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The European regulations encourage industries towards a green and circular economy in which “reuse” and “preparation for reuse” are keywords to reach an Innovating-to-Zero, ideal future at zero emission, zero waste and zero non-recyclable products. Directive 2008/98/EC sets the basic concepts and definitions related to waste management, such as the definition of waste, recycling and recovery. Waste and resources are positively defined as End-of-Waste material. The manufacturing of ceramic tiles is a traditional way for waste recovery with an increasing industrial interest and growing number of scientific papers.

Glazed ceramic tiles are characterized by a good chemical durability excepting in highly alkaline and acid environment. A continual use of cleaning agents with a basic or acid pH on ceramic flooring could give rise to a lowering of mechanical performances due to corrosion of crystalline phases more than the amorphous phase. In the present work, several glazed tile surfaces characterized by different microstructures (amorphous and partially crystallized) were considered. In order to better understand the mechanism responsible of the surface tiles ageing, the working surfaces, before and after chemical etching, were analysed from topografic, microstructural and mechanical point of view, Results showed that it is possible to correlate microstructural differences of ceramic surfaces before and after a chemical etching, with their physical-mechanical characteristics.

Product diversification, among which organic farming, is an important issue in modern aquaculture activities. Discriminating organic vs. conventional products is complex, but appearance may help in tracing different batches of produce. To test this fact, sea basses were fed a commercial or an organic diet, and fishes of each different group were photographed before and during the experiment. Body landmarks were digitized on each colour-calibrated (using the TPS-3D algorithm) image; on the basis of landmarks configuration, the RGB matrices were warped using a geometric morphometrics procedure. The calibrated colour matrix of each warped individual (195 × 135,225) was analyzed with a 50–50 MANOVA, followed by a partial least squares discriminant analysis. Finally, a cluster analysis on the diet/time groups was performed. Growth and changes in condition factor over time are not dependent on the rearing method. Colour (as represented by the pixel vector) does depend on time and on rearing method, based on the MANOVA method used. Standard length and condition factor were not good predictors of colour. The partial least square discriminant analysis was highly effective in detecting colour differences on the basis of the fish diet. The 9-group dendrogram showed that the wild sample and the organic fish cluster together. The head, darker in fishes raised conventionally, is the part showing the greatest difference; the longer the life spent under the 2 regimens, the stronger the differences. In conclusion, these preliminary results demonstrate that a colorimetric analysis is able to distinguish 2 batches of fishes fed different diets in different environmental conditions and – in the present instance – to certify the organically grown sea basses.

in the present work, scrap packaging glass coming from urban separted collection (post consumer waste) and industrial ceramic waste (pre-consumer waste) were used as secondary raw materials to prepare protoypes of ceramic tiles 100% green. Opportunely balances mixes of wastes are able ti sinergically interact during the thermal cycle, giving rise to innovative materials able to sinter about 200 C lower than a traditional ceramic tile mix, maintain good performances in terms of flexural strength, Young's modulus and Weibull's modulus

The possibility of recycling the Municipal Solid Wastes Incinerated (MSWI) bottom ash by its incorporation in ceramic tiles was investigated. The MSWI bottom ash was introduced both in untreated (previous deironization) and vitrified condition. The sintering of the different products was investigated by determining water absorption and linear shrinkage. To evaluate possible variations due to the presence of different amount of bottom ash, mineralogical and microstructural examinations by quantitative X-ray diffraction and scanning electron microscopy, were performed. While the untreated bottom ash, till an amount of 5 wt%, did not seem to affect the above characteristics of selected materials, the vitrified bottom ash, 5–10 wt%, as strong fluxing agent, promoted the sintering of porcelain stoneware. Leaching results allow to assert that the fired samples are not dangerous.

La sottrazione di rifiuti alla discarica e la loro valorizzazione economica sono attività che riguardano la tutela dell’Ambiente, la salute della popolazione e lo sviluppo industriale di un Paese, in particolare se povero di materie prime. Il Progetto LITCAR ha visto la partecipazione di vari laboratori presenti in Regione, con competenze specifiche e diversificate, che hanno contribuito alla realizzazione di un obiettivo condiviso: la valorizzazione dei rifiuti come materia prima secondaria per la realizzazione di prodotti commerciali a ridotto impatto ambientale, in linea con la filosofia europea della Politica Integrata di Prodotto (IPP). La suddivisione dei compiti, la condivisione di informazioni all’interno del gruppo di lavoro e la collaborazione di aziende che hanno creduto nel progetto, hanno consentito l’ottenimento di prodotti per l’edilizia ad elevate prestazioni tecnologiche.

SUMMARY. Chemical and mineralogical investigations show that the Bitburg meteorite is not a pallasite, but a group-IB iron meteorite. Like other members of this group it contains chondritic silicates. THE Bitburg meteorite is the largest meteorite discovered in Europe. It was brought to scientific attention by Gibbs (I814), an American army officer who had seen it in 18o5. He removed some material from the surface of the meteorite, and some time later an unsuccessful attempt was made to smelt the 1.6 t mass. Most of the smelted material was thrown into the local mill channel, but of the order of 15 kg are preserved in meteorite collections around the world; 55 kg in the Geologische Landesanstalt in Berlin were lost during the 1939-45 war (G. Hoppe, priv. comm.). Very little unsmelted material is known. Brauns (192o) carried out a thorough search for the unsmelted material, and reported that it could be found as individual specimens in the Tiibingen, Berlin, and Vienna collections, the aggregate mass being only about 34 g. He observed that some unsmelted portions were remarkably different from others, and it now appears that at least one of these (the Tiibingen specimen) has been smelted. Bitburg is classified as a pallasite in Hey (I 966). This classification goes back to Rose (1863) and is apparently based on the identification of the silicates as olivine. Brezina (1885) created a special Albacher group of brecciated pallasites in which he placed Bitburg (under the synonymous name of Albacher Miihle) and Brenham. During a survey of the Ni, Ga, Ge, and Ir contents of metal-rich meteorites, we noted that the composition of a smelted Bitburg sample (Smithsonian Institution specimen NMNH 445) was distinctly different from that of any known pallasite, and relatively similar to that of the group-IB iron meteorites With silicate inclusions Woodbine and Pitts (group-IB consists of all meteorites listed as I-An2 in Wasson (197o) that have Ge concentrations lower than 19o ppm). The data are shown in Table I, together with those for Woodbine and Pitts and for the two most similar pallasites, Brenham and Eagle Station. The analytical techniques used are the same as those reported in Wasson (I97o).

New analyses of rare earth and transition elements are summarized for 29 high-pressure metamafic rocks, which occur as lenses and layers in the Beigua serpentinite of the Ligurian Alps. Included are data for 2 metarodingites, 8 eclogites, 5 glaucophanic eclogites, 7 barroisitic amphibolites and 7 porphyroblastic greenschists. Trace element data, similar to major element compositions previously presented, show broadly intergradational chemistries among the several lithologies. Rare earth distributions are relatively flat at 10-30Xchondrite, with LREE relative depletions. Transition elements exhibit a marked decrease in abundance with increasing atomic number, but patterns are characterized by positive anomalies for Ti, Mn + Fe, and Ni. The bulk-rock trace element concentrations are analogous to those of oceanic tholeiites. Similar REE patterns and overlapping ranges, and sensibly identical transition element patterns, demonstrate that a continuous spectrum of compositions is present in the analyzed rocks, ...

Objectives: To evaluate the ability of 18F-labeled fluoro-2-deoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) to predict survivorship of patients with bladder cancer (BC) and/or upper urinary tract carcinoma (UUTC). Materials: Data from patients who underwent FDG PET/CT for suspicion of recurrent urothelial carcinoma (UC) between 2007 and 2015 were retrospectively collected in a multicenter study. Disease management after the introduction of FDG PET/CT in the diagnostic algorithm was assessed in all patients. Kaplan-Meier and log-rank analysis were computed for survival assessment. A Cox regression analysis was used to identify predictors of recurrence and death, for BC, UUTC, and concomitant BC and UUTC. Results: Data from 286 patients were collected. Of these, 212 had a history of BC, 38 of UUTC and 36 of concomitant BC and UUTC. Patient management was changed in 114/286 (40%) UC patients with the inclusion of FDG PET/CT, particularly in those with BC, reaching 74% (n = 90/122). After a mean follow-up period of 21 months (Interquartile range: 4&ndash, 28 mo.), 136 patients (47.4%) had recurrence/progression of disease. Moreover, 131 subjects (45.6%) died. At Kaplan-Meier analyses, patients with BC and positive PET/CT had a worse overall survival than those with a negative scan (log-rank &lt, 0.001). Furthermore, a negative PET/CT scan was associated with a lower recurrence rate than a positive examination, independently from the primary tumor site. At multivariate analysis, in patients with BC and UUTC, a positive FDG PET/CT resulted an independent predictor of disease-free and overall survival (p &lt, 0,01). Conclusions: FDG PET/CT has the potential to change patient management, particularly for patients with BC. Furthermore, it can be considered a valid survival prediction tool after primary treatment in patients with recurrent UC. However, a firm recommendation cannot be made yet. Further prospective studies are necessary to confirm our findings.

Magnetic Resonance Relaxometry (MRR) and Imaging (MRI) of water 1H nuclei, confined in high surface-to-volume ratio (S/V) systems, have been successfully applied, as non-destructive tools, to detect connected porosity and pore size distribution in different ceramic materials obtained by changing their composition or process conditions. MRI allows one to visualize the internal sections of ceramics in order to check spatial heterogeneity and MRR gives information on pore-size distribution. The Nuclear Magnetic Resonance (NMR) results are combined with those obtained by Scanning Electron Microscopy (SEM) and Mercury Intrusion Porosimetry (MIP). NMR and SEM results of low porosity ceramic samples, prepared by using different soaking times, show that the samples with longer soaking times have lower porosity and larger pores. The seeming discrepancy with MIP data can be explained by the fact that with increasing soaking times the interconnected porosity decreases and the pore size tends to increase, with reduced pore throats. For high porosity ceramic samples, SEM images show the presence of a network of plate-shaped pores with a size distribution well represented by MRR. In this case, the assumptions usually adopted to interpret MIP data in terms of pore sizes do not apply.

The possibility of recycling residues, coming from the industrial polishing process of porcelain stoneware tiles, by their incorporation in a porcelain stoneware body mix, was studied. Starting from a standard body mix, several modified body mixes were prepared by replacing different amounts of the fluxing component, a sodium feldspar sand, with these wastes. The densification behaviour of the different body mixes was investigated by determining water absorption, linear shrinkage and bulk density of the as fired specimens. Phase and microstructural examination, by quantitative X-ray diffractometry and scanning electron microscopy-energy dispersive spectroscopy, made it possible to explain the mechanical behaviour, i.e. flexural strength, Young's modulus and Weibull's modulus. The presence of polishing porcelain stoneware residues, PPR, in particular in a 10 wt% of replacement, made possible a consistent decrease in the maximum temperature of the thermal cycle. That did not cause significant variations in the mechanical strength of the materials, while a slight decrease of the elastic modulus and a remarkable increase of the reliability were registered.

The aim of the present work is to realise ceramic tiles with superior surface mechanical characteristics and chemical resistance, by the addition of nano-oxides, such as zirconia and alumina, since such advanced ceramics oxides are well known for their excellent mechanical properties and good resistance to chemical etching. In order to avoid any dangerousness, the nanoparticles were used in form of aqueous suspension and they were sprayed, by airbrush, directly onto the dried ceramic support, before firing. To observe the distribution of the nanoparticles and to optimise the surface treatment, SEM-EDS analyses were carried out on the fired samples. XRD analysis was conducted to assess the phases evolution of the different materials during the firing step. The surface mechanical characteristics of the samples have been evaluated by Vickers’ hardness and scratch test. In addition, also chemical resistance tests were performed. Microstructural observations allowed to understand how alumina and zirconia nanoparticles acted to improve the surface performances of the modified ceramic tiles.

The aim of the present work is to obtain ceramic tiles with superior surface mechanical characteristics and chemical resistance, by the addition of nano-oxides, such as zirconia and alumina, since such advanced ceramics oxides are well known for their excellent mechanical properties and good resistance to chemical attack. In order to avoid any dangerousness, the nanoparticles were used in form of aqueous suspension and they were sprayed, by airbrush, directly onto the dried ceramic support, before firing. To observe the distribution of the nanoparticles and to optimise the surface treatment, SEM-EDS analyses were carried out on the fired samples. XRD analysis was conducted to assess the phase evolution of the different materials during the firing step. The surface mechanical characteristics of the samples have been evaluated by Vickers’ hardness and scratch test. In addition, chemical resistance tests were also performed. Microstructural observations allowed how alumina and zirconia nanoparticles acted to improve the surface performances of the modified ceramic tiles to be understood.

In this work thermal conductivity of ceramic tiles is investigated in order to assess their contribution to the building energy efficiency. The aim is to correlate microstructural and physical characteristics of ceramic tiles with their thermal conductivity. A porcelain stoneware tile has been selected as reference material. The contribution of the open and closed pores to thermal conductivity is investigated by using different percentages of polymethylmethacrylate (PMMA) as pore-forming agent and by varying the firing cycle. The evaluation of the experimentally measured values evidences the strong influence of microstructure and porosity of the materials on the thermal conductivity and diffusivity.

The high temperature processing of porcelain stoneware products is attractive for the possibility to incorporate several inorganic wastes. However, even if recycling is an environmental benefit, it...

L’identificazione di nuovi siti nel territorio di Phoinike (Albania meridionale)

Ricerche, ricognizioni e saggi stratigrafici nella città alta di Phoinike (Albania meridionale)

Recycling of scrap glass in a porcelain stoneware tile body mix was studied by replacing different amounts of the fluxing component by two types of scrap glass: (i) 5, 10 and 15wt% soda-lime-silica (SLS) container glass and (ii) 2wt% Pb-based cathode ray tube glass. The densification behaviour of the standard stoneware composition and four other mixes containing recycled glass was evaluated in terms of water absorption and linear shrinkage. The microstructural evolution on firing the resulting body mixes was investigated by X-ray diffractometry (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Substituting the fluxing component with 5-10wt% SLS glass yields stoneware with reduced water absorption. The presence of 2wt% Pb-based glass in the body mix made it possible to decrease the sintering temperature by 20°C. The microstructure of the standard stoneware consists of a glassy matrix with 100-1000μm long mullite needles, feldspar relicts and partially dissolved α-quartz crystals. Using 10wt% or more SLS glass in the body mix composition led additionally to the crystallisation of a plagioclase, (Ca,Na)Al2Si2O8, which partially inhibited mullite formation. SEM analysis revealed that Ca-rich areas developed adjacent to quartz particles on firing as a result of interactions between quartz and SLS glass. Rounded wollastonite and elongated sodium silicate crystals have been also identified in SLS glass fluxed stonewares. PbO was not detected in stoneware samples containing Pb-based recycled glass, suggesting that it may evaporate on firing and/or remain as trace amounts of lead evenly distributed in the glassy phase.