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Polimeric nanoparticles stabilised by surfactants
Pánek, Jiří ; Štěpánek, Petr (advisor) ; Pleštil, Josef (referee) ; Sedlák, Marián (referee)
Polymeric nanoparticles stabilised by surfactants Doctoral Thesis Abstract Jiří Pánek Supervisor: RNDr. Petr Štěpánek, DrSc. PRAGUE 2010 CHARLES UNIVERSITY IN PRAGUE Faculty of Science Department of Physical and Macromolecular Chemistry INSTITUTE OF MACROMOLECULAR CHEMISTRY AS CR, v. v. i. Department of Supramolecular Polymer Systems Polymerní nanočástice stabilizované surfaktanty Souhrn disertační práce Jiří Pánek Školitel: RNDr. Petr Štěpánek, DrSc. PRAHA 2010 UNIVERZITA KARLOVA V PRAZE Přírodovědecká fakulta Katedra fyzikální a makromolekulární chemie ÚSTAV MAKROMOLEKULÁRNÍ CHEMIE AV ČR, v. v. i. Oddělení nadmolekulárních polymerních soustav 1 INTRODUCTION In the light of recent development, nanotechnology is the driving force of current research of new materials both in materials science and in biomedicinal applications. Nanomaterials can be constructed either by a top-down approach when the desired structure is produced in an already existing material or by a bottom-up approach when the required configuration is made by self-assembly of building blocks using various physicochemical interactions. Polymers and copolymers represent an ideal system for engineering of self-assembled nanomaterials since they offer a wide range of combinations of building materials that may serve for this purpose. The aims of...
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Czechoslovak-Cuban Cinematic Cooperation in the 1960s
Matušková, Magdaléna ; Opatrný, Josef (advisor) ; Štěpánek, Pavel (referee) ; Skřivan, Aleš (referee)
The study analyzes the largely understudied cinematic cooperation between Czechoslovakia and Cuba in the first decade following the Cuban Revolution. It is based mostly on archival documents from the former Central Directorship of Czechoslovak State Film, the ministry of education and culture and the ministry of foreign affairs. Several chapters also draw from oral history, data collected from series of interviews with Cuban technicians and artists who have worked in Cuban cinema since the 1960s as well as Czechoslovak experts who worked at the Cuban Institute of Cinematographic Arts and Industries in the 1960s. The Cuban Institute of Cinematographic Art and Industry (CICAI), founded in March 1959 shortly after the triumph of the Revolution, faced a shortage of human and material resources since its inception. The film industry, which had been mostly in the hands of the Americans before 1959, lost much personnel due to mass emigration. Later on, due to the American blockade and embargo, it also lost its most important provider of films, material and equipment. The majority of CICAI's technician and artists were just starting and were lacking in technical knowledge required to make films. Czechoslovak State Film (CSF) offered extensive help to Cuban cinema, especially in the area of developing the...
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Design of the Anchorage Length of FRP Reinforcement with the Influence of Extreme Temperature Loading Due to the Effects of Fire
Vašátko, David ; Zlámal, Martin ; Čairović, Đorđe ; Lagiň, Juraj ; Zlámalová, Pavlína ; Štěpánek, Petr
The extremely high temperatures from fire exposure have a negative impact on the behaviour of reinforced concrete structures regardless of the type of reinforcement used. The reduced mechanical properties of the materials need to be taken into account in the design of the structure, including anchorage length, to ensure that the reinforcement does not detach from the concrete. In the case of Fibre Reinforced Polymers (FRP) reinforcement, there are limited number of codes addressing the design issues in a fire situation. This article, based on experimental findings, proposes a procedure for determining anchorage length of FRP reinforcement under elevated temperatures.
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The Methodology for Testing the Bond Between FRP Reinforcement and Concrete Under the Influence of High Temperatures and Fire
Zlámalová, Pavlína ; Zlámal, Martin ; Čairović, Đorđe ; Lagiň, Juraj ; Vašátko, David ; Štěpánek, Petr
The determination and understanding of the bond strength between FRP reinforcement and concrete, which ensures the mutual interaction of these materials, are indispensable for the proper, safe, and reliable design of concrete structures with internal reinforcement. This characteristic also serves as a fundamental parameter for designing the anchorage length of the reinforcement.
While it is one of the fundamental characteristics, there is no domestic or international standards defining the procedure for testing and determining the influence of high temperatures and fire on the bond strength between FRP reinforcement and concrete.
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The Effect of Stiffening of Fully Composite Modular Footbridge on Horizontal Loads
Vašátko, David ; Girgle, František ; Kostiha, Vojtěch ; Štěpánek, Petr
In the design of the footbridge structure, horizontal loads, primarily from wind effects, cannot be overlooked. During the research of the fully composite modular footbridge, low horizontal stiffness was revealed, which was significantly affected by the connection points. Horizontal stiffness is mainly controlled by the joint plates at the module connections, and therefore, horizontal stiffening in the plane of the cross members was proposed. The stiffening adheres to the modular system and does not interfere with the assembly of the footbridge for the required span. The different stiffness of the footbridge in the horizontal plane without and with the use of horizontal bracing was experimentally verified.
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Design of Load Bearing Concrete Structure
Klodner, Jan ; Vácha, Jaroslav (referee) ; Štěpánek, Petr (advisor)
This thesis is focusing on general issues of floor concrete slabs, technology, implementation, subsoil models, calculation of internal forces and design approaches. Based on these data the thesis monitors the behaviour of floor slabs according to the various parameters. It also includes three versions of design of the real floor slab, made of steel fibre reinforced concrete, reinforced concrete and prestressed concrete. Economic comparison is also included. In addition it developes a design of the chalice base and reinforced concrete column of the supporting hall system, instead of the original usual base with steel column.
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Design of concrete structures with FRP reinforcement
Januš, Ondřej ; Girgle, František (referee) ; Štěpánek, Petr (advisor)
The diploma thesis presents design of construction with FRP reinforcement. Including design process of cross-section with FRP reinforcement exposed to bending moment and shear force at ultimate limite state according to given standards and guidelines. Long term physical and mechanical properties of FRPs are taking into account. There are also compared load capacities of cross-section exposed to combination of bending moment and axial force, which were designed according to mentioned standards. In another part of diploma thesis there is a design of construction (precast gatehouse) with FRP reinforcement and steel reinforcement with ordinary and lightweight concerete.
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Optimized design of reinforcement of concrete cross section
Hudyma, Nazar ; Laníková, Ivana (referee) ; Štěpánek, Petr (advisor)
The subject of this thesis is the optimization of design variables of reinforced concrete cross-section, especially its reinforcement. To solve this problem, it was first necessary to elaborate a search section that discusses various methods and approaches for solving the problem. The research part also includes processing and evaluation of tasks solved by other authors in available literature. For the optimization task, in the following parts both the general formulation and the detailed formulation of the partial parts of the concrete reinforcement structure optimization process are processed. As an example of optimization, a simple beam is chosen, which is subjected to bending moment and normal force one load case, where the example will be divided according to the formulation of both the function and the vector of unknown parameters (variables) defining the exact shape and properties of the reinforced concrete section. The examples will then be tested with regard to the speed of convergence and the degree of deviation between the best solutions found for each optimization algorithm used. At the end there will be a comparison and evaluation of the solution of the given task, as well as a summary of the whole bachelor thesis with reference to another possible direction in the optimization problems focused on reinforced concrete structures. In the appendices there will be a solution of selected examples.
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Design of structures with FRP reinforcement
Matušíková, Anna ; Vácha, Jaroslav (referee) ; Štěpánek, Petr (advisor)
This diploma thesis presents available FRP software for calculating load bearing capacity of the structures reinforced with FRP and compares them between each other. Furthermore theory and algorithm of my own software is presented here. Load bearing capacity of structures which are reinforced with non-metallic reinforcement and loaded by combination of normal force and bending moment can be solved by my programme. Effects of high temperatures on the concrete structures can be included in the calculation. In the second part of the thesis is calculated load-bearing capacity and deflection of the real beam reinforced with FRP reinforcement and load-bearing capacity of member with FRP reinforcement with effect of elevated temperature. This has been done using my software. Comparison of results from hand calculation and laboratory load-bearing testing is done at the end. This laboratory testing was accomplished by Institute of Concrete and Mansory Structures at our faculty.
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