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[en] Optimized compositions of a four-color CMYK plus a green pigment have been prepared by the ceramic method: cobalt doping in Celsian (Ba0,9Co0,1)Al2Si2O8 (cyan), chromium in armalcolite (MgFe)(Cr0,2Ti2,8Fe)O10 (magenta), nickel in geikielite (Mg0,5Ni0,5)TiO3 (yellow), the perovskite CrNdO3 (green) and the same perovskite mineralized with alkaline earth fluorides (BaF2 and MgF2) (black). Both pigment powder and glazed sample in a conventional double firing frit (1050°C) have been characterized with respect to its colorimetric performance by the model CIEL*a*b*, its cooling capacity (as cool pigments) by the measurement of the solar reflection index SRI and its photocatalytic capacity by means of the OrangeII degradation test. The obtained results are compared with those obtained with commercial pigments of the CMY family of the zircon. The results indicate that the coloration of the powders and the enamelled samples is more intense, with L* values lower than the zircon homologous pigments, whereas the obtained chroma with the pigments of the zircon is better (b* negative for cyan, a* positive for magenta and b* positive for yellow). Regarding its cooling capacity, the results indicate high SRI values for all samples. In the case of Celsian SRI is higher than for vanadium-zircon, the green of perovskite slightly exceeds the eskolaite Cr2O3 value that is taken as reference. In the case of the black perovskite, very low SRI values are measured (SRI=0 in the case of powder) and associated with high middle-infrared emissivity values, making it interesting as a pigment for absorbent substrates in solar collectors. The photocatalytic capacity over OrangeII indicates half-life values around 55-70minutes, lower than those measured in zircons (110-190minutes).
[es]Se han preparado por el método cerámico composiciones optimizadas de una cuatricromía CMYK más un pigmento verde, basados en el dopado de cobalto en celsiana (Ba0,9Co0,1)Al2Si2O8 (cian), de cromo en armalcolita (MgFe)(Cr0,2Ti2,8Fe)O10 (magenta), de níquel en geikielita (Mg0,5Ni0,5)TiO3 (amarillo), la perovskita CrNdO3 (verde) y la misma perovskita mineralizada con fluoruros alcalinotérreos (BaF2 y MgF2) (negro). Los pigmentos en polvo y los vidriados obtenidos con una frita convencional de bicocción (1.050°C) se han caracterizado respecto de su rendimiento colorimétrico mediante el modelo CIEL*a*b*; su capacidad refrigerante (como cool pigment), mediante la medida del índice de reflexión solar SRI, y su capacidad fotocatalítica, mediante el test de degradación de NaranjaII. Los resultados obtenidos se comparan con los obtenidos con pigmentos comerciales de la familia CMY del circón tomados como referencia. Los resultados indican una coloración intensa de los polvos y de las plaquetas vidriadas con valores L* inferiores a los pigmentos homólogos del circón, en cambio el chroma obtenido con los pigmentos del circón es superior (b* negativo para el cian, a* positivo para el magenta o b* positivo para el amarillo). Respecto a su capacidad refrigerante, los resultados indican valores SRI altos y superiores en el caso de la celsiana al del vanadio-circón, el verde supera ligeramente a la eskolaita Cr2O3, que se ha tomado como referencia, y en el caso de la perovskita negra sus valores SRI muy bajos (SRI=0 en el caso del polvo) y asociados a altos valores de emisividad en el infrarrojo medio la hacen interesante como pigmento para sustratos absorbentes en colectores solares. La capacidad fotocatalítica sobre NaranjaII indica valores de periodo de semivida en torno a 55-70min, inferiores a los medidos en los circones de referencia (110-190min).
[en] Digital Decoration Systems, SL (DIGIT-S) with Unicer, SL, has implemented a system to improve and optimize the process of decorating by inkjet printing for ceramic industry. It provides a comprehensive solution, KROME Ceramics, to improve the cost effectiveness of product and process through the implementation of a working system based on the control of digital decoration process and the synchronization of all elements that make up the decorative modules, including the creation of a work flow, management of files that are generated during the process, a correct color management system, and of course, optimizing and evaluating ink jet inks integrating all elements involved: Lighting, Computer, Software, Monitor, Plotter, Paper, Ink, Ink jet, Body's, Enamels and Oven. (Author)
[en] This report is one of four reports written to provide background information regarding immobilization technologies remaining under consideration for supplemental immobilization of Hanford's low-activity waste. This paper provides the reader a general understanding of joule-heated ceramic lined melters and their application to Hanford's low-activity waste.
[en] Silica aerogel and hybrid silica aerogel/pseudo wollastonite materials were synthesized by controlled hydrolysis of tetraethoxysilane (TEOS) using also methanol (MeOH) and pseudo wollastonite particles. The gels obtained were dried using a novel process based on an ambient pressure drying. Hexane and hexamethyl-disilazane (HMDZ) were the solvents used to chemically modify the surface. In order to assess bioactivity, aerogels, without and with pseudowollastonite particles, were immersed in simulated body fluid (SBF) for 7 and 14 days. The hybrid silica aerogel/pseudo wollastonite showed a higher bioactivity than that observed for the single silica aerogel. However, as in both cases a lower bioactivity was observed, a biomimetic method was also used to improve it. In this particular method, samples of both materials were immersed in SBF for 7 days followed by their immersion in a more concentrated solution (1.5 SBF) for 14 days. A thick and homogeneous bonelike apatite layer was formed on the biomimetically treated materials. Thus, bioactivity was successfully improved even on the aerogel with no pseudowollastonite particles. As expected, the hybrid silica aerogel/pseudowollastonite particles showed a higher bioactivity. (Author)
[en] The use and indiscriminate massive consumption of natural resources, degradation of environmental assets, and the damage that pollution causes to individuals and businesses, pose critical problems for society of XXI century. To paraphrase Ronald Coase, Economics Nobel Award in 1991, the deficiency of a system of property rights and application of some environmental goods carries a suboptimal use thereof. Therefore, in recent years there is a strong emphasis on environmental preservation and consequently many are joining efforts to make our planet continues to deteriorate due to the action of humans. The objective of this project is based on the analysis and development of organic mediums for ceramic decoration in keeping with the preservation of the environment. (Author) 11 refs.
[en] In this work has been studied the influence of the milling process of two ceramic frits used in the ceramic tile industry. Both glass frits were of similar chemical composition changing SiO2 by 5% of B2O3 and both of them were water or dry milled. Glass frit surfaces were characterized by FT-IR, Karl-Fischer (K-F) titration and Inverse Gas Chromatography at Infinite Dilution (IGC-ID). By K-F titration it was observed that water milled frits presented 28 and 26 OH groups for 100 A2 if they do not contain or contain boron, respectively. These surface changes are also observed by IGC-ID. Thus, the glass frit without boron and dry milled presented the highest dispersive surface energy (44 mJ.m-2) and the less acidic constant (0.13 kJ.mol-1). Both glass frits are amphoteric with acidic and base surface active sites, and that frit without boron presents the higher basicity. Milling process influences in the acid-base surface characteristics of both frits by increasing the basicity for the one without boron and increasing for the other one. This has been assigned to the different location of hydroxyl groups where the higher interaction is the one that does not contain boron and dry milled as K-F results. (Author)
[en] This article is to provide a new ceramic materials in which, with a control of their processing and thus their microstructural properties, you can get ceramic approaching ever closer to a metal, both in its structural behavior at low as at high temperatures. (Author) 30 refs.
[en] A cost-effective micro-manufacturing process to accurately build 3D microstructures for their prospective use in the fabrication of Solid Oxide Fuel Cells components has been tested. The 3D printing method, based on the stereo lithography, allows solidifying layer by layer a dispersion of ceramic material in a liquid photosensitive organic monomer. A simple projector, a computer-controlled z-stage and a few PowerPoint slides may be used for the fabrication of a wide range of complex 3D microstructures in few minutes. In this work, 3D ceramic microstructures based on the yttria-stabilized zirconia (YSZ) were successfully fabricated. The micro structured ceramic components produced were stable after sintering at 1400 degree centigrade for 4 h. Impedance measurements show that the fabrication process does not have any detrimental effect on the electrical properties of the structured material. (Author)
[en] Research in biomaterials and nano structures is inspired by the search of a common goal, that is, to remedy the pain, disease, and deterioration of our bodies. Manufacture of spare parts for the human body, both by traditional methods and using tissue engineering and cell therapy, is a major challenge in this research field. Additionally, the design of nanoparticles for drug delivery to direct a highly toxic drug dosage directly to tumors minimizing the effect to healthy cells and ensuring the death of tumor cells without affecting healthy tissues,is also a great challenge nowadays. The incessant progress in the preparation of nano systems with applications in the medical field in the last few years have led to new challenges in the design of smart materials able to meet clinical requirements. (Author)
[en] The evaluation of the colour of so-called metallized glazes is an important problem, especially since there is no clear definition for this type of material. The study shows that a spectrophotometer is not sufficient for evaluating the colour of these glazes, whereas a goniospectrophotometer with four angles of viewing enables a set of data to be obtained that more closely describe glaze appearance. However, the description of the colour component of glaze appearance using twelve chromatic coordinates is difficult to handle. For that reason, an index is proposed, similar to the whiteness or yellowness indices, for the evaluation of metallized appearance. This index is calculated from the goniospectrophotometer data, and has allowed metallized glazes to be differentiated from non-metallized glazes, in the set of samples used in this study. (Author) 5 refs.