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Silurian integrative stratigraphy,biotas,and paleogeographical evolution of the Qinghai-Tibetan Plateau and its surrounding areas

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Science China Earth Sciences 2024年第4期67卷 1005-1035页

作者： Zhongyang CHEN Qing CHEN Guangxu WANG Xiang FANG Peng TANG Guanzhou YAN Wenwei YUAN Bing HUANG Xiaole zhang Kui YAN yuandong zhang Yi WANG State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyChinese Academy of SciencesNanjing 210008China University of Chinese Academy of Sciences Beijing 100049China

The Silurian palaeontology and stratigraphy of the Qinghai-Tibetan Plateau have been studied for more than100 *** the launch of the Second Tibetan Plateau Scientific Expedition and Research,it is necessary to update the summaries of the Silurian stratigraphy and fossil assemblages of the Qinghai-Tibetan Plateau and their correlation with its surrounding *** this study,we have selected 33 sections from the Qinghai-Tibetan Plateau and its surroundings areas,summarised the available data in terms of stratigraphic regionalisation,lithostratigraphy,chronostratigraphy,and biostratigraphy,and divided the study area into four stratigraphic provinces:the Xizang-Western Yunnan-Western Sichuan Province,the KunlunQilian Province,the South China Province,and the Tarim *** general,the Silurian strata in the Qinghai-Tibetan Plateau is more complete than those in other areas of *** studies of the vertebrate faunas,sporomorph assemblages,and brachiopod faunas of the study area indicate a closer geographical relationship between the South China,Tarim,and Indochina palaeoplates,than previously *** with the surrounding areas where Silurian strata have been extensively studied,the study of Silurian strata in the main part of the Qinghai-Tibetan Plateau is still in the preliminary *** the future,it is necessary to conduct research on the age,distribution,and resource potential of basal Silurian black shales to provide new directions for shale gas exploration and development in *** shallow marine strata of the middle to upper Silurian require further *** that the Silurian System in the Qinghai-Tibetan Plateau is more complete,it has the potential to supplement and improve the study of the carbon isotope stratigraphy of the Silurian in China.

关键词： Qinghai-Tibetan Plateau Silurian Stratigraphic regionalisation Lithostratigraphy Biostratigraphy Palaeogeographical evolution

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Ordovician integrative stratigraphy,biotas,and paleogeographical evolution of the Qinghai-Tibetan Plateau and its surrounding areas

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Science China Earth Sciences 2024年第4期67卷 971-1004页

作者： Xiang FANG Yong Yi ZHEN Guangxu WANG Xin WEI Zhongyang CHEN Yan LIANG Xuejin WU Wenjie LI Chao LI Renbin ZHAN yuandong zhang State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyChinese Academy of SciencesNanjing 210008China Geological Survey of New South Wales W.B.Clarke Geoscience CentreNSW 2753Australia University of Chinese Academy of Sciences Beijing 100049China

The Ordovician rocks on the Qinghai-Tibetan Plateau represent the oldest non-metamorphic strata,and are critical to understanding the history of regional geology and biotic evolution of the entire *** of Floian,Darriwilian,Sandbian,Katian and Hirnantian are represented in the plateau with a hiatus of variable duration occurring underneath the basal Ordovician across the *** stratigraphical regions,including the Himalaya,Gangdise-Zayu,Qiangtang-Qamdo,Songpan-Garze,and Karakoram-Kunlun-Altun,are differentiated for the Ordovician strata,which are correlated with their equivalents in the Sibumasu,Indochina,Qaidam-Qilian,Tarim-Tianshan,and the Yangtze(western margin)stratigraphical *** the QinghaiTibetan Plateau,graptolites,conodonts,and cephalopods are the most common and useful fossils for the Ordovician *** Ordovician biotas of the Qinghai-Tibetan Plateau bear some distinguishable palaeobiogeographical signatures,among which the cephalopods are characterized by the flourishing actinocerids of North China affinity in the Early-Middle Ordovician,and by the thriving lituitids and orthocerids of South China affinity in the Middle-Late *** occurrences and their palaeobiogeographical evolution provide critical evidence bearing on the reconstruction of the geological history of the Qinghai-Tibetan Plateau and surrounding terranes in northeastern *** stratigraphical successions of the Cambrian-Ordovician transition in the Himalaya and Lhasa and nearby Sibumasu terranes were significantly affected by the Kurgiakh Orogeny,which resulted in the extensive unconformity between the Ordovician and the underlying rocks in most areas of the Qinghai-Tibetan *** southern Xizang,a warm-water biota of Middle Ordovician age was recovered from oolitic limestones,suggesting a likely palaeogeographical location in low-latitudes near the *** the Himalaya and Sibumasu regions,the Upper Ordovician was typified by t

关键词： Ordovician Chronostratigraphy Lithostratigraphy Biostratigraphy Palaeobiogeography Qinghai-Tibetan Plateau

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中速磨煤机特征分类及劣化分析算法研究

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动力工程学报 2024年第8期44卷 1189-1195页

作者：张元东中国大唐集团科学技术研究总院有限公司华东电力试验研究院合肥230088

针对Simhash算法特征分类过程存在局部敏感hash、目前中速磨煤机劣化分析算法精准度不高的问题,提出一种中速磨煤机特征分类及劣化分析算法。首先,该算法基于Simhash机制结合余弦定理和矩阵相似性设计特征分类方法;然后,基于八邻域机制... 详细信息

针对Simhash算法特征分类过程存在局部敏感hash、目前中速磨煤机劣化分析算法精准度不高的问题,提出一种中速磨煤机特征分类及劣化分析算法。首先,该算法基于Simhash机制结合余弦定理和矩阵相似性设计特征分类方法;然后,基于八邻域机制结合自适应阈值设计中速磨煤机劣化分析判别规则。结果表明:本文算法使得中速磨煤机的特征参数辨识度、故障关联性以及健康状态预测精度得到了显著提升,且相较于目前主流机器学习算法,在均方根误差(RMSE)损失较小的情况下,计算效率显著提升,所提算法的准确性和健壮性更高。

关键词：中速磨煤机特征分类劣化分析 Simhash 自适应阈值

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Silurian integrative stratigraphy, biotas and palaeogeographical evolution of the Qinghai-Tibetan Plateau and its surrounding areas

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Science China Earth Sciences 2024年

作者： Zhongyang CHEN Qing CHEN Guangxu WANG Xiang FANG Peng TANG Guanzhou YAN Wenwei YUAN Bing HUANG Xiaole zhang Kui YAN yuandong zhang Yi WANG University of Chinese Academy of Sciences State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences

The Silurian palaeontology and stratigraphy of the Qinghai-Tibetan Plateau have been studied for more than100 years. With the launch of the Second Tibetan Plateau Scientific Expedition and Research, it is necessary to update the summaries of the Silurian stratigraphy and fossil assemblages of the Qinghai-Tibetan Plateau and their correlation with its surrounding areas. In this study, we have selected 33 sections from the Qinghai-Tibetan Plateau and its surroundings areas,summarised the available data in terms of stratigraphic regionalisation, lithostratigraphy, chronostratigraphy, and biostratigraphy,and divided the study area into four stratigraphic provinces:the Xizang-Western Yunnan-Western Sichuan Province, the KunlunQilian Province, the South China Province, and the Tarim Province. In general, the Silurian strata in the Qinghai-Tibetan Plateau is more complete than those in other areas of China. Palaeobiogeographical studies of the vertebrate faunas, sporomorph assemblages, and brachiopod faunas of the study area indicate a closer geographical relationship between the South China,Tarim, and Indochina palaeoplates, than previously considered. Compared with the surrounding areas where Silurian strata have been extensively studied, the study of Silurian strata in the main part of the Qinghai-Tibetan Plateau is still in the preliminary stage. In the future, it is necessary to conduct research on the age, distribution, and resource potential of basal Silurian black shales to provide new directions for shale gas exploration and development in China. The shallow marine strata of the middle to upper Silurian require further subdivision. Considering that the Silurian System in the Qinghai-Tibetan Plateau is more complete,it has the potential to supplement and improve the study of the carbon isotope stratigraphy of the Silurian in China.

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量化气候和土地利用变化对生态资产变化的相对贡献——以房山区为例

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生态学报 2024年第8期44卷 3213-3222页

作者：王鹤潭巩贺黄玫张远东孙玮顾峰雪中国农业科学院农业环境与可持续发展研究所农业农村部旱作节水农业重点实验室北京100081 中国科学院地理科学与资源研究所生态系统网络观测与模拟重点实验室北京100101 中国林业科学研究院森林生态环境与自然保护研究所国家林业和草原局森林生态环境重点实验室北京100091

生态资产与人类福祉密切相关,开展生态资产评估并定量区分气候和人类活动对生态资产变化的相对贡献,对于评估区域生态文明建设成效、生态补偿、干部离任的自然资产审计等均具有重要意义。在单位面积价值当量因子方法的基础上,重新定义... 详细信息

生态资产与人类福祉密切相关,开展生态资产评估并定量区分气候和人类活动对生态资产变化的相对贡献,对于评估区域生态文明建设成效、生态补偿、干部离任的自然资产审计等均具有重要意义。在单位面积价值当量因子方法的基础上,重新定义了标准生态服务价值当量因子,并构建了一个能够定量区分气候变化和土地利用变化对生态资产变化相对贡献的方法,以北京市房山区为例,分析了2000年至2019年房山区生态资产的变化,以及气候变化和土地利用变化对生态资产变化的相对贡献,结果表明:(1)房山区2019年生态资产总价值177.14亿元。森林、草地、农田和湿地的生态资产分别占生态资产总价值的82.33%、11.76%、5.25%和0.095%。(2)房山在2000—2019年期间,生态资产总价值增加了2.275亿元,气候变化使得房山区的生态资产总价值增加了2.689亿元,而土地利用变化使得生态资产总价值减少了0.414亿元。(3)房山区生态资产西高东低,其中霞云岭乡生态资产总价值最高;琉璃河镇的生态资产增加最多,而拱辰街道下降最显著。过去20年是房山区社会经济快速发展的时期,由于气候变化和生态保护与修复使得生态资产增加,抵消了由于建设用地扩张所带来的生态资产损失。

关键词：生态资产气候变化土地利用变化相对贡献

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Spatial and temporal patterns of the sensitivity of radial growth response by Picea schrenkiana to regional climate change in the Tianshan Mountains

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林业研究:英文版 2023年第6期34卷 1669-1681页

作者： Zhongtong Peng yuandong zhang Liangjun Zhu Mingming Guo Qingao Lu Kun Xu Hui Shao Qifeng Mo Shirong Liu Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration Ecology and Nature Conservation InstituteChinese Academy of ForestryBeijing 100091People’s Republic of China National Engineering Laboratory for Applied Technology of Forestry and Ecology in South China College of Life Science and TechnologyCentral South University of Forestry and TechnologyChangsha 410004People’s Republic of China College of Forestry Hebei Agricultural UniversityBaoding 071000People’s Republic of China Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm College of Forestry and Landscape ArchitectureSouth China Agricultural UniversityGuangzhou 510642People’s Republic of China

Climate change significantly impacts forest ecosystems in arid and semi-arid ***,spatiotemporal patterns of climate-sensitive changes in individual tree growth under increased climate warming and precipitation in north-west China is *** dendrochronological method was used to study climate response sensitivity of radial growth of Picea schrenkiana from 158 trees at six sites during *** results show that climate warming and increased precipitation significantly promoted the growth of *** response to temperature first increased,then ***,the response to increased precipitation and the self-calibrating Palmer Drought Severity Index(scPDSI)increased *** most areas of the Tianshan Mountains,the proportion of trees under increased precipitation and scPDSI positive response was relatively *** time,small-diameter trees were strongly affected by drought *** is predicted that under continuous warming and increased precipitation,trees in most areas of the Tianshan Mountains,especially those with small diameters,will be more affected by precipitation.

关键词： Regional climate change Picea schrenkiana Climate response sensitivity Spatiotemporal patterns Tianshan mountains

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Divergent responses of Picea crassifolia *** different forest patches to climate change in the northeastern Tibetan Plateau

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Forest Ecosystems 2023年第6期10卷 752-762页

作者： Zhongtong Peng Qifeng Mo Liangjun Zhu Qingao Lu Jiaqing Cai Mingming Guo Kun Xu yuandong zhang Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration Ecology and Nature Conservation InstituteChinese Academy of ForestryBeijing100091China Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm College of Forestry and Landscape ArchitectureSouth China Agricultural UniversityGuangzhou510642China National Engineering Laboratory for Applied Technology of Forestry&Ecology in South China College of Life Science and TechnologyCentral South University of Forestry and TechnologyChangsha410004China Swiss Federal Institute for Forest Snow and Landscape Research WSLBirmensdorf8903Switzerland Environment and Sustainability Institute University of ExeterPenryn CampusPenrynCornwallTR109FEUK College of Forestry Hebei Agricultural UniversityBaoding071000China

Global climate changes have significantly affected tree growth and forest structures and functions in some arid and semi-arid regions,which are becoming warmer and *** to natural factors such as climate and terrain,some tree species may form different forest patches at the edges of their distribution ***,how forest patches of various sizes respond to climate change is *** this study,we collected 203 tree cores from six different sizes of forest patches at the edge of the distribution area of Picea crassifolia *** the northeast Tibetan *** we used the dendrochronology method to study the response of tree growth and resilience in different forest patches to climate change from 1961 to *** simultaneously measured the contents of nonstructural carbohydrates(NSC),total nitrogen and total phosphorus of tree *** results showed that the growth of trees in small-and medium-size forest patches(0.8–18.6 ha)has increased *** early growing season(May–July)minimum temperature was the most important climate factor driving the growth of small-and medium-sized patch *** early growing season maximum temperature was the most important climate factor that inhibited the growth of trees in the largest patches(362.8 ha).The growth of individual trees in medium forest patches was better and the correlation with annual minimum temperature,maximum temperature,precipitation,actual evapotranspiration,and palmer drought severity index was *** higher NSC content,stronger photosynthesis,and higher nitrogen utilization efficiency in leaves might be one of the reasons for the better growth of trees in moderate forest *** extreme drought years,as the forest patch area increased,the overall trend of tree growth resistance showed a unimodal pattern,with the highest at a forest patch area of 7.1 ha,while the overall trend of tree growth recovery was ***,we should strengthen the management of trees in large

关键词： Climate change Picea crassifolia Kom Forest patches Tree growth Resilience

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High-frequency magnetic properties of biphase Ce_(2)Fe_(17)N_(3)/α-Fe microflakes with easy-plane anisotropy

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Journal of Rare Earths 2024年第1期42卷 110-115,I0004页

作者： Ke Wang Hang zhang yuandong Huang Zhibiao Xu Fashen Li Tao Wang Key Laboratory for Magnetism and Magnetic Materials of MOE Lanzhou UniversityLanzhou730000China Key Laboratory of Special Function Materials and Structure Design Ministry of EducationLanzhou UniversityLanzhou730000China

Soft magnetic composites(SMCs)are effective as magnetic powder cores in an *** to high saturation magnetization,large magnetocrystalline anisotropy and high operating frequency of M(metal)-RE(rear earth)soft magnetic composites,it is possible to miniaturize inductor cores by reducing total loss,especially eddy current loss and excess loss at high *** this article,the characteristics of Ce_(2)Fe_(17)N_(3)/α-Fe(CFN/F)loss per volume and effective permeability reaching a high frequency of 3 MHz are *** biphase CFN/F composite exhibits a high permeability of 16 at 70 MHz,which is two times greater than that of pure Ce_(2)Fe_(17)N_(3)(CFN)*** total loss is as low as 545 mW/cm^(3)at 3 MHz and 6 *** direct current(DC)-bias properties have a percent of permeability exceeding 65% at H=7960 A/*** phenomenon indicates that our material has a higher working frequency and lower core loss than other materials;the biphase CFN/F structure is a promising and efficient approach for developing the miniaturized radio frequency(RF)inductor core.

关键词： High frequency Soft magnetic composites Easy-plane anisotropy Permeability spectra Core loss Rare earths

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Nanoparticles with rough surface improve the therapeutic effect of photothermal immunotherapy against melanoma

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Acta Pharmaceutica Sinica B 2022年第6期12卷 2934-2949页

作者： Jiao Xue Yining Zhu Shuting Bai Chunting He Guangsheng Du yuandong zhang Yao Zhong Wenfei Chen Hairui Wang Xun Sun Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial TechnologyWest China School of PharmacySichuan UniversityChengdu 610041China

Photothermal therapy has been intensively investigated for treating cancer in recent ***,the long-term therapeutic outcome remains unsatisfying due to the frequently occurred metastasis and *** address this challenge,immunotherapy has been combined with photothermal therapy to activate anti-tumor immunity and relieve the immunosuppressive microenvironment within tumor ***,we engineered silica-based core-shell nanoparticles(JQ-1@PSNs-R),in which silica cores were coated with the photothermal agent polydopamine,and a bromodomain-containing protein 4(BRD4) inhibitor JQ-1 was loaded in the polydopamine layer to combine photo thermal and immune therapy for tumor ***,to improve the therapeutic effect,we increased the surface roughness of the nanoparticles by hydrofluoric acid(HF) etching during the fabrication process,and found that the internalization of JQ-1@PSNs-R was significantly improved,leading to a strengthened photothermal killing effect as well as the increased intracellular delivery of *** the animal studies,the multifunctional nanoparticles with rough surfaces effectively eradicated melanoma via photothermal therapy,successfully activated tumor-specific immune responses against residual tumor cells,and further prevented tumor metastasis and *** results indicated that JQ-1@PSNs-R could serve as an innovative and effective strategy for combined cancer therapy.

关键词： Photothermal therapy Immunotherapy Rough surface Polydopamine-coated silica nanoparticles JQ-1 Melanoma

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Diversity history of Ordovician graptolites and its relationship with environmental change

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Science China Earth Sciences 2008年第2期51卷 161-171页

作者： zhang yuandong Chen Xu LPS Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China

Statistical analysis based on global data indicated that the planktonic graptolites presented a distinguished pattern from that of benthic communities during the great Ordovician biodiversification. The graptolites started to diversify from the beginning of Ordovician and reached an acme in the early Middle Ordovician, but subsequently underwent a steady decline to the end of Ordovician. During the Ordovician, many clades of the graptolites made their originations, flourishing and replacements. However, in different regions and distinct environments across the world, graptolites may presumably display distinct patterns of radiation and evolution, a hypothesis to be tested. Herein a study of the graptolite diversity in the Early to Middle Ordovician in the Upper Yangtze Region (Platform) and Jiangnan Region (Slope), South China, is conducted. The results indicate that graptolites underwent a remarkable increase in both regions, but with distinct magnitude, scope, process and patterns. The diversification of graptolites in the Upper Yangtze Region, though less prominent, is divided into four stages and includes two peaks. In the Jiangnan Region, the graptolite diversification is far more prominent and includes three stages and one peak. Based on the distinct diversity histories and composition of graptolites in the two representative regions, a 'deep-water origin and shallow-water dispersal' model is proposed for the Ordovician graptolite faunas. According to the model, the major graptolite faunas of Ordovician originated in the deep-water region on the continental slope, the source of the graptolite novelties, and subsequently spread into shallow-water region on the shelf. Besides, we also conduct a comparison study of the Ordovician graptolite diversity in South China and other major regions. The results display that the graptolites diversified globally in the Early and Middle Ordovician. At the beginning of Ordovician, graptolites underwent a significant ecological

关键词： South China Ordovician graptolite diversity deep-water origin sea-level change

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