【摘 要】
：
一、概述超声波探伤技术用于发电厂管道对接缝质量检验,近年来有了很大的发展。超声波探伤法具有时间快、成本低、对人体无害等优点,特别是对射线探伤法很难发现的危害性缺
论文部分内容阅读
一、概述超声波探伤技术用于发电厂管道对接缝质量检验,近年来有了很大的发展。超声波探伤法具有时间快、成本低、对人体无害等优点,特别是对射线探伤法很难发现的危害性缺陷,如微裂纹、未熔合等有较大的发现灵敏度,所以在应用上日益增多。但是,由于对缺陷的定性和定量方面的解决还不十分完善,如何做到准确而简便地对缺陷定性和定量,仍然是今后需要努力探讨的课题。1 O
First, an overview of ultrasonic flaw detection technology used in power plant pipe seams quality inspection, in recent years has made great progress. Ultrasonic testing has the advantages of fast time, low cost, harmless to the human body, especially the harmful defects which are difficult to be found by the radiographic testing methods, such as the micro-cracks and the unmelted ones. Therefore, increase. However, as the qualitative and quantitative resolution of defects is not yet perfect, how to accurately and easily determine the defects qualitatively and quantitatively still remains to be explored in the future. 1 O
其他文献
根据上海医药站、上海市医药公司、济南医药站、青岛医药站、济宁医药(集团)总公司、淄博医药站、福建省医药公司、福州医药站、厦门医药站、杭州医药站、宁波医药站、金华
语言政策是一个国家历史性、民族性的缩影。语言政策作为一项语言施力载体对一个国家的民族发展与社会和谐至关重要。而社会学概念帕累托最优作为效率与公平的“乌托邦”自然
反复呼吸道感染（ＲＲＩ简称复感）是小儿时期的多发病，近年来发病率有所上升。目前，西医治疗ＲＲＩ初期用抗感冒药，迁延期用左旋咪唑、胸腺肽、转移因子、卡慢舒等。中药治疗小儿ＲＲＩ以个人临床经验
The role of NMR in the pharmaceutical industry has changed dramatically over the lastdecade. Once thought of as an analytical technique used primdrily to suppor
The two-stream instability is common, responsible for many observed phenomena in nature, especially the interaction of jets of various origins with the backgrou
Functionalized benzylic zinc halides reacted with benzaldehydes in the presence of Lewis acid Me3SiCl giving high yields of trans-stilbenes under the catalysis
In this work, DSC and SEM studies indicate that ion-ligand interaction can be utilized to enhance the interaction of poly (styrene-block-2-vinyl pyridine)[P (S-
A 3-D coordination polymer [PbNH(CH2COO)2] 1 has been prepared under hydrothermal conditions and its crystal structure was studied by single-crystal X-ray diffr
The gelating and swelling mechanisms of the hydrogel formed from oxidized konjac glucomannan (OKGM) and chitosan (CS) were studied by Fourier transform infrared
The title compound (C20H30N4O6, Mr = 422.48) was synthesized and its crystal structure was determined by X-ray diffraction method. It crystallizes in the tricli