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流通式-时间分辨分析技术在地质领域的应用进展

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岩矿测试 2025年第1期44卷 1-18页

作者：许心宁王朔徐娟刘鹏飞杨守业同济大学海洋地质国家重点实验室上海200092

流通式-时间分辨分析系统(简称FT-TRA)是二十一世纪初新发展起来的一种快速反应(溶解)-在线分析系统,由淋洗液混合单元、反应单元与分析单元组成,核心功能是通过特定流动相淋洗样品池中的微量样品,分离或去除样品中的特定组分,并监测样... 详细信息

流通式-时间分辨分析系统(简称FT-TRA)是二十一世纪初新发展起来的一种快速反应(溶解)-在线分析系统,由淋洗液混合单元、反应单元与分析单元组成,核心功能是通过特定流动相淋洗样品池中的微量样品,分离或去除样品中的特定组分,并监测样品不同元素和矿物组分的出溶特征,实现高分辨的在线过程分析。本文综述了FT-TRA系统的技术原理与软硬件组成、实验方法与操作要点及地质应用发展过程,重点对该系统在地质应用过程中出现的争议点进行阐释与分析,并基于其发展现状展望其未来发展方向与潜力。FT-TRA系统目前主要的地质应用包括古海洋学与古环境学研究代用指标的验证(如有孔虫、介形虫淋洗)、矿物溶解过程与反应动力学研究、环境样品的元素相态分析等。FT-TRA系统以溶解并提取有孔虫/介形虫壳体的元素组成信号作为还原古海洋指标的重要手段,与传统批处理法相比,该方法被认为具有实时监测清洁程度、降低损失率并实现差异溶解的优势,能够获取更精细的壳体化学组成信息;测试矿物溶解态与溶解参数也是FT-TRA系统的重要功能之一,该系统的实验室模拟能够与模型结合探究不同类型矿物在稳态下的溶解动力学,为研究矿物在自然状态下的溶解过程提供启示;近些年来该系统还逐渐被用于矿物反应性测试,其中将气相CO_(2)作为淋滤液与矿物反应的研究可能在全球变暖及CO_(2)的人工捕捉课题上具有潜在应用价值。FT-TRA系统运行中涉及的不同组分的溶解机制是其应用过程中亟待解决的重要问题,进一步完善其溶解动力学原理必然将为该系统的未来发展提供更多如多类型地质样品溶解、矿物的模拟合成等新思路。

关键词：流通式-时间分辨分析系统(FT-TRA) 在线地球化学分析地质应用环境研究

Inhibiting the phase transition of WO_(3)for highly stable aqueous electrochromic battery

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journal of Energy Chemistry 2024年第8期95卷 86-95,I0003页

作者： Zhisheng Wu Zhendong Lian Ting Ding jielei Li jincheng xu jinxiao Wang Liangxing Zhang Bo Wang Shi Chen Peng Xiao Hua xu Shuang-Peng Wang Kar Wei ng joint Key Laboratory of the Ministry of Education Institute of Applied Physics and Materials EngineeringUniversity of MacaoAvenida da UniversidadeMacao 999078China School of Applied Physics and Materials Wuyi UniversityJiangmen 529020GuangdongChina Guangdong-Hong Kong-Macao joint Laboratory for Intelligent Micro-Nano Optoelectronic Technology School of Physics and Optoelectronic EngineeringFoshan UniversityFoshan 528225GuangdongChina Guangzhou New Vision Optoelectronic Technology Co. Ltd.Guangzhou 510530GuangdongChina

Aqueous electrochromic battery(ECB)has shown intense potential for achieving energy storage and saving *** tungsten oxide(WO_(3))is the most promising EC material for commercialization,the cycling stability of WO_(3)-based aqueous ECBs is currently unsatisfactory due to the repeated phase transition during the redox process and the corrosion by acidic ***,we present a titanium-tungsten oxide alloy(Ti-WO_(3))with controllable morphology and crystal phase synthesized by a facile hot injection method to overcome the *** contrast to conventional monoclinic WO_(3),the Ti-WO_(3)nanorods can stably maintain their cubic crystal phase during the redox reaction in an acidic electrolyte,thus leading to dramatically enhanced response speed and cycling stability,Specifically,when working in a well-matched hybrid Al^(3+)/Zn^(2+)aqueous electrolyte,our phasetransition-free cubic Ti-WO_(3)exhibits an ultra-high cycling stability(>20000 cycles),fast response speed(3,95 s/4,65 s for bleaching/coloring),as well as excellent discharge areal capacity of 214.5 mA h m^(-2),We further fabricate a fully complementa ry aqueous electrochromic device,for the first time,using a Ti-WO_(3)/Prussian blue device ***,the complementary ECB shows>10000 stable operation cycles,attesting to the feasibility of our Ti-WO_(3)for practical *** work validates the significance of inhibiting the phase transitions of WO_(3)during the electrochromic process for realizing highly cyclable aqueous ECB,which can possibly provide a generalized design guidance for other high-quality metallic oxides for electrochemical applications.

关键词： Aqueous electrochromic battery Ti-WO_(3) Phase transition Long-term stability

基于XLNet和多粒度对比学习的新闻主题文本分类方法

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郑州大学学报（理学版） 2025年第2期57卷 16-23页

作者：陈敏王雷春徐瑞史含笑徐渺湖北大学计算机学院湖北武汉430062

新闻主题文本内容简短却含义丰富,传统方法通常只考虑词粒度或句粒度向量中的一种进行研究,未能充分利用新闻主题文本不同粒度向量之间的关联信息。为深入挖掘文本的词向量和句向量间的依赖关系,提出一种基于XLNet和多粒度特征对比学习... 详细信息

新闻主题文本内容简短却含义丰富,传统方法通常只考虑词粒度或句粒度向量中的一种进行研究,未能充分利用新闻主题文本不同粒度向量之间的关联信息。为深入挖掘文本的词向量和句向量间的依赖关系,提出一种基于XLNet和多粒度特征对比学习的新闻主题分类方法。首先,利用XLNet对新闻主题文本进行特征提取获得文本中词、句粒度的特征表示和潜在空间关系;然后,通过对比学习R-Drop策略生成不同粒度特征的正负样本对,以一定权重对文本的词向量-词向量、词向量-句向量和句向量-句向量进行特征相似度学习,使模型深入挖掘出字符属性和语句属性之间的关联信息,提升模型的表达能力。在THUCNews、Toutiao和SHNews数据集上进行实验,实验结果表明,与基准模型相比,所提方法在准确率和F 1值上都有更好的表现,在三个数据集上的F 1值分别达到了93.88%、90.08%、87.35%,验证了方法的有效性和合理性。

关键词：自然语言处理文本分类新闻主题 XLNet 对比学习

HOT DEFORMATION AND MARTENSITIC TRANSFORMATION BEHAVIORS OF Fe-32%Ni ALLOY

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Acta Metallurgica Sinica(English Letters) 2006年第2期19卷 133-138页

作者： j. Huang Z. xu Cold Rolling Mill Baoshan Iron ＆ Steel Co. Ltd Shanghai 201900 China Key Laboratory for High Temperature Materials and Tests of Ministry of Education Shanghai Jiaotong University Shanghai 200030 China

The Hot deformation and martensitic transformation behaviors of Fe-32%Ni alloy was investigated by measurements of electrical resistance and X-ray diffraction. With the increase in strain, the austenite goes through from the work-hardened to the partial dynamcally re-crystallized and then to the completed dynamically re-crystallized. The martensitic transformation characteristics depend on the austenite states. The work-hardening in small strain is helpful to martensitic transformation due to the low dislocation density and little lattice distortion, while the high dislocation density and severe lattice distortion by the increase in strain will hinder the martensitic nucleation. Once dynamic re-crystallization （ DRX ） takes place, the martensitic transformation will be enhanced again, which is related to the heterogeneous dynamic substructures. The growing DRX grain can enhance the martensitic nucleation due to the low dislocation density near its grain boundary.

关键词： Fe-32%Ni alloy hot deformation work hardening dynamic re-crystallization martensitic transformation

Extragalactic dispersion measures of fast radio bursts

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Research in Astronomy and Astrophysics 2015年第10期15卷 1629-1638页

作者： jun xu j.L.Han National Astronomical Observatories Chinese Academy of Sciences

Fast radio bursts show large dispersion measures, much larger than the Galactic dispersion measure foreground. Therefore, they evidently have an extragalac- tic origin. We investigate possible contributions to the dispersion measure from host galaxies. We simulate the spatial distribution of fast radio bursts and calculate the dis- persion measures along the sightlines from fast radio bursts to the edge of host galaxies by using the scaled NE2001 model for thermal electron density distributions. We find that contributions to the dispersion measure of fast radio bursts from the host galaxy follow a skew Gaussian distribution. The peak and the width at half maximum of the dispersion measure distribution increase with the inclination angle of a spiral galaxy, to large values when the inclination angle is over 70~. The largest dispersion measure produced by an edge-on spiral galaxy can reach a few thousand pc cm-3, while the dispersion measures from dwarf galaxies and elliptical galaxies have a maximum of only a few tens of pc cm-3. Notice, however, that additional dispersion measures of tens to hundreds of pc cm-3 can be produced by high density clumps in host galaxies. Simulations that include dispersion measure contributions from the Large Magellanic Cloud and the Andromeda Galaxy are shown as examples to demonstrate how to ex- tract the dispersion measure from the intergalactic medium.

关键词： galaxies: ISM -- radio continuum: ISM -- ISM: general

Numerical simulation of precipitation kinetics in multicomponent alloys

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journal of Materials Science & Technology 2022年第33期128卷 98-106页

作者： K.xu j.D.Liu S.van der Zwaag W.xu j.G.Li School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China Institute of Metal Research Chinese Academy of SciencesShenyang 110016China Novel Aerospace Materials Group Faculty of Aerospace EngineeringDelft University of TechnologyKluyverweg 12629 HSDelftThe Netherlands State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China

A universal numerical model based on the particle size distribution(PSD)approach has been developed for the simulation of precipitation kinetics in multicomponent alloys during isothermal *** was implemented utilizing the classical nucleation theory(CNT).Growth and coarsening were modeled by a single growth kinetics equation,which is constructed based on the interfacial diffusion flux balance and the capillarity *** partial off-diagonal terms in the diffusion matrix(diffusion of individual components in the matrix)were taken into account in the calculations to minimize the computational cost while coupling with CALPHAD to extract thermodynamics equilibrium around the interface.A new feature of the model is the incorporation of a more realistic spatial site distribution via a Voronoi construction in the characteristic cell,for the purpose of modifying the diffusion *** predictions of the precipitate dimensions and the precipitation kinetics were compared with the atom probe tomography(APT)measurements on ternary Ni-Al-Cr alloys isothermally aged at 873 *** is found that the temporal evolution of the dimensions and composition of the precipitates is well captured,as is the dependence on changes in the alloy *** new modification with Voronoi construction demonstrates that the overall precipitation kinetics depends on the density and the spatial site distribution of *** ability to handle sophisticated alloy chemistries by quantitative equations,the compositional sensitivity of microstructural characteristics emerging from the simulation results,and the ability to visualize the spatial distribution of precipitates make the work very promising for multicomponent alloy design and optimization.

关键词： Precipitation kinetics Thermodynamics Multicomponent PSD Voronoi construction

Moduli of Polarized Calabi–Yau Pairs

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Acta Mathematica Sinica,English Series 2020年第6期36卷 631-637页

作者： jános KOLLáR Chen Yang xu Princeton University Princeton NJ 08544-1000USA MIT CambridgeMA 02139-4307USA

We prove that the irreducible components of the moduli space of polarized Calabi–Yau pairs are projective.

关键词： Polarized Calabi–Yau stable pairs Moduli spaces

Filters and structure of lattice implication algebra

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Chinese Science Bulletin 1997年第18期42卷 1517-1520页

作者： Liu, j xu, Y Department of Applied Mathematics Southwest Jiaotong University Chengdu China

IN order to research the logical system whose propositional value is given in a lattice from

关键词： lattice implication algebra filter generated filter.

主动式气膜冷却对高超声速飞行器等离子体鞘套的影响

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中山大学学报（自然科学版）（中英文） 2025年第1期64卷 250-256页

作者：徐春光张源耕中山大学航空航天学院广东深圳518107

以钝锥模型为研究对象,采用热化学非平衡计算方法并结合可压缩N-S方程、SST k-ω湍流模型,对钝锥模型肩部台阶喷流和头部逆向喷流流场进行了数值模拟。在考虑不同喷流压强、喷口位置和数量等因素的基础上,分析了主动式气膜冷却对等离子... 详细信息

以钝锥模型为研究对象,采用热化学非平衡计算方法并结合可压缩N-S方程、SST k-ω湍流模型,对钝锥模型肩部台阶喷流和头部逆向喷流流场进行了数值模拟。在考虑不同喷流压强、喷口位置和数量等因素的基础上,分析了主动式气膜冷却对等离子体鞘套的影响。结果表明:高超声速飞行器采用主动式气膜冷却技术时,喷口的数量、位置及喷流压强对等离子体密度均具有显著的影响。肩部的切向喷流可有效抑制模型壁面附近的等离子体密度,进而可能对高频电磁波的传输和目标雷达散射截面(RCS)产生影响。头部逆向喷流可显著改变等离子体的分布情况,不同的逆向喷流参数配置会导致明显的差异。

关键词：高超声速飞行器等离子体鞘套主动式气膜冷却热化学非平衡双温模型

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