1 自适应光学全国重点实验室,四川 成都 610209
2 中国科学院光电技术研究所,四川 成都 610209
3 中国科学院大学,北京 100049
4 山东高等技术研究院,山东 济南 250100
Overview: Gravitational waves are spacetime oscillations radiated outward by accelerating mass objects. Significant astronomical events in the universe, such as the merging of massive black holes, emit stronger gravitational waves. Detecting gravitational waves allows for a deeper study of the laws governing celestial bodies and the origins of the universe, making accurate detection crucial. Gravitational wave detection technology utilizes Michelson interferometers to convert the extremely faint spacetime fluctuations caused by gravitational waves into measurable changes in optical path length. Recently, ground-based large Michelson interferometers have achieved direct detection of high-frequency gravitational waves. However, the detection of low-frequency gravitational waves, which is equally important, is not feasible on the ground due to arm length and ground noise issues. This necessitates the construction of ultra-large Michelson interferometers in space for low-frequency gravitational wave detection. Spaceborne gravitational wave detection telescopes play a vital role in collimating bidirectional beams in ultra-long interferometric optical paths in space. The extremely subtle changes in optical path caused by gravitational waves impose high demands for pm-level optical path length stability and below 10?10 level backscattered light in these telescopes. The ultra-high level index requirements exceed the precision limits of current ground testing techniques for telescopes. To ensure that spaceborne telescopes maintain their ultra-high design performance in the orbital environment, developing testing and evaluation techniques for these key indicators is a crucial prerequisite for the success of the space gravitational wave detection program. This paper provides an overview of the development of spaceborne gravitational wave detection telescopes, both domestically and internationally. It focuses on the current status and some test results of optical path length stability and backscattered light testing of telescopes under development, as well as further testing plans, providing a reference for the testing and evaluation of Chinese space gravitational wave detection space-borne telescopes.
空间引力波探测 星载望远镜 地面测试 光程稳定性 后向杂散光 space gravitational wave detection spaceborne telescope ground test optical path length stability backscattered light
安徽农业大学生命科学学院, 安徽 合肥 230036
利用SRAP分子标记, 从88对引物中筛选出34对引物组合, 分析砀山酥梨母本与授粉品种之间的亲缘关系, 探讨梨授粉品种亲缘关系对砀山酥梨石细胞含量的影响。结果表明: 授粉品种紫酥、鸭梨和马蹄黄与砀山酥梨亲缘关系较远, 授粉品种华山、幸水和圆黄与砀山酥梨亲缘关系较近; 砀山酥梨自然授粉果实石细胞含量为0.61%; 选用紫酥、鸭梨和马蹄黄作授粉树时, 果实石细胞含量分别为0.34%、0.33%、0.36%, 低于自然授粉的砀山酥梨; 选用华山、幸水和圆黄作授粉树时, 果实石细胞含量分别为0.84%、0.70%、0.66%, 高于自然授粉的砀山酥梨。选用与砀山酥梨亲缘关系较远的梨品种作授粉树可减少砀山酥梨石细胞含量, 改善口感。
砀山酥梨 亲缘关系 石细胞 Dangshansu pear genetic relationship stone cell SRAP SRAP
贵州大学 材料与冶金学院贵州省材料结构与强度重点实验室,贵州 贵阳 550003
对核聚变反应堆用低活化马氏体钢进行了激光焊接试验,并对焊接接头的显微组织和力学性能进行了测试分析。结果表明,对低活化马氏体钢进行激光焊接可以获得高质量的焊接接头;焊缝组织主要为板条状马氏体,硬度可达530 HV;热影响区(HAZ)包括粗晶区和细晶区,粗晶区为粗大的珠光体,细晶区为细小的珠光体和铁素体的混合组织,最低硬度为220 HV;焊接接头有很好的力学性能,抗拉强度高达775 MPa。
激光技术 激光焊接 低活化 马氏体钢 显微组织 力学性能