关键词： 纤维材料   增强纤维   衍射花样   复合材料   取向性   晶态   射线衍射   显微结构  

摘要： 前言纤维种类很多,通常用于制作复合材料的有玻璃纤维、碳纤维、硼纤维、碳化硅纤维以及各种有机合成纤维等。纤维与一般金属材料不同,它有独特的组织结构。目前高级复合材料用的增强纤维,

关键词： 滤光片   底片   代表   照片   扫描电镜   金相学   显微结构   电子探针   电子光学仪器  

摘要： 彩色分类金相学是不同于一般的彩色金相学,不能用光学显微镜进行观察而只能用特殊的设备如扫描电镜或电子探针将试样的结构特征先拍成黑一白底片,然后配合原色滤光片,并指定某一原色来代表某一相或特征,再依次翻拍在同一张彩色底片上以制成一张“彩色复合照片”。单从这一张照片就能够看到试样所反映出的所有信息。本文列举两个典型例子来说明这种彩色分类金相的操作方法和应用,同时在所举的例子中还列出一种叫做“电压对比方法”用以控制半导体器件或集成电路的质量。本篇报导的目的,希望引起读者对这一较新的发展的注意及在国内开展这方面的工作。

关键词： 石墨化焦   非晶质   抛光面   偏光   离子轰击   显微结构   微晶   晶体   碳材料  

摘要： 材料的性能与其结构是密切相关的,因此人们试图用各种方法去查明材料的结构特性,而显微镜法就是其中的一种。但供显微镜检验的碳材料试样,尤其是石墨材料试样,在机械抛光过程中抛光面上总要形成一层薄薄的非晶

关键词： 钨基复合材料   液相烧结   显微结构   机械性能   力学性质  

摘要： 在“斯堪的纳维亚冶金学报”一九七六年第四期上,发表了瑞典国防部研究局的L。艾克勃姆的著名文章《液相烧结钨基复合材料的显微结构对机械性能的影响》,内容摘要如下。添加镍、铁的钨基复合材料(90～95%W/7～3.5%Ni/5～1.5%Fe)系用细晶粒

摘要： An exploding wire system has been used to examine the effects of microstructure on the dynamic fracture behavior of high purity iron, 0.2% C steel and free machining steels. Optical and scanning electron microscopy studies of the fractured specimens indicate that the dynamic loading response is strongly material dependent, being inlfuenced by the grain size and the presence of brittle second phase particles. Predominantly intergranular microcracks are observed in pure iron specimens having grain sizes ranging from 40 to 200 microns, whereas transgranular microcracks are observed to initiate the fracture process in 0.2% C steel of varying microstructures. The degree of dynamic fracture increases with increasing grain size in 0.2% C steel containing ferrite - pearlite microstructures. A detailed study of dynamically loaded specimens indicates that the occurrence of microfractures in 0.2% C steel is associated with second phase particles in the form of inclusions and carbides, and that the predominance of intergranular cracking in pure iron is due to its relatively low carbon content and coarse grain size. The fracture characteristics of the various materials are compared and discussed in relation to the dynamic fracture behavior of steel subjected to other methods of loading.

关键词： 显微结构   干涉   彩色照片   石墨化   碳素材料  

摘要： 在碳素材料的理化检验中,研究碳素材料的显微结构的特征具有重要的意义。本文介绍部分碳素材料在灵敏色调(色干涉)下的显微结构的彩色照片,并以此来说明它们的结构特征。试验条件:应用大型卧式金相显微镜(Neophoto),光源采用碳棒弧光源,经紫外滤光器,并用RI灵敏色片产生灵敏色调照明,采用国产GB—17°彩色胶卷摄照,彩色正片采用放大印制法。试样制备接一般金相试样的要求,经磨制、粗抛和精抛光而成,对于粉状、粒状及结构

关键词： Neurosecretion   Harvestman   Exocytosis   Release   Ultrastructure  

摘要： The paraganglionic plates of the harvestman, Trogulus, are neurohemal organs composed of a thick neural lamella facing a blood sinus, basal glial cells, and seven distinct types of axon terminals (A1, A2, B1, B2, B3, B4 and C) identified on the basis of elementary granule size, electron density, and structure of *** release of A1 type granules occurs by exocytosis into the extraaxonal space below the acellular neural lamella. The release of the content of C granules occurs after fragmentation into small electron dense vesicles. Clusters of these vesicles intermixed with clear vesicles pressing against the axolemma beneath the neural lamella, apparantly correspond to the sites of release.

关键词： Rare earths   Lanthanides   Recycling   Extractive metallurgy   Magnets   Catalysts   BatteriesPreview | Abstract | Full Text | PDF (449 KB) | FiguresNovember 18   2013G A MoldoveanuG A Moldoveanu   V G PapangelakisV G PapangelakisMoldoveanuMoldoveanu   PapangelakisPapangelakisMoldoveanu et al.Moldoveanu et al.Leaching of lanthanides from various weathered elution deposited oresLeaching of lanthanides from various weathered elution deposited oresG A MoldoveanuG A Moldoveanu   V G PapangelakisV G PapangelakisMoldoveanuMoldoveanu   PapangelakisPapangelakisMoldoveanu et al.Moldoveanu et al.Volume: 52   Issue: 3   pp. 257–264http://***/10.1179/1879139513Y.0000000060Keywords: Ion adsorption clays   Rare earths leaching   Rare earths desorption   Ion exchange leaching   Lanthanides   Rare earth elements Preview | Abstract | Full Text | PDF (314 KB) | FiguresNovember 18   2013D K ChibweD K Chibwe   G AkdoganG Akdogan   C AldrichC Aldrich   P TaskinenP TaskinenChibweChibwe   AkdoganAkdogan   AldrichAldrich   TaskinenTaskinenChibwe et al.Chibwe et al.Modelling of mixing   mass transfer and phase distribution in a Peirce–Smith converter modelModelling of mixing   mass transfer and phase distribution in a Peirce–Smith converter modelD K ChibweD K Chibwe   G AkdoganG Akdogan   C AldrichC Aldrich   P TaskinenP TaskinenChibweChibwe   AkdoganAkdogan   AldrichAldrich   TaskinenTaskinenChibwe et al.Chibwe et al.Volume: 52   Issue: 2   pp. 176–189http://***/10.1179/1879139512Y.0000000056Keywords: Computational fluid dynamics   Peirce–Smith converter   ModellingPreview | Abstract | Full Text | PDF (536 KB) | FiguresNovember 22   2013D K ChibweD K Chibwe   G AkdoganG Akdogan   C AldrichC Aldrich   P TaskinenP TaskinenChibweChibwe   AkdoganAkdogan   AldrichAldrich   TaskinenTaskinenChibwe et al.Chibwe et al.Modelling of mixing   mass transfer and phase distribution in a Peirce–Smith converter modelModelling of mixing   mass transfer and phase distribution in a Peirce–Smith converter modelD K ChibweD K Chibwe   G AkdoganG Akdogan   C AldrichC Aldrich   P TaskinenP TaskinenChibweChibwe   AkdoganAkdogan   AldrichAldrich   TaskinenTaskinen  

摘要： Polycrystalline materials are visualized in this paper as a statistical ensemble of microelements whose crystallographic axes are randomly, but not uniform randomly, oriented in the material system. Based on this concept the influence of internal dislocations and grain boundaries on the elastic response of such metals is discussed. The latter influence is taken into consideration by combining the grain boundary coincidence cell models of Bollmann with the relaxation technique of Weins in the case of symmetric tilt boundaries. The micromechanics theory of Axelrad and Provan is also briefly discussed to indicate where these quantitative metallurgical studies are of importance in the further development of this theory. Résumé Dans cette étude, les matériaux poly cristallins sont considérés comme un ensemble statistique de micro-éléments dont les axes cristallographiques sont orientés au hasard, mais non uniformément, dans le matériau. A partir de ce concept, les auteurs discutent de l'influence de dislocation et des joints de grains sur la réponse élastique de tels métaux. L'influence des joints de grains est considérée en combinant le modéle des sites en coincidence de Bollmann avec la technique de relaxation de Weins, pour le cas des joints de flexion symétriques. La théorie de la micromécanique de Axelrad et Provan est aussi brièvement discutée pour indiquer quelles sont les études métallurgiques quantitatives nécessaires au développement ultérieur de cette théorie.

关键词： Public Health   Collagen   Sodium   Basement Membrane   Cataract  

摘要： The peripheral exfoliation band was scraped from seventeen lenses that were removed because of senile cataract. A suspension of the exfoliation substance, negatively stained with sodium silicotungstate, was studied and compared with the sectioned exfoliation *** is concluded that the exfoliation substance probably consists of a collagen material, that perhaps comes from basement membranes.