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Current trends in the ceramic industry see an increasing interest on porcelain stoneware, by which is possible to produce large tiles and slabs. These products are manufactured by spray-dried powders, which have excellent technological properties but require high energy and water consumption. Dry-processed granulates allow to reduce such a consumption, but suffer from a different technological behavior. A solution to improve the environmental sustainability of ceramic tile-making is mixing powders prepared by the wet and the dry routes. The technological features of industrially manufactured mixed powders was investigated (rheological properties, compaction response and firing behavior) in order to point out advantages and possible pitfalls. Dry-processed and spray-dried granulates exhibit different distributions of size, shape and moisture that reflect on distinct rheological and compaction behaviors. Mixed powders show a more or less accentuated deviation from linearity between the end terms. This fact makes possible to add up to similar to 50% dry granulates by keeping the technological properties close to current industrial bodies. Sparings of water, energy and CO2 emission for the milling and granulation stages are estimated for a mix 50% spray-dried and 50% dry-processed powders. Las tendencias actuales en la industria cerámica ven un interés creciente en el gres porcelánico, mediante el cual es posible producir grandes baldosas y losas. Estos productos se fabrican mediante polvos atomizados, que tienen excelentes propiedades tecnológicas, pero requieren de un alto consumo de energía y agua. Los granulados procesados en seco permiten reducir dicho consumo, pero presentan un comportamiento tecnológico diferente. Una solución para mejorar la sostenibilidad medioambiental de la fabricación de baldosas cerámicas es mezclar polvos preparados por vía húmeda y seca. Se investigaron las características tecnológicas de los polvos mixtos fabricados industrialmente (propiedades reológicas, respuesta de compactación y comportamiento en cocción), con el fin de senalar ˜ las ventajas y posibles inconvenientes. Los granulados procesados en seco y atomizados exhiben diferentes distribuciones de tamano, ˜ forma y humedad que se reflejan en distintos comportamientos reológicos y de compactación. Los polvos mixtos muestran una desviación más o menos acentuada de la linealidad entre los extremos. Este hecho permite anadir ˜ hasta ∼50% de granulado seco manteniendo las propiedades tecnológicas próximas a las piezas industriales actuales. Los ahorros de agua, energía y de emisiones de CO2 para las etapas de molienda y granulación se estiman para una mezcla de 50% de polvo atomizado y 50% de polvo granulado vía seca.

Partendo dall’esame di alcuni contributi di Francesco Parrillo, compresi in un arco temporale che va dal 1983 al 1999, sul tema delle PMI (anche nei suoi riflessi finanziari), l’articolo propone una attualizzazione di quella riflessione per interpretare la realtà del sistema produttivo italiano nella seconda decade del nuovo millennio. I temi emergenti sono legati alla vitalità delle medie imprese, alla nuova manifattura digitale, ad una maggiore attenzione per la diversificazione delle fonti di finanziamento. A fronte di questi spiragli, permangono alcuni nodi critici strutturali come le difficoltà della maggior parte delle imprese, segnate dalla ridotta dimensione, la loro sottocapitalizzazione, i modelli superati di governance, che, a livello macroeconomico, comportano bassi livelli di produttività. Al riguardo viene condotta un’analisi econometrica per testare l’ipotesi che una “soluzione” possa venire da reti d’impresa che collaborano su progetti mirati di innovazione (e/o internazionalizzazione). Starting from an accurate selection of contributions written, in the 1983-1999 period, by Francesco Parrillo on SMEs (also in its financial implications), the paper proposes to contextualize its analysis in recent times, in order to interpret the modern nature of the Italian productive system. Emerging relevant topics arerelated to the dynamism of Medium-sized firms, the new digital manufacture, and to the diversification of funding sources. However, critical issues still remain, such as small dimension, undercapitalization, outdated governance, which imply low productivity levels. In this regard, we propose an econometric analysis to test the hypothesis that a “solution” can come from business networks with firms that collaborate on targeted innovation (and/or internationalization) projects.

Waste recycling has become an important issue in the environmental sustainability of mining operations. Beneficiation of borate ores produces a boron-bearing sludge, which utilization in ceramic manufacturing may lower the process energy demand. A case-study was carried out on a sludge coming from the processed ore of an evaporite located at the Tincalayu mine in the Salta province, Argentina. The use in vitrified tiles of this sludge was appraised addressing key-points in processing and product performances. The sludge was added to stoneware batches (up to 10% wt.) and tested at the laboratory scale. It consists of feldspars, quartz, illite and chlorite, plus ulexite (6.4% B2O3) that turns this sludge into a powerful flux. The waste had a minor effect during milling but allowed an improved compaction. The reactivity during firing was increased: the maximum temperature can be reduced from 1200 degrees C down to 1140 degrees C, according to the amount of sludge added. Stoneware tiles have a suitable technical performance, but the sludge tends to lower bulk density and increase closed porosity. Although the influence on phase composition is apparently limited, the sludge can significantly change the melt composition (enriched in boron and alkaline-earth oxides) which governs the sintering behavior. The actual amount of boron sludge recyclable in vitrified tiles is up to 5% by weight. El reciclaje de desechos se ha convertido en un tema importante en la sostenibilidad ambiental de las operaciones mineras. El beneficio de los minerales de borato produce un lodo que contiene boro, cuya utilización en la fabricación de cerámica puede reducir la demanda de energía del proceso. El lodo estudiado proviene del mineral procesado de una evaporita ubicada en la mina Tincalayu en la provincia de Salta, Argentina. El uso en azulejos vitrificados de ese lodo se evaluó abordando los puntos clave en el procesamiento y el rendimiento del producto. El lodo se agregó a los lotes de gres (hasta el 10% en peso) y se probó a escala de laboratorio. Se compone de feldespatos, cuarzo, illita y clorita, más ulexita (6,4% B2O3) que convierte este lodo en un poderoso fundente. El desecho tuvo un efecto menor durante la molienda, pero permitió una compactación mejorada. La reactividad durante la cocción aumentó: la temperatura máxima se puede reducir de 1200 ◦C a 1140 ◦C, según la cantidad de lodo anadida. ˜ Las baldosas de gres tienen un rendimiento técnico adecuado, pero el lodo tiende a reducir la densidad aparente y aumentar la porosidad cerrada. Aunque la influencia en la composición de la fase es aparentemente limitada, el lodo puede cambiar significativamente la composición de la masa fundida (enriquecida en óxidos de boro y alcalino-térreos) que rige el comportamiento de sinterización. La cantidad real de lodo reciclable en baldosas vitrificadas es hasta el 5% en peso.

In the building sector, over recent years it is ever more important the development of new solutions to improve energy efficiency and savings, particularly due to the demanding EU directive. The implementation of ventilated façades, on new and existing buildings, offers the possibility to reduce costs and promote the acoustic and thermal insulation. The thermal behavior of the external layer influences the building performances: for this purpose a ceramic foam based device was studies. The ceramic formulation was defined in order to be easily integrated within the existing tilesproduction process. Furthermore, a waste glass was added in order to evaluate recyclability and feasibility for ceramic foams. Given by the key role played by the porosity into the thermal conductibility definition, the effect of composition and process parameters on the ceramic properties were studied and optimized. The obtained materials were also thermally characterized. In order to achieve an higher thermal inertia, the possibility to incorporate a Phase Change Material into the ceramic body was investigated. The effect of different methodology of PCM-integration were compared, in order to pointing out the role of its dispersion into the definition of thermal behavior. A lab- size scale-up process was also performed until the demo obtaining.

The firing behavior of porcelain stoneware slabs depends not only on kiln conditions (time, temperature) but also on the rheological characteristics and the response to compaction of spray-dried powders. Although in the literature there are information on the characteristics of spray-dried powders for ceramic tiles, no data are available on bodies for manufacturing large slabs (>4 m2) with new technologies. A systematic approach to the properties and behavior of nine industrial spray-dried powders for porcelain stoneware slabs was set out by the IPERCER project. In addition to the rheological properties of powders and their compaction behavior, it has been carefully observed the firing behavior (effect of the porosity and density of the green on the firing shrinkage, bulk density, open and closed porosity, phase composition), trying to correlate among them all the data collected. Main goal is to obtain a data-based model of the sintering behavior and to optimize the characteristics of fired slabs in terms of homogeneity (shrinkage), bulk density, water absorption, porosity and mechanical strength. Concluding, with an overall analysis of the entire ceramic production process, we infer the chance of improving the performance of spray dried bodies by finding a compromise between powder flowabity, compaction and densification during firing. Final challenge is to transfer this progress to the management of industrial spray driers.

The interpretation of the heart as a mechanical engine dates back to the teachings of Leonardo da Vinci, who was the first to apply the laws of mechanics to the function of the heart. Similar to any mechanical engine, whose performance is proportional to the power generated with respect to weight, the left ventricle can be viewed as a power generator whose performance can be related to left ventricular mass. Stress echocardiography may provide valuable information on the relationship between cardiac performance and recruited left ventricular mass that may be used in distinguishing between adaptive and maladaptive left ventricular remodeling. Peak power output-to-mass, obtained during exercise or pharmacological stress echocardiography, is a measure that reflects the number of watts that are developed by 100 g of left ventricular mass under maximal stimulation. Power output-to-mass may be calculated as left ventricular power output per 100 g of left ventricular mass: 100× left ventricular power output divided by left ventricular mass (W/100 g). A simplified formula to calculate power output-to-mass is as follows: 0.222 × cardiac output (l/min) × mean blood pressure (mmHg)/left ventricular mass (g). When the integrity of myocardial structure is compromised, a mismatch becomes apparent between maximal cardiac power output and left ventricular mass; when this occurs, a reduction of the peak power output-to-mass index is observed.

Low-cost, naturally-occurring mixtures of feldspar and zeolite occurring in epiclastic rocks are promising substitutes for conventional quartz-feldspathic fluxes in ceramic bodies, since their fusibility and low hardness are expected to improve both grinding and sintering. Three epiclastic outcrops, with a different zeolite-to-feldspar ratio, were characterized (XRPD, fusibility) and tested in porcelain stoneware bodies; their behaviour during processing was appraised and compared with that of a reference. The addition of an epiclastic rock (20 wt.%), replacing rhyolite and aplite fluxes, brought about some significant advantages, mainly represented by better grindability, lower firing temperature with improved mechanical strength and lower porosity. Disadvantages concern increased slip viscosity, worse powder compressibility, resulting in larger firing shrinkage, and a darker colour of the tiles due to relatively high amounts of iron oxide.

Low-cost zeolitic rocks are promising substitutes for feldspathic fluxes in ceramic bodies, since their fusibility, scarce hardness and high CEC should improve grinding and sintering. Five large-scale Italian deposits with different mineralogy were characterised and used in porcelain stoneware bodies. Their behaviour during grinding, pressing, drying and firing was appraised in laboratory and compared with zeolite-free bodies. Zeolites increased the slip viscosity during wet grinding, causing a coarser grain size distribution and consequently some drawbacks in both unfired and fired tiles. Overcoming this hindrance by dry grinding of zeolitites, the technological behaviour of zeolite-bearing tiles appear to be similar to current porcelain stoneware, though with larger firing shrinkage and residual closed porosity.