Ceramics

Whether due to his insight or influence, Foucault’s mixture of cynicism, paranoia and obsession with power mirrors our current cultural zeitgeist. His thoughts resonate on both thin edges of the American political thought. On the left, consider feminist law scholar Catharine MacKinnon who stated that men incarcerated for rape thinks it is stupid because “They were put into jail for something very little different from what most men do most of the time and they call it sex. The only difference is they got caught. It may also be right.”  On the right, there are those who believe that including homosexuality as a personal choice would lead to an epidemic of sodomy. In speaking of homosexuality, Pat Buchanan sees even mere acceptance as wrong.  While these ideas are clearly on the lip of the American political bell curve, it is an arc plotted on a Foucauldien graph. The X-axis is knowledge and the right axis is power.

The chronology of the Late Bronze Age (second half of the 2nd millennium BC), a key period characterised by a flourishing development of urban civilisation, is well known in western Syria, especially on the coast at Ugarit. However, the Late Bronze Age chronology in inner Syria and in particular in the middle Orontes valley still needs to be clarified. Recent excavations and archaeological surveys conducted at the site of Qatna and its surroundings have revealed new challenging data inducing a review of the Late Bronze Age chronology. This paper presents preliminary results of my PhD research on new ceramic findings from the Late Bronze Age excavations carried out in different operations by the Syrian team at Qatna from 2005 to 2010. An innovative approach is suggested that will allow the revision of chronological issues by establishing a new baseline reference for the stratigraphic sequences from Qatna through the examination of ceramic material. This examination based on traditional pottery studies is enhanced by petrographic analyses of ceramic sherds from Qatna and is accompanied by a comparative study of other Late Bronze Age sites in the Orontes valley region.

Currently, no consensus exists regarding the best adhesion protocol for zirconia used in dentistry; this is important particularly for restorations where mechanical retention is deficient. This systematic review analyzed the adhesion potential of resin-based and glass-ionomer luting cements to zirconia and aimed to highlight the possible dominant factors affecting the bond strength results to this substrate. Original scientific papers on adhesion to zirconia published in the MEDLINE (PubMed) database between 01/01/1995 and 01/06/2011 were included in this systematic review. The following MeSH terms, search terms, and their combinations were used: "Dental bonding", "Zirconium", "Zirconia", "Y-TZP", "Y-TZP ceramic", "Materials Testing/methods", "Test", "Cement", and "Resin bonding". Two reviewers performed screening and data abstraction. Descriptive statistics were performed and the frequencies o...

Yixing the Queen of Teapots, 2008, double DVD with box & photos booklet.
Idea, synopsis and scenario : Patrice Valfré
Photo and images : Luce Bouéry & Jacques Dussart
Interview of the co-producers, Patrice Valfré and Luc Bouéry, published in
La Revue de la Céramique et du Verre, n ° 160, in May-June 2008
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Yixing la reine des Théières, double DVD avec coffret & livret photos
Idée, synopsys et scénario: Patrice Valfré
Interview des réalisateurs Patrice Valfré et Luc Bouéry, publié dans La Revue de la Céramique et du Verre, n°160, mai-juin 2008

This PhD thesis engenders new approaches to the understanding, appreciation, and experience of modern and contemporary ceramic art. It focusses on two recent outputs. The initial, Scorched Earth: 100 Years of Southern African Potteries (2016), a scholarly publication, and the latter, Post-colonialism? (2016/2017), a socially-engaged international exhibition, held at the Benyamini Contemporary Ceramics Centre in Tel Aviv, Israel. The moral philosophy ubuntu was proposed as a component of self-reflexive methodology for research and curatorial projects. The term cryrator was advanced as constituting an approach to curatorial praxis in conflict zones. These concepts make an original contribution to existing methodologies and research that historicise, de-westernise, and decolonise knowledge.

[By Christopher Lotis and Michel D. Lee; Foreword by P.M. Taylor. This full book is uploaded here while the Smithsonian website, where it was published online, is being revised.]

An important theme of this volume is the relationship between ceramics and cultural identity, especially as it relates to a particular family’s collection, and also to the broader study of the personal and social aspects of collecting. The book thus forms a contribution not only to the study of Korea’s material heritage but also to Korean-American or Asian-American studies, and to the
history of collecting. It will surely be of interest to art as well as social historians, and to all those who appreciate the aesthetic quality of Korea’s ceramic art.

The authors’ “behind-the-scenes” study of this private collection included the creation of an extensive research database about it, not only the ceramics included in this volume but also paintings, costumes, bronze works, and many other objects that could form the basis for subsequent studies. The collection includes some important twentieth-century ceramics that have not been included within this volume; these await study alongside other works by contemporary artists in this wide-ranging
collection. As the authors emphasize, the component of the Chang collection selected for publication here has been extensively tested using thermoluminescence testing. For this reason, these objects constitute an important “type collection” of tested pieces for this type of materials analysis, against which other ceramic works may be compared.

This book should therefore serve as an important reference for work on its topic, as a unique and well-illustrated introduction to this private collection and its significance; and hopefully also as a stimulus for other studies within this and related private collections.

[NOTE: 2 photos, available in the print edition (p. 12), have been extracted from this online book because the copyright holder disallows online publication of those photos.]

This book is the edited proceedings from the conference 'The Art of Stesichorus' held at St John's College, Oxford, on June 29–30 2012. Contributors include: Ewen Bowie (Oxford), Chris Carey (London), Patrick Finglass (Nottingham), Richard Hunter (Cambridge), Adrian Kelly (Oxford), Ian Rutherford (Reading), Gerson Schade (Berlin), Laura Swift (Open University), Martin West (Oxford).

Pelling, C., Classics for All 2015/08/11

Iroquoians become recognizable in the archaeological record of southern Ontario about AD 500, with the appearance of Princess Point sites and maize agriculture in the lower Grand River valley. AfterA.D. 1000, Iroquoians lived in longhouse villages situated in the interior, north ...

Àtrucc è una caraffa da tavola destinata al vino ed è, in sintesi, un tentativo di coesione tra artigianato e disegno industriale: un salto nella tradizione ceramica rustica pugliese per sottrarre alle generazioni passate un "trucco", ovvero un "segreto", indagarlo ed avanzare ipotesi morfologiche e strutturali capaci di dare vita ad un prodotto contestualizzabile alla nostra modernità.

The restoration of anterior teeth is a difficult task, even for an experienced operator. Currently there are many different ceramic systems that can be used to achieve highly esthetic results. These include metal-ceramics with porcelain margins, Dicor, In-Ceram, Cerestore, Hi-Ceram, IPS-Empress, Cerapearl, Optec, and CAD/CAM ceramics. While metal-ceramics have been used for more than four decades, the quest for a material that transmits and refracts light like a natural tooth has inspired research into all-ceramic restorations. The purpose of this paper is to briefly discuss the properties of each of the above-mentioned materials and clinically evaluate the optical behavior of: (1) metal-ceramic crowns with castings 2 mm short of the shoulder preparation and 360-degree porcelain margins; (2) In-Ceram Spinell restorations; and (3) IPS Empress restorations, and to compare these with metal-ceramic crowns with copings to the shoulder preparation and 180-degree porcelain margins. Light t...

of the bur. Additional abrasion mesial and distal to the center line of the base can further reduce the force needed to fracture the bracket in debonding (C). Once the fracture line has been created, use either a Weingart or a How plier to squeeze and fracture the tie wings (D). How pliers tend to produce better results than Weingart pliers because of the greater distance between the plier hinge and tips, which makes for a better fit between the internal surfaces of the tips and the external surfaces of the tie wings. In most cases, the two halves of the bracket will debond simultaneously. If one half stays on the tooth, it is easily removed by applying a rocking motion with the same plier. Ceramic fragments often remain on the enamel after debonding of monocrystalline brackets1 (E), requiring removal with the same high-speed diamond bur under water cooling. Any adhesive remnants should be removed by using a low-speed, sixor 12-blade tungsten carbide bur with a smooth, rounded tip. ...

The aim of this study was to assess in vitro the influence of the CO2 laser and of the type of ceramic bracket on the shear bond strength (SBS) to enamel. A total of 60 enamel test surfaces were obtained from bovine incisors and randomly assigned to two groups, according to the ceramic bracket used: Allure (A); Transcend (T). Each group was divided into 2 subgroups (n = 15): L, laser (10W, 3s); C, no laser, or control. Twenty-four hours after the bonding protocol using Transbond XT, SBS was tested at a crosshead speed of 0.5 mm/min in a universal testing machine. After debonding, the Adhesive Remnant Index (ARI) was evaluated at 10 x magnification and compared among the groups. Data were analyzed by one-way ANOVA, Tukey's, Mann-Whitney's and Kruskal-Wallis tests (α = 0.05). Mean SBS in MPa were: AL = 0.88 ± 0.84; AC = 12.22 ± 3.45; TL = 12.10 ± 5.11; TC = 17.71 ± 6.16. ARI analysis showed that 73% of the specimens presented the entire adhesive remaining on the tooth surfaces...

Streszczenie W pracy przedstawiono sposób otrzymywania i wyniki pomiarów wáaĞciwoĞci fizycznych ceramiki (Pb1-xLax)(Zr1-yTiy) O3, gdzie x= 0, 03 lub 0, 06, y= 0, 9 (PLZT) oraz (Pb1-xLax)[(Zr1-yTiy) 1-zSnz] O3, gdzie x= 0, 04, y= 0, 9, z= 0, 02, 0, 04, 0, 06, 0, 08 (PLZTS). Materiaáy te naleĪą do roztworów staáych tlenowooktaedrycznych o strukturze typu perowskitu. Badane materiaáy zostaáy wykonane przy uĪyciu klasycznej technologii ceramicznej z wykorzystaniem tlenków. Przedstawione zostaáy wyniki badaĔ ...

Cerium oxide (CeO2) has been prepared as a ceramic dielectric resonator by a conventional solid-state ceramic route. The sintered CeO2 has a high dielectric quality factor (Q×f), Q value of 10 000 at 6 GHz with a relative permittivity (ε′) of 23, and temperature coefficient of resonant frequency (τf of -53 ppm/°C. The Q value increases to 20 000 at 6 GHz when the CeO2 is doped with 1 mol% CaCO3. Higher levels of CaCO3 doping lowers the Q and ε′ values and simultaneously decreases τf. TiO2 doping decreases τf and slightly increases ε′, but deceases the Q value. The Q value of pure CeO2 increases to 105 000 at a frequency of 5.58 GHz when it is cooled to 30 K, whereas Q ≈ 85 000 at 5.48 GHz for 1-mol%-CaCO3-doped CeO2 at 30 K.

Al2O3-TiO2 systems with Ti:Al 0.1, 0.5 and 1.0 molar ratio obtained by the sol–gel method have been used as a platinum support. As a precursor of alumina gel, aluminum isopropoxide has been chosen. Titanium tert-butoxylate was applied to obtain titania gel and hexachloroplatinic acid was applied as a source of platinum. The systems have been characterized by the following methods: thermogravimetric analysis (TGA), Fourier transformation infrared spectroscopy (FTIR), X-ray powder diffraction (XRPD), low-temperature nitrogen adsorption–desorption isotherms (BET, BJH), temperature-programmed reduction with hydrogen (TPR-H2) and hydrogen chemisorption. Reactions of toluene to methylcyclohexane and selective o-chloronitrobenzene (o-CNB) to o-chloroaniline (o-CAN) hydrogenation were used as the tests of systems’ catalytic activity. The application of Al2O3-TiO2 as a support has enabled the obtaining of platinum catalysts showing high activities for hydrogenation of toluene and selective h...

In a 4-year period, 40 compact aluminum oxide ceramic implants fixed with titanium plates and screws were used: 24 for the correction of mandibular defects, 9 for temporomandibular joint replacement, and 7 for augmentation of facial contour. During the 1 to 4 years following the operations, it was not necessary to remove any aluminum oxide joint or implant used for contour correction. In 5 of the 24 cases of mandibular reconstruction, however, it was necessary to remove the ceramic. In 3 cases, this was due to recurrence of the tumor, and in 2 cases the cause was dermal necrosis.

The formation of solid solutions of the type [Ba(HOC2H4OH)4][Ti1−x Gex (OC2H4O)3] as Ba(Ti1−x /Gex )O3 precursors and the phase evolution during thermal decomposition of [Ba(HOC2H4OH)4][Ti0.9Ge0.1(OC2H4O)3] (1) are described herein. The 1,2-ethanediolato complex 1 decomposes above 589 °C to a mixture of BaTiO3 and BaGeO3. A heating rate controlled calcination procedure, up to 730 °C, leads to a nm-sized Ba(Ti0.9/Ge0.1)O3 powder (1a) with a specific surface area of S = 16.9 m2/g, whereas a constant heating rate calcination at 1,000 °C for 2 h yields a powder (1b) of S = 3.0 m2/g. The shrinkage and sintering behaviour of the resulting Ba(Ti0.9/Ge0.1)O3 powder compacts in comparison with nm-sized BaTiO3 powder compacts (2a) has been investigated. A two-step sintering procedure of nm-sized Ba(Ti0.9/Ge0.1)O3 compacts (1a) leads, below 900 °C, to ceramic bodies with a relative density of ≥90%. Furthermore, the cubic ⇆ tetragonal phase transition temperature has been detected by dilatometry, and the temperature dependence of the dielectric constant (relative permittivity) has also been measured.

Boron doped and undoped Poly(vinyl) alcohol/Zirconium-yttrium acetate (PVA/Zr-Y) nanofibers were prepared by electrospinning using PVA as a precursor. The effect of boron doping was investigated in terms of solution properties, morphological changes and thermal properties. The effect of boron doping on calcined yttria stabilized zirconia (YSZ) fibers were evaluated by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy analysis. XRD
analysis revealed varying amounts of monoclinic and tetragonal zirconia present in the undoped fibers calcined at 800oC. The average crystallite sizes of the undoped YSZ were increased from 9.28 to 22.79 nm with calcining temperature increasing from 250 to 800 °C. The crystallite size was enhanced with boron doping. The systematic evolution of morphological features in the spun and the processed fibers were employed by scanning electron microscopy.

The present paper deals with an experimental convective heat transfer investigation around a film-cooled, high-pressure gas turbine rotor blade mounted in a stationary, linear cascade arrangement. The measurements were performed in the von Karman Institute Isentropic Light Piston Compression Tube facility. The test blade was made of Macor glass ceramic and was instrumented with thin film gages. The coolant flow was ejected simultaneously through the leading edge (three rows of holes), the suction side (two rows of holes), and the pressure side (one row of holes). The effects of overall mass weight ratio, coolant to free-stream temperature ratio, and free-stream turbulence were successively investigated.

The purpose of this study was to evaluate the production feasibility of triaxial whiteware using sand from cast iron moulds as a raw material instead of silica, and recycled glass in place of feldspar. Formulations were prepared using sand, glass waste, and white-firing clay such that only 50% of the composition was virgin material (clay). The ceramic bodies were formed by pressing and fired at different temperatures (between 1100 and 1300 degrees C). Specimens were characterized in terms of green density prior to firing; and their flexural strength, linear shrinkage, and water absorption were measured after firing. The microstructure was determined by scanning electron microscopy. Possible environmental impacts of this recycling process were also evaluated, through solubility and leaching tests, according to Brazilian standards. Gaseous emissions during the firing process were also analysed. The results showed that it is possible to produce triaxial ceramics by using such alternati...