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Detection methods of energetic materials
Procházka, Michal ; Diviš, Pavel (referee) ; Friedl, Zdeněk (advisor)
A research on current methods of detection of explosives and related materials was made. At first the thesis studies methods of detection and analysis of explosives including chromatographic methods (TLC, GC, HPLC, IC), mass spectrometry and its variations, ion mobility spectrometry and infra-red spectroscopy. Next the attention is placed on detection of explosives in solid phase by X-ray detection, nuclear magnetic and quadrupole resonance and thermal neutron activation. Practical applications of these methods are of great importance in this thesis as well as their usage in the counterterrorist fight.
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THE INFLUENCE OF CONSOLIDATION PROCEDURE PARAMETERS ON COMPACTION OF AL POWDER
Lowe, T. C. ; Kunčická, L. ; Kocich, R. ; Davis, C. F. ; Hlaváč, L. ; Dvořák, Jiří
The influence of different consolidation procedures on compaction of Al powders was evaluated. Powder preparation procedures consisted of selection of particle size distribution, cold isostatic pressing (CIP), and vacuum sintering. Processing parameters investigated included the number of compression steps, compression pressure, and sintering temperature and time. Densities of the samples after compression and also after sintering were measured and compared. The overall oxygen content was analysed using by Energy Dispersive Spectroscopy. Phase composition was determined using X-ray. Microhardness measurements were performed to evaluate the degree of compaction. Double-step CIP at 200+300 MPa and subsequent sintering at 500°C for 60 min produced the best combination of properties from all the consolidation technologies of Al particles. Of the particle size ranges studies, those with diameters between 20 and 45 μm produced the best results. Aluminum oxide was present in the structure after all the processing treatments.
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Examination of the urogenital system Hospital Department of Radiology Jablonec nad Nisou p.o.
MENŠÍKOVÁ, Věra
The bachelor thesis named Examination of the urogenital system Radiodiagnostics Hospital Jablonec nad Nisou c. o. deals with methods of examination of the genitourinary system and creates a list and description of each method, using at these examinations. A radiology assistant is a non medical healthcare expert who uses their theoretical and practical knowledge gained during their university study in the fields of radiodiagnostics, radiotherapy and nuclear medicine. Radiology assistants are erroneously perceived both by other medical personnel and by lay public as technical workers. However, they are also medics who must be able to manipulate with highly sophisticated equipment but also provide medical care to the patients in full scale. As regards radiodiagnostics, the radiology assistants' task is to carry out the examination itself and obtain graphic documentation thereof. Radiology assistants ensure examination and handling of the equipment and they assist the doctor radiologist during more exacting intervention procedures. Radiology assistants' job is highly erudite and people working with ionising radiation must strictly abide by the laws and regulations stipulating strict rules and requirements which each radiology assistant must meet when they want to perform this activity. Radiology assistants' approach must help reduce the radiation burden of the population. It is logical, that the technological development goes hand in hand with higher examination yield and the ALARA principle is generally adhered to and applied in all examinations. If we strive to decrease the radiation dose, it is necessary to use an optimum amount of contrast agents. At the beginning of the thesis, there is a detailed description of urogenital system anatomy and physiology whose knowledge is a must when one wants to work in this field. Imaging methods described in the thesis range from the simplest ones to the most complex ones, both as regards the examination time and pursuant to specifications associated with individual examination types. The examination should be carried out from the least invasive examination procedures to the most complex ones. The methodics is based on gathering, study and subsequent analysis of the obtained data. Data from years 2009 2013 obtained at the radiodiagnostic ward of Nemocnice Jablonec nad Nisou p.o. hospital was gathered for this purpose. Investigations are divided into a number of men and women undergoing these tests. Investigative methods are compared, and evaluated that prevail, and from which they are abandoned prevail and which are being gradually abandoned. For the purpose of my thesi. The gathered data was processed into tables and synoptic graphs. Information from expert books, articles and verified Internet sources were used in the bachelor thesis. Results of my study confirmed the research question, the number of patients who undergo examinations of the urogenital system Radiodiagnostics Hospital Jablonec nad Nisou after rising. Preference tests are noninvasive and greater diagnostic yield. It is also found, however, that certain examination still have their place and are being replaced by another method. This example of hysterosalpingography. The aim of the thesis was to create an overview and description of individual radiodiagnostic methods in uropoetic system examinations and analysis of data from radio diagnostic department Hospital Jablonec nad Nisou regarding the examination of the urogenital system. The number of examinations in the radiodiagnostic ward is rising and the demands placed on a radiodiagnostic assistant are also continuously increasing from both physical and mental point of view. Radiology assistants are obliged to improve their knowledge and skills actively by means of training sessions and self study.
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Monitoring the effects of new exposure parameters after transition to CR digital image processing in the Radiodiagnostic Department at Sušice Hospital, o.p.s.
KLIMENT, Karel
At the current time, doses of radiation caused by medical exposure make up the largest part of peoples' exposure to artificial sources of ionising radiation (SIR). Every medical exposure must be justified as of benefit to the individual subject to it. Radiation protection at the workplace is subject to the principle of optimisation. One of the paths leading to optimisation of radiation protection is the specification of the Local Diagnostic Reference Level (LDRL). The objective of this thesis was to test and evaluate whether and how transition to indirect digitisation affects image quality. According to model examinations on a water phantom, the lowest possible dose for which image quality would be preserved was to be determined. If the dose could be reduced, it would be possible to specify a new LDRL. The dose can be reduced, amongst other things, by making appropriate adjustment to exposure parameters on the control unit. I tested how changes in the exposure parameters set affected the quality of the resulting image. I used the water phantom for each examination which corresponded to the thickness of the area to be examined for a standard patient. For constant default voltage, first of all changes to the settings were made to reduced blackening and increase electrical charge. Subsequently, voltage was increased and reduced with a constant blackening level. Image quality was evaluated according to the measured values for noise, and high and low contrast resolution. I used the results to determine recommendations for specific examinations in terms of exposure parameters to be set. I worked out the LDRL for the new exposure parameter settings and compared it to the current LDRL values at the workplace and with the NDRL (National Diagnostic Reference Level).
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Radiological visualization methods of the cranium by children
BALABÁNOVÁ, Klára
In this bachelor work were examined the imaging methods of the children´s skull. The number of the skull injury move upwards with the rising age. There are different causes of the skull injury falling on the head, car accident, but it could be also an effect of the abuse. It depends on the doctor, which of the examination methods he chooses. All patients and especially children must have the radiation load as small as you can get it. The chosen examination method must bring high-quality result. Special approach to children, professionalism, thoroughness and patience are in the pediatric radiology necessary, because the cooperation with the children is sometimes very difficult. Knowledge of clinic pediatrics and special knowledge by some examinations are required, because children´s disease have another development as by adults. The goal of this work is to acquaint with the radiological visualization methods of skull, as for example X-ray, computational tomography, magnetic resonance and sonography. Particular visualization machines and methods were described in the work. One separate chapter was dedicated to particular X-ray projections. Sonography is more and more used, mainly in the group of small children, for example to post-natal examination of hips. CT is also more and more indicated because of its speed. CT and MR are very difficult for children and their parents, but also for staff. The children could be afraid of the tunnel construction of this machine. Because of the difficult cooperation with the children it is sometimes necessary to give them calming stuff or general anesthesia. There must be an approval for the examination from the parents or legal representative, when these stuffs are given or when different examination machines are used. In the work is also described the anatomy of the skull, there are also described the differences between children´s and adult skull, development of the skull and the sexual differences of the skull. The form of the children´s skull is different from the adult skull. The goal of the second part is to compare the number of examination from the year 2008 to 2013 depending on imaging modalities (RTG, CT, MR), age and sex. The next goal is the gaining of the total number of examination of children´s skull divided into different examination modalities. The goal was to find an answer to a question, whether special X-ray images are still indicated, also when CT is available and whether the number of indications that serve to examination of children by magnetic resonance rises. To answer this research question it was used the statistics from the radiological department of Klinikum Passau and it was made the analysis. The chapter "Results" contains graphs that are made from the available statistics. The graphs are described in this chapter. Some of the results are represented in tables. This chapter is connected with another chapter "Discussion", where the results from Klinikum Passau are compared with the results from two bachelor works and two articles in the journal Injury Prevention, poisoning and violence. The results show the all goals of the work were fulfilled and represented and the answer on both research questions is positive. Yes, the special X-ray images of the skull are still indicated, also when CT is available and the number of indications that serve to examination of children by magnetic resonance still rises. Interesting result was that the most frequent examination in Klinikum Passau in the radiological department was in the last years the examination by magnetic resonance with the contrasting stuff. The statistics was influenced by the fact that it was worked out just in radiological department. Children´s department is separate and has its own X-ray, so there are also X-ray images. This bachelor work can serve as an educational and additional material for students and the workers of this profession.
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History of development of X-ray optics in Czech Republic
Inneman, A. ; Pína, L. ; Hudec, René ; Černá, D. ; Maršíková, V. ; Melich, Zbyněk
The summarizing paper sums up more than 40 years of research and development of grazing incidence X-ray optics in the Czech Republic. The origin of astronomical X-ray optics is related to spaceInterkosmos programme Interkosmos. Overall sixty pieces of Wolter I X-ray objectives were manufactured in key cooperation with the Optical Workshop of the Academy of Science in Turnov. Eight of them were used in four different space missions. After the end of Interkosmos project the development of X-ray optics was reoriented to X-ray laboratory tools for crystallography, to Lobster eye systems for wide-angle space monitoring and to Kirkpatrick-Baez imaging system for large X-ray space telescopes. At present, the novel concepts and technologies for X-ray space telescope considered in future ESA, NASA and JAXA missions are being developed
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X-RAY controlled implantation stents to stenoses in gastrointestinal system.
CERKUNÍKOVÁ, Anna
X-ray controlled stent implantation into gastrointestinal tract stenoses is a modern mini-invasive method. Many medicine branches have gone through considerable development in the second half of 20th century. In many cases it has been based on new discoveries in disease pathogenesis, new approaches in therapy and most importantly on new technical possibilities. This thesis describes treatment of stenotic tumors in gastrointestinal tract that used to belong to frequent surgery indication, regardless of possible radicality. Intervention radiology is a dynamic and quickly developing specialisation. New material and procedures development extends the possibilities of mini-invasive therapy in gastrointestinal tract illness. Instead of surgery, stent implantation is indicated in many cases. This method has many advantages when comparing with surgery, e.g. lower invasivity without general anesthesia usage and short recuperation. Indications of stent implantation into gastrointestinal tract stenoses can be divided according to more aspects, e.g. stenosis localisation, stenosis etiology, inborn or acquired stenoses and last but not least benign and malign stenoses that are the main topic of this thesis. The aim of this thesis is success and effectively assessment in stent implantation into gastrointestinal tract stenoses. The procedures are divided according to stenosis localisation in a certain period. The results are compared with other centers in the Czech Republic. In every procedure, we assess the etiology, stenosis localisation, patient age and sex, procedure type and its success rate, early and late complications (to 30 days from the procedure). As in the majority of cases we analysed patients with inoperable malign tumors, the mortality was not assessed. This thesis confirms the only chosen hypothesis ? the stent implantation in gastrointestinal tract stenosis is a quick and effective method with a low number of complications. Our department wants to use the data acquired in practise to compare the success rate and complication number with other centers and according to the results to confront the procedure method.
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Design and use of novel compression device for microtomography under applied load
Fíla, Tomáš ; Zlámal, Petr ; Koudelka_ml., Petr ; Jiroušek, Ondřej ; Doktor, Tomáš ; Kytýř, Daniel
This paper deals with modification and usage of custom-designed compression device, that allows real time X-ray tomography scanning of specimen under applied pressure. In this case microtomography is used to obtain data required to determine specimens morphology and to develop 3D material model (especially for cellular materials such as bones, metal foams and quasi-brittle materials or particle composites such as concrete or cementitious composites). Important design changes were made in the existing device frame to increase its load capabilities, stiffness and to accomodate a larger specimen. Finally device displacement measurements were conducted and calibration experiment was carried out.
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High resolution computed tomography - its role and position in radiodiagnostics
CHYLÍKOVÁ, Renáta
In the introduction to my bachelor´s thesis, I have described the historical background of HRCT, its origins, and evolution. The historical part includes information about the development of CT equipment and the principles of diagnostics using the instruments that preceded HRCT. In the following part, I have described the principle of how HRCT works and the conditions that are needed for HRCT examination. I focused on lung examination and partly also on the examination of temporal bone. The objective of my thesis is to determine the frequency of CT and HRCT application, for the purposes of which I compared two leasing hospitals in the South Bohemian region. I issued from the hypothesis of a higher frequency of HRCT use. In my bachelor´s work I used foreign literature and sources and also the method of comparing data from two hospitals. The preferred method was the quantitative one, used for numerical statistics in the theoretical part; for the practical part I used the mentioned comparison of the number of examinations performed at two hospitals in South Bohemia. When confronting the two hospitals, a significantly higher frequency of HRCT use was found in Nemocnice Tábor a.s. This fact is explained by the use of Aquilion 16, which is a lower ? quality appliance, and Aquilion 64 in České Budějovice, as well as by the monitoring of patients with fibrosing processes (so ? called cordarone lung, etc.), and patients with unclear small lesions appearing on summing images when only HRCT examination was performed. HRCT is also performed as a part of routine examination of the lungs and mediastinum if the indication requires it, while check ? up examinations run only under the HRCT algorithm. In conclusion it can be stated that the difference between the examinations in hospital České Budějovice a.s. and Nemocnice Tábor a.s. is based on the difference between their equipment and also the slightly different approach to small lesions in the pulmonary parenchyma.The hypothesis that the HRCT examination is used more frequently than the common CT examination of the lungs and mediastinum was not confirmed, which results from the fact that the number od patients needing the examination of just small or larger changes in the pulmonary parenchyma is substantially lower than the number of patients with indicated classical examination of the lungs and mediastinum.
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