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Simulated chemical accident associated with the release of phosgene
NOVÁK, Jan
The thesis entitled "Simulated Chemical Accident Associated with Phosgene Leak" focuses on the issue of disasters in general and specifically on chemical disasters associated with leakage of dangerous chemicals. The thesis consists of a theoretical and a practical part. The theoretical part of the thesis is divided into four subchapters. The first subchapter deals with accidents in general, and the classification thereof into natural and anthropogenic contingencies. The subject of the second chapter deals with specification of accidents that occur in the chemical industry. A special focus is given to causes of chemical accidents, among which there are anthropogenic (human factor) and technical causes as well as working conditions and organization of work. As regards classification, chemical accidents are divided into chemical accidents associated with leakage of dangerous chemicals, further accidents with leakage of radioactive substances and those involving oil leaks. With regard to the topic of the thesis, the third subchapter specifically focuses on characteristics of chemical accidents associated with leakage of dangerous chemicals. This is the key part of the theoretical basis of the thesis. The subchapter deals with causes, classification, development, characteristic effects and consequences of such accidents. Factors are also mentioned that affect the spread in the environment of dangerous chemicals leaked as the result of chemical accidents depending on a number of conditions. The fourth subchapter is linked to the preceding chapter in that it provides a brief characteristic of dangerous chemicals. A special focus is given to a comprehensive specification of phosgene. The core of the practical part of the thesis lies in the implementation of research consisting in simulation or modelling of a chemical accident associated with leakage of a selected chemical from a particular chemical plant. For the purpose of modelling phosgene was selected as the dangerous chemical. The company Synthesia, a. s. located in Pardubice, was chosen as the chemical plant in question. The practical part of the thesis aimed at modelling a chemical disaster associated with phosgene leak at Synthesia, a. s. The software tool TerEx, version 2.9.1. was used for simulation. Using this computer program a total of ten contingency scenarios were prepared involving phosgene leaks of different quantities as consequence of a chemical accident at Synthesia, a. s. Another aim of the practical part of the thesis was to assess risks following from the chemical accident. This assessment was made on the basis of the results of the TerEx program in the form of toxic exposure, recommended examination of toxic phosgene concentration within certain distance from the place of leakage, areas of necessary evacuation of the population, and last but not least time dependence of phosgene concentration and accumulated dose within distances of necessary evacuation of the population. The third and also the last aim of the practical part of the thesis was to assess impacts of this potential chemical accident on the health or lives of the population. The results of the modelled chemical accidents involving phosgene leak from Synthesia, a. s. showed that this contingency would especially impact health but not lives of the population. The phosgene concentrations showed only threshold levels (from 10 to 20 mg/m3) that would cause irritation of the eyes and the upper respiratory tract / nasopharynx. Even though the results of the research showed that no serious impacts on the health of the population should occur, the worst possible contingency scenario should always be considered in the event of such chemical accident.
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STM study of metal adatom mobility on Si(100) surface
Rozbořil, Filip ; Ošťádal, Ivan (advisor) ; Mysliveček, Josef (referee)
Surface diffusion of group III and IV metals on Si(100) is studied. Three methods for obtaining diffusion barriers are presented and discrepancies in published results are discussed. Room temperature growth of Al on Si(100) is studied using STM, observing a monomodal scaled island size distribution function. A Kinetic Monte Carlo simulation model is employed to obtain bonding energies and diffusion barriers for Al/Si(100). The best agreement between the measured and simulated characteristics is found for strongly anisotropic diffusion with barriers 0.60 eV in the direction orthogonal to the Si dimer rows and 0.80 eV in the parallel direction. Modifications of the cooling system required for observing metal adatom diffusion on Si(100) using STM are described and the first low-temperature experiment is carried out.
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Molecular simulations in structure analysis of intercalates
Veteška, Marek
The samples of hydrotalcite intercalated with pyrenetetrasulphonate acid were obtained. Their structure cannot be precisely determined by the analysis of X-ray data. The amount of water in the interlayer space and the structure of the samples differed considerably in dependence on humidity. Convenient procedures and minimization strategy were established on the base of X-ray data in the molecular mechanic and the molecular dynamic simulations. A procedure for using of the supramol software was made. This software enables deterministic searching of conformational space. Initial models from supramol were minimized in the Cerius2 software using the Universal force field and then they were eventually optimized by the molecular dynamics. The arrangement of molecules of pyrenetetrasulphonate acid and water was determined in the interlayer space of hydrotalcite for three different samples with different interlayer distances: The sample 1 prepared by RH = 0%: 9.83A; the sample 2 prepared by RH = 84%: 13.63A; the sample 3 prepared RH = 40%-50%: 11.74A a 12.81A. The results of these structures proved a large variability of the arrangement of the molecules in the interlayer space. The sample No. 3 seems to be unstable.
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Simulation of nesting of birds
Tóth, Peter ; Knap, Tomáš (referee) ; Brom, Cyril (advisor)
Theory (Storch and Frynta, 1999) suggest that in a process of the evolution some species acquire ability to select better habitats upon presence of habitat features which correlate with expected tness. As far as we know this theory was not yet tested with computational agent-based model. In this thesis we introduce computational agent-based model describing life cycle of autonomous agents in their habitat for studying evolution of habitat selection according to the theory. Results of the simulation show ability of the agents to adopt on differenct habitats by acquision of proper cognitive clues and formation of separate groups of agents within species.
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Supply Chain Management and its optimization
Alipčenkov, Timur ; Kuncová, Martina (advisor) ; Fiala, Petr (referee)
Dissertation work comes with a summary of logistics evolution in the sphere of Supply Chain Management and focuses readers attention on the processes inside of supply chain. However dissertaion work is not just a huge methodological part, it also comes with an optimization part. Reader meets imaginary company trying to optimize a part of its distribution process by using modification of distribution technology "Hub and Spoke". Optimization computational procedure also consist of Traveller Salesman Problem (TSP). Fictional data for three days of testing where prepared by using MS Excel function of random numbers. For longer testing period dissertation work uses simulation technology represented by SIMPROCESS software.
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Derivative Pricing Using Monte Carlo Simulations
Burešová, Jana ; Witzany, Jiří (advisor) ; Málek, Jiří (referee)
Pricing of more complex derivatives is very often based on Monte Carlo simulations. Estimates given by these simulations are derived from thousands of scenarions for the underlying asset price developement. These estimates can be more precise in case of higher number of scenarions or in case of modifications of a simulation mentioned in this master thesis. First part of the thesis includes theoretic description of variance reduction techniques, second part consists of implementation of all techniques in pricing a barrier option and of their comparison. We conclude the thesis by two statements. The former one says that usage of each technique is subject to simulation specifics, the latter one recommends to use MC simulations even in the case a closed-form formula was derived.
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Properties and in vitro Degradation of Metalic Biodegradable Materials
Ročňáková, Ivana ; Trojanová, Zuzanka (referee) ; Vojtěch,, Dalibor (referee) ; Podrábský, Tomáš (advisor)
Biodegradable metallic materials for medical applications have received considerable attention in recent years. The main reason is that they provide high potential for fabrication of temporal orthopedic implants such as bone fixation devices. Magnesium is an excellent candidate for fabrication of biodegradable implants due to its biocompatibility, mechanical properties similar to human bone and relevance for biological body functions. The fast degradation rate of magnesium and its biodegradable alloys in physiological environment limits its clinical application. Another attractive material in the field of biodegradable materials is zinc, which is among the essential elements in human body. Zinc exhibits an excellent corrosion resistance, and inferior biocompatibility compared to with magnesium. Hence, surface modification to form a hard, dense/porous, biocompatible and corrosion resistant modified layer has become an interesting topic in magnesium base biomaterials. Since hydroxyapatite is well tolerated by living organisms and in addition, improves the bone growth, it appears to be excellent candidate for such coatings on surface of biodegradable materials (e.g. Mg, Zn). This thesis is focused on comparison of corrosion behavior of pure non ferrous metals (Mg, Zn) and metals coated with hydroxyapatite, in simulated body fluids. The present approach is the use of modified atmospheric plasma spray technology to produce the hydroxyapatite coatings – suspension spraying. Composition and structure of the coatings and corrosion products were studied by light microscopy, scanning electron microscopy equipped with energy dispersive microanalyzer and X-ray diffraction. Corrosion of Mg and Zn samples was monitored by weight loss and determined by X ray and micro-tomography. The application of the HA coating resulted in decrease of corrosion rate of pure Mg. The corrosion rate of coated Mg samples was lower by 27,3 % in comparison with the corrosion rate of pure non coated Mg. Corrosion degradation of uncoated and coated Zn samples was minimal. The aplication of HA on the non ferrous surface appears to be a very promising method to improve corrosion and biological properties of these biodegradable materials.
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Buildings for education - energy and indoor environment
Čišecký, Ladislav ; Adam, Pavel (referee) ; Hirš, Jiří (advisor)
Diploma thesis deals with evaluation of indoor environment of a school complex in atypical Himalayan alpine environment which is totally dependent on energy originating from renewable sources. Structural design of buildings allows maximum utilization of solar energy which is the only one actually available source of energy in this area. The buildings are de-scribed in detail, as well as measurement conducted in buildings during the last year. The out-comes of measurements are compared with desired values. The thesis is also focused on math-ematical simulations by using BSim software. The output of a building energy simulations is an energy use prediction and design of appropriate measures to improve the current situation.
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Planar Structures for High Frequency Band
Pulec, Jiří ; Pietriková, Alena (referee) ; Maschke, Jan (referee) ; Szendiuch, Ivan (advisor)
The present paper deals with the problematics of the design and technology of planar microelectronic structures for the hign frequency band. These structures were realised on the Department of Microelectronics and their properties were measured on the Department of Radioelectronics. The part of this work is also simulation of some microelectronic structures, where for these simulations the design and simulation tool Ansoft Designer and the FEM tool ANSYS was used. The attention is paid to the discrete devices (coils and capacitors) as well as to the more complex structures (frequency filters). The paper yields the new findings in the field of the design and technology of the discrete components as well as of the more complex systems, these findings can be used as the basis for another research of practical applications.
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Adjusting Acoustic of Listening Room for Subjective Assessment of Quality of Audiovisual Systems
Bijota, Jan ; Kurc, David (referee) ; Schimmel, Jiří (advisor)
The thesis deals with acoustics of the listening room, which has to be modified to fulfil requirements in reccomendation ITU-R BS.1116. It analyses electro-acoustic reproduction chain, geometric and acoustic properties of the listening room and it also deals with conditions, which the reccomendation imposes on reference listening area. Thesis proposes a solution of listening arrangements and listening room model design according to reccomendation. This model design will be used for acoustic simulation program purposes. Resources of this thesis were speaker data sheet and my own measuring of reference monitor loudspeakers, reference listening room and reference sound field. Listening arangement was made in Microsoft Visio 2013 software. SketchUp Make software was used for model design of reference room. This model design was imported to EASE simulating software and then I started reference sound field simulation. Results of measurements and simulation don't fulfil requirements in reccomendation ITU-R BS.1116. Room can be modified by bass traps, but this modification will only reduce reverbation time. This thesis offers an insight of reproduction chain analysis and also may serve for future modification purposes of reference listening room.
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