关键词： Advanced materials   Damage   X-rays   Cross section (Physics)   Resolution (Optics)   Fracture (Materials)   Electronics   Fiber reinforced composites   Computerized tomography   Imaging   Dimensions   Nondestructive evaluation   Ceramics  

摘要： Quality assessment of advanced materials like high strength ceramics and fibre reinforced composites requires detection and characterization of early damage and defects like cracks and pores even with linear dimensions of only 10 μm. Structures of the same size must be distinguishable in components of precision mechanics and electronics. This paper discusses some applications of microfocal X-ray radiography and high resolution computed tomography in nondestructive evaluation of such components. The latter can be looked at as a nondestructive microscopic technique imaging cross sections of an object. Results of investigations using a tomographic unit with a resolution capability of the order of magnitude of 20 μm are presented. ?1990 The American Society of Mechanical Engineers

关键词： 半导体   硅   中子嬗变   掺杂   微结构  

摘要： NTD Si材料与原始单晶硅相比,其缺陷和位错有所增加,特别是EPR缺陷增加显著,电阻率增加20%左右,150(?)·cm以上的电阻率曲线还存在一个较弱的吸收峰值。辐照处理后的NTD Si材料,其点阵常数普遍增大,[111]方向的缺陷明显增多。中照50小时后,局部出现辐照损伤。

关键词： 氧化镁   碳   复合材料   耐火材料   结构  

关键词： Aorta   Basement membrane   Coarctation hypertension  

摘要： To determine the effect of elevated blood pressure on the ultrastructure of rat aorta, hypertension (average mean pressure163 +/- 17 mm Hg) was produced by suprarenal aortic coarctation. After 3 weeks, the subendothelium of the hypertensive thoracicaorta showed significantly increased volume measurements for mononuclear leukocytes and basement membrane-like material comparedwith the sham-operated control group. Focal areas of rarefaction of the subendothelial extracellular material were associatedwith the nearby presence of mononuclear leukocytes. None of these alterations were found in the normotensive abdominal *** tunica media of hypertensive thoracic aorta also contained significantly increased basement membrane-like material. Thisnew finding in an animal hypertension model is the direct result of the quantitative morphological approach employed in thisstudy. In some rats, the partially constricting aortic ligature compromised the right renal artery leading to ischemic atrophyof the right kidney and hyperreninemia in addition to hypertension. In this group, excluded from the previous analysis andevaluated separately, subendothelial thickening and accumulation of basement membrane-like material in the thoracic aortawere greatly increased compared with the control group and other hypertensive rats. This result could not be attributed toan effect of blood pressure alone and might have been caused in part by humoral factors. Basement membrane accumulation appearsto be an important early response of the arterial wall to hypertension or other factors in this rat model.

关键词： ZR   玻璃窑   ZAS   显微结构   窑炉   物理化学  

摘要： 由陕西省硅酸盐学会和机械电子工业部成阳四四○○厂共同组织的《四四○○厂屏玻璃窑用ZAS、ZR系列耐火材料使用后显微结构物理化学及窑炉相关技术研究》应用理论研究课题,于1989年12月22日通过成果鉴定。四四○○厂屏玻璃窑是由日本引进的大型玻璃熔炼设备,自投产共运行了六年零四个月。为了逐步减少屏玻璃窑用耐火材料的进口量,提高耐火材料的国产化程度。陕西省硅酸盐学会同四四○○厂于1987年8月27日签订了立题协议。学会利用多学科、多部门、人才集中、设备配套横向联合攻关的优势,组织力量,对我国第一座引进的大型屏

关键词： 复合耐火材料   显微结构   强度   碳  

关键词： 水泥   熟料   显微结构   硅酸盐  

摘要： 本文研究了用TAS Plus图像分析仪对水泥熟料显微结构矿相进行定量分析的方法,提出用蒸馏水作水泥熟料光片的浸蚀剂,并找出了不同矿相的浸蚀条件。浸蚀出来的光片试样能较好地满足各矿相分别定量的要求。根据水泥熟料纤维结构特征编写矿相定量分析程序,可获得准确的分析数据。

关键词： Technology   Ultrafine   atom probe field ion microscopy   Materials   microtectonics   Irradiation   Atomicity   Ion microscopy  

摘要： Atom probe field-ion microscopy (APFIM) is well suited to the microstructural characterization of the ultrafine-scale features that are formed in materials during irradiation. The atomic spatial resolution of this technique permits a complete microstructural and chemical description of the ultrafine features that control the mechanical properties to be made. A description of the technique and the types of analyses that may be performed are presented. © 1989 The Metallurgical Society of AIME.

关键词： SiC-TiB2   粒子复合物   显微结构