciences Peking UniversityBeijing 100871China Department of Mathematical Sciences Tsinghua UniversityBeijing 100084China Nanjing Institute of Geology and Palaeontology Chinese Academy of SciencesNanjing 210008China

Earth system can be categorized into three parts, solid Earth system, surface Earth system, and Sun-Earth space system. These three subsystems not only have mutual transmission and coupling relationships in both energy and matter but also involve multiple scales from microscopic to macroscopic. Earth system science is characterized by its globality and unity with a holistic view and a systematic view at multiple scales in both space and time. It focuses not only on the physical, chemical and biological interactions between various geospheres but also on the properties, behaviors, processes, and mechanisms of the entire Earth and its spheres. Although significant progress has been made in the study of internal disciplines of these three subsystems,there is still insufficient understanding of their overall behavior and interactions between individuals, thus facing challenges of different types and levels. The solid Earth system is composed of the crust, mantle, and core. Existing observational techniques struggle to penetrate deep into the mantle, making direct observation and data acquisition difficult;the extreme environments within Earth, such as high temperature, high pressure, and strong magnetic fields, also pose great challenges to observational equipment and scientific experiments. The surface Earth system is an open complex mega-system, in which there are complex interactions and feedback mechanisms among its geospheres(such as atmosphere, hydrosphere, biosphere, pedosphere and lithosphere), leading to difficulties in understanding of its overall behavior and long-term evolution. Biological activities have become increasingly significant in affecting the surface Earth system. The coupling between the internal and external Earth systems becomes more complex. Distinguishing and quantifying the impacts of Earth spherical interactions and biological activities on the surface Earth system is a major challenge. The Sun-Earth space system involves multiple physical

关键词： Earth's interior Earth's exterior Geospheres Energy exchange Material transfer

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Late Cenozoic uplift of the Liupan Mountains:Evidence from the Neogene loess deposits

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Science China Earth Sciences 2024年第5期67卷 1480-1488页

作者： Zhilin HE Yansong QIAO zhengtang GUO Chaoqin CHEN Long CHEN Yang FU Ye YANG Yanxia LIANG Xinru LIN Guoqiao XIAO Tao ZHAN Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Institute of Geomechanics Chinese Academy of Geological SciencesBeijing 100081China CAS Center for Excellence in Life and Paleoenvironment Beijing 100044China University of Chinese Academy of Sciences Beijing 100049China Institute of Ecological Geology Survey and Research of Heilongjiang Province Harbin 150030China School of Geography and Information Engineering China University of GeosciencesWuhan 430078China School of Earth Sciences China University of GeosciencesWuhan 430074China Natural Resources Survey Institute of Heilongjiang Province Harbin 150036China

The Liupan Mountains,one of the important mountain ranges in western China,are located on the boundary between the northeastern Tibetan Plateau and the Ordos *** uplift history of the Liupan Mountains remains *** deposits are good tracers of regional tectonic and geomorphic changes,because loess is sensitive to erosion and the formation and preservation of loess requires relatively flat highlands and relatively stable tectonic *** investigated the distribution of Neogene loess deposits on the western piedmont of the Liupan Mountains and examined a near-continuous loess section(Nanping section)on the piedmont alluvial *** of magnetic susceptibility stratigraphy with the QA-ⅠMiocene loess sequence dates this 56-m section covering the interval from~8.1 to 6.2.*** lower boundary age of this section,together with previously reported Zhuanglang red clay(sand-gravel layers with intercalated loess during~9–8 Ma and near-continuous loess during~8–4.8 Ma)and Chaona red clay(~8.1–2.58 Ma),indicates that the Liupan Mountains were uplifted in the late Miocene(~9–8 Ma)and basically formed by~8 Ma,attesting to no intense mountain building since that *** addition,based on the information from the Zhuanglang core and the QA-Ⅰsection,we infer that sizable parts of the Liupan Mountains were uplifted during the late Oligocene–early Miocene and did not experience intense uplift during~2.–9 Ma.

关键词： Liupan Mountains Mountain building Neogene Loess Chinese Loess Plateau Late Miocene Late Oligocene–early Miocene

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New dating indicates intermittent human occupation of the Nwya Devu Paleolithic site on the high-altitude central Tibetan Plateau during the past 45,000 years

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Science China Earth Sciences 2024年第2期67卷 531-551页

作者： Junyi GE Xiaoling ZHANG Shejiang WANG Linhui LI Wei HE Yingshuai JIN Peiqi ZhANG Bing XU Chenglong DENG John WOLSEN zhengtang GUO Xing GAO Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of SciencesBeijing 100044China University of the Chinese Academy of Sciences Beijing 100049China Tibetan Cultural Relics Conservation Institute Lhasa 850000China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of Sciences.Beijing 100029China State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China School of Anthropology University of ArizonaTucson85721USA

The timing and mechanisms of the human occupation of the demanding high-altitude Tibetan Plateau environment are of great ***,we report on our reinvestigations and dating of the Nwya Devu site,located nearly 4600 meters above sea level on the central Tibetan Plateau.A new microblade techno-complex was identified on a lower lake shore at this site,distinct from the previously reported blade tool *** two lithic assemblages were dated to 45.6±2.6 and10.3±0.5 ka using optically stimulated luminescence and accelerator mass spectrometry^(14)C *** represent,respectively,the earliest known Paleolithic and microlithic sites on the interior Tibetan Plateau,indicating multiple occupation episodes of hunter-gatherers during the past 45 *** studies reveal that relatively stable depositional conditions and a paleoenvironment characterized by a comparatively warm climate facilitated these multiple occupations at Nwya *** contemporaneous occurrence of the Upper Paleolithic blade technology on the Tibetan Plateau and most of Eurasia between 50 and 40 ka indicates rapid,large-scale dispersals of humans that profoundly affected human demography on a large *** new archaeological evidence and previously reported genetic data,we conclude that the Tibetan Plateau provided a relatively stable habitat for Upper Paleolithic hunter-gatherers,which may have contributed to the complex and multiple-origin gene pool of present-day Tibetans.

关键词： Tibetan Plateau Paleolithic Nwya Devu High-altitude adaptation Microblade industry Early Upper Paleolithic OSLdating AMS^(14)C dating

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Spatial continuous modeling of early Cenozoic carbon cycle and climate

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National Science Review 2024年第4期11卷 30-32页

作者： Yonggang Liu Jian Zhang Haoyue Zuo Zhilin He Jiaqi Guo Qifan Lin Haonan Yu Jiawenjing Lan Jing Han Zhihong Song Zihan Yin Liang Zhao Yongyun Hu zhengtang Guo Laboratory for Climate and Ocean-Atmosphere Studies Department of Atmospheric and Oceanic Sciences School of Physics Peking University Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of Sciences State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences

The partial pressure of atmospheric CO2.pCO2. is determined by the carbon cycle that involves climate, biogeochemistry, and plate tectonics. In this cycle,atmospheric CO2.s converted into organic carbon and carbonates by biological activities and silicate weathering, and buried as sediments. The sediments on the ocean floor are subducted into the Earth’s interior, and subsequently converted back into CO2.nd outgassed into the atmosphere.

关键词： ATMOSPHERIC CO2

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ASMT介导运动抗抑郁的炎症作用机制

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武汉体育学院学报 2024年第9期58卷 66-74页

作者：黄卓淳漆正堂刘微娜华东师范大学青少年健康评价与运动干预教育部重点实验室上海200241 华东师范大学体育与健康学院上海200241

目的:探究N-乙酰基-5-羟色胺-甲基转移酶(ASMT)基因敲除和运动对小鼠抑郁行为及神经炎症和肠道菌群的影响。方法:将6-7周龄雌性野生型小鼠和ASMT基因敲除小鼠随机分为安静组和运动组。12.的有氧跑台训练结束后,所有小鼠进行行为学测试... 详细信息

目的:探究N-乙酰基-5-羟色胺-甲基转移酶(ASMT)基因敲除和运动对小鼠抑郁行为及神经炎症和肠道菌群的影响。方法:将6-7周龄雌性野生型小鼠和ASMT基因敲除小鼠随机分为安静组和运动组。12.的有氧跑台训练结束后,所有小鼠进行行为学测试,训练期间收集小鼠粪便,然后将小鼠麻醉处死后取前额皮质和下丘脑。采用RT-PCR检测前额皮质促炎与抗炎因子和TLR4/NF-κB信号通路相关基因的表达水平;采用Western blotting检测下丘脑TLR4、p-IKBα、p65、p-p65和IL-Iβ的蛋白水平;采用16SrRNA基因测序检测小鼠运动干预第四周及第八周的粪便样本中菌群组成和丰度。结果:ASMT基因敲除会诱发小鼠的抑郁行为,运动可以有效缓解小鼠的抑郁行为。ASMT基因敲除后促炎因子水平和TLR4/NF-κB信号通路表达水平增加。肠道菌群16SrRNA基因测序结果显示ASMT基因敲除后α多样性及β多样性发生改变,细菌群落相对丰度有显著差异,持续的运动干预可以减少炎症从而调节肠道菌群稳态。结论:ASMT基因敲除可导致小鼠的抑郁行为,与TLR4/NF-κB信号通路影响神经炎症及肠道菌群有关,运动可以通过调节“微生物-肠-炎症-脑”轴改善肠道菌群紊乱进而缓解ASMT基因敲除导致的抑郁行为。

关键词：抑郁褪黑素 N-乙酰基-5-羟色胺-甲基转移酶(ASMT) 运动神经炎症肠道菌群

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导热吸波一体化材料的研究进展

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复合材料学报 2024年第5期41卷 2308-2320页

作者：苏蒸棠陈飞周致君陈刚蔡苇符春林重庆科技大学冶金与材料工程学院重庆401331 纳微复合材料与器件重庆市重点实验室重庆401331 重庆市鸿富诚电子新材料有限公司重庆402760

5G通信中电磁污染尤为严重,吸波材料可有效的吸收和衰减电磁波,将电磁能转换为热能的形式散失掉,已被广泛应用于航天航空、军事设施及电子通信等领域。然而,电子设备的小型化、集成化与高频化使电子设备无法及时将其产生的热能耗散掉,... 详细信息

5G通信中电磁污染尤为严重,吸波材料可有效的吸收和衰减电磁波,将电磁能转换为热能的形式散失掉,已被广泛应用于航天航空、军事设施及电子通信等领域。然而,电子设备的小型化、集成化与高频化使电子设备无法及时将其产生的热能耗散掉,从而影响设备的正常运行。因此,如何将导热材料高效的应用于电磁波吸收成为了当前吸波领域研究的重点和热点。基于此,本文综述了不同种类的导热材料在电磁波吸收中的应用及研究进展,首先按照组成成分介绍了导热材料的种类,并详细阐述了金属材料、陶瓷材料、碳材料及其复合物和导热高分子材料及其复合物的导热机制及不同导热材料在电磁波吸收中的作用机制与应用。最后对导热吸波一体化材料未来的研究方向及推广应用提出了见解。

关键词：导热材料电磁波吸收复合材料热导率吸波性能

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基于最优动态功率补偿的先进绝热压缩空气储能一次调频控制策略

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高电压技术 2024年第6期50卷 2433-2441,I0001页

作者：崔森陈来军陈思源孙正堂梅生伟清华大学电机工程与应用电子技术系北京100084

随着大规模新能源接入电网,新型电力系统“低惯量、弱支撑”特征凸显,电网频率调节资源日益稀缺,系统频率稳定问题愈发严峻。先进绝热压缩空气储能(advanced adiabatic compressed air energy storage,AA-CAES)具有容量大、寿命长等优... 详细信息

随着大规模新能源接入电网,新型电力系统“低惯量、弱支撑”特征凸显,电网频率调节资源日益稀缺,系统频率稳定问题愈发严峻。先进绝热压缩空气储能(advanced adiabatic compressed air energy storage,AA-CAES)具有容量大、寿命长等优势而受到广泛关注,但由于其储能和释能过程涉及气-热动态耦合过程,调频特性较为复杂,调频潜力还有待挖掘。因此,首先建立AA-CAES系统全工况动态仿真模型,进而基于期望频率动态曲线设计AA-CAES系统调频传递函数,优化目标传递函数关键参数,实现AA-CAES最小动态功率补偿下满足系统频率调节需求。最后通过仿真实验,验证了所提控制策略可优化AA-CAES调频容量的同时减小系统的稳态频率偏差与频率超调量,显著改善频率响应特性,为建设电网友好型AA-CAES电站提供技术支撑。

关键词：先进绝热压缩空气储能全工况动态建模功率补偿期望曲线频率调节调频容量

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