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A potential method for manufacturing antibacterial ceramics can be the incorporation of Ag+ ions into the surface of ceramic glaze via Ag+↔Na+ ion exchange. The ion‐exchange process is usually modulated by the concentration of AgNO3 in the ion‐exchange medium, which, in turn, affects the antibacterial activity. Therefore, the present study investigated the diffusion behavior of Ag+ ions into the glaze at different concentrations (2–10 wt%) of AgNO3 in the ion exchange AgNO3–NaNO3 medium and their release behavior from the ion‐exchanged glaze. The antibacterial activity of the Ag+ ion‐exchanged glaze was also evaluated. As AgNO3 concentration in AgNO3–NaNO3 molten salt increased from 2 to 10 wt%, the diffusion coefficient of Ag+ ions in the molten salt increased from 1.49 × 1021 to 3.84 × 1045 cm2 s−1, and its Nernst distribution coefficient increased from 0.65 to 4.13. This led to the increased incorporation of Ag+ ions in the glaze, which was beneficial for the ion‐exchanged glaze to release Ag+ ions, with the concentration increasing from 0.03 to 0.10 μg mL−1 cm−2 in 24 h, and maintain leaching of the Ag+ ions for a long time to exert long‐term antibacterial activity. [ABSTRACT FROM AUTHOR]

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A frit is a glassy ceramic composition that has been fused, quenched, and granulated. A single frit or a mixture of frits and ceramic materials forms a ceramic glaze. The purpose of this pre-fusion is to render any soluble and/or toxic components insoluble by rendering it inert in a glassy composition with silica and other added oxides. The ceramic glaze dispersed in water (ceramic slip) is deposited on a ceramic body and fired for waterproofing and aesthetic purposes. Multicomponent frits (zinc-potassium borosilicate system) with similar behavior to conventional ceramic frits for single-firing ceramic glazes ("monoporosa" glazes fired at 1080 °C) were prepared by Sol-Gel methods (monophasic and polyphasic gels) avoiding the pre-fusion and characterized as photocatalytic agents (showing high degradation activity on Orange II). The effect of doping with bandgap modifiers (V2O5, Sb2O5 and SnO2) and also with devitrification agents (ZrO2 to crystallize zircon, Al2O3 to anorthite, Mo2O3 to powellite and ZnO to gahnite ZnAl2O4) were analyzed. Highlights: Multicomponent frits (zinc-potassium borosilicate system) with similar behavior to conventional ceramic frits were prepared by Sol-Gel methods without pre-fusion. Zinc and potassium borosilicate-based glaze, modified with alumina and calcium, is considered the optimum for conventional applications, and shows a moderate photoactivity with a half-life period of 77 min. Doping with bandgap modifiers enhances the photoactivity; V2O5 or SnO2 show good photoactivity in the 5 w% sample (t1/2 = 55 and 58 min, respectively). Doping with devitrification agents (ZrO2 to crystallize zircon, Al2O3 to anorthite, Mo2O3 to powellite and ZnO to gahnite ZnAl2O4) shows that the photocatalytic activity is low, similar or lower than the SG4 zinc-potassium borosilicate parent glaze. [ABSTRACT FROM AUTHOR]

Silver and copper borate nanostructures were mechanistically synthesized for novel boron-containing antibacterial applications. Different concentration, temperature, time parameters were varied for obtaining hierarchical formulations. Metal borate nanostructures showed interesting crystalline and optical properties since temperature and concentration adjustments provided correlated shape and surface properties with around 300 nm size. Chemical analysis and crystallinity of both copper and silver formulations were conducted with X-ray diffraction and unveiled that especially temperatures ranging from 40 to 90 °C has a huge impact on the formation of nanostructures. X-ray photoelectron spectroscopy analysis comprehensively provided all atomic compositions especially about boron atom at 191–192 eV range. Additionally, energy-dispersive X-ray analysis with scanning electron microscope measurements revealed the morphological properties of the nanostructures and showed the purity of the obtained materials. Finally, metal borate-containing glazes were obtained on 1 × 1 cm samples for antibacterial tests against Gram-positive and Gram-negative microorganisms. [ABSTRACT FROM AUTHOR]

In this study, silver nanoparticles (Ag NPs) were successfully synthesized by using the green chemistry method, which is simple, environment friendly, and economical by using plant extract obtained from Abelmoschus esculentus. The synthesized Ag NPs were characterized using ultraviolet–visible (UV–Vis) spectroscopy, thermogravimetric analysis, transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray crystallography and X-ray photoelectron spectroscopy. The synthesized Ag NPs showed absorbance peaks at 432 nm in the UV–Vis spectroscopy. The mean particle size of Ag NPs was found to be 8.96 nm. The antimicrobial activity of Ag NPs was examined on Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), Bacillus subtilis (B. subtilis) and Methicillin-resistant Staphylococcus aureus. Besides, the antibacterial activity of Ag NPs was compared with commercially available antibiotics (Penicillin–streptomycin and Ampicillin–sulbactam). Ag NPs exhibited excellent antimicrobial activity against gram-positive and gram-negative bacteria. In addition, Ag NPs were used in ceramic glaze, and thus, an antibacterial ceramic glaze was developed. [ABSTRACT FROM AUTHOR]

Copyright of Journal of the Faculty of Letters / Trakya Üniversitesi Edebiyat Fakültesi Dergisi is the property of Trakya University, Faculty of Letters and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The advantages of microwave (MW) energy processing have been verified in the sintering of a ceramic frit at a pre‐industrial scale. The challenge of achieving high temperature using MW energy at such dimensions was overcome and a mix of natural raw materials was heated until its fluxing point. Changes in dielectric properties of the raw materials mix were also measured in situ with the increase in temperature, being in accordance to thermal processes of a conventional heating process. The properties of the resulting ceramic frit were compared with the same frit obtained by the conventional sintering method. Both frits showed similar thermal behavior regarding DTA‐TGA, heating microscopy and XRD (only glassy phase was present). A Raman study confirms the existence of the mentioned glass phase. The application of the frits as glazes were performed and their properties were studied. As a result, glazes with similar properties were obtained which confirms that the MW energy processed frit is suitable for its application as a ceramic glaze. Obtaining ceramic frit in a pre‐industrial scale by applying MW energy. Validation of frit as ceramic glaze. Comparison of time, energy and CO2 removal in standard and MW heating processes. From laboratory results, a sustainable industrial process is developed. [ABSTRACT FROM AUTHOR]

Copyright of HOLOS is the property of Instituto Federal do Rio Grande do norte - IFRN and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ceramica is the property of Associacao Brasileira de Ceramica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article discusses ceramic glazes for wall to be made using waste glass, Waste electronic and electronical equipment (WEEE). It also presents that ceramic wall tiles are porous products made from clay, sand and limestone and a thin coating of glaze can make it waterproof, chemically stable and easy to clean. It also suggests re-usability of materials like glass, plastic and metal could be used as secondary raw material.

Colour tonality in the ceramic industry is a very interesting phenomenon commonly occurring in every day production, especially in big batch production. Tonality relates not only to the final product but also to semiproducts (coloured bodies, angobes, glazes, serigraphic pasts or inks). A key factor in producing high-quality ceramic products is maintaining the production technological regime. The present work tries to answer the following question: how can the firing condition affect the formation of colour tonality at the surface of ceramic tiles? The investigations relate to one glaze composition that was prepared in various grain size distributions and which was coloured using two pigments, beige and dark brown. The preparation procedure for the coloured glaze differed in terms of mixing technique and mixing time. The glazed samples of floor tiles were fired according to three different firing curves, which differ from each other in terms of maximum temperature and dwell time. These differences are common in industry. [ABSTRACT FROM AUTHOR]

Background, Aims and Scope. The interest in recycling materials at the end of their life is growing in the industry in general. As regards the Wastes of Electrical and Electronic Equipment (WEEE), an appreciable increase of these materials has been noticed in the last decades, 117 103 tons of WEEE have been produced in Italy in 2002 according to Ecohitech [11 and the increase in this kind of waste is three times higher than that of the municipal waste according to the FISE ASSOAMBIENTE report [21. Within WEEE, End-of-Life Cathode Ray Tube (EOL CRT) glass, the main part of TV sets and PC monitors, is here analysed using both a technical approach to establish a possible reuse of the glass in a open- loop recycling field (ceramic industry) and a methodology (LCA) capable of providing environmental evaluations. Methods. The technological characterization was performed by chemical resistance tests (UNI EN ISO 10545–13), staining tests (UNI EN ISO 10545–14) with blue methylene and potassium permanganate (KMnO4), and surface abrasion tests (UNI EN ISO 10545–7). The LCA study was conducted using the SimaPro 5.0 software and Eco-Indicator 99 as an evaluation method. Results and Discussion. The good technical results, reached by using cleaned EOL CRT panel glass inside a ceramic glaze formulation instead of a commercial frit, are supported by the environmental impact evaluation, which shows a decrease of the overall potential damage (measured in Points) of 36% and, in particular, a reduction of 53% in `Human health', 31% in `Ecosystem quality' and 24% in Resources'. Conclusions. This study has demonstrated that this new, open- loop recycling strategy for the CRT glass significantly reduces the environmental impact of the ceramic glaze production process. In fact, in all damage categories examined in this study, there is a minor impact. An improvement is evident in the respiratory inorganics sub-category related to the lowering of dusts mainly and to a lesser amount with NOx and SOx in the climate change sub-category, due mainly to the reduction of CO2 emission correlated to the avoided combustion of the mixture which feeds melting furnaces in the frit production. Thus, the damage decrease in `Ecosystem quality' is prevalently due to the lower NOx emissions by the kilns in the frit production that is evident in the acidificationleutrophication sub-category. Finally, the significant saving in the ‘Resource’ category is principally linked to the fossil fuels sub-category, thanks to the niethane saving which stokes the melting furnaces. Perspectives. Furthermore, the decrease in CO2 emission (94.4%) evident in the climate change sub-category is a very important topic because it is in line with the Kyoto protocol (1997), where significant efforts have been exerted for the reduction of the green house gases emission, notably CO2. The CO2 emission is correlated to the combustion of the mixture which feeds melting kilns in the frit production, therefore the recycling of secondary raw materials, already in a glass state, can reduce the emissions of this gas. This reduction can be termed as environmental credit and it is an ex- ample of an allocation of environmental loads in a open-loop recycling, where waste from one industrial system are used as raw materials in another product system. [ABSTRACT FROM AUTHOR]

Gold and silver salt mixtures are incorporated in ceramic glazes for in situ development of mixtures of gold and silver nanoparticles (NPs) that subsequently allow for a wide spectrum of low metal loading color control within ceramic materials. Prior work has shown that gold NPs can be used to create vibrant, color-rich red pigments in high-temperature ceramic and glass applications, though the achievable diameter of the gold NP ultimately limits the available range of color. The current study significantly expands color control from traditional gold nanoparticle red through silver nanoparticle green via the alteration of gold-to-silver salt ratios incorporated in the glaze formulations prior to sintering. Nanoparticle-based coloring systems are tested in both oxidative and reductive firing atmospheres. While the oxidation environment is found to be prohibitive for silver NP stability, the reductive atmosphere is able to form and sustain mixtures of gold and silver NPs across a wide color spectrum. All glazes are analyzed via reflectance spectrometry for color performance and samples are characterized via TEM and EDS for composition and sizing trends. This study creates new groundwork for a color-controlled NP system based on noble metal ratio blends that are both nontoxic and achieved with radically lower metal pigment loading than traditional glazes. [ABSTRACT FROM AUTHOR]