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Changes of grain size from peat profile in eastern mountainous area over past 2000 years,Jilin Province,Northeast China

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Global Geology 2024年第3期27卷 132-144页

作者： ZHANG Xinrong WANG Jiayu ping shuaifei LI Yaran College of Earth Sciences Jilin UniversityChangchun 130061China Key Laboratory of Mineral Resources Evaluation in Northeast Asia Ministry of Natural ResourcesJilin UniversityChangchun 130061China Key Laboratory for Oil Shale and Coexisting Minerals Jilin UniversityChangchun 130061China Standing Committee of the People's Congress of Ninghe District Tianjin CityTianjin 301574China

Plenty of high-resolution paleoclimate investigations of the last thousand years were carried out to potentially predict future climate *** ombrotrophic peatland is one of the best recorders for high-resolution paleoclimate studies in the forest *** size analysis was carried out on ombrotrophic peat profile in the eastern mountainous region of Jilin Province,Northeast *** peat profile lasts the past 2000 a by four radiocarbon(AMS14C)*** results showed that the inorganic minerals in the peat profile are mainly silt,with some contribution from clay and a minor amount of sand,which are mainly due to wind dust and suspended *** paleoclimate stages are found in this peat profile by phytolith analysis,peat cellulose isotope research and historical documents:ca.45–1550 AD,relatively cold period;ca.1550 AD–present,relatively warm *** finding is important for the initial study of paleoclimatic changes over the last 2000 a in the mountainous area of eastern mountainous area,Jilin Province,Northeast China.

关键词： peat sediments grain size analysis paleoclimate

Changes of grain size from peat profile in eastern mountainous area over past 2000 years, Jilin Province, NE China

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Global Geology 2024年

作者： Zhang Xinrong Wang Jiayu ping shuaifei Li Yaran College of Earth Science Jilin University Key Laboratory of Mineral Resources Evaluation in Northeast Asia Ministry of Natural Resources Key-Laboratory for Oil Shale and Coexisting Minerals Jilin University Ninghe District of Banqiao Town People's Government

Plenty of high-resolution paleoclimate investigations of the last thousand years were carried out to potentially predict future climate changes. Mountainous ombrotrophic peatland is one of the best recorders for high-resolution paleoclimate studies in the forest area. Grain size analysis was carried out on ombrotrophic peat profile in the eastern mountainous region of Jilin Province, NE China. The peat profile lasts the past 2 000 a by four radiocarbon (AMS 14C) ages. The results showed that the inorganic minerals in the peat profile are mainly silt, with some contribution from clay and a minor amount of sand, which are mainly due to wind dust and suspended transportation. Two paleoclimate stages are found in this peat profile by phytolith analysis, peat cellulose isotope research and historical documents,ca. 45–1550 AD., a relative cold period; ca. 1550 AD-present, warm. This finding is important for the initialstudyofpaleoclimaticchangesoverthelast2000ainthemountainousareaofeatern mountainous area, Jilin Province, NE China.

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松嫩平原南缘现代沉积物磁化率、粒度、色度特征及古气候环境意义

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吉林大学学报（地球科学版） 2020年第2期50卷 465-479页

作者：张新荣平帅飞焦洁钰刘恩豪吉林大学地球科学学院长春130061 东北亚生物演化与环境教育部重点实验室(吉林大学) 长春130026 吉林省油页岩与共生能源矿产重点实验室长春130061

深入了解松嫩平原第四纪古气候演化过程,对本区黑土退化的气候影响因素研究有重要理论意义。选择松嫩平原南缘大黑山地垒长春-四平段郭家(GJ)、湾沟(WG)、平安屯(PA)、腰分水岭旁(YP)、西地(XD)、胡家甸(H)、肖家(XJ)7个现代沉积剖面进... 详细信息

深入了解松嫩平原第四纪古气候演化过程,对本区黑土退化的气候影响因素研究有重要理论意义。选择松嫩平原南缘大黑山地垒长春-四平段郭家(GJ)、湾沟(WG)、平安屯(PA)、腰分水岭旁(YP)、西地(XD)、胡家甸(H)、肖家(XJ)7个现代沉积剖面进行磁化率、粒度和色度分析。结果显示:各剖面沉积物磁化率多表现为干燥时期较大、湿润时期较小、寒冷阶段较大、温暖适宜阶段较小的特点。颜色对磁化率影响较大,不同颜色砂或砂质黏土的磁化率从大到小依次为红褐色→浅黄色或灰绿色→灰黑色。碳酸盐岩或灰岩物源的存在,使沉积物色度和磁化率之间的关系相对复杂。磁化率会随沉积物粒度增大而增大,冻融风化和降雨增多导致沉积物粒度增大,使磁化率升高;但温暖适宜时期,磁化率受物源供给量的减小而减小。磁化率、粒度和色度三指标综合反映出研究区早更新世寒冷干燥→中更新世冷湿-暖湿-冷湿→晚更新世寒冷较湿润的古气候环境演化过程。

关键词：磁化率粒度色度古气候环境松嫩平原南缘

植硅体记录的敦化北部山地近2 ka泥炭沼泽演化气候背景

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吉林大学学报（地球科学版） 2020年第1期50卷 170-184页

作者：杜玉张新荣平帅飞焦洁钰马春梅吉林大学地球科学学院长春130061 吉林大学东北亚生物演化与环境教育部重点实验室长春130026 吉林省油页岩与共生能源矿产重点实验室长春130061 南京大学地理与海洋科学学院南京210023

对敦化北部山地205 cm深泥炭剖面中的植硅体进行提取、鉴定和分析,结合AMS14C测年,重建研究区近2 ka的古气候环境过程,探讨其变化规律及影响因素。植硅体组合、有序聚类和植硅体指数变化趋势显示,研究区泥炭沼泽经历了4个显著阶段:即45... 详细信息

对敦化北部山地205 cm深泥炭剖面中的植硅体进行提取、鉴定和分析,结合AMS14C测年,重建研究区近2 ka的古气候环境过程,探讨其变化规律及影响因素。植硅体组合、有序聚类和植硅体指数变化趋势显示,研究区泥炭沼泽经历了4个显著阶段:即45—680 A.D.暖湿阶段;680—1340 A.D.温暖偏干阶段;1340—1870 A.D.由干转湿的寒冷阶段;1870—2017 A.D.转暖、干湿波动阶段。其中,680—1225 A.D.对应中世纪暖期(MWP),1340—1870 A.D.对应小冰期(LIA)。在此气候变化背景下,泥炭沼泽发展经历了由缓慢逐渐加快的过程。对比太阳辐射和太阳活动的变化、石笋δ18O序列、重建的东北地区古温度以及Niňo3.4重建曲线,泥炭剖面的植硅体分析显示MWP和LIA期间的古气候过程受到太阳活动、太阳辐射、季风环流和ENSO(El Niňo-Southern Oscillation)的控制。

关键词：植硅体泥炭演化气候变迁区域差异敦化山地

中国东北依兰盆地始新世气候演化及湿度降低对冷却事件的指示

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世界地质 2022年第2期41卷 256-271页

作者：张新荣刘晓奇方石平帅飞张世锋王晓杨吉林大学地球科学学院长春130061 自然资源部东北亚矿产资源评价重点实验室长春130061 吉林省油页岩与共生能源矿产重点实验室长春130061 天津市宁河区板桥镇人民政府天津301574 黑龙江龙煤地质勘探有限公司黑龙江佳木斯154000 大庆油田第六采油厂黑龙江大庆163000

利用时频时序分析对依兰盆地始新世连续沉积物的烧失量数据进行旋回划分,再利用皮尔逊相关分析、降噪滤波和统计学方法分析有机质和碳酸盐的含量特征和变化规律。在依兰盆地始新世中识别出湿热、半湿较热、半干较热、干冷、半干较冷和... 详细信息

利用时频时序分析对依兰盆地始新世连续沉积物的烧失量数据进行旋回划分,再利用皮尔逊相关分析、降噪滤波和统计学方法分析有机质和碳酸盐的含量特征和变化规律。在依兰盆地始新世中识别出湿热、半湿较热、半干较热、干冷、半干较冷和半湿较冷6种气候状态。认为其温度湿度的中长期变化趋势是先升高,在巴顿阶末期温度湿度达到整个始新世最高,之后逐渐降低,在晚始新世早期达到最低,之后回升,又小幅下降。在短期气候变化过程中,温度湿度从同步平衡态向下一个同步平衡态过渡的过程中,温度保持不变,湿度持续下降,是冷却即将出现的重要标志。依兰盆地始新世中长期温度变化与东北地区一致,滞后于深海同位素揭示的温度变化。

关键词：依兰盆地始新世气候演化烧失量温度湿度

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依兰盆地始新世沉积碎屑约束的古气候演化

世界地质 2023年第2期42卷 284-296页

作者：张新荣霍元勃谢玉祥高晓岩平帅飞张世锋吉林大学地球科学学院长春130061 自然资源部东北亚矿产资源评价重点实验室长春130061 吉林省油页岩与共生能源矿产重点实验室长春130061 中煤能源黑龙江煤化工有限公司哈尔滨154054 天津市宁河区板桥镇人民政府天津301574 黑龙江龙煤地质勘探有限公司黑龙江佳木斯154000

为补充和印证其他气候代用指标揭示的东北地区始新世古气候的变化规律和变化细节,利用时频、时序分析以及降噪滤波等方法分析依兰始新世沉积碎屑组分中长石/石英和单晶石英/多晶石英的旋回性及细节特征揭示其气候变化过程。结果表明:依... 详细信息

为补充和印证其他气候代用指标揭示的东北地区始新世古气候的变化规律和变化细节,利用时频、时序分析以及降噪滤波等方法分析依兰始新世沉积碎屑组分中长石/石英和单晶石英/多晶石英的旋回性及细节特征揭示其气候变化过程。结果表明:依兰地区始新世存在暖湿、较暖湿、较干冷和干冷4种气候状态;伊普利斯期气候由初期的干冷逐渐变得暖湿,在卢泰特期开始达到始新世最暖湿的状态,卢泰特期晚期向干冷变化,到巴顿期早期达到最干冷状态,之后气候波动回暖;长石/石英和单晶石英/多晶石英所指示的结果与其他气候代用指标推断的变化趋势存在较好的一致性;长石/石英和单晶石英/多晶石英整体呈镜像关系,镜像程度越高,推断结果越同步,则推断结果越可信;其中长石/石英整体上对暖湿过程敏感,单晶石英/多晶石英对干冷过程敏感。

关键词：长石/石英单晶石英/多晶石英风化作用古气候始新世依兰地区

A survey on user-centric cell-free massive MIMO systems

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Digital Communications and Networks 2022年第5期8卷 695-719页

作者： shuaifei Chen Jiayi Zhang Jing Zhang Emil Björnson Bo Ai School of Electronic and Information Engineering Beijing Jiaotong UniversityBeijing100044China Frontiers Science Center for Smart High-speed Railway System Beijing Jiaotong UniversityBeijing100044China Department of Computer Science KTH Royal Institute of TechnologySE-16440KistaSweden Department of Electrical Engineering(ISY) Linköping UniversitySE-58183LinköpingSweden State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong UniversityBeijing100044China

The mobile data traffic has been exponentially growing during the last several *** was enabled by the densification of the network infrastructure in terms of increased cell density(i.e.,Ultra-Dense Network(UDN))and/or the increased number of active antennas per Access Point(AP)(i.e.,massive Multiple-Input Multiple-Output(mMIMO)).However,neither UDN nor mMIMO will meet the increasing demand for the data rate of the Sixth Generation(6G)wireless communications due to the inter-cell interference and large quality-of-service ***-Free(CF)mMIMO,which combines the best aspects of UDN and mMIMO,is viewed as a key solution to this *** such systems,each User Equipment(UE)is served by a preferred set of surrounding APs *** this paper,we provide a survey of the state-of-the-art literature on CF *** a starting point,the significance and the basic properties of CF mMIMO are *** then present the canonical framework to discuss the essential details(i.e.,transmission procedure and mathematical system model).Next,we provide a deep look at the resource allocation and signal processing problems related to CF mMIMO and survey the up-to-date schemes and *** that,we discuss the practical issues in implementing CF mMIMO and point out the potential future ***,we conclude this paper with a summary of the key lessons learned in this field.

关键词： 6G network User-centric cell-free network Massive multiple-input multiple-output

Dimensionality-driven metal to Mott insulator transition in two-dimensional 1T-TaSe2

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National Science Review 2024年第3期11卷 108-118页

作者： Ning Tian Zhe Huang Bo Gyu Jang shuaifei Guo Ya-Jun Yan Jingjing Gao Yijun Yu Jinwoong Hwang Cenyao Tang Meixiao Wang Xuan Luo Yu ping Sun Zhongkai Liu Dong-Lai Feng Xianhui Chen Sung-Kwan Mo Minjae Kim Young-Woo Son Dawei Shen Wei Ruan Yuanbo Zhang State Key Laboratory of Surface Physics New Cornerstone Science Laboratory and Department of PhysicsFudan University Shanghai Qi Zhi Institute Shanghai Research Center for Quantum Sciences Institute for Nanoelectronic Devices and Quantum Computing Fudan University Zhangjiang Fudan International Innovation Center Fudan University State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information Technology(SIMIT)Chinese Academy of Sciences School of Physical Science and Technology ShanghaiTech University Korea Institute for Advanced Study School of Emerging Technology and Department of Physics University of Science and Technology of China Advanced Light Source Lawrence Berkeley National Laboratory ShanghaiTech Laboratory for Topological Physics Key Laboratory of Materials Physics Institute of Solid State Physics Hefei Institutes of Physical ScienceChinese Academy of Sciences High Magnetic Field Laboratory Hefei Institutes of Physical Science Chinese Academy of Sciences Collaborative Innovation Centre of Advanced Microstructures Nanjing University Department of Physics University of Science and Technology of China and Key Laboratory of Strongly Coupled Quantum Matter Physics Chinese Academy of Sciences National Synchrotron Radiation Laboratory University of Science and Technology of China

Two-dimensional materials represent a major frontier for research into exotic many-body quantum phenomena. In the extreme two-dimensional limit, electron-electron interaction often dominates over other electronic energy scales, leading to strongly correlated effects such as quantum spin liquid and unconventional *** dominance is conventionally attributed to the lack of electron screening in the third dimension. Here, we discover an intriguing metal to Mott insulator transition in 1T-TaSe2that defies conventional wisdom. Specifically, we find that dimensionality crossover, instead of reduced screening, drives the transition in atomically thin 1T-TaSe2. A dispersive band crossing the Fermi level is found to be responsible for the bulk metallicity in the material. Reducing the dimensionality,however, effectively quenches the kinetic energy of these initially itinerant electrons, and drives the material into a Mott insulating *** dimensionality-driven metal to Mott insulator transition resolves the long-standing dichotomy between metallic bulk and insulating surface of 1T-TaSe2. Our work further reveals a new pathway for modulating two-dimensional materials that enables exploring strongly correlated systems across uncharted parameter space.

关键词： two-dimensional materials 1T-TaSe2 dimensionality crossover metal to Mott insulator transition

Pentacam三维眼前节分析仪与iTrace视觉分析仪测量近视眼Kappa角的一致性分析

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眼科学报 2023年第6期38卷 449-453页

作者：张晓山王萍李帅飞王莺华厦眼科集团医院佛山华厦眼科医院佛山528000 郑州爱尔眼科医院郑州450000 广州中医药大学金沙洲医院广州510168

目的:比较Pentacam三维眼前节分析仪与iTrace视觉分析仪在暗室环境中检测近视眼Kappa角的一致性。方法:采用回顾性研究,对近视门诊的86例志愿者共172眼使用iTrace视觉分析仪和Pentacam三维眼前节分析仪,分别测量其Kappa角,收集所测数据... 详细信息

目的:比较Pentacam三维眼前节分析仪与iTrace视觉分析仪在暗室环境中检测近视眼Kappa角的一致性。方法:采用回顾性研究,对近视门诊的86例志愿者共172眼使用iTrace视觉分析仪和Pentacam三维眼前节分析仪,分别测量其Kappa角,收集所测数据采用SPSS软件进行一致性分析。结果:Pentacam三维眼前节分析仪与iTrace视觉分析仪的Kappa角测量结果中,横坐标X值、纵坐标Y值和方位角度值比较差异有统计学意义(P0.05)。结论:Pentacam三维眼前节分析仪与iTrace视觉分析仪在近视患者Kappa角测量结果一致性存在差异,临床上应谨慎替换使用。

关键词： iTrace视觉分析仪 Pentacam三维眼前节分析仪 Kappa角一致性分析