High-Performance Transparent Optical Ceramic Scintillators through Nanotechnology

采用纳米技术的高性能透明光学陶瓷闪烁体

基本信息

批准号：
7327556
负责人：
ALEXANDER LEMPICKI
金额：
$ 14.45万
依托单位：
RADIATION MONITORING DEVICES, INC.
依托单位国家：
美国
项目类别：
财政年份：
2007
资助国家：
美国
起止时间：
2007-08-01 至 2008-07-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7327556
关键词：
Aluminum Oxide Alzheimer&apos s Disease Area Biological Biological Process Body Image Carbon Isotopes Ceramics Cereals Characteristics Collaborations Condition Coupled Craniocerebral Trauma Cytoplasmic Granules Dependence Development Diagnosis Digital Radiography Dimensions Disease Dose Equipment Fluorine Functional Imaging Future Gamma Rays Goals Growth High temperature of physical object Image Imaging Techniques Investigation Joint Ventures LSO crystal Label Lead Life Light Lutetium Malignant Neoplasms Measures Medical Methods Mind Modification Monitor Nanotechnology Nature Nitrogen Nuclear Optics Output Oxygen Particle Size Performance Phase Photons Play Porosity Positron Positron-Emission Tomography Powder dose form Procedures Process Property Range Rate Reporting Reproducibility Research Residual state Resolution Role Source Specimen Staging Stroke Structure Symptoms System Techniques Technology Temperature Time Tracer Tube Visible Radiation Work clinical Diagnosis cost cost effective design desire detector experience gadolinium sulfoxylate improved in vivo instrument instrumentation interest mathematical model nanoparticulate nanopowder nanoscale novel strategies photomultiplier prevent research study response size

项目摘要

DESCRIPTION (provided by applicant): LSO is generally recognized as the ideal scintillator for PET. It has high stopping power for 511 keV gamma rays, high light yield of over 20000 photons/MeV, and rapid decay of 32 ns. It achieves high coincidence timing resolution and energy resolution. But single crystals of LSO are difficult and expensive to grow, reproducibility is poor, and the material is simply not available for general commercial use. To overcome these drawbacks, we have in our previous work developed a translucent LSO optical ceramic, which displays scintillation performance comparable to that of the single crystal, yet is easier to fabricate and could fill the availability gap at lower cost. But because LSO is optically anisotropic, it cannot be made fully transparent by conventional ceramic technology. Recently, however, a new process has been developed through nanotechnology that is capable of achieving virtually full transparency in ceramics of even optically anisotropic materials. The technique involves the consolidation of nanopowders under conditions that limit the ultimate grain sizes to below the wavelengths of visible light, thereby preventing virtually all scattering and rendering the material fully transparent. The procedure has been completely confirmed in experiments on polycrystalline alumina, which is similarly anisotropic, and is being developed for optical window applications. It is the aim of this proposal to combine the two already developed technologies so as to produce LSO in the form of a fully transparent optical ceramic, which displays scintillation performance comparable to that of a single crystal. In Phase I we will confirm that the process that has already been established for alumina is adaptable to LSO as well. We will establish techniques to fabricate the necessary nanoparticulate powders and to define the consolidation conditions under which the desired material properties can be achieved.

描述（由申请人提供）：LSO 被普遍认为是 PET 的理想闪烁体。它对 511 keV 伽马射线具有高阻止本领、超过 20000 光子/MeV 的高光产额以及 32 ns 的快速衰减。它实现了高重合时间分辨率和能量分辨率。但LSO单晶生长困难且昂贵，重现性差，而且该材料根本无法用于一般商业用途。为了克服这些缺点，我们在之前的工作中开发了一种半透明的 LSO 光学陶瓷，它具有与单晶相当的闪烁性能，但更容易制造，并且可以以更低的成本填补可用性空白。但由于 LSO 具有光学各向异性，因此无法通过传统陶瓷技术使其完全透明。然而，最近通过纳米技术开发了一种新工艺，即使是光学各向异性材料的陶瓷也能够实现几乎完全透明。该技术涉及在将最终晶粒尺寸限制在可见光波长以下的条件下固结纳米粉末，从而防止几乎所有散射并使材料完全透明。该过程已在多晶氧化铝的实验中得到完全证实，多晶氧化铝同样具有各向异性，并且正在为光学窗口应用而开发。该提案的目的是结合两种已开发的技术，以生产全透明光学陶瓷形式的LSO，其闪烁性能可与单晶相媲美。在第一阶段，我们将确认已经为氧化铝建立的工艺也适用于 LSO。我们将建立技术来制造必要的纳米颗粒粉末，并确定可以实现所需材料性能的固结条件。