Compositionally related glasses and ceramics of the Na$ sb2$O$ cdot$CaO$ cdot$Al$ sb2$O$ sb3 cdot$TiO$ sb2 cdot$SiO$ sb2$ system (sphene glass-ceramics) doped with Eu$ sp{3+}$ were examined using site-selective spectroscopic techniques (FLN). In sphene glass-ceramics, Eu$ sp{3+}$ preferentially partitions into the crystalline sphene phase. The partition ratio is concentration dependent, decreasing at higher concentrations, because of the limited solid solubility of Eu$ sp{3+}$ in sphene. The concentration occurs at the time of phase separation; Eu$ sp{3+}$ preferentially enters the more ionic (CaO, TiO$ sb2$)- rich droplet phase which eventually becomes sphene. In sphene, Eu$ sp{3+}$ substitutes for Ca$ sp{2+}$ appearing in three different sites caused by associated charge compensation defects. From an analysis of the FLN spectra of the different glasses, the framework for a model describing the coordination shell of Eu$ sp{3+}$ in oxide glasses is developed. The model suggests that Eu$ sp{3+}$ behaves as a network forming ion or quasi-molecular complex. The model is used to explain qualitative features of Eu$ sp{3+}$ FLN spectra including the dependence of the clustering of points of the major crystal field parameter ratios plot on the relative number of non-bridging oxygen ions and Eu$ sp{3+}$ ions in the glass.

Low temperature co-fired ceramic (LTCC) electronic packaging materials are applied for their electrical and mechanical properties, high reliability, chemical stability and ease of fabrication. Three dimensional features can also be prepared allowing integration of microfluidic channels and cavities inside LTCC modules. Mechanical, optical, electrical, microfluidic functions have been realized in single LTCC modules. For these reasons LTCC is attractive for biomedical microfluidics and Lab-on-a-Chip systems. However, commercial LTCC systems, optimized for microelectrics applications, have unknown cytocompatibility, and are not compatible with common surface functionalization chemistries. The first goal of this work is to develop biocompatible LTCC materials for biomedical applications. In the current work, two different biocompatible LTCC substrate materials are conceived, formulated and evaluated. Both materials are based from well-known and widely utilized biocompatible materials. The biocompatibilities of the developed LTCC materials for in-vitro applications are studied by cytotoxicity assays, including culturing endothelial cells (EC) both in LTCC leachate and directly on the LTCC substrates. The results demonstrate the developed LTCC materials are biocompatible for in-vitro biological applications involving EC. The second goal of this work is to develop functional capabilities in LTCC microfluidic systems suitable for in-vitro and biomedical applications. One proposed application is the evaluation of oxygen tension and oxidative stress in perfusion cell culture and bioreactors. A Clark-type oxygen sensor is successfully integrated with LTCC technique in this work. In the current work, a solid state proton conductive electrolyte is used to integrate an oxygen sensor into the LTCC. The measurement of oxygen concentration in Clark-type oxygen sensor is based on the electrochemical reaction between working electrode and counter electrode. Cyclic voltammetry and chronoamperometry are measured to determine the electrochemical properties of oxygen reduction in the LTCC based oxygen sensor. The reduction current showed a linear relationship with oxygen concentration. In addition, LTCC sensor exhibits rapid response and sensitivity in the physiological range 1─9 mg/L. The fabricated devices have the capabilities to regulate oxygen supply and determination of local dissolved oxygen concentration in the proposed applications including perfusion cell culture and biological assays.

Ceramic material culture recovered from archaeological sites has more to offer the researcher than placing the site or strata into a cultural historic timeline. By examining the characteristics of ceramics manufactured during the Woodland Period in southern Kentucky, this thesis answers questions related to the behavior of the potters who lived and worked there. Using the theoretical basis of ceramic ecology and technological choice, this thesis examines the choices made by the potters of two sites, the Long (15Ru17) and Rowena (15Ru10) sites, located along the Cumberland River in Russell County, Kentucky. The two sites are also compared to one another and similar assemblages in the Upper Cumberland River Valley, in terms of temporal occupation and utilization of tempering resources. Ultimately, the potters who occupied the Long and Rowena sites during the Woodland Period used locally available materials to temper their clay, even as they emulated other ceramic types. In terms of the two sites themselves, it appears that while they were not occupied by the same population of potters, they did employ similar tempering agents and stylistic types. Examining the behavior of potters who occupied these two sites informs the researcher about the behavior of the larger region of the Upper Cumberland Valley.

Alexandre Brongniart was known for his work as an important geologist and as an administrator at the Sèvres Porcelain Manufactory, but his roles as art historian and museologist are overlooked. Brongniart created a holistic methodology taken directly from science and applied it to ceramic art of all cultures and eras. He had a uniquely modern perspective on time, world culture, and archeology. Brongniart wrote about the art of Asia and the Americas on an equal status with that of the Classical West at least fifty years before it became a mainstream idea. Brongniart integrated scientific principle and practice into the structure of the Sèvres Museum and a comprehensive set of books which includes Traité de Mineralogie avec des Applications aux Arts, Traité des Arts Ceramiques, and Description Methodique du Musée Ceramique de la Manufacture Royale de Porcelain de Sèvres. Numerous historians were influenced by Brongniart’s work, including Samuel Birch and Albert Jacquemart. Notably, the art historian Gottfried Semper refocused his ideas for Style in the Technical and Tectonic Arts after seeing the completed works of Brongniart. Although contemporary historians credit Semper with the development of a scientific approach to art history, Semper himself frequently acknowledged the importance of Brongniart’s work.

I mötet mellan händer och lera har en serie skålar i stengods tagit form som är riktade till den som yrkar ensamätandet. Arbetet är en strävan efter att ta fram emotionellt hållbara produkter där funktion kombinerats med interaktion för att utmana ätandet och ge en annorlunda matupplevelse.   Skålarna med sin runda botten kan behöva lite hjälp att hålla balansen vilket medför att du måste ta hand om skålen och maten du äter.  Tanken är att användaren enkelt med en hand ska kunna hålla skålen och om du vill ställa ifrån dig får du göra det försiktigt. Min önskan är att skålarna ska vara så pass tilldragande att användaren knyter an till skålen och gör den till sin egen. / Hold me is a project that aspires to bring out emotionally sustainable products were function has been combined with interaction for an altered experience of eating. The meeting between clay and hands has resulted in a series of bowls which are designed for people who eat alone.   The bowls with their round bottom may need some help to keep their balance which means you care for the bowl and the food you eat. The idea is that you easily, with one hand can hold your bowl and if you want to set it aside, you do it gently. My wish is that the bowl will be so appealing that the user connects to it and makes it their own.

Pour répondre aux nouvelles contraintes économiques et environnementales auxquelles l'industrie doit faire face aujourd'hui, des techniques de frittage rapide se développent pour la fabrication des céramiques. Parmi elles, une technique prometteuse est le frittage par micro-ondes dans laquelle le champ électromagnétique à l'origine du chauffage pourrait permettre d'obtenir des microstructures innovantes, tout en réduisant la température, le temps de cycle et la consommation énergétique. Pour expliquer le comportement particulier des poudres en présence des micro-ondes, différentes théories prévoyant des effets thermiques ou non-thermiques ont été proposées. L'existence même de ces effets n'a cependant toujours pas été démontrée de façon sûre, notamment à cause des limites des dispositifs expérimentaux qui ne permettent pas une comparaison pertinente du frittage micro-ondes avec le frittage conventionnel. Dans ce contexte, les travaux réalisés pendant cette thèse, dans le cadre du projet ANR Fµrnace, ont été consacrés à la mise en évidence et à la compréhension de l'influence du champ électromagnétique sur les mécanismes responsables de la densification et de l'évolution microstructurale de poudres céramiques. Une forte attention a été portée au développement technologique de la cavité de chauffage micro-ondes monomode utilisée dans nos recherches. Le procédé a été entièrement automatisé et équipé de divers systèmes de contrôle de la température et du retrait des échantillons pour que les résultats obtenus puissent être comparés de façon incontestable avec ceux issus d'essais de frittage conventionnel. Des simulations numériques ont été réalisées pour améliorer la compréhension de la propagation du champ électromagnétique et de son interaction avec les éléments introduits au sein de la cavité micro-ondes. Un matériau de référence, l'alumine, a été choisi et l'influence de certaines caractéristiques des poudres (surface spécifique, présence de dopants, transformation de phase) sur les cinétiques de densification et l'évolution microstructurale a été étudiée. Les résultats obtenus ont permis d'identifier des effets spécifiques des micro-ondes sur les mécanismes de diffusion responsables de la densification et de la croissance granulaire. Ces effets se produisent principalement pendant les stades initial et intermédiaire du frittage, ainsi que pendant la transformation de phase de poudres de transition et ont été attribués à une force de type pondéromotrice déjà proposée dans la littérature. L'utilisation de cette technique de frittage n'a cependant pas permis d'obtenir des alumines avec des microstructures plus performantes que celles issues du frittage conventionnel. / To meet the new economic and environmental constraints that the industry faces today, fast sintering processes are developed for the fabrication of ceramics. Among them, a promising technique is microwave sintering, in which the electromagnetic field at the origin of heating could be used to obtain innovative microstructures, while reducing sintering temperature, cycle time and energy consumption. To explain the particular behavior of powders under microwaves, different hypotheses related with thermal or non-thermal effects have been proposed in the literature. These effects, however, has not really been demonstrated for the moment, especially because of the limits of experimental devices that do not allow for a meaningful comparison of microwave sintering with conventional sintering. In this context, the work performed during this thesis in the framework of FμRNACE ANR project has been dedicated to identifying and understanding the influence of the electromagnetic field on the mechanisms of densification and microstructure changes in ceramic powders. High attention has been paid to the technological development of the single-mode microwave cavity used in our research. The heating process has been fully automated and instrumented with various equipments allowing for temperature and sample shrinkage measurement. The aim was to ensure direct and reliable comparison of microwave sintering data with those resulting from conventional sintering. Numerical simulation has been conducted to improve our understanding of the propagation of the electromagnetic field and its interaction with the components introduced in the microwave cavity. Alumina has been chosen as a reference material and the influence of several features of the powders (specific surface area, doping elements, phase transformation) on densification kinetics and microstructure changes has been studied. The results have identified specific effects of microwaves on the mechanisms controlling densification and grain growth. These effects occur essentially during the initial and intermediate stages of sintering and during the phase transformation of transition powders. They have been attributed to the ponderomotive force as already proposed in the literature. However the use of microwaves as a heating mode does not permit obtaining alumina with better microstructures than those resulting from conventional sintering.

Keramikos studijos – informatyvus šaltinis archeologiniams paminklams pažinti. Pasirinkta šio darbo tema apima Kernavės viduramžių apžiestą keramiką. Pagrindinis darbo tikslas – pasekti Kernavės keramikos raidą viduramžių Kernavės miesto ir vėliau čia egzistavusio miestelio chronologinėse ribose. Didžiausias dėmesys skiriamas XIII-XIV a. puodininkystės raidos tendencijoms stebėti, tuo tarpu miestelio keramika naudojama daugiau kaip lyginamoji medžiaga pokyčių stebėjimui ir išryškinimui. Tikslo įgyvendinimui tyrinėti technologiniai, morfologiniai, puošybiniai keramikos požymiai, stebėtas jų stabilumas ar kaita laike ir erdvėje, įvertinta šių požymių reikšmė. Didžiąją dalį nagrinėjamos Kernavės keramikos sudaro įvairių dydžių puodai, kurie sąlygiškai suskirstyti į funkcines grupes: mažus puodelius, puodus, puodynes, galėjusius atlikti maisto gamybos, pernešimo, saugojimo funkcijas. Specializuotų apžiestos keramikos indų sutinkama retai - dauguma jų priklauso miestelio laikotarpiui Technologinių gamybos požymių kaita aptariamu laikotarpiu nėra žymi. XIII-XIV a. pokyčiai dažniau pastebima ne diachroninėje, o erdvinėje plotmėje. Molio liesinimui dažniausiai naudotas grūstas granitas, sienelės formuotos iš volelių, o XIV a. ir iš juostų, apžiedžiant puodui buvo suteikiama forma ir/ar nulyginamas paviršius. XIV a. II p. keramikoje pastebima kiek spartesnė gamybinių požymių kaita – smulkėja priemaišos, puodai apžiedžiami intensyviau, sienelių storis tolygesnis, jos kruopščiau... [toliau žr. visą tekstą] / The subject of this study is medieval wheel-turned pottery of Kernavė. The main goal of this work is to observe the development of pottery of medieval town and later settlement of Kernavė. Particular attention is paid to the pottery making traditions in 13th-14th centuries. Pottery from the later settlement meanwhile is used mainly as the comparative material in order to observe some changes through time. Technological, morphological and ornamental properties of pottery were identified for the study of their significance and evolution through time and space. The majority of pottery under consideration can be attributed to the pots of different sizes. These pots were differentiated into several functional groups: small pots, pots and jars. All these groups could be used for a variety of purposes such as cooking, transportation or storage. The amount of single-purpose vessels is very small and even these few belong to the settlement which was established in the 15th century in the place of earlier town. The evolution of technological attributes of Kernavė’s pottery in the Middle-ages is quite gradual. It is especially characteristic to the pottery of the 13th-14th centuries when most of discrepancies in pottery are influenced mainly by the individual peculiarities of every potter but not by the chronological differences. Crushed granite is typically used as a temper, the intensity of turning varies from the subtle surface smoothing to the partial forming of vessel. However... [to full text]

This thesis is a study of pottery in the museum world. Throughout the study, questions along the lines of how, why and what we exhibit are brought up and answered. The study is done through observations and interviews with seven different museums, four of which are located in Sweden and three in Italy. The author has also used museological literature and theories in order to strengthen the essay and show that the issues brought up in the observations are known since before in the field, but still exist in the museums today.The exhibiting of pottery comes with several issues, such as overcrowding of displays, requirements of pre-knowledge from the visitors, aesthetical problems with broken, coarse or fine pottery and epistemological prob-lems. Epistemology is a subject that seems to be partly ignored in the observed museums, despite it being general knowledge that fewer visitors will read the text the longer it is. Other epistemological problems that are brought up are the issues of text placement, vocabulary and actual mediated information. These problems are brought up throughout the essay and explained, with a smaller section that discusses possible improvements to them, which have been brought up by researchers in the field.In interviews with curators of the museums, thoughts about what the visitors see and understand compared to what the museums want them the see are presented. Also their views on the possibilities of interaction with pottery as a mediator and whether they focus primarily on aesthetics or learning in the exhibitions are shown. This essay is not meant to be a decider between what is right or wrong concerning the exhibiting of pottery, but could be used as a stepping-stone towards such studies. This is a two years master’s thesis in Archive, Library and Museum studies. / Den här uppsatsen är en studie av krukor i museivärlden. Genomgående i studien kommer frågor som hur, varför och vad vi ställer ut tas upp och besvaras. Studien har gjorts genom observationer och intervjuer med sju olika museer, fyra belägna i Sverige och tre i Italien. Författaren har också använt sig av museologisk litteratur och museologiska teorier för att stärka uppsatsen och visa att de problem som tagits upp i observationerna är kända sedan tidigare inom fältet, men trots det existerar i museer idag.Utställande av krukor medför flera problem, såsom överfulla montrar, krav på förkunskaper hos besökarna, estetiska problem med trasig, bruks- eller finkeramik samt epistemologiska problem. Epistemologi verkar vara ett ämne som delvis ignoreras i de observerade museerna, trots att det är allmänt känt att färre besökare kommer att läsa texten ju längre den är. Andra epistemologiska problem som behandlas är sådana som textplacering, vokabu-lär och faktiskt förmedlad kunskap. Dessa problem tas upp och förklaras i uppsatsen med en mindre sektion som diskuterar möjliga förbättringar av dem, baserat på idéer från forskare inom fältet.I intervjuerna med curatorer från museerna presenteras deras tankar om vad besökarna ser och förstår jäm-fört med vad museerna vill att de ska förstå. Också deras syn på möjligheterna av interaktion genom krukor och huruvida de fokuserar främst på det estetiska eller pedagogiska i utställningarna visas. Den här uppsatsen är inte menad att skilja mellan rätt och fel vid utställandet av krukor, men kan användas som ett avstamp mot sådana studier. Det här är en två-årig masteruppsats i Arkiv-, Biblioteks- och Museivetenskap.

The phenomenal growth rate for the use of engineering ceramics is attributed to successful scientific responses to industrial demand. These materials are replacing metal and its alloys in diverse applications from cutting tools and heat engine components to integrated circuits. Joining technology plays a vital role in this changing and evolving technology as success and failure comes with breaking new barriers. It is important to improve existing techniques and to develop new techniques that reliably join simple shape components to form complex assemblies or join dissimilar materials such as metal to ceramic. Joining of ceramics is not simple due to their high chemical stability and low coefficient of thermal expansion (CTE). Joining between metal and ceramic is usually carried out at elevated temperatures and upon cooling thermal residual stresses are induced that lead to joint failure or poor strength. Most metal-ceramic joints cannot be used over 500°C primarily due to the low melting temperature of the interlayer. This investigation was concerned with the successful joining for higher temperature applications (above 500°C) of two dissimilar high temperature oxidation and corrosion resistant materials, Fecralloy and silicon nitride. The primary focus was on the effects of process conditions upon the microstructure and mechanical properties of the joint and to also study/identify the joining mechanism. Two novel techniques were employed to join successfully the metal to ceramic. The first was by use of a thin Cu foil that did not remain after joining. Joining occurs by a process that results in partial melting of the Fecralloy interface, where Fe, Cr, Al and Cu reactively infiltrate into the silicon nitride. This liquid mixture causes partial dissolution of the silicon nitride interface, where Si and N diffuse into the Fecralloy. A thin reaction product layer was formed at the silicon nitride interface and our results suggested that this was AIN. The free surface Si and porosity of the silicon nitride along with the eutectic temperatures above 1100°C are all vital for this joining process. The highest average shear strength of a Fecralloy-silicon nitride joint produced by the method was 67.5 MPa. The second route was that of a powder metallurgy one, where cold pressed Ni-Al (1:1 molar) compacts were used to join successfully the Fecralloy to silicon nitride. The formation of NiAl from its constituents is highly exothermic and this is initiated between 500-650°C. The high temperature reached causes partial melting of the Fecralloy interface and dissolution/reactive wetting at the silicon nitride interface. Mostly Fe infiltrates the NiAl improving room temperature ductility, fracture toughness and yield strength. Molten Al from the interlayer reacts and wets the silicon nitride interface with small amount of infiltration and no reaction product forming. The reaction synthesis of NiAl was studied using DTA and TGA, where the effects of Ni particle size and heating rate were investigated. This joining process is highly dependant upon process conditions, the most important of which are applied pressure, heating rate and Ni/A1 particle size. The highest average shear strength attained was 94.30 MPa and this is attributed to good interfacial bonding, high pressure, moderate process temperature and dwell time. The exothermic formation of the NiAl interlayer that is densified and monophase was paramount for this joining process. The Bansal-Doremus kinetic model for evaluating the kinetic parameters from non-isothermal DTA data was shown to be valid. The results obtained were identical to those by other authors who used a different model and approach.

Bone consists of collagen/hydroxyapatite (HA) composites in which poorly crystalline carbonated calcium phosphate is intercalated within the fibrillar structure. Normal bone mineral is a carbonated-apatite, but there are limited data on the effect of mineral containing carbonate on cell response. Although the exact biological role of silicate in bone formation is unclear, silicate has been identified at trace levels in immature bone and is believed to play a metabolic role in new bone formation. To mimic the inorganic and organic composition of bone we have developed a variety of bone graft substitutes. In the present body of research, we characterized the surface composition of human cortical and trabecular bone. When then characterized the surface compositions of the following potential bone substitutes: carbonated hydroxyapatite (CO₃²-HA), silicated hydroxyapatite (Si-HA), and collagen sponges mineralized with calcium phosphate using the polymer-induced liquid-precursor (PILP) process. In the latter substitutes, the PILP process leads to type I collagen fibrils infiltrated with an amorphous mineral precursor upon which crystallization leads to intrafibrillar HA closely mimicking physiological bone mineral. We then determined the osteoblast-like cell response to each bone substitute to characterize the substrate’s effect on osteoblast differentiation. The observations collectively indicate that cells are sensitive to the formatting of the mineral phase of a bone substitute and that this format can be altered to modulate cell behavior.