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Terner, Mark Robert. "The production of low-cost α-sialons via carbothermal reduction-nitridation of slag-based mixtures." Monash University, School of Physics and Materials Engineering, 2003. http://arrow.monash.edu.au/hdl/1959.1/9577.
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Wang, Xidong. "Synthesis of AlON and MgAlON Ceramics and Their Chemical Corrosion Resistance." Doctoral thesis, KTH, Materials Science and Engineering, 2001. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3120.
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In view of the excellent mechanical, chemical and opticalproperties, AlON (Aluminum oxynitride) as well as MgAlON(Magnesium Aluminum oxynitride) have drawn the attention ofmaterials scientists in past decades. In this thesis,thermodynamic properties, synthesis and corrosion resistance tooxygen and slag of AlON and MgAlON ceramics have beeninvestigated.
Gibbs energy of AlON and MgAlON with different compositionsand temperatures were estimatedby using thermodynamicquasi-parabola rule. Phase stability diagrams of Al-O-N andMg-Al-O-N systems at different conditions have been calculated.On the basis of thermodynamic analysis, AlON and MgAlONceramics were synthesized by hot-press sintering andcharacterized by XRD, TEM and HREM analyses. An X-raydiffraction standard file of MgAlON is suggested and sent toJCPDS.
The density of AlON synthesized was 3.63g/cm3, about 97.8% of its theoretical density. Thedensity of MgAlON is 3.55 g/cm3. Fracture toughness of AlON and MgAlON is 3.96 and4.06 MPa.m1/2. Three-point bending strength of AlON and MgAlONare 248 and 268 MPa, respectively, at room temperature andkeeps very high until 1723K. However the strength drops 189 and202 MPa for AlON and MgAlON, respectively, at 1723K. Thefracture section of AlON and MgAlON were examined and found tobe a mixed fracture of intercrystalline and cleavage fracturefor AlON and a mixed intercrystalline and transcrystallinefracture for MgAlON.
Oxidation experiments of AlON and MgAlON and a comparison ofthe oxidation behavior of AlON, MgAlON, O'SiAlON-ZrO2and NB-ZCM have been carried out. Undernon-isothermal oxidation conditions, oxidation of AlON exhibitstwo steps with a "S"-shaped curve due to the phasetransformation of oxidation product. As temperature increases,the oxidation product, γ -Al2O3formed at lower temperatures will transform intoα-Al2O3. Due to the differences in the molar volumesbetween α-Al2O3and γ -Al2O3, cracks are likely to be formed in the productlayer promoting further oxidation. MgAlON, O'SiAlON-ZrO2and NB-ZCM show only one step with paraboliccurves.
Isothermal oxidation experiments of AlON, MgAlON,O'SiAlON-ZrO2and NB-ZCM have been carried out in thetemperature range of 1373-1773K. At lower temperatures, MgAlONshows the best resistance to oxidation. But at highertemperatures, such as 1773K, AlON shows the best resistance tooxidation. O'SiAlON-ZrO2shows very good oxidation resistance in the lowtemperature range up to 1673K. But, as the temperature goes upabove 1673K, there is liquid phase produced during theoxidation process. Gas bubbles are also formed in the productlayer causing the flaking-off of some parts of the productlayer. Therefore its oxidation rate increases greatly astemperature rises to 1673K. In the case of BN-ZCM ceramics, dueto the evaporation of B2O3, the oxidation resistance seems to be poorest. Thechemical reaction activation energies for the initial stage ofoxidation of AlON, MgAlON, O'SiAlON-ZrO2and BN-ZCM are 218, 330, 260 and 254 kJ/molerespectively. And the activation energies at the laterdiffusion controlling stages are 227, 573, 367 and 289 kJ/molefor AlON, MgAlON, O'SiAlON-ZrO2and BN-ZCM respectively.
The roughness of the oxidation sample surfaces has beenmeasured by Atomic Force Microscope. As the temperatureincreases, the degrees of roughness of AlON and MgAlON surfacesincrease slightly due to the growth of crystal grain. Theroughness degree of BN-ZCM increases greatly because of theevaporation of B2O3. However the roughness of O'SiAlON-ZrO2decreases as the temperature increases from 1473Kto 1673K. The main reason is that the liquid phase (glass)produced during the oxidation process at high temperatures suchas 1673K and 1773K. The roughness degree of MgAlON, AlON,O'SiAlON-ZrO2and BN-ZCM are 234, 174, 75 and 63 nm respectivelyat 1473K, and 297, 284, 52 and 406 nm respectively at1673K.
Experiments of corrosion of AlON by CaO-MgO-"FeO"-Al2O3-SiO2slags were conducted in the temperature range of1693-1753K under static conditions as well as under forcedconvection. XRD, SEM-EDS and TEM analyses on the corrodedsamples were carried out.
The results showed that the diffusion was therate-controlling step in the initial stage of the corrosion.Thereafter, the slag formation (the product layer dissolvinginto the liquid slag) became more and more important. Thisaspect was further confirmed by fractal dimension analysis ofthe interface. The overall activation energy for the corrosionprocess with slag No.1 was evaluated to be 1002 kJ. Adding"FeO" to the slag greatly enhanced the corrosion rate probablydue to the reaction of the sample with "FeO".
Key words:AlON, MgAlON, Thermodynamics, Synthesis,Oxidation, Slag corrosion
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Merriman, Kristine Roberta. "The context of organic residues in archaeological vessels of ceramic and Bronze." Thesis, University of Oxford, 2014. https://ora.ox.ac.uk/objects/uuid:40bef755-49f0-4c51-ad13-41bf7bec55df.
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Since the 1970s, the study of molecular organics preserved in archaeological ceramics, commonly referred to as organic residue analysis, has been used to infer vessel use and study dietary, economic, and ritual activities in the past. The purpose of this project is to analyse organic residues from a variety of ancient vessels and attempt to understand further the relationship between molecular organic preservation and vessel characteristics. It has been previously assumed that the absorption of these organics in the ceramic matrix is predominantly responsible for their preservation. The clarification of this or other preservative mechanisms and the further understanding of the relationships of vessels with their contents has a direct impact on the interpretation of organic residues and vessel use. The first section addresses the preservation of molecular organics in pottery vessels from Tel Kabri, Israel; Tel Megiddo, Israel; and Lefkandi, Greece. The one hundred and thirty-three samples from these three sites represent vessels used in domestic, burial, ritual, and elite contexts from the Early Bronze Age through the Iron Age Eastern Mediterranean. The focus of the study is the quantification of residue yields and identification of potential links with vessel properties and characteristics of the ceramic samples. Sequential extractions using two methods, conventional chloroform/methanol solvent extraction and direct FAME extraction/derivatisation, were applied to the sherds to test the absorption and adsorption of organics into ceramic materials. The majority of samples were tested non-destructively, enabling the comparison of residue yields to certain vessel properties and characteristics displayed in the same sherds. Where available, data concerning vessel form, sampling location on the vessel profile, thickness measurements were recorded, and XRF measurements were taken, with this in mind. The second section investigates the question of whether bronze and copper alloy vessels have the capability to preserve molecular organics within their corrosion products. Twenty-two samples of corrosion and associated material from five Early Roman bronze vessels found in cremation burials during the A2 Pepperhill to Cobham project in County Kent, United Kingdom were studied for organic material. These samples provide some of the first evidence that the residues of original content are preserved in copper alloy vessels either through entrapment in or reactions with copper corrosion.
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Naalisvaara, M. (Mikko). "Mechanical properties and drying shrinkage of fibre-reinforced alkali activated fly ash/slag binder s using ceramic waste aggregate." Bachelor's thesis, University of Oulu, 2018. http://urn.fi/URN:NBN:fi:oulu-201805221855.
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Ordinary Portland Cement (OPC), one of the most used construction materials, is a significant contributor to greenhouse gas emissions, such as carbon dioxide. The manufacturing process of OPC requires large amounts of energy and it consumes Earth’s natural resources at a high rate. New methods to replace OPC have been developed for a few decades now, and one of the promising method is a class of materials known as alkali-activated materials (AAM). AAM’s require less raw resources to manufacture, due to utilizing various industrial by-products, such as blast furnace slag and fly ash. One-part alkali-activated binders require only dry materials that can be mixed and water is being added to the binder as the last step. This makes them easy to handle and transport. In this thesis, experiments regarding the mechanical properties and drying shrinkage were conducted on a set of different samples, including different fly ash-slag mix compositions and fibre combinations. Crushed ceramic waste was used as an aggregate, because it is currently a form of waste with very little use. It was found that using 40% slag and 50% fly ash was a desirable mix composition, and so it acted as the reference for fibre-reinforced mix compositions. Polypropylene (PP), basalt (Ba) and polyvinyl alcohol fibres (PVA) were tested in different combinations, with the total amount of fibres in each specimen at 1.5% (total volume). Results showed that generally the addition of fibres increased the total flexural strength. Freeze-thaw test results showed that flexural strength loss was lower with fibre-reinforced samples, and compressive strength generally isn’t negatively affected. Hybrid fibre mixtures showed the most promising results in terms of reducing drying shrinkage ratePortlandsementti, eräs yleisimmistä rakennusmateriaaleista, on merkittävä kasvihuonekaasupäästöjen aiheuttaja. Portlandsementin valmistusprosessi käyttää paljon energiaa, ja se kuluttaa maapallon luonnonvaroja hälyttävällä tahdilla. Uusia materiaaleja, joilla Portlandsementti voitaisiin korvata, ollaan tutkittu ja kehitelty jo vuosikymmeniä, ja eräs lupaavista ehdokkaista on alkali-aktivoidut materiaalit. Näiden valmistaminen ei vaadi paljoa luonnonvaroja, sillä useita teollisuuden sivutuotteita voidaan hyödyntää lähes suoraan raaka-aineina, kuten masuunikuonaa ja lentotuhkaa. Lisäksi alkali-aktivaatioreaktio on huomattavasti Portlandsementin valmistuksessa tarvittavia kemiallisia reaktioita ympäristöystävällisempi. Yksi-osaiset alkali-aktivoidut sideaineet ovat kiinteässä muodossa veden lisäämiseen asti, joten niitä on helppoa ja turvallista käsitellä ja kuljettaa. Tässä työssä suoritettiin kokeita, joiden avulla mitattiin erään alkali-aktivoiduista sideaineista valmistetun betonin mekaanisia ominaisuuksia, sekä kuivumisen aiheuttamaa kutistumista. Kokeissa tutkittiin optimaalista lentotuhkan ja masuunikuonan välistä suhdetta, sekä kolmen erilaisen kuidun vaikutusta lisäaineena. Rakenneaineena käytettiin keraamista jätettä, eli posliinia, joka murskattiin haluttuun raekokoon leukamyllyllä. Jätteenä posliini on huono kierrätettävä, joten sille mahdollisten käyttötarkoituksien löytäminen on tärkeää. Tulosten perusteella betonin pohjaksi valittiin lentotuhka-masuunikuonasuhteeltaan 40/50 koostuva variantti. Polypropyleeni- (PP), basaltti- (Ba) ja polyvinyylialkoholikuituja (PVA) testattiin eri suhteissa niin, että niiden kokonaisosuus aineen tilavuudesta oli 1,5 %. Tulosten mukaan yleisesti kuitujen lisääminen lisäsi näytteiden taivutuslujuutta. Jäätymis-sulamissyklit heikensivät kuidullisia näytteitä enemmän kuin kuiduttomia taivutuslujuustestissä, mutta puristuslujuudessa vaikutusta ei juurikaan havaittu. Kuivumisen aiheuttama kutistuminen vaihteli eri kuituyhdistelmien välillä, mutta yleisesti ottaen kuituyhdistelmät yksittäisten kuitujen sijaan aiheuttivat vähiten kutistumista
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Krawiec, Piotr. "Nanostructured Porous High Surface Area Ceramics for Catalytic Applications." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2007. http://nbn-resolving.de/urn:nbn:de:swb:14-1170181622265-56905.
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In the present work new methods were developed for preparation of novel nanosized and nanostructured ceramic materials. Ordered mesoporous silica SBA-15 was found to be useful as a hard template for the nanocasting of silicon carbide and allowed the preparation of high temperature stable mesoporous silicon carbide ceramics. Chemical vapor infiltration of SBA-15 with dimethyldichlorosilane at elevated temperatures yields SiC/SBA-15 nanocomposites. The subsequent HF treatment of those composites resulted in silica removal and preparation of mesoporous silicon carbide with surface areas between 410 and 830 m2g-1 and high mesopore volume (up to 0.9 cm3g-1). The pore size (between 3 and 7nm in diameter) and surface area of mesoporous silicon carbide were controlled by adjusting the infiltration conditions (time, atmosphere). The mesoporous silicon carbide prepared via this method showed high structural thermal stability at 1300 oC, exceeding that of the SBA-15 template. However, the ordering on the mesoscopic scale was low. Nevertheless, highly ordered mesoporous silicon carbide materials were obtained via polymer melt infiltration in SBA-15. The low molecular weight polycarbosilane used as a preceramic precursor was converted at 1300 oC to silicon carbide inside the SBA-15, and after subsequent silica removal by HF, a highly ordered mesoporous material was obtained. Ordered mesoporous silicon carbide prepared by the methods reported here, may be an interesting material as a support due to its high temperature stability, chemical inertness, high thermal conductivity and semiconductor properties. In contrast to the nanocasting approach, based on the complete pore filling, also a new in-situ procedure for the preparation of finely dispersed metal and metal oxide particles inside ordered mesoporous silica was developed. A swelling agent (toluene) was used to deliver a hydrophobic platinum precursor into the surfactant micelles before addition of silica source. Such an in-situ method resulted in very high platinum incorporation (80-100%), not achieved for any other in-situ preparation procedures. Additionally, the presence of platinum allowed to decrease the template removal temperatures. Moreover, the method was also extended to other metal or metal oxide/ordered mesoporous silica systems. This may be especially interesting for the preparation of ordered mesoporous materials with low melting points, where typically the structure collapses during the high temperature calcinations process. The in-situ synthesized V2O5/MCM-41 materials were used to prepare VN/MCM-41 composites via nitridation in ammonia at 800oC. This method allowed to prepare highly dispersed, X-ray amorphous vanadium nitride species, with high activity in the propane dehydrogenation. Compared to nitridation of supported vanadium oxide prepared via the ex-situ procedure, in-situ synthesized materials showed similar catalytic activity, in spite of having significantly lower vanadium loading. As an alternative for the preparation of supported nitride materials, a novel preparation procedure of bulk not supported nanocrystalline vanadium nitride with high surface area was presented. Instead of pure oxide powder (which was typically used in the preparation of high surface area vanadium nitride catalysts), a macroporous amine intercalated V2O5 was used as the starting material. The obtained nitride consisted of small crystallites and had a surface area up to 198 m2g-1. Moreover, this foam-derived VN showed significantly improved activity as a catalyst in propane dehydrogenation. This novel preparation method could also be extended to other systems such as ternary VMoxNy nitrides.
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Krawiec, Piotr. "Nanostructured Porous High Surface Area Ceramics for Catalytic Applications." Doctoral thesis, Technische Universität Dresden, 2006. https://tud.qucosa.de/id/qucosa%3A24989.
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In the present work new methods were developed for preparation of novel nanosized and nanostructured ceramic materials. Ordered mesoporous silica SBA-15 was found to be useful as a hard template for the nanocasting of silicon carbide and allowed the preparation of high temperature stable mesoporous silicon carbide ceramics. Chemical vapor infiltration of SBA-15 with dimethyldichlorosilane at elevated temperatures yields SiC/SBA-15 nanocomposites. The subsequent HF treatment of those composites resulted in silica removal and preparation of mesoporous silicon carbide with surface areas between 410 and 830 m2g-1 and high mesopore volume (up to 0.9 cm3g-1). The pore size (between 3 and 7nm in diameter) and surface area of mesoporous silicon carbide were controlled by adjusting the infiltration conditions (time, atmosphere). The mesoporous silicon carbide prepared via this method showed high structural thermal stability at 1300 oC, exceeding that of the SBA-15 template. However, the ordering on the mesoscopic scale was low. Nevertheless, highly ordered mesoporous silicon carbide materials were obtained via polymer melt infiltration in SBA-15. The low molecular weight polycarbosilane used as a preceramic precursor was converted at 1300 oC to silicon carbide inside the SBA-15, and after subsequent silica removal by HF, a highly ordered mesoporous material was obtained. Ordered mesoporous silicon carbide prepared by the methods reported here, may be an interesting material as a support due to its high temperature stability, chemical inertness, high thermal conductivity and semiconductor properties. In contrast to the nanocasting approach, based on the complete pore filling, also a new in-situ procedure for the preparation of finely dispersed metal and metal oxide particles inside ordered mesoporous silica was developed. A swelling agent (toluene) was used to deliver a hydrophobic platinum precursor into the surfactant micelles before addition of silica source. Such an in-situ method resulted in very high platinum incorporation (80-100%), not achieved for any other in-situ preparation procedures. Additionally, the presence of platinum allowed to decrease the template removal temperatures. Moreover, the method was also extended to other metal or metal oxide/ordered mesoporous silica systems. This may be especially interesting for the preparation of ordered mesoporous materials with low melting points, where typically the structure collapses during the high temperature calcinations process. The in-situ synthesized V2O5/MCM-41 materials were used to prepare VN/MCM-41 composites via nitridation in ammonia at 800oC. This method allowed to prepare highly dispersed, X-ray amorphous vanadium nitride species, with high activity in the propane dehydrogenation. Compared to nitridation of supported vanadium oxide prepared via the ex-situ procedure, in-situ synthesized materials showed similar catalytic activity, in spite of having significantly lower vanadium loading. As an alternative for the preparation of supported nitride materials, a novel preparation procedure of bulk not supported nanocrystalline vanadium nitride with high surface area was presented. Instead of pure oxide powder (which was typically used in the preparation of high surface area vanadium nitride catalysts), a macroporous amine intercalated V2O5 was used as the starting material. The obtained nitride consisted of small crystallites and had a surface area up to 198 m2g-1. Moreover, this foam-derived VN showed significantly improved activity as a catalyst in propane dehydrogenation. This novel preparation method could also be extended to other systems such as ternary VMoxNy nitrides.
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Kautto, Per. "Influences of palladium ceramics on valuable metal losses to a PbO-SiO2-Sb2O3 based silver smelting slag." Thesis, Luleå tekniska universitet, Industriell miljö- och processteknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-81308.
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Silver and palladium can be found in the so called palladium-ceramics which comes from catalyst production. These valuable metals needs to be recovered from these wastes in order to further increase both the environmental and economic sustainability of our society. This material has also been suspected of causing some problems at Boliden’s smelter Rönnskär during the silver smelting. Unfortunately due to the nature of massive economics at work in precious metal production there has not been much published work around this subject. Therefore this works seeks to increase the understanding of how this waste affects the A-slag in the precious metal production at Rönnskär. This work takes a look at how certain fluxes and temperatures affects the slag and metal phases, as well as how increasing the addition of the palladium-ceramic affects the melt. It does so by making screening tests with a basic setup of slag from the process, silver granules and additions of coke and sodium carbonate at different temperatures. The results show that using a reducing environment by adding coke does increase the recovery of the precious metals. Increasing the temperature of the melt also shows an improvement in the recovery of the precious metals. Furthermore the basis to an alternative way of using this material, consisting of smelting it together with silver and fluxing materials has been suggested in this work in order to eliminate the possible problems it causes in the current process.Silver och palladium kan finnas i materialet som kallas katalysatormassa som kommer från framställningen av katalysatorer. Dessa värdefulla metaller måste återvinnas från detta avfall för att öka hållbarheten i vårt samhälle både miljömässigt och ekonomiskt. Materialet har också varit en möjlig orsak till problem vid silversmältningen på Bolidens smältverk, Rönnskär. Tyvärr på grund av den enorma ekonomin kring ädelmetaller och deras produktion har det inte publicerats många artiklar om detta ämne. Därför försöker detta arbete att öka förståelsen av hur detta avfall påverkar A-slaggen hos ädelmetallframställningen på Rönnskär. Detta arbete undersöker på hur olika flussmedel och temperaturer påverkar slaggen och metallfasen, samt hur en ökad mängd katalysatormassa påverkar smältan. Det görs genom att göra flera testsmältor med en bas med slagg från processen, silvergranuler samt tillsatser av koks eller natriumkarbonat vid olika temperaturer. Resultaten visar att användandet av en reducerande miljö genom tillsättningen av koks ökar återvinningen av ädelmetallerna. En ökad temperatur på smältan har också visat på en ökad återvinning. Utöver detta så har grunden till ett alternativt sätt att använda sig av materialet tagits fram. Detta alternativ består av att smälta materialet tillsammans med silver och flussmedel och har tagits fram för att undvika möjliga problem i befintlig process.
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Leme, Thariany Sanches. "Desenvolvimento de vitrocerâmico utilizando escória de fundição /." Presidente Prudente, 2019. http://hdl.handle.net/11449/191307.
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Orientador: Agda Eunice de Souza AlbasResumo: Neste trabalho, vidro e material vitrocerâmico foram obtidos a partir de uma composição baseada no diagrama ternário SiO2-Al2O3-CaO, utilizando escória de ferro fundido, provenientes de empresas de fundição, e, cal hidratada (comercial). A escória foi caracterizada através de: espectrometria de fluorescência de raios X (FRX), para determinar sua composição química; difratometria de raios X (DRX), para a identificação das fases cristalinas e análise térmica (TG), para evidenciar as reações térmicas associadas à desidratação e decomposição dos compostos presente no material. O vidro foi obtido através do processo de fusão/resfriamento (melt-quenching), fundido na temperatura de 1450°C. Foram caracterizados através de: calorimetria exploratória diferencial (DSC), para determinar as temperaturas de transição vítrea e de cristalização e difratometria de raios X (DRX), para identificar a sua estrutura amorfa. O estudo da cinética de cristalização do vidro foi realizado através de métodos cinéticos não isotérmicos baseados na descrição teórica formulada por Johnson-Mehl-Avrami (JMA). Estes métodos descrevem os processos de nucleação e cristalização utilizando dados provenientes da curva de DSC. O estudo cinético teve início com a obtenção do material vitrocerâmico tratado termicamente à 900ºC por 1,5h e identificação das fases cristalinas formadas, utilizando DRX. Considerando a formação de três fases cristalinas, os parâmetros cinéticos foram determinados a partir dos ajustes dos d... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: In this work, glass and glass-ceramic materials were obtained from a composition based on the ternary diagram SiO2-Al2O3-CaO using cast iron slag from foundry companies and hydrated lime (commercial). The slag was characterized by: X-ray fluorescence (XRF) to determine its chemical composition; X-ray diffractometry (XRD), to the crystalline phases identification and thermal analysis (TG), to show the thermal reactions associated with dehydration and decomposition of the compounds present in the material. The glass was obtained by melt quenching at 1450°C. They were characterized by differential scanning calorimetry (DSC) to determine glass transition and crystallization temperatures and X-ray diffraction (XRD) to identify their amorphous structure. The study of crystallization kinetics was performed by non-isothermal kinetic methods based on the theoretical description formulated by Johnson-Mehl-Avrami (JMA). These methods describe the nucleation and crystallization processes using data from the DSC data. The kinetic study began by obtaining heat-treated glass-ceramic material, at 900ºC for 1.5h, and identifying the crystalline phases formed using XRD. Considering three crystalline phases formation, the kinetic parameters were determined from the DSC data adjustments by the Kissinger, Augis-Bennett, and Matusita and Sakka methods. The best fit resulted in three crystallization peaks. The activation energy (Ea) of the crystallization process was obtained using the Kissinger an... (Complete abstract click electronic access below)
Mestre
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Bergström, Lena. "Macroalgae in the Baltic Sea : responses to low salinity and nutrient enrichment in Ceramium and Fucus." Doctoral thesis, Umeå University, Ecology and Environmental Science, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-441.
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The brackish Baltic Sea is a marginal environment for both marine and freshwater species. The rate of ecological differentiation is presumably high due to strong selection pressure from a gradient of decreasing salinity that has been present in its current state for only about 3 000 years. Even more recently, increased nutrient loading due to human activities has affected the growth rate of species, with potential effects on their competitive interactions and responses to other regulating factors. I have investigated the potential effects of low salinity and nutrient enrichment on the distributional ranges of two marine macroalgae with a wide distribution in the Baltic Sea, the red alga Ceramium tenuicorne (Kütz.) Wærn and the brown alga Fucus vesiculosus L.
A field study in the northern Baltic Sea indicated a strong relationship between the community structure of macroalgae and abiotic factors even on a small, local scale. The abiotic factors are potentially modulated by eutrophication, which may have a strong effect on the depth distribution and abundance of macroalgae. On a regional scale, laboratory experiments suggested that nutrient enrichment is unlikely to affect the distribution of Ceramium and Fucus along the salinity gradient. Growth in Ceramium from the Baltic Proper was enhanced by nitrate and phosphate, but the response did not override growth constraints due to low salinity. Ceramium from the Gulf of Bothnia had an inherently lower growth rate that was not positively affected by nitrate and phosphate increase. In Fucus vesiculosus, reproductive performance was impaired by nitrate and phosphate levels corresponding to ambient levels in eutrophicated areas of the Baltic Sea, when measured by their effect on zygote attachment, germination, and rhizoid development.
The wide distribution of Ceramium in the inner Baltic Sea is probably related to local adaptation, rather than a generalized tolerance of different salinity levels. Ecotypic differences were observed when comparing strains from the Baltic Proper (salinity 7 psu) and the Gulf of Bothnia (4 psu). A high rate of vegetative reproduction was evident, although sexual reproduction was occasionally observed in salinity 4. In Fucus vesiculosus, genetic and morphological analyses of sympatric and allopatric populations of the common, vesicular, morphotype and a dwarf morphotype, characteristic for the Gulf of Bothnia, showed that the dwarf morphotype represents a separate evolutionary lineage. Also, vegetative reproduction was observed in Fucus for the first time, as supported by genetic and experimental data.
The results show that the biota of the inner Baltic Sea may have unique adaptive and genetic properties, and that it is highly relevant to consider subspecies diversity in Baltic Sea management.
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Bergström, Lena. "Macroalgae in the Baltic sea : responses to low salinity and nutrient enrichment in Ceramium and Fucus /." Umeå : Univ, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-441.
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Alekseev, Kirill. "Hazardous bauxite residue, blast furnace slag, and foundry sand application as the main components for environmentally friendly red ceramics production." Universidade Tecnológica Federal do Paraná, 2017. http://repositorio.utfpr.edu.br/jspui/handle/1/2868.
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Nesta pesquisa foram utilizados resíduos da produção de alumínio e ferro. Resíduo de bauxita, que também é chamado de rejeitos de bauxita ou lama vermelha, e escória siderúrgica são os principais resíduos da indústria metalúrgica. Também foi utilizada areia de fundição, que é um resíduo do processo de fundição. Estes três componentes foram utilizados em conjunto para desenvolver material cerâmico de construção. A idéia principal era usar apenas resíduos industriais, sem materiais naturais tradicionais. Os residuos de vidro e as cinzas de madeira foram adicionados às composições para deminuir o ponto de fusão das amostras. Na pesquisa, 24 composições foram queimadas a 800-1225°C e suas propriedades foram estudadas. As características mecânicas das amostras foram analisadas através do teste de resistência à flexão, medindo-se a absorção de água, densidade e retração linear. As propriedades físico-quimicas foram estudadas por XRF, XRD, AAS, SEM, EDS, LAMMA, mapeamento, DTA e TGA. O principal motivo para os resultados elevados de resistência à flexão (19,78 MPa) das amostras foi identificado como o desenvolvimento de novas formações amorfas. Como resultado da pesquisa, algumas composições foram sugeridas para a produção específica de materiais de construção. Composições contendo lama vermelha (40- 100%), escória siderúrgica (0-50%), areia de fundição (0-50%), resíduo de vidro (0-20%) e cinzas de madeira (0-20%), atenderam normas e regulamentos brasileiros para materiais de construção, podem substituir materiais cerâmicos tradicionais, que envolvem a enorme exploração de recursos naturais.In the presented research were used residues of aluminum and iron production. Bauxite residue, which is also called bauxite tailings or red mud, and blast furnace slag are the key wastes of metallurgical industry. There was also used foundry sand, which is a residue of casting process. These three components were used together to develop ceramic construction material. The main idea was to use industrial wastes only, no traditional natural materials. The waste glass and wood ash were added to the compositions in order to decrease melting point of the samples. In the research 24 compositions were sintered at 800-1225°C and their properties were studied. Their mechanical characteristics were analyzed using flexural strength test, measuring water absorption, density, and linear shrinkage. Physicochemical properties were studied by XRF, XRD, AAS, SEM, EDS, LAMMA, mapping, DTA, and TGA. The main reason for high results of flexural strength (19.78 MPa) of the samples was identified as a development of new amorphous formations. As a result of research, some compositions were suggested for specific construction materials production. Compositions containing red mud (40-100%), blast furnace slag (0-50%), foundry sand (0-50%), waste glass (0-20%), and wood ash (0-20%), according to Brazilian Norms and regulations for construction materials, may substitute traditional ceramic materials, which involve enormous exploration of natural resources.
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Klang, Katharina [Verfasser]. "The energy dissipation of the sea urchin spine as biomimetic concept generator for cellular ceramics and load-bearing systems / Katharina Klang." Tübingen : Universitätsbibliothek Tübingen, 2020. http://d-nb.info/1219064521/34.
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Cardoso, Marília Duarte. "Reciclagem de escória de forno panela de aciaria elétrica em material cerâmico." Universidade do Vale do Rio dos Sinos, 2009. http://www.repositorio.jesuita.org.br/handle/UNISINOS/4607.
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A escória é um dos inúmeros resíduos gerados nos processos siderúrgicos de fabricação do aço e tem como composição básica óxidos metálicos e nãometálicos. Dependendo do processo de geração ela pode ser escória de altoforno (fusão redutora de minérios) ou de aciaria elétrica (produção do aço). A escória do forno panela de aciaria elétrica, utilizada nesta pesquisa, é gerada na etapa do refino secundário no forno panela, sendo este o processo de refino secundário mais utilizado no Brasil. Existem outros resíduos gerados na aciaria como: pó de aciaria, refratários e plásticos, que às vezes por serem em pouca quantidade ou por questões operacionais da empresa não são segregados. A reciclagem de resíduos é uma prática que deve ser incorporada como uma alternativa quando não existe chance de minimização. Nos últimos anos as pesquisas sobre reciclagem externa das escórias voltaram-se principalmente para a incorporação em cimento e concreto (como agregado graúdo ou miúdofunção filler) e mais recentemente no material cerâmico, com poucos estudos ainda com escória do forno panela. Nota-se também que existe uma tendência mundial nas últimas décadas de reciclagem de resíduos em associação (mais de um resíduo na formação de um material) e normalmente isto ocorre em materiais cerâmicos devido a sua alta capacidade de incorporação de outros materiais. Esta pesquisa buscou com diversos métodos de caracterização da escória do forno panela de aciaria elétrica avaliar a viabilidade técnica da reciclagem em material cerâmico. Para as condições desta pesquisa e mediante ensaios (perda ao fogo, análise térmica, retração linear, resistência mecânica na flexão, absorção de água, porosidade aparente, análise visual e em lupa e MEV) com a escória do forno panela de aciaria elétrica, exceto no ensaio de absorção de água (corpos de prova sinterizados a 950°C - D1 com 5% e D45 com 10%), a escória mostrou potencial para ser utilizada como coproduto. Os corpos de prova D45 mostraram uma tendência de maior resistência mecânica que os corpos D1, isto provavelmente está relacionado a menor quantidade de CaO que a escória D45 contém, característica esta ligada ao seu maior tempo de estocagem. Os resultados obtidos permitem incorporar até 15% (teor máximo testado) da escória de forno panela de aciaria elétrica no material cerâmico com função de vedação ou estrutural.
The slag is one of the many solid wastes generated in the steelmaking processes of steel production, which is constituted by metallic and non-metallic oxides. Depending on the process of slag generation, it can be slag blast furnace (smelting reduction of ores) or electric arc furnace (steel production). The slag ladle furnace from electric steelmaking, used in this study is generated in the stage of secondary refining in ladle furnace, which is the stage of refinement most used in Brazil. There are other solid wastes generated in the steel plant, such as electric arc furnace dust, refractory and plastics, which are sometimes in small quantities, and because of operational issues the company is unable to be segregated. The recycling of solid waste is a practice that should be incorporated as an alternative when there is no chance of minimizing. In recent years research on recycling of slag outside turned mainly to the incorporation in cement and concrete (as aggregate or filler kid-function) and more recently a few studies are related to its addition in the ceramic material. Actually, there is a worldwide trend to recycle solid waste in combination (more than one residue in the formation of a material) and very often this occurs in ceramic materials due to its high capacity to incorporate other materials. This research, with the various methods of characterization of the slag from ladle furnace, were carried out to evaluate the technical feasibility of recycling in ceramic material. Considering the conditions of this study and all tests (loss on ignition, thermal analysis, linear shrinkage, mechanical strength in bending, water absorption, porosity, visual analysis and microscope and SEM) used to study the ladle furnace slag, except the test of water absorption (specimens sintered at 950°C - D1 to D45 and 5% to 10%), the s lag has shown a potential to be used as by-product. The samples D45 showed a trend of greater strength than the bodies D1, this is probably related to the least amount of CaO to the slag contain D45, a characteristic linked to its longer storage. The results show the incorporation up to 15% (maximum level tested) of the ladle furnace from electric steelmaking in the ceramic material as bricks or structural blocks.
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Krantz-Frid, Madelene. "Ecotoxicological effects from three antifouling paints on the red macroalga Ceramium tenuicorne." Thesis, Södertörns högskola, Institutionen för livsvetenskaper, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:sh:diva-3070.
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Antifouling paints are applied on vessels to prevent growth of fouling organisms such hasbarnacles. Presently, there are a number of different paints available on the Swedish marketwith different strategies and active substances. The paints might work by either continuouslyreleasing biocides or physically by peeling off or provide an easily cleansed surface whereorganisms cannot attach. The physically working paints do not need to register an activesubstance since its purpose is not to affect living organisms by a chemical or biological modeof action. In this study, two commercially available paints, the copper-based Fabi 3959(International Paint Ltd) and physically eroding, biocide-free labelled Mille Light (HempelFärg AB) were compared to Hard Racing superior, containing copper and the forbiddensubstance Tributyltin. Fabi International is only allowed to be used on the Swedish west coastdue to 6% added as active substance while the biocide-free Mille Light is eligible for eastcoast usage. The toxic effect from respective paint was investigated by assembling a growthinhibition test with the red macro alga Ceramium tenuicorne. The results show that all thestudied paints had a negative effect on growth and therefore leaked substances inconcentrations high enough to be harmful to the alga. The toxic response differed with theeffect on growth being in the following order, Hard racing superior>Fabi >Mille Light.Implications regarding the current legalization involving biocide-free labelled antifoulingpaints are discussed.
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Lindqvist, Dennis. "Hydroxylated polybrominated diphenyl ethers in Baltic Sea biota : Natural production, food web distribution and biotransformation." Doctoral thesis, Stockholms universitet, Institutionen för miljövetenskap och analytisk kemi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-135789.
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Hydroxylated polybrominated diphenyl ethers (OH-PBDEs) are naturally produced in aquatic ecosystems e.g. by algae. Many OH-PBDEs have been observed to be highly bioactive and to cause adverse effects through several pathways, e.g. via disrupting oxidative phosphorylation (OXPHOS). The levels of some OH-PBDEs have increased in Baltic biota over the past decades. This may be associated with the nutrient enrichment of the Baltic Sea, which has favored growth of some of the OH-PBDE producers. Ceramium tenuicorne has been suggested to be a producer of OH-PBDEs in the Baltic Sea, which is supported by the results presented in this thesis. The levels of OH-PBDEs were observed to fluctuate greatly in C. tenuicorne over the summer season, and to correlate with the levels of pigments in the algae. However, the observed congener pattern in C. tenuicorne questioned theories regarding the mechanism of their biosynthesis. The results indicate a much more selective pathway for biosynthesis than previously suggested for the production of OH-PBDEs. One of the most abundant OH-PBDEs in C. tenuicorne, 6-OH-BDE137, has previously been observed to be toxic to bacteria, fungi, and crustaceans. Furthermore, Baltic gammarids seemed to change their feeding preferences towards less grazing on C. tenuicorne during the production peek of OH-PBDEs in the alga. This suggests that OH-PBDEs may serve as allelochemical defense agents for C. tenuicorne. The transport and fate of OH-PBDEs through a Baltic food chain was also studied, including C. tenuicorne, Gammarus spp., three-spined stickleback (Gasterosteus aculeatus), and perch (Perca fluviatilis). A small portion of the OH-PBDEs were observed to be methylated in the alga, or by associated bacteria. The methylated OH-PBDEs biomagnified in the food chain up to perch, in which they were converted back to the OH-PBDEs via demethylation. The OH-PBDEs and their methylated counterparts were also partially debrominated in the food chain, which resulted in high concentration of 6-OH-BDE47 in the perch. This congener is the most toxic OH-PBDE with regards to OXPHOS disruption. Another biotransformation of OH-PBDEs was identified in Baltic Sea blue mussels (Mytilus edulis). High concentrations of OH-PBDEs were conjugated with lipophilic moieties, e.g. fatty acids. This increases the residence time of the OH-PBDEs in the mussels. Mussels have been suggested to conjugate steroids with fatty acids as a means to regulate hormone levels. The conjugation of OH-PBDEs to fatty acids may occur due to intrusion into this pathway. Methods were developed to include quantification of conjugated OH-PBDEs in the analysis of mussels. OH-PBDEs were also quantified in blood from Baltic Sea grey seals (Halichoerus grypus). Seals originating from the Baltic proper were observed to be more highly exposed to 6-OH-BDE47 than seals from the Gulf of Bothnia. However, the levels of OH-PBDEs were generally low. A major effort was invested into securing these results, including development of a new analytical method. Blood obtained from dead seals is a difficult matrix for quantification of OH-PBDEs, and previous attempts using an established method yielded unsatisfactory results.At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 4: Manuscript.
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Frade, Sander Bicalho. "Estudo de massas refratárias de vibração a seco para indutores de fornos de indução." Universidade do Estado de Santa Catarina, 2015. http://tede.udesc.br/handle/handle/1679.
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Vibration refractory masses are dry granulated materials obtained by combination of several refractory oxides, such as: silica, alumina, magnesia; magnesia-chromite and chrome-alumina. These materials are usually applied by dry vibration process and / or accommodation using special forks. In the process of performance evaluation of dry vibration masses there is a need for proper compaction of the material so that the technological characteristics are retained after sintering and firing, and that the specimens prepared in the laboratory have similar characteristics to those found in practice. With the objective of developing a methodology to study in laboratory of the behavior of refractories for induction furnaces, two magnesia and alumina refractories were selected, with the formation of spinels. These materials were compacted considering as varying the type and amount of additive and the number of impacts on manual compression. The results allowed the construction of densification curves to determine the processing conditions that maximized the densification. Specimens obtained by this process were thermally treated for evaluating of the mechanical strength after curing. The results showed that this developed methodology allows the development of appropriate specimens for the development of studies of dimensional variation and resistance to slag attack.
Massas refratárias de vibração são materiais granulados secos obtidos através da combinação de diversos óxidos refratários, tais como: sílica, alumina, magnésia; magnésia-cromita e alumina-cromo. Esses materiais são normalmente aplicados pelo processo de vibração a seco e/ou por acomodação utilizando garfos especiais. No processo de avaliação do desempenho de massas de vibração a seco existe a necessidade de um adensamento adequado do material para que as propriedades tecnológicas sejam mantidas após a sinterização e queima, e que os corpos de prova preparados em laboratório tenham características semelhantes às encontradas na prática. Com o objetivo de desenvolver uma metodologia para estudo em laboratório do comportamento de refratários para fornos de indução foram selecionados dois refratários de magnésia e alumina, com formação de espinélios. Estes materiais foram adensados considerando como variáveis o tipo e quantidade de aditivo e número de impactos na compactação manual. Os resultados permitiram a construção de curvas de adensamento para determinar as condições de processamento que maximizaram a densificação. Corpos de prova obtidos por este processo foram tratados termicamente para avaliação da resistência mecânica após cura. Os resultados mostraram que a metodologia desenvolvida permite a elaboração de corpos de prova adequados para o desenvolvimento de estudos de variação dimensional e resistência de ataque por escória.
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Ginalis, Alkiviadis. "Byzantine ports : Central Greece as a link between the Mediterranean and the Black Sea." Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:06056474-143b-4547-b7eb-3bf635994295.
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This thesis presents a first archaeological introduction to the study of Byzantine ports, harbours and other coastal installations in the region of Thessaly. Thessaly not only constitutes an ideal region to gain equal information for the Early- to the Late Byzantine periods, but also to compare independent regional and imperial central building activities. However, in particular Thessaly’s maritime connectivity has never been studied in detail before. As such, a first step into a terra incognita, the thesis is divided into two main sections: In order to conceptualize the study of harbour sites, the thesis first sets up a framework for the definition, understanding and interpretation of the physical features of harbours and their function and purpose. Taking into account influencing environmental conditions, such as natural, economic, social and political components, this helps to determine an accurate hierarchical model and to illustrate the interrelationship between different types and forms of harbour sites. Subsequently, comprehensive archaeological investigations around the island of Skiathos and other harbour sites in Thessaly, executed in 2012 and 2013, are set against this theoretical groundwork. In contrast to the common approach of regional studies, where a first general overview is followed by individual detailed case-studies, the opposite methodology is undertaken in order to achieve a systematic study of the Thessalian harbours and the complexity of their network system. Consequently, the collection of data starts from the analysis of a distinct area of a region and continues with the broader regional picture of primary ports, secondary harbours and staple markets. Functioning as an important junction of the Aegean shipping lanes and being involved in regional as well as supra-regional trade and port networks, focus is therefore primarily dedicated to the island of Skiathos. A joint survey project in cooperation with the Greek Ephorate for Underwater Antiquities (EEA), the 13th Greek Ephorate for Prehistoric and Classical Antiquities and the 7th Greek Ephorate for Byzantine Antiquities was initiated by the author in 2012. A number of sites, including harbour installations and other coastal infrastructures, have been detected, documented and subsequently verified by geophysical prospections, using a Sub-bottom profiler and Side-Scan Sonar, in 2013. These have allowed to draw a clear historical picture of architectural developments, port networks and changes in the socio-economic connectivity of the area. Followed by a close investigation of further harbour sites throughout the entire region of Thessaly during two field seasons between 2012 and 2013, the detailed picture gained from the Skiathos survey project is brought to a wider context. This comparison finally allows an overall picture of the history and architectural developments of harbour structures and associated coastal sites, as well as general conclusions concerning the hierarchy and port network in the region during the Early to Late Byzantine periods. This has allowed a comprehensive understanding of the growth, use and decline of various ports, harbours and staple markets within Thessaly and has important repercussions for our understanding of wider social and economic changes that were occurring during these periods, such as the rise of the church as a powerful economic institution or the increasing activities of private entrepreneurs. In this way the submerged maritime heritage of Thessaly has provided a rich new resource with which to understand the cultural dynamics of the region as it emerged from its peripheral location to comprising major ports within the Roman maritime network and to stand out of the heart of the commercial route ways to and from Constantinople, as well as being part of the emergent networks of the western maritime states at the end of the period, such as Venice.
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Olsson, Eriksson Linus. "Den svenska vallanläggningens ursprung: Låt brons och keramik leda vår väg." Thesis, Uppsala universitet, Arkeologi, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-353135.
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The function and symbolism of the Swedish bronze age rampart enclosures has been debated since the late 1800´s. Arguments highlighting their function as fortifications and/ or as ritual centres has been passed back and forth in what today seems to be a subject in a standstill. Very little has been done in comparing the Swedish enclosures with their European equivalents when it comes to the understanding of function. In the early 1990´s their origin in the Lausitz culture of the Late Bronze Age was put forth by several archaeologists, but one needs to keep in mind that this was a time where the Lausitz culture was an increasingly popular subject for Swedish archaeologists to study. In time the similarities between the materials came to be questioned from both an architectural and a chronological standpoint. This paper has therefore been focused on re-examining the Swedish rampart enclosures relation to the European hill forts and fortified settlements. By examining its relations to the import of bronze and ceramics between the southern and eastern coastal areas of the Baltic Sea area and Scandinavia around 1300-1000 BC, my main goal was to provide an updated and valid theory for the origins of the earliest Swedish rampart enclosures from the same time. Based on the analysis presented in this paper I have, to some extent, been able to distance the earliest Swedish rampart enclosures from the previous Lausitz origin theory. The conclusion is instead that an origin is to be sought in the earlier Únětice culture and it´s rampart fortified settlements from between 1800-1500 BC.
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Glasová, Veronika. "Penzion s wellness." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2020. http://www.nusl.cz/ntk/nusl-409996.
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The subject of my diploma thesis is the design of the pension with the possibility of wellness activities, which is located in the village of Holásky, on the level of documentation for the construction. The new building is located in the cadastral area Holásky. It is a three-storey, basement building in the shape of two bounce rectangles with separate parking for visitors to the pension and wellness. The supporting system consists of a reinforced concrete skeletal column system with a ceiling structure made of Spiroll core panels. Porotherm ceramic blocks with contact insulated facade according to ETICS are used for filling masonry. The roof structure is a single-skin flat roof.
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Nováková, Tereza. "Domov pro seniory v Trutnově." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2013. http://www.nusl.cz/ntk/nusl-226375.
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Subject of the diploma thesis is home for the seniors in Trutnov. The building is designed in steep terrain. The main entrance is oriented to the north. Consists of one basement and three storeys (floors). The house is built of building system Porotherm. Basement walls are concreet block. Ceiling construction consists of ceiling tiles Spiroll and Filigran. Roof construction is a flat. House is designed for disabled persons.
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Pospíšil, David. "Administrativní budova." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2013. http://www.nusl.cz/ntk/nusl-225855.
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My thesis solveses the office building. The building will be located in Šumperk. It will be located near the center. The building has two floors and a partial basement floor. Ceilings are beams with ceramic inserts and reinforced concrete slabs. Vertical structure consists of a ceramic blocks in the aboveground parts and concrete blocks in the underground section. The roof is walked on vegetation. The staircase is reinforced concrete, monolithic. The entire building is insulated with mineral wool. Basement is insulated with polystyrene foam.
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Dieulefet, Gaëlle. "Les voies détournées du commerce en Méditerranée : constantes portuaires et commerce interlope de la mer des Baléares à la mer Tyrrhénienne (XVe-XVIIIe siècles). : Nouveaux apports céramologiques." Thesis, Aix-Marseille, 2013. http://www.theses.fr/2013AIXM3062.
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Cette recherche doctorale s'intéresse à la culture matérielle maritime et plus particulièrement à un mobilier de bord, à usage individuel et collectif, dont les modalités d’acquisition restent très généralement marginales. Pour cela, la céramique, produite entre le XVe et le XVIIIe siècle provenant de dépotoir portuaire et d'épave répartis majoritairement sur le littoral nord-méditerranéen français, constitue notre support d’analyse. Considérée comme un artéfact majeur des contextes archéologiques, la céramique permet d'appréhender les échanges maritimes, la composition du vaisselier et une part de l'instrumentum de bord. L'approche diachronique de cette recherche donne lieu à une cartographie exhaustive de la répartition des épaves et des dépotoirs portuaires nord-méditerranéens afin de caractériser les aires de diffusion des céramiques rencontrées. Ces dernières, une fois analysées d’après une méthodologie adaptée aux problématiques de la recherche et confrontée aux sources écrites, nous fournissent de précieuses informations sur les relations et les usages en Méditerranée occidentale, selon les séquences chronologiques considérées et permettent de porter un autre regard sur des instants du quotidien des gens de merOur doctoral research deals with maritime material culture and especially in onboard furniture, used in a personal and collective way, whose modalities of acquisitions are usually marginal. Our analysis support is composed of ceramics produced between the XVth and the XVIIIth century coming from harbour dumpsite and shipwreck generally located on the north mediterranean French coast. Think as one major archaeological artéfact, ceramic may help to understand maritime exchanges, dishes and one part of the onboard instrumentum. The diachronic approach of this research leads to a repartition map of harbour dumpsite and shipwreck in north Mediterranean French coast. Our study shed light on the areas of ceramics distribution. We analyzed ceramics according to an adapted issue methodology and confronted with written sources. The results gives us valuable information on relations and uses in western Mediterranean, according to the sample chronology considered and allow us to better understand the everyday life seafarers
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Váňa, Jan. "Hotel s posilovnou." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2019. http://www.nusl.cz/ntk/nusl-396161.
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The subject of the diploma thesis is new stand-alone hotel with a catering service and a relaxation zone including a fitness room, a table tennis room, massages and a solarium. The individual functional parts are separated and can be operated independently of each other. The Building consists of three floors. The ground floor will serve to run a restaurant with a background and a for relaxation zone, the remaining two floors will be used to accommodate guests and the necessary facilities. The maximum capacity for the accommodation is 59 people and requires four employees to operate it. The restaurant is designed for 81 guests and a total of 7 employees. The relaxation part is for guests only and is not accessible to other people. The structure is based on strip foundations from plain concrete and reinforced concrete foundation footing. Peripheral vertical load-bearing structures of the first above-ground floor are designed from permanent formwork system, all others loadbearing walls will be walled-up from vertically perforated block laid on thin-film adhesive. The floor structures are designed as an assembly of prestressed hollow core slabs. Roofing of the building will be made as a flat vegetation roof.
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Jirka, Petr. "Penzion na cyklostezce." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2015. http://www.nusl.cz/ntk/nusl-227832.
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The subject of this thesis is a design of a newly built guesthouse on a bicycle path in the village Spálené Poříčí. The building is designed in a gently sloping terrain towards the west. The main entrance faces the south. It is an object without a basement and with two above ground floors. The structure of the building is a transverse wall system made of ceramic fittings. Other walls are also made of ceramic fittings. The entire building is based upon the stripe foundations and footings. Pension is covered in the part of the accommodation and in the restaurant part with a gable roof. For the restaurant, a terrace is designed on the west side of the building. In this thesis, static and building equipments are solved. The building is also evaluated in the terms of lighting, thermal, acoustic requirements and the fire safety of building is also solved.
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Kopečková, Kristýna. "Horský penzion s wellness." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2017. http://www.nusl.cz/ntk/nusl-265232.
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The subject of my thesis is the design mountain guesthouse with a wellness centre, which is located in the village of Mala Morávka, at the level of documentation for construction. The new building is located in the cadastre unit Karlov pod Pradědem. This is a two floors, slab-building L-shaped with separate parking for visitors of boarding house and wellness centre. The structural system is composed of ceramic blocks Porotherm and reinforced concrete joist floor. Roof structure is made up of wooden trusses girders saddle shape. Design of mountain guesthouse with wellness centre respects the territorial plan of the village of Malá Morávka.
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Ondráček, Michal. "Vývoj vysokopevnostních betonů definovaných vlastností s využitím druhotných surovin." Doctoral thesis, Vysoké učení technické v Brně. Fakulta stavební, 2013. http://www.nusl.cz/ntk/nusl-233787.
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Civil engineering development is connected with the application of new construction methods and the development of new building materials. Concrete, as one of the basic building materials, is part of this development. A major turning point in the development of concrete and its properties occurred with the use of new, more efficient plasticizing additives. This allowed to produce concrete with lower water cement ratio, while increasing the strength of concrete. Gradually, the compressive strength of concrete boundary has moved by several levels, when there are currently commonly used concrete with strength of about 100 N/mm2 and with the special methods of concrete production strength range from 250 to 300 N/mm2. A negative aspect of the development of (ultra) high-strength concrete is their energy and economic demands. A characteristic feature of high-strength concrete is a high content of cement and very fine admixtures, especially silica fume. One way to improve the economics of these types of concrete is the application of cheaper admixture based on industrial waste. The content of this work is the observation and description of the properties of high-strength concrete and reactive powder concrete, in which the admixtures were based on industrial waste were applied. Part of this work is the comparison of economic parameters for individual types of concrete.
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Balúch, Tomáš. "Autosalon." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2017. http://www.nusl.cz/ntk/nusl-265350.
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This master's thesis focuses on design and elaboration of documentation for construction of a Car Showroom. The building is divided to two functional parts. The building is to be situated on plot number 1333/21, cadastre unit: Bohunice. The building is to be located on an undeveloped plot in possesion of the investor. The parking lots are connected to a local road. All substantial infrastructures are located nearby the plot. The proposition and the design of the building have respect for both commune plan and current buildings. The documentation is elaborated with regard to the contemporary Czech legislative and standards. The project designs the building, which is divided in two functional parts: SO 01 & SO 02, both operationally and visually connected. Contructions of objects are structurally independent. The first object includes exhibition hall with capacity of 8 exhibited cars. There is also to be located the administrative part, waiting rooms for customers, facilities for employees and the warehouse. The second object includes car repair shop. There are also to be located facilities for employees of the service, workshop, room for a car handover, hand car wash and an utility room. Construction is designed as a reinforced concrete columnar structural system with prefabricated single footings, self-supporting foundation slab and reinforced concrete ceiling slab with integrated girders above first floor of the object SO 01. The roofs of the building are designed as a flat roofs and the support constructions are made of steel. Planned dimensions of autosalon are 41x18 metres. As a cladding of the first object is used the lightweight glass cladding. For masonry walls are used the 250 mm thick ceramic blocks, mineral insulation and ventilated external facade cladding with use of fiber-cement boards. Planned dimensions of car repair shop are 31x28 metres. As a cladding of the second object are used the sandwich panels with foam core made of PIR.
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Volk, Sergio. "O custo da captação de recursos nas empresas e o processo decisório desta captação no curto e longo prazo: estudo de caso de empresa do ramo cerâmico de Santa Catarina." Pontifícia Universidade Católica de São Paulo, 2008. https://tede2.pucsp.br/handle/handle/1687.
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Previous issue date: 2008-03-04The study of the decisions related to the structure of capital in the Brazilian market always motivates. Especially in Brazil where, the difficulties of raising long-term feature of financial market often leads companies to the debt shorter deadlines. Several studies and empirical evidence have shown that the decisions of the capital structure can affect the value of companies on the market, and evaluate the issue considering the imperfections in the market, such as taxes, cost of bankruptcy, cost of agency and asymmetry of information. Studied the forms and the cost of raising resources for the short and long term and the decision making that defines the capture of resources through case study of ceramic company in the industry of Santa Catarina. We note that the three theories that seek to explain the Temporal Structure of Interest Rates to which most closely approximates the Brazilian reality is the theory of segmentation of the market. That means policyholders and donors of funds are concentrated in certain segments of the yield curve and that the rates in different maturities are determined by conditions of supply and demand of the various market segments. The lack of savings of more mature in Brazil in sufficient volume to meet the investment needs of the economy leads to funding with resources official whose major donor is the National Bank of Economic and Social Development (BNDES), which practices interest rate lower than the private market. Since the cost of equity capital from third less than the cost of equity, the debt contributes to the reduction of the Weighted Average Cost of Capital, especially in the use of debt to long-term, as the interest in this company for the long term are less than the short-term. In the case study found an unusual shape to decrease the cost of capital of the company, which is the tax debt which further reduces the cost of capital
O estudo das decisões relacionadas à estrutura de capital no mercado brasileiro sempre motiva. Principalmente no Brasil onde, as dificuldades de captação de recurso de longo prazo no mercado financeiro muitas vezes levam as empresas ao endividamento a prazos mais curtos. Vários estudos e evidências empíricas têm demonstrado que as decisões de estrutura de capital podem afetar o valor das companhias no mercado, e avaliam a questão considerando as imperfeições no mercado, como impostos, custo de falência, custos de agência e assimetria de informações.Estudamos as formas e o custo de captação de recursos de curto e longo prazo e o processo decisório que define a captação dos recursos através de estudo de caso de empresa do ramo cerâmico de Santa Catarina.Constatamos que das três teorias que buscam explicar a Estrutura Temporal das Taxas de Juros a que mais se aproxima da realidade brasileira é a teoria da segmentação de mercado. Isso significa que tomadores e doadores de fundos se concentram em determinados segmentos da curva de rendimento e que as taxas em diferentes maturidades são determinadas pelas condições de oferta e demanda dos vários segmentos de mercado. A falta de poupanças de maior maturidade no Brasil em volume suficiente para atender às necessidades de investimentos da economia leva ao financiamento com recursos oficiais cujo grande financiador é o Banco Nacional de Desenvolvimento Econômico e Social (BNDES), que pratica taxa de juro inferior às do mercado privado. Sendo o custo de capital próprio de terceiros menor que o custo de capital próprio, o endividamento contribui com a redução do Custo Médio Ponderado de Capital, especialmente na utilização de endividamento de longo prazo, já que nesta empresa os juros de longo prazo são menores que as de curto prazo.No estudo de caso constatamos uma forma pouco usual de diminuição do custo de capital da empresa, que é o endividamento tributário que reduz mais ainda o custo de capital
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Vondrová, Michaela. "Dům pro seniory ve Velkém Poříčí." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2020. http://www.nusl.cz/ntk/nusl-410111.
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It is about new-built Retirement center standing alone in the cadaster unit of the town Velké Poříčí. The building has four- floors without basement. It is located in flat terrain near the river in quiet location. The house is built as letter L form. The Retirement center is adapt for disabled people. In the first floor is dining room, doctor´s office, part for employees and technical facilities for house. In the second and third floors are apartments. There are 12 single rooms for one person, 6 single rooms for pair with sleeping in one room and 4 apartments for couple with separated bedroom. In the fourth floor is access to roof terrace. The structural systém of the building is composed of precast concrete frame by Prefa, infill wall from ceramic masonry. Vertical structures are built by prestressed concrete floor slab Spiroll. The building has ventilated facade with mineral wool with facade cladding. The roof is warm flat roof with half intensive green roof.
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Fanti, Laura. "La fonction des récipients céramiques dans les sociétés du Néolitique moyen B (4500-4000 cal BC) en Sardaigne centre-occidentale (Italie) : Indices fonctionnels, économiques, interculturels à partir de l’analyse des caractéristiques morphométriques, des résidus organiques et des traces d’usure des poteries." Thesis, Nice, 2015. http://www.theses.fr/2015NICE2024.
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La Sardaigne, en raison de sa position géographique au cœur de la Méditerranée occidentale, constitue une zone clé pour la compréhension de la diffusion du Néolithique dans le domaine nord-tyrrhénien. La deuxième moitié du Ve millénaire cal BC marque l’essor et l’aboutissement du processus de diffusion de l’économie néolithique dans l’île, sous l’égide des groupes humains « San Ciriaco ». Des fouilles récentes dans la Sardaigne centre-occidentale, zone cruciale pour cette entité culturelle régionale, ont décelé des contextes inédits dont l’étude est fondamentale pour la connaissance de ces sociétés. Cette thèse se propose d’explorer le rôle des poteries dans les systèmes techniques et les comportements symboliques des groupes humains San Ciriaco en Sardaigne centre-occidentale, afin d’obtenir des indices économiques sur les stratégies de gestion des ressources et sur les modes de vie de ces populations. L’approche interdisciplinaire suivie combine l’analyse morphométrique des récipients, l’observation des traces d’usure et l’analyse chimique des résidus organiques (en CPG et CPG/SM) piégés dans la matrice céramique. Les résultats révèlent une structuration des assemblages céramiques en plusieurs gammes fonctionnelles, variablement représentées sur des sites à destination différente (habitat, sépultures, « dépôts » de vases). Des comportements techniques et symboliques liés à la gestion des récipients tout au long de leur cycle d’utilisation sont mis en lumière. Ces résultats offrent une première contribution à la plus large problématique de l’évolution de la fonction des poteries, tout au long du Néolithique, au sein du domaine méditerranéen occidental.zone cruciale pour cette entité culturelle régionale originale, ont décelé des contextes inédits dont l’étude s’avère être fondamentale pour la connaissance de ces sociétés. Cette thèse se propose d’explorer le rôle des poteries dans les systèmes techniques et les comportements symboliques des groupes humains San Ciriaco en Sardaigne centre-occidentale, afin d’obtenir des indices économiques sur les stratégies de gestion des ressources et sur les modes de vie de ces populations. L’approche interdisciplinaire suivie combine l’analyse morphométrique des récipients, l’observation des traces d’usure et l’analyse chimique des résidus organiques (en chromatographie en phase gazeuse et chromatographie en phase gazeuse couplée à la spectrométrie de masse), piégés dans la matrice céramique. Les résultats obtenus révèlent une structuration des assemblages céramiques en plusieurs gammes fonctionnelles distinctes et variablement représentées sur des sites à destination fonctionnelle différente (habitat, sépultures, « dépôts » de vases). Des comportements techniques et symboliques liés à la gestion des récipients tout au long de leur cycle d’utilisation sont également mis en lumière. Ces résultats offrent une première contribution à la plus large problématique de l’évolution de la fonction des poteries, tout au long du Néolithique, au sein du domaine méditerranéen occidentalThe isle of Sardinia (Italy) is a key zone in understanding the spread and the diffusion of the Neolithic in North Tyrrhenian region, due to its position in the middle of western Mediterranean Sea. Here, the rise and culmination of Neolithic economy is carried by San Ciriaco populations in the second half of V millennium cal BC. Recent archaeological excavations in central-western Sardinia revealed new contexts the study of which is fundamental in increasing our knowledge of these Neolithic societies.The aim of this work is to investigate the role of pottery in technical systems and symbolical behaviours of San Ciriaco societies in central-western Sardinia, in order to find evidence of strategies of use and explore their way(s) of life. The interdisciplinary approach in this study combines morphometrical analysis of vessels, use-wear observation and GC / GC-MS chemical analysis of organic residues absorbed in pottery.This research revealed a structuration of pottery assemblages into several functional categories which are differently represented in sites with a different function (settlements, burials, vessels “deposits”). The results contribute to highlight technical and symbolical behaviors linked to the use of pottery during its life cycle phases. These data offer a contribution to the issue of the evolution of pottery function during the Neolithic period in Western Mediterranean
La Sardegna, in virtù della sua posizione centrale nel Mediterraneo occidentale, rappresenta una zona cruciale per la comprensione del processo di propagazione del Neolitico e della sua evoluzione nell’area nord-tirrenica. Il pieno sviluppo dell’economia neolitica nell’isola è segnato dalla formazione e diffusione di un’entità culturale regionale originale, denominata “cultura di San Ciriaco”, durante la seconda metà del V millennio cal BC (Neolitico Medio B). Alcuni recenti scavi nella Sardegna centro-occidentale, scenario fondamentale nello sviluppo di tale entità culturale, hanno portato alla luce dei contesti inediti, il cui studio si rivela essenziale per la conoscenza di queste società neolitiche.L’obiettivo di questa ricerca è specificamente quello di indagare il ruolo dei recipienti ceramici nei sistemi tecnici e nei comportamenti simbolici dei gruppi umani San Ciriaco della Sardegna centro-occidentale, nell’intento di acquisire degli indizi sulle strategie di gestione delle risorse naturali e sulle modalità di sussistenza delle popolazioni durante il Neolitico medio B.L’approccio interdisciplinare seguito associa l’analisi morfometrica dei recipienti all’osservazione delle tracce d’uso e all’analisi chimica dei residui organici assorbiti nella matrice ceramica, mediante la tecnica della gascromatografia (GC) e della gascromatografia/spettrometria di massa (GC/MS).I risultati ottenuti rivelano una strutturazione delle collezioni ceramiche in molteplici gamme funzionali distinte e variabilmente rappresentate in siti con destinazione funzionale differente (abitato, sepolture, “depositi” di recipienti). L’analisi di tali contesti ha permesso di evidenziare alcuni specifici comportamenti tecnici e simbolici legati alla gestione dei recipienti durante tutto il loro ciclo d’utilizzo.L’interpretazione storica dei dati acquisiti con questa ricerca offre un contributo alla più vasta questione dell’evoluzione della funzione dei recipienti ceramici, nel corso del Neolitico, nell’area del Mediterraneo occidentale
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Spurný, Martin. "Wellness hotel "Na Ovčačce" - Svatý Kopeček u Olomouce." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2017. http://www.nusl.cz/ntk/nusl-265373.
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The project is newly built wellness hotel in the cadastral Svatý Kopeček, the town of Olomouc, district Olomouc. The house is in a secluded street in Darwin. On the territory are restrictions concerning the parameters solved object. Notably the location, number of floors and the percentage of stopping. This is a three-storey, basement building with a flat roof. The building is based on the footings of plain concrete and reinforced concrete footings. Supporting, peripheral and partition walls are designed from ceramic blocks POROTHERM in the upper floors of concrete formwork and fittings in the basement. Ceiling structure is designed using locally supported reinforced concrete slabs. The entire building is divided into several sections. The 1s there is an underground garage and wellness. In 1.NP is a restaurant and facilities associated with the operation of the restaurant and hotel. In 2.NP and 3.NP are single rooms. Total capacity is 155 people and has 16 employees. To the building are three main entrances. Two of them are designed as public entrance to the restaurant and hotel. The third is the entrance for staff and supplies. Among other inputs that lead from the exterior of the building is the entrance to the restaurant terrace. Another entry is possible from the underground garage to wllnessu. The proposed facility is designed wheelchair. Before the building is designed parking for 27 cars and underground garage for 44 cars. Five of parking places are for disabled people.
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Ojala, Karin. "I bronsålderns gränsland : Uppland och frågan om östliga kontakter." Doctoral thesis, Uppsala universitet, Institutionen för arkeologi och antik historia, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-308474.
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In archaeological research, the province of Uppland has often been viewed as the northern ‘periphery’ of the Nordic Bronze Age region. At the same time, many researchers have also emphasized the distinctive and ‘independent’ regional character of Uppland and northern Mälardalen. Throughout the twentieth century, Late Bronze Age contacts between Uppland and areas to the east – especially Finland, the Baltic countries and Russia – were much discussed and played an important role in the creation of Mälardalen as a distinctive Bronze Age region. This dissertation examines how images of the Late Bronze Age in the Mälardalen region, more specifically Uppland, have been formed from the late nineteenth century until today, and how views on eastern contacts have affected interpretations of Bronze Age Uppland. The study consists of three parts: 1) A critical discussion on political dimensions of archaeology and archaeological concepts of contact, interaction, similarity and difference, with a special focus on Bronze Age research. 2) A historical examination of representations of the Late Bronze Age in Mälardalen and Uppland, including a discussion about contacts with northern Sweden and a case study of Broby, a Late Bronze Age site near Uppsala. 3) An analysis of debates on contacts between Mälardalen and areas further to the east, through case studies of bronze axes, so-called Mälar celts and Ananino celts, ceramics and inhumation burials. In the analysis, special focus is placed on the Volga-Kama region in Russia and archaeological research in Russia and the Soviet Union. The study shows that discussions on contacts and interaction between ‘East’ and ‘West’ have, in many ways, been affected by the changing political situation during the twentieth and early twenty-first centuries. Knowledge about archaeological research in Russia and the Soviet Union has been very limited among archaeologists in Sweden. In order to further investigate the character and importance of eastern contacts during the Late Bronze Age, more collaboration and exchange between researchers in the different countries is needed. Furthermore, in order to better understand eastern contacts, it is also necessary to investigate in greater depth the relations between Mälardalen and northern Sweden.
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Lee, Hsin-Ying, and 李欣穎. "Mountain, Sea and Ceramics – The study of Ceramic Craft Applied to Taitung Agricultural Product Containers." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/05341355650232086575.
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碩士國立臺東大學
美術產業碩士學位在職進修專班
102
Taitung County is located at southeast corner of Taiwan, including two offshore islands-Green Island and Lan Yue, with geographic position at south of the Tropic of Cancer and facing the Pacific on the east. From point of view for the historical geography, its independent geographic areas as well as soaring and continuous Central Mountains block this area in the Pacific coast, which is usually referred to as “Back Mountain”. In addition to reserving primitive and simple rural landscape, it has unique, rich and distinctive local agricultural products. The writer personally intended to explore antitheses between natural landscape of mountain and sea and ceramics in connection with local image. Therefore, ceramic craft creation combined with features of local agricultural products is used as basis to develop containers of local agricultural products, establishing commercialization and lifestyle for features of local agricultural products through artistic creation, and discussing the feasibility of the development for local agricultural product containers in Taitung County. Purposes of the study are to: 1. Discuss the development of Taiwan’s pottery and ceramics; 2. Explore the creative ideas on pottery containers; 3. Make pottery creation on Taitung agricultural products and containers. In recent years, the writer of this study tried transforming his creations with aesthetic concept for the package of Taitung agricultural products to artworks of life, and presenting Taitung agricultural products with the closest natural creative way. The writer anticipated that this way can promote multiple creation-base arts and ideas to develop agricultural products with Taitung image, and facilitate Taitung’s competiveness; moreover, people is expected to concern more about the technique and feature for the basis of future creations of ceramic craft creation. The study indicates that ceramic craft applied to agricultural product container as the theme could integrate ceramic craft creation into agricultural products for more energy motivated by innovative marketing through ceramic craft technique for Taitung agricultural products. Meanwhile, this will be a touchstone that combination of ceramic craft creative technique and special agricultural products is used to develop both art industry and agriculture, expecting to light the new hope for development prospect of creation and agricultural product container
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Walker, Stuart J. "Multi-mode cavity effects in the microwave heating of a ceramic slab." Thesis, 2001. http://library1.njit.edu/etd/fromwebvoyage.cfm?id=njit-etd2001-088.
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Weng, Pei-Ya, and 翁珮雅. "Effects of Fe2O3 on Manufacturing Insulating Glass-Ceramic from TFT-LCD Waste Glass and Basic Oxygen Furnace Slag." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/91499759048196070401.
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碩士國立臺灣大學
環境工程學研究所
100
The objective of this research was to use thin film liquid crystal display (TFT-LCD) waste glass and basic oxygen furnace (BOF) slag as recycled materials to produce insulating glass-ceramic by thermal treatment. In addition, the effects of Fe2O3 content in the BOF slag on the insulating glass-ceramic’s crystalline phase, mechanical, dielectric and thermal expansion properties were also experimented and discussed in details. There were three experimental stages conducted in this study. The first stage was to fix the weight ratio of TFT-LCD waste glass to BOF slag by adding pure reagent of Fe2O3 in order to analyze the relevance of Fe2O3 content to the characteristics of the products, such as crystalline phase, mechanical and dielectric properties. The second stage was to adjust the input ingredients of BOF slag which contains various Fe2O3 content to produce insulating glass-ceramic with excellent mechanical and dielectric properties. The third stage was to analyze the consistency of the effects of Fe2O3 on the production of insulating glass-ceramic from the first and second stage. The results indicated that Fe2O3 could act as nucleating agent to promote crystallization at lower thermal treatment temperature and stimulated the formation of a wide variety of crystal types. In addition, increase in Fe2O3 content would enhance glass-ceramic’s mechanical properties including density and flexural strength. However, dielectric properties did not improve with Fe2O3 addition. When TFT-LCD waste glass and BOF slag was blended in the ratio of 7:3 while BOF slag was prepared with pre-BOF slag and post-BOF slag in the ratio of 5:5, under heat treatment temperature of 820℃, the insulating glass-ceramic exhibited satisfactory characteristics with product density (2.64 g/cm3), bending strength (110 MPa), dielectric constant (8.8), dissipation factor (0.0043), quality factor (235), and dielectric loss factor (0.037). The final product of glass-ceramic had good mechanical strength and dielectric properties. Therefore, this research concluded that the adjustment of the pre/post BOF slag ratio would effectively improve insulating glass-ceramic properties and achieve the goal of reducing the use of additional material and energy. According to the results of first and second stage, it demonstrated that the differences of crystalline phase, mechanical and dielectric properties caused by the Fe2O3 content were consistent. Therefore, it is promising to manufacture insulating glass-ceramic from TFT-LCD waste glass and BOF slag, in which Fe2O3 would play one of the main affecting factors.
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Hsu, Wen-Hao, and 徐文浩. "Rain Forests Of The Sea - an artistic narrative about using ceramic art to explore coral reef ecological conservation." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/5vb2d3.
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碩士國立東華大學
藝術創意產業學系
107
Oceans, the “Blue Heart” of the planet, cover approximately 70% of Earth’s surface is the largest life-support system on Earth. As the “rainforests of the sea”, coral reefs have been an important indicator in studying biodiversity. However, reefs have suffered from mass coral bleaching events as the result of the increase in greenhouse gas emissions. Ocean warming caused a large number of coral bleaching deaths, which consequently threaten other ecosystems. The fragile coral reef ecological environment needs to be revived. I will transform the elements of the marine life that I love in my memory and the delicate shells and skeletons of the ocean microfossils. To focus on rep roducing the beauty of coral reefs, delicate shells and skeletons of marine microfossils were used as elements for transformation, and was then shaped with the Hualien's Dongfu clay produced by the Tafalong tribe. "Rainforests Of The Sea "split into three topics, "Worry aboud the coral bleaching ", "Illusion march of microfossils " and "A hall of ocean treasure". The sadness and sorrow feelings for coral bleaching were presented through three series of pottery creations, in the attempt to highlight the importance of the conservation of marine lives.
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Lee, Hsin, and 李新. "Materialization Study on Glass-Ceramic from TFT-LCD Wasted Glass Mixing with Basic Oxygen Furnace Slag by TwoStage Heat Treatment." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/25937674496671343850.
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碩士國立臺灣大學
環境工程學研究所
99
Abstract The influence of two-stage heat treatment and additives like MgO、Al2O3 on the dielectric properties and mechanical properties of glass-ceramics made from a combination of TFT-LCD(Thin Film Transistor Liquid Crystal Display) waste glass and Basic Oxygen Furnace Slag(BOF) is investigated. The system of glass-ceramic shifted from CAS to MAS system was through 20%(w/w) MgO and 20%(w/w) Al2O3 added into the martrix(TFT-LCD waste glass: BOF=7:3). The experiment demonstrated that the density increased with temperature increase. Moreover, both adding additives and two-stage heat treatment improved mechanical properties due to production of forsterite crystal. Under two-stage heat treatment process with 640℃ for 2 hours followed by 980℃ for 30minutes, a material with high density (2.91 g/cm3),high bending strength (256MPa), high compressive strength(717MPa) ,low dielectric dielectric constant(7.59) and low dielectric loss factor(0.097) were resulted, which met the required standard of insulated glass-ceramic.
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Huang, Shu-Chen, and 黃淑貞. "Kinetic and characteristic study on glass-ceramics produced from slag of municipal solid waste incinerator fly ash." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/07917224511111242245.
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碩士逢甲大學
環境工程與科學所
96
Abstract This study investigates that the feasibility of glass ceramic products made from molten slag of municipal solid waste incinerator (MSWI) fly ash and waste glass cullet. The experiments were conducted at melting temperature 1450℃ and sintering-crystallization temperatures ranged from 900 to 1100℃. To assess the characteristics of glass-ceramic products and optimum operation conditions, the activation energy of melting an sintering reaction were also evaluated. Based on the results of activation energy of melting process, the melting temperature of MSWI fly ash is higher than 1350℃. However, in case of the waste glass cullet addition above 30%, the melting temperature will be decreased to 1285℃. That is, the waste glass addition will enhance the reaction of melting and reduce the melting temperature. Meanwhile, the activation energy of melting decreased from 109.9 kJ/mole to 23.5 kJ/mole with an increase in waste glass cullet addition ranged from 30% to 50%.The TCLP concentrations of Cu、Zn、Cr、Cd and Pb in slag were all in compliant with Taiwan regulation thresholds. Besides, the results of residual rate of tested metals of slags, the residual rate of Cd, Pb and Zn were approximately 0%. The experimental results of glass ceramic products indicated that the water absorption and compressive strength of glass-ceramic (slag produced from 30% waste glass cullet addition) were 11.29%~14.03% and 20.32 MPa~25.92 MPa, respectively. In case of slag produced from 50% waste glass cullet addition, the water absorption and compressive strength of glass ceramic products were 13.54% and 27.23MPa, respectively. The above results were all in compliant with Chinese National Standard (CNS) building brick criteria for construction work. Besides, the major speciation of glass ceramic products were Gehlenite (Ca2Al2SiO7), Augite-aluminian (Ca(Mg,Fe,Al)(SiAl)2O6), Augite (Ca(Mg,Fe)Si2O6), Diopside (Ca(Mg,Al)(Si,Al)2O6), and Wollastonite (CaSiO3), respectively. According to results of linear swelling analysis and activation energy, the maximum swelling value (dL/dt) of slag increased from 1.83% ~2.53% to 3.71%~5.07% with waste glass cullet addition increased from 30% to 50%. The activation energy of sintering also increased from 22.00 kJ/mole~24.34 kJ/mole to 39.09 kJ/mole~52.56 kJ/mole with an increase in waste glass cullet addition. That is, the activation energy of sintering increased with waste glass cullet addition increased. The assessment for environmental safety of glass ceramic products was conducted by the toxic characteristic leaching procedure (TCLP) concentration and acid neutralization capacity (ANC). The TCLP concentrations of Cu, Zn, Cr, Cd, and Pb were lower than regulation thresholds. The results of ANC test showed that the used amounts of acid titration were ranged from 8.18 meq/g to 12.56meq/g as pH = 4. The maximum released amounts of Cr、Pb and Cu of glass ceramic products (slags produced from 40% and 50% waste glass cullet addition) were 0.002 mg/meq•kg ~3.51 mg/meq•kg, 0.001 mg/meq•kg~0.008 mg/meq•kg, and 0.001 mg/meq•kg~1.434 mg/meq•kg, respectively. The released amounts of tested metals of glass ceramic products were far below the maximum released amounts of MSWI fly ash (3.70 mg/meq•kg for Cr, 94.37 mg/meq•kg for Pb, and 25.31 mg/meq•kg for Cu).
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Lin, Tung-Hung, and 林東宏. "Materialization Study on Transformation of Insulated Glass-Ceramic from Mixing TFT-LCD Waste Glass and Basic Oxygen Furnace Slag by Thermal Treatment." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/59516510494676371014.
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碩士國立臺灣大學
環境工程學研究所
98
The objective of this study was to use thin film liquid crystal display (TFT-LCD) waste glasses from optoelectronic industry and basic oxygen furnace (BOF) slags from integrated steel plant as reused materials to produce insulated glass ceramic materials that have superior dielectic and mechanical properties with low coefficient of thermal expansion . This study selected the ratio of TFT-LCD waste glass to BOF slag as 6：4 and 7：3 by weight based on quenched vitreous slag composition which has the feasibility to initiate good insulating properties of MgO-Al2O3-SiO2 (MAS) glass ceramic system. The vertification of MAS glass-ceramic system was conducted by addition of 10-20 % MgO (w/w)、15-20 % Al2O3 (w/w) and 10 % TiO2 (w/w) , and analysed the effect of addition of modifier on crystal phases and thermal treatment temperature. In addition,regarding property analysis corresponding to the ratio of TFT-LCD waste glass to BOF slag as 7：3 (w/w) with various proportions of modifier, the effect of temperature on thermal properties and mechanical properties as well as the assessment of potentiality of material reultilized from mixing TFT-LCD waste glass and BOF slag which formed the insulating glass-ceramics were investigated . The results showed that the ratios were precipitated crystalline via heat treatment when TFT-LCD waste glass and BOF slag in the ratio of 7：3 with addition of 20 % MgO and 15-20 % Al2O3 (w/w) , which contained anorthite and wollastonite in the CaO-Al2O3-SiO2 (CAS) , forsterite and cristobalite in the MgO-Al2O3-SiO2 (MAS) system. The above crystalline phases in glass-ceramic systems are consequently suitable for thermal shock resistant and insulation. Besides the production of crystalline phases in lower temperature, it also contributed to phase separation and crystal growth due to addition of TiO2. But TiO2 addition resulted in the decrease of phase relative intensity of forsterite in MgO-Al2O3-SiO2 (MAS) system,it also indirected affected the specimens on thermal and mechanical properties. The optimal operational conditions to reutilize wastes as insulating glass ceramics could be found as follows. (1)TFT-LCD waste glass and BOF slag in the ratio of 7：3 with MgO addition of 15-20 % and Al2O3 addition of 20 %. (2)The resulted low coefficient of thermal expansion similar to microchip’s which could be applied to electronic ceramic package.(3)One-step sintering and heat treatment at 980 ℃ for 0.5h could be employed to obtain glass-ceramics with flexural strength up to about 257.6 MPa and compressive strength up to about 732 MPa. Mechanical properties will influence the yield on glass-ceramic process in pratical operation, and the sintered materials could meet the required properties in the range between 860 ℃and 900 ℃.
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Lee, Chen-Fang, and 李承芳. "nfluences of Particle Size and Sintering Time on Insulating Glass Ceramics Sintered from TFT-LCD Waste Glass and BOF Slag." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/91944096747190461582.
Full textAbstract:
碩士國立臺灣大學
環境工程學研究所
100
The study aims to decide the optimal heat treatment for reusing the glass ceramics in insulating. Influence of particle size: D1(D50:11 μm), D2(D50:25 μm), D3(D50:59 μm) and sintering time: 0.5 hour, 1 hour, 2 hours on physical properties, dielectric properties and bending strength are considered. The glass ceramics sintered from TFT-LCD waste glass (Thin Film Transistor-Liquid Crystal Display) mixed BOF slag (Basic Oxygen Furnace Slag) with weight ratios 7:3, adding 15 wt% MgO and 15 wt% Al2O3. The main crystalline are enstatite(MgSiO3), anorthite(CaAl2Si2O8), wollastonite(CaSiO3) and forsterite(Mg2SiO4). Results show that glass ceramics of D1 and sintering 2 hours ocurr densification, crystallization and higher bending strength at lower temperature. Before crystallization, dielectric constant and quality factor (Q factor) of D1 is higher because glass ceramics of D1 are much denser. After crystallization, there are no effects of particle size on dielectric constant, but Q factor decreases about 80%. However, as sintering temperature rise and crystalline having high Q factor appear, Q factor increases smoothly. Moreover, longer sintering time causes the occurrence of enstatite, which lead to Q factor drops and coefficient of thermal expansion increase. On the effect of particle size, D1 performe better in bending strength and Q factor than D2. On sitering time, though longer sintering time lead to higher bending strength, Q factor cannot increase during temperature rising. As a result, D1, 900°C, 0.5hour which have well bending strength 158.8MPa, dielectric constant 10.2 and Q factor 100.1 is the most suitable heat treatment for insulating glass ceramics. On the aspect of reusing, smaller particle is more effective and economics than longer sintering time.
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Herrera, Catalina. "Optimization of O3 as Pre-Treatment and Chemical Enhanced Backwashing in UF and MF Ceramic Membranes for the Treatment of Secondary Wastewater Effluent and Red Sea Water." Thesis, 2011. http://hdl.handle.net/10754/209410.
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Ceramic membranes have proven to have many advantages over polymeric membranes. Some of these advantages are: resistance against extreme pH, higher permeate flux, less frequent chemical cleaning, excellent backwash efficiency and longer lifetime. Other main advantage is the use of strong chemical agent such as Ozone (O3), to perform membrane cleaning. Ozone has proven to be a good disinfection agent, deactivating bacteria and viruses. Ozone has high oxidation potential and high reactivity with natural organic matter (NOM). Several studies have shown that combining ozone to MF/UF systems could minimize membrane fouling and getting higher operational fluxes.
This work focused on ozone – ceramic membrane filtration for treating wastewater effluent and seawater. Effects of ozone as a pre – treatment or chemical cleaning with ceramic membrane filtration were identified in terms of permeate flux and organic fouling. Ozonation tests were done by adjusting O3 dose with source water, monitoring flux decline and membrane fouling. Backwashing availability and membrane recovery rate were also analyzed. Two types of MF/UF ceramics membranes (AAO and TAMI) were used for this study. When ozone dosage was higher in the source water, membrane filtration improved in performance, resulting in a reduced flux decline. In secondary wastewater effluent, raw source water declined up to 77% of normalized flux, while with O3 as pre – treatment, source water at its higher O3 dose, flux decreased only 33% of normalized flux. For seawater, membrane performance increase from declining to 37% of its final normalized flux to 21%, when O3 as a pre – treatment was used. Membrane recovery rate also improved even with low O3 dose, as an example, with 8 mg/L irreversible fouling decreases from 58% with no ozone addition to 29% for secondary wastewater effluent treatment. For seawater treatment, irreversible fouling decreased from 37% with no ozone addition to 21% at 8 mg/L, proving ozone is a useful chemical to be used as pre – treatment for both source waters. Finally, transparent exopolymer particles (TEP) showed a decrease in concentration on the active layer of the membrane surface after chemical enhanced backwashing (CEB) using ozone (O3).
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Braun, Kathy J. Ward Cheryl A. "A cargo of Islamic ceramics from the eighteenth-century Sadana Island shipwreck in the Red Sea typology, form, and function of Qulal and other shapes /." Diss., 2005. http://etd.lib.fsu.edu/theses/available/etd-07082005-170419.
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Thesis (M. A.)--Florida State University, 2005.Advisor: Dr. Cheryl A. Ward, Florida State University, College of Arts and Sciences, Dept. of Anthropology. Title and description from dissertation home page (viewed Sept. 19, 2005). Document formatted into pages; contains ix, 161 pages. Includes bibliographical references.
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Bourgela, Samuel. "Les céramiques et les réseaux maritimes du fort de Ville-Marie, Montréal, 1642-1688." Thèse, 2018. http://hdl.handle.net/1866/21572.
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