排序方式: 共有5条查询结果,搜索用时 15 毫秒
1
1.
核素内放疗已越来越多应用于临床,预测、增敏其疗效具有实际应用价值.本研究对荷S180瘤小鼠在32p肿瘤间质内注射治疗前行99mTc-HL91乏氧显像,并用Carbogen吸入进行乏氧干预,结果显示99mTc-HL91肿瘤滞留量在Carbogen吸入后明显减少,同时32p肿瘤间质内注射治疗后Carbogen吸入组小鼠肿瘤大小明显小于空气吸入组;但是,99mTc-HL91肿瘤滞留量多少与32p肿瘤间质内注射治疗后肿瘤大小间无明显相关性.说明99mTc-HL91乏氧显像可以反映乏氧干预效果,但不能预测32p肿瘤间质内注射治疗疗效,而Carbogen吸入可以提高32P肿瘤间质内注射治疗疗效. 相似文献
2.
在国内首台摩擦叠焊设备上实现了2024铝合金/2024铝合金摩擦液柱成形(FHPP)连接,金属棒消耗段的直径为14mm,预钻孔深为25mm,孔径为16mm,主要研究了转速和保护气体对FHPP成形质量的影响,通过金相显微镜、显微硬度仪等测试手段分析了试样的微观组织性能.结果表明,转速过低导致母材和金属棒无法接合甚至出现马达不能正常工作现象,采用转速为5 000 r/min,进给速度为O.5 mm/s的组合,可得到较好的焊缝;施加保护气体能更进一步改善FHPP的成形质量,接合线较未加保护气体时明显细化,金属棒上端材料和母材达到了良好接合.Abstract: The cylindrical coupling of 2024 Aluminum alloy was welded by friction hydro pillar processing (FHPP) in the first domestic friction stitch welding machine. The diameter of the consumed metal stud is 14 mm, the depth and diameter of the predrilled hole are 25 mm and 16 mm respectively. The effects of rotational speed and shielding gas on the FHPP quality were mainly studied, and the microstructure and its properties of the sample were analyzed by means of some measuring apparatus such as optical microscope and microhardness tester etc. The results indicate that the low rotation can form the insufficient bonding, even result in the cease of the weld head motor during the welding. The quality of welded joint is better when the rotational speed is 5 000 r/min and the feeding rate is 0.5 nan/s. The shielding gas can improve the quality of FHPP with thinner fusion line, and the upper part of the metal stud is bonded to the base metal very well. 相似文献
3.
文中结合当前海洋油气开采作业的发展现状与趋势,简述了高效率的海管铺设系统和主要铺设方法,介绍了海洋工程应用中的钨极氩孤焊、熔化极气体保护焊、激光-电弧复合焊以及电子束焊。根据国内外水下焊接技术发展要求和应用现状,提出了基于CAN总线的海底管线自动焊接系统,为实现深水管线全自动焊接打下了基础。 相似文献
4.
5.
1