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透射电子显微镜技术在稀土矿床研究中的应用进展

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岩矿测试 2024年第4期43卷 641-658页

作者：徐亦桐宋文磊代静静薛姗娜陈倩杨金昆许丹妮西北大学地质学系大陆动力学国家重点实验室陕西西安710069

透射电子显微镜(简称“透射电镜”)技术具非常高的空间分辨率和多样化的测试功能,可以获取样品非常全面的亚微米-纳米尺度的晶体结构和化学成分信息,是研究地质样品微观组成和结构的强有力工具,近年来越来越多地应用到包括矿床学在内的... 详细信息

透射电子显微镜(简称“透射电镜”)技术具非常高的空间分辨率和多样化的测试功能,可以获取样品非常全面的亚微米-纳米尺度的晶体结构和化学成分信息,是研究地质样品微观组成和结构的强有力工具,近年来越来越多地应用到包括矿床学在内的地球科学研究领域。本文以透射电镜在关键金属稀土矿产资源研究中的应用为例,在简述透射电镜的基本结构、工作原理、功能和制样方法基础上,重点综述了其在揭示碳酸岩型、伟晶岩型、风化壳离子吸附型、磷块岩型和深海沉积物型稀土矿床成矿特征和成因模式研究中的应用进展,包括氟碳铈矿的颗粒附着结晶生长机制,磷灰石和锆石受热液交代导致的矿物溶解、迁移和再沉淀过程,离子吸附型矿床中原生稀土矿物的微观结构和风化产物特征,磷灰石中稀土元素的纳米-原子尺度的赋存状态和替代机制等。提出了透射电镜研究过程中需要注意的事项和应用前景。

关键词：透射电镜稀土矿床稀土矿物纳米矿物

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A High Spatiotemporal Iontronic Single-Cell Viscometer

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Research 2022年第4期2022卷 239-247页

作者： Tianyang Zhang Siyuan Yu Bing Wang yitong xu Xiaomei Shi Weiwei Zhao Dechen Jiang Hongyuan Chen Jingjuan xu State Key Laboratory of Analytical Chemistry for Life Science School of Chemistry and Chemical EngineeringNanjing UniversityNanjing210023China

Ideal single-cell viscometer has remained unachieved,leaving a gap in current palette of single-cell *** of single-cell viscosity could contribute to our knowledge of fundamental biological processes,e.g.,mass diffusion,biochemical interaction,and cellular responses to many diseases and *** advances have been made to this end,existing methods generally suffer from limitations,e.g.,low spatiotemporal ***,we describe a high spatiotemporal iontronic single-cell viscometer that operates upon a patch clamp integrated with double-barreled nanopores separated by a septum of ca.32 *** system enables reversible electroosmotic manipulation of the adjacent small fluid bridging two nanopores,the viscous alternation of which could be sensitively monitored by the ionic *** practical cellular studies,significantly,our findings reveal not only the less deviated medium viscosities than those of lysosomes and mitochondria but also the highest viscosities in the near-nuclear region than those of mitochondrion-dense and lysosome-dense *** work has provided an accessible single-cell viscometer and enriched the armory of single-cell nanotools.

关键词： pores viscosity bridging

Gender and Race Differences in Mental Health and Well-Being Among Older Americans During the COVID-19 Pandemic

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International Journal of Disaster Risk Science 2024年第2期15卷 239-250页

作者： Dongjuan xu Nasreen Lalani yitong Wang School of Nursing Purdue UniversityWest LafayetteIN 47907USA Center on Aging and the Life Course Purdue UniversityWest LafayetteIN 47907USA

The objectives of this study were to investigate(1) gender and race differences in mental health and psychological wellbeing among older adults during the COVID-19 pandemic and(2) whether there were significant interaction effects between gender and race. This study used the National Health and Aging Trends Study(NHATS) and COVID-19 public use data files. It focused on mental health and psychological well-being, including loneliness, no time to yourself, poor sleep quality, anxiety, depression, and post-traumatic stress disorder(PTSD). The sample consisted of 2465 older adults, and multivariate logistic and linear regression models were adopted for the analysis. The results show that approximately two out of five older people(43%) experienced poor sleep, followed by loneliness(35%), anxiety(30%), depression(23%), and no time to themselves(11%). The average PTSD score was 11. Mental health and psychological well-being varied by gender and race. There were significant interaction effects on anxiety and depression between females and Black older adults. Black females reported lower levels of anxiety and depressive symptoms than Black males, although the differences were not statistically significant. Black older adults were more likely to experience PTSD but less likely to feel lonely and have poorer sleep than their White counterparts. Female older adults reported poorer mental health and psychological well-being than males, except for Black females. Black females had the lowest levels of anxiety, depression, loneliness, and highest quality of sleep among all females of different ethnic and racial origins.

关键词： COVID-19 Gender Mental health Older adults Psychological well-being Race and ethnicity United States

Modular Soft Robotic Crawlers Based on Fluidic Prestressed Composite Actuators

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Journal of Bionic Engineering 2024年第2期21卷 694-706页

作者： Zefeng xu Linkai Hu Longya Xiao Hongjie Jiang yitong Zhou Shien-Ming Wu School of Intelligent Engineering South China University of TechnologyGuangzhou511442China School of Mechanical and Electrical Engineering Guangzhou UniversityGuangzhou510006China

Soft robotic crawlers have limited payload capacity and crawling *** study proposes a high-performance inchworm-like modular robotic crawler based on fluidic prestressed composite(FPC)*** FPC actuator is precurved and a pneumatic source is used to flatten it,requiring no energy cost to maintain the equilibrium curved *** and depressurizing the actuators generate alternating stretching and bending motions of the actuators,achieving the crawling motion of the robotic ***-modal locomotion(crawling,turning,and pipe climbing)is achieved by modular reconfiguration and gait *** analytical kinematic model is proposed to characterize the quasi-static curvature and step size of a single-module *** configurations of robotic crawlers are fabricated to demonstrate the crawling ability of the proposed design.A set of systematic experiments are set up and conducted to understand how crawler responses vary as a function of FPC prestrains,input pressures,and actuation *** per the experiments,the maximum carrying load ratio(carrying load divided by robot weight)is found to be 22.32,and the highest crawling velocity is 3.02 body length(BL)per second(392 mm/s).Multi-modal capabilities are demonstrated by reconfiguring three soft crawlers,including a matrix crawler robot crawling in amphibious environments,and an inching crawler turning at an angular velocity of 2/s,as well as earthworm-like crawling robots climbing a 20 inclination slope and pipe.

关键词： Soft robot Soft crawler Fluidic prestressed composite Kinematic model Enhanced loading Multi-modal capability

锌指蛋白ZNF23在非小细胞肺癌中表达的研究

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中国实验诊断学 2024年第1期28卷 57-63页

作者：曲微任洪久徐艺桐邱雪杉赵俊军大连理工大学附属中心医院病理科辽宁大连116000 中国医科大学附属第一医院病理科辽宁沈阳110000

目的探讨ZNF23非小细胞肺癌中的表达、对肺癌生物学行为的影响及相关作用机制。方法免疫组化检测非小细胞肺癌组织中ZNF23表达,Western Blot及realtime PCR方法检测ZNF23在癌与癌旁组织中蛋白及mRNA表达,siRNA转染及细胞周期实验检测Z... 详细信息

目的探讨ZNF23非小细胞肺癌中的表达、对肺癌生物学行为的影响及相关作用机制。方法免疫组化检测非小细胞肺癌组织中ZNF23表达,Western Blot及realtime PCR方法检测ZNF23在癌与癌旁组织中蛋白及mRNA表达,siRNA转染及细胞周期实验检测ZNF23在调节细胞周期进展中发挥的作用。结果与癌旁正常组织相比,ZNF23在非小细胞肺癌临床石蜡切片中表达降低,并与组织类型、分化程度、TNM分期、淋巴结转移相关;Western Blot及realtime PCR结果显示ZNF23的蛋白及mRNA水平在癌旁正常组织中多于癌组织。流式细胞仪结果显示ZNF23干扰细胞周期进展较快,多在S/G2期。结论 ZNF23在非小细胞肺癌组织中的表达低于癌旁正常组织,是一个癌症抑制因子,并且可以通过阻滞细胞周期进展而抑制细胞增殖,从而发挥肿瘤抑制作用。

关键词： ZNF23 锌指蛋白细胞周期非小细胞肺癌

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N235从废催化剂沉钒废液中回收钒

矿产综合利用 2024年第4期45卷 118-122页

作者：朱军郭梅刘心海徐翌童李小鹏刘丹阳西安建筑科技大学冶金工程学院陕西西安710055 陕西宝德赛肯光电材料有限公司陕西西安710055

这是一篇冶金工程领域的论文。针对陕西某炼锌厂废催化剂的沉钒废液,通过溶剂萃取法除杂并回收沉钒废液中的钒,考查N235体积分数、萃取相比、萃取时间、萃取级数等对钒萃取率的影响。结果表明:采用30%N235+5%TBP+65%的磺化煤油的萃取体... 详细信息

这是一篇冶金工程领域的论文。针对陕西某炼锌厂废催化剂的沉钒废液,通过溶剂萃取法除杂并回收沉钒废液中的钒,考查N235体积分数、萃取相比、萃取时间、萃取级数等对钒萃取率的影响。结果表明:采用30%N235+5%TBP+65%的磺化煤油的萃取体系经过四级逆流萃取,萃取相比V_(O)/V_(A)=2∶1,萃取时间t=5 min,钒的萃取率为95.68%;反萃取剂Na_(2)CO_(3)体积分数为5%,反萃相比V'_(O)/V'_(A)=4∶1,反萃时间t=4 min,经三级逆流反萃取,钒的反萃取率为98.25%。

关键词：冶金工程沉钒废液钒萃取 N235 磺化煤油

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Frontiers of Computer Science 2020年第3期14卷 113-128页

作者： Yun PENG yitong xu Huawei ZHAO Zhizheng ZHOU Huimin HAN Research Center of Big Data Application Qilu University of TechnologyJinan 250353China Data Science Institute Columbia UniversityNew York 10027USA College of Mechanics and Materials Hohai UniversityNanjing 210098China

This paper studies the most similar maximal clique query(MSMCQ).Given a graph G and a set of nodes Q,MSMCQ is to find the maximal clique of G having the largest similarity with *** has many real applications including advertising industry,public security,task crowdsourcing and social network,*** can be studied as a special case of the general set similarity query(SSQ).However,the MCs of G has several specialties from the general *** on the specialties of MCs,we propose a novel index,namely *** outperforms the state-of-the-art SSQ method significantly in terms of the number of candidates and the query ***,we first construct an inverted indexⅠfor all the MCs of *** the MCs in a posting list often have a lot of overlaps,MCIndex selects some pivots to cluster the MCs with a small *** a query Q,we compute the distance from the pivots to *** clusters of the pivots assured not answer can be pruned by our distance based pruning *** it is NP-hard to construct a minimum MCIndex,we propose to construct a minimal MCIndex onⅠ(v)with an approximation ratio 1+ln|Ⅰ(v)|.Since the MCs have properties that are inherent of graph structure,we further propose a S Index within each cluster of a MCIndex and a structure based pruning rule.S Index can significantly reduce the number of *** the sizes of intersections between Q and many MCs need to be computed during the query evaluation,we also propose a binary representation of MCs to improve the efficiency of the intersection size *** extensive experiments confirm the effectiveness and efficiency of our proposed techniques on several real-world datasets.

关键词： most similar maximal clique similarity query graph data

Quantifying the impact of earthquakes and geological factors on spatial heterogeneity of debris-flow prone areas:A case study in the Hengduan Mountains

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Journal of Mountain Science 2024年第5期21卷 1522-1533页

作者： HU xudong SHEN yitong HU Kaiheng xu Wennian LIU Daxiang HE Songtang GAO Jiazhen WEI Li LIU Shuang Hubei Provincial Engineering Research Center of Slope Habitat Construction Technique Using Cement-based Materials(China Three Gorges University) Yichang 443002China Hubei Key Laboratory of Disaster Prevention and Mitigation(China Three Gorges University) Yichang 443002China College of Civil Engineering and Architecture China Three Gorges UniversityYichang 443002China Shanghai Investigation Design&Research Institute Co.Ltd.Shanghai 200335China Key Laboratory of Mountain Hazards and Earth Surface Processes Chinese Academy of SciencesChengdu 610041China Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China Wuhan Polytechnic Wuhan 430074China

Understanding the spatial heterogeneity of debris-flow-prone areas holds significant implications for regional risk management, particularly in seismically active regions with geological faults. Despite the significance of this knowledge, a comprehensive quantification of the influence of regional topographical and geological factors on the spatial heterogeneity of debris-flow-prone areas has been lacking. This study selected the Hengduan Mountains, an earthquake-prone region characterized by diverse surface conditions and complex landforms, as a representative study area. An improved units zoning and objective factors identification methodology was employed in earthquake and fault analysis to assess the impact of seismic activity and geological factors on spatial heterogeneity of debrisflow prone areas. Results showed that the application of GIS technology with hydrodynamic intensity and geographical units analysis can effectively analyze debris-flow prone areas. Meanwhile, earthquake and fault zones obviously increase the density of debrisflow prone catchments and make them unevenly distributed. The number of debris-flow prone areas shows a nonlinear variation with the gradual increase of geomorphic factor value. Specifically, the area with 1000 m-2500 m elevation difference, 25°-30° average slope, and 0.13-0.15 land use index is the most favorable conditions for debris-flow occurrence;The average annual rainfall from 600 to 1150 mm and landslides gradient from 16° to 35° are the main causal factors to trigger debris flow. Our study sheds light on the quantification of spatial heterogeneity in debris flow-prone areas in earthquake-prone regions, which can offer crucial support for post-debris flow risk management strategies.

关键词： debris-flow prone areas causal factors GIS-based method spatial heterogeneity Hengduan Mountains

Liquid metal in prohibiting polysulfides shuttling in metal sulfides anode for sodium-ion batteries

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Journal of Energy Chemistry 2024年第9期96卷 559-567页

作者： Xiaobo Zheng Xinwei Guan xuan Cheng Xiaoning Li Yang Fu yitong Li Zhi Zheng Weikong Pang xun xu Peng Li Tianyi Ma Institute for Superconducting&Electronic Materials Australian Institute for Innovative MaterialsUniversity of WollongongWollongongNSW 2522Australia School of Science RMIT UniversityMelbourneVIC 3000Australia CSIRO Manufacturing ClaytonVIC 3168Australia

Metal sulfides are a class of promising anode materials for sodium-ion batteries(SIBs)owing to their high theoretical specific ***,the reactant products(polysulfides)could dissolve into electrolyte,shuttle across separator,and react with sodium anode,leading to severe capacity loss and safety ***,for the first time,gallium(Ga)-based liquid metal(LM)alloy is incorporated with MoS_(2)nanosheets to work as an anode in *** electron-rich,ultrahigh electrical conductivity,and self-healing properties of LM endow the heterostructured MoS_(2)-LM with highly improved conductivity and electrode ***,LM is demonstrated to have excellent capability for the adsorption of polysulfides(e.g.,Na_(2)S,Na_(2)S_(6),and S_(8))and subsequent catalytic conversion of Na_(2)***,the MoS_(2)-LM electrode exhibits superior ion diffusion kinetics and long cycling performance in SIBs and even in lithium/potassium-ion battery(LIB/PIB)systems,far better than those electrodes with conventional binders(polyvinylidene difluoride(PVDF)and sodium carboxymethyl cellulose(CMC)).This work provides a unique material design concept based on Ga-based liquid metal alloy for metal sulfide anodes in rechargeable battery systems and beyond.

关键词： GalnSn liquid metal alloy MoS_(2) Polysulfides shuttle effects Catalytic conversion Sodium-ion batteries