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Petrography,geochemistry and provenance of the sediments of the Early Cretaceous Yanguoxia Formation,Lanzhou-Minhe Basin,Northwest China

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Journal of Mountain Science 2018年第9期15卷 2068-2088页

作者： du ding-ding MUGHAL Muhammad Saleem ZHANG Cheng-jun School of Earth Sciences and Mineral Resources Lanzhou UniversityLanzhou 730000China Key Laboratory of Western China's Mineral Resources of Gansu Province Lanzhou 730000China Institute of Geology University of Azad Jammu and KashmirMuzaffarabad 13100Pakistan

Lanzhou-Minhe Basin is situated on the middle Qilian orogenic belt. Yanguoxia Formation contains abundance of maroon siltstones, mudstones and red sandstones of the lake facies. These sedimentary rocks recorded the process of the tectonic uplift of Qilian Mountains during the Early Cretaceous. We discovered plentiful dinosaur footprints, worm burrows, bird footprints, worm tracks-trails, ripple marks and cross lamination in the Yanguoxia site. Integrated petrographic studies classified sandstones of Yanguoxia Formation as feldspathic litharenite. All plots in the QFL(Q or Qt, total quartz; F, feldspar; L, lithic grains) and Qm FLt(Qm, monocrystalline quartz; Lt, lithic grains plus polycrystalline quartz) diagrams fall in the recycled orogen provenance field and quartzose recycled field, respectively, implying the source occurred the tectonic activity. Furthermore, geochemical study indicates that the Yanguoxia standstone was formed in an unstable continental setting due to the northwards movement of Indian Plate triggered the collision between the Qilian fold belt and the Qinlingfold belt. These sediments were derived from a mixed source and then deposited in the Lanzhou-Minhe Basin. Most of the felsic components were derived from the granitoid rocks of the Qilian Mountains due to the rapid and intense uplift during the Early Cretaceous while the mafic components were contributed by the basic and ultrabasic rocks of the rapidly rising ophiolite in the Qilian Mountain area. Bivariant log-log plot of Qp/(F+L)(Qp, polycrystalline quartz) against Q/(F+L) shows that Yanguoxia Formation was deposited in the semihumid and semi-arid. Moreover, the pollen also exhibits that the environmental condition during the deposition of Yanguoxia Formation was warm and wet, which affirm such environment was benefit to dinosaur survival. Geochemical study also infers that the Yanguoxia Formation was deposited under the oxidizing condition in a shallow marine environment. The minerals id

关键词： Lanzhou-Minhe Basin YanguoxiaFormation Petrography Geochemistry Provenanceand weathering Teetonism and environment

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Variations in rare earth elements with environmental factors in lake surface sediments from 17 lakes in western China

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Journal of Mountain Science 2021年第7期18卷 1811-1822页

作者： du ding-ding CHEN Liu-qin BAI Yong-hui HU Hai-ping School of Earth Sciences East China University of TechnologyNanchang 330013China State Key Laboratory of Nuclear Resources and Environment Nanchang 330013China School of Earth Sciences Lanzhou UniversityLanzhou 730000China

Numerous lakes in western China are excellent sites for understanding environmental ***,what dominates rare earth element(REE) variations are still under debate in the lake environmental *** this study,we selected 28 surface sediment samples from 17 lakes(*** lakes,small water bodies,etc.) in the QinghaiTibet Plateau and Xinjiang *** samples were analyzed to reveal the behavior of the REEs and major *** REE patterns are characterized by light rare earth element(LREE) enrichment,weak Ce anomaly(0.84-0.98,0.94 on average) and negative Eu anomaly(0.53-1.00,0.67 on average).The homogeneous REE patterns may reflect similar REE of the source ***,the REE abundances showed some significant *** this study,water chemistry data analyses inferred that the highly REE values appear possibly in the saltwater lake,and also related to carbonate mineral,whereas p H played a minor role in REE *** large-scale lakes(*** Bosten and Lake Ulungur),the results showed that the relatively larger REE values are in the margins of ***,lower REE contents are towards the central *** study suggested that five major factors control the REE contents:(1) The REE tends to increase with the increase of the weathering intensity.(2) Likewise,heavy mineral(***,anatase,zircon,etc.) are probably primary in these sediments because they are highly enriched in the REE.(3) The contribution of Fe-Mn oxides is significant in sediments because their concentrations highly correlate with the REE.(4) The carbonate mineral(mainly calcite) played a significant role on the REE values in the lakes because the REEs are incorporated into the carbonate minerals generating the low REE concentrations.(5) Major element analysis,mineral analysis,and grain-size data analysis showed that the REE distribution is chiefly influenced by finer grain-size component of lake sediments due to the decreasing propor

关键词： Western China Lake surface sediments Rare earth elements Environmental factors

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Influences of environmental factors on the modern 14C reservoir effects in Qinghai-Tibet Plateau lakes

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Journal of Mountain Science 2021年第12期18卷 3179-3189页

作者： du ding-ding LI Zhi-wen HU Hai-ping BAI Yong-hui LI Wen MUGHAL Muhammad Saleem QIAN Hai-Yan East China University of Technology Key Laboratory for Digital Land and Resources of Jiangxi ProvinceNanchang 330013China Lanzhou University School of Earth SciencesLanzhou 730000China School of Environmental and Chemical Engineering Foshan UniversityFoshan 528000China Institute of Geology University of Azad Jammu and KashmirMuzaffarabad 13100Pakistan

The establishment of reliable age in the lake sediment profile mainly depends on the AMS 14C dating ***,the presence of the 14C lake reservoir effects(LREs)restricted for using radiocarbon dating in lake sediment,especially in dry and cold areas with a scarce plant cover in the Qinghai-Tibet ***,the discussion of influence factors of LREs is *** paper selected 15 lakes(17 sediment and 3 plant samples)in the Qinghai-Tibet Plateau to examine the distribution characteristics of the modern LREs and their main influencing *** our study area,14 lakes were all affected by the *** minimum 14C year is 5900 a BP towards the deep water area,whereas the maximum 14C year is up to 7185 a BP in the margins of Lake *** maximum 14C year is up to 7750 a BP,and the minimum 14C year is present-day carbon in the 15 *** further study indicated that the LRE differences in individual lake are mostly owing to the contribution of exogenous *** results displayed that the LREs tended to increase with the increase of the salinity,moreover,the LREs of saltwater lakes or salt lakes were significantly larger than freshwater lakes due to the possible supply of old total dissolved inorganic carbon with a long residence time in the ***,the contribution of calcite played a significant role on the ***,the LREs differences are affected by the source of organic *** lake with groundwater supply shows large LRE due to likely being influenced by crustal and ancient CO_(2) uprising.

关键词： Qinghai-Tibet Plateau Hydro-chemistry indexes Lake surface sediments Lake reservoir effects

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Lithological and environmental controls on large tafoni along conglomerate cliffs in subtropic humid Danxiashan UNESCO Global Geopark

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Journal of Mountain Science 2021年第5期18卷 1131-1143页

作者： CHEN Xin CHEN Liu-qin ZHANG Yan-hong du ding-ding HU Hai-ping LIU Dong-xing LI Wen-zhuo State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China School of Earth Sciences East China University of TechnologyNanchang 330013China School of Water Resources and Environmental Engineering East China University of TechnologyNanchang 330013China

Tafoni are a type of cavernous weathering features widespread in different climate zones around the world,but their origin has not been fully *** attention was paid on tafoni in *** UNESCO Global Geopark,located within the subtropic humid region of South China,has a landscape of large tafoni that occur on cliffs of red *** the Dinosaur Rock and Pagoda Peak of the geopark were selected to investigate the formation mechanisms of tafoni in *** the field investigation,the size,rock hardness,and the external and internal meteorology of tafoni were measured and *** texture and composition of rock samples were observed,and the ion chromatography experiments were performed as *** show that tafoni have well ellipsoidal *** of the conglomerates are largely sub-rounded and poorly sorted,and the cement is dominantly composed of calcite and iron *** hardness of the lips is almost equal to that of the columns,and both are slightly higher than the *** with the external intense environmental changes,the interior of the tafoni is characterized by smaller temperature and relative humidity ranges and windless ***,the porous and permeable conglomerates provide favorable lithology for tafoni development,and the micro-environment within the caverns is conducive to improving water utilization efficiency and enhancing salt *** salts mainly consist of sulfates and nitrates,which might be derived from frequent raining,water evaporation and red beds as ***,tafoni are the result of the synergistic effects by multiple factors,rather than a single mechanism.

关键词： Tafoni Conglomerate Salt weathering Danxia landscape Mt.Danxiashan

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Detrital apatite fission track constraints on Cenozoic tectonic evolution of the northeastern Qinghai-Tibet Plateau, China： Evidence from Cenozoic strata in Lulehe section, Northern Qaidam Basin

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Journal of Mountain Science 2018年第3期15卷 532-547页

作者： du ding-ding ZHANG Cheng-jun MUGHAL Muhammad Saleem WANG Xiao-yu BLAISE Dembele GAO Jun-ping MA Yuan LUO Xin-rong School of Earth Sciences and Mineral Resources Lanzhou University Lanzhou 730000 China Key Laboratory of Western China's Mineral Resources of Gansu Prouince Lanzhou 730000 China Institute of Geology University of Azad Jammu and Kashmir Muzaffarabad 13100 Pakistan

The Northern Qaidam Basin is located at the northeastern part of the Qinghai-Tibetan Plateau. It contains very thick Cenozoic terrestrial clastic sediments, which records the formation of the northern Qaidam Basin due to compressional deformation during the Indo-Asian collision. In this paper, we used detrital apatite fission-track thermochronology, including 4 sandstones and 2 conglomerates samples from the Lulehe section, to reveal the Cenozoic evolution of the northern Qaidam Basin. Fission-track dating indicated the source region of the Lulehe section has experiencedimportant cooling and uplifting in the Late Cretaceous(at ~85.1 Ma and ~65 Ma) and the Eocene(~52 Ma), respectively. The AFT age distribution on the section suggested that the provenance of Lulehe section sediments were mainly derived from the south Qilian Shan(Qilian Mountains) and Altun Shan(Altun Mountains), and two significantly provenance changes may occur at 43.4-46.1 Ma and ~37.8 Ma, respectively. The results may have strong constrains on the Cenozoic deformation and tectonic evolution of the northern Qaidam Basin and Qinghai-Tibet Plateau.

关键词： Northern Qaidam Basin Apatite Fission-Track Tectonic evolution Provenance analysis

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East Asian summer monsoon changes in subtropical China since late Pleistocene:Evidence from the Ailuropoda-Stegodon fauna

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Journal of Mountain Science 2022年第2期19卷 418-432页

作者： LI Zhi-wen SUN Li LI Bao-sheng WANG Feng-nian du ding-ding SONG You-gui ZHANG Hui-Juan CHEN Liu-qin XU Dan School of Environmental and Chemical Engineering Foshan UniversityFoshan 528225China State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China School of Geography South China Normal UniversityGuangzhou 510631China School of Geography and Tourism Huizhou UniversityHuizhou 516007China State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi'an 710061China

Previous studies on the amplitude of East Asian summer monsoon(EASM)changes mainly focused on northern China(represented by the Loess Plateau).However,a rare investigation centered on the subtropical zone of southern China,where the important route for EASM moved northward or southward,especially addressing a lack of the research on *** Ailuropoda-Stegodon fauna is a representative mammal fauna in southern China since the late *** indicates the southern mid-subtropicaltropical forest environment with tropical climate characteristics,and its southward or northward movements in the subtropical zone imply the changes of EASM *** on previous research,combined with the species characteristics and distribution range of the Ailuropoda-Stegodon fauna with tropical animals during the marine isotope stage 5(MIS5),MIS3,MIS2,and MIS1 Megathermal periods,this paper mainly investigates its evolution and the fluctuations of *** conclusions include:(1)The distribution geometric centers in the MIS5,MIS3,MIS2,and MIS1 Megathermal periods are(26°14′N,111°22′E),(24°35′N,107°30′E),(22°48′N,112°01′E),and(26°19′N,112°25′E),respectively.(2)Compared with the MIS5 period,the EASM of the MIS3 and MIS2 moved 180 km and 380 km southwards,and that of the MIS1 Megathermal period moved about 10 km *** EASM movement indicated by the fauna migration happened synchronous with the climate records of stalagmites in subtropical China,the sporopollen from eastern China,and oxygen isotopes from Sulu *** also correspond to the peaks and valleys of the total solar radiation at 35°N in the winter *** suggests that the migrations of the Ailuropoda-Stegodon fauna are consistent with the changes of the global climate,and the driving force is mainly from the changes of total solar radiation at 35°N in the winter half-year.

关键词： Late Pleistocene to Holocene Subtropical China the Ailuropoda-Stegodon fauna Tropical animals migration East Asian summer monsoon changes The total solar radiation

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数字信号发生器的设计

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河北农业大学学报 2009年第1期32卷 117-121页

作者：杜丁丁马坤茹保定广播电视大学河北保定071000 河北科技大学建筑工程学院河北石家庄050018

信号发生器是一种常用的仪器,能够实现各种波形,不同频率的输出,电子测试系统的重要部件。本研究的数字信号发生器是基于直接数字合成即DDS技术设计的,采用VHDL与C语言相结合的方法,通过查找存储于ROM查找表中的各种标准波形数据,产生... 详细信息

信号发生器是一种常用的仪器,能够实现各种波形,不同频率的输出,电子测试系统的重要部件。本研究的数字信号发生器是基于直接数字合成即DDS技术设计的,采用VHDL与C语言相结合的方法,通过查找存储于ROM查找表中的各种标准波形数据,产生频率可调并且高精度的正弦波、方波、锯齿波等常用信号,并且可以通过修改表中的数据,实现任意信号发生器。

关键词：信号发生器直接数字合成 VHDL 查找表

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青藏高原中部色林错湖泊沉积物色度反映末次冰盛期以来区域古气候演化

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干旱区地理 2019年第3期42卷 551-558页

作者：杜丁丁 Muhammad Saleem Mughal Dembele Blaise 张成君东华理工大学地球科学学院江西南昌330013 兰州大学地质科学与矿产资源学院甘肃省西部矿产资源重点实验室甘肃兰州730000

色林错湖位于青藏高原内部,是西藏第一大咸水内陆湖。研究区剖面选自色林错第三湖泊阶地,利用常用气候替代指标色度,结合粒度、碳酸盐含量[CaCO3(%)]、矿物分析和全有机质(TOC)等进行对比分析,同时采用14C测年方法对剖面进行准确的年代... 详细信息

色林错湖位于青藏高原内部,是西藏第一大咸水内陆湖。研究区剖面选自色林错第三湖泊阶地,利用常用气候替代指标色度,结合粒度、碳酸盐含量[CaCO3(%)]、矿物分析和全有机质(TOC)等进行对比分析,同时采用14C测年方法对剖面进行准确的年代划分,初步探讨了末次冰盛期以来色林错湖泊沉积物色度增强机制的差异性。研究表明:a*、b*与中粗粒砂、磁化率具有较好的相关性;亮度L*与CaCO3(%)具较好相关性;因而沉积物色度变化可反应区域古气候变化。同时对湖泊沉积物矿物分析发现,影响色度变化的制色矿物主要是针铁矿,且以还原环境为主。红度a*高值与亮度L*低值对应气候暖湿气候环境,沉积物粒度较粗,碳酸盐含量低,有机质含量高,磁化率较高值;反之,红度a*低值,L*高值,粒度较细,碳酸盐含量高,有机质含量低,磁化率低值,对应干冷气候。在17.4~15.5 cal ka BP阶段,对应干冷的气候特点;在15.5~10.4 cal ka BP阶段,对应温暖湿润的气候;在10.4~5.2 cal ka BP阶段,整体属于温暖湿润的气候特点;其中,在9.7~9.4 cal ka BP和8.75~8.5 cal ka BP为两个重要的冷事件,属于干湿的气候特点;在5.2~1.2 cal ka BP阶段,反映了干冷的气候特征;在4.3~4.0 cal ka BP,3.3~3.0 cal ka BP和2.4~1.75 cal ka BP,反映了干旱温暖的气候特点;在1.2 cal ka BP以后,色林错湖湖水迅速下降。

关键词：色度粒度古气候环境色林错湖泊

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An Efficient Boron Source Activation Strategy for the Low‑Temperature Synthesis of Boron Nitride Nanotubes

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Nano-Micro Letters 2025年第1期17卷 548-558页

作者： Ying Wang Kai Zhang Liping ding Liyun Wu Songfeng E Qian He Nanyang Wang Hui Zuo Zhengyang Zhou Feng ding Yue Hu Jin Zhang Yagang Yao National Laboratory of Solid State Microstructures College of Engineering and Applied SciencesJiangsu Key Laboratory of Artificial Functional Materialsand Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093People’s Republic of China School of Electronic Information and Artificial Intelligence Shaanxi University of Science&TechnologyXian 710000People’s Republic of China College of Bioresources Chemical and Materials Engineering Shaanxi University of Science&TechnologyXian 710000People’s Republic of China Key Laboratory of Carbon Materials of Zhejiang Province College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325000People’s Republic of China Shenzhen Institutes of Advanced Technology Chinese Academy of SciencesShenzhen 518000People’s Republic of China College of Chemical and Molecular Engineering Peking UniversityBeijing 100871People’s Republic of China

Lowering the synthesis temperature of boron nitride nanotubes(BNNTs)is crucial for their *** primary reason for adopting a high temperature is to enable the effective activation of highmelting-point solid *** this study,we developed a novel approach for efficiently activating boron by introducing alkali metal compounds into the conventional MgO–B *** approach can be adopted to form various low-melting-point AM–Mg–B–O growth *** growth systems have improved catalytic capability and reactivity even under low-temperature conditions,facilitating the synthesis of BNNTs at temperatures as low as 850℃.In addition,molecular dynamics simulations based on density functional theory theoretically demonstrate that the systems maintain a liquid state at low temperatures and interact with N atoms to form BN *** findings offer novel insights into the design of boron activation and are expected to facilitate research on the low-temperature synthesis of BNNTs.

关键词： Boron nitride nanotubes Low-temperature Boron activation Density functional theory

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Subretinal fibrosis secondary to neovascular age-related macular degeneration:mechanisms and potential therapeutic targets

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Neural Regeneration Research 2025年第2期20卷 378-393页

作者： Jingxiang Zhang Xia Sheng Quanju ding Yujun Wang Jiwei Zhao Jingfa Zhang Department of Ophthalmology People’s Hospital of Huangdao DistrictQingdaoShandong ProvinceChina Department of Urology People’s Hospital of Huangdao DistrictQingdaoShandong ProvinceChina Department of Ophthalmology Shanghai General Hospital(Shanghai First People’s Hospital)Shanghai Jiao Tong University School of MedicineShanghaiChina National Clinical Research Center for Eye Diseases Shanghai Key Laboratory of Ocular Fundus DiseasesShanghai Engineering Center for Visual Science and PhotomedicineShanghai Engineering Center for Precise Diagnosis and Treatment of Eye DiseasesShanghaiChina

Subretinal fibrosis is the end-stage sequelae of neovascular age-related macular *** causes local damage to photoreceptors,retinal pigment epithelium,and choroidal vessels,which leads to permanent central vision loss of patients with neovascular age-related macular *** pathogenesis of subretinal fibrosis is complex,and the underlying mechanisms are largely ***,there are no effective treatment options.A thorough understanding of the pathogenesis of subretinal fibrosis and its related mechanisms is important to elucidate its complications and explore potential *** current article reviews several aspects of subretinal fibrosis,including the current understanding on the relationship between neovascular age-related macular degeneration and subretinal fibrosis;multimodal imaging techniques for subretinal fibrosis;animal models for studying subretinal fibrosis;cellular and non-cellular constituents of subretinal fibrosis;pathophysiological mechanisms involved in subretinal fibrosis,such as aging,infiltration of macrophages,different sources of mesenchymal transition to myofibroblast,and activation of complement system and immune cells;and several key molecules and signaling pathways participating in the pathogenesis of subretinal fibrosis,such as vascular endothelial growth factor,connective tissue growth factor,fibroblast growth factor 2,platelet-derived growth factor and platelet-derived growth factor receptor-β,transforming growth factor-βsignaling pathway,Wnt signaling pathway,and the axis of heat shock protein 70-Toll-like receptors 2/*** review will improve the understanding of the pathogenesis of subretinal fibrosis,allow the discovery of molecular targets,and explore potential treatments for the management of subretinal fibrosis.

关键词： choroidal neovascularization epithelial-mesenchymal transition mesenchymal transition myofibroblast neovascular age-related macular degeneration submacular fibrosis subretinal fibrosis therapeutic targets transforming growth factor-β vascular endothelial growth factor

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