Energy dispersive X-ray transmission imaging and coherent scatter tomography

能量色散X射线透射成像和相干散射断层扫描

• 批准号: 2277225
• 金额: --
• 依托单位: University College London
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2019
• 资助国家: 英国
• 起止时间: 2019 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2277225
• 关键词: Energy; dispersive; ray; transmission; imaging

Key Objectives and Aims of the ResearchX-ray imaging is a key technique used in many fields such as medical diagnostics, quality control and materials testing, permitting the investigation of otherwise opaque volumes. 3D images can be produced by taking many flat X-ray images and performing a process known as computed tomography (CT) reconstruction. This project aims to develop a 3D imaging technique that, unlike normal X-ray imaging, discriminates different materials based on how they scatter X-rays. A sample is illuminated by a narrow beam of X-ray and 'off-axis' measurements recorded the scattering profile. Features are observed in the scattering profile which depend on the atomic structure of material due to a phenomena known as X-ray diffraction (XRD). Since every material has a different structure, the profile can be used as a fingerprint to identify unknowns. Ultimately, by applying the same CT reconstruction process, this technique can provide a 3D map of any volume of interest to determine what materials are present and where they are located.Novel ScienceCurrent approaches to XRD CT involve a lengthy process of making individual point measurements as the sample is translated and rotated. The novel aspect of this project is to develop this technique further to reduce scan times. This will be through a combination of implementing multi beam techniques and sparse data collection strategies. The student will use a cutting edge X-ray detector (HEXITEC) which will enable the most efficient data collection, removing the need for the slow sample translation step. The data produced will be complicated and the student will also develop software to organise, interpolate and reconstruct the spatially resolved scattering profiles in 3D.Potential ApplicationsThe technique has the power to provide 3D spatially resolved material identification. This has wide ranging potential in the following application areas:Analysis of excised tissue at the time of cancer surgery to ensure that all diseased tissue has been removed. Patients who, post-surgery, are discovered to have had insufficient tissue removed are at greater risk of recurrence and may require further treatment (i.e. additional cost to the health care provider and increased patient anxiety).Drug, explosive and contraband detection in security screening where the layout and content of baggage (for example) is unknown.Defect identification in manufacturing processes. For example, in composites fabrication there is a need to identify voids, inclusions and resin rich areas which could lead to structural failure.In the meat industry there is a requirement to identify foreign objects or damaged products for food safety. There is also a shift towards using technology to digitally grade products in order to increase yield (increasing economic value) and reduce waste (reducing environmental impact).

研究的主要目的和目标X 射线成像是医疗诊断、质量控制和材料测试等许多领域使用的关键技术，可以对不透明的体积进行研究。 3D 图像可以通过拍摄许多平面 X 射线图像并执行计算机断层扫描 (CT) 重建过程来生成。该项目旨在开发一种 3D 成像技术，与普通 X 射线成像不同，该技术根据 X 射线的散射方式来区分不同的材料。样品被窄束 X 射线照射，“离轴”测量记录了散射轮廓。由于 X 射线衍射 (XRD) 现象，在散射剖面中观察到的特征取决于材料的原子结构。由于每种材料都有不同的结构，因此轮廓可以用作识别未知物的指纹。最终，通过应用相同的 CT 重建过程，该技术可以提供任何感兴趣体积的 3D 图，以确定存在哪些材料以及它们的位置。新颖科学当前的 XRD CT 方法涉及进行单个点测量的漫长过程，如下所示：样品被平移和旋转。该项目的新颖之处在于进一步开发该技术以减少扫描时间。这将通过结合实施多波束技术和稀疏数据收集策略来实现。学生将使用最先进的 X 射线探测器 (HEXITEC)，它将实现最高效的数据收集，从而无需缓慢的样本平移步骤。生成的数据将很复杂，学生还将开发软件来组织、插值和重建 3D 空间分辨散射剖面。潜在应用该技术能够提供 3D 空间分辨材料识别。这在以下应用领域具有广泛的潜力：分析癌症手术时切除的组织，以确保所有患病组织均已被去除。手术后发现组织切除不足的患者复发的风险更大，可能需要进一步治疗（即医疗保健提供者的额外费用和患者焦虑的增加）。安全检查中的毒品、爆炸物和违禁品检测例如，行李的布局和内容未知。制造过程中的缺陷识别。例如，在复合材料制造中，需要识别可能导致结构故障的空隙、夹杂物和富含树脂的区域。在肉类工业中，需要识别异物或损坏的产品以确保食品安全。人们还转向使用技术对产品进行数字分级，以提高产量（增加经济价值）并减少浪费（减少环境影响）。