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Uranium isotopes of aeolian dust deposited in northern Tibetan Plateau glaciers:Implications for tracing aeolian dust provenance

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Fundamental Research 2022年第5期2卷 716-726页

作者： xiaoyu Jiao Zhiwen dong Janice Brahney Eric J.R.Parteli Fangzhou Li Marcelli Augusto Ting Wei State Key Laboratory of Cryosphere Sciences Northwest Institute of Eco-Environment and ResourcesChinese Academy of Sciences(CAS)Lanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China Department of Watershed Sciences Utah State UniversityLoganUT 84322USA Faculty of Physics University of Duisburg-EssenDuisburg 47057Germany School of Atmospheric Sciences Sun Yat-sen UniversityGuangzhou 510275China CNR-Istituto Struttura della Materia and Elettra-Sincrotrone Trieste Basovizza Area Science ParkTrieste 34149Italy

Asian dust comprises a large portion of the northern hemisphere atmospheric dust load,thereby exerting substantial influence on the Earth’s climate,global biogeochemistry and hydrological cycle through accelerated snow and ice melt.Dust deposited on alpine glaciers encodes information on broad scale atmospheric-environmental processes.The(^(234)U/^(238)U)values of dust fine particulates can reflect the comminuting time and intermediate processes;thus,it provides a new method for the provenance of aeolian dust in the glacial snowpack/cryoconite.Here we present results from a comprehensive survey of uranium isotopic concentrations in dust collected from cryoconites on the glaciers of the northern Tibetan Plateau(TP).These results indicate significant spatial heterogeneity in the(^(234)U/^(238)U)values associated with snowpack/cryoconite dust over a broad range of glaciers in the northern TP.The values of the(^(234)U/^(238)U)ratio in the glaciers of western Qilian Mountains(Qiyi Glacier,Shiyi Glacier,Laohugou Glacier No.12)were the highest,followed by the Tanggula(Dunkemadi Glacier)and Kunlun Mountains(Yuzhufeng Glacier),whereas these values were the lowest in the eastern Qilian Mountains(Jingyangling Snowpack,Dabanshan Snowpack,Lenglongling Glacier).By including the analysis of Sr-Nd isotopic compositions,we find the spatial isotopic distribution reflects a combination of local dust,which is associated with short comminuting times,and dust transported over long ranges.Meteorological data indicate that the dust production in the west and north TP,Alxa arid lands and Gobi Deserts,may have a significant impact on the TP glaciers.Moreover,U-Sr-Nd isotopic composition and end-member mixing models(EMMA)were used in our study to find out the relative contribution of distinct Asian dust sources to the dust budget in the TP glaciers.The results reveal that snowpack/cryoconite dust is derived from both local sources(low comminution signatures)as well as other dust sources in the Asian region.Our study demonstrates the potent

关键词： Uranium isotopes Aeolian dust provenance (^(234)U/^(238)U)values Dust budget Tibetan Plateau glaciers

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基于磁共振深度学习重建算法缩短扫描时间的可行性分析:水模研究

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诊断学理论与实践 2024年第2期23卷 131-138页

作者：吕晓宇冯威铭周慧赟李纪强董海鹏黄娟上海交通大学医学院附属瑞金医院放射科上海200025

目的:旨在评估深度学习重建(deep learning reconstruction, DLR)算法在缩短磁共振成像(magnetic resonance imaging, MRI)扫描时间方面的应用潜力。方法:利用水模,采用控制变量法描绘扫描时间随着激励次数(number of excitation,NEX)... 详细信息

目的:旨在评估深度学习重建(deep learning reconstruction, DLR)算法在缩短磁共振成像(magnetic resonance imaging, MRI)扫描时间方面的应用潜力。方法:利用水模,采用控制变量法描绘扫描时间随着激励次数(number of excitation,NEX)、矩阵、l-to-noise ratio,SNR)及主观图像质量变化(包括锐利度及细节清晰度、失真度的四分制评估),并描绘变化曲线、计算拟合曲线。结果:在传统重建和不同降噪水平的DLR重建中,NEX和分辨率与MRI扫描时间和SNR之间存在正相关性。在相同的NEX和分辨率条件下,传统重建、DLR_L、DLR_M和DLR_H的SNR依次升高。以主观评价3或者4分为令人满意的图像,当矩阵固定为512×512时,不同NEX值下,DLR重建的图像在锐利度、失真度和细节显示方面均表现出色,且在NEX为3、5、7和11时,图像细节显示最佳,同时显著缩短了扫描时间。当NEX为2、4、5、6时,图像的失真令人满意,当NEX为3、5、7和11时,可获得满意的细节显示。以上所有组合,可节省扫描时间31~244 s。随着分辨率的增加,图像质量在锐利度、失真度和细节显示方面均有所提升,失真度较低。当NEX固定为6时,DLR_H、DLR_M、DLR_L及传统重建的图像分别在矩阵为320×320、384×384、448×448及640×640时,即扫描时间分别为141 s、141 s、187 s及232 s时,可获得令人满意的锐利度。DLR_H和DLR_M在512×512矩阵下实现了较小的失真度,而DLR_L和传统重建需要更高的成像矩阵和更长的扫描时间以获得类似的图像质量。对于细节显示的清晰度,DLR_H在512×512矩阵下的表现尤为突出,扫描时间少于DLR_M、DLR_L及传统重建。结论:DLR,特别是DLR_H,可在降低NEX和分辨率以缩短MRI扫描时间的同时,不仅能保持令人满意的SNR和图像细节显示,还有可能实现更高的图像清晰度和更低的失真度。

关键词：深度学习重建激励次数图像质量

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Exploring the structural properties of cathode and anode materials in Li-ion battery via neutron diffraction technique

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Chinese Journal of Structural Chemistry 2023年第5期42卷 44-55页

作者： Yuxi Luo xiaoyu Gao Mingjie dong Tao Zeng Ziwei Chen Maolin Yang Zhongyuan Huang Rui Wang Feng Pan Yinguo Xiao School of Advanced Materials Peking UniversityShenzhen Graduate SchoolShenzhen518055China

As a unique microprobe for structure and dynamics of materials,neutron possesses superior ability in penetration as well as sensitivity for light and magnetic elements in comparison with X-ray and electron.As for the research and development of lithium-ion batteries(LIBs),neutron diffraction techniques play an indispensable role in exploring the structural properties of various electrode materials,especially the detailed structural evolution of cathode and anode materials during electrochemical cycling.Moreover,based on thorough analysis of neutron diffraction results,an in-depth and systematic understanding of some fundamental mechanisms,such as the formation mechanism of defects and migration mechanism of lithium ions,could also be established,which is essential for the development of high-performance electrode materials for the next-generation LIBs.Nevertheless,that technique would not seem to be widely applied yet in comparison with the application of X-ray diffraction and more attention should be paid.To demonstrate the advantages of neutron diffraction technique in research of LIBs materials,this work systematically summarizes representative neutron diffraction studies on exploring structural details hidden in electrode materials and on probing structural evolution of electrode materials during charge/discharge processes.Prospects for further applications of neutron diffraction techniques in research of LIBs are also put forward.

关键词： Neutron diffraction Lithium-ion battery Cathode and anode materials In operando characterization

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云南省锗矿资源成矿规律概要

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地球学报 2024年第4期45卷 481-492页

作者：薛戈王小虎刀艳周家喜邢程肖高强苏肖宇曹晓民董涛李蓉罗建宏云南省地质调查局云南昆明650051 自然资源部三江成矿作用及资源勘查利用重点实验室云南昆明650051 昆明理工大学国土资源工程学院云南昆明650093 云南省三江成矿作用及资源勘查利用重点实验室云南昆明650051 云南大学地球科学学院云南省高校关键矿产成矿学重点实验室云南昆明650500

锗(Ge)矿是我国的战略矿种,也是云南省优势矿产。云南已探明Ge资源储量大,开发利用程度高,找矿空间大,主要包括煤层型和碳酸盐岩容矿型两类矿床。其中,煤层型锗矿床主要分布在滇西腾冲、芒市、沧源、临沧、澜沧等地,形成时代相对集中,... 详细信息

锗(Ge)矿是我国的战略矿种,也是云南省优势矿产。云南已探明Ge资源储量大,开发利用程度高,找矿空间大,主要包括煤层型和碳酸盐岩容矿型两类矿床。其中,煤层型锗矿床主要分布在滇西腾冲、芒市、沧源、临沧、澜沧等地,形成时代相对集中,为新近纪;碳酸盐岩容矿型锗矿床主要分布在滇东北东川、会泽、彝良、鲁甸等地,与铅锌矿床同体共生,形成时代普遍认为是三叠纪。本文全面梳理这两类矿床的成矿地质条件和资源空间分布特征,总结了其成矿规律;综合圈定出找矿预测区共23处。由此提出,当前应加强现有Ge矿床深部和外围地区接替资源找探矿及综合回收利用研究,及时对找矿预测区和有利远景区进行找矿勘查与靶区优选工作,尽快实现老区资源增储和新区找矿突破,为打造世界级Ge资源产业基地和国家Ge矿资源战略储备需求提供资源和技术保障。

关键词：锗矿矿床类型成矿规律云南省

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滇西北浪都夕卡岩矿床致矿岩体的岩石地球化学、年代学、Sr-Nd-Pb同位素组成及其地质意义

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沉积与特提斯地质 2024年第2期44卷 421-436页

作者：莫雷沈啟武陈喜连吴练荣张传昱董桥峰苏肖宇施宝生余海军冷成彪东华理工大学核资源与环境国家重点实验室江西南昌330013 云南迪庆有色金属有限责任公司云南香格里拉674400 云南省地质调查院云南昆明650216 云南省三江成矿作用及资源勘查利用重点实验室云南昆明650051 自然资源部三江成矿作用及资源勘查利用重点实验室云南昆明650051

滇西北浪都侵入岩体位于义敦岛弧南段的中甸弧,在空间上属浪都夕卡岩型铜矿床的致矿岩体。本文以浪都致矿岩体中石英二长斑岩为对象,对其开展了锆石SIMS(二次离子质谱)U-Pb定年、岩石地球化学和Sr-Nd-Pb同位素研究。锆石U-Pb定年结果显... 详细信息

滇西北浪都侵入岩体位于义敦岛弧南段的中甸弧,在空间上属浪都夕卡岩型铜矿床的致矿岩体。本文以浪都致矿岩体中石英二长斑岩为对象,对其开展了锆石SIMS(二次离子质谱)U-Pb定年、岩石地球化学和Sr-Nd-Pb同位素研究。锆石U-Pb定年结果显示浪都石英二长斑岩的成岩年龄为219.2±1.8 Ma(2σ,MSWD=1.3,n=13),与中甸弧中晚三叠世侵入岩体成岩年龄基本一致。浪都石英二长斑岩具有中等SiO2含量(w(SiO_(2))为60.42%~66.44%),高Al_(2)O_(3)(w(Al2O3)为14.56%~16%)和高K2O(w(K_(2)O)为3.49%~4.49%)含量,以富集LREE和Rb、Ba、Sr等大离子亲石元素,相对亏损HREE和Ta、Nb、Ti等高场强元素为特征,在化学成分上属于高钾钙碱性系列。此外,浪都石英二长斑岩的87Sr/86Sr初始值为0.7054~0.7061,εNd(t)值为-3.5~-2.5,且所有样品在Pb同位素构造模式图上均落在造山带演化线附近。结合浪都石英二长斑岩的成岩时代、岩石化学和同位素特征,本文认为浪都致矿岩体形成于晚三叠世甘孜-理塘洋壳西向俯冲增生的构造背景,是交代地幔部分熔融形成的熔体在上升过程中受到下地壳物质混染,并经历分离结晶作用形成的产物。浪都石英二长斑岩的高Sr/Y比值和高V/Sc比值,指示岩浆具有高含量H2O和较高的氧逸度,是该区斑岩-夕卡岩铜矿床形成的关键。

关键词：浪都致矿岩体岩石地球化学锆石U-Pb年龄 Sr-Nd-Pb同位素

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辣椒幼苗体内理化指标与疫病抗性的关系

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长江蔬菜 2024年第8期 17-21页

作者：常晓轲董晓宇韩娅楠程志芳姚秋菊李丽河南省农业科学院蔬菜研究所河南郑州450000

为探明辣椒幼苗根系和叶片中理化指标与疫病抗性的关系,利用灌根法对抗、感疫病的品系接种辣椒疫病病菌,测定接种后幼苗根系和叶片中超氧化物歧化酶(SOD)、过氧化物歧化酶(POD)、过氧化物酶(CAT)、丙二醛(MDA)、可溶性蛋白含量的变化。... 详细信息

为探明辣椒幼苗根系和叶片中理化指标与疫病抗性的关系,利用灌根法对抗、感疫病的品系接种辣椒疫病病菌,测定接种后幼苗根系和叶片中超氧化物歧化酶(SOD)、过氧化物歧化酶(POD)、过氧化物酶(CAT)、丙二醛(MDA)、可溶性蛋白含量的变化。结果表明,接种后抗、感品系根系和叶片中SOD、POD、CAT、可溶性蛋白、MDA含量均有明显变化,说明它们在辣椒抵御病原菌侵染中发挥重要作用;抗病品系叶片的SOD、POD、CAT活性和根系的SOD活性、可溶性蛋白含量高于感病品系,感病品系叶片和根系的MDA含量高于抗病品系。接种后根系的SOD、POD、CAT活性变化幅度大于叶片。

关键词：辣椒疫病病菌理化指标抗性

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The Genetics of Clinical Liver Diseases: Insight into the TM6SF2 E167K Variant

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Journal of Clinical and Translational Hepatology 2018年第3期6卷 326-331页

作者： xiaoyu Zhang Shousheng Liu Quanjiang dong Yongning Xin Shiying Xuan Department of Gastroenterology Taishan Medical UniversityTaianChina Department of Infectious Disease Qingdao Municipal HospitalQingdaoChina Department of Gastroenterology Qingdao Municipal HospitalQingdaoChina Digestive Disease Key Laboratory of Qingdao QingdaoChina Central Laboratories Qingdao Municipal HospitalQingdaoChina

The transmembrane 6 superfamily member 2(TM6SF2)gene E167K variant(rs58542926)was identified by exome-wide as-sociation study as a nonsynonymous single nucleotide poly-morphism associated with nonalcoholic fatty liver disease.The TM6SF2 E167K variant features a C-to-T substitution at nucleotide 499,encoding a glutamate with lysine change at codon 167(E167K).TM6SF2 is markedly expressed in the liver,small intestine and kidney,and has been proposed as an im-portant risk factor for diseases associated with lipid metabo-lism.Subsequently,multifunctional studies of the TM6SF2 E167K variant have been carried out in a spectrum of liver dis-eases,such as nonalcoholic fatty liver disease,nonalcoholic steatohepatitis,fibrosis,cirrhosis,and viral hepatitis.This re-view summarizes the research status of the TM6SF2 E167K variant in different liver diseases and specific populations,and discusses the potential mechanisms of the TM6SF2 E167K var-iant's role in the progression of various liver diseases.

关键词： TM6SF2 SNP NAFLD Fibrosis Cirrhosis Virus hepatitis

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天山胜利隧道施工关键技术创新与应用

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现代隧道技术 2024年第2期61卷 241-253,271页

作者：李宗平王帅帅毛锦波李亚隆牛晓宇中国交通建设集团有限公司北京100088 中交集团山区长大桥隧建设技术研发中心西安710100 中交二公局东萌工程有限责任公司西安710119 中交第二公路工程局有限公司西安710065

新疆乌尉高速天山胜利隧道全长22.13 km,是目前世界在建最长的高速公路隧道,工程建设面临高寒、高海拔等复杂恶劣环境影响下建设20 km级超长大埋深高速公路山岭隧道的多项挑战。作为国内公路行业首次采用TBM辅助施工的三洞隧道模式,文... 详细信息

新疆乌尉高速天山胜利隧道全长22.13 km,是目前世界在建最长的高速公路隧道,工程建设面临高寒、高海拔等复杂恶劣环境影响下建设20 km级超长大埋深高速公路山岭隧道的多项挑战。作为国内公路行业首次采用TBM辅助施工的三洞隧道模式,文章系统介绍天山胜利隧道在施工组织、物料运输、施工通风、TBM施工、竖井作业等方面的关键创新技术,创新性地提出适用于超特长隧道的“长隧超短打”三洞法施工组织、TBM无轨物料运输、TBM压注式混凝土工艺、洞顶正上方悬挂式连续皮带机、多工作面施工通风、深大竖井地面深部预注浆技术、短掘短衬作业法等新技术、新工艺、新设备,为今后超特长隧道施工提供系统参考,对提升超特长隧道建造水平具有重要意义。

关键词：天山胜利隧道施工组织物料运输 TBM仰拱块悬挂式皮带机多功能胶轮车

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Ultraviolet photodetectors based on ferroelectric depolarization field

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Journal of Energy Chemistry 2023年第2期77卷 487-498,I0013页

作者： xiaoyu Zhou Qingqing Ke Silin Tang Jilong Luo Zihan Lu School of Microelectronics Science and Technology Sun Yat-sen UniversityZhuhai 519082GuangdongChina Guangdong Provincial Key Laboratory of Optoelectronic Information Processing Chips and Systems Sun Yat-sen UniversityZhuhai 519082GuangdongChina

Ultraviolet(UV)photodetectors are extensively adopted in the fields of the Internet of Things,optical communications and imaging.Nowadays,with broadening the application scope of UV photodetectors,developing integrated devices with more functionalities rather than basic photo-detecting ability are highly required and have been triggered ever-growing interest in scientific and industrial communities.Ferroelectric thin films have become a potential candidate in the field of UV detection due to their wide bandgap and unique photovoltaic characteristics.Additionally,ferroelectric thin films perform excellent dielectric,piezoelectric,pyroelectric,acousto-optic effects,etc.,which can satisfy the demand for the diversified development of UV detectors.In this review,according to the different roles of ferroelectric thin films in the device,the UV photodetectors based on ferroelectric films are classified into ferroelectric depolarization field driven type,ferroelectric depolarization field and built-in electric field co-driven type,and ferroelectric field enhanced type.These three types of ferroelectric UV photodetectors have great potential and are expected to promote the development of a new generation of UV detection technology.At the end of the paper,the advantages and challenges of three types of ferroelectric UV photodetectors are summarized,and the possible development direction in the future is proposed.

关键词： UV photodetector Ferroelectric Thin film Depolarization field Built-in electric field

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Vanadium-based metal-organic frameworks and their derivatives for electrochemical energy conversion and storage

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SmartMat 2022年第3期3卷 384-416页

作者： Jing Zhu xiaoyu Chen Ai Qin Thang Fei‐Long Li dong Chen Hongbo Geng Xianhong Rui Qingyu Yan Department of Applied Chemistry State Key Laboratory of Tea Plant Biology and UtilizationAnhui Agricultural UniversityAnhuiChina School of Materials Science and Engineering Nanyang Technological UniversitySingaporeSingapore School of Materials Engineering Changshu Institute of TechnologyChangshuJiangsuChina School of Materials and Energy Guangdong University of TechnologyGuangzhouChina

With the excessive consumption of nonrenewable resources,the exploration of effective and durable materials is highly sought after in the field of sustainable energy conversion and storage system.In this aspect,metalorganic frameworks(MOFs)are a new class of crystalline porous organicinorganic hybrid materials.MOFs have recently been gaining traction in energy-related fields.Owing to the coordination flexibility and multiple accessible oxidation states of vanadium ions or clusters,vanadium-MOFs(V-MOFs)possess unique structural characteristics and satisfactory electrochemical properties.Furthermore,V-MOFs-derived materials also exhibit superior electrical conductivity and stability when used as electrocatalysts and electrode materials.This review summarizes the research progress of V-MOFs(inclusive of pristine V-MOFs,V/M-MOFs,and POVbased MOFs)and their derivatives(vanadium oxides,carbon-coated vanadium oxide,vanadium phosphate,vanadate,and other vanadium doped nanomaterials)in electrochemical energy conversion(water splitting,oxygen reduction reaction)and energy storage(supercapacitor,rechargeable battery).Future possibilities and challenges for V-MOFs and their derivatives in terms of design and synthesis are discussed.Lastly,their applications in energy-related fields are also highlighted.

关键词： derivatives electrocatalysis rechargeable battery supercapacitor V-based metal-organic frameworks

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