micro computed tomography methodology and applications pdf creator

Micro Computed Tomography Methodology And Applications Pdf Creator

On Monday, December 28, 2020 2:57:38 AM

File Name: micro computed tomography methodology and applications creator.zip
Size: 2758Kb
Published: 28.12.2020

Such as real- time x- ray imaging cone beam ct scan pdf converter or pdf cone- beam CT.

Cone beam ct scan pdf converter

Refworks Account Login. Open Collections. UBC Theses and Dissertations. Featured Collection. Mark Martinez, Chemical and Biological Engineering Additional Examiner Committee Page iii Abstract A research program was undertaken to visualize and quantify the three-dimensional nature of fabric and microstructure of natural silts with the objective of better understanding the influence of these factors on macroscopic monotonic and cyclic soil behaviour.

The development of technology for the visualizations using X-ray micro-computed tomography CT formed a key task.

Natural, low-plastic Fraser River Delta silt available from the Lower Mainland area of British Columbia was used as the geomaterial for the study. In order to capture a representative elemental volume for analysis in micro-CT, experimentation was undertaken to identify the appropriate method s to obtain sub-samples of specimens from relatively larger undisturbed samples or reconstituted specimens of silt.

Thin-walled 0. The potential for sample preservation using resin impregnation was also explored. A very low viscosity resin which cured at room temperature under anaerobic conditions provided a novel way to successfully preserve samples. Preliminary observations suggest that there is minimal disturbance to the internal fabric and microstructure within the core of the specimen sub-samples. A collaboration with three X-ray micro-CT laboratories allowed for scanning of the silt sub-samples to voxel resolutions ranging from 0.

The three-dimensional datasets were then post-processed using commercially available software. Particle segmentation of the images was undertaken using the watershed methodology, which led to successful digital grain size distribution matching with typical laboratory data. Initial quantitative analysis indicates that the void ratio as well as particle contact angle distribution diagrams can be formulated for silt-sized material.

Quantification of particle shape including sphericity, roundness, and aspect ratio, and their relation to specimen mineralogy, was also explored. The research work demonstrated that X-ray micro-CT technology has a strong potential to be a viable method for three-dimensional visualization of silts.

Soils retrieved directly from the field with little disturbance seem to show results that are different from those obtained from laboratory-prepared specimens. These observed differences in soil behaviour can be attributed partially to the physical arrangement of particles fabric and microstructure of the tested soils. Research in quantifying these phenomena specifically is very limited; especially with respect to soils such as silts that have small particle sizes.

A good understanding of the mechanical behaviour of silts is critically important for geotechnical engineering design. This thesis presents a new methodology for preparing silt specimens for three-dimensional, non-destructive X-ray micro-computed tomography, proving that there is potential for this technology to qualitatively and quantitatively assess the microscopic fabric and structure of silts.

I, Michelle Wesolowski, along with assistance from Ana Valverde, was involved in the preparation of soil specimens for the purpose of sub-sampling for X-ray micro-CT analysis. All laboratory and computational experimentation were conducted under the supervision of Dr. Wijewickreme, who also reviewed and provided technical and editorial input for completion of the final manuscript. Acknowledgement of respective authors for reproduced figures and data is given throughout the dissertation.

All other figures and data presented were prepared by the current author. No natural varving noted in the reconstituted specimen John, I learned so much more than I could have expected during my time in Vancouver, and I will certainly carry his insights with me throughout my career as a geotechnical engineer.

I would also like to thank Otman Abida for his enthusiasm and support in the Environmental Lab, whose knowledge and expertise helped immensely in setting up the resin impregnation process.

Many thanks must also be made to Dr. Sadana Dilrukshi for her helpfulness and patience at the beginning of this project. Truly, thank you very much for all of the hours dedicated to helping in this research.

I also wish to thank my fellow researchers in the Geotechnical Lab for all of the great memories that we made together. I am looking forward to our paths crossing soon. Thank you, Ana Valverde, for your advice and partnership as we embarked on this project together. Finally, I must thank my family and my boyfriend, Phillip Cooper, for their unwavering support throughout this entire process. Dedication 1 1. As such, specific focus has been placed on low-plastic silty soils in the Lower Mainland area of British Columbia.

Fraser River Delta silts in particular have been the focus of research at the University of British Columbia for over 18 years. In this work, the monotonic and cyclic shear behaviour of relatively undisturbed and reconstituted slurry deposited silts has been investigated using a variety of methods including laboratory direct simple shear and triaxial testing.

Several factors, including effective confining stress, over-consolidation ratio, coarse-grained fraction, initial static shear bias, soil plasticity, and fabric and microstructure, have been shown to affect the behaviour of silts Wijewickreme et al.

A breadth of past soil mechanics and geotechnical engineering research has shown that the fabric and microstructure e. Research addressing this regime specifically with respect to silt has been limited Wijewickreme et al. In addition to this, many researchers have demonstrated that in sands, significant particle reorientation occurs during consolidation, notably that the long axis of the particle tends to align itself more perpendicular to the applied load as the load increases Paniagua et al.

Observations of particle sphericity and aspect ratio have also known to cause varying changes in sample fabric and microstructure Yang et al. The true microscopic 2 fabric and structure of undisturbed silt specimens compared to slurry deposited silt specimens has never been explicitly explored. The above has demonstrated that there is a lack of investigation in fabric and microstructure of low-plastic silt material.

Representative quantification of fabric and microstructure of fine-grained materials has been limited due to many constraints — including the difficulties in not disturbing the fabric and microstructure during sampling and specimen preparation.

Optical microscopy and scanning electron microscope SEM technologies have been used in the past, however these methods are restricted to a two-dimensional plane of viewing Reyes et al. Fabric and microstructure are inherently three-dimensional due to the complex shapes, arrangements, and orientations of particles and voids. The ability to capture a representative reconstruction of full, individual particles is restricted by the scanning resolution, or voxel size.

Research specifically on silt for the application to geotechnical engineering is extremely limited to non-existent. Previous two-dimensional imaging techniques have failed to capture the undisturbed specimen fabric and microstructure which is contributing to the silt behaviour, further reaffirming the need for X-ray micro-computed tomography analysis. There is currently no simple best-practice process for preparing, imaging, and processing silt specimens with the intention of analyzing their particle characteristics and influence on monotonic and cyclic shear behaviour.

If the above were to be successful, a methodology could be developed for classifying silt behaviour to its fabric and microstructure.

Eventually, samples could be extracted from the field, preserved, and sent immediately to the X-ray micro-computed tomography scanner for analysis which would reveal preliminary estimates of soil behaviour based on the observed fabric and microstructure. Chapter 1. It highlights that X-ray micro-computed tomography is the next frontier for non-destructive three-dimensional imaging in this regard. Chapter 2. It also reviews the definitions of fabric and structure, as well as several aspects of particle shape.

Sample preservation methods, imaging techniques for geomaterials, and image processing software are presented. Chapter 3. It outlines the material tested, the systematic study of sampling tube shape and material, specimen preparation, and experimental resin impregnation methods. It also summarizes the testing program, including all of the specimen types that were prepared for imaging. Chapter 4. Chapter 5. A summary and conclusion of final results, in conjunction with recommendations for future research are made in Chapter 6.

The background from this mechanical understanding has been the motivation behind this research for observing and analyzing the three-dimensional particle fabric and structure at the microscopic level.

The literature review presented in this chapter introduces the considerations relating to particle fabric and structure and its applications to silt behaviour. Section 2. Finally, Section 2.

FitzPatrick reviewed several definitions of fabric and structure, comparing the Oxford English Dictionary definition to German soil scientist translations, dating back to 6 the s.

In their book on clay microstructure, Bennett and Hulbert make references to pioneering works by Terzaghi, Casagrande, Lambe, and Mitchell, highlighting that the concepts of fabric and structure have been a point of keen interest to geotechnical engineering applications for nearly a century.

Fabric, with respect to soils, is defined as the spatial arrangement of solid particles and voids. Fabric focuses primarily on the characteristics of individual particles such as shape and size, and how this has led to their particulate arrangement FitzPatrick, ; Santamarina, Oda described that there are two main components to fabric, which are listed below and shown schematically in Figure 2.

The primary directional vector of each grain is plotted in a form of polar histogram to quantify changes or patterns in particle orientation.

In order to quantify the relative configuration of particles, the coordination number CN is often used, which is 7 the number of adjacent particles that are in physical contact with a single particle.

Particle contact area is also investigated. The aspect ratio AR is used to describe shape and is defined as the ratio of the smallest diameter to the largest diameter of a particle Equation 2. An AR of 1. This can include the fluid or gas that infills these pores, as well as the chemical or electrostatic bonding that may exist between individual soil particles Craig, ; Chang et al.

Types of soil structure include single-grained, blocky, columnar, platy, and massive Engle et al. Soil structures are often classified in hydropedology and groundwater management by their ability to pass water Engle et al.

Single-grained structure has rapid flow, whereas blocky and columnar structure has moderate flow, and platy and massive structure has slow flow. Clays can also display a wide range of structure types such as dispersed, card house, and deflocculated Figure 2.

Problem soils such as these showcase the need for research into soil structure to further understand their failure mechanisms. While this research will focus on silt-sized materials, it is important to recognize that soil specimens contain a wide range of particle sizes and fines, and therefore, these structures may be present under a given real-life situation. Microstructure of clays has also been classified by Hight and Leroueil as observing the void ratio, the strength, and the yield stress of an intact specimen as a whole.

This thesis is specifically concerned with silt-sized materials, defined here as particles passing the No. As such, specimen investigation occurs at the micro-scale The above review demonstrates the complex link between fabric and microstructure.

Depending on the scale of research and investigation, it may be necessary to analyze both components. Certain aggregations of particle types and textures may be indicative of depositional environment and energy.

For example, aeolian deposits, such as sand dunes, often have very well-rounded, spherical soil particles. Glacial sediments may have striations due to scraping at the glacier base and be deposited with their long axis in the orientation of glacial movement.

Cone beam ct scan pdf converter

Refworks Account Login. Open Collections. UBC Theses and Dissertations. Featured Collection. Mark Martinez, Chemical and Biological Engineering Additional Examiner Committee Page iii Abstract A research program was undertaken to visualize and quantify the three-dimensional nature of fabric and microstructure of natural silts with the objective of better understanding the influence of these factors on macroscopic monotonic and cyclic soil behaviour. The development of technology for the visualizations using X-ray micro-computed tomography CT formed a key task. Natural, low-plastic Fraser River Delta silt available from the Lower Mainland area of British Columbia was used as the geomaterial for the study.

3D XRM for Material Science

Bruker 3D X-ray Microscopes XRM combine micro-computed tomography micro-ct hardware with specialized software into a complete microscopic visualization solution. Ranging from micro-resolution benchtops to nano-resolution floor standing instruments, Bruker XRM solutions provide the perfect balance of ease-of-use and power. From measuring the porosity in geological specimens to the thickness of multiple coatings on pharmaceutical tablets or the on-chip and board level interconnect structure of circuits, XRM allows rapid multiscale analysis. The non-destructive nature of XRM allows validation of component integrity bringing QC of manufacturing techniques such as additive manufacturing to a new level. Reconstruction is accomplished with the latest GPU driven algorithms providing results from large datasets in a fraction of the time.

New Search. E-Journal Titles. Database Titles. Interlibrary Loan.

It particularly highlights the scanning procedure, which represents the most crucial step in micro CT, and discusses in detail the reconstruction process and the artifacts related to the scanning processes, as well as the imaging software used in analysis,. Written by international experts, the book illustrates the application of micro CT in different areas, such as dentistry, medicine, tissue engineering, aerospace engineering, geology, material engineering, civil engineering and additive manufacturing. Covering different areas of application, the book is of interest not only to specialists in the respective fields, but also to broader audience of professionals working in the fields of imaging and analysis, as well as to students of the different disciplines. Skip to main content Skip to table of contents. Advertisement Hide.

Refworks Account Login. Open Collections. Yet, its contribution to the field ofadvanced composites such as carbon fiber reinforced polymers is still limited by factors such as lowimaging contrast, due to scarce X-ray attenuation features.

Micro-computed Tomography (micro-CT) in Medicine and Engineering

A CT scan or computed tomography scan formerly known as a computed axial tomography or CAT scan is a medical imaging technique that uses computer-processed combinations of multiple X-ray measurements taken from different angles to produce tomographic cross-sectional images virtual "slices" of a body, allowing the user to see inside the body without cutting. The personnel that perform CT scans are called radiographers or radiologic technologists. Cormack and British electrical engineer Godfrey N. Hounsfield "for the development of computer assisted tomography. Initially, the images generated in CT scans were in the transverse axial anatomical plane , perpendicular to the long axis of the body. Modern scanners allow the scan data to be reformatted as images in other planes.

Она вспомнила об алгоритме Попрыгунчик. Один раз Грег Хейл уже разрушил планы АНБ. Что мешает ему сделать это еще. Но Танкадо… - размышляла .

UBC Theses and Dissertations

Сьюзан, не слушая его, повернулась к Соши. - Сколько там этих сироток? - спросила. Соши развела руками. Она села за терминал Джаббы и перепечатала все группы, а закончив, подбежала к Сьюзан. Все посмотрели на экран. PFEE SESN RETM MFHA IRWE ENET SHAS DCNS IIAA IEER OOIG MEEN NRMA BRNK FBLE LODI Улыбалась одна только Сьюзан. - Нечто знакомое, - сказала .

Она попробовала закричать, но голос ей не повиновался. Ей хотелось убежать, но сильные руки тянули ее. - Я люблю тебя, - шептал коммандер.  - Я любил тебя. У нее свело желудок. - Останься со .

Если Стратмор обошел фильтры вручную, данный факт будет отражен в распечатке.

the pdf pdf free download


Subscribe Now To Get Daily Updates