Results 51 to 60 of about 12,470 (167)
Investigation of Irradiation Behavior and Corrosion Properties of the N36 Zr Alloy Developed by China [PDF]
本文对中国核动力研究设计院自主研发的两种制备工艺的N36锆合金进行了微观组织与微观化学分析和表征。采用400千伏离子注入机对锆合金进行辐照,分析辐照后的微观结构,以研究其辐照行为与规律。采用高温高压反应釜对原始态锆合金和受辐照的锆合金进行了腐蚀,分析了不同实验条件下锆合金表面氧化层、氧化膜/金属界面和金属基体的微观结构演变规律与特点。 增加冷轧次数与退火过程会导致锆合金的晶粒尺寸变大和不均匀化,平均尺寸从3.9μm长大到6.0μm;且析出相的尺寸变大、弥散程度降低,平均尺寸从74.6nm长大至89 ...
刘臣伟
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ABSTRACT Enhancing the strength of 7000 series high‐strength Al alloys remains a critical challenge to meet the demands of increasingly demanding service environments. In this study, a novel approach is proposed for developing high‐performance Al alloys through a combination of powder mechanical alloying, powder press‐forming, rolling deformation, and ...
Peng‐Fei Ji +4 more
wiley +1 more source
实验研究了厚度d 对ZnO压敏电阻片残压比Kr 的影响规律, 表明残压比同样存在几何效应;实验还表明残压比Kr 随电位梯度E1m A成反比例下降,随平均晶粒尺寸μ的增大而增大; 找到了一个综合微观结构参数 平均晶粒尺寸μ和晶粒尺寸方差σ2 的乘积(σ2μ), 能较好地反映电性能与微观结构参数的关系。提出了计算机模拟微观结构模型,并用计算机模拟了残压比Kr 和厚度d、Kr 和平均晶粒尺寸μ以及Kr 和乘积σ2μ的关系 ...
李盛涛 +5 more
doaj
Verification and Application Case Analysis of the Methods of Increasing the TEM Image Contrast [PDF]
当前,透射电子显微镜(transmissionelectronmicroscope,简称TEM)已成为研究材料微观结构的重要仪器,在利用TEM获取微结构图像时,图像衬度低是较常出现的一个问题。目前鲜有文献针对这一问题开展全面性和系统性的讨论。本文对增加图像衬度的多种理论途径进行了实验验证,并讨论了不同典型低衬度样品的衬度改善方法,使TEM用户可根据实验条件和试样特点,选择有效的解决方案。 1、分别对物镜极靴、物镜光阑、低压电镜和高角度环形探测器等仪器方法以及染色技术 ...
许斌斌
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ABSTRACT Weakening the electrostatic attraction between Mg2+ ions and H− ions in MgH2 is vital for improving the kinetic performance of MgH2 for hydrogen storage. Herein, a multivalent microenvironment is synergistically created by Mn and Mg2Ni to break the stable structure of MgH2, enabling rapid and stable de/hydrogenation performance.
Ya‐Ke Wu +7 more
wiley +1 more source
ABSTRACT Vanadium oxides are deemed competitive cathode candidates for aqueous zinc‐ion batteries (AZIBs), benefited from their high theoretical capacity and multiple crystalline structures. However, the sluggish reaction kinetics, poor reversibility, and high solubility have hindered the practical application.
Xiaoyu Fan +7 more
wiley +1 more source
目的观察白芍总苷对急性心肌梗死犬微量元素及心肌超微结构的影响。方法取杂种犬30只,随机分为5组(每组6只),分别为模型对照组、阳性对照药物(复方丹参注射液)组,白芍总苷2.0、4.0、8.0mg·kg-1剂量组;采用结扎麻醉开胸犬左冠状动脉前降支(LAD)产生急性心肌缺血模型,观察白芍总苷对微量元素及心肌超微结构的影响。结果与模型对照组比较,白芍总苷组微量元素铜(Cu)含量显著减少 ...
孙明莉 +5 more
doaj
A Study on the Micro Narrative Ability of Primary and Middle School Students' Composition ——A Case Study of Students' Corpus of Grade 3-9 in Xiamen [PDF]
摘要 叙事能力是指一种脱离语境进行有组织表达的语言能力,它是人类语言能力的重要组成部分。书面语叙事能力是语言知识运用的综合体现,目前对这一方面的研究还较为薄弱。本文通过采集分析中小学学生作文语料,得到不同年级、不同学段学生作文微观叙事的实际情况,从叙事的丰富性、流畅性和创造性这三个方面对相关指标进行分析,并提出相应的教学建议。 本文共分七个章节来阐述。第一章为绪论,介绍叙事和叙事能力的基本概念和分类,梳理国内外叙事能力研究的发展现状。从研究对象、研究方法 ...
宋倩
core
Comparison on Security Trading Mechanism and Constructing Our Country’s Mixed Trading Mechanism [PDF]
各种证券交易机制在不同环境下对市场绩效有着不尽相同的影响,并不存在某种证券交易机制相对于其他证券交易机制有着绝对的优势。正因为这样,在设计市场微观结构时,国际上各主要证券市场通行的做法就是采用混合交易机制,以达到优势互补的效果。投资者结构的变化、电子通讯技术的进步亦是推动混合交易机制的发展的重要因素。通过对混合交易机制的比较分析,笔者认为,NYSE的专营商机制模式是一种合理的制度安排。从我国证券市场的实践来看,现行的基于先进电子交易平台的连续竞价交易机制具有撮合交易能力强、能及时释放市场信息等优势。然而,
李尖
core
Effect of Blanching Pretreatment before Drying on the Microstructure and Texture Quality of Dried Apple Slices [PDF]
To improve the drying efficiency and quality of hot air-dried apple slices with blanching pretreatment, this study systematically evaluated the effects of two blanching pretreatments, hot water blanching and vacuum steam pulsed blanching, on the ...
WANG Dong, ZHAO Yifan, DENG Zhining, SUN Haoyuan, WANG Yong, YUAN Yuejin
core +1 more source

