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Chinese Science Bulletin 1998年第1期43卷 72-75页

作者： chen jun\+1, ji {3.\+1, su {3..+2 and lu {3.\+3.. department of earth sciences, nanjing university, {13. 210093..China 2. Center of Material Analysis, nanjing university, {13. 210093..China 3..Xi’an Laboratory of Loess and Qu department of earth sciences Nanjing University Nanjing China Center of Material Analysis Nanjing University Nanjing China Xi’an Laboratory of Loess and Quaternary Geology Chinese Academy of Sciences Xi’an China

Mn 2+ EPR intensity recorded in the Chinese loess_paleosol sequence shows close correlation with magnetic susceptibility and Sr content as well as the oscillation of paleoclimate. Thus Mn 2+ EPR signal can serve as an... 详细信息

关键词： paleomonsoon loess paleosol EPR signal of Mn 2+

Recent advances in chemical protein synthesis:method developments and biological applications

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Science China Chemistry 2024年第4期67卷 1060-1096页

作者： suwei Dong ji-Shen Zheng Yiming Li Huan Wang Gong chen Yongxiang chen Gemin Fang jun Guo Chunmao He Honggang Hu Xuechen Li Yanmei Li Zigang Li Man Pan Shan Tang Changlin Tian Ping Wang Bian Wu Chuanliu Wu {3. Zhao Lei Liu State Key Laboratory of Natural and Biomimetic Drugs and School of Pharmaceutical SciencesPeking UniversityBeijing 100191China Division of Life sciences and Medicine University of Science and Technology of ChinaHefei 230027China School of Food and Biological Engineering Engineering Research Center of Bio-processMinistry of EducationHefei University of TechnologyHefei 230009China School of Chemistry and Chemical Engineering Nanjing UniversityNanjing 210023China State Key Laboratory of Elemento-Organic Chemistry Nankai UniversityTianjin 300071China department of Chemistry Tsinghua UniversityBeijing 100084China Institute of Health sciences Anhui UniversityHefei 230601China College of Chemistry Central China Normal UniversityWuhan 430079China School of Chemistry and Chemical Engineering South China University of TechnologyGuangzhou 510640China School of Medicine or Institute of Translational Medicine Shanghai UniversityShanghai 200444China department of Chemistry The University of Hong KongHong Kong 999077China Shenzhen Graduate School Peking UniversityShenzhen 518055China School of Chemistry and Chemical Engineering Shanghai Jiao Tong UniversityShanghai 200240China School of Life sciences University of Science and Technology of ChinaHefei 230026China department of Chemical Biology Shanghai Jiao Tong UniversityShanghai 200240China Institute of Microbiology Chinese Academy of SciencesBeijing 100101China department of Chemistry Xiamen UniversityXiamen 361005China School of Pharmaceutical Science Guangzhou Medical UniversityGuangzhou 511436China

The central dogma of modern biology underscores the pivotal roles proteins play in diverse biological processes,the study of which necessitates advanced methods to produce proteins with precision and *** protein synthesis,a powerful approach utilizing chemical reactions for the de novo construction of structurally accurate proteins,has emerged as a transformative tool for studying proteins and generating protein derivatives/mimics inaccessible by natural biological machinery,including post-translationally modified proteins,proteins comprised of unnatural amino acids,as well as mirror-image *** review summarizes recent strides in synthetic method developments for chemical protein synthesis,including innovative techniques in solid-phase peptide synthesis,the challenges presented by difficult sequences in either synthesis or folding and the exploration of novel ligation reactions using both chemical and enzymatic ***,the review also delves into newly developed protocols for site-selective protein modifications and the generation of stapled or macrocyclized peptides/miniproteins,highlighting the power of chemical methods to make structurally diverse *** applications of synthetic proteins in investigating post-translational modifications(phosphorylation,lipidation,glycosylation,ubiquitination,etc.),mirror-image biological processes and drug development are further ***,these topics provide a comprehensive overview of the current landscape of chemical protein synthesis.

关键词： chemical protein synthesis solid-phase peptide synthesis ligation reactions post-translational modifications mirror-image proteins peptide drugs

Evolution of chlorite composition in the Paleogene prototype basin of jiyang Depression, Shandong, China, and its implication for paleogeothermal gradient

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Science China earth sciences 2007年第11期50卷 1645-1654页

作者： ZHAO Ming1, chen XiaoMing1, ji junfeng1, ZHANG Zhe1 & ZHANG Yun2 1 State Key Laboratory for Mineral Deposits Research, {3. of {3..sciences, nanjing university, nanjing 210093..China 2 jiangsu survey Institute of Engineering and Physics, nanjing 210008, China State Key Laboratory for Mineral Deposits Research Department of Earth Sciences Nanjing University Nanjing China jiangsu survey Institute of Engineering and Physics Nanjing China

The Dongying Basin, Huimin Basin, and Zhanhua Basin constitute the jiyang Depression in Shandong Province. They are major oil and gas exploring districts within the depression. Through reconstructions of the paleotemperature of the three basins facilitated with the chlorite geothermometry, the thermal history of the Paleogene prototype basin in jiyang Depression and its geologic significance were explored. This study reveals that the Si^(4+) component in chlorites reduces gradually as its buried depth increases, while the AI~Ⅳ component increases accordingly. The chlorite type changes from silicon-rich diabantite to silicon-poor ferroamesite and prochlorite. The prochlorite in this district only appears in the deep buried depth, high temperature, and relatively old stratigraphies; while the diabantite appears in the shallower buried, low temperature, and newly formed strata; the ferroamesite exists in the conditions between prochlorite and diabantite formation. The diagenetic temperatures of the chlorites in these Paleogene basins are 171 — 23.. for the Dongying Basin, 160—202℃ for the Huimin Basin, and 13..180℃ for the Zhanhua Basin. The differences of the chlorite diagenetic temperatures in the three basins were controlled by the duration time of the structural depressing processes. Higher temperature indicates longer depression time. The relationship between the chlorite diagenetic temperature and its buried depth indicates that the average paleogeothermal gradient is about 3..3../km in the Paleogene prototype basin of jiyang Depression. It was higher than the present geothermal gradient (29—3../km). This phenomenon was attributed to the evolution of the structural dynamics in the depression basin.

关键词： Paleogene,jiyang depression,chlorite component,chlorite geothermometry,paleotemperature,paleogeothermal gradient

DEVELOPMENT OF A NEW TIME SCALE FOR THE QUATERNARY CLIMATE IN THE CHINESE LOESS PLATEAU BASED ON Rb CONCENTRATIONS

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南京大学学报(自然科学) 1999年第6期 3-5页

作者： chen Yang chen jun {3. jun Feng (department of {3. sciences, nanjing university, 210093..nanjing, PRC)

ＬｏｅｓｓｄｅｐｏｓｉｔｓａｎｄｉｎｔｅｒｃａｌａｔｅｄｐａｌｅｏｓｏｌｓｏｎｔｈｅＬｏｅｓｓＰｌａｔｅａｕｉｎｃｅｎｔｒａｌＣｈｉｎａｓｐａｎｎｅｄｔｈｅｐａｓｔ2.5ｍ.ｙ.ａｎｄｐｒｏｖｉｄｅｄａｃｏｎｔｉｎｕｏｕ... 详细信息

ＬｏｅｓｓｄｅｐｏｓｉｔｓａｎｄｉｎｔｅｒｃａｌａｔｅｄｐａｌｅｏｓｏｌｓｏｎｔｈｅＬｏｅｓｓＰｌａｔｅａｕｉｎｃｅｎｔｒａｌＣｈｉｎａｓｐａｎｎｅｄｔｈｅｐａｓｔ2.5ｍ.ｙ.ａｎｄｐｒｏｖｉｄｅｄａｃｏｎｔｉｎｕｏｕｓｐｒｏｘｙｒｅｃｏｒｄｏｆｖａｒ?..

关键词： Quaternary time scale loess paleosol sequence Rb concentrations

Variation of Zr/Rb ratios on the Loess Plateau of Central China during the last 13..00 years and its implications for winter monsoon

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Chinese Science Bulletin 2002年第15期47卷 1298-1302页

作者： LIU Lianwen chen jun chen Yang {3. {3..lu {3. Institute of surficial Geochemistry State Key Laboratory of Mineral Deposit ResearchDepartment of Earth SciencesNanjing UniversityNanjing 210093China Institute of earth Environment Chinese Academy of Sciences

To find a new index of winter monsoon without effects of chemical weathering and pedogenesis is an important task in loess research. Chemical analysis of five grain size fractions (i.e. >3..m, 3..20μm, 20-8μm, 8-2μm and 1LL1 and L1LL2) from Huanxian and Xifeng sections, reflecting that Zr/Rb ratios increase when grain size is coarser. Due to immobility of the two elements during the postdepositional process, Zr/Rb ratios can eliminate the effect of weathering and pedogenesis and serve as an excellent proxy on winter monsoon variation. The Zr/Rb ratio curves of the Huanxian, Xifeng and luochuan sections during the last 13..00 years show that the winter monsoon strength was very weak during MIS 3..which corresponded to the intensity during MIS 5.

关键词： loess index of winter monsoon Zr/Rb ratios grain size.

A lunar time scale from the perspective of the Moon’s dynamic evolution

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Science China earth sciences 2024年第1期67卷 234-251页

作者： Dijun GUO jianzhong LIU James WHEAD Fuqin ZHANG Zongcheng LING Shengbo chen jianping chen Xiaozhong DING jinzhu ji Ziyuan OUYANG State Key Laboratory of Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China Center for lunar and Planetary sciences Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China department of earth Environmental and Planetary SciencesBrown UniversityProvidence RI 02912USA Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100029China Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space SciencesShandong UniversityWeihai 264209China College of Geoexploration Science and Technology Jilin UniversityChangchun 130026China School of earth sciences and Resources China University of GeosciencesBeijing 100083China Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China School of Resources and Environmental Engineering Inner Mongolia University of TechnologyHohhot 010051China Center for Excellence in Comparative Planetology Chinese Academy of SciencesHefei 230026China

A geologic time scale is a chronological system that separates the geological strata of a planetary body into different units in temporal sequence and shows its progressive *** time scale of the Moon was established a half-century ago during the telescopic-early Apollo exploration era,using data with limited spatial coverage and *** past decades have seen a wide array of studies,which have significantly extended our understanding of global lunar geologic *** on a comprehensive review of lunar evolution with respect to the dynamical changes,we propose two major updates to the current lunar time scale paradigm to include the evolution of both endogenic and exogenic dynamic forces now known to have influenced early lunar ***,based on the temporal interplay of exogenic and endogenic processes in altering the Moon,we defined three Eon/Eonothem-level units to represent three dynamical evolutionary ***,the pre-Nectarian System is redefined and divided as the magma ocean-era Magma-oceanian System and the following Aitkenian System beginning with the South Pole-Aitken *** ejecta of this basin,Das Formation,was deposited on the primordial lunar crust as the oldest stratum produced from exogenic *** updated lunar time scale,facilitated by the post-Apollo exploration and research advances,provides an integrated framework to depict the evolution of the Moon and has important implications for the geologic study of other terrestrial planets.

关键词： The Moon Geologic time scale Evolution history Endogenic process Exogenic process

晚始新世-早渐新世渭河盆地古气候变化的碳酸盐记录

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第四纪研究 2024年第2期44卷 309-324页

作者：陈璇璇鹿化煜吕恒志王逸超王可欣程鉴如季峻峰林春明南京大学地理与海洋科学学院江苏南京210023 西安交通大学人居环境与建筑工程学院陕西西安712000 南京大学地球科学与工程学院江苏南京210023

晚始新世-早渐新世转变期(约3..Ma, EOT)温度降低是新生代显著气候事件之一,对亚洲环境演变有深刻影响。本研究基于渭河盆地厚度为413..5 m的支家沟剖面3..89~3..51 Ma时段的河湖相沉积,获得高分辨率总碳酸盐、方解石含量变化序列,结合... 详细信息

晚始新世-早渐新世转变期(约3..Ma, EOT)温度降低是新生代显著气候事件之一,对亚洲环境演变有深刻影响。本研究基于渭河盆地厚度为413..5 m的支家沟剖面3..89~3..51 Ma时段的河湖相沉积,获得高分辨率总碳酸盐、方解石含量变化序列,结合薄片及扫描电镜分析,尝试建立晚始新世-早渐新世渭河盆地气候和环境演变时间序列,探讨EOT期间渭河盆地古气候对全球温度变化的响应。镜下岩石薄片鉴定显示,沉积物粒度变化与岩相变化对应较为一致。3..89~3..89 Ma,高含量的总碳酸盐、方解石指示气候较为温暖干旱,沉积序列指示从滨湖相向湖泊三角洲相过渡;3..89~3..09 Ma期间,低含量的总碳酸盐、方解石指示气候偏凉且相对湿润,沉积环境为湖泊三角洲向滨浅湖过渡,水位逐渐上升;3..09~3..51 Ma,总碳酸盐、方解石含量变化与地层岩性变化有较好的一致性,此时沉积相为滨湖相,湖泊水位可能高于3..89~3..89 Ma,但低于3..89~3..09 Ma。结合全球温度变化序列,本研究认为渭河盆地始新世晚期-渐新世早期湿度变化可能受全球温度驱动的蒸发量控制,但明确的驱动机制有待进一步研究。

关键词：渭河盆地碳酸盐方解石始新世-渐新世转型暖期古气候

Rb and Sr Geochemical Characterization of the Chinese Loess Stratigraphy and Its Implications for Palaeomonsoon Climate

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Acta Geologica Sinica(English Edition) 2000年第2期74卷 279-288页

作者： chen jun WANG Yongjin chen Yang LIU Lianwen ji {3..lu {3. department of earth sciences Nanjing UniversityNanjing 210093 department of Geography Nanjing Normal UniversityNanjing 210097 department of earth sciences Nanjing UniversityNanjing 210093 Xi’an State Key Laboratory of Loess and Quaternary Geology Chinese Academy of SciencesXi’an 710061

Concentrations and distributions of Rb and Sr in loess and palaeosol samples from the luochuan profile have been studied, in grain-size fractions and chemical forms. Results show that Rb is quite rich in the fraction of less than 2 μm, and exits only in the residual phase, while Sr is distributed in sand and silt fractions, occurring in the residual and carbonate phases. Therefore, variations of the concentrations of Rb and Sr in loess and palaeosols are closely related not only to dustfall compositions depending on winter monsoon wind strength but also to summer monsoon-induced pedogenic intensity. This indicates that variations of Rb/Sr ratio in Chinese loess sequences represent cyclic alternations of East Asian summer and winter monsoon climates on the orbital time-scale. Variations in Sr concentrations along the sequence bear a high similarity to the oxygen isotope record of the deep sea sediments over the past 2.5 Ma, whereas variations in Rb concentrations are in good agreement with the record of magnetic susceptibility determined with the duplicated samples from the same profile. This suggests that (1) the high-latitude ice volume is responsible for East Asian monsoon variations and (2) the signal of magnetic susceptibility depends dominantly on pedogenesis in Chinese loess sequences.

关键词： Rb and Sr geochemical characterization Rb/Sr ratios loess sequence palaeomonsoon climate Loess Plateau

Sahara’s surface transformation forced an abrupt hydroclimate decline and Neolithic culture transition in northern China

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The Innovation 2024年第1期5卷 70-79页

作者： Yandong Hou Hao Long sumiko Tsukamoto Zhengyao lu {3.e chen Daniel EIbarra Toru Tamura Qiong Zhang Weiyi sun {3.ngran Zhang Lei Gao Manfred Frechen {3. Shen State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and LimnologyChinese Academy of Sciences(NIGLAS)Nanjing 210008China Leibniz Institute for Applied Geophysics(LIAG) Department of Geochronology30655 HannoverGermany department of Physical Geography and Ecosystem Science Lund University22100 LundSweden Key Laboratory of Western China’s Environmental Systems(Ministry of Education) College of Earth and Environmental SciencesLanzhou UniversityLanzhou 730000China College of Atmospheric sciences Lanzhou UniversityLanzhou 730000China Institute at Brown for Environment and Society and department of earth Environmentaland Planetary SciencesBrown UniversityProvidenceRI 02912USA Geological survey of Japan National Institute of Advanced Industrial Science and TechnologyTsukubaIbaraki 305-8567Japan Graduate School of Frontier sciences University of TokyoKashiwaChiba 277-8561Japan department of Physical Geography and Bolin Centre for Climate Research Stockholm University10691 StockholmSweden School of Geography Nanjing Normal UniversityJiangsu Centre for Collaborative Innovation in Geographical Information Resource Development and ApplicationKey Laboratory of Virtual Geographic EnvironmentMinistry of Education of ChinaNanjing 210023China School of Geography and Ocean Science Nanjing UniversityNanjing 210023China

The remote forcing from land surface changes in the Sahara is hypothesized to play a pivotal role in modulating the intensity of the East Asian summer monsoon(EASM)through ocean-atmospheric *** modulation has far-reaching consequences,particularly in facilitating societal shifts documented in northern ***,we present a well-dated lake-level record from the Daihai Lake Basin in northern China,providing quantitative assessments of Holocene monsoonal precipitation and the consequent migrations of the northern boundary of the *** reconstruction,informed by a water-and-energy balance model,indicates that annual precipitation reached700 mm during 8–5 ka,followed by a rapid decline to tween 5 and 4 *** shift coherently aligns with a signi550 mm be-ficant3.. km northwestward movement of the EASM northern boundary during the Middle Holocene(MH),in contrast to its current *** findings underscore that these changes cannot be entirely attributed to orbital forcing,as corroborated by simulation *** model simulations deployed in our study suggest that the presence of the Green Sahara during the MH significantly strengthened the EASM and led to a northward shift of the monsoon rainfall ***,the Sahara’s reversion to a desert landscape in the late Holocene was accompanied by a corresponding southward retraction of monsoon *** dramatic hydroclimate changes during5–4 ka likely triggered or at least contributed to a shift in Neolithic cultures and societal transformation in northern *** decreasing agricultural productivity,communities transitioned from millet farming to a mixed rainfed agriculture and animal husbandry ***,our findings elucidate not only the variability of the EASM but also the profound implications of a remote forcing,such as surface transformations of the Sahara,on climatic changes and cultural evolution in northern China.

关键词： Holocene monsoon abrupt

Geochemical characterization of major elements in desert sediments and implications for the Chinese loess source

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Science China earth sciences 2019年第9期62卷 1428-1440页

作者： Wancang ZHAO Lianwen LIU jun chen junfeng {3. Chongqing Key Laboratory of Karst Environment School of Geographical Sciences Southwest University Chongqing 400715 China Ministry of Education Key Laboratory of surficial Geochemistry School of Earth Sciences and Engineering Nanjing University Nanjing 210023 China

Mineral dust released from the desert is one of the important components of atmospheric aerosols. Arid and semi-arid deserts, sandy lands in northern China and their adjacent Gobi Desert lands in northern China and neighboring Mongolia(hereinafter referred to as Gobi) are potential sources of mineral dust in Asia. However, there is currently a lack of systematic studies on the characteristics of major elements in the potential mineral dust source area. This study investigates the major elements of 3.. surficial sand samples in the stabilized and semi-stabilized dune fields from 12 deserts/sandy land and Gobi in northern China and southern Mongolian Gobi and compiles published data. We identify four regions with distinct geochemical characteristics:(1) Taklimakan, Kumtag and Qaidam deserts in western China;(2) Badain Jaran, Tengger, Hobq, and Mu Us deserts in the central and western regions of northern China;(3..Hu{3.n Buir, Onqin Daga and Horqin sandy lands in northeast China;and(4) Gobi and Gurbantunggut deserts. The spatial distributions of the SiO2 and CaO contents in Chinese deserts are highly variable. The average content of SiO2 generally reflects an increasing trend from west to east, while the average content of CaO shows a decreasing trend from west to east. We demonstrate that the spatial variation of major elements is likely controlled by two key scenarios: the composition of source rocks and the mineral maturity caused by the supply of fresh materials. The SiO2/(Al2O3..2O+Na2O) ratio of desert sediments is relatively lower in western China and may be caused by high ferricmagnesia and high carbonate minerals;this ratio is relatively higher in the northeast sandy lands and may be linked to a lack of fresh material supply and the presence of high K-feldspar minerals in source rocks. The deserts can be further distinguished by ternary diagrams with SiO2/10-CaO-Al2O3..K2O+Na2O)-CaO-Fe2O3..nd CaO-Na2O-K2O. The comparison of major elements between desert sedimen

关键词： Desert Loess Major elements Eolian Dust Carbonate