Acquisition of a New-Generation, Variable Pressure, Digital Scanning Electron Microscope for Multi-Disciplinary Studies in Biological Sciences and Biotechnology

采购新一代变压数字扫描电子显微镜，用于生物科学和生物技术的多学科研究

• 批准号: 9512908
• 负责人: Harry Horner
• 金额: $ 8.57万
• 依托单位: Iowa State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-02-01 至 1998-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9512908&HistoricalAwards=false
• 关键词: Acquisition; New; Generation; Variable; Pressure

This proposal requests a new-generation, variable-vacuum (pressure) scanning electron microscope (SEM), for the central Bessey Microscopy Facility (BMF) at Iowa State University, with a digital image enhancement system for observing details more clearly with simple operation using automated functions, and capable of providing high resolution (@ 3.5nm at 30 kV). This instrument can be retrofitted with a cryopreservation system and a x-ray energy dispersive detector already in use in the BMF. Certain modern-day SEMs are able to provide both high-resolution, bright images at high vacuum over a range of kVs and magnifications, and at low vacuums and kVs to reduce specimen radiation damage and charging, but also with good resolution. Need for a high performance, high resolution SEM has become a basic requirement in biological sciences, and in other diverse areas of scientific research. In addition, interest of using SEM at a kV below SkV is also recognized in such applications as studying intracellular ultrastructure, detection and identification of 5-10 nm colloidal gold markers for immunocytochemical labeling with a backscattered detector, and particularly viewing beam sensitive and/or unstable specimens such as food products and other delicate biological samples which cannot withstand high accelerating voltages and beam currents. These latter specimens can be preserved by using quick freezing capabilities such as with a cryopreservation unit and a propane jet freezer already available in the BMF. It is also important to observe with increased resolution surface structures and fracture faces of specimens and, at the same time, to provide x-ray elemental analysis of localized substances within these surfaces. Compositional information and corresponding surface ultrastructure can also be determined and analyzed with a backscattered electron detector. Six specific research projects have been identified on the Iowa State University campus which would directly benefit from a new-generation, high-resolution, and variable-vacuum SEM with the above capabilities. There are a number of other projects that would also benefit from this new-generation SEM by a wide variety of other users of the BMF.

该提案要求为爱荷华州立大学的中央贝西显微镜设施 (BMF) 配备新一代可变真空（压力）扫描电子显微镜 (SEM)，配备数字图像增强系统，通过使用自动化功能的简单操作更清晰地观察细节，并能够提供高分辨率（30 kV 时@ 3.5 nm）。 该仪器可改装为 BMF 中已使用的低温保存系统和 X 射线能量色散探测器。某些现代 SEM 能够在高真空和一定范围的 kV 和放大倍率下提供高分辨率、明亮的图像，并在低真空和 kV 下提供高分辨率、明亮的图像，以减少样品辐射损伤和充电，而且还具有良好的分辨率。对高性能、高分辨率 SEM 的需求已成为生物科学和其他不同科学研究领域的基本要求。此外，在研究细胞内超微结构、使用背散射检测器进行免疫细胞化学标记的 5-10 nm 胶体金标记物的检测和识别，以及特别是观察光束敏感和/或不稳定的样品（例如食品和其他不能承受高加速电压和光束电流的精致生物样品）等应用中，也认识到在低于 SkV 的 kV 下使用 SEM 的兴趣。后者的标本可以通过使用快速冷冻功能来保存，例如 BMF 中已有的冷冻保存装置和丙烷喷射冷冻机。以更高的分辨率观察样品的表面结构和断裂面，同时对这些表面内的局部物质进行 X 射线元素分析也很重要。成分信息和相应的表面超微结构也可以使用背散射电子探测器来确定和分析。爱荷华州立大学校园已确定六个具体研究项目，这些项目将直接受益于具有上述功能的新一代高分辨率可变真空 SEM。 还有许多其他项目也将受益于 BMF 的各种其他用户的新一代 SEM。