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1.
Odovtos (En línea) ; 25(3): 67-81, Sep.-Dec. 2023. graf
Artigo em Inglês | LILACS, SaludCR | ID: biblio-1529070

RESUMO

Abstract To compare the physicochemical composition of 4 MTAs commercially available in Latin America. ProRoot MTA (Dentsply, USA), MTA Angelus (Angelus, Brazil), MTA Flow (Ultradent, USA), and MTA Viarden (Viarden, Mexico) were physically and chemically compared. Scanning electron microscopy (SEM) images were obtained from the MTA powder and the prepared presentations. Energy Dispersive X-Ray Spectroscopy (EDS) analyses were performed by triplicate, to calculate the mass proportion of calcium (Ca), silicon (Si), the Ca/Si proportion among the 4 brands. Thermogravimetric analyses (TGA) were conducted (50ºC-1000ºC), and mass loss and inflection points were calculated for each material. Statistical differences for Ca and Si content were determined by ANOVA (p<0.05). SEM images showed evident differences in the appearance of both the powder and the prepared MTAs among brands. Angelus MTA showed cubic prisms not observed in the other 3 brands. ProRoot MTA and MTA Flow showed similar homogeneous structures. MTA Viarden was the less homogeneous, with random structures (>15um). When comparing the mass proportions of Ca and Si between the 4 powder samples, MTA Viarden showed a significantly lower proportions of both elements when compared with the other brands (p<0.005). TGA análisis showed a similar behavior for ProRoot MTA, MTA Angelus and MTA Flow, with less than 2% mass loss when the 1000C temperature was reached. MTA Viarden showed a mass loss of 9,94% before the 700C, indicating the presence of different content sensible to temperature degradation. The analyzed MTAs demonstrated to vary significantly in their chemical composition and physical characteristics. Clinicians must be aware of the differences between different brands of a same material, and future research should focus on the clinical implications of these differences.


Resumen Comparar la composición fisicoquímica de 4 MTA disponibles comercialmente en América Latina. Se compararon física y químicamente ProRoot MTA (Dentsply, EE. UU.), MTA Angelus (Angelus, Brasil), MTA Flow (Ultradent, EE. UU.) y MTA Viarden (Viarden, México). Se obtuvieron imágenes de microscopía electrónica de barrido (SEM) del polvo de MTA y de las presentaciones preparadas. Los análisis de espectroscopía de dispersión de energía de rayos X (EDS) se realizaron por triplicado para calcular la proporción de masa de calcio (Ca), silicio (Si), la proporción Ca/Si entre las 4 marcas. Se realizaron análisis termogravimétricos (TGA) (50ºC-1000ºC), y se calcularon las pérdidas de masa y los puntos de inflexión para cada material. Las diferencias estadísticas para el contenido de Ca y Si se determinaron mediante ANOVA (p<0,05). Los análisis SEM mostraron diferencias evidentes en la apariencia tanto del polvo como las preparaciones de los MTA, entre las diferentes marcas. MTA Angelus mostró prismas cúbicos no observados en las otras 3 marcas. ProRoot MTA y MTA Flow mostraron estructuras homogéneas similares. MTA Viarden fue el menos homogéneo, con estructuras aleatorias (>15um). Al comparar las proporciones de masa de Ca y Si entre las 4 muestras de polvo, MTA Viarden mostró proporciones significativamente más bajas de ambos elementos en comparación con las otras marcas (p<0,005). El análisis TGA mostró un comportamiento similar para ProRoot MTA, MTA Angelus y MTA Flow, con menos del 2 % de pérdida de masa al alcanzar los 1000 °C de temperatura. El MTA Viarden mostró una pérdida de masa de 9,94% antes de los 700 °C, indicando la presencia de diferentes contenidos sensibles a la degradación por temperatura. Los MTA analizados demostraron diferencias significativas en su composición química y características físicas. Los clínicos deben ser conscientes de las diferencias entre las diferentes marcas de un mismo material, y futuras investigaciones deben enfocarse en las implicaciones clínicas de estas diferencias.


Assuntos
Microscopia Eletrônica de Varredura , Cerâmica/análise , Endodontia , Materiais Biocompatíveis
2.
Acta cir. bras ; 38: e380023, 2023. tab, graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1419864

RESUMO

Purpose: Low-intensity pulsed ultrasound (LIPUS) has been used to stimulate the healing of the fresh fracture, delayed union, and non-union in both animal and clinical studies. Besides, biphasic calcium phosphate ceramic (BCP) is a promising biomaterial for bone repair as it shows favorable biocompatibility, osteoinduction, and osteoconduction. However, scarcity is known about the combined effect of LIPUS and BCP on bone formation. Methods: The combined effect of LIPUS and BCP was studied in a beagle model. Twelve dogs were used. BCP granules without any additions were implanted into bilateral erector spinae muscles. One side is the BCP group, while the counterlateral side is LIPUS + BCP group. Histological and histomorphometric analyses, and quantitative real-time polymerase chain reaction were evaluated. Results: Compared with BCP alone, the LIPUS + BCP showed no advantages in early bone formation. Furthermore, the Notch signaling pathway-related mRNA has no significant difference between the two groups. Conclusions: The preliminary results showed that the BCP, which has intrinsic osteoinduction nature, was an effective and promising material. However, LIPUS has no enhanced effect in BCP induced ectopic bone formation. Furthermore, LIPUS has no effect on the Notch signaling pathway. Whether costly LIPUS could be used in combination with BCP should be a rethink.


Assuntos
Animais , Cães , Osteogênese/fisiologia , Terapia por Ultrassom/veterinária , Materiais Biocompatíveis , Cerâmica/análise
3.
ISA Trans ; 125: 400-414, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34217499

RESUMO

Automated defect detection is difficult to achieve in ceramic tile manufacturing today. Computer vision and machine learning based approaches are commonly utilised for this purpose. This paper considers the problem of defect detection in the textured ceramic tiles quality analysis. Instead of detecting defects on the finished tile, the biscuit tile is considered, a pressed, dried, decorated tile before its firing in the kiln. As it is an intermediary product during tile production, classifying them as defected or not before the firing can significantly reduce energy and material costs. To this end, in this paper we propose a new Fourier spectrum annuli feature extraction method. It is based on Fourier spectrum of the surface biscuit tile image and tested on real tile examples from the ceramic tile industry. According to the observed results, it outperforms several well-known methods for feature extraction on real-world tile datasets reaching an F1 score of 0.9236 and 0.8866 on the Black Random Stripes and Stripes Brown Light tile designs respectively.


Assuntos
Cerâmica , Indústrias , Cerâmica/análise , Análise de Fourier
4.
Molecules ; 26(14)2021 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-34299602

RESUMO

Potassium releasing bioactive glasses (BAGs) may offer improved relief for dentine hypersensitivity compared to conventional sodium containing BAGs by releasing K+ ions for nerve desensitization and occluding dentinal tubules to prevent fluid flow within dentinal tubules. Potassium oxide was substituted for sodium oxide on a molar basis in a fluoride containing BAG used in toothpastes for treating dentine hypersensitivity. The BAG powders were then immersed in an artificial saliva at pH 7 and tris buffer and the pH rise and ion release behavior were characterized by ICP-OES and ISE. The potassium and sodium containing BAGs were characterized by XRD, DSC, FTIR and NMR. Both BAGs presented amorphous diffraction patterns and the glass transition temperature of the potassium glass was higher than that of the sodium glass. The 31P MAS-NMR spectra indicated a peak at 2.7 ppm corresponding to apatite and a small peak at -103 ppm indicated crystallization to fluorapatite. Both BAGs dissolved and formed apatite at similar rates, although the dissolution of the potassium glass was slightly slower and it released less fluoride as a result of partial nanocrystallization to fluorapatite upon quenching. The potassium release from the potassium ions could potentially result in nerve deactivation when used in toothpastes.


Assuntos
Cerâmica/análise , Flúor/análise , Potássio/análise , Cremes Dentais/análise , Apatitas/análise , Materiais Biocompatíveis/análise , Dessensibilizantes Dentinários/análise , Fluoretos/análise , Humanos , Solubilidade
5.
Molecules ; 26(11)2021 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-34205105

RESUMO

The Late Neolithic palafitte site, Ustie na Drim, in the northern part of Lake Ohrid (North Macedonia), excavated in 1962, offered ceramic fragments of large, flat, elongated pans. These artifacts could be dated by relative chronology to roughly around 5200-5000 BC. According to their shape and technological traits, the ceramic pans were probably used for baking. The attached materials on the surface of studied pan fragments were sampled for consequent chemical and microscopical analyses (i.e., analyses of starch, phytoliths, and microscopic animal remains). An immunological method revealed the presence of pork proteins in samples. The presence of organic residues of animal origin was, moreover, confirmed by the detection of cholesterol using gas chromatography coupled to mass spectrometry. Analysis of detected microscopic botanical objects revealed starch grains of several plants (i.e., oak, cattail, and grasses). An interesting find was the hair of a beetle larva, which could be interpreted contextually as the khapra beetle, a pest of grain and flour. Based on our data, we suppose that the ceramic pans from Ustie na Drim were used for the preparation of meals containing meat from common livestock in combination with cereals and wild plants.


Assuntos
Cerâmica/análise , Alimentos/história , Extratos Vegetais/análise , Proteínas/análise , Animais , Arqueologia , Cerâmica/história , Culinária/história , Cromatografia Gasosa-Espectrometria de Massas , História Antiga , Extratos Vegetais/história , Proteínas/história , República da Macedônia do Norte , Suínos
6.
PLoS One ; 16(6): e0251407, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34077445

RESUMO

Neolithization, or the Holocene demographic expansion of farming populations, accounts for significant changes in human and animal biology, artifacts, languages, and cultures across the earth. For Island Southeast Asia, the orthodox Out of Taiwan hypothesis proposes that Neolithic expansion originated from Taiwan with populations moving south into Island Southeast Asia, while the Western Route Migration hypothesis suggests the earliest farming populations entered from Mainland Southeast Asia in the west. These hypotheses are also linked to competing explanations of the Austronesian expansion, one of the most significant population dispersals in the ancient world that influenced human and environmental diversity from Madagascar to Easter Island and Hawai'i to New Zealand. The fundamental archaeological test of the Out of Taiwan and Western Route Migration hypotheses is the geographic and chronological distribution of initial pottery assemblages, but these data have never been quantitatively analyzed. Using radiocarbon determinations from 20 archaeological sites, we present a Bayesian chronological analysis of initial pottery deposition in Island Southeast Asia and western Near Oceania. Both site-scale and island-scale Bayesian models were produced in Oxcal using radiocarbon determinations that are most confidently associated with selected target events. Our results indicate multi-directional Neolithic dispersal in Island Southeast Asia, with the earliest pottery contemporaneously deposited in western Borneo and the northern Philippines. This work supports emerging research that identifies separate processes of biological, linguistic, and material culture change in Island Southeast Asia.


Assuntos
Cerâmica/análise , Cerâmica/história , Datação Radiométrica/métodos , Sudeste Asiático , Cerâmica/química , História Antiga , Humanos , Filogenia
7.
Biomed Res Int ; 2021: 8875023, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33575352

RESUMO

BACKGROUND: Monolithic restorations made of translucent yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) have become popular over the past few decades. However, whether aging affects the color and translucency of monolithic translucent Y-TZP is unclear. OBJECTIVE: The aim of this systematic review and meta-analysis of in vitro studies was to evaluate the effects of aging on the color and translucency of monolithic translucent Y-TZP ceramics. MATERIALS AND METHODS: This systematic review/meta-analysis was reported according to the PRISMA statement and registered in the OSF registries (https://osf.io/5qjmu). Four databases including Medline via the PubMed, Embase, and Web of Science databases and the Cochrane Library were searched using no publication year and language limits. The last search was executed on November 20, 2020. In vitro studies comparing the translucency and/or color of monolithic translucent Y-TZP ceramics before and after simulated aging were selected. Meta-analyses were performed using Review Manager software (version 5.3, Cochrane Collaboration, Oxford, UK) with random-effects models at a significance level of 0.05. A risk-of-bias assessment was also performed for the included studies. RESULTS: Of the 188 potentially relevant studies, 13 were included in the systematic review. The hydrothermal aging duration ranged from 1 to 100 h at relatively similar temperatures (~134°C). In the general meta-analyses, the aged Y-TZP ceramics exhibited similar translucency parameter (TP), L∗, and b∗ values compared with the nonaged controls (P = .73, P = .49, and P = .62, respectively). Moreover, there was a significant difference between the aged and nonaged Y-TZP ceramics in the a∗ value (P = .03; MD = -0.26; 95% CI = -0.51 to - 0.02), favoring the nonaged Y-TZP ceramics. The subgroup analyses showed that the duration of aging contributed to changes in the translucency and color of the Y-TZP ceramics. CONCLUSIONS: The optical properties of monolithic translucent Y-TZP ceramics were stable after hydrothermal aging at 134°C and 0.2 MPa for ≤20 h. Moreover, clinically unacceptable changes in the translucency and color of monolithic translucent Y-TZP ceramics were found after hydrothermal aging for >20 h.


Assuntos
Cerâmica , Ítrio , Zircônio , Cerâmica/análise , Cerâmica/química , Cor , Teste de Materiais , Propriedades de Superfície , Temperatura , Fatores de Tempo , Ítrio/análise , Ítrio/química , Zircônio/análise , Zircônio/química
8.
Sci Rep ; 11(1): 1590, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33452410

RESUMO

A particular type of miniature ceramic vessel locally known as "veneneras" is occasionally found during archaeological excavations in the Maya Area. To date, only one study of a collection of such containers successfully identified organic residues through coupled chromatography-mass spectrometry methods. That study identified traces of nicotine likely associated with tobacco. Here we present a more complete picture by analyzing a suite of possible complementary ingredients in tobacco mixtures across a collection of 14 miniature vessels. The collection includes four different vessel forms and allows for the comparison of specimens which had previously formed part of museum exhibitions with recently excavated, untreated containers. Archaeological samples were compared with fresh as well as cured reference materials from two different species of tobacco (Nicotiana tabacum and N. rustica). In addition, we sampled six more plants which are linked to mind-altering practices through Mesoamerican ethnohistoric or ethnographic records. Analyses were conducted using UPLC-MS metabolomics-based analytical techniques, which significantly expand the possible detection of chemical compounds compared to previous biomarker-focused studies. Results include the detection of more than 9000 residual chemical features. We trace, for the first time, the presence of Mexican marigold (Tagetes lucida) in presumptive polydrug mixtures.


Assuntos
Cerâmica/análise , Metabolômica/métodos , Uso de Tabaco/história , Arqueologia , Cromatografia Líquida de Alta Pressão , História Antiga , Humanos , México , Análise de Componente Principal , Espectrometria de Massas em Tandem
9.
Arq. odontol ; 57: 229-235, jan.-dez. 2021. ilus, tab
Artigo em Português | LILACS, BBO - Odontologia | ID: biblio-1348096

RESUMO

Objetivo: É mérito deste estudo avaliar a pigmentação de cerâmicas odontológicassubmetidas a diferentes tratamentos de superfície e imersasem soluções corantes.Métodos: Foram confeccionadas 60 amostras de cerâmica, divididas em seis grupos. Os grupos G1, G2 e G3 receberam aplicação prévia de glaze, enquanto G4, G5 e G6 foram submetidos a desgastes e polimento. Os grupos foram mantidos em água destilada, açaí e café por um período de 30 dias. Foram realizadas fotografias digitais, seguidas da mensuração de cor da superfície com o programa mColorMeter, com base no sistema CIELab, antes da imersão, após 15 e 30 dias. Para avaliação quantitativa da variação de cor foi utilizada fórmula de ∆E, onde foram obtidos média e desvio padrão de cada grupo. Os dados foram submetidos à análise estatística ANOVA de dois fatores. Resultados: Após a realização da análise estatística, foram estabelecidos as médias e desvios-padrão para variância de cor (∆E) e foi constatado que não houve resultado estatisticamente significativo, em que p ≤ 0,05, para pigmentação em nenhum dos grupos de cerâmicas. Conclusão: Nesse contexto, infere-se que as substâncias café e açaí não promoveram alterações de cor significativas, bem como o glaze e o polimento mostraram-se igualmente eficientes na manutenção da estabilidade de cor das cerâmicas.


Aim: The present study sought to evaluate the pigmentation of dental ceramics submitted to different surface treatments and immersed in staining solutions. Methods: Sixty ceramic samples were manufactured and divided into six groups. Groups G1, G2, and G3 received a prior glaze application, while groups G4, G5, and G6 were submitted to wear and polishing. The groups were maintained in distilled water, açaí, and coffee for a period of 30 days. Digital photographs were taken, followed by color measurement of the surface with the mColorMeter program, based on system CIELab, before immersion, after 15 and 30 days. For quantitative evaluation of color variation, a formula from ∆E was used, where mean and standard deviation of each group were obtained. The data were submitted to ANOVA statistical analysis of two factors. Result: After the statistical analysis, the means and standard deviations for color variance (∆E) were established, and it was found that there were no statistically significant results, with p ≤ 0.05, for pigmentation in any of the groups of ceramics. Conclusion: Therefore, it can be inferred that coffee and açaí substances did not promote significant color changes. Glaze and polishing also proved equally efficient in maintaining the color stability of the ceramics.


Assuntos
Pigmentação , Cerâmica/análise , Cimentação , Prótese Dentária , Materiais Dentários/análise , Corantes/análise , Café/efeitos adversos , Euterpe/efeitos adversos
10.
PLoS One ; 15(7): e0235005, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32628680

RESUMO

Archaeology has yet to capitalise on the opportunities offered by bioarchaeological approaches to examine the impact of the 11th-century AD Norman Conquest of England. This study utilises an integrated multiproxy analytical approach to identify and explain changes and continuities in diet and foodways between the 10th and 13th centuries in the city of Oxford, UK. The integration of organic residue analysis of ceramics, carbon (δ13C) and nitrogen (δ15N) isotope analysis of human and animal bones, incremental analysis of δ13C and δ15N from human tooth dentine and palaeopathological analysis of human skeletal remains has revealed a broad pattern of increasing intensification and marketisation across various areas of economic practice, with a much lesser and more short-term impact of the Conquest on everyday lifestyles than is suggested by documentary sources. Nonetheless, isotope data indicate short-term periods of instability, particularly food insecurity, did impact individuals. Evidence of preferences for certain foodstuffs and cooking techniques documented among the elite classes were also observed among lower-status townspeople, suggesting that Anglo-Norman fashions could be adopted across the social spectrum. This study demonstrates the potential for future archaeological research to generate more nuanced understanding of the cultural impact of the Norman Conquest of England, while showcasing a method which can be used to elucidate the undocumented, everyday implications of other large-scale political events on non-elites.


Assuntos
Restos Mortais/química , Culinária/história , Dieta/história , Classe Social/história , Animais , Arqueologia/métodos , Osso e Ossos/química , Isótopos de Carbono/análise , Bovinos , Cerâmica/análise , Feminino , Cabras , História Medieval , Humanos , Masculino , Isótopos de Nitrogênio/análise , Ovinos , Suínos , Dente/química , Reino Unido
11.
Artigo em Inglês | MEDLINE | ID: mdl-32428414

RESUMO

Latest findings suggest that packaging and processing of food may be a contamination source of microplastics. In this study particle abrasion from five different salt mills with grinding burrs made of plastic and ceramic were investigated using micro-Raman (µ-Raman) spectroscopy. The mills were filled with a reference salt and an amount of 0.1 g was milled into a beaker, dissolved, filtered and the residues analysed via µ-Raman spectroscopy in different size classes, beginning with ≥ 1 µm. In the unground reference salt itself 423 ± 161 microplastic particles per 0.1 g were found, mainly consisting of polyethylene terephthalate (PET). These contents were not subtracted from the samples. One of the ceramic grinders also exclusively released PET-particles (527 ± 265 per 0.1 g).The other had compartments of polystyrene (PS) in the milling system and PS particles were found in the ground salt (201 ± 37 PET; 727 ± 226 PS/). Two of the plastic grinders had burrs made of polyoxymethylene (POM) and one with burrs of poly(methyl methacrylate) (PMMA). There were large amounts of 7628 ± 2655 and 5048 + 594 POM particles in 0.1 g salt in the two POM grinders as well as 265 ± 182 and 1546 ± 884 PET particles, respectively; salt from the PMMA grinder had 240 ± 41 PMMA particles/0.1 g and 1643 ± 1174 PET particles. The majority of the PET particles were smaller than 5 µm, whereas the POM, PS and PMMA particles had average sizes greater than 10 µm. In addition to possible microplastic contamination from salt itself, salt mills with grinding burrs made of plastic can emit microplastic particles in large amounts, especially if the burrs are made of POM. Other particles may, however, also be emitted from the grinders, e.g. ceramic particles in a similar size class, leading to the question whether and which kind of particles may be of toxicological concern for humans.


Assuntos
Cerâmica/análise , Plásticos/análise , Tamanho da Partícula , Controle de Qualidade , Sais/química , Análise Espectral Raman
12.
PLoS One ; 15(5): e0232906, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32459797

RESUMO

Mediterranean Early Iron Age chronology was mainly constructed by means of Greek Protogeometric and Geometric ceramic wares, which are widely used for chronological correlations with the Aegean. However, Greek Early Iron Age chronology that is exclusively based on historical evidence in the eastern Mediterranean as well as in the contexts of Greek colonisation in Sicily has not yet been tested by extended series of radiocarbon dates from well-dated stratified contexts in the Aegean. Due to the high chronological resolution that is only achievable by (metric-scale) stratigraphic 14C-age-depth modelling, the analysis of 21 14C-AMS dates on stratified animal bones from Sindos (northern Greece) shows results that immediately challenge the conventional Greek chronology. Based on pottery-style comparisons with other sites, the new dates for Sindos not only indicate a generally higher Aegean Early Iron Age chronology, but also imply the need for a revised understanding of the Greek periodisation system that will foreseeably have a major impact on our understanding of Greek and Mediterranean history.


Assuntos
Arqueologia/métodos , Cerâmica/história , Datação Radiométrica/métodos , Animais , Cerâmica/análise , Cronologia como Assunto , Fósseis/história , Grécia , História Antiga , Humanos , Sicília
13.
São José dos Campos; s.n; 2020. 105 p. il., graf., tab..
Tese em Português | BBO - Odontologia | ID: biblio-1150839

RESUMO

O presente estudo teve por objetivo avaliar o comportamento da camada de caracterização sobre zircônia de alta translucidez (YZHT, Vita YZ HT), cerâmica feldspática (FD/VMII, Vita Mark II) e silicato de lítio reforçado por zircônia (ZLS, Vita Suprinity) frente à simulação de desgaste fisiológico variando os antagonistas em YZHT, esteatita e cerâmica híbrida com polímero (Vita Enamic). Foram obtidos 120 discos (ø 12 mm, 1,2 mm de espessura) cerâmicos, sendo 30 de YZHT e FD, e 60 de ZLS, através de corte de blocos para CAD/CAM. As amostras de YZHT foram sinterizadas, e na sequência os grupos YZHT e FD receberam a camada de caracterização. A caracterização das amostras de ZLS foi realizada no mesmo ato da cristalização (ZLS1, etapa única) ou em queima posterior a cristalização (ZLS2, duas etapas). A caracterização foi realizada de acordo com as recomendações do fabricante e todas as amostras receberam aplicação de glaze e consequente queima. Os espécimes foram divididos em subgrupos (n=10) de acordo com os antagonistas: esteatita, cerâmica híbrida ou zircônia; em seguida, foram submetidos à simulação do desgaste fisiológico. Os parâmetros de rugosidade média (Ra) e largura média dos elementos do perfil de rugosidade (Rsm) foram analisados em diferentes momentos da simulação de desgaste fisiológico desde o início até o final da ciclagem. Após os 15.000 ciclos foram calculados a perda de massa dos discos cerâmicos e dos pistões antagonistas. Os resultados foram analisados estatisticamente por Anova 2 fatores e Tukey (p<0,05). Antes do desgaste, as cerâmicas não apresentaram diferenças para os parâmetros de rugosidade, Ra (p=0,3348), Rz (p=0,5590) e Rsm (p=0,5330). Os antagonistas não apresentaram diferenças para os parâmetros, Ra (p=0,0541) e Rsm (p=0,0613), enquanto que o parâmetro Rz (p=0,000) apresentou diferença, já que a esteatita (18,98 ± 2,98 µm) apresentou uma maior rugosidade média quando analisada a altura máxima do perfil quando comparado com os antagonistas em enamic (12,35 ± 0,91 µm) e zircônia (11,47 ± 0,89 µm). Após o desgaste, as cerâmicas continuaram sem apresentar diferenças estatísticas para os parâmetros de rugosidade, Ra (p=0,488), Rz (p=0,681) e Rsm (p=0,256). Os antagonistas não apresentaram diferença para o parâmetro Ra (p=0,124), porém, apresentaram diferença para o parâmetro Rz (p=0,000), já que a esteatita (57,98 ± 4,11 µm) apresentou uma maior média para tal parâmetro quando comparado com os antagonistas em enamic (44,86 ± 2,34 µm) e zircônia (37,81 ± 1,40 µm); e para o parâmetro Rsm (p=0,000), já que as médias da esteatita (502,72 ± 72,20 µm), enamic (385,67 ± 24,84 µm) e zircônia (268,94 ± 27,99 µm) apresentaram diferenças entre si. O tipo de cerâmica (p<0,0001) influenciou a perda de massa das amostras e a interação entre cerâmica e antagonista (p=0,0098), com isso influenciou a perda de massa dos pistões antagonistas. O grupo ZLS 2 apresentou a maior perda de massa entre os grupos testados. Todos os antagonistas testados apresentaram perda de massa semelhante contra o FD, enquanto a esteatita apresentou maior perda de massa quando testadas com amostras YHZT, ZLS 1 e ZLS 2. Todas as cerâmicas apresentaram rugosidade semelhante antes e após a simulação de desgaste. As amostras de cerâmicas apresentaram uma perda de massa semelhante. No entanto, a queima adicional da caracterização da cerâmica de silicato de lítio reforçado por zircônia favoreceu uma maior perda de massa, sem que houvesse alteração de sua resistência(AU)


The present study aimed to evaluate the behavior of the characterization layer on high translucency zirconia (YZHT, Vita YZ HT), feldspar ceramic (FD / VMII, Vita Mark II) and zirconia reinforced lithium silicate (ZLS, Vita Suprinity) compared to the simulation of physiological wear, varying the antagonists in YZHT, steatite and hybrid ceramic with polymer (Vita Enamic). 120 ceramic discs (ø 12 mm, 1.2 mm thick) were obtained, 30 from YZHT and FD, and 60 from ZLS, by cutting blocks for CAD / CAM. The YZHT samples were sintered, and in the sequence the groups YZHT and FD received the characterization layer. The characterization of the ZLS samples was carried out in the same act of crystallization (ZLS1, single step) or in burning after crystallization (ZLS2, two steps). The characterization was carried out according to the manufacturer's recommendations and all samples received application of glaze and consequent burning. The specimens were divided into subgroups (n = 10) according to the antagonists: steatite, hybrid ceramic or zirconia; then, they were submitted to the simulation of physiological wear. The parameters of average roughness (Ra) and average width of the elements of the roughness profile (Rsm) were analyzed at different moments of the simulation of physiological wear from the beginning to the end of the cycle. After 15,000 cycles, the mass loss of the ceramic discs and antagonistic pistons was calculated. The results were analyzed statistically by Anova 2 factors and Tukey (p <0.05). Before wear, the ceramics showed no differences for the roughness parameters, Ra (p = 0.3348), Rz (p = 0.5590) and Rsm (p = 0.5330). The antagonists showed no differences for the parameters, Ra (p = 0.0541) and Rsm (p = 0.0613), while the parameter Rz (p = 0.000) showed a difference, since steatite (18.98 ± 2) , 98 µm) presented a higher average roughness when the maximum profile height was analyzed when compared with the antagonists in enamic (12.35 ± 0.91 µm) and zirconia (11.47 ± 0.89 µm). After wear, the ceramics continued to show no statistical differences for the roughness parameters, Ra (p = 0.488), Rz (p = 0.681) and Rsm (p = 0.256). The antagonists showed no difference for the Ra parameter (p = 0.124), however, they showed a difference for the Rz parameter (p = 0.000), since steatite (57.98 ± 4.11 µm) showed a higher average for such parameter when compared with antagonists in enamic (44.86 ± 2.34 µm) and zirconia (37.81 ± 1.40 µm); and for the parameter Rsm (p = 0.000), since the averages of steatite (502.72 ± 72.20 µm), enamic (385.67 ± 24.84 µm) and zirconia (268.94 ± 27.99 µm ) showed differences between them. The type of ceramic (p <0.0001) influenced the loss of mass of the samples and the interaction between ceramic and antagonist (p = 0.0098), thereby influencing the loss of mass of the antagonist pistons. The ZLS 2 group showed the greatest loss of mass among the tested groups. All tested antagonists showed similar mass loss against FD, while steatite showed greater mass loss when tested with YHZT, ZLS 1 and ZLS 2 samples. All ceramics showed similar roughness before and after wear simulation. The ceramic samples showed a similar mass loss. However, the additional burning of the characterization of the zirconia-reinforced lithium silicate ceramic favored a greater loss of mass, without altering its strength(AU)


Assuntos
Cerâmica/análise , Desgaste de Restauração Dentária/efeitos adversos , Materiais Dentários/síntese química
14.
Anal Bioanal Chem ; 411(25): 6711-6722, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31372702

RESUMO

The detection of organic residues that remain absorbed into the pores of ceramic artifacts constitutes a source of information regarding their management. Taking into account the poor conservation state of the potteries and the low amount of the organic tracers together with the main drawbacks to get the relevant information concerning different aspects of past societies, the detection of organic biomarkers is still an analytical challenge. In this work, an improved analytical methodology to maximize the recovery of organic markers related to wine in archeological ceramics is presented. The developed method consists on the extraction of wine-related organic compounds including tartaric acid, malic acid, fumaric acid, succinic acid, citric acid, and syringic acid by means of ultrasonic probe-assisted extraction (UPAE) followed by a preconcentration step by mixed-mode strong anion exchange and reversed-phase solid-phase extraction (SPE) and a derivatization step prior to analysis by means of gas chromatography-mass spectrometry (GC-MS). Finally, the method was applied to real archeological ceramic fragments (two dolia), suspected to have been used to store wine, together with organic residues found inside two amphorae from Zaragoza (Spain). Graphical abstract.


Assuntos
Vinho/análise , Arqueologia , Cerâmica/análise , Cerâmica/história , Cromatografia Gasosa-Espectrometria de Massas/métodos , História Antiga , Extração Líquido-Líquido/métodos , Extração em Fase Sólida/métodos , Vinho/história
15.
Mar Pollut Bull ; 146: 653-666, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31426205

RESUMO

Seafloor litter has been studied both on the continental shelves (by trawling during 24 years) and in canyons (by ROV) of the French Mediterranean sea Water (FMW). On the continental shelf, mean densities range from 49.63 to 289.01 items/km2. The most abundant categories were plastic, glass/ceramics, metals and textiles. Trend analysis shows a significant increase in plastic quantities during the study period. Plastics accumulate at all depths, with heavier items being found in deeper areas, while the continental slope-break appears as a clean area. The spatial distribution of litter revealed the influence of geomorphologic factors, anthropic activities, shipping route, river inputs. All the canyons are affected by debris but coastal canyons (Ligurian Sea and Corsica) were more impacted than offshore canyons in the Gulf of Lion. The FMW appears to be highly polluted with regard to values found in other areas, but lower than those observed in the Eastern Mediterranean.


Assuntos
Metais/análise , Plásticos/análise , Têxteis/análise , Poluição da Água/análise , Cerâmica/análise , Monitoramento Ambiental/métodos , França , Mar Mediterrâneo , Rios , Navios , Análise Espaço-Temporal , Poluentes Químicos da Água/análise
16.
Environ Int ; 130: 104900, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31280051

RESUMO

In addition to the mitigation of carbon emissions through the reduction of building energy consumption, the prevention of fire spread in buildings is important an important task globally. Therefore, a growing interest towards building materials that can simultaneously contribute to energy savings and provide good flame-retardant performance in buildings exist. The flame-retardant performances of buildings can be improved through the use of inorganic building materials during construction. Meanwhile, among the different types of construction waste, more than 70% of ceramics can be recycled, which would reduce carbon emissions in the production process. Ceramics are inorganic and non-flammable, and can thus secure the flame-retardant performance of buildings. In this study, recycled ceramic-based inorganic insulation to secure the flame-retardant performance of a building are analyzed for their energy saving values. A case study building was modeled and the flame-retardant performance and building energy consumption were analyzed. Setting the thermal transmittance of the external wall according to the energy conservation design standards in South Korea, the tradeoff between model calculates annual energy consumption fire protection and minimization of material environmental impacts are discussed. As a result of simulation, when a wall constructed according to the energy conservation design standards of buildings, the building energy was saved by 18.6% and fire resistance performance was secured.


Assuntos
Cerâmica/análise , Materiais de Construção/análise , Retardadores de Chama/análise , Reciclagem , República da Coreia
17.
PLoS One ; 14(6): e0218001, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31216292

RESUMO

The rich Mediterranean imports found in Early Celtic princely sites (7th-5th cent. BC) in Southwestern Germany, Switzerland and Eastern France have long been the focus of archaeological and public interest. Consumption practices, particularly in the context of feasting, played a major role in Early Celtic life and imported ceramic vessels have consequently been interpreted as an attempt by the elite to imitate Mediterranean wine feasting. Here we present the first scientific study carried out to elucidate the use of Mediterranean imports in Early Celtic Central Europe and their local ceramic counterparts through organic residue analyses of 99 vessels from Vix-Mont Lassois, a key Early Celtic site. In the Mediterranean imports we identified imported plant oils and grape wine, and evidence points towards appropriation of these foreign vessels. Both Greek and local wares served for drinking grape wine and other plant-based fermented beverage(s). A wide variety of animal and plant by-products (e.g. fats, oils, waxes, resin) were also identified. Using an integrative approach, we show the importance of beehive products, millet and bacteriohopanoid beverage(s) in Early Celtic drinking practices. We highlight activities related to biomaterial transformation and show intra-site and status-related differences in consumption practices and/or beverage processing.


Assuntos
Cerâmica/análise , Grão Comestível/química , Comportamento Alimentar , Vinho , Animais , Arqueologia , Bebidas/análise , Europa (Continente) , França , Alemanha , Grécia , Humanos , Milhetes/química , Óleos de Plantas/análise , Suíça , Vitis/química , Ceras/química
18.
Environ Pollut ; 250: 717-727, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31035154

RESUMO

Mullite, a pure aluminosilicate (Al6Si2O13), is a rare natural rock component, known for centuries as a very resistant ceramic material. It is also a common waste product of high-temperature coal combustion that is emitted in quantity from coal-based power stations. The occurrence of mullite in two Sphagnum-dominated peatlands located near the Upper Silesia industrial region in southern Poland is described. For the first time, a complete record of mullite deposition in the peat profiles has been obtained by XRD analyses of ashed peat samples. The mullite distribution is compared with records of Hg, Pb and Cu. While mullite is supplied during high temperature processes only, Cu, Pb and Hg show more complex pattern of distribution. Both peat profiles contain elevated amounts of mullite in the time span between ca 1950-1990 with a maximum content in ca 1980. The first appearance (∼1900) of mullite is indicative of the beginning of energy production in coal-based power plants in the region. Mullite is proposed here as an indicator of industrialization in geological records. It is resistant to post-depositional processes, emitted globally, and restricted to large-scale industry.


Assuntos
Poluentes Atmosféricos/análise , Silicatos de Alumínio/análise , Cerâmica/análise , Cinza de Carvão/análise , Solo/química , Sphagnopsida/química , Monitoramento Ambiental , Indústrias , Polônia , Centrais Elétricas , Sphagnopsida/crescimento & desenvolvimento
19.
J Vis Exp ; (143)2019 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-30735164

RESUMO

An additive manufacturing technology is applied to obtain functionally graded ceramic parts. This technology, based on digital light processing/stereolithography, is developed within the scope of the CerAMfacturing European research project. A three-dimensional (3-D) hemi-maxillary bone-like structure is 3-D printed using custom aluminum oxide polymeric mixtures. The powders and mixtures are fully analyzed in terms of rheological behavior in order to ensure proper material handling during the printing process. The possibility to print functionally graded materials using the Admaflex technology is explained in this document. Field-emission scanning electron microscopy (FESEM) show that the sintered aluminum oxide ceramic part has a porosity lower than 1% and no remainder of the original layered structure is found after analysis.


Assuntos
Cerâmica/química , Polímeros/química , Impressão Tridimensional/instrumentação , Estereolitografia/instrumentação , Óxido de Alumínio/química , Cerâmica/análise , Porosidade
20.
Pesqui. bras. odontopediatria clín. integr ; 19(1): 3364, 01 Fevereiro 2019. ilus, tab
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-998008

RESUMO

Objective: To perform a clinical and histological evaluation, characterizing and proving the feasibility of the use of beta tricalcium phosphate (HA/ßTCP) bioceramics as a bone defect repair material, comparing it with autogenous bone and blood clot in terms of osteoinductive, conductive, and genic capacities. Material and Methods: The experiment was based on 3 critical defects in the mandible of 11 New Zealand rabbits. The defects were filled with HA/ßTCP bioceramics and autogenous bone, respectively, collected and ground during the development of defects and blood clots. The animals were euthanized after the 90-day experiment and samples were collected for histomorphological examination. To evaluate differences between the groups, a one-way analysis of variance (ANOVA) was performed with Tukey's post hoc test. An α value lower than 0.05 was considered statistically significant. Results: Microscopy revealed the presence of osteoblasts, osteoclasts, and osteocytes associated or not associated with the presence of mature or immature bone. All the studied materials presented bone neoformation in all cases, with the presence of mature and immature bone. Regarding the presence of HA/ßTCP bioceramic residual material, the same was found in 7 of 11 slides. Conclusion: HA/ßTCP bioceramics were shown to be a biocompatible bone substitute, with osteoinductive and osteoconductive characteristics, accelerating the process of new bone formation when compared with autogenous and blood clotted bone, thereby showing promise for bone defect repair with safety and efficacy.


Assuntos
Animais , Coelhos , Osso e Ossos , Implantes Dentários , Cerâmica/análise , Hidroxiapatitas , Nova Zelândia , Coelhos , Análise de Variância , Estatísticas não Paramétricas , Microscopia/instrumentação
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