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Paleoclimatic application of spectral parameters to the eolian red clay of the Jianzha Basin,northeastern margin of the Tibetan Plateau

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Science China Earth Sciences 2024年第6期67卷 1952-1966页

作者： Chaofeng FU Ju’e TIAN Xinwen XU Yougui song Jun ZUO Feng WANG Lin CHEN Pengfei LI Xiaoke QIANG The School of Earth Science and Resources Chang’an UniversityXi’an 710054China State Key Laboratory of Loess and Quaternary Geology Institute of Earth and EnvironmentCASXi’an 710061China College of Urban and Environmental Science Northwest UniversityXi’an 710069China CAS Center for Excellence in Quaternary Science and Global change Xi’an 710061China

Reflectance spectroscopy is rapid,inexpensive,and non-destructive and can provide important information about the mineralogy of rocks and *** measured the reflectance spectroscopy of Miocene red clay deposits on the northeastern margin of the Tibetan Plateau,with the aim of developing a rapid methodology for detecting paleoclimatic *** obtained visible/near-infrared(VNIR)and short-wave infrared(SWIR)spectroscopy data from the red clay in the Jianzha Basin,and analyzed their relationship with independent paleoclimatic records,including mineral contents and environmental magnetic *** results show that the VNIR parameters,including D500,D900,R500,and R900(where D and R represent the depth and reflectance of the absorption peaks around 500 and 900 nm,respectively)are temperature-sensitive and correlated with the magnetic susceptibility,frequency-dependent magnetic susceptibility,and the marine δ^(18)O *** results of frequency-domain analysis of the VNIR parameters show that they reflect climate change on orbital *** parameters,such as AS1400,D1400/D1900 and D1900(where AS represents the asymmetry of the absorption peaks around1400 nm),are correlated with the illite and montmorillonite content,and they are sensitive to the weathering *** spectral parameters of the eolian red clay in the Jianzha Basin reflect regional climatic changes caused by the uplift of the Tibetan Plateau at~8.5 Ma and global climatic cooling at~7.2 Ma,and thus they are applicable as both regional and global paleoenvironmental indicators.

关键词： Visible/near-infrared spectroscopy Short-wave infrared spectroscopy Paleoclimatic indicators Red clay Tibetan Plateau

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帕金森病脑PET葡萄糖代谢模式研究进展

中国医学影像学杂志 2024年第3期32卷 289-293页

作者：杨畅宋天彬张春卢洁首都医科大学宣武医院放射与核医学科北京100053 磁共振成像脑信息学北京市重点实验室北京100053

帕金森病是常见的神经退行性疾病,严重影响患者的生存质量,其早期精准诊断是目前医学一大难题。PET可无创、在体监测帕金森病患者早期脑病理生理改变,具有良好的临床应用价值。^(18)F-FDG PET脑葡萄糖代谢显像是获取最便利、应用最广泛... 详细信息

帕金森病是常见的神经退行性疾病,严重影响患者的生存质量,其早期精准诊断是目前医学一大难题。PET可无创、在体监测帕金森病患者早期脑病理生理改变,具有良好的临床应用价值。^(18)F-FDG PET脑葡萄糖代谢显像是获取最便利、应用最广泛的检测方法。目前已发现多种帕金森病脑内特异性脑代谢模式,对其早期诊断、鉴别诊断、病情监测及疗效判断均有良好效果。本文重点对帕金森病PET葡萄糖代谢模式进行综述,使其更好地应用于帕金森病的诊断。

关键词：帕金森病正电子发射断层摄影术氟脱氧葡萄糖F18 综述

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黑龙江省小城镇城市化与大气污染曲线拟合相关性研究-以集贤县为例

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黑龙江气象 2024年第1期41卷 43-46页

作者：吴松周长明陈莉集贤县气象局黑龙江双鸭山155900 黑龙江省气候中心黑龙江哈尔滨150030

为探究黑龙江省小城镇城市化与大气污染之间的关系,本研究以集贤县2005-2021年的城市面板数据为基础,选取8个城市化指标和3个大气污染指标,采用熵权法构建了城市化和大气污染的综合指标体系,并建立了相关模型进行分析。研究结果显示,在2... 详细信息

为探究黑龙江省小城镇城市化与大气污染之间的关系,本研究以集贤县2005-2021年的城市面板数据为基础,选取8个城市化指标和3个大气污染指标,采用熵权法构建了城市化和大气污染的综合指标体系,并建立了相关模型进行分析。研究结果显示,在2005-2021年期间,集贤县城市化水平呈现稳定且快速的发展趋势。与此同时,大气污染的综合指数却表现出倒“N”型的变化趋势。总体而言,集贤县城市化进程与大气污染之间的关系呈现出特殊的环境库兹涅茨曲线关系,即倒“N”变型曲线模式。

关键词：小城镇城市化大气污染环境库兹涅茨曲线

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High Sensitivity Biomolecular Recognition Device Based on Giant Magnetoresistance Effect

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稀有金属材料与工程 2006年第A3期35卷 522-524页

作者： ming Wang chang-Zhe Wu Tao song Department of Medical Engineering Institute of Electrical Engineering Chinese Academy of Sciences Beijing 100080 China

The structure and microfabrication,the detecting theory and the way of biomolecular recognition device based on giant magnetoresistance(GMR) effect are introduced,also the signal detecting and processing instrumentation are presented. Here the GMR biosensor was fabricated with magnetic tunnel junction(MJT) *** biomolecular recognition device contains an array of MJT sensors,single MJT sensor size is 10μm×20μm,tunneling magnetoresistance ratio(TMR) at room temperature is 52.2%,the typical values of junction resistance-area product Rs is 2.6 kΩμm^2,detecting sensitivity of this system is about 8×10^(-4) A·m^(-1).Bioadaptation layer of this device was fabricated with PDMS the thickness of which is less than 100 nm.

关键词： giant magnetoresistance(GMR) magnetic tunnel junction(MJT) tunneling magnetoresistance ratio(TMR)

chang’e-6 Returns with Samples from Far Side of Moon

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Bulletin of the Chinese Academy of Sciences 2024年第2期38卷 82-87页

作者： song Jianlan 不详

At 2:07 pm GMT+8 on June 25,2024,the returner of chang’e-6,China’s lunar detector,touched down on the ground surface of the preset landing site in Inner Mongolia of *** were samples first-ever collected from the far side of the Moon,the mysterious kingdom that had resisted visits from the human *** soft landing has thus crowned the high-profile mission with a complete success.

关键词： China. return crown

High-performance single-wall carbon nanotube transparent conductive films

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Journal of Materials Science & Technology 2019年第11期35卷 2447-2462页

作者： song Jiang Peng-Xiang Hou chang Liua Hui-ming Cheng Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Physical Science and Technology ShanghaiTech UniversityShanghai200031China State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai200050China University of Chinese Academy of Sciences Beijing100049China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang110016China Tsinghua-Berkeley Shenzhen Institute Tsinghua UniversityShenzhen518055China

A single-wall carbon nanotube(SWCNT)has superior optical,electrical,and mechanical properties due to its unique structure and is therefore expected to be able to form flexible high-performance transparent conductive films(TCFs).However,the optoelectronic performance of these films needs to be improved to meet the requirements of many *** electrical resistivity of SWCNTTCFs is mainly determined by the intrinsic resistivity of individual SWCNTs and their junction resistance in *** analyze these key factors and focus on the optimization of SWCNTs and their networks,which include the diameter,length,crystallinity and electrical type of the SWCNTs,and the bundle size and interconnects in networks,as well as chemical doping and microgrid *** conclude that isolated/small-bundle,heavily doped metallic or semiconducting SWCNTs with a large diameter,long length and high crystallinity are necessary to fabricate high-performance SWCNTTCFs.A simple,controllable way to construct macroscopic SWCNT networks with Y-type connections,welded junctions or microgrid design is important in achieving a low ***,some insights into the key challenges in the manufacture and use of SWCNT TCFs and their prospects are presented,hoping to shed light on promoting the practical application of SWCNT TCFs in future flexible and stretchable optoelectronics.

关键词： Single-wall carbon nanotube Transparent conductive film Junction resistance Bundle Doping

A review on the structure-performance relationship of the catalysts during propane dehydrogenation reaction

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Petroleum Science 2022年第2期19卷 819-838页

作者： Bohan Feng Yue-chang Wei Wei-Yu song Chun-ming Xu State Key Laboratory of Heavy Oil Processing College of ScienceChina University of PetroleumBeijing102249People's Republic of China

Dehydrogenation of propane(PDH)technology is one of the most promising on-purpose technologies to solve supply-demand unbalance of *** industrial catalysts for PDH,such as Pt-and Cr-based catalysts,still have their own limitation in expensive price and security ***,a deep understanding into the structure-performance relationship of the catalysts during PDH reaction is necessary to achieve innovation in advanced high-efficient *** this review,we focused on discussion of structure-performance relationship of catalysts in *** on analysis of reaction mechanism and nature of active sites,we detailed interaction mechanism between structure of active sites and catalytic performance in metal catalysts and oxide *** relationship between coke deposition,co-feeding gas,catalytic activity and nanostructure of the catalysts are also *** these discussions on the relationship between structure and performances,we try to provide the insights into microstructure of active sites in PDH and the rational guidance for future design and development of PDH catalysts.

关键词： Dehydrogenation of propane Metal catalysts Oxide catalysts Structure-performance relationship Active site Reaction mechanism

Modeling turbulent heat fluxes over Arctic sea ice using a maximum-entropy-production approach

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Advances in Climate change Research 2021年第4期12卷 517-526页

作者： ZHANG Yi-ming song Mi-Rong DONG chang-ming LIU Ji-Ping School of Marine Science Nanjing University of Information Science and TechnologyNanjing210044China LASG Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing100029China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai519000China Department of Atmospheric and Environmental Sciences University at AlbanyState University of New YorkAlbanyNY12222USA

Recently,an algorithm of surface turbulent heat fluxes over snow/sea ice has been developed based on the theory of maximum entropy production(MEP),which is fundamentally different from the bulk flux algorithm(BF)that has been used in sea ice models for a few *** this study,we first assess how well the MEP algorithm captures the observed variations of turbulent heat fluxes over Arctic sea *** is found that the calculated heat fluxes by the MEP method are in good agreement with in-situ observations after considering the absorption of incoming radiation in a snow/ice surface layer with infinitesimal *** then investigate the effects of two different schemes(MEP ***)in the sea ice model of CICE6 on simulated turbulent heat fluxes and sea ice processes in the Arctic *** results show that the two different schemes give quite different representations of seasonal variations of heat fluxes,particularly for sensible heat fluxes in *** heat fluxes simulated by the MEP produce weak cooling effect on the ice surface in summer,whereas the BF generates a warming *** a result,compared to the BF,the MEP leads to a reduced seasonal cycle of Arctic sea ice mass flux by modulating snow-to-ice conversion,basal ice growth,surface ice melt and basal ice melt.

关键词： Sea ice modeling Turbulent heat fluxes Maximum-entropy-production Mass flux

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“自然辩证法概论”课程混合式教学初探

教学研究 2024年第2期47卷 87-92页

作者：张明国万长松北京化工大学马克思主义学院北京100029 江南大学马克思主义学院江苏无锡214122

数字化和新媒体时代促使“自然辩证法概论”课程采取“线上+线下”混合式教学新模式。线上教学能够做到学习前移、拓展空间,为线下教学奠定基础;线下教学通过专题讲授、翻转课堂等形式达到深度学习进而提高教学质量的目的。创建慕课堂... 详细信息

数字化和新媒体时代促使“自然辩证法概论”课程采取“线上+线下”混合式教学新模式。线上教学能够做到学习前移、拓展空间,为线下教学奠定基础;线下教学通过专题讲授、翻转课堂等形式达到深度学习进而提高教学质量的目的。创建慕课堂和实施过程考核,能够使线上教学和线下教学相互联系、融为一体,进一步提高“自然辩证法”的教学质量。

关键词：自然辩证法概论混合式教学调查分析