|
ELECTRON BEAM REMELTING OF PLASMA SPRAYED ALUMINA COATINGS
Matějíček, Jiří ; Veverka, J. ; Čížek, J. ; Kouřil, J.
Plasma sprayed alumina coatings find numerous applications in various fields, where they enhance the properties of the base material. Examples include thermal barriers, wear resistance, electrical insulation, and diffusion and corrosion barriers. A typical structure of plasma sprayed coatings, containing a multitude of voids and imperfectly bonded interfaces, gives them unique properties - particularly low thermal conductivity, high strain tolerance, etc. However, for certain applications such as permeation barriers or wear resistance, these voids may be detrimental.\nThis paper reports on the first experiments with remelting of plasma sprayed alumina coatings by electron beam technology, with the purpose of densifying the coatings and thereby eliminating the voids. Throughout the study, several parameters of the e-beam device were varied - beam current, traverse velocity and number of passes. The treated coatings were observed by light and electron microscopy and the thickness, structure and surface morphology of the remelted layer were determined and correlated with the process parameters. Based on the first series of experiments, the e-beam settings leading to dense and smooth remelted layer of sufficient thickness were obtained. In this layer, a change of phase composition and a marked increase in hardness were observed.\n
|
| |
|
Sorption and Stabilization of Metals/Mettalloids by Innovative Synthesized Sorbent Amochar.
Ouředníček, P. ; Trakal, L. ; Komárek, M. ; Pohořelý, Michael
Remediation of contaminated soil which is based on stabilization and immobilization of potential\nhazardous substance by sorption materials has been studied intensively nowadays. Biochar – activated organic carbon belongs to this group of stabilizing agents which can adsorb wide range of contaminants, including metals/metalloids. Surface area of the biochars is quite large in general and functional groups (e.g. COO–) can form chelates or alkaline elements on the surface, which is represented by cation exchange capacity. Altogether with the high pH values (7.00 – 10.00), biochars are quite effective sorbents and can adsorb metals/metalloids from the solution (ground water), especially in acidic soils (in the environments affected by intensive mining activities). Sorption\neffectiveness can be increased (especially for As (V) or Cr (VI) sorption) by modification of biochar by various types of secondary oxides. Innovative sorbent AMOchar (AMO + biochar) has been synthesized currently. The product was prepared by adding of biochar to the reaction solution during amorphous manganese oxide (AMO) synthesis. The AMOchar was formed mainly by Mn-oxalates which had coated surface of the pristine biochar. AMOchar composite was able to remove significantly higher amounts of various metal(loid)s from the solution despite the rather high pH of the material. Sorption effectiveness was high not only in case of Pb (II) sorption (almost 99%), and Cd(II) (51.2%), but also a very high amount of As(V), 91.4%. Additionally, both AMOchar composite was able to reduce Mn leaching. This can avoid potential post-contamination caused by the dissolution of less stable Mn-oxalates as observed in the pure AMO.
Fulltext: content.csg -  PDF
Plný tet: SKMBT_22316111113040 - PDF
|
|
Plasma spraying from liquids: plasma liquid interaction and coating build up
Tesař, Tomáš ; Mušálek, Radek ; Medřický, Jan ; Lukáč, František
Plasma spraying from liquid feedstocks is a rapidly developing field of thermal spraying since the coatings prepared from liquids exhibit some unique features, such as high hardness, thermal shock resistance or low thermal and electric conductivity. The key factor influencing the final coating character and properties is the input material which may be in the form of a suspension or a solution. Parameters of the selected suspension (solids concentration, viscosity, surface tension, chemical composition, etc.) or solution (concentration, etc.) determine its interaction with the plasma jet which strongly influences the coating buildup. This proceeding introduces the problematics of the interaction between the liquid feedstock material with the plasma jet and presents the way of evaluation of the coating buildup.
|
|
The use of biographical anamnesis in care for clients with dementia in homes for the elderly in České Budějovice.
ČÁPOVÁ, Pavlína
Basic theoretical background: The number of people suffering from dementia is increasing, mainly due to falling birth rate and lengthening of life expectancy. The World Health Organization deals with the issue of caring for clients with dementia in a detailed report. A summary of this report was written by the Institute of Health Information and Statistics of the Czech Republic.In this summary, it is stated that in 2011 the number of clients treated in outpatient care in the Czech Republic climbed to number 14,932 (of which 67% were women) diagnosed with F00 (Alzheimer's disease) and with F01 - F03 (other dementia) to 17,955 (of which almost were women). In 2010, the estimated global number of patients with dementia was 35,6 million. Our society constantly considers a person with dementia to be an uncommunicative client, who is very difficult to be cared (Kopecká, 2012). That is why dementia touches not only the bio-psycho-social, but also the economic field (Wija, 2012). The basis of the psycho-biographical model of care is to change the perspective to the client and to see him or her as a personality with his or her own individual, regional or collective biographical history. With the help of the psycho-biographical model, the care becomes more tolerant, as this model is primarily focused on maintaining and supporting self-care skills and reflecting client's current skills, especially his or her mental ability (Procházková, 2011). For clients with dementia it is essential to find a way to their emotional life, which can be achieved by means of the information from the client´s biography. The knowledge of the client's story of life will also explain his or her needs and requests in care (Kopecká, 2012). The psycho-biographical model improves care for clients with dementia, particularly in the area of individual care and activation of clients. Aims of the thesis: As for the research part of this thesis, two objectives were defined. The first objective was to find out nurses' opinions about the use of biographical history in homes for seniors in České Budějovice. The second one was to discover the influence of biographical history in care for clients in homes for seniors in České Budějovice. These research questions were set to these objectives: What do nurses working in nursing homes for seniors in České Budějovice think of the influence of biographical history in care for clients? Another research question was: In what ways do the nurses working in nursing homes for seniors in České Budějovice think the biographical history improves care for clients? Methodology: The research on the topic of using biographical history in caring for clients with dementia in nursing homes for seniors in České Budějovice was conducted via qualitative investigation. Semi-structured interviews with nurses working in nursing homes for seniors in České Budějovice were chosen for the data collection. Results: The results of the research showed that all respondents found the use of biographical history beneficial in care for clients with dementia, especially in the area of improving individual care, cooperation with the client and his or her family members and obtaining information about the client. All respondents would like to start using biographical history in caring for clients with dementia, although some of them would find the introduction of the model into practice quite problematic. Conclusion: The results of this research could be used to change the approach to care for clients with dementia and to improve the quality of care. This thesis could serve to nurses in charge as a background material for the introduction to this issue and for considering the possibility of introducing biography history in caring for clients with dementia, as all interviewed respondents reported working with clients´ biographies to be beneficial in care for clients with dementia.
|
| |
| |
|
Natural houses in gardens
Formánková, Kristýna ; Kunt, Miroslav (advisor)
Thesis discusses natural houses which are supposed to be part of our lives in the future. These houses may be for someone and they might prefer smarter building with non-recyclable materials when choosing a new housing. But it is necessary to think about our future and sustainable development. We also need to tell ourselves what is really a priority for our planet. There comes a time when they will prefer building materials which can be used somehow after some time or be recycled. This is related to the design of the garden. It is designed to fulfil an ornamental, economic and social function. The garden is an integral part of each house, therefore it is important for each element used to be creating the garden as a linked harmonious whole. The study deals with the concept of a natural houses home in accordance with the maximum use of the garden.
|
|
Zalužanský Brook Restoration Project
Lašek, Jakub ; Kalibová, Jana (advisor)
This thesis contains restoration project of chosen section of Zalužansky brook in Ústecký kraj. Project is processed at the level of documentation for territorial management according to decree no. 499/2006, of buildings documentation. Theoretical part captures professional literature research dedicated to restorations, spatial planning and buildings documentation. Analytic segment closely defines and characterise location of interest at first, although major part consists of designed restoration measures following requirements for creating a building documentation by mentioned decree. Benefit from this thesis is it's possible usage as a background material for documentation created by authorised engineer for water management and landscape planning.
|
|
Design of Experiment for Non-Stationary Processes of Production
Jadrná, Monika ; Macák, Tomáš (advisor)
The doctoral thesis is concerned with the services sector and the area of mass production. Particularly, the optimization of the product portfolio of the travel agency and the optimization of production rounds of ammunition.
The theoretical part deals with the current overview of discussed topic. Further, the terminology and methods of the decision-making process are defined to support decision making. The theoretical basis of research focused on the choice of appropriate input variables in the area of services, and on the choice of a particular material option in the production area and appropriate equipment for the production. The theoretical part forms the basis for the practical part of the thesis.
For the doctoral thesis was chosen an enterprise operating in the defined sector. Product portfolio for the services sector is optimised using Fuzzy logic and Fuzzy sets so that the enterprise can maintain its competitiveness in todays highly ambitious market. Product portfolio for manufacture is optimised for achieving desired properties of the product.
The main aim of the thesis is to propose a new methodological approach for the management of selected business processes in their nonstationary time course. The aim of the practical implementation is to verify the functionality of the proposed methodological approach, both in the area of services and in the field of mass production.
|
guest ::
